* [PATCH v3 5/6] to be squashed into 3/6 (chunk 2 of 3)
From: Johannes Schindelin via GitGitGadget @ 2026-05-08 12:51 UTC (permalink / raw)
To: git; +Cc: Patrick Steinhardt, Johannes Schindelin, Johannes Schindelin
In-Reply-To: <pull.2104.v3.git.1778244661.gitgitgadget@gmail.com>
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Assisted-by: Opus 4.7
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
compat/nedmalloc/malloc.c.h | 1699 -----------------------------------
1 file changed, 1699 deletions(-)
diff --git a/compat/nedmalloc/malloc.c.h b/compat/nedmalloc/malloc.c.h
index b4fb8c8846..0c663cf49c 100644
--- a/compat/nedmalloc/malloc.c.h
+++ b/compat/nedmalloc/malloc.c.h
@@ -1,1702 +1,3 @@
-/* ---------------------- Overlaid data structures ----------------------- */
-
-/*
- When chunks are not in use, they are treated as nodes of either
- lists or trees.
-
- "Small" chunks are stored in circular doubly-linked lists, and look
- like this:
-
- chunk-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- | Size of previous chunk |
- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- `head:' | Size of chunk, in bytes |P|
- mem-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- | Forward pointer to next chunk in list |
- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- | Back pointer to previous chunk in list |
- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- | Unused space (may be 0 bytes long) .
- . .
- . |
-nextchunk-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- `foot:' | Size of chunk, in bytes |
- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
-
- Larger chunks are kept in a form of bitwise digital trees (aka
- tries) keyed on chunksizes. Because malloc_tree_chunks are only for
- free chunks greater than 256 bytes, their size doesn't impose any
- constraints on user chunk sizes. Each node looks like:
-
- chunk-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- | Size of previous chunk |
- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- `head:' | Size of chunk, in bytes |P|
- mem-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- | Forward pointer to next chunk of same size |
- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- | Back pointer to previous chunk of same size |
- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- | Pointer to left child (child[0]) |
- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- | Pointer to right child (child[1]) |
- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- | Pointer to parent |
- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- | bin index of this chunk |
- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- | Unused space .
- . |
-nextchunk-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- `foot:' | Size of chunk, in bytes |
- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
-
- Each tree holding treenodes is a tree of unique chunk sizes. Chunks
- of the same size are arranged in a circularly-linked list, with only
- the oldest chunk (the next to be used, in our FIFO ordering)
- actually in the tree. (Tree members are distinguished by a non-null
- parent pointer.) If a chunk with the same size as an existing node
- is inserted, it is linked off the existing node using pointers that
- work in the same way as fd/bk pointers of small chunks.
-
- Each tree contains a power of 2 sized range of chunk sizes (the
- smallest is 0x100 <= x < 0x180), which is divided in half at each
- tree level, with the chunks in the smaller half of the range (0x100
- <= x < 0x140 for the top nose) in the left subtree and the larger
- half (0x140 <= x < 0x180) in the right subtree. This is, of course,
- done by inspecting individual bits.
-
- Using these rules, each node's left subtree contains all smaller
- sizes than its right subtree. However, the node at the root of each
- subtree has no particular ordering relationship to either. (The
- dividing line between the subtree sizes is based on trie relation.)
- If we remove the last chunk of a given size from the interior of the
- tree, we need to replace it with a leaf node. The tree ordering
- rules permit a node to be replaced by any leaf below it.
-
- The smallest chunk in a tree (a common operation in a best-fit
- allocator) can be found by walking a path to the leftmost leaf in
- the tree. Unlike a usual binary tree, where we follow left child
- pointers until we reach a null, here we follow the right child
- pointer any time the left one is null, until we reach a leaf with
- both child pointers null. The smallest chunk in the tree will be
- somewhere along that path.
-
- The worst case number of steps to add, find, or remove a node is
- bounded by the number of bits differentiating chunks within
- bins. Under current bin calculations, this ranges from 6 up to 21
- (for 32 bit sizes) or up to 53 (for 64 bit sizes). The typical case
- is of course much better.
-*/
-
-struct malloc_tree_chunk {
- /* The first four fields must be compatible with malloc_chunk */
- size_t prev_foot;
- size_t head;
- struct malloc_tree_chunk* fd;
- struct malloc_tree_chunk* bk;
-
- struct malloc_tree_chunk* child[2];
- struct malloc_tree_chunk* parent;
- bindex_t index;
-};
-
-typedef struct malloc_tree_chunk tchunk;
-typedef struct malloc_tree_chunk* tchunkptr;
-typedef struct malloc_tree_chunk* tbinptr; /* The type of bins of trees */
-
-/* A little helper macro for trees */
-#define leftmost_child(t) ((t)->child[0] != 0? (t)->child[0] : (t)->child[1])
-
-/* ----------------------------- Segments -------------------------------- */
-
-/*
- Each malloc space may include non-contiguous segments, held in a
- list headed by an embedded malloc_segment record representing the
- top-most space. Segments also include flags holding properties of
- the space. Large chunks that are directly allocated by mmap are not
- included in this list. They are instead independently created and
- destroyed without otherwise keeping track of them.
-
- Segment management mainly comes into play for spaces allocated by
- MMAP. Any call to MMAP might or might not return memory that is
- adjacent to an existing segment. MORECORE normally contiguously
- extends the current space, so this space is almost always adjacent,
- which is simpler and faster to deal with. (This is why MORECORE is
- used preferentially to MMAP when both are available -- see
- sys_alloc.) When allocating using MMAP, we don't use any of the
- hinting mechanisms (inconsistently) supported in various
- implementations of unix mmap, or distinguish reserving from
- committing memory. Instead, we just ask for space, and exploit
- contiguity when we get it. It is probably possible to do
- better than this on some systems, but no general scheme seems
- to be significantly better.
-
- Management entails a simpler variant of the consolidation scheme
- used for chunks to reduce fragmentation -- new adjacent memory is
- normally prepended or appended to an existing segment. However,
- there are limitations compared to chunk consolidation that mostly
- reflect the fact that segment processing is relatively infrequent
- (occurring only when getting memory from system) and that we
- don't expect to have huge numbers of segments:
-
- * Segments are not indexed, so traversal requires linear scans. (It
- would be possible to index these, but is not worth the extra
- overhead and complexity for most programs on most platforms.)
- * New segments are only appended to old ones when holding top-most
- memory; if they cannot be prepended to others, they are held in
- different segments.
-
- Except for the top-most segment of an mstate, each segment record
- is kept at the tail of its segment. Segments are added by pushing
- segment records onto the list headed by &mstate.seg for the
- containing mstate.
-
- Segment flags control allocation/merge/deallocation policies:
- * If EXTERN_BIT set, then we did not allocate this segment,
- and so should not try to deallocate or merge with others.
- (This currently holds only for the initial segment passed
- into create_mspace_with_base.)
- * If IS_MMAPPED_BIT set, the segment may be merged with
- other surrounding mmapped segments and trimmed/de-allocated
- using munmap.
- * If neither bit is set, then the segment was obtained using
- MORECORE so can be merged with surrounding MORECORE'd segments
- and deallocated/trimmed using MORECORE with negative arguments.
-*/
-
-struct malloc_segment {
- char* base; /* base address */
- size_t size; /* allocated size */
- struct malloc_segment* next; /* ptr to next segment */
- flag_t sflags; /* mmap and extern flag */
-};
-
-#define is_mmapped_segment(S) ((S)->sflags & IS_MMAPPED_BIT)
-#define is_extern_segment(S) ((S)->sflags & EXTERN_BIT)
-
-typedef struct malloc_segment msegment;
-typedef struct malloc_segment* msegmentptr;
-
-/* ---------------------------- malloc_state ----------------------------- */
-
-/*
- A malloc_state holds all of the bookkeeping for a space.
- The main fields are:
-
- Top
- The topmost chunk of the currently active segment. Its size is
- cached in topsize. The actual size of topmost space is
- topsize+TOP_FOOT_SIZE, which includes space reserved for adding
- fenceposts and segment records if necessary when getting more
- space from the system. The size at which to autotrim top is
- cached from mparams in trim_check, except that it is disabled if
- an autotrim fails.
-
- Designated victim (dv)
- This is the preferred chunk for servicing small requests that
- don't have exact fits. It is normally the chunk split off most
- recently to service another small request. Its size is cached in
- dvsize. The link fields of this chunk are not maintained since it
- is not kept in a bin.
-
- SmallBins
- An array of bin headers for free chunks. These bins hold chunks
- with sizes less than MIN_LARGE_SIZE bytes. Each bin contains
- chunks of all the same size, spaced 8 bytes apart. To simplify
- use in double-linked lists, each bin header acts as a malloc_chunk
- pointing to the real first node, if it exists (else pointing to
- itself). This avoids special-casing for headers. But to avoid
- waste, we allocate only the fd/bk pointers of bins, and then use
- repositioning tricks to treat these as the fields of a chunk.
-
- TreeBins
- Treebins are pointers to the roots of trees holding a range of
- sizes. There are 2 equally spaced treebins for each power of two
- from TREE_SHIFT to TREE_SHIFT+16. The last bin holds anything
- larger.
-
- Bin maps
- There is one bit map for small bins ("smallmap") and one for
- treebins ("treemap). Each bin sets its bit when non-empty, and
- clears the bit when empty. Bit operations are then used to avoid
- bin-by-bin searching -- nearly all "search" is done without ever
- looking at bins that won't be selected. The bit maps
- conservatively use 32 bits per map word, even if on 64bit system.
- For a good description of some of the bit-based techniques used
- here, see Henry S. Warren Jr's book "Hacker's Delight" (and
- supplement at http://hackersdelight.org/). Many of these are
- intended to reduce the branchiness of paths through malloc etc, as
- well as to reduce the number of memory locations read or written.
-
- Segments
- A list of segments headed by an embedded malloc_segment record
- representing the initial space.
-
- Address check support
- The least_addr field is the least address ever obtained from
- MORECORE or MMAP. Attempted frees and reallocs of any address less
- than this are trapped (unless INSECURE is defined).
-
- Magic tag
- A cross-check field that should always hold same value as mparams.magic.
-
- Flags
- Bits recording whether to use MMAP, locks, or contiguous MORECORE
-
- Statistics
- Each space keeps track of current and maximum system memory
- obtained via MORECORE or MMAP.
-
- Trim support
- Fields holding the amount of unused topmost memory that should trigger
- timing, and a counter to force periodic scanning to release unused
- non-topmost segments.
-
- Locking
- If USE_LOCKS is defined, the "mutex" lock is acquired and released
- around every public call using this mspace.
-
- Extension support
- A void* pointer and a size_t field that can be used to help implement
- extensions to this malloc.
-*/
-
-/* Bin types, widths and sizes */
-#define NSMALLBINS (32U)
-#define NTREEBINS (32U)
-#define SMALLBIN_SHIFT (3U)
-#define SMALLBIN_WIDTH (SIZE_T_ONE << SMALLBIN_SHIFT)
-#define TREEBIN_SHIFT (8U)
-#define MIN_LARGE_SIZE (SIZE_T_ONE << TREEBIN_SHIFT)
-#define MAX_SMALL_SIZE (MIN_LARGE_SIZE - SIZE_T_ONE)
-#define MAX_SMALL_REQUEST (MAX_SMALL_SIZE - CHUNK_ALIGN_MASK - CHUNK_OVERHEAD)
-
-struct malloc_state {
- binmap_t smallmap;
- binmap_t treemap;
- size_t dvsize;
- size_t topsize;
- char* least_addr;
- mchunkptr dv;
- mchunkptr top;
- size_t trim_check;
- size_t release_checks;
- size_t magic;
- mchunkptr smallbins[(NSMALLBINS+1)*2];
- tbinptr treebins[NTREEBINS];
- size_t footprint;
- size_t max_footprint;
- flag_t mflags;
-#if USE_LOCKS
- MLOCK_T mutex; /* locate lock among fields that rarely change */
-#endif /* USE_LOCKS */
- msegment seg;
- void* extp; /* Unused but available for extensions */
- size_t exts;
-};
-
-typedef struct malloc_state* mstate;
-
-/* ------------- Global malloc_state and malloc_params ------------------- */
-
-/*
- malloc_params holds global properties, including those that can be
- dynamically set using mallopt. There is a single instance, mparams,
- initialized in init_mparams. Note that the non-zeroness of "magic"
- also serves as an initialization flag.
-*/
-
-struct malloc_params {
- volatile size_t magic;
- size_t page_size;
- size_t granularity;
- size_t mmap_threshold;
- size_t trim_threshold;
- flag_t default_mflags;
-};
-
-static struct malloc_params mparams;
-
-/* Ensure mparams initialized */
-#define ensure_initialization() ((void)(mparams.magic != 0 || init_mparams()))
-
-#if !ONLY_MSPACES
-
-/* The global malloc_state used for all non-"mspace" calls */
-static struct malloc_state _gm_;
-#define gm (&_gm_)
-#define is_global(M) ((M) == &_gm_)
-
-#endif /* !ONLY_MSPACES */
-
-#define is_initialized(M) ((M)->top != 0)
-
-/* -------------------------- system alloc setup ------------------------- */
-
-/* Operations on mflags */
-
-#define use_lock(M) ((M)->mflags & USE_LOCK_BIT)
-#define enable_lock(M) ((M)->mflags |= USE_LOCK_BIT)
-#define disable_lock(M) ((M)->mflags &= ~USE_LOCK_BIT)
-
-#define use_mmap(M) ((M)->mflags & USE_MMAP_BIT)
-#define enable_mmap(M) ((M)->mflags |= USE_MMAP_BIT)
-#define disable_mmap(M) ((M)->mflags &= ~USE_MMAP_BIT)
-
-#define use_noncontiguous(M) ((M)->mflags & USE_NONCONTIGUOUS_BIT)
-#define disable_contiguous(M) ((M)->mflags |= USE_NONCONTIGUOUS_BIT)
-
-#define set_lock(M,L)\
- ((M)->mflags = (L)?\
- ((M)->mflags | USE_LOCK_BIT) :\
- ((M)->mflags & ~USE_LOCK_BIT))
-
-/* page-align a size */
-#define page_align(S)\
- (((S) + (mparams.page_size - SIZE_T_ONE)) & ~(mparams.page_size - SIZE_T_ONE))
-
-/* granularity-align a size */
-#define granularity_align(S)\
- (((S) + (mparams.granularity - SIZE_T_ONE))\
- & ~(mparams.granularity - SIZE_T_ONE))
-
-
-/* For mmap, use granularity alignment on windows, else page-align */
-#ifdef WIN32
-#define mmap_align(S) granularity_align(S)
-#else
-#define mmap_align(S) page_align(S)
-#endif
-
-/* For sys_alloc, enough padding to ensure can malloc request on success */
-#define SYS_ALLOC_PADDING (TOP_FOOT_SIZE + MALLOC_ALIGNMENT)
-
-#define is_page_aligned(S)\
- (((size_t)(S) & (mparams.page_size - SIZE_T_ONE)) == 0)
-#define is_granularity_aligned(S)\
- (((size_t)(S) & (mparams.granularity - SIZE_T_ONE)) == 0)
-
-/* True if segment S holds address A */
-#define segment_holds(S, A)\
- ((char*)(A) >= S->base && (char*)(A) < S->base + S->size)
-
-/* Return segment holding given address */
-static msegmentptr segment_holding(mstate m, char* addr) {
- msegmentptr sp = &m->seg;
- for (;;) {
- if (addr >= sp->base && addr < sp->base + sp->size)
- return sp;
- if ((sp = sp->next) == 0)
- return 0;
- }
-}
-
-/* Return true if segment contains a segment link */
-static int has_segment_link(mstate m, msegmentptr ss) {
- msegmentptr sp = &m->seg;
- for (;;) {
- if ((char*)sp >= ss->base && (char*)sp < ss->base + ss->size)
- return 1;
- if ((sp = sp->next) == 0)
- return 0;
- }
-}
-
-#ifndef MORECORE_CANNOT_TRIM
-#define should_trim(M,s) ((s) > (M)->trim_check)
-#else /* MORECORE_CANNOT_TRIM */
-#define should_trim(M,s) (0)
-#endif /* MORECORE_CANNOT_TRIM */
-
-/*
- TOP_FOOT_SIZE is padding at the end of a segment, including space
- that may be needed to place segment records and fenceposts when new
- noncontiguous segments are added.
-*/
-#define TOP_FOOT_SIZE\
- (align_offset(chunk2mem(0))+pad_request(sizeof(struct malloc_segment))+MIN_CHUNK_SIZE)
-
-
-/* ------------------------------- Hooks -------------------------------- */
-
-/*
- PREACTION should be defined to return 0 on success, and nonzero on
- failure. If you are not using locking, you can redefine these to do
- anything you like.
-*/
-
-#if USE_LOCKS
-
-#define PREACTION(M) ((use_lock(M))? ACQUIRE_LOCK(&(M)->mutex) : 0)
-#define POSTACTION(M) { if (use_lock(M)) RELEASE_LOCK(&(M)->mutex); }
-#else /* USE_LOCKS */
-
-#ifndef PREACTION
-#define PREACTION(M) (0)
-#endif /* PREACTION */
-
-#ifndef POSTACTION
-#define POSTACTION(M)
-#endif /* POSTACTION */
-
-#endif /* USE_LOCKS */
-
-/*
- CORRUPTION_ERROR_ACTION is triggered upon detected bad addresses.
- USAGE_ERROR_ACTION is triggered on detected bad frees and
- reallocs. The argument p is an address that might have triggered the
- fault. It is ignored by the two predefined actions, but might be
- useful in custom actions that try to help diagnose errors.
-*/
-
-#if PROCEED_ON_ERROR
-
-/* A count of the number of corruption errors causing resets */
-int malloc_corruption_error_count;
-
-/* default corruption action */
-static void reset_on_error(mstate m);
-
-#define CORRUPTION_ERROR_ACTION(m) reset_on_error(m)
-#define USAGE_ERROR_ACTION(m, p)
-
-#else /* PROCEED_ON_ERROR */
-
-#ifndef CORRUPTION_ERROR_ACTION
-#define CORRUPTION_ERROR_ACTION(m) ABORT
-#endif /* CORRUPTION_ERROR_ACTION */
-
-#ifndef USAGE_ERROR_ACTION
-#define USAGE_ERROR_ACTION(m,p) ABORT
-#endif /* USAGE_ERROR_ACTION */
-
-#endif /* PROCEED_ON_ERROR */
-
-/* -------------------------- Debugging setup ---------------------------- */
-
-#if ! DEBUG
-
-#define check_free_chunk(M,P)
-#define check_inuse_chunk(M,P)
-#define check_malloced_chunk(M,P,N)
-#define check_mmapped_chunk(M,P)
-#define check_malloc_state(M)
-#define check_top_chunk(M,P)
-
-#else /* DEBUG */
-#define check_free_chunk(M,P) do_check_free_chunk(M,P)
-#define check_inuse_chunk(M,P) do_check_inuse_chunk(M,P)
-#define check_top_chunk(M,P) do_check_top_chunk(M,P)
-#define check_malloced_chunk(M,P,N) do_check_malloced_chunk(M,P,N)
-#define check_mmapped_chunk(M,P) do_check_mmapped_chunk(M,P)
-#define check_malloc_state(M) do_check_malloc_state(M)
-
-static void do_check_any_chunk(mstate m, mchunkptr p);
-static void do_check_top_chunk(mstate m, mchunkptr p);
-static void do_check_mmapped_chunk(mstate m, mchunkptr p);
-static void do_check_inuse_chunk(mstate m, mchunkptr p);
-static void do_check_free_chunk(mstate m, mchunkptr p);
-static void do_check_malloced_chunk(mstate m, void* mem, size_t s);
-static void do_check_tree(mstate m, tchunkptr t);
-static void do_check_treebin(mstate m, bindex_t i);
-static void do_check_smallbin(mstate m, bindex_t i);
-static void do_check_malloc_state(mstate m);
-static int bin_find(mstate m, mchunkptr x);
-static size_t traverse_and_check(mstate m);
-#endif /* DEBUG */
-
-/* ---------------------------- Indexing Bins ---------------------------- */
-
-#define is_small(s) (((s) >> SMALLBIN_SHIFT) < NSMALLBINS)
-#define small_index(s) ((s) >> SMALLBIN_SHIFT)
-#define small_index2size(i) ((i) << SMALLBIN_SHIFT)
-#define MIN_SMALL_INDEX (small_index(MIN_CHUNK_SIZE))
-
-/* addressing by index. See above about smallbin repositioning */
-#define smallbin_at(M, i) ((sbinptr)((char*)&((M)->smallbins[(i)<<1])))
-#define treebin_at(M,i) (&((M)->treebins[i]))
-
-/* assign tree index for size S to variable I. Use x86 asm if possible */
-#if defined(__GNUC__) && (defined(__i386__) || defined(__x86_64__))
-#define compute_tree_index(S, I)\
-{\
- unsigned int X = S >> TREEBIN_SHIFT;\
- if (X == 0)\
- I = 0;\
- else if (X > 0xFFFF)\
- I = NTREEBINS-1;\
- else {\
- unsigned int K;\
- __asm__("bsrl\t%1, %0\n\t" : "=r" (K) : "rm" (X));\
- I = (bindex_t)((K << 1) + ((S >> (K + (TREEBIN_SHIFT-1)) & 1)));\
- }\
-}
-
-#elif defined (__INTEL_COMPILER)
-#define compute_tree_index(S, I)\
-{\
- size_t X = S >> TREEBIN_SHIFT;\
- if (X == 0)\
- I = 0;\
- else if (X > 0xFFFF)\
- I = NTREEBINS-1;\
- else {\
- unsigned int K = _bit_scan_reverse (X); \
- I = (bindex_t)((K << 1) + ((S >> (K + (TREEBIN_SHIFT-1)) & 1)));\
- }\
-}
-
-#elif defined(_MSC_VER) && _MSC_VER>=1300
-#define compute_tree_index(S, I)\
-{\
- size_t X = S >> TREEBIN_SHIFT;\
- if (X == 0)\
- I = 0;\
- else if (X > 0xFFFF)\
- I = NTREEBINS-1;\
- else {\
- unsigned int K;\
- _BitScanReverse((DWORD *) &K, X);\
- I = (bindex_t)((K << 1) + ((S >> (K + (TREEBIN_SHIFT-1)) & 1)));\
- }\
-}
-
-#else /* GNUC */
-#define compute_tree_index(S, I)\
-{\
- size_t X = S >> TREEBIN_SHIFT;\
- if (X == 0)\
- I = 0;\
- else if (X > 0xFFFF)\
- I = NTREEBINS-1;\
- else {\
- unsigned int Y = (unsigned int)X;\
- unsigned int N = ((Y - 0x100) >> 16) & 8;\
- unsigned int K = (((Y <<= N) - 0x1000) >> 16) & 4;\
- N += K;\
- N += K = (((Y <<= K) - 0x4000) >> 16) & 2;\
- K = 14 - N + ((Y <<= K) >> 15);\
- I = (K << 1) + ((S >> (K + (TREEBIN_SHIFT-1)) & 1));\
- }\
-}
-#endif /* GNUC */
-
-/* Bit representing maximum resolved size in a treebin at i */
-#define bit_for_tree_index(i) \
- (i == NTREEBINS-1)? (SIZE_T_BITSIZE-1) : (((i) >> 1) + TREEBIN_SHIFT - 2)
-
-/* Shift placing maximum resolved bit in a treebin at i as sign bit */
-#define leftshift_for_tree_index(i) \
- ((i == NTREEBINS-1)? 0 : \
- ((SIZE_T_BITSIZE-SIZE_T_ONE) - (((i) >> 1) + TREEBIN_SHIFT - 2)))
-
-/* The size of the smallest chunk held in bin with index i */
-#define minsize_for_tree_index(i) \
- ((SIZE_T_ONE << (((i) >> 1) + TREEBIN_SHIFT)) | \
- (((size_t)((i) & SIZE_T_ONE)) << (((i) >> 1) + TREEBIN_SHIFT - 1)))
-
-
-/* ------------------------ Operations on bin maps ----------------------- */
-
-/* bit corresponding to given index */
-#define idx2bit(i) ((binmap_t)(1) << (i))
-
-/* Mark/Clear bits with given index */
-#define mark_smallmap(M,i) ((M)->smallmap |= idx2bit(i))
-#define clear_smallmap(M,i) ((M)->smallmap &= ~idx2bit(i))
-#define smallmap_is_marked(M,i) ((M)->smallmap & idx2bit(i))
-
-#define mark_treemap(M,i) ((M)->treemap |= idx2bit(i))
-#define clear_treemap(M,i) ((M)->treemap &= ~idx2bit(i))
-#define treemap_is_marked(M,i) ((M)->treemap & idx2bit(i))
-
-/* isolate the least set bit of a bitmap */
-#define least_bit(x) ((x) & -(x))
-
-/* mask with all bits to left of least bit of x on */
-#define left_bits(x) ((x<<1) | -(x<<1))
-
-/* mask with all bits to left of or equal to least bit of x on */
-#define same_or_left_bits(x) ((x) | -(x))
-
-/* index corresponding to given bit. Use x86 asm if possible */
-
-#if defined(__GNUC__) && (defined(__i386__) || defined(__x86_64__))
-#define compute_bit2idx(X, I)\
-{\
- unsigned int J;\
- __asm__("bsfl\t%1, %0\n\t" : "=r" (J) : "rm" (X));\
- I = (bindex_t)J;\
-}
-
-#elif defined (__INTEL_COMPILER)
-#define compute_bit2idx(X, I)\
-{\
- unsigned int J;\
- J = _bit_scan_forward (X); \
- I = (bindex_t)J;\
-}
-
-#elif defined(_MSC_VER) && _MSC_VER>=1300
-#define compute_bit2idx(X, I)\
-{\
- unsigned int J;\
- _BitScanForward((DWORD *) &J, X);\
- I = (bindex_t)J;\
-}
-
-#elif USE_BUILTIN_FFS
-#define compute_bit2idx(X, I) I = ffs(X)-1
-
-#else
-#define compute_bit2idx(X, I)\
-{\
- unsigned int Y = X - 1;\
- unsigned int K = Y >> (16-4) & 16;\
- unsigned int N = K; Y >>= K;\
- N += K = Y >> (8-3) & 8; Y >>= K;\
- N += K = Y >> (4-2) & 4; Y >>= K;\
- N += K = Y >> (2-1) & 2; Y >>= K;\
- N += K = Y >> (1-0) & 1; Y >>= K;\
- I = (bindex_t)(N + Y);\
-}
-#endif /* GNUC */
-
-
-/* ----------------------- Runtime Check Support ------------------------- */
-
-/*
- For security, the main invariant is that malloc/free/etc never
- writes to a static address other than malloc_state, unless static
- malloc_state itself has been corrupted, which cannot occur via
- malloc (because of these checks). In essence this means that we
- believe all pointers, sizes, maps etc held in malloc_state, but
- check all of those linked or offsetted from other embedded data
- structures. These checks are interspersed with main code in a way
- that tends to minimize their run-time cost.
-
- When FOOTERS is defined, in addition to range checking, we also
- verify footer fields of inuse chunks, which can be used guarantee
- that the mstate controlling malloc/free is intact. This is a
- streamlined version of the approach described by William Robertson
- et al in "Run-time Detection of Heap-based Overflows" LISA'03
- http://www.usenix.org/events/lisa03/tech/robertson.html The footer
- of an inuse chunk holds the xor of its mstate and a random seed,
- that is checked upon calls to free() and realloc(). This is
- (probablistically) unguessable from outside the program, but can be
- computed by any code successfully malloc'ing any chunk, so does not
- itself provide protection against code that has already broken
- security through some other means. Unlike Robertson et al, we
- always dynamically check addresses of all offset chunks (previous,
- next, etc). This turns out to be cheaper than relying on hashes.
-*/
-
-#if !INSECURE
-/* Check if address a is at least as high as any from MORECORE or MMAP */
-#define ok_address(M, a) ((char*)(a) >= (M)->least_addr)
-/* Check if address of next chunk n is higher than base chunk p */
-#define ok_next(p, n) ((char*)(p) < (char*)(n))
-/* Check if p has its cinuse bit on */
-#define ok_cinuse(p) cinuse(p)
-/* Check if p has its pinuse bit on */
-#define ok_pinuse(p) pinuse(p)
-
-#else /* !INSECURE */
-#define ok_address(M, a) (1)
-#define ok_next(b, n) (1)
-#define ok_cinuse(p) (1)
-#define ok_pinuse(p) (1)
-#endif /* !INSECURE */
-
-#if (FOOTERS && !INSECURE)
-/* Check if (alleged) mstate m has expected magic field */
-#define ok_magic(M) ((M)->magic == mparams.magic)
-#else /* (FOOTERS && !INSECURE) */
-#define ok_magic(M) (1)
-#endif /* (FOOTERS && !INSECURE) */
-
-
-/* In gcc, use __builtin_expect to minimize impact of checks */
-#if !INSECURE
-#if defined(__GNUC__) && __GNUC__ >= 3
-#define RTCHECK(e) __builtin_expect(e, 1)
-#else /* GNUC */
-#define RTCHECK(e) (e)
-#endif /* GNUC */
-#else /* !INSECURE */
-#define RTCHECK(e) (1)
-#endif /* !INSECURE */
-
-/* macros to set up inuse chunks with or without footers */
-
-#if !FOOTERS
-
-#define mark_inuse_foot(M,p,s)
-
-/* Set cinuse bit and pinuse bit of next chunk */
-#define set_inuse(M,p,s)\
- ((p)->head = (((p)->head & PINUSE_BIT)|s|CINUSE_BIT),\
- ((mchunkptr)(((char*)(p)) + (s)))->head |= PINUSE_BIT)
-
-/* Set cinuse and pinuse of this chunk and pinuse of next chunk */
-#define set_inuse_and_pinuse(M,p,s)\
- ((p)->head = (s|PINUSE_BIT|CINUSE_BIT),\
- ((mchunkptr)(((char*)(p)) + (s)))->head |= PINUSE_BIT)
-
-/* Set size, cinuse and pinuse bit of this chunk */
-#define set_size_and_pinuse_of_inuse_chunk(M, p, s)\
- ((p)->head = (s|PINUSE_BIT|CINUSE_BIT))
-
-#else /* FOOTERS */
-
-/* Set foot of inuse chunk to be xor of mstate and seed */
-#define mark_inuse_foot(M,p,s)\
- (((mchunkptr)((char*)(p) + (s)))->prev_foot = ((size_t)(M) ^ mparams.magic))
-
-#define get_mstate_for(p)\
- ((mstate)(((mchunkptr)((char*)(p) +\
- (chunksize(p))))->prev_foot ^ mparams.magic))
-
-#define set_inuse(M,p,s)\
- ((p)->head = (((p)->head & PINUSE_BIT)|s|CINUSE_BIT),\
- (((mchunkptr)(((char*)(p)) + (s)))->head |= PINUSE_BIT), \
- mark_inuse_foot(M,p,s))
-
-#define set_inuse_and_pinuse(M,p,s)\
- ((p)->head = (s|PINUSE_BIT|CINUSE_BIT),\
- (((mchunkptr)(((char*)(p)) + (s)))->head |= PINUSE_BIT),\
- mark_inuse_foot(M,p,s))
-
-#define set_size_and_pinuse_of_inuse_chunk(M, p, s)\
- ((p)->head = (s|PINUSE_BIT|CINUSE_BIT),\
- mark_inuse_foot(M, p, s))
-
-#endif /* !FOOTERS */
-
-/* ---------------------------- setting mparams -------------------------- */
-
-/* Initialize mparams */
-static int init_mparams(void) {
-#ifdef NEED_GLOBAL_LOCK_INIT
- if (malloc_global_mutex_status <= 0)
- init_malloc_global_mutex();
-#endif
-
- ACQUIRE_MALLOC_GLOBAL_LOCK();
- if (mparams.magic == 0) {
- size_t magic;
- size_t psize;
- size_t gsize;
-
-#ifndef WIN32
- psize = malloc_getpagesize;
- gsize = ((DEFAULT_GRANULARITY != 0)? DEFAULT_GRANULARITY : psize);
-#else /* WIN32 */
- {
- SYSTEM_INFO system_info;
- GetSystemInfo(&system_info);
- psize = system_info.dwPageSize;
- gsize = ((DEFAULT_GRANULARITY != 0)?
- DEFAULT_GRANULARITY : system_info.dwAllocationGranularity);
- }
-#endif /* WIN32 */
-
- /* Sanity-check configuration:
- size_t must be unsigned and as wide as pointer type.
- ints must be at least 4 bytes.
- alignment must be at least 8.
- Alignment, min chunk size, and page size must all be powers of 2.
- */
- if ((sizeof(size_t) != sizeof(char*)) ||
- (MAX_SIZE_T < MIN_CHUNK_SIZE) ||
- (sizeof(int) < 4) ||
- (MALLOC_ALIGNMENT < (size_t)8U) ||
- ((MALLOC_ALIGNMENT & (MALLOC_ALIGNMENT-SIZE_T_ONE)) != 0) ||
- ((MCHUNK_SIZE & (MCHUNK_SIZE-SIZE_T_ONE)) != 0) ||
- ((gsize & (gsize-SIZE_T_ONE)) != 0) ||
- ((psize & (psize-SIZE_T_ONE)) != 0))
- ABORT;
-
- mparams.granularity = gsize;
- mparams.page_size = psize;
- mparams.mmap_threshold = DEFAULT_MMAP_THRESHOLD;
- mparams.trim_threshold = DEFAULT_TRIM_THRESHOLD;
-#if MORECORE_CONTIGUOUS
- mparams.default_mflags = USE_LOCK_BIT|USE_MMAP_BIT;
-#else /* MORECORE_CONTIGUOUS */
- mparams.default_mflags = USE_LOCK_BIT|USE_MMAP_BIT|USE_NONCONTIGUOUS_BIT;
-#endif /* MORECORE_CONTIGUOUS */
-
-#if !ONLY_MSPACES
- /* Set up lock for main malloc area */
- gm->mflags = mparams.default_mflags;
- (void)INITIAL_LOCK(&gm->mutex);
-#endif
-
-#if (FOOTERS && !INSECURE)
- {
-#if USE_DEV_RANDOM
- int fd;
- unsigned char buf[sizeof(size_t)];
- /* Try to use /dev/urandom, else fall back on using time */
- if ((fd = open("/dev/urandom", O_RDONLY)) >= 0 &&
- read(fd, buf, sizeof(buf)) == sizeof(buf)) {
- magic = *((size_t *) buf);
- close(fd);
- }
- else
-#endif /* USE_DEV_RANDOM */
-#ifdef WIN32
- magic = (size_t)(GetTickCount() ^ (size_t)0x55555555U);
-#else
- magic = (size_t)(time(0) ^ (size_t)0x55555555U);
-#endif
- magic |= (size_t)8U; /* ensure nonzero */
- magic &= ~(size_t)7U; /* improve chances of fault for bad values */
- }
-#else /* (FOOTERS && !INSECURE) */
- magic = (size_t)0x58585858U;
-#endif /* (FOOTERS && !INSECURE) */
-
- mparams.magic = magic;
- }
-
- RELEASE_MALLOC_GLOBAL_LOCK();
- return 1;
-}
-
-/* support for mallopt */
-static int change_mparam(int param_number, int value) {
- size_t val = (value == -1)? MAX_SIZE_T : (size_t)value;
- ensure_initialization();
- switch(param_number) {
- case M_TRIM_THRESHOLD:
- mparams.trim_threshold = val;
- return 1;
- case M_GRANULARITY:
- if (val >= mparams.page_size && ((val & (val-1)) == 0)) {
- mparams.granularity = val;
- return 1;
- }
- else
- return 0;
- case M_MMAP_THRESHOLD:
- mparams.mmap_threshold = val;
- return 1;
- default:
- return 0;
- }
-}
-
-#if DEBUG
-/* ------------------------- Debugging Support --------------------------- */
-
-/* Check properties of any chunk, whether free, inuse, mmapped etc */
-static void do_check_any_chunk(mstate m, mchunkptr p) {
- assert((is_aligned(chunk2mem(p))) || (p->head == FENCEPOST_HEAD));
- assert(ok_address(m, p));
-}
-
-/* Check properties of top chunk */
-static void do_check_top_chunk(mstate m, mchunkptr p) {
- msegmentptr sp = segment_holding(m, (char*)p);
- size_t sz = p->head & ~INUSE_BITS; /* third-lowest bit can be set! */
- assert(sp != 0);
- assert((is_aligned(chunk2mem(p))) || (p->head == FENCEPOST_HEAD));
- assert(ok_address(m, p));
- assert(sz == m->topsize);
- assert(sz > 0);
- assert(sz == ((sp->base + sp->size) - (char*)p) - TOP_FOOT_SIZE);
- assert(pinuse(p));
- assert(!pinuse(chunk_plus_offset(p, sz)));
-}
-
-/* Check properties of (inuse) mmapped chunks */
-static void do_check_mmapped_chunk(mstate m, mchunkptr p) {
- size_t sz = chunksize(p);
- size_t len = (sz + (p->prev_foot & ~IS_MMAPPED_BIT) + MMAP_FOOT_PAD);
- assert(is_mmapped(p));
- assert(use_mmap(m));
- assert((is_aligned(chunk2mem(p))) || (p->head == FENCEPOST_HEAD));
- assert(ok_address(m, p));
- assert(!is_small(sz));
- assert((len & (mparams.page_size-SIZE_T_ONE)) == 0);
- assert(chunk_plus_offset(p, sz)->head == FENCEPOST_HEAD);
- assert(chunk_plus_offset(p, sz+SIZE_T_SIZE)->head == 0);
-}
-
-/* Check properties of inuse chunks */
-static void do_check_inuse_chunk(mstate m, mchunkptr p) {
- do_check_any_chunk(m, p);
- assert(cinuse(p));
- assert(next_pinuse(p));
- /* If not pinuse and not mmapped, previous chunk has OK offset */
- assert(is_mmapped(p) || pinuse(p) || next_chunk(prev_chunk(p)) == p);
- if (is_mmapped(p))
- do_check_mmapped_chunk(m, p);
-}
-
-/* Check properties of free chunks */
-static void do_check_free_chunk(mstate m, mchunkptr p) {
- size_t sz = chunksize(p);
- mchunkptr next = chunk_plus_offset(p, sz);
- do_check_any_chunk(m, p);
- assert(!cinuse(p));
- assert(!next_pinuse(p));
- assert (!is_mmapped(p));
- if (p != m->dv && p != m->top) {
- if (sz >= MIN_CHUNK_SIZE) {
- assert((sz & CHUNK_ALIGN_MASK) == 0);
- assert(is_aligned(chunk2mem(p)));
- assert(next->prev_foot == sz);
- assert(pinuse(p));
- assert (next == m->top || cinuse(next));
- assert(p->fd->bk == p);
- assert(p->bk->fd == p);
- }
- else /* markers are always of size SIZE_T_SIZE */
- assert(sz == SIZE_T_SIZE);
- }
-}
-
-/* Check properties of malloced chunks at the point they are malloced */
-static void do_check_malloced_chunk(mstate m, void* mem, size_t s) {
- if (mem != 0) {
- mchunkptr p = mem2chunk(mem);
- size_t sz = p->head & ~(PINUSE_BIT|CINUSE_BIT);
- do_check_inuse_chunk(m, p);
- assert((sz & CHUNK_ALIGN_MASK) == 0);
- assert(sz >= MIN_CHUNK_SIZE);
- assert(sz >= s);
- /* unless mmapped, size is less than MIN_CHUNK_SIZE more than request */
- assert(is_mmapped(p) || sz < (s + MIN_CHUNK_SIZE));
- }
-}
-
-/* Check a tree and its subtrees. */
-static void do_check_tree(mstate m, tchunkptr t) {
- tchunkptr head = 0;
- tchunkptr u = t;
- bindex_t tindex = t->index;
- size_t tsize = chunksize(t);
- bindex_t idx;
- compute_tree_index(tsize, idx);
- assert(tindex == idx);
- assert(tsize >= MIN_LARGE_SIZE);
- assert(tsize >= minsize_for_tree_index(idx));
- assert((idx == NTREEBINS-1) || (tsize < minsize_for_tree_index((idx+1))));
-
- do { /* traverse through chain of same-sized nodes */
- do_check_any_chunk(m, ((mchunkptr)u));
- assert(u->index == tindex);
- assert(chunksize(u) == tsize);
- assert(!cinuse(u));
- assert(!next_pinuse(u));
- assert(u->fd->bk == u);
- assert(u->bk->fd == u);
- if (u->parent == 0) {
- assert(u->child[0] == 0);
- assert(u->child[1] == 0);
- }
- else {
- assert(head == 0); /* only one node on chain has parent */
- head = u;
- assert(u->parent != u);
- assert (u->parent->child[0] == u ||
- u->parent->child[1] == u ||
- *((tbinptr*)(u->parent)) == u);
- if (u->child[0] != 0) {
- assert(u->child[0]->parent == u);
- assert(u->child[0] != u);
- do_check_tree(m, u->child[0]);
- }
- if (u->child[1] != 0) {
- assert(u->child[1]->parent == u);
- assert(u->child[1] != u);
- do_check_tree(m, u->child[1]);
- }
- if (u->child[0] != 0 && u->child[1] != 0) {
- assert(chunksize(u->child[0]) < chunksize(u->child[1]));
- }
- }
- u = u->fd;
- } while (u != t);
- assert(head != 0);
-}
-
-/* Check all the chunks in a treebin. */
-static void do_check_treebin(mstate m, bindex_t i) {
- tbinptr* tb = treebin_at(m, i);
- tchunkptr t = *tb;
- int empty = (m->treemap & (1U << i)) == 0;
- if (t == 0)
- assert(empty);
- if (!empty)
- do_check_tree(m, t);
-}
-
-/* Check all the chunks in a smallbin. */
-static void do_check_smallbin(mstate m, bindex_t i) {
- sbinptr b = smallbin_at(m, i);
- mchunkptr p = b->bk;
- unsigned int empty = (m->smallmap & (1U << i)) == 0;
- if (p == b)
- assert(empty);
- if (!empty) {
- for (; p != b; p = p->bk) {
- size_t size = chunksize(p);
- mchunkptr q;
- /* each chunk claims to be free */
- do_check_free_chunk(m, p);
- /* chunk belongs in bin */
- assert(small_index(size) == i);
- assert(p->bk == b || chunksize(p->bk) == chunksize(p));
- /* chunk is followed by an inuse chunk */
- q = next_chunk(p);
- if (q->head != FENCEPOST_HEAD)
- do_check_inuse_chunk(m, q);
- }
- }
-}
-
-/* Find x in a bin. Used in other check functions. */
-static int bin_find(mstate m, mchunkptr x) {
- size_t size = chunksize(x);
- if (is_small(size)) {
- bindex_t sidx = small_index(size);
- sbinptr b = smallbin_at(m, sidx);
- if (smallmap_is_marked(m, sidx)) {
- mchunkptr p = b;
- do {
- if (p == x)
- return 1;
- } while ((p = p->fd) != b);
- }
- }
- else {
- bindex_t tidx;
- compute_tree_index(size, tidx);
- if (treemap_is_marked(m, tidx)) {
- tchunkptr t = *treebin_at(m, tidx);
- size_t sizebits = size << leftshift_for_tree_index(tidx);
- while (t != 0 && chunksize(t) != size) {
- t = t->child[(sizebits >> (SIZE_T_BITSIZE-SIZE_T_ONE)) & 1];
- sizebits <<= 1;
- }
- if (t != 0) {
- tchunkptr u = t;
- do {
- if (u == (tchunkptr)x)
- return 1;
- } while ((u = u->fd) != t);
- }
- }
- }
- return 0;
-}
-
-/* Traverse each chunk and check it; return total */
-static size_t traverse_and_check(mstate m) {
- size_t sum = 0;
- if (is_initialized(m)) {
- msegmentptr s = &m->seg;
- sum += m->topsize + TOP_FOOT_SIZE;
- while (s != 0) {
- mchunkptr q = align_as_chunk(s->base);
- mchunkptr lastq = 0;
- assert(pinuse(q));
- while (segment_holds(s, q) &&
- q != m->top && q->head != FENCEPOST_HEAD) {
- sum += chunksize(q);
- if (cinuse(q)) {
- assert(!bin_find(m, q));
- do_check_inuse_chunk(m, q);
- }
- else {
- assert(q == m->dv || bin_find(m, q));
- assert(lastq == 0 || cinuse(lastq)); /* Not 2 consecutive free */
- do_check_free_chunk(m, q);
- }
- lastq = q;
- q = next_chunk(q);
- }
- s = s->next;
- }
- }
- return sum;
-}
-
-/* Check all properties of malloc_state. */
-static void do_check_malloc_state(mstate m) {
- bindex_t i;
- size_t total;
- /* check bins */
- for (i = 0; i < NSMALLBINS; ++i)
- do_check_smallbin(m, i);
- for (i = 0; i < NTREEBINS; ++i)
- do_check_treebin(m, i);
-
- if (m->dvsize != 0) { /* check dv chunk */
- do_check_any_chunk(m, m->dv);
- assert(m->dvsize == chunksize(m->dv));
- assert(m->dvsize >= MIN_CHUNK_SIZE);
- assert(bin_find(m, m->dv) == 0);
- }
-
- if (m->top != 0) { /* check top chunk */
- do_check_top_chunk(m, m->top);
- /*assert(m->topsize == chunksize(m->top)); redundant */
- assert(m->topsize > 0);
- assert(bin_find(m, m->top) == 0);
- }
-
- total = traverse_and_check(m);
- assert(total <= m->footprint);
- assert(m->footprint <= m->max_footprint);
-}
-#endif /* DEBUG */
-
-/* ----------------------------- statistics ------------------------------ */
-
-#if !NO_MALLINFO
-static struct mallinfo internal_mallinfo(mstate m) {
- struct mallinfo nm = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 };
- ensure_initialization();
- if (!PREACTION(m)) {
- check_malloc_state(m);
- if (is_initialized(m)) {
- size_t nfree = SIZE_T_ONE; /* top always free */
- size_t mfree = m->topsize + TOP_FOOT_SIZE;
- size_t sum = mfree;
- msegmentptr s = &m->seg;
- while (s != 0) {
- mchunkptr q = align_as_chunk(s->base);
- while (segment_holds(s, q) &&
- q != m->top && q->head != FENCEPOST_HEAD) {
- size_t sz = chunksize(q);
- sum += sz;
- if (!cinuse(q)) {
- mfree += sz;
- ++nfree;
- }
- q = next_chunk(q);
- }
- s = s->next;
- }
-
- nm.arena = sum;
- nm.ordblks = nfree;
- nm.hblkhd = m->footprint - sum;
- nm.usmblks = m->max_footprint;
- nm.uordblks = m->footprint - mfree;
- nm.fordblks = mfree;
- nm.keepcost = m->topsize;
- }
-
- POSTACTION(m);
- }
- return nm;
-}
-#endif /* !NO_MALLINFO */
-
-static void internal_malloc_stats(mstate m) {
- ensure_initialization();
- if (!PREACTION(m)) {
- size_t maxfp = 0;
- size_t fp = 0;
- size_t used = 0;
- check_malloc_state(m);
- if (is_initialized(m)) {
- msegmentptr s = &m->seg;
- maxfp = m->max_footprint;
- fp = m->footprint;
- used = fp - (m->topsize + TOP_FOOT_SIZE);
-
- while (s != 0) {
- mchunkptr q = align_as_chunk(s->base);
- while (segment_holds(s, q) &&
- q != m->top && q->head != FENCEPOST_HEAD) {
- if (!cinuse(q))
- used -= chunksize(q);
- q = next_chunk(q);
- }
- s = s->next;
- }
- }
-
- fprintf(stderr, "max system bytes = %10lu\n", (unsigned long)(maxfp));
- fprintf(stderr, "system bytes = %10lu\n", (unsigned long)(fp));
- fprintf(stderr, "in use bytes = %10lu\n", (unsigned long)(used));
-
- POSTACTION(m);
- }
-}
-
-/* ----------------------- Operations on smallbins ----------------------- */
-
-/*
- Various forms of linking and unlinking are defined as macros. Even
- the ones for trees, which are very long but have very short typical
- paths. This is ugly but reduces reliance on inlining support of
- compilers.
-*/
-
-/* Link a free chunk into a smallbin */
-#define insert_small_chunk(M, P, S) {\
- bindex_t I = small_index(S);\
- mchunkptr B = smallbin_at(M, I);\
- mchunkptr F = B;\
- assert(S >= MIN_CHUNK_SIZE);\
- if (!smallmap_is_marked(M, I))\
- mark_smallmap(M, I);\
- else if (RTCHECK(ok_address(M, B->fd)))\
- F = B->fd;\
- else {\
- CORRUPTION_ERROR_ACTION(M);\
- }\
- B->fd = P;\
- F->bk = P;\
- P->fd = F;\
- P->bk = B;\
-}
-
-/* Unlink a chunk from a smallbin */
-#define unlink_small_chunk(M, P, S) {\
- mchunkptr F = P->fd;\
- mchunkptr B = P->bk;\
- bindex_t I = small_index(S);\
- assert(P != B);\
- assert(P != F);\
- assert(chunksize(P) == small_index2size(I));\
- if (F == B)\
- clear_smallmap(M, I);\
- else if (RTCHECK((F == smallbin_at(M,I) || ok_address(M, F)) &&\
- (B == smallbin_at(M,I) || ok_address(M, B)))) {\
- F->bk = B;\
- B->fd = F;\
- }\
- else {\
- CORRUPTION_ERROR_ACTION(M);\
- }\
-}
-
-/* Unlink the first chunk from a smallbin */
-#define unlink_first_small_chunk(M, B, P, I) {\
- mchunkptr F = P->fd;\
- assert(P != B);\
- assert(P != F);\
- assert(chunksize(P) == small_index2size(I));\
- if (B == F)\
- clear_smallmap(M, I);\
- else if (RTCHECK(ok_address(M, F))) {\
- B->fd = F;\
- F->bk = B;\
- }\
- else {\
- CORRUPTION_ERROR_ACTION(M);\
- }\
-}
-
-
-
-/* Replace dv node, binning the old one */
-/* Used only when dvsize known to be small */
-#define replace_dv(M, P, S) {\
- size_t DVS = M->dvsize;\
- if (DVS != 0) {\
- mchunkptr DV = M->dv;\
- assert(is_small(DVS));\
- insert_small_chunk(M, DV, DVS);\
- }\
- M->dvsize = S;\
- M->dv = P;\
-}
-
-/* ------------------------- Operations on trees ------------------------- */
-
-/* Insert chunk into tree */
-#define insert_large_chunk(M, X, S) {\
- tbinptr* H;\
- bindex_t I;\
- compute_tree_index(S, I);\
- H = treebin_at(M, I);\
- X->index = I;\
- X->child[0] = X->child[1] = 0;\
- if (!treemap_is_marked(M, I)) {\
- mark_treemap(M, I);\
- *H = X;\
- X->parent = (tchunkptr)H;\
- X->fd = X->bk = X;\
- }\
- else {\
- tchunkptr T = *H;\
- size_t K = S << leftshift_for_tree_index(I);\
- for (;;) {\
- if (chunksize(T) != S) {\
- tchunkptr* C = &(T->child[(K >> (SIZE_T_BITSIZE-SIZE_T_ONE)) & 1]);\
- K <<= 1;\
- if (*C != 0)\
- T = *C;\
- else if (RTCHECK(ok_address(M, C))) {\
- *C = X;\
- X->parent = T;\
- X->fd = X->bk = X;\
- break;\
- }\
- else {\
- CORRUPTION_ERROR_ACTION(M);\
- break;\
- }\
- }\
- else {\
- tchunkptr F = T->fd;\
- if (RTCHECK(ok_address(M, T) && ok_address(M, F))) {\
- T->fd = F->bk = X;\
- X->fd = F;\
- X->bk = T;\
- X->parent = 0;\
- break;\
- }\
- else {\
- CORRUPTION_ERROR_ACTION(M);\
- break;\
- }\
- }\
- }\
- }\
-}
-
-/*
- Unlink steps:
-
- 1. If x is a chained node, unlink it from its same-sized fd/bk links
- and choose its bk node as its replacement.
- 2. If x was the last node of its size, but not a leaf node, it must
- be replaced with a leaf node (not merely one with an open left or
- right), to make sure that lefts and rights of descendants
- correspond properly to bit masks. We use the rightmost descendant
- of x. We could use any other leaf, but this is easy to locate and
- tends to counteract removal of leftmosts elsewhere, and so keeps
- paths shorter than minimally guaranteed. This doesn't loop much
- because on average a node in a tree is near the bottom.
- 3. If x is the base of a chain (i.e., has parent links) relink
- x's parent and children to x's replacement (or null if none).
-*/
-
-#define unlink_large_chunk(M, X) {\
- tchunkptr XP = X->parent;\
- tchunkptr R;\
- if (X->bk != X) {\
- tchunkptr F = X->fd;\
- R = X->bk;\
- if (RTCHECK(ok_address(M, F))) {\
- F->bk = R;\
- R->fd = F;\
- }\
- else {\
- CORRUPTION_ERROR_ACTION(M);\
- }\
- }\
- else {\
- tchunkptr* RP;\
- if (((R = *(RP = &(X->child[1]))) != 0) ||\
- ((R = *(RP = &(X->child[0]))) != 0)) {\
- tchunkptr* CP;\
- while ((*(CP = &(R->child[1])) != 0) ||\
- (*(CP = &(R->child[0])) != 0)) {\
- R = *(RP = CP);\
- }\
- if (RTCHECK(ok_address(M, RP)))\
- *RP = 0;\
- else {\
- CORRUPTION_ERROR_ACTION(M);\
- }\
- }\
- }\
- if (XP != 0) {\
- tbinptr* H = treebin_at(M, X->index);\
- if (X == *H) {\
- if ((*H = R) == 0) \
- clear_treemap(M, X->index);\
- }\
- else if (RTCHECK(ok_address(M, XP))) {\
- if (XP->child[0] == X) \
- XP->child[0] = R;\
- else \
- XP->child[1] = R;\
- }\
- else\
- CORRUPTION_ERROR_ACTION(M);\
- if (R != 0) {\
- if (RTCHECK(ok_address(M, R))) {\
- tchunkptr C0, C1;\
- R->parent = XP;\
- if ((C0 = X->child[0]) != 0) {\
- if (RTCHECK(ok_address(M, C0))) {\
- R->child[0] = C0;\
- C0->parent = R;\
- }\
- else\
- CORRUPTION_ERROR_ACTION(M);\
- }\
- if ((C1 = X->child[1]) != 0) {\
- if (RTCHECK(ok_address(M, C1))) {\
- R->child[1] = C1;\
- C1->parent = R;\
- }\
- else\
- CORRUPTION_ERROR_ACTION(M);\
- }\
- }\
- else\
- CORRUPTION_ERROR_ACTION(M);\
- }\
- }\
-}
-
-/* Relays to large vs small bin operations */
-
-#define insert_chunk(M, P, S)\
- if (is_small(S)) insert_small_chunk(M, P, S)\
- else { tchunkptr TP = (tchunkptr)(P); insert_large_chunk(M, TP, S); }
-
-#define unlink_chunk(M, P, S)\
- if (is_small(S)) unlink_small_chunk(M, P, S)\
- else { tchunkptr TP = (tchunkptr)(P); unlink_large_chunk(M, TP); }
-
-
-/* Relays to internal calls to malloc/free from realloc, memalign etc */
-
-#if ONLY_MSPACES
-#define internal_malloc(m, b) mspace_malloc(m, b)
-#define internal_free(m, mem) mspace_free(m,mem);
-#else /* ONLY_MSPACES */
-#if MSPACES
-#define internal_malloc(m, b)\
- (m == gm)? dlmalloc(b) : mspace_malloc(m, b)
-#define internal_free(m, mem)\
- if (m == gm) dlfree(mem); else mspace_free(m,mem);
-#else /* MSPACES */
-#define internal_malloc(m, b) dlmalloc(b)
-#define internal_free(m, mem) dlfree(mem)
-#endif /* MSPACES */
-#endif /* ONLY_MSPACES */
-
-/* ----------------------- Direct-mmapping chunks ----------------------- */
-
-/*
- Directly mmapped chunks are set up with an offset to the start of
- the mmapped region stored in the prev_foot field of the chunk. This
- allows reconstruction of the required argument to MUNMAP when freed,
- and also allows adjustment of the returned chunk to meet alignment
- requirements (especially in memalign). There is also enough space
- allocated to hold a fake next chunk of size SIZE_T_SIZE to maintain
- the PINUSE bit so frees can be checked.
-*/
-
-/* Malloc using mmap */
-static void* mmap_alloc(mstate m, size_t nb) {
- size_t mmsize = mmap_align(nb + SIX_SIZE_T_SIZES + CHUNK_ALIGN_MASK);
- if (mmsize > nb) { /* Check for wrap around 0 */
- char* mm = (char*)(CALL_DIRECT_MMAP(mmsize));
- if (mm != CMFAIL) {
- size_t offset = align_offset(chunk2mem(mm));
- size_t psize = mmsize - offset - MMAP_FOOT_PAD;
- mchunkptr p = (mchunkptr)(mm + offset);
- p->prev_foot = offset | IS_MMAPPED_BIT;
- (p)->head = (psize|CINUSE_BIT);
- mark_inuse_foot(m, p, psize);
- chunk_plus_offset(p, psize)->head = FENCEPOST_HEAD;
- chunk_plus_offset(p, psize+SIZE_T_SIZE)->head = 0;
-
- if (mm < m->least_addr)
- m->least_addr = mm;
- if ((m->footprint += mmsize) > m->max_footprint)
- m->max_footprint = m->footprint;
- assert(is_aligned(chunk2mem(p)));
- check_mmapped_chunk(m, p);
- return chunk2mem(p);
- }
- }
- return 0;
-}
-
-/* Realloc using mmap */
-static mchunkptr mmap_resize(mstate m, mchunkptr oldp, size_t nb) {
- size_t oldsize = chunksize(oldp);
- if (is_small(nb)) /* Can't shrink mmap regions below small size */
- return 0;
- /* Keep old chunk if big enough but not too big */
- if (oldsize >= nb + SIZE_T_SIZE &&
- (oldsize - nb) <= (mparams.granularity << 1))
- return oldp;
- else {
- size_t offset = oldp->prev_foot & ~IS_MMAPPED_BIT;
- size_t oldmmsize = oldsize + offset + MMAP_FOOT_PAD;
- size_t newmmsize = mmap_align(nb + SIX_SIZE_T_SIZES + CHUNK_ALIGN_MASK);
- char* cp = (char*)CALL_MREMAP((char*)oldp - offset,
- oldmmsize, newmmsize, 1);
- if (cp != CMFAIL) {
- mchunkptr newp = (mchunkptr)(cp + offset);
- size_t psize = newmmsize - offset - MMAP_FOOT_PAD;
- newp->head = (psize|CINUSE_BIT);
- mark_inuse_foot(m, newp, psize);
- chunk_plus_offset(newp, psize)->head = FENCEPOST_HEAD;
- chunk_plus_offset(newp, psize+SIZE_T_SIZE)->head = 0;
-
- if (cp < m->least_addr)
- m->least_addr = cp;
- if ((m->footprint += newmmsize - oldmmsize) > m->max_footprint)
- m->max_footprint = m->footprint;
- check_mmapped_chunk(m, newp);
- return newp;
- }
- }
- return 0;
-}
-
-/* -------------------------- mspace management -------------------------- */
-
-/* Initialize top chunk and its size */
-static void init_top(mstate m, mchunkptr p, size_t psize) {
- /* Ensure alignment */
- size_t offset = align_offset(chunk2mem(p));
- p = (mchunkptr)((char*)p + offset);
- psize -= offset;
-
- m->top = p;
- m->topsize = psize;
- p->head = psize | PINUSE_BIT;
- /* set size of fake trailing chunk holding overhead space only once */
- chunk_plus_offset(p, psize)->head = TOP_FOOT_SIZE;
- m->trim_check = mparams.trim_threshold; /* reset on each update */
-}
-
-/* Initialize bins for a new mstate that is otherwise zeroed out */
-static void init_bins(mstate m) {
- /* Establish circular links for smallbins */
- bindex_t i;
- for (i = 0; i < NSMALLBINS; ++i) {
- sbinptr bin = smallbin_at(m,i);
- bin->fd = bin->bk = bin;
- }
-}
-
-#if PROCEED_ON_ERROR
-
-/* default corruption action */
-static void reset_on_error(mstate m) {
- int i;
- ++malloc_corruption_error_count;
- /* Reinitialize fields to forget about all memory */
- m->smallbins = m->treebins = 0;
- m->dvsize = m->topsize = 0;
- m->seg.base = 0;
- m->seg.size = 0;
- m->seg.next = 0;
- m->top = m->dv = 0;
- for (i = 0; i < NTREEBINS; ++i)
- *treebin_at(m, i) = 0;
- init_bins(m);
-}
-#endif /* PROCEED_ON_ERROR */
-
-/* Allocate chunk and prepend remainder with chunk in successor base. */
-static void* prepend_alloc(mstate m, char* newbase, char* oldbase,
- size_t nb) {
- mchunkptr p = align_as_chunk(newbase);
- mchunkptr oldfirst = align_as_chunk(oldbase);
- size_t psize = (char*)oldfirst - (char*)p;
- mchunkptr q = chunk_plus_offset(p, nb);
- size_t qsize = psize - nb;
- set_size_and_pinuse_of_inuse_chunk(m, p, nb);
-
- assert((char*)oldfirst > (char*)q);
- assert(pinuse(oldfirst));
- assert(qsize >= MIN_CHUNK_SIZE);
-
- /* consolidate remainder with first chunk of old base */
- if (oldfirst == m->top) {
- size_t tsize = m->topsize += qsize;
- m->top = q;
- q->head = tsize | PINUSE_BIT;
- check_top_chunk(m, q);
- }
- else if (oldfirst == m->dv) {
- size_t dsize = m->dvsize += qsize;
- m->dv = q;
- set_size_and_pinuse_of_free_chunk(q, dsize);
- }
- else {
- if (!cinuse(oldfirst)) {
- size_t nsize = chunksize(oldfirst);
- unlink_chunk(m, oldfirst, nsize);
- oldfirst = chunk_plus_offset(oldfirst, nsize);
- qsize += nsize;
- }
- set_free_with_pinuse(q, qsize, oldfirst);
- insert_chunk(m, q, qsize);
- check_free_chunk(m, q);
- }
-
- check_malloced_chunk(m, chunk2mem(p), nb);
- return chunk2mem(p);
-}
-
-/* Add a segment to hold a new noncontiguous region */
-static void add_segment(mstate m, char* tbase, size_t tsize, flag_t mmapped) {
- /* Determine locations and sizes of segment, fenceposts, old top */
- char* old_top = (char*)m->top;
- msegmentptr oldsp = segment_holding(m, old_top);
- char* old_end = oldsp->base + oldsp->size;
- size_t ssize = pad_request(sizeof(struct malloc_segment));
- char* rawsp = old_end - (ssize + FOUR_SIZE_T_SIZES + CHUNK_ALIGN_MASK);
- size_t offset = align_offset(chunk2mem(rawsp));
- char* asp = rawsp + offset;
- char* csp = (asp < (old_top + MIN_CHUNK_SIZE))? old_top : asp;
- mchunkptr sp = (mchunkptr)csp;
- msegmentptr ss = (msegmentptr)(chunk2mem(sp));
- mchunkptr tnext = chunk_plus_offset(sp, ssize);
- mchunkptr p = tnext;
- int nfences = 0;
-
- /* reset top to new space */
- init_top(m, (mchunkptr)tbase, tsize - TOP_FOOT_SIZE);
-
- /* Set up segment record */
- assert(is_aligned(ss));
- set_size_and_pinuse_of_inuse_chunk(m, sp, ssize);
- *ss = m->seg; /* Push current record */
- m->seg.base = tbase;
- m->seg.size = tsize;
- m->seg.sflags = mmapped;
- m->seg.next = ss;
-
- /* Insert trailing fenceposts */
- for (;;) {
- mchunkptr nextp = chunk_plus_offset(p, SIZE_T_SIZE);
- p->head = FENCEPOST_HEAD;
- ++nfences;
- if ((char*)(&(nextp->head)) < old_end)
- p = nextp;
- else
- break;
- }
- assert(nfences >= 2);
-
- /* Insert the rest of old top into a bin as an ordinary free chunk */
- if (csp != old_top) {
- mchunkptr q = (mchunkptr)old_top;
- size_t psize = csp - old_top;
- mchunkptr tn = chunk_plus_offset(q, psize);
- set_free_with_pinuse(q, psize, tn);
- insert_chunk(m, q, psize);
- }
-
- check_top_chunk(m, m->top);
-}
-
/* -------------------------- System allocation -------------------------- */
/* Get memory from system using MORECORE or MMAP */
--
gitgitgadget
^ permalink raw reply related
* [PATCH v3 4/6] to be squashed into 3/6 (chunk 1 of 3)
From: Johannes Schindelin via GitGitGadget @ 2026-05-08 12:50 UTC (permalink / raw)
To: git; +Cc: Patrick Steinhardt, Johannes Schindelin, Johannes Schindelin
In-Reply-To: <pull.2104.v3.git.1778244661.gitgitgadget@gmail.com>
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Assisted-by: Opus 4.7
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
compat/nedmalloc/malloc.c.h | 2235 -----------------------------------
1 file changed, 2235 deletions(-)
diff --git a/compat/nedmalloc/malloc.c.h b/compat/nedmalloc/malloc.c.h
index e0c567586c..b4fb8c8846 100644
--- a/compat/nedmalloc/malloc.c.h
+++ b/compat/nedmalloc/malloc.c.h
@@ -1,2238 +1,3 @@
-/*
- This is a version (aka dlmalloc) of malloc/free/realloc written by
- Doug Lea and released to the public domain, as explained at
- http://creativecommons.org/licenses/publicdomain. Send questions,
- comments, complaints, performance data, etc to dl@cs.oswego.edu
-
-* Version pre-2.8.4 Mon Nov 27 11:22:37 2006 (dl at gee)
-
- Note: There may be an updated version of this malloc obtainable at
- ftp://gee.cs.oswego.edu/pub/misc/malloc.c
- Check before installing!
-
-* Quickstart
-
- This library is all in one file to simplify the most common usage:
- ftp it, compile it (-O3), and link it into another program. All of
- the compile-time options default to reasonable values for use on
- most platforms. You might later want to step through various
- compile-time and dynamic tuning options.
-
- For convenience, an include file for code using this malloc is at:
- ftp://gee.cs.oswego.edu/pub/misc/malloc-2.8.4.h
- You don't really need this .h file unless you call functions not
- defined in your system include files. The .h file contains only the
- excerpts from this file needed for using this malloc on ANSI C/C++
- systems, so long as you haven't changed compile-time options about
- naming and tuning parameters. If you do, then you can create your
- own malloc.h that does include all settings by cutting at the point
- indicated below. Note that you may already by default be using a C
- library containing a malloc that is based on some version of this
- malloc (for example in linux). You might still want to use the one
- in this file to customize settings or to avoid overheads associated
- with library versions.
-
-* Vital statistics:
-
- Supported pointer/size_t representation: 4 or 8 bytes
- size_t MUST be an unsigned type of the same width as
- pointers. (If you are using an ancient system that declares
- size_t as a signed type, or need it to be a different width
- than pointers, you can use a previous release of this malloc
- (e.g. 2.7.2) supporting these.)
-
- Alignment: 8 bytes (default)
- This suffices for nearly all current machines and C compilers.
- However, you can define MALLOC_ALIGNMENT to be wider than this
- if necessary (up to 128bytes), at the expense of using more space.
-
- Minimum overhead per allocated chunk: 4 or 8 bytes (if 4byte sizes)
- 8 or 16 bytes (if 8byte sizes)
- Each malloced chunk has a hidden word of overhead holding size
- and status information, and additional cross-check word
- if FOOTERS is defined.
-
- Minimum allocated size: 4-byte ptrs: 16 bytes (including overhead)
- 8-byte ptrs: 32 bytes (including overhead)
-
- Even a request for zero bytes (i.e., malloc(0)) returns a
- pointer to something of the minimum allocatable size.
- The maximum overhead wastage (i.e., number of extra bytes
- allocated than were requested in malloc) is less than or equal
- to the minimum size, except for requests >= mmap_threshold that
- are serviced via mmap(), where the worst case wastage is about
- 32 bytes plus the remainder from a system page (the minimal
- mmap unit); typically 4096 or 8192 bytes.
-
- Security: static-safe; optionally more or less
- The "security" of malloc refers to the ability of malicious
- code to accentuate the effects of errors (for example, freeing
- space that is not currently malloc'ed or overwriting past the
- ends of chunks) in code that calls malloc. This malloc
- guarantees not to modify any memory locations below the base of
- heap, i.e., static variables, even in the presence of usage
- errors. The routines additionally detect most improper frees
- and reallocs. All this holds as long as the static bookkeeping
- for malloc itself is not corrupted by some other means. This
- is only one aspect of security -- these checks do not, and
- cannot, detect all possible programming errors.
-
- If FOOTERS is defined nonzero, then each allocated chunk
- carries an additional check word to verify that it was malloced
- from its space. These check words are the same within each
- execution of a program using malloc, but differ across
- executions, so externally crafted fake chunks cannot be
- freed. This improves security by rejecting frees/reallocs that
- could corrupt heap memory, in addition to the checks preventing
- writes to statics that are always on. This may further improve
- security at the expense of time and space overhead. (Note that
- FOOTERS may also be worth using with MSPACES.)
-
- By default detected errors cause the program to abort (calling
- "abort()"). You can override this to instead proceed past
- errors by defining PROCEED_ON_ERROR. In this case, a bad free
- has no effect, and a malloc that encounters a bad address
- caused by user overwrites will ignore the bad address by
- dropping pointers and indices to all known memory. This may
- be appropriate for programs that should continue if at all
- possible in the face of programming errors, although they may
- run out of memory because dropped memory is never reclaimed.
-
- If you don't like either of these options, you can define
- CORRUPTION_ERROR_ACTION and USAGE_ERROR_ACTION to do anything
- else. And if you are sure that your program using malloc has
- no errors or vulnerabilities, you can define INSECURE to 1,
- which might (or might not) provide a small performance improvement.
-
- Thread-safety: NOT thread-safe unless USE_LOCKS defined
- When USE_LOCKS is defined, each public call to malloc, free,
- etc is surrounded with either a pthread mutex or a win32
- spinlock (depending on WIN32). This is not especially fast, and
- can be a major bottleneck. It is designed only to provide
- minimal protection in concurrent environments, and to provide a
- basis for extensions. If you are using malloc in a concurrent
- program, consider instead using nedmalloc
- (http://www.nedprod.com/programs/portable/nedmalloc/) or
- ptmalloc (See http://www.malloc.de), which are derived
- from versions of this malloc.
-
- System requirements: Any combination of MORECORE and/or MMAP/MUNMAP
- This malloc can use unix sbrk or any emulation (invoked using
- the CALL_MORECORE macro) and/or mmap/munmap or any emulation
- (invoked using CALL_MMAP/CALL_MUNMAP) to get and release system
- memory. On most unix systems, it tends to work best if both
- MORECORE and MMAP are enabled. On Win32, it uses emulations
- based on VirtualAlloc. It also uses common C library functions
- like memset.
-
- Compliance: I believe it is compliant with the Single Unix Specification
- (See http://www.unix.org). Also SVID/XPG, ANSI C, and probably
- others as well.
-
-* Overview of algorithms
-
- This is not the fastest, most space-conserving, most portable, or
- most tunable malloc ever written. However it is among the fastest
- while also being among the most space-conserving, portable and
- tunable. Consistent balance across these factors results in a good
- general-purpose allocator for malloc-intensive programs.
-
- In most ways, this malloc is a best-fit allocator. Generally, it
- chooses the best-fitting existing chunk for a request, with ties
- broken in approximately least-recently-used order. (This strategy
- normally maintains low fragmentation.) However, for requests less
- than 256bytes, it deviates from best-fit when there is not an
- exactly fitting available chunk by preferring to use space adjacent
- to that used for the previous small request, as well as by breaking
- ties in approximately most-recently-used order. (These enhance
- locality of series of small allocations.) And for very large requests
- (>= 256Kb by default), it relies on system memory mapping
- facilities, if supported. (This helps avoid carrying around and
- possibly fragmenting memory used only for large chunks.)
-
- All operations (except malloc_stats and mallinfo) have execution
- times that are bounded by a constant factor of the number of bits in
- a size_t, not counting any clearing in calloc or copying in realloc,
- or actions surrounding MORECORE and MMAP that have times
- proportional to the number of non-contiguous regions returned by
- system allocation routines, which is often just 1. In real-time
- applications, you can optionally suppress segment traversals using
- NO_SEGMENT_TRAVERSAL, which assures bounded execution even when
- system allocators return non-contiguous spaces, at the typical
- expense of carrying around more memory and increased fragmentation.
-
- The implementation is not very modular and seriously overuses
- macros. Perhaps someday all C compilers will do as good a job
- inlining modular code as can now be done by brute-force expansion,
- but now, enough of them seem not to.
-
- Some compilers issue a lot of warnings about code that is
- dead/unreachable only on some platforms, and also about intentional
- uses of negation on unsigned types. All known cases of each can be
- ignored.
-
- For a longer but out of date high-level description, see
- http://gee.cs.oswego.edu/dl/html/malloc.html
-
-* MSPACES
- If MSPACES is defined, then in addition to malloc, free, etc.,
- this file also defines mspace_malloc, mspace_free, etc. These
- are versions of malloc routines that take an "mspace" argument
- obtained using create_mspace, to control all internal bookkeeping.
- If ONLY_MSPACES is defined, only these versions are compiled.
- So if you would like to use this allocator for only some allocations,
- and your system malloc for others, you can compile with
- ONLY_MSPACES and then do something like...
- static mspace mymspace = create_mspace(0,0); // for example
- #define mymalloc(bytes) mspace_malloc(mymspace, bytes)
-
- (Note: If you only need one instance of an mspace, you can instead
- use "USE_DL_PREFIX" to relabel the global malloc.)
-
- You can similarly create thread-local allocators by storing
- mspaces as thread-locals. For example:
- static __thread mspace tlms = 0;
- void* tlmalloc(size_t bytes) {
- if (tlms == 0) tlms = create_mspace(0, 0);
- return mspace_malloc(tlms, bytes);
- }
- void tlfree(void* mem) { mspace_free(tlms, mem); }
-
- Unless FOOTERS is defined, each mspace is completely independent.
- You cannot allocate from one and free to another (although
- conformance is only weakly checked, so usage errors are not always
- caught). If FOOTERS is defined, then each chunk carries around a tag
- indicating its originating mspace, and frees are directed to their
- originating spaces.
-
- ------------------------- Compile-time options ---------------------------
-
-Be careful in setting #define values for numerical constants of type
-size_t. On some systems, literal values are not automatically extended
-to size_t precision unless they are explicitly casted. You can also
-use the symbolic values MAX_SIZE_T, SIZE_T_ONE, etc below.
-
-WIN32 default: defined if _WIN32 defined
- Defining WIN32 sets up defaults for MS environment and compilers.
- Otherwise defaults are for unix. Beware that there seem to be some
- cases where this malloc might not be a pure drop-in replacement for
- Win32 malloc: Random-looking failures from Win32 GDI API's (eg;
- SetDIBits()) may be due to bugs in some video driver implementations
- when pixel buffers are malloc()ed, and the region spans more than
- one VirtualAlloc()ed region. Because dlmalloc uses a small (64Kb)
- default granularity, pixel buffers may straddle virtual allocation
- regions more often than when using the Microsoft allocator. You can
- avoid this by using VirtualAlloc() and VirtualFree() for all pixel
- buffers rather than using malloc(). If this is not possible,
- recompile this malloc with a larger DEFAULT_GRANULARITY.
-
-MALLOC_ALIGNMENT default: (size_t)8
- Controls the minimum alignment for malloc'ed chunks. It must be a
- power of two and at least 8, even on machines for which smaller
- alignments would suffice. It may be defined as larger than this
- though. Note however that code and data structures are optimized for
- the case of 8-byte alignment.
-
-MSPACES default: 0 (false)
- If true, compile in support for independent allocation spaces.
- This is only supported if HAVE_MMAP is true.
-
-ONLY_MSPACES default: 0 (false)
- If true, only compile in mspace versions, not regular versions.
-
-USE_LOCKS default: 0 (false)
- Causes each call to each public routine to be surrounded with
- pthread or WIN32 mutex lock/unlock. (If set true, this can be
- overridden on a per-mspace basis for mspace versions.) If set to a
- non-zero value other than 1, locks are used, but their
- implementation is left out, so lock functions must be supplied manually.
-
-USE_SPIN_LOCKS default: 1 iff USE_LOCKS and on x86 using gcc or MSC
- If true, uses custom spin locks for locking. This is currently
- supported only for x86 platforms using gcc or recent MS compilers.
- Otherwise, posix locks or win32 critical sections are used.
-
-FOOTERS default: 0
- If true, provide extra checking and dispatching by placing
- information in the footers of allocated chunks. This adds
- space and time overhead.
-
-INSECURE default: 0
- If true, omit checks for usage errors and heap space overwrites.
-
-USE_DL_PREFIX default: NOT defined
- Causes compiler to prefix all public routines with the string 'dl'.
- This can be useful when you only want to use this malloc in one part
- of a program, using your regular system malloc elsewhere.
-
-ABORT default: defined as abort()
- Defines how to abort on failed checks. On most systems, a failed
- check cannot die with an "assert" or even print an informative
- message, because the underlying print routines in turn call malloc,
- which will fail again. Generally, the best policy is to simply call
- abort(). It's not very useful to do more than this because many
- errors due to overwriting will show up as address faults (null, odd
- addresses etc) rather than malloc-triggered checks, so will also
- abort. Also, most compilers know that abort() does not return, so
- can better optimize code conditionally calling it.
-
-PROCEED_ON_ERROR default: defined as 0 (false)
- Controls whether detected bad addresses cause them to bypassed
- rather than aborting. If set, detected bad arguments to free and
- realloc are ignored. And all bookkeeping information is zeroed out
- upon a detected overwrite of freed heap space, thus losing the
- ability to ever return it from malloc again, but enabling the
- application to proceed. If PROCEED_ON_ERROR is defined, the
- static variable malloc_corruption_error_count is compiled in
- and can be examined to see if errors have occurred. This option
- generates slower code than the default abort policy.
-
-DEBUG default: NOT defined
- The DEBUG setting is mainly intended for people trying to modify
- this code or diagnose problems when porting to new platforms.
- However, it may also be able to better isolate user errors than just
- using runtime checks. The assertions in the check routines spell
- out in more detail the assumptions and invariants underlying the
- algorithms. The checking is fairly extensive, and will slow down
- execution noticeably. Calling malloc_stats or mallinfo with DEBUG
- set will attempt to check every non-mmapped allocated and free chunk
- in the course of computing the summaries.
-
-ABORT_ON_ASSERT_FAILURE default: defined as 1 (true)
- Debugging assertion failures can be nearly impossible if your
- version of the assert macro causes malloc to be called, which will
- lead to a cascade of further failures, blowing the runtime stack.
- ABORT_ON_ASSERT_FAILURE cause assertions failures to call abort(),
- which will usually make debugging easier.
-
-MALLOC_FAILURE_ACTION default: sets errno to ENOMEM, or no-op on win32
- The action to take before "return 0" when malloc fails to be able to
- return memory because there is none available.
-
-HAVE_MORECORE default: 1 (true) unless win32 or ONLY_MSPACES
- True if this system supports sbrk or an emulation of it.
-
-MORECORE default: sbrk
- The name of the sbrk-style system routine to call to obtain more
- memory. See below for guidance on writing custom MORECORE
- functions. The type of the argument to sbrk/MORECORE varies across
- systems. It cannot be size_t, because it supports negative
- arguments, so it is normally the signed type of the same width as
- size_t (sometimes declared as "intptr_t"). It doesn't much matter
- though. Internally, we only call it with arguments less than half
- the max value of a size_t, which should work across all reasonable
- possibilities, although sometimes generating compiler warnings.
-
-MORECORE_CONTIGUOUS default: 1 (true) if HAVE_MORECORE
- If true, take advantage of fact that consecutive calls to MORECORE
- with positive arguments always return contiguous increasing
- addresses. This is true of unix sbrk. It does not hurt too much to
- set it true anyway, since malloc copes with non-contiguities.
- Setting it false when definitely non-contiguous saves time
- and possibly wasted space it would take to discover this though.
-
-MORECORE_CANNOT_TRIM default: NOT defined
- True if MORECORE cannot release space back to the system when given
- negative arguments. This is generally necessary only if you are
- using a hand-crafted MORECORE function that cannot handle negative
- arguments.
-
-NO_SEGMENT_TRAVERSAL default: 0
- If non-zero, suppresses traversals of memory segments
- returned by either MORECORE or CALL_MMAP. This disables
- merging of segments that are contiguous, and selectively
- releasing them to the OS if unused, but bounds execution times.
-
-HAVE_MMAP default: 1 (true)
- True if this system supports mmap or an emulation of it. If so, and
- HAVE_MORECORE is not true, MMAP is used for all system
- allocation. If set and HAVE_MORECORE is true as well, MMAP is
- primarily used to directly allocate very large blocks. It is also
- used as a backup strategy in cases where MORECORE fails to provide
- space from system. Note: A single call to MUNMAP is assumed to be
- able to unmap memory that may have be allocated using multiple calls
- to MMAP, so long as they are adjacent.
-
-HAVE_MREMAP default: 1 on linux, else 0
- If true realloc() uses mremap() to re-allocate large blocks and
- extend or shrink allocation spaces.
-
-MMAP_CLEARS default: 1 except on WINCE.
- True if mmap clears memory so calloc doesn't need to. This is true
- for standard unix mmap using /dev/zero and on WIN32 except for WINCE.
-
-USE_BUILTIN_FFS default: 0 (i.e., not used)
- Causes malloc to use the builtin ffs() function to compute indices.
- Some compilers may recognize and intrinsify ffs to be faster than the
- supplied C version. Also, the case of x86 using gcc is special-cased
- to an asm instruction, so is already as fast as it can be, and so
- this setting has no effect. Similarly for Win32 under recent MS compilers.
- (On most x86s, the asm version is only slightly faster than the C version.)
-
-malloc_getpagesize default: derive from system includes, or 4096.
- The system page size. To the extent possible, this malloc manages
- memory from the system in page-size units. This may be (and
- usually is) a function rather than a constant. This is ignored
- if WIN32, where page size is determined using getSystemInfo during
- initialization.
-
-USE_DEV_RANDOM default: 0 (i.e., not used)
- Causes malloc to use /dev/random to initialize secure magic seed for
- stamping footers. Otherwise, the current time is used.
-
-NO_MALLINFO default: 0
- If defined, don't compile "mallinfo". This can be a simple way
- of dealing with mismatches between system declarations and
- those in this file.
-
-MALLINFO_FIELD_TYPE default: size_t
- The type of the fields in the mallinfo struct. This was originally
- defined as "int" in SVID etc, but is more usefully defined as
- size_t. The value is used only if HAVE_USR_INCLUDE_MALLOC_H is not set
-
-REALLOC_ZERO_BYTES_FREES default: not defined
- This should be set if a call to realloc with zero bytes should
- be the same as a call to free. Some people think it should. Otherwise,
- since this malloc returns a unique pointer for malloc(0), so does
- realloc(p, 0).
-
-LACKS_UNISTD_H, LACKS_FCNTL_H, LACKS_SYS_PARAM_H, LACKS_SYS_MMAN_H
-LACKS_STRINGS_H, LACKS_STRING_H, LACKS_SYS_TYPES_H, LACKS_ERRNO_H
-LACKS_STDLIB_H default: NOT defined unless on WIN32
- Define these if your system does not have these header files.
- You might need to manually insert some of the declarations they provide.
-
-DEFAULT_GRANULARITY default: page size if MORECORE_CONTIGUOUS,
- system_info.dwAllocationGranularity in WIN32,
- otherwise 64K.
- Also settable using mallopt(M_GRANULARITY, x)
- The unit for allocating and deallocating memory from the system. On
- most systems with contiguous MORECORE, there is no reason to
- make this more than a page. However, systems with MMAP tend to
- either require or encourage larger granularities. You can increase
- this value to prevent system allocation functions to be called so
- often, especially if they are slow. The value must be at least one
- page and must be a power of two. Setting to 0 causes initialization
- to either page size or win32 region size. (Note: In previous
- versions of malloc, the equivalent of this option was called
- "TOP_PAD")
-
-DEFAULT_TRIM_THRESHOLD default: 2MB
- Also settable using mallopt(M_TRIM_THRESHOLD, x)
- The maximum amount of unused top-most memory to keep before
- releasing via malloc_trim in free(). Automatic trimming is mainly
- useful in long-lived programs using contiguous MORECORE. Because
- trimming via sbrk can be slow on some systems, and can sometimes be
- wasteful (in cases where programs immediately afterward allocate
- more large chunks) the value should be high enough so that your
- overall system performance would improve by releasing this much
- memory. As a rough guide, you might set to a value close to the
- average size of a process (program) running on your system.
- Releasing this much memory would allow such a process to run in
- memory. Generally, it is worth tuning trim thresholds when a
- program undergoes phases where several large chunks are allocated
- and released in ways that can reuse each other's storage, perhaps
- mixed with phases where there are no such chunks at all. The trim
- value must be greater than page size to have any useful effect. To
- disable trimming completely, you can set to MAX_SIZE_T. Note that the trick
- some people use of mallocing a huge space and then freeing it at
- program startup, in an attempt to reserve system memory, doesn't
- have the intended effect under automatic trimming, since that memory
- will immediately be returned to the system.
-
-DEFAULT_MMAP_THRESHOLD default: 256K
- Also settable using mallopt(M_MMAP_THRESHOLD, x)
- The request size threshold for using MMAP to directly service a
- request. Requests of at least this size that cannot be allocated
- using already-existing space will be serviced via mmap. (If enough
- normal freed space already exists it is used instead.) Using mmap
- segregates relatively large chunks of memory so that they can be
- individually obtained and released from the host system. A request
- serviced through mmap is never reused by any other request (at least
- not directly; the system may just so happen to remap successive
- requests to the same locations). Segregating space in this way has
- the benefits that: Mmapped space can always be individually released
- back to the system, which helps keep the system level memory demands
- of a long-lived program low. Also, mapped memory doesn't become
- `locked' between other chunks, as can happen with normally allocated
- chunks, which means that even trimming via malloc_trim would not
- release them. However, it has the disadvantage that the space
- cannot be reclaimed, consolidated, and then used to service later
- requests, as happens with normal chunks. The advantages of mmap
- nearly always outweigh disadvantages for "large" chunks, but the
- value of "large" may vary across systems. The default is an
- empirically derived value that works well in most systems. You can
- disable mmap by setting to MAX_SIZE_T.
-
-MAX_RELEASE_CHECK_RATE default: 4095 unless not HAVE_MMAP
- The number of consolidated frees between checks to release
- unused segments when freeing. When using non-contiguous segments,
- especially with multiple mspaces, checking only for topmost space
- doesn't always suffice to trigger trimming. To compensate for this,
- free() will, with a period of MAX_RELEASE_CHECK_RATE (or the
- current number of segments, if greater) try to release unused
- segments to the OS when freeing chunks that result in
- consolidation. The best value for this parameter is a compromise
- between slowing down frees with relatively costly checks that
- rarely trigger versus holding on to unused memory. To effectively
- disable, set to MAX_SIZE_T. This may lead to a very slight speed
- improvement at the expense of carrying around more memory.
-*/
-
-/* Version identifier to allow people to support multiple versions */
-#ifndef DLMALLOC_VERSION
-#define DLMALLOC_VERSION 20804
-#endif /* DLMALLOC_VERSION */
-
-#if defined(linux)
-#define _GNU_SOURCE 1
-#endif
-
-#ifndef WIN32
-#ifdef _WIN32
-#define WIN32 1
-#endif /* _WIN32 */
-#ifdef _WIN32_WCE
-#define LACKS_FCNTL_H
-#define WIN32 1
-#endif /* _WIN32_WCE */
-#endif /* WIN32 */
-#ifdef WIN32
-#define WIN32_LEAN_AND_MEAN
-#ifndef _WIN32_WINNT
-#define _WIN32_WINNT 0x603
-#endif
-#include <windows.h>
-#define HAVE_MMAP 1
-#define HAVE_MORECORE 0
-#define LACKS_UNISTD_H
-#define LACKS_SYS_PARAM_H
-#define LACKS_SYS_MMAN_H
-#define LACKS_STRING_H
-#define LACKS_STRINGS_H
-#define LACKS_SYS_TYPES_H
-#define LACKS_ERRNO_H
-#ifndef MALLOC_FAILURE_ACTION
-#define MALLOC_FAILURE_ACTION
-#endif /* MALLOC_FAILURE_ACTION */
-#ifdef _WIN32_WCE /* WINCE reportedly does not clear */
-#define MMAP_CLEARS 0
-#else
-#define MMAP_CLEARS 1
-#endif /* _WIN32_WCE */
-#endif /* WIN32 */
-
-#if defined(DARWIN) || defined(_DARWIN)
-/* Mac OSX docs advise not to use sbrk; it seems better to use mmap */
-#ifndef HAVE_MORECORE
-#define HAVE_MORECORE 0
-#define HAVE_MMAP 1
-/* OSX allocators provide 16 byte alignment */
-#ifndef MALLOC_ALIGNMENT
-#define MALLOC_ALIGNMENT ((size_t)16U)
-#endif
-#endif /* HAVE_MORECORE */
-#endif /* DARWIN */
-
-#ifndef LACKS_SYS_TYPES_H
-#include <sys/types.h> /* For size_t */
-#endif /* LACKS_SYS_TYPES_H */
-
-/* The maximum possible size_t value has all bits set */
-#define MAX_SIZE_T (~(size_t)0)
-
-#ifndef ONLY_MSPACES
-#define ONLY_MSPACES 0 /* define to a value */
-#else
-#define ONLY_MSPACES 1
-#endif /* ONLY_MSPACES */
-#ifndef MSPACES
-#if ONLY_MSPACES
-#define MSPACES 1
-#else /* ONLY_MSPACES */
-#define MSPACES 0
-#endif /* ONLY_MSPACES */
-#endif /* MSPACES */
-#ifndef MALLOC_ALIGNMENT
-#define MALLOC_ALIGNMENT ((size_t)8U)
-#endif /* MALLOC_ALIGNMENT */
-#ifndef FOOTERS
-#define FOOTERS 0
-#endif /* FOOTERS */
-#ifndef ABORT
-#define ABORT abort()
-#endif /* ABORT */
-#ifndef ABORT_ON_ASSERT_FAILURE
-#define ABORT_ON_ASSERT_FAILURE 1
-#endif /* ABORT_ON_ASSERT_FAILURE */
-#ifndef PROCEED_ON_ERROR
-#define PROCEED_ON_ERROR 0
-#endif /* PROCEED_ON_ERROR */
-#ifndef USE_LOCKS
-#define USE_LOCKS 0
-#endif /* USE_LOCKS */
-#ifndef USE_SPIN_LOCKS
-#if USE_LOCKS && (defined(__GNUC__) && ((defined(__i386__) || defined(__x86_64__)))) || (defined(_MSC_VER) && _MSC_VER>=1310)
-#define USE_SPIN_LOCKS 1
-#else
-#define USE_SPIN_LOCKS 0
-#endif /* USE_LOCKS && ... */
-#endif /* USE_SPIN_LOCKS */
-#ifndef INSECURE
-#define INSECURE 0
-#endif /* INSECURE */
-#ifndef HAVE_MMAP
-#define HAVE_MMAP 1
-#endif /* HAVE_MMAP */
-#ifndef MMAP_CLEARS
-#define MMAP_CLEARS 1
-#endif /* MMAP_CLEARS */
-#ifndef HAVE_MREMAP
-#ifdef linux
-#define HAVE_MREMAP 1
-#else /* linux */
-#define HAVE_MREMAP 0
-#endif /* linux */
-#endif /* HAVE_MREMAP */
-#ifndef MALLOC_FAILURE_ACTION
-#define MALLOC_FAILURE_ACTION errno = ENOMEM;
-#endif /* MALLOC_FAILURE_ACTION */
-#ifndef HAVE_MORECORE
-#if ONLY_MSPACES
-#define HAVE_MORECORE 0
-#else /* ONLY_MSPACES */
-#define HAVE_MORECORE 1
-#endif /* ONLY_MSPACES */
-#endif /* HAVE_MORECORE */
-#if !HAVE_MORECORE
-#define MORECORE_CONTIGUOUS 0
-#else /* !HAVE_MORECORE */
-#define MORECORE_DEFAULT sbrk
-#ifndef MORECORE_CONTIGUOUS
-#define MORECORE_CONTIGUOUS 1
-#endif /* MORECORE_CONTIGUOUS */
-#endif /* HAVE_MORECORE */
-#ifndef DEFAULT_GRANULARITY
-#if (MORECORE_CONTIGUOUS || defined(WIN32))
-#define DEFAULT_GRANULARITY (0) /* 0 means to compute in init_mparams */
-#else /* MORECORE_CONTIGUOUS */
-#define DEFAULT_GRANULARITY ((size_t)64U * (size_t)1024U)
-#endif /* MORECORE_CONTIGUOUS */
-#endif /* DEFAULT_GRANULARITY */
-#ifndef DEFAULT_TRIM_THRESHOLD
-#ifndef MORECORE_CANNOT_TRIM
-#define DEFAULT_TRIM_THRESHOLD ((size_t)2U * (size_t)1024U * (size_t)1024U)
-#else /* MORECORE_CANNOT_TRIM */
-#define DEFAULT_TRIM_THRESHOLD MAX_SIZE_T
-#endif /* MORECORE_CANNOT_TRIM */
-#endif /* DEFAULT_TRIM_THRESHOLD */
-#ifndef DEFAULT_MMAP_THRESHOLD
-#if HAVE_MMAP
-#define DEFAULT_MMAP_THRESHOLD ((size_t)256U * (size_t)1024U)
-#else /* HAVE_MMAP */
-#define DEFAULT_MMAP_THRESHOLD MAX_SIZE_T
-#endif /* HAVE_MMAP */
-#endif /* DEFAULT_MMAP_THRESHOLD */
-#ifndef MAX_RELEASE_CHECK_RATE
-#if HAVE_MMAP
-#define MAX_RELEASE_CHECK_RATE 4095
-#else
-#define MAX_RELEASE_CHECK_RATE MAX_SIZE_T
-#endif /* HAVE_MMAP */
-#endif /* MAX_RELEASE_CHECK_RATE */
-#ifndef USE_BUILTIN_FFS
-#define USE_BUILTIN_FFS 0
-#endif /* USE_BUILTIN_FFS */
-#ifndef USE_DEV_RANDOM
-#define USE_DEV_RANDOM 0
-#endif /* USE_DEV_RANDOM */
-#ifndef NO_MALLINFO
-#define NO_MALLINFO 0
-#endif /* NO_MALLINFO */
-#ifndef MALLINFO_FIELD_TYPE
-#define MALLINFO_FIELD_TYPE size_t
-#endif /* MALLINFO_FIELD_TYPE */
-#ifndef NO_SEGMENT_TRAVERSAL
-#define NO_SEGMENT_TRAVERSAL 0
-#endif /* NO_SEGMENT_TRAVERSAL */
-
-/*
- mallopt tuning options. SVID/XPG defines four standard parameter
- numbers for mallopt, normally defined in malloc.h. None of these
- are used in this malloc, so setting them has no effect. But this
- malloc does support the following options.
-*/
-
-#define M_TRIM_THRESHOLD (-1)
-#define M_GRANULARITY (-2)
-#define M_MMAP_THRESHOLD (-3)
-
-/* ------------------------ Mallinfo declarations ------------------------ */
-
-#if !NO_MALLINFO
-/*
- This version of malloc supports the standard SVID/XPG mallinfo
- routine that returns a struct containing usage properties and
- statistics. It should work on any system that has a
- /usr/include/malloc.h defining struct mallinfo. The main
- declaration needed is the mallinfo struct that is returned (by-copy)
- by mallinfo(). The malloinfo struct contains a bunch of fields that
- are not even meaningful in this version of malloc. These fields are
- are instead filled by mallinfo() with other numbers that might be of
- interest.
-
- HAVE_USR_INCLUDE_MALLOC_H should be set if you have a
- /usr/include/malloc.h file that includes a declaration of struct
- mallinfo. If so, it is included; else a compliant version is
- declared below. These must be precisely the same for mallinfo() to
- work. The original SVID version of this struct, defined on most
- systems with mallinfo, declares all fields as ints. But some others
- define as unsigned long. If your system defines the fields using a
- type of different width than listed here, you MUST #include your
- system version and #define HAVE_USR_INCLUDE_MALLOC_H.
-*/
-
-/* #define HAVE_USR_INCLUDE_MALLOC_H */
-
-#ifdef HAVE_USR_INCLUDE_MALLOC_H
-#include "/usr/include/malloc.h"
-#else /* HAVE_USR_INCLUDE_MALLOC_H */
-#ifndef STRUCT_MALLINFO_DECLARED
-#define STRUCT_MALLINFO_DECLARED 1
-struct mallinfo {
- MALLINFO_FIELD_TYPE arena; /* non-mmapped space allocated from system */
- MALLINFO_FIELD_TYPE ordblks; /* number of free chunks */
- MALLINFO_FIELD_TYPE smblks; /* always 0 */
- MALLINFO_FIELD_TYPE hblks; /* always 0 */
- MALLINFO_FIELD_TYPE hblkhd; /* space in mmapped regions */
- MALLINFO_FIELD_TYPE usmblks; /* maximum total allocated space */
- MALLINFO_FIELD_TYPE fsmblks; /* always 0 */
- MALLINFO_FIELD_TYPE uordblks; /* total allocated space */
- MALLINFO_FIELD_TYPE fordblks; /* total free space */
- MALLINFO_FIELD_TYPE keepcost; /* releasable (via malloc_trim) space */
-};
-#endif /* STRUCT_MALLINFO_DECLARED */
-#endif /* HAVE_USR_INCLUDE_MALLOC_H */
-#endif /* NO_MALLINFO */
-
-/*
- Try to persuade compilers to inline. The most critical functions for
- inlining are defined as macros, so these aren't used for them.
-*/
-
-#ifdef __MINGW64_VERSION_MAJOR
-#undef FORCEINLINE
-#endif
-#ifndef FORCEINLINE
- #if defined(__GNUC__)
-#define FORCEINLINE __inline __attribute__ ((always_inline))
- #elif defined(_MSC_VER)
- #define FORCEINLINE __forceinline
- #endif
-#endif
-#ifndef NOINLINE
- #if defined(__GNUC__)
- #define NOINLINE __attribute__ ((noinline))
- #elif defined(_MSC_VER)
- #define NOINLINE __declspec(noinline)
- #else
- #define NOINLINE
- #endif
-#endif
-
-#ifdef __cplusplus
-extern "C" {
-#ifndef FORCEINLINE
- #define FORCEINLINE inline
-#endif
-#endif /* __cplusplus */
-#ifndef FORCEINLINE
- #define FORCEINLINE
-#endif
-
-#if !ONLY_MSPACES
-
-/* ------------------- Declarations of public routines ------------------- */
-
-#ifndef USE_DL_PREFIX
-#define dlcalloc calloc
-#define dlfree free
-#define dlmalloc malloc
-#define dlmemalign memalign
-#define dlrealloc realloc
-#define dlvalloc valloc
-#define dlpvalloc pvalloc
-#define dlmallinfo mallinfo
-#define dlmallopt mallopt
-#define dlmalloc_trim malloc_trim
-#define dlmalloc_stats malloc_stats
-#define dlmalloc_usable_size malloc_usable_size
-#define dlmalloc_footprint malloc_footprint
-#define dlmalloc_max_footprint malloc_max_footprint
-#define dlindependent_calloc independent_calloc
-#define dlindependent_comalloc independent_comalloc
-#endif /* USE_DL_PREFIX */
-
-
-/*
- malloc(size_t n)
- Returns a pointer to a newly allocated chunk of at least n bytes, or
- null if no space is available, in which case errno is set to ENOMEM
- on ANSI C systems.
-
- If n is zero, malloc returns a minimum-sized chunk. (The minimum
- size is 16 bytes on most 32bit systems, and 32 bytes on 64bit
- systems.) Note that size_t is an unsigned type, so calls with
- arguments that would be negative if signed are interpreted as
- requests for huge amounts of space, which will often fail. The
- maximum supported value of n differs across systems, but is in all
- cases less than the maximum representable value of a size_t.
-*/
-void* dlmalloc(size_t);
-
-/*
- free(void* p)
- Releases the chunk of memory pointed to by p, that had been previously
- allocated using malloc or a related routine such as realloc.
- It has no effect if p is null. If p was not malloced or already
- freed, free(p) will by default cause the current program to abort.
-*/
-void dlfree(void*);
-
-/*
- calloc(size_t n_elements, size_t element_size);
- Returns a pointer to n_elements * element_size bytes, with all locations
- set to zero.
-*/
-void* dlcalloc(size_t, size_t);
-
-/*
- realloc(void* p, size_t n)
- Returns a pointer to a chunk of size n that contains the same data
- as does chunk p up to the minimum of (n, p's size) bytes, or null
- if no space is available.
-
- The returned pointer may or may not be the same as p. The algorithm
- prefers extending p in most cases when possible, otherwise it
- employs the equivalent of a malloc-copy-free sequence.
-
- If p is null, realloc is equivalent to malloc.
-
- If space is not available, realloc returns null, errno is set (if on
- ANSI) and p is NOT freed.
-
- if n is for fewer bytes than already held by p, the newly unused
- space is lopped off and freed if possible. realloc with a size
- argument of zero (re)allocates a minimum-sized chunk.
-
- The old unix realloc convention of allowing the last-free'd chunk
- to be used as an argument to realloc is not supported.
-*/
-
-void* dlrealloc(void*, size_t);
-
-/*
- memalign(size_t alignment, size_t n);
- Returns a pointer to a newly allocated chunk of n bytes, aligned
- in accord with the alignment argument.
-
- The alignment argument should be a power of two. If the argument is
- not a power of two, the nearest greater power is used.
- 8-byte alignment is guaranteed by normal malloc calls, so don't
- bother calling memalign with an argument of 8 or less.
-
- Overreliance on memalign is a sure way to fragment space.
-*/
-void* dlmemalign(size_t, size_t);
-
-/*
- valloc(size_t n);
- Equivalent to memalign(pagesize, n), where pagesize is the page
- size of the system. If the pagesize is unknown, 4096 is used.
-*/
-void* dlvalloc(size_t);
-
-/*
- mallopt(int parameter_number, int parameter_value)
- Sets tunable parameters The format is to provide a
- (parameter-number, parameter-value) pair. mallopt then sets the
- corresponding parameter to the argument value if it can (i.e., so
- long as the value is meaningful), and returns 1 if successful else
- 0. To workaround the fact that mallopt is specified to use int,
- not size_t parameters, the value -1 is specially treated as the
- maximum unsigned size_t value.
-
- SVID/XPG/ANSI defines four standard param numbers for mallopt,
- normally defined in malloc.h. None of these are use in this malloc,
- so setting them has no effect. But this malloc also supports other
- options in mallopt. See below for details. Briefly, supported
- parameters are as follows (listed defaults are for "typical"
- configurations).
-
- Symbol param # default allowed param values
- M_TRIM_THRESHOLD -1 2*1024*1024 any (-1 disables)
- M_GRANULARITY -2 page size any power of 2 >= page size
- M_MMAP_THRESHOLD -3 256*1024 any (or 0 if no MMAP support)
-*/
-int dlmallopt(int, int);
-
-/*
- malloc_footprint();
- Returns the number of bytes obtained from the system. The total
- number of bytes allocated by malloc, realloc etc., is less than this
- value. Unlike mallinfo, this function returns only a precomputed
- result, so can be called frequently to monitor memory consumption.
- Even if locks are otherwise defined, this function does not use them,
- so results might not be up to date.
-*/
-size_t dlmalloc_footprint(void);
-
-/*
- malloc_max_footprint();
- Returns the maximum number of bytes obtained from the system. This
- value will be greater than current footprint if deallocated space
- has been reclaimed by the system. The peak number of bytes allocated
- by malloc, realloc etc., is less than this value. Unlike mallinfo,
- this function returns only a precomputed result, so can be called
- frequently to monitor memory consumption. Even if locks are
- otherwise defined, this function does not use them, so results might
- not be up to date.
-*/
-size_t dlmalloc_max_footprint(void);
-
-#if !NO_MALLINFO
-/*
- mallinfo()
- Returns (by copy) a struct containing various summary statistics:
-
- arena: current total non-mmapped bytes allocated from system
- ordblks: the number of free chunks
- smblks: always zero.
- hblks: current number of mmapped regions
- hblkhd: total bytes held in mmapped regions
- usmblks: the maximum total allocated space. This will be greater
- than current total if trimming has occurred.
- fsmblks: always zero
- uordblks: current total allocated space (normal or mmapped)
- fordblks: total free space
- keepcost: the maximum number of bytes that could ideally be released
- back to system via malloc_trim. ("ideally" means that
- it ignores page restrictions etc.)
-
- Because these fields are ints, but internal bookkeeping may
- be kept as longs, the reported values may wrap around zero and
- thus be inaccurate.
-*/
-struct mallinfo dlmallinfo(void);
-#endif /* NO_MALLINFO */
-
-/*
- independent_calloc(size_t n_elements, size_t element_size, void* chunks[]);
-
- independent_calloc is similar to calloc, but instead of returning a
- single cleared space, it returns an array of pointers to n_elements
- independent elements that can hold contents of size elem_size, each
- of which starts out cleared, and can be independently freed,
- realloc'ed etc. The elements are guaranteed to be adjacently
- allocated (this is not guaranteed to occur with multiple callocs or
- mallocs), which may also improve cache locality in some
- applications.
-
- The "chunks" argument is optional (i.e., may be null, which is
- probably the most typical usage). If it is null, the returned array
- is itself dynamically allocated and should also be freed when it is
- no longer needed. Otherwise, the chunks array must be of at least
- n_elements in length. It is filled in with the pointers to the
- chunks.
-
- In either case, independent_calloc returns this pointer array, or
- null if the allocation failed. If n_elements is zero and "chunks"
- is null, it returns a chunk representing an array with zero elements
- (which should be freed if not wanted).
-
- Each element must be individually freed when it is no longer
- needed. If you'd like to instead be able to free all at once, you
- should instead use regular calloc and assign pointers into this
- space to represent elements. (In this case though, you cannot
- independently free elements.)
-
- independent_calloc simplifies and speeds up implementations of many
- kinds of pools. It may also be useful when constructing large data
- structures that initially have a fixed number of fixed-sized nodes,
- but the number is not known at compile time, and some of the nodes
- may later need to be freed. For example:
-
- struct Node { int item; struct Node* next; };
-
- struct Node* build_list() {
- struct Node** pool;
- int n = read_number_of_nodes_needed();
- if (n <= 0) return 0;
- pool = (struct Node**)(independent_calloc(n, sizeof(struct Node), 0);
- if (pool == 0) die();
- // organize into a linked list...
- struct Node* first = pool[0];
- for (i = 0; i < n-1; ++i)
- pool[i]->next = pool[i+1];
- free(pool); // Can now free the array (or not, if it is needed later)
- return first;
- }
-*/
-void** dlindependent_calloc(size_t, size_t, void**);
-
-/*
- independent_comalloc(size_t n_elements, size_t sizes[], void* chunks[]);
-
- independent_comalloc allocates, all at once, a set of n_elements
- chunks with sizes indicated in the "sizes" array. It returns
- an array of pointers to these elements, each of which can be
- independently freed, realloc'ed etc. The elements are guaranteed to
- be adjacently allocated (this is not guaranteed to occur with
- multiple callocs or mallocs), which may also improve cache locality
- in some applications.
-
- The "chunks" argument is optional (i.e., may be null). If it is null
- the returned array is itself dynamically allocated and should also
- be freed when it is no longer needed. Otherwise, the chunks array
- must be of at least n_elements in length. It is filled in with the
- pointers to the chunks.
-
- In either case, independent_comalloc returns this pointer array, or
- null if the allocation failed. If n_elements is zero and chunks is
- null, it returns a chunk representing an array with zero elements
- (which should be freed if not wanted).
-
- Each element must be individually freed when it is no longer
- needed. If you'd like to instead be able to free all at once, you
- should instead use a single regular malloc, and assign pointers at
- particular offsets in the aggregate space. (In this case though, you
- cannot independently free elements.)
-
- independent_comallac differs from independent_calloc in that each
- element may have a different size, and also that it does not
- automatically clear elements.
-
- independent_comalloc can be used to speed up allocation in cases
- where several structs or objects must always be allocated at the
- same time. For example:
-
- struct Head { ... }
- struct Foot { ... }
-
- void send_message(char* msg) {
- int msglen = strlen(msg);
- size_t sizes[3] = { sizeof(struct Head), msglen, sizeof(struct Foot) };
- void* chunks[3];
- if (independent_comalloc(3, sizes, chunks) == 0)
- die();
- struct Head* head = (struct Head*)(chunks[0]);
- char* body = (char*)(chunks[1]);
- struct Foot* foot = (struct Foot*)(chunks[2]);
- // ...
- }
-
- In general though, independent_comalloc is worth using only for
- larger values of n_elements. For small values, you probably won't
- detect enough difference from series of malloc calls to bother.
-
- Overuse of independent_comalloc can increase overall memory usage,
- since it cannot reuse existing noncontiguous small chunks that
- might be available for some of the elements.
-*/
-void** dlindependent_comalloc(size_t, size_t*, void**);
-
-
-/*
- pvalloc(size_t n);
- Equivalent to valloc(minimum-page-that-holds(n)), that is,
- round up n to nearest pagesize.
- */
-void* dlpvalloc(size_t);
-
-/*
- malloc_trim(size_t pad);
-
- If possible, gives memory back to the system (via negative arguments
- to sbrk) if there is unused memory at the `high' end of the malloc
- pool or in unused MMAP segments. You can call this after freeing
- large blocks of memory to potentially reduce the system-level memory
- requirements of a program. However, it cannot guarantee to reduce
- memory. Under some allocation patterns, some large free blocks of
- memory will be locked between two used chunks, so they cannot be
- given back to the system.
-
- The `pad' argument to malloc_trim represents the amount of free
- trailing space to leave untrimmed. If this argument is zero, only
- the minimum amount of memory to maintain internal data structures
- will be left. Non-zero arguments can be supplied to maintain enough
- trailing space to service future expected allocations without having
- to re-obtain memory from the system.
-
- Malloc_trim returns 1 if it actually released any memory, else 0.
-*/
-int dlmalloc_trim(size_t);
-
-/*
- malloc_stats();
- Prints on stderr the amount of space obtained from the system (both
- via sbrk and mmap), the maximum amount (which may be more than
- current if malloc_trim and/or munmap got called), and the current
- number of bytes allocated via malloc (or realloc, etc) but not yet
- freed. Note that this is the number of bytes allocated, not the
- number requested. It will be larger than the number requested
- because of alignment and bookkeeping overhead. Because it includes
- alignment wastage as being in use, this figure may be greater than
- zero even when no user-level chunks are allocated.
-
- The reported current and maximum system memory can be inaccurate if
- a program makes other calls to system memory allocation functions
- (normally sbrk) outside of malloc.
-
- malloc_stats prints only the most commonly interesting statistics.
- More information can be obtained by calling mallinfo.
-*/
-void dlmalloc_stats(void);
-
-#endif /* ONLY_MSPACES */
-
-/*
- malloc_usable_size(void* p);
-
- Returns the number of bytes you can actually use in
- an allocated chunk, which may be more than you requested (although
- often not) due to alignment and minimum size constraints.
- You can use this many bytes without worrying about
- overwriting other allocated objects. This is not a particularly great
- programming practice. malloc_usable_size can be more useful in
- debugging and assertions, for example:
-
- p = malloc(n);
- assert(malloc_usable_size(p) >= 256);
-*/
-size_t dlmalloc_usable_size(void*);
-
-
-#if MSPACES
-
-/*
- mspace is an opaque type representing an independent
- region of space that supports mspace_malloc, etc.
-*/
-typedef void* mspace;
-
-/*
- create_mspace creates and returns a new independent space with the
- given initial capacity, or, if 0, the default granularity size. It
- returns null if there is no system memory available to create the
- space. If argument locked is non-zero, the space uses a separate
- lock to control access. The capacity of the space will grow
- dynamically as needed to service mspace_malloc requests. You can
- control the sizes of incremental increases of this space by
- compiling with a different DEFAULT_GRANULARITY or dynamically
- setting with mallopt(M_GRANULARITY, value).
-*/
-mspace create_mspace(size_t capacity, int locked);
-
-/*
- destroy_mspace destroys the given space, and attempts to return all
- of its memory back to the system, returning the total number of
- bytes freed. After destruction, the results of access to all memory
- used by the space become undefined.
-*/
-size_t destroy_mspace(mspace msp);
-
-/*
- create_mspace_with_base uses the memory supplied as the initial base
- of a new mspace. Part (less than 128*sizeof(size_t) bytes) of this
- space is used for bookkeeping, so the capacity must be at least this
- large. (Otherwise 0 is returned.) When this initial space is
- exhausted, additional memory will be obtained from the system.
- Destroying this space will deallocate all additionally allocated
- space (if possible) but not the initial base.
-*/
-mspace create_mspace_with_base(void* base, size_t capacity, int locked);
-
-/*
- mspace_mmap_large_chunks controls whether requests for large chunks
- are allocated in their own mmapped regions, separate from others in
- this mspace. By default this is enabled, which reduces
- fragmentation. However, such chunks are not necessarily released to
- the system upon destroy_mspace. Disabling by setting to false may
- increase fragmentation, but avoids leakage when relying on
- destroy_mspace to release all memory allocated using this space.
-*/
-int mspace_mmap_large_chunks(mspace msp, int enable);
-
-
-/*
- mspace_malloc behaves as malloc, but operates within
- the given space.
-*/
-void* mspace_malloc(mspace msp, size_t bytes);
-
-/*
- mspace_free behaves as free, but operates within
- the given space.
-
- If compiled with FOOTERS==1, mspace_free is not actually needed.
- free may be called instead of mspace_free because freed chunks from
- any space are handled by their originating spaces.
-*/
-void mspace_free(mspace msp, void* mem);
-
-/*
- mspace_realloc behaves as realloc, but operates within
- the given space.
-
- If compiled with FOOTERS==1, mspace_realloc is not actually
- needed. realloc may be called instead of mspace_realloc because
- realloced chunks from any space are handled by their originating
- spaces.
-*/
-void* mspace_realloc(mspace msp, void* mem, size_t newsize);
-
-/*
- mspace_calloc behaves as calloc, but operates within
- the given space.
-*/
-void* mspace_calloc(mspace msp, size_t n_elements, size_t elem_size);
-
-/*
- mspace_memalign behaves as memalign, but operates within
- the given space.
-*/
-void* mspace_memalign(mspace msp, size_t alignment, size_t bytes);
-
-/*
- mspace_independent_calloc behaves as independent_calloc, but
- operates within the given space.
-*/
-void** mspace_independent_calloc(mspace msp, size_t n_elements,
- size_t elem_size, void* chunks[]);
-
-/*
- mspace_independent_comalloc behaves as independent_comalloc, but
- operates within the given space.
-*/
-void** mspace_independent_comalloc(mspace msp, size_t n_elements,
- size_t sizes[], void* chunks[]);
-
-/*
- mspace_footprint() returns the number of bytes obtained from the
- system for this space.
-*/
-size_t mspace_footprint(mspace msp);
-
-/*
- mspace_max_footprint() returns the peak number of bytes obtained from the
- system for this space.
-*/
-size_t mspace_max_footprint(mspace msp);
-
-
-#if !NO_MALLINFO
-/*
- mspace_mallinfo behaves as mallinfo, but reports properties of
- the given space.
-*/
-struct mallinfo mspace_mallinfo(mspace msp);
-#endif /* NO_MALLINFO */
-
-/*
- malloc_usable_size(void* p) behaves the same as malloc_usable_size;
-*/
- size_t mspace_usable_size(void* mem);
-
-/*
- mspace_malloc_stats behaves as malloc_stats, but reports
- properties of the given space.
-*/
-void mspace_malloc_stats(mspace msp);
-
-/*
- mspace_trim behaves as malloc_trim, but
- operates within the given space.
-*/
-int mspace_trim(mspace msp, size_t pad);
-
-/*
- An alias for mallopt.
-*/
-int mspace_mallopt(int, int);
-
-#endif /* MSPACES */
-
-#ifdef __cplusplus
-}; /* end of extern "C" */
-#endif /* __cplusplus */
-
-/*
- ========================================================================
- To make a fully customizable malloc.h header file, cut everything
- above this line, put into file malloc.h, edit to suit, and #include it
- on the next line, as well as in programs that use this malloc.
- ========================================================================
-*/
-
-/* #include "malloc.h" */
-
-/*------------------------------ internal #includes ---------------------- */
-
-#ifdef WIN32
-#ifndef __GNUC__
-#pragma warning( disable : 4146 ) /* no "unsigned" warnings */
-#endif
-#endif /* WIN32 */
-
-#include <stdio.h> /* for printing in malloc_stats */
-
-#ifndef LACKS_ERRNO_H
-#include <errno.h> /* for MALLOC_FAILURE_ACTION */
-#endif /* LACKS_ERRNO_H */
-#if FOOTERS
-#include <time.h> /* for magic initialization */
-#endif /* FOOTERS */
-#ifndef LACKS_STDLIB_H
-#include <stdlib.h> /* for abort() */
-#endif /* LACKS_STDLIB_H */
-#ifdef DEBUG
-#if ABORT_ON_ASSERT_FAILURE
-#define assert(x) if(!(x)) ABORT
-#else /* ABORT_ON_ASSERT_FAILURE */
-#include <assert.h>
-#endif /* ABORT_ON_ASSERT_FAILURE */
-#else /* DEBUG */
-#ifndef assert
-#define assert(x)
-#endif
-#define DEBUG 0
-#endif /* DEBUG */
-#ifndef LACKS_STRING_H
-#include <string.h> /* for memset etc */
-#endif /* LACKS_STRING_H */
-#if USE_BUILTIN_FFS
-#ifndef LACKS_STRINGS_H
-#include <strings.h> /* for ffs */
-#endif /* LACKS_STRINGS_H */
-#endif /* USE_BUILTIN_FFS */
-#if HAVE_MMAP
-#ifndef LACKS_SYS_MMAN_H
-#include <sys/mman.h> /* for mmap */
-#endif /* LACKS_SYS_MMAN_H */
-#ifndef LACKS_FCNTL_H
-#include <fcntl.h>
-#endif /* LACKS_FCNTL_H */
-#endif /* HAVE_MMAP */
-#ifndef LACKS_UNISTD_H
-#include <unistd.h> /* for sbrk, sysconf */
-#else /* LACKS_UNISTD_H */
-#if !defined(__FreeBSD__) && !defined(__OpenBSD__) && !defined(__NetBSD__)
-extern void* sbrk(ptrdiff_t);
-#endif /* FreeBSD etc */
-#endif /* LACKS_UNISTD_H */
-
-/* Declarations for locking */
-#if USE_LOCKS
-#ifndef WIN32
-#include <pthread.h>
-#if defined (__SVR4) && defined (__sun) /* solaris */
-#include <thread.h>
-#endif /* solaris */
-#else
-#ifndef _M_AMD64
-/* These are already defined on AMD64 builds */
-#ifdef __cplusplus
-extern "C" {
-#endif /* __cplusplus */
-#ifndef __MINGW32__
-LONG __cdecl _InterlockedCompareExchange(LONG volatile *Dest, LONG Exchange, LONG Comp);
-LONG __cdecl _InterlockedExchange(LONG volatile *Target, LONG Value);
-#endif
-#ifdef __cplusplus
-}
-#endif /* __cplusplus */
-#endif /* _M_AMD64 */
-#ifndef __MINGW32__
-#pragma intrinsic (_InterlockedCompareExchange)
-#pragma intrinsic (_InterlockedExchange)
-#else
- /* --[ start GCC compatibility ]----------------------------------------------
- * Compatibility <intrin_x86.h> header for GCC -- GCC equivalents of intrinsic
- * Microsoft Visual C++ functions. Originally developed for the ReactOS
- * (<http://www.reactos.org/>) and TinyKrnl (<http://www.tinykrnl.org/>)
- * projects.
- *
- * Copyright (c) 2006 KJK::Hyperion <hackbunny@reactos.com>
- *
- * Permission is hereby granted, free of charge, to any person obtaining a
- * copy of this software and associated documentation files (the "Software"),
- * to deal in the Software without restriction, including without limitation
- * the rights to use, copy, modify, merge, publish, distribute, sublicense,
- * and/or sell copies of the Software, and to permit persons to whom the
- * Software is furnished to do so, subject to the following conditions:
- *
- * The above copyright notice and this permission notice shall be included in
- * all copies or substantial portions of the Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
- * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
- * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
- * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
- * DEALINGS IN THE SOFTWARE.
- */
-
- /*** Atomic operations ***/
- #if (__GNUC__ * 10000 + __GNUC_MINOR__ * 100 + __GNUC_PATCHLEVEL__) > 40100
- #undef _ReadWriteBarrier
- #define _ReadWriteBarrier() __sync_synchronize()
- #else
- static __inline__ __attribute__((always_inline)) long __sync_lock_test_and_set(volatile long * const Target, const long Value)
- {
- long res;
- __asm__ __volatile__("xchg%z0 %2, %0" : "=g" (*(Target)), "=r" (res) : "1" (Value));
- return res;
- }
- static void __inline__ __attribute__((always_inline)) _MemoryBarrier(void)
- {
- __asm__ __volatile__("" : : : "memory");
- }
- #define _ReadWriteBarrier() _MemoryBarrier()
- #endif
- /* BUGBUG: GCC only supports full barriers */
- static __inline__ __attribute__((always_inline)) long _InterlockedExchange(volatile long * const Target, const long Value)
- {
- /* NOTE: __sync_lock_test_and_set would be an acquire barrier, so we force a full barrier */
- _ReadWriteBarrier();
- return __sync_lock_test_and_set(Target, Value);
- }
- /* --[ end GCC compatibility ]---------------------------------------------- */
-#endif
-#define interlockedcompareexchange _InterlockedCompareExchange
-#define interlockedexchange _InterlockedExchange
-#endif /* Win32 */
-#endif /* USE_LOCKS */
-
-/* Declarations for bit scanning on win32 */
-#if defined(_MSC_VER) && _MSC_VER>=1300
-#ifndef BitScanForward /* Try to avoid pulling in WinNT.h */
-#ifdef __cplusplus
-extern "C" {
-#endif /* __cplusplus */
-unsigned char _BitScanForward(unsigned long *index, unsigned long mask);
-unsigned char _BitScanReverse(unsigned long *index, unsigned long mask);
-#ifdef __cplusplus
-}
-#endif /* __cplusplus */
-
-#define BitScanForward _BitScanForward
-#define BitScanReverse _BitScanReverse
-#pragma intrinsic(_BitScanForward)
-#pragma intrinsic(_BitScanReverse)
-#endif /* BitScanForward */
-#endif /* defined(_MSC_VER) && _MSC_VER>=1300 */
-
-#ifndef WIN32
-#ifndef malloc_getpagesize
-# ifdef _SC_PAGESIZE /* some SVR4 systems omit an underscore */
-# ifndef _SC_PAGE_SIZE
-# define _SC_PAGE_SIZE _SC_PAGESIZE
-# endif
-# endif
-# ifdef _SC_PAGE_SIZE
-# define malloc_getpagesize sysconf(_SC_PAGE_SIZE)
-# else
-# if defined(BSD) || defined(DGUX) || defined(HAVE_GETPAGESIZE)
- extern size_t getpagesize();
-# define malloc_getpagesize getpagesize()
-# else
-# ifdef WIN32 /* use supplied emulation of getpagesize */
-# define malloc_getpagesize getpagesize()
-# else
-# ifndef LACKS_SYS_PARAM_H
-# include <sys/param.h>
-# endif
-# ifdef EXEC_PAGESIZE
-# define malloc_getpagesize EXEC_PAGESIZE
-# else
-# ifdef NBPG
-# ifndef CLSIZE
-# define malloc_getpagesize NBPG
-# else
-# define malloc_getpagesize (NBPG * CLSIZE)
-# endif
-# else
-# ifdef NBPC
-# define malloc_getpagesize NBPC
-# else
-# ifdef PAGESIZE
-# define malloc_getpagesize PAGESIZE
-# else /* just guess */
-# define malloc_getpagesize ((size_t)4096U)
-# endif
-# endif
-# endif
-# endif
-# endif
-# endif
-# endif
-#endif
-#endif
-
-
-
-/* ------------------- size_t and alignment properties -------------------- */
-
-/* The byte and bit size of a size_t */
-#define SIZE_T_SIZE (sizeof(size_t))
-#define SIZE_T_BITSIZE (sizeof(size_t) << 3)
-
-/* Some constants coerced to size_t */
-/* Annoying but necessary to avoid errors on some platforms */
-#define SIZE_T_ZERO ((size_t)0)
-#define SIZE_T_ONE ((size_t)1)
-#define SIZE_T_TWO ((size_t)2)
-#define SIZE_T_FOUR ((size_t)4)
-#define TWO_SIZE_T_SIZES (SIZE_T_SIZE<<1)
-#define FOUR_SIZE_T_SIZES (SIZE_T_SIZE<<2)
-#define SIX_SIZE_T_SIZES (FOUR_SIZE_T_SIZES+TWO_SIZE_T_SIZES)
-#define HALF_MAX_SIZE_T (MAX_SIZE_T / 2U)
-
-/* The bit mask value corresponding to MALLOC_ALIGNMENT */
-#define CHUNK_ALIGN_MASK (MALLOC_ALIGNMENT - SIZE_T_ONE)
-
-/* True if address a has acceptable alignment */
-#define is_aligned(A) (((size_t)((A)) & (CHUNK_ALIGN_MASK)) == 0)
-
-/* the number of bytes to offset an address to align it */
-#define align_offset(A)\
- ((((size_t)(A) & CHUNK_ALIGN_MASK) == 0)? 0 :\
- ((MALLOC_ALIGNMENT - ((size_t)(A) & CHUNK_ALIGN_MASK)) & CHUNK_ALIGN_MASK))
-
-/* -------------------------- MMAP preliminaries ------------------------- */
-
-/*
- If HAVE_MORECORE or HAVE_MMAP are false, we just define calls and
- checks to fail so compiler optimizer can delete code rather than
- using so many "#if"s.
-*/
-
-
-/* MORECORE and MMAP must return MFAIL on failure */
-#define MFAIL ((void*)(MAX_SIZE_T))
-#define CMFAIL ((char*)(MFAIL)) /* defined for convenience */
-
-#if HAVE_MMAP
-
-#ifndef WIN32
-#define MUNMAP_DEFAULT(a, s) munmap((a), (s))
-#define MMAP_PROT (PROT_READ|PROT_WRITE)
-#if !defined(MAP_ANONYMOUS) && defined(MAP_ANON)
-#define MAP_ANONYMOUS MAP_ANON
-#endif /* MAP_ANON */
-#ifdef MAP_ANONYMOUS
-#define MMAP_FLAGS (MAP_PRIVATE|MAP_ANONYMOUS)
-#define MMAP_DEFAULT(s) mmap(0, (s), MMAP_PROT, MMAP_FLAGS, -1, 0)
-#else /* MAP_ANONYMOUS */
-/*
- Nearly all versions of mmap support MAP_ANONYMOUS, so the following
- is unlikely to be needed, but is supplied just in case.
-*/
-#define MMAP_FLAGS (MAP_PRIVATE)
-static int dev_zero_fd = -1; /* Cached file descriptor for /dev/zero. */
-#define MMAP_DEFAULT(s) ((dev_zero_fd < 0) ? \
- (dev_zero_fd = open("/dev/zero", O_RDWR), \
- mmap(0, (s), MMAP_PROT, MMAP_FLAGS, dev_zero_fd, 0)) : \
- mmap(0, (s), MMAP_PROT, MMAP_FLAGS, dev_zero_fd, 0))
-#endif /* MAP_ANONYMOUS */
-
-#define DIRECT_MMAP_DEFAULT(s) MMAP_DEFAULT(s)
-
-#else /* WIN32 */
-
-/* Win32 MMAP via VirtualAlloc */
-static FORCEINLINE void* win32mmap(size_t size) {
- void* ptr = VirtualAlloc(0, size, MEM_RESERVE|MEM_COMMIT, PAGE_READWRITE);
- return (ptr != 0)? ptr: MFAIL;
-}
-
-/* For direct MMAP, use MEM_TOP_DOWN to minimize interference */
-static FORCEINLINE void* win32direct_mmap(size_t size) {
- void* ptr = VirtualAlloc(0, size, MEM_RESERVE|MEM_COMMIT|MEM_TOP_DOWN,
- PAGE_READWRITE);
- return (ptr != 0)? ptr: MFAIL;
-}
-
-/* This function supports releasing coalesced segments */
-static FORCEINLINE int win32munmap(void* ptr, size_t size) {
- MEMORY_BASIC_INFORMATION minfo;
- char* cptr = (char*)ptr;
- while (size) {
- if (VirtualQuery(cptr, &minfo, sizeof(minfo)) == 0)
- return -1;
- if (minfo.BaseAddress != cptr || minfo.AllocationBase != cptr ||
- minfo.State != MEM_COMMIT || minfo.RegionSize > size)
- return -1;
- if (VirtualFree(cptr, 0, MEM_RELEASE) == 0)
- return -1;
- cptr += minfo.RegionSize;
- size -= minfo.RegionSize;
- }
- return 0;
-}
-
-#define MMAP_DEFAULT(s) win32mmap(s)
-#define MUNMAP_DEFAULT(a, s) win32munmap((a), (s))
-#define DIRECT_MMAP_DEFAULT(s) win32direct_mmap(s)
-#endif /* WIN32 */
-#endif /* HAVE_MMAP */
-
-#if HAVE_MREMAP
-#ifndef WIN32
-#define MREMAP_DEFAULT(addr, osz, nsz, mv) mremap((addr), (osz), (nsz), (mv))
-#endif /* WIN32 */
-#endif /* HAVE_MREMAP */
-
-
-/**
- * Define CALL_MORECORE
- */
-#if HAVE_MORECORE
- #ifdef MORECORE
- #define CALL_MORECORE(S) MORECORE(S)
- #else /* MORECORE */
- #define CALL_MORECORE(S) MORECORE_DEFAULT(S)
- #endif /* MORECORE */
-#else /* HAVE_MORECORE */
- #define CALL_MORECORE(S) MFAIL
-#endif /* HAVE_MORECORE */
-
-/**
- * Define CALL_MMAP/CALL_MUNMAP/CALL_DIRECT_MMAP
- */
-#if HAVE_MMAP
- #define IS_MMAPPED_BIT (SIZE_T_ONE)
- #define USE_MMAP_BIT (SIZE_T_ONE)
-
- #ifdef MMAP
- #define CALL_MMAP(s) MMAP(s)
- #else /* MMAP */
- #define CALL_MMAP(s) MMAP_DEFAULT(s)
- #endif /* MMAP */
- #ifdef MUNMAP
- #define CALL_MUNMAP(a, s) MUNMAP((a), (s))
- #else /* MUNMAP */
- #define CALL_MUNMAP(a, s) MUNMAP_DEFAULT((a), (s))
- #endif /* MUNMAP */
- #ifdef DIRECT_MMAP
- #define CALL_DIRECT_MMAP(s) DIRECT_MMAP(s)
- #else /* DIRECT_MMAP */
- #define CALL_DIRECT_MMAP(s) DIRECT_MMAP_DEFAULT(s)
- #endif /* DIRECT_MMAP */
-#else /* HAVE_MMAP */
- #define IS_MMAPPED_BIT (SIZE_T_ZERO)
- #define USE_MMAP_BIT (SIZE_T_ZERO)
-
- #define MMAP(s) MFAIL
- #define MUNMAP(a, s) (-1)
- #define DIRECT_MMAP(s) MFAIL
- #define CALL_DIRECT_MMAP(s) DIRECT_MMAP(s)
- #define CALL_MMAP(s) MMAP(s)
- #define CALL_MUNMAP(a, s) MUNMAP((a), (s))
-#endif /* HAVE_MMAP */
-
-/**
- * Define CALL_MREMAP
- */
-#if HAVE_MMAP && HAVE_MREMAP
- #ifdef MREMAP
- #define CALL_MREMAP(addr, osz, nsz, mv) MREMAP((addr), (osz), (nsz), (mv))
- #else /* MREMAP */
- #define CALL_MREMAP(addr, osz, nsz, mv) MREMAP_DEFAULT((addr), (osz), (nsz), (mv))
- #endif /* MREMAP */
-#else /* HAVE_MMAP && HAVE_MREMAP */
- #define CALL_MREMAP(addr, osz, nsz, mv) MFAIL
-#endif /* HAVE_MMAP && HAVE_MREMAP */
-
-/* mstate bit set if contiguous morecore disabled or failed */
-#define USE_NONCONTIGUOUS_BIT (4U)
-
-/* segment bit set in create_mspace_with_base */
-#define EXTERN_BIT (8U)
-
-
-/* --------------------------- Lock preliminaries ------------------------ */
-
-/*
- When locks are defined, there is one global lock, plus
- one per-mspace lock.
-
- The global lock_ensures that mparams.magic and other unique
- mparams values are initialized only once. It also protects
- sequences of calls to MORECORE. In many cases sys_alloc requires
- two calls, that should not be interleaved with calls by other
- threads. This does not protect against direct calls to MORECORE
- by other threads not using this lock, so there is still code to
- cope the best we can on interference.
-
- Per-mspace locks surround calls to malloc, free, etc. To enable use
- in layered extensions, per-mspace locks are reentrant.
-
- Because lock-protected regions generally have bounded times, it is
- OK to use the supplied simple spinlocks in the custom versions for
- x86.
-
- If USE_LOCKS is > 1, the definitions of lock routines here are
- bypassed, in which case you will need to define at least
- INITIAL_LOCK, ACQUIRE_LOCK, RELEASE_LOCK and possibly TRY_LOCK
- (which is not used in this malloc, but commonly needed in
- extensions.)
-*/
-
-#if USE_LOCKS == 1
-
-#if USE_SPIN_LOCKS
-#ifndef WIN32
-
-/* Custom pthread-style spin locks on x86 and x64 for gcc */
-struct pthread_mlock_t {
- volatile unsigned int l;
- volatile unsigned int c;
- volatile pthread_t threadid;
-};
-#define MLOCK_T struct pthread_mlock_t
-#define CURRENT_THREAD pthread_self()
-#define INITIAL_LOCK(sl) (memset(sl, 0, sizeof(MLOCK_T)), 0)
-#define ACQUIRE_LOCK(sl) pthread_acquire_lock(sl)
-#define RELEASE_LOCK(sl) pthread_release_lock(sl)
-#define TRY_LOCK(sl) pthread_try_lock(sl)
-#define SPINS_PER_YIELD 63
-
-static MLOCK_T malloc_global_mutex = { 0, 0, 0};
-
-static FORCEINLINE int pthread_acquire_lock (MLOCK_T *sl) {
- int spins = 0;
- volatile unsigned int* lp = &sl->l;
- for (;;) {
- if (*lp != 0) {
- if (sl->threadid == CURRENT_THREAD) {
- ++sl->c;
- return 0;
- }
- }
- else {
- /* place args to cmpxchgl in locals to evade oddities in some gccs */
- int cmp = 0;
- int val = 1;
- int ret;
- __asm__ __volatile__ ("lock; cmpxchgl %1, %2"
- : "=a" (ret)
- : "r" (val), "m" (*(lp)), "0"(cmp)
- : "memory", "cc");
- if (!ret) {
- assert(!sl->threadid);
- sl->c = 1;
- sl->threadid = CURRENT_THREAD;
- return 0;
- }
- if ((++spins & SPINS_PER_YIELD) == 0) {
-#if defined (__SVR4) && defined (__sun) /* solaris */
- thr_yield();
-#else
-#if defined(__linux__) || defined(__FreeBSD__) || defined(__APPLE__)
- sched_yield();
-#else /* no-op yield on unknown systems */
- ;
-#endif /* __linux__ || __FreeBSD__ || __APPLE__ */
-#endif /* solaris */
- }
- }
- }
-}
-
-static FORCEINLINE void pthread_release_lock (MLOCK_T *sl) {
- assert(sl->l != 0);
- assert(sl->threadid == CURRENT_THREAD);
- if (--sl->c == 0) {
- volatile unsigned int* lp = &sl->l;
- int prev = 0;
- int ret;
- sl->threadid = 0;
- __asm__ __volatile__ ("lock; xchgl %0, %1"
- : "=r" (ret)
- : "m" (*(lp)), "0"(prev)
- : "memory");
- }
-}
-
-static FORCEINLINE int pthread_try_lock (MLOCK_T *sl) {
- volatile unsigned int* lp = &sl->l;
- if (*lp != 0) {
- if (sl->threadid == CURRENT_THREAD) {
- ++sl->c;
- return 1;
- }
- }
- else {
- int cmp = 0;
- int val = 1;
- int ret;
- __asm__ __volatile__ ("lock; cmpxchgl %1, %2"
- : "=a" (ret)
- : "r" (val), "m" (*(lp)), "0"(cmp)
- : "memory", "cc");
- if (!ret) {
- assert(!sl->threadid);
- sl->c = 1;
- sl->threadid = CURRENT_THREAD;
- return 1;
- }
- }
- return 0;
-}
-
-
-#else /* WIN32 */
-/* Custom win32-style spin locks on x86 and x64 for MSC */
-struct win32_mlock_t
-{
- volatile long l;
- volatile unsigned int c;
- volatile long threadid;
-};
-
-static inline int return_0(int i) { return 0; }
-#define MLOCK_T struct win32_mlock_t
-#define CURRENT_THREAD win32_getcurrentthreadid()
-#define INITIAL_LOCK(sl) (memset(sl, 0, sizeof(MLOCK_T)), return_0(0))
-#define ACQUIRE_LOCK(sl) win32_acquire_lock(sl)
-#define RELEASE_LOCK(sl) win32_release_lock(sl)
-#define TRY_LOCK(sl) win32_try_lock(sl)
-#define SPINS_PER_YIELD 63
-
-static MLOCK_T malloc_global_mutex = { 0, 0, 0};
-
-static FORCEINLINE long win32_getcurrentthreadid(void) {
-#ifdef _MSC_VER
-#if defined(_M_IX86)
- long *threadstruct=(long *)__readfsdword(0x18);
- long threadid=threadstruct[0x24/sizeof(long)];
- return threadid;
-#elif defined(_M_X64)
- /* todo */
- return GetCurrentThreadId();
-#else
- return GetCurrentThreadId();
-#endif
-#else
- return GetCurrentThreadId();
-#endif
-}
-
-static FORCEINLINE int win32_acquire_lock (MLOCK_T *sl) {
- int spins = 0;
- for (;;) {
- if (sl->l != 0) {
- if (sl->threadid == CURRENT_THREAD) {
- ++sl->c;
- return 0;
- }
- }
- else {
- if (!interlockedexchange(&sl->l, 1)) {
- assert(!sl->threadid);
- sl->c=CURRENT_THREAD;
- sl->threadid = CURRENT_THREAD;
- sl->c = 1;
- return 0;
- }
- }
- if ((++spins & SPINS_PER_YIELD) == 0)
- SleepEx(0, FALSE);
- }
-}
-
-static FORCEINLINE void win32_release_lock (MLOCK_T *sl) {
- assert(sl->threadid == CURRENT_THREAD);
- assert(sl->l != 0);
- if (--sl->c == 0) {
- sl->threadid = 0;
- interlockedexchange (&sl->l, 0);
- }
-}
-
-static FORCEINLINE int win32_try_lock (MLOCK_T *sl) {
- if(sl->l != 0) {
- if (sl->threadid == CURRENT_THREAD) {
- ++sl->c;
- return 1;
- }
- }
- else {
- if (!interlockedexchange(&sl->l, 1)){
- assert(!sl->threadid);
- sl->threadid = CURRENT_THREAD;
- sl->c = 1;
- return 1;
- }
- }
- return 0;
-}
-
-#endif /* WIN32 */
-#else /* USE_SPIN_LOCKS */
-
-#ifndef WIN32
-/* pthreads-based locks */
-
-#define MLOCK_T pthread_mutex_t
-#define CURRENT_THREAD pthread_self()
-#define INITIAL_LOCK(sl) pthread_init_lock(sl)
-#define ACQUIRE_LOCK(sl) pthread_mutex_lock(sl)
-#define RELEASE_LOCK(sl) pthread_mutex_unlock(sl)
-#define TRY_LOCK(sl) (!pthread_mutex_trylock(sl))
-
-static MLOCK_T malloc_global_mutex = PTHREAD_MUTEX_INITIALIZER;
-
-/* Cope with old-style linux recursive lock initialization by adding */
-/* skipped internal declaration from pthread.h */
-#ifdef linux
-#ifndef PTHREAD_MUTEX_RECURSIVE
-extern int pthread_mutexattr_setkind_np __P ((pthread_mutexattr_t *__attr,
- int __kind));
-#define PTHREAD_MUTEX_RECURSIVE PTHREAD_MUTEX_RECURSIVE_NP
-#define pthread_mutexattr_settype(x,y) pthread_mutexattr_setkind_np(x,y)
-#endif
-#endif
-
-static int pthread_init_lock (MLOCK_T *sl) {
- pthread_mutexattr_t attr;
- if (pthread_mutexattr_init(&attr)) return 1;
- if (pthread_mutexattr_settype(&attr, PTHREAD_MUTEX_RECURSIVE)) return 1;
- if (pthread_mutex_init(sl, &attr)) return 1;
- if (pthread_mutexattr_destroy(&attr)) return 1;
- return 0;
-}
-
-#else /* WIN32 */
-/* Win32 critical sections */
-#define MLOCK_T CRITICAL_SECTION
-#define CURRENT_THREAD GetCurrentThreadId()
-#define INITIAL_LOCK(s) (!InitializeCriticalSectionAndSpinCount((s), 0x80000000|4000))
-#define ACQUIRE_LOCK(s) (EnterCriticalSection(s), 0)
-#define RELEASE_LOCK(s) LeaveCriticalSection(s)
-#define TRY_LOCK(s) TryEnterCriticalSection(s)
-#define NEED_GLOBAL_LOCK_INIT
-
-static MLOCK_T malloc_global_mutex;
-static volatile long malloc_global_mutex_status;
-
-/* Use spin loop to initialize global lock */
-static void init_malloc_global_mutex() {
- for (;;) {
- long stat = malloc_global_mutex_status;
- if (stat > 0)
- return;
- /* transition to < 0 while initializing, then to > 0) */
- if (stat == 0 &&
- interlockedcompareexchange(&malloc_global_mutex_status, -1, 0) == 0) {
- InitializeCriticalSection(&malloc_global_mutex);
- interlockedexchange(&malloc_global_mutex_status,1);
- return;
- }
- SleepEx(0, FALSE);
- }
-}
-
-#endif /* WIN32 */
-#endif /* USE_SPIN_LOCKS */
-#endif /* USE_LOCKS == 1 */
-
-/* ----------------------- User-defined locks ------------------------ */
-
-#if USE_LOCKS > 1
-/* Define your own lock implementation here */
-/* #define INITIAL_LOCK(sl) ... */
-/* #define ACQUIRE_LOCK(sl) ... */
-/* #define RELEASE_LOCK(sl) ... */
-/* #define TRY_LOCK(sl) ... */
-/* static MLOCK_T malloc_global_mutex = ... */
-#endif /* USE_LOCKS > 1 */
-
-/* ----------------------- Lock-based state ------------------------ */
-
-#if USE_LOCKS
-#define USE_LOCK_BIT (2U)
-#else /* USE_LOCKS */
-#define USE_LOCK_BIT (0U)
-#define INITIAL_LOCK(l)
-#endif /* USE_LOCKS */
-
-#if USE_LOCKS
-#define ACQUIRE_MALLOC_GLOBAL_LOCK() ACQUIRE_LOCK(&malloc_global_mutex);
-#define RELEASE_MALLOC_GLOBAL_LOCK() RELEASE_LOCK(&malloc_global_mutex);
-#else /* USE_LOCKS */
-#define ACQUIRE_MALLOC_GLOBAL_LOCK()
-#define RELEASE_MALLOC_GLOBAL_LOCK()
-#endif /* USE_LOCKS */
-
-
-/* ----------------------- Chunk representations ------------------------ */
-
-/*
- (The following includes lightly edited explanations by Colin Plumb.)
-
- The malloc_chunk declaration below is misleading (but accurate and
- necessary). It declares a "view" into memory allowing access to
- necessary fields at known offsets from a given base.
-
- Chunks of memory are maintained using a `boundary tag' method as
- originally described by Knuth. (See the paper by Paul Wilson
- ftp://ftp.cs.utexas.edu/pub/garbage/allocsrv.ps for a survey of such
- techniques.) Sizes of free chunks are stored both in the front of
- each chunk and at the end. This makes consolidating fragmented
- chunks into bigger chunks fast. The head fields also hold bits
- representing whether chunks are free or in use.
-
- Here are some pictures to make it clearer. They are "exploded" to
- show that the state of a chunk can be thought of as extending from
- the high 31 bits of the head field of its header through the
- prev_foot and PINUSE_BIT bit of the following chunk header.
-
- A chunk that's in use looks like:
-
- chunk-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- | Size of previous chunk (if P = 0) |
- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |P|
- | Size of this chunk 1| +-+
- mem-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- | |
- +- -+
- | |
- +- -+
- | :
- +- size - sizeof(size_t) available payload bytes -+
- : |
- chunk-> +- -+
- | |
- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |1|
- | Size of next chunk (may or may not be in use) | +-+
- mem-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
-
- And if it's free, it looks like this:
-
- chunk-> +- -+
- | User payload (must be in use, or we would have merged!) |
- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |P|
- | Size of this chunk 0| +-+
- mem-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- | Next pointer |
- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- | Prev pointer |
- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- | :
- +- size - sizeof(struct chunk) unused bytes -+
- : |
- chunk-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- | Size of this chunk |
- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |0|
- | Size of next chunk (must be in use, or we would have merged)| +-+
- mem-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- | :
- +- User payload -+
- : |
- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- |0|
- +-+
- Note that since we always merge adjacent free chunks, the chunks
- adjacent to a free chunk must be in use.
-
- Given a pointer to a chunk (which can be derived trivially from the
- payload pointer) we can, in O(1) time, find out whether the adjacent
- chunks are free, and if so, unlink them from the lists that they
- are on and merge them with the current chunk.
-
- Chunks always begin on even word boundaries, so the mem portion
- (which is returned to the user) is also on an even word boundary, and
- thus at least double-word aligned.
-
- The P (PINUSE_BIT) bit, stored in the unused low-order bit of the
- chunk size (which is always a multiple of two words), is an in-use
- bit for the *previous* chunk. If that bit is *clear*, then the
- word before the current chunk size contains the previous chunk
- size, and can be used to find the front of the previous chunk.
- The very first chunk allocated always has this bit set, preventing
- access to non-existent (or non-owned) memory. If pinuse is set for
- any given chunk, then you CANNOT determine the size of the
- previous chunk, and might even get a memory addressing fault when
- trying to do so.
-
- The C (CINUSE_BIT) bit, stored in the unused second-lowest bit of
- the chunk size redundantly records whether the current chunk is
- inuse. This redundancy enables usage checks within free and realloc,
- and reduces indirection when freeing and consolidating chunks.
-
- Each freshly allocated chunk must have both cinuse and pinuse set.
- That is, each allocated chunk borders either a previously allocated
- and still in-use chunk, or the base of its memory arena. This is
- ensured by making all allocations from the `lowest' part of any
- found chunk. Further, no free chunk physically borders another one,
- so each free chunk is known to be preceded and followed by either
- inuse chunks or the ends of memory.
-
- Note that the `foot' of the current chunk is actually represented
- as the prev_foot of the NEXT chunk. This makes it easier to
- deal with alignments etc but can be very confusing when trying
- to extend or adapt this code.
-
- The exceptions to all this are
-
- 1. The special chunk `top' is the top-most available chunk (i.e.,
- the one bordering the end of available memory). It is treated
- specially. Top is never included in any bin, is used only if
- no other chunk is available, and is released back to the
- system if it is very large (see M_TRIM_THRESHOLD). In effect,
- the top chunk is treated as larger (and thus less well
- fitting) than any other available chunk. The top chunk
- doesn't update its trailing size field since there is no next
- contiguous chunk that would have to index off it. However,
- space is still allocated for it (TOP_FOOT_SIZE) to enable
- separation or merging when space is extended.
-
- 3. Chunks allocated via mmap, which have the lowest-order bit
- (IS_MMAPPED_BIT) set in their prev_foot fields, and do not set
- PINUSE_BIT in their head fields. Because they are allocated
- one-by-one, each must carry its own prev_foot field, which is
- also used to hold the offset this chunk has within its mmapped
- region, which is needed to preserve alignment. Each mmapped
- chunk is trailed by the first two fields of a fake next-chunk
- for sake of usage checks.
-
-*/
-
-struct malloc_chunk {
- size_t prev_foot; /* Size of previous chunk (if free). */
- size_t head; /* Size and inuse bits. */
- struct malloc_chunk* fd; /* double links -- used only if free. */
- struct malloc_chunk* bk;
-};
-
-typedef struct malloc_chunk mchunk;
-typedef struct malloc_chunk* mchunkptr;
-typedef struct malloc_chunk* sbinptr; /* The type of bins of chunks */
-typedef unsigned int bindex_t; /* Described below */
-typedef unsigned int binmap_t; /* Described below */
-typedef unsigned int flag_t; /* The type of various bit flag sets */
-
-/* ------------------- Chunks sizes and alignments ----------------------- */
-
-#define MCHUNK_SIZE (sizeof(mchunk))
-
-#if FOOTERS
-#define CHUNK_OVERHEAD (TWO_SIZE_T_SIZES)
-#else /* FOOTERS */
-#define CHUNK_OVERHEAD (SIZE_T_SIZE)
-#endif /* FOOTERS */
-
-/* MMapped chunks need a second word of overhead ... */
-#define MMAP_CHUNK_OVERHEAD (TWO_SIZE_T_SIZES)
-/* ... and additional padding for fake next-chunk at foot */
-#define MMAP_FOOT_PAD (FOUR_SIZE_T_SIZES)
-
-/* The smallest size we can malloc is an aligned minimal chunk */
-#define MIN_CHUNK_SIZE\
- ((MCHUNK_SIZE + CHUNK_ALIGN_MASK) & ~CHUNK_ALIGN_MASK)
-
-/* conversion from malloc headers to user pointers, and back */
-#define chunk2mem(p) ((void*)((char*)(p) + TWO_SIZE_T_SIZES))
-#define mem2chunk(mem) ((mchunkptr)((char*)(mem) - TWO_SIZE_T_SIZES))
-/* chunk associated with aligned address A */
-#define align_as_chunk(A) (mchunkptr)((A) + align_offset(chunk2mem(A)))
-
-/* Bounds on request (not chunk) sizes. */
-#define MAX_REQUEST ((-MIN_CHUNK_SIZE) << 2)
-#define MIN_REQUEST (MIN_CHUNK_SIZE - CHUNK_OVERHEAD - SIZE_T_ONE)
-
-/* pad request bytes into a usable size */
-#define pad_request(req) \
- (((req) + CHUNK_OVERHEAD + CHUNK_ALIGN_MASK) & ~CHUNK_ALIGN_MASK)
-
-/* pad request, checking for minimum (but not maximum) */
-#define request2size(req) \
- (((req) < MIN_REQUEST)? MIN_CHUNK_SIZE : pad_request(req))
-
-
-/* ------------------ Operations on head and foot fields ----------------- */
-
-/*
- The head field of a chunk is or'ed with PINUSE_BIT when previous
- adjacent chunk in use, and or'ed with CINUSE_BIT if this chunk is in
- use. If the chunk was obtained with mmap, the prev_foot field has
- IS_MMAPPED_BIT set, otherwise holding the offset of the base of the
- mmapped region to the base of the chunk.
-
- FLAG4_BIT is not used by this malloc, but might be useful in extensions.
-*/
-
-#define PINUSE_BIT (SIZE_T_ONE)
-#define CINUSE_BIT (SIZE_T_TWO)
-#define FLAG4_BIT (SIZE_T_FOUR)
-#define INUSE_BITS (PINUSE_BIT|CINUSE_BIT)
-#define FLAG_BITS (PINUSE_BIT|CINUSE_BIT|FLAG4_BIT)
-
-/* Head value for fenceposts */
-#define FENCEPOST_HEAD (INUSE_BITS|SIZE_T_SIZE)
-
-/* extraction of fields from head words */
-#define cinuse(p) ((p)->head & CINUSE_BIT)
-#define pinuse(p) ((p)->head & PINUSE_BIT)
-#define chunksize(p) ((p)->head & ~(FLAG_BITS))
-
-#define clear_pinuse(p) ((p)->head &= ~PINUSE_BIT)
-#define clear_cinuse(p) ((p)->head &= ~CINUSE_BIT)
-
-/* Treat space at ptr +/- offset as a chunk */
-#define chunk_plus_offset(p, s) ((mchunkptr)(((char*)(p)) + (s)))
-#define chunk_minus_offset(p, s) ((mchunkptr)(((char*)(p)) - (s)))
-
-/* Ptr to next or previous physical malloc_chunk. */
-#define next_chunk(p) ((mchunkptr)( ((char*)(p)) + ((p)->head & ~FLAG_BITS)))
-#define prev_chunk(p) ((mchunkptr)( ((char*)(p)) - ((p)->prev_foot) ))
-
-/* extract next chunk's pinuse bit */
-#define next_pinuse(p) ((next_chunk(p)->head) & PINUSE_BIT)
-
-/* Get/set size at footer */
-#define get_foot(p, s) (((mchunkptr)((char*)(p) + (s)))->prev_foot)
-#define set_foot(p, s) (((mchunkptr)((char*)(p) + (s)))->prev_foot = (s))
-
-/* Set size, pinuse bit, and foot */
-#define set_size_and_pinuse_of_free_chunk(p, s)\
- ((p)->head = (s|PINUSE_BIT), set_foot(p, s))
-
-/* Set size, pinuse bit, foot, and clear next pinuse */
-#define set_free_with_pinuse(p, s, n)\
- (clear_pinuse(n), set_size_and_pinuse_of_free_chunk(p, s))
-
-#define is_mmapped(p)\
- (!((p)->head & PINUSE_BIT) && ((p)->prev_foot & IS_MMAPPED_BIT))
-
-/* Get the internal overhead associated with chunk p */
-#define overhead_for(p)\
- (is_mmapped(p)? MMAP_CHUNK_OVERHEAD : CHUNK_OVERHEAD)
-
-/* Return true if malloced space is not necessarily cleared */
-#if MMAP_CLEARS
-#define calloc_must_clear(p) (!is_mmapped(p))
-#else /* MMAP_CLEARS */
-#define calloc_must_clear(p) (1)
-#endif /* MMAP_CLEARS */
-
/* ---------------------- Overlaid data structures ----------------------- */
/*
--
gitgitgadget
^ permalink raw reply related
* [PATCH v3 6/6] to be squashed into 3/6 (chunk 3 of 3)
From: Johannes Schindelin via GitGitGadget @ 2026-05-08 12:51 UTC (permalink / raw)
To: git; +Cc: Patrick Steinhardt, Johannes Schindelin, Johannes Schindelin
In-Reply-To: <pull.2104.v3.git.1778244661.gitgitgadget@gmail.com>
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Assisted-by: Opus 4.7
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
compat/nedmalloc/malloc.c.h | 1827 -----------------------------------
1 file changed, 1827 deletions(-)
delete mode 100644 compat/nedmalloc/malloc.c.h
diff --git a/compat/nedmalloc/malloc.c.h b/compat/nedmalloc/malloc.c.h
deleted file mode 100644
index 0c663cf49c..0000000000
--- a/compat/nedmalloc/malloc.c.h
+++ /dev/null
@@ -1,1827 +0,0 @@
-/* -------------------------- System allocation -------------------------- */
-
-/* Get memory from system using MORECORE or MMAP */
-static void* sys_alloc(mstate m, size_t nb) {
- char* tbase = CMFAIL;
- size_t tsize = 0;
- flag_t mmap_flag = 0;
-
- ensure_initialization();
-
- /* Directly map large chunks */
- if (use_mmap(m) && nb >= mparams.mmap_threshold) {
- void* mem = mmap_alloc(m, nb);
- if (mem != 0)
- return mem;
- }
-
- /*
- Try getting memory in any of three ways (in most-preferred to
- least-preferred order):
- 1. A call to MORECORE that can normally contiguously extend memory.
- (disabled if not MORECORE_CONTIGUOUS or not HAVE_MORECORE or
- main space is mmapped or a previous contiguous call failed)
- 2. A call to MMAP new space (disabled if not HAVE_MMAP).
- Note that under the default settings, if MORECORE is unable to
- fulfill a request, and HAVE_MMAP is true, then mmap is
- used as a noncontiguous system allocator. This is a useful backup
- strategy for systems with holes in address spaces -- in this case
- sbrk cannot contiguously expand the heap, but mmap may be able to
- find space.
- 3. A call to MORECORE that cannot usually contiguously extend memory.
- (disabled if not HAVE_MORECORE)
-
- In all cases, we need to request enough bytes from system to ensure
- we can malloc nb bytes upon success, so pad with enough space for
- top_foot, plus alignment-pad to make sure we don't lose bytes if
- not on boundary, and round this up to a granularity unit.
- */
-
- if (MORECORE_CONTIGUOUS && !use_noncontiguous(m)) {
- char* br = CMFAIL;
- msegmentptr ss = (m->top == 0)? 0 : segment_holding(m, (char*)m->top);
- size_t asize = 0;
- ACQUIRE_MALLOC_GLOBAL_LOCK();
-
- if (ss == 0) { /* First time through or recovery */
- char* base = (char*)CALL_MORECORE(0);
- if (base != CMFAIL) {
- asize = granularity_align(nb + SYS_ALLOC_PADDING);
- /* Adjust to end on a page boundary */
- if (!is_page_aligned(base))
- asize += (page_align((size_t)base) - (size_t)base);
- /* Can't call MORECORE if size is negative when treated as signed */
- if (asize < HALF_MAX_SIZE_T &&
- (br = (char*)(CALL_MORECORE(asize))) == base) {
- tbase = base;
- tsize = asize;
- }
- }
- }
- else {
- /* Subtract out existing available top space from MORECORE request. */
- asize = granularity_align(nb - m->topsize + SYS_ALLOC_PADDING);
- /* Use mem here only if it did continuously extend old space */
- if (asize < HALF_MAX_SIZE_T &&
- (br = (char*)(CALL_MORECORE(asize))) == ss->base+ss->size) {
- tbase = br;
- tsize = asize;
- }
- }
-
- if (tbase == CMFAIL) { /* Cope with partial failure */
- if (br != CMFAIL) { /* Try to use/extend the space we did get */
- if (asize < HALF_MAX_SIZE_T &&
- asize < nb + SYS_ALLOC_PADDING) {
- size_t esize = granularity_align(nb + SYS_ALLOC_PADDING - asize);
- if (esize < HALF_MAX_SIZE_T) {
- char* end = (char*)CALL_MORECORE(esize);
- if (end != CMFAIL)
- asize += esize;
- else { /* Can't use; try to release */
- (void) CALL_MORECORE(-asize);
- br = CMFAIL;
- }
- }
- }
- }
- if (br != CMFAIL) { /* Use the space we did get */
- tbase = br;
- tsize = asize;
- }
- else
- disable_contiguous(m); /* Don't try contiguous path in the future */
- }
-
- RELEASE_MALLOC_GLOBAL_LOCK();
- }
-
- if (HAVE_MMAP && tbase == CMFAIL) { /* Try MMAP */
- size_t rsize = granularity_align(nb + SYS_ALLOC_PADDING);
- if (rsize > nb) { /* Fail if wraps around zero */
- char* mp = (char*)(CALL_MMAP(rsize));
- if (mp != CMFAIL) {
- tbase = mp;
- tsize = rsize;
- mmap_flag = IS_MMAPPED_BIT;
- }
- }
- }
-
- if (HAVE_MORECORE && tbase == CMFAIL) { /* Try noncontiguous MORECORE */
- size_t asize = granularity_align(nb + SYS_ALLOC_PADDING);
- if (asize < HALF_MAX_SIZE_T) {
- char* br = CMFAIL;
- char* end = CMFAIL;
- ACQUIRE_MALLOC_GLOBAL_LOCK();
- br = (char*)(CALL_MORECORE(asize));
- end = (char*)(CALL_MORECORE(0));
- RELEASE_MALLOC_GLOBAL_LOCK();
- if (br != CMFAIL && end != CMFAIL && br < end) {
- size_t ssize = end - br;
- if (ssize > nb + TOP_FOOT_SIZE) {
- tbase = br;
- tsize = ssize;
- }
- }
- }
- }
-
- if (tbase != CMFAIL) {
-
- if ((m->footprint += tsize) > m->max_footprint)
- m->max_footprint = m->footprint;
-
- if (!is_initialized(m)) { /* first-time initialization */
- m->seg.base = m->least_addr = tbase;
- m->seg.size = tsize;
- m->seg.sflags = mmap_flag;
- m->magic = mparams.magic;
- m->release_checks = MAX_RELEASE_CHECK_RATE;
- init_bins(m);
-#if !ONLY_MSPACES
- if (is_global(m))
- init_top(m, (mchunkptr)tbase, tsize - TOP_FOOT_SIZE);
- else
-#endif
- {
- /* Offset top by embedded malloc_state */
- mchunkptr mn = next_chunk(mem2chunk(m));
- init_top(m, mn, (size_t)((tbase + tsize) - (char*)mn) -TOP_FOOT_SIZE);
- }
- }
-
- else {
- /* Try to merge with an existing segment */
- msegmentptr sp = &m->seg;
- /* Only consider most recent segment if traversal suppressed */
- while (sp != 0 && tbase != sp->base + sp->size)
- sp = (NO_SEGMENT_TRAVERSAL) ? 0 : sp->next;
- if (sp != 0 &&
- !is_extern_segment(sp) &&
- (sp->sflags & IS_MMAPPED_BIT) == mmap_flag &&
- segment_holds(sp, m->top)) { /* append */
- sp->size += tsize;
- init_top(m, m->top, m->topsize + tsize);
- }
- else {
- if (tbase < m->least_addr)
- m->least_addr = tbase;
- sp = &m->seg;
- while (sp != 0 && sp->base != tbase + tsize)
- sp = (NO_SEGMENT_TRAVERSAL) ? 0 : sp->next;
- if (sp != 0 &&
- !is_extern_segment(sp) &&
- (sp->sflags & IS_MMAPPED_BIT) == mmap_flag) {
- char* oldbase = sp->base;
- sp->base = tbase;
- sp->size += tsize;
- return prepend_alloc(m, tbase, oldbase, nb);
- }
- else
- add_segment(m, tbase, tsize, mmap_flag);
- }
- }
-
- if (nb < m->topsize) { /* Allocate from new or extended top space */
- size_t rsize = m->topsize -= nb;
- mchunkptr p = m->top;
- mchunkptr r = m->top = chunk_plus_offset(p, nb);
- r->head = rsize | PINUSE_BIT;
- set_size_and_pinuse_of_inuse_chunk(m, p, nb);
- check_top_chunk(m, m->top);
- check_malloced_chunk(m, chunk2mem(p), nb);
- return chunk2mem(p);
- }
- }
-
- MALLOC_FAILURE_ACTION;
- return 0;
-}
-
-/* ----------------------- system deallocation -------------------------- */
-
-/* Unmap and unlink any mmapped segments that don't contain used chunks */
-static size_t release_unused_segments(mstate m) {
- size_t released = 0;
- int nsegs = 0;
- msegmentptr pred = &m->seg;
- msegmentptr sp = pred->next;
- while (sp != 0) {
- char* base = sp->base;
- size_t size = sp->size;
- msegmentptr next = sp->next;
- ++nsegs;
- if (is_mmapped_segment(sp) && !is_extern_segment(sp)) {
- mchunkptr p = align_as_chunk(base);
- size_t psize = chunksize(p);
- /* Can unmap if first chunk holds entire segment and not pinned */
- if (!cinuse(p) && (char*)p + psize >= base + size - TOP_FOOT_SIZE) {
- tchunkptr tp = (tchunkptr)p;
- assert(segment_holds(sp, (char*)sp));
- if (p == m->dv) {
- m->dv = 0;
- m->dvsize = 0;
- }
- else {
- unlink_large_chunk(m, tp);
- }
- if (CALL_MUNMAP(base, size) == 0) {
- released += size;
- m->footprint -= size;
- /* unlink obsoleted record */
- sp = pred;
- sp->next = next;
- }
- else { /* back out if cannot unmap */
- insert_large_chunk(m, tp, psize);
- }
- }
- }
- if (NO_SEGMENT_TRAVERSAL) /* scan only first segment */
- break;
- pred = sp;
- sp = next;
- }
- /* Reset check counter */
- m->release_checks = ((nsegs > MAX_RELEASE_CHECK_RATE)?
- nsegs : MAX_RELEASE_CHECK_RATE);
- return released;
-}
-
-static int sys_trim(mstate m, size_t pad) {
- size_t released = 0;
- ensure_initialization();
- if (pad < MAX_REQUEST && is_initialized(m)) {
- pad += TOP_FOOT_SIZE; /* ensure enough room for segment overhead */
-
- if (m->topsize > pad) {
- /* Shrink top space in granularity-size units, keeping at least one */
- size_t unit = mparams.granularity;
- size_t extra = ((m->topsize - pad + (unit - SIZE_T_ONE)) / unit -
- SIZE_T_ONE) * unit;
- msegmentptr sp = segment_holding(m, (char*)m->top);
-
- if (!is_extern_segment(sp)) {
- if (is_mmapped_segment(sp)) {
- if (HAVE_MMAP &&
- sp->size >= extra &&
- !has_segment_link(m, sp)) { /* can't shrink if pinned */
- size_t newsize = sp->size - extra;
- /* Prefer mremap, fall back to munmap */
- if ((CALL_MREMAP(sp->base, sp->size, newsize, 0) != MFAIL) ||
- (CALL_MUNMAP(sp->base + newsize, extra) == 0)) {
- released = extra;
- }
- }
- }
- else if (HAVE_MORECORE) {
- if (extra >= HALF_MAX_SIZE_T) /* Avoid wrapping negative */
- extra = (HALF_MAX_SIZE_T) + SIZE_T_ONE - unit;
- ACQUIRE_MALLOC_GLOBAL_LOCK();
- {
- /* Make sure end of memory is where we last set it. */
- char* old_br = (char*)(CALL_MORECORE(0));
- if (old_br == sp->base + sp->size) {
- char* rel_br = (char*)(CALL_MORECORE(-extra));
- char* new_br = (char*)(CALL_MORECORE(0));
- if (rel_br != CMFAIL && new_br < old_br)
- released = old_br - new_br;
- }
- }
- RELEASE_MALLOC_GLOBAL_LOCK();
- }
- }
-
- if (released != 0) {
- sp->size -= released;
- m->footprint -= released;
- init_top(m, m->top, m->topsize - released);
- check_top_chunk(m, m->top);
- }
- }
-
- /* Unmap any unused mmapped segments */
- if (HAVE_MMAP)
- released += release_unused_segments(m);
-
- /* On failure, disable autotrim to avoid repeated failed future calls */
- if (released == 0 && m->topsize > m->trim_check)
- m->trim_check = MAX_SIZE_T;
- }
-
- return (released != 0)? 1 : 0;
-}
-
-
-/* ---------------------------- malloc support --------------------------- */
-
-/* allocate a large request from the best fitting chunk in a treebin */
-static void* tmalloc_large(mstate m, size_t nb) {
- tchunkptr v = 0;
- size_t rsize = -nb; /* Unsigned negation */
- tchunkptr t;
- bindex_t idx;
- compute_tree_index(nb, idx);
- if ((t = *treebin_at(m, idx)) != 0) {
- /* Traverse tree for this bin looking for node with size == nb */
- size_t sizebits = nb << leftshift_for_tree_index(idx);
- tchunkptr rst = 0; /* The deepest untaken right subtree */
- for (;;) {
- tchunkptr rt;
- size_t trem = chunksize(t) - nb;
- if (trem < rsize) {
- v = t;
- if ((rsize = trem) == 0)
- break;
- }
- rt = t->child[1];
- t = t->child[(sizebits >> (SIZE_T_BITSIZE-SIZE_T_ONE)) & 1];
- if (rt != 0 && rt != t)
- rst = rt;
- if (t == 0) {
- t = rst; /* set t to least subtree holding sizes > nb */
- break;
- }
- sizebits <<= 1;
- }
- }
- if (t == 0 && v == 0) { /* set t to root of next non-empty treebin */
- binmap_t leftbits = left_bits(idx2bit(idx)) & m->treemap;
- if (leftbits != 0) {
- bindex_t i;
- binmap_t leastbit = least_bit(leftbits);
- compute_bit2idx(leastbit, i);
- t = *treebin_at(m, i);
- }
- }
-
- while (t != 0) { /* find smallest of tree or subtree */
- size_t trem = chunksize(t) - nb;
- if (trem < rsize) {
- rsize = trem;
- v = t;
- }
- t = leftmost_child(t);
- }
-
- /* If dv is a better fit, return 0 so malloc will use it */
- if (v != 0 && rsize < (size_t)(m->dvsize - nb)) {
- if (RTCHECK(ok_address(m, v))) { /* split */
- mchunkptr r = chunk_plus_offset(v, nb);
- assert(chunksize(v) == rsize + nb);
- if (RTCHECK(ok_next(v, r))) {
- unlink_large_chunk(m, v);
- if (rsize < MIN_CHUNK_SIZE)
- set_inuse_and_pinuse(m, v, (rsize + nb));
- else {
- set_size_and_pinuse_of_inuse_chunk(m, v, nb);
- set_size_and_pinuse_of_free_chunk(r, rsize);
- insert_chunk(m, r, rsize);
- }
- return chunk2mem(v);
- }
- }
- CORRUPTION_ERROR_ACTION(m);
- }
- return 0;
-}
-
-/* allocate a small request from the best fitting chunk in a treebin */
-static void* tmalloc_small(mstate m, size_t nb) {
- tchunkptr t, v;
- size_t rsize;
- bindex_t i;
- binmap_t leastbit = least_bit(m->treemap);
- compute_bit2idx(leastbit, i);
- v = t = *treebin_at(m, i);
- rsize = chunksize(t) - nb;
-
- while ((t = leftmost_child(t)) != 0) {
- size_t trem = chunksize(t) - nb;
- if (trem < rsize) {
- rsize = trem;
- v = t;
- }
- }
-
- if (RTCHECK(ok_address(m, v))) {
- mchunkptr r = chunk_plus_offset(v, nb);
- assert(chunksize(v) == rsize + nb);
- if (RTCHECK(ok_next(v, r))) {
- unlink_large_chunk(m, v);
- if (rsize < MIN_CHUNK_SIZE)
- set_inuse_and_pinuse(m, v, (rsize + nb));
- else {
- set_size_and_pinuse_of_inuse_chunk(m, v, nb);
- set_size_and_pinuse_of_free_chunk(r, rsize);
- replace_dv(m, r, rsize);
- }
- return chunk2mem(v);
- }
- }
-
- CORRUPTION_ERROR_ACTION(m);
- return 0;
-}
-
-/* --------------------------- realloc support --------------------------- */
-
-static void* internal_realloc(mstate m, void* oldmem, size_t bytes) {
- if (bytes >= MAX_REQUEST) {
- MALLOC_FAILURE_ACTION;
- return 0;
- }
- if (!PREACTION(m)) {
- mchunkptr oldp = mem2chunk(oldmem);
- size_t oldsize = chunksize(oldp);
- mchunkptr next = chunk_plus_offset(oldp, oldsize);
- mchunkptr newp = 0;
- void* extra = 0;
-
- /* Try to either shrink or extend into top. Else malloc-copy-free */
-
- if (RTCHECK(ok_address(m, oldp) && ok_cinuse(oldp) &&
- ok_next(oldp, next) && ok_pinuse(next))) {
- size_t nb = request2size(bytes);
- if (is_mmapped(oldp))
- newp = mmap_resize(m, oldp, nb);
- else if (oldsize >= nb) { /* already big enough */
- size_t rsize = oldsize - nb;
- newp = oldp;
- if (rsize >= MIN_CHUNK_SIZE) {
- mchunkptr remainder = chunk_plus_offset(newp, nb);
- set_inuse(m, newp, nb);
- set_inuse(m, remainder, rsize);
- extra = chunk2mem(remainder);
- }
- }
- else if (next == m->top && oldsize + m->topsize > nb) {
- /* Expand into top */
- size_t newsize = oldsize + m->topsize;
- size_t newtopsize = newsize - nb;
- mchunkptr newtop = chunk_plus_offset(oldp, nb);
- set_inuse(m, oldp, nb);
- newtop->head = newtopsize |PINUSE_BIT;
- m->top = newtop;
- m->topsize = newtopsize;
- newp = oldp;
- }
- }
- else {
- USAGE_ERROR_ACTION(m, oldmem);
- POSTACTION(m);
- return 0;
- }
-
- POSTACTION(m);
-
- if (newp != 0) {
- if (extra != 0) {
- internal_free(m, extra);
- }
- check_inuse_chunk(m, newp);
- return chunk2mem(newp);
- }
- else {
- void* newmem = internal_malloc(m, bytes);
- if (newmem != 0) {
- size_t oc = oldsize - overhead_for(oldp);
- memcpy(newmem, oldmem, (oc < bytes)? oc : bytes);
- internal_free(m, oldmem);
- }
- return newmem;
- }
- }
- return 0;
-}
-
-/* --------------------------- memalign support -------------------------- */
-
-static void* internal_memalign(mstate m, size_t alignment, size_t bytes) {
- if (alignment <= MALLOC_ALIGNMENT) /* Can just use malloc */
- return internal_malloc(m, bytes);
- if (alignment < MIN_CHUNK_SIZE) /* must be at least a minimum chunk size */
- alignment = MIN_CHUNK_SIZE;
- if ((alignment & (alignment-SIZE_T_ONE)) != 0) {/* Ensure a power of 2 */
- size_t a = MALLOC_ALIGNMENT << 1;
- while (a < alignment) a <<= 1;
- alignment = a;
- }
-
- if (bytes >= MAX_REQUEST - alignment) {
- if (m != 0) { /* Test isn't needed but avoids compiler warning */
- MALLOC_FAILURE_ACTION;
- }
- }
- else {
- size_t nb = request2size(bytes);
- size_t req = nb + alignment + MIN_CHUNK_SIZE - CHUNK_OVERHEAD;
- char* mem = (char*)internal_malloc(m, req);
- if (mem != 0) {
- void* leader = 0;
- void* trailer = 0;
- mchunkptr p = mem2chunk(mem);
-
- if (PREACTION(m)) return 0;
- if ((((size_t)(mem)) % alignment) != 0) { /* misaligned */
- /*
- Find an aligned spot inside chunk. Since we need to give
- back leading space in a chunk of at least MIN_CHUNK_SIZE, if
- the first calculation places us at a spot with less than
- MIN_CHUNK_SIZE leader, we can move to the next aligned spot.
- We've allocated enough total room so that this is always
- possible.
- */
- char* br = (char*)mem2chunk((size_t)(((size_t)(mem +
- alignment -
- SIZE_T_ONE)) &
- -alignment));
- char* pos = ((size_t)(br - (char*)(p)) >= MIN_CHUNK_SIZE)?
- br : br+alignment;
- mchunkptr newp = (mchunkptr)pos;
- size_t leadsize = pos - (char*)(p);
- size_t newsize = chunksize(p) - leadsize;
-
- if (is_mmapped(p)) { /* For mmapped chunks, just adjust offset */
- newp->prev_foot = p->prev_foot + leadsize;
- newp->head = (newsize|CINUSE_BIT);
- }
- else { /* Otherwise, give back leader, use the rest */
- set_inuse(m, newp, newsize);
- set_inuse(m, p, leadsize);
- leader = chunk2mem(p);
- }
- p = newp;
- }
-
- /* Give back spare room at the end */
- if (!is_mmapped(p)) {
- size_t size = chunksize(p);
- if (size > nb + MIN_CHUNK_SIZE) {
- size_t remainder_size = size - nb;
- mchunkptr remainder = chunk_plus_offset(p, nb);
- set_inuse(m, p, nb);
- set_inuse(m, remainder, remainder_size);
- trailer = chunk2mem(remainder);
- }
- }
-
- assert (chunksize(p) >= nb);
- assert((((size_t)(chunk2mem(p))) % alignment) == 0);
- check_inuse_chunk(m, p);
- POSTACTION(m);
- if (leader != 0) {
- internal_free(m, leader);
- }
- if (trailer != 0) {
- internal_free(m, trailer);
- }
- return chunk2mem(p);
- }
- }
- return 0;
-}
-
-/* ------------------------ comalloc/coalloc support --------------------- */
-
-static void** ialloc(mstate m,
- size_t n_elements,
- size_t* sizes,
- int opts,
- void* chunks[]) {
- /*
- This provides common support for independent_X routines, handling
- all of the combinations that can result.
-
- The opts arg has:
- bit 0 set if all elements are same size (using sizes[0])
- bit 1 set if elements should be zeroed
- */
-
- size_t element_size; /* chunksize of each element, if all same */
- size_t contents_size; /* total size of elements */
- size_t array_size; /* request size of pointer array */
- void* mem; /* malloced aggregate space */
- mchunkptr p; /* corresponding chunk */
- size_t remainder_size; /* remaining bytes while splitting */
- void** marray; /* either "chunks" or malloced ptr array */
- mchunkptr array_chunk; /* chunk for malloced ptr array */
- flag_t was_enabled; /* to disable mmap */
- size_t size;
- size_t i;
-
- ensure_initialization();
- /* compute array length, if needed */
- if (chunks != 0) {
- if (n_elements == 0)
- return chunks; /* nothing to do */
- marray = chunks;
- array_size = 0;
- }
- else {
- /* if empty req, must still return chunk representing empty array */
- if (n_elements == 0)
- return (void**)internal_malloc(m, 0);
- marray = 0;
- array_size = request2size(n_elements * (sizeof(void*)));
- }
-
- /* compute total element size */
- if (opts & 0x1) { /* all-same-size */
- element_size = request2size(*sizes);
- contents_size = n_elements * element_size;
- }
- else { /* add up all the sizes */
- element_size = 0;
- contents_size = 0;
- for (i = 0; i != n_elements; ++i)
- contents_size += request2size(sizes[i]);
- }
-
- size = contents_size + array_size;
-
- /*
- Allocate the aggregate chunk. First disable direct-mmapping so
- malloc won't use it, since we would not be able to later
- free/realloc space internal to a segregated mmap region.
- */
- was_enabled = use_mmap(m);
- disable_mmap(m);
- mem = internal_malloc(m, size - CHUNK_OVERHEAD);
- if (was_enabled)
- enable_mmap(m);
- if (mem == 0)
- return 0;
-
- if (PREACTION(m)) return 0;
- p = mem2chunk(mem);
- remainder_size = chunksize(p);
-
- assert(!is_mmapped(p));
-
- if (opts & 0x2) { /* optionally clear the elements */
- memset((size_t*)mem, 0, remainder_size - SIZE_T_SIZE - array_size);
- }
-
- /* If not provided, allocate the pointer array as final part of chunk */
- if (marray == 0) {
- size_t array_chunk_size;
- array_chunk = chunk_plus_offset(p, contents_size);
- array_chunk_size = remainder_size - contents_size;
- marray = (void**) (chunk2mem(array_chunk));
- set_size_and_pinuse_of_inuse_chunk(m, array_chunk, array_chunk_size);
- remainder_size = contents_size;
- }
-
- /* split out elements */
- for (i = 0; ; ++i) {
- marray[i] = chunk2mem(p);
- if (i != n_elements-1) {
- if (element_size != 0)
- size = element_size;
- else
- size = request2size(sizes[i]);
- remainder_size -= size;
- set_size_and_pinuse_of_inuse_chunk(m, p, size);
- p = chunk_plus_offset(p, size);
- }
- else { /* the final element absorbs any overallocation slop */
- set_size_and_pinuse_of_inuse_chunk(m, p, remainder_size);
- break;
- }
- }
-
-#if DEBUG
- if (marray != chunks) {
- /* final element must have exactly exhausted chunk */
- if (element_size != 0) {
- assert(remainder_size == element_size);
- }
- else {
- assert(remainder_size == request2size(sizes[i]));
- }
- check_inuse_chunk(m, mem2chunk(marray));
- }
- for (i = 0; i != n_elements; ++i)
- check_inuse_chunk(m, mem2chunk(marray[i]));
-
-#endif /* DEBUG */
-
- POSTACTION(m);
- return marray;
-}
-
-
-/* -------------------------- public routines ---------------------------- */
-
-#if !ONLY_MSPACES
-
-void* dlmalloc(size_t bytes) {
- /*
- Basic algorithm:
- If a small request (< 256 bytes minus per-chunk overhead):
- 1. If one exists, use a remainderless chunk in associated smallbin.
- (Remainderless means that there are too few excess bytes to
- represent as a chunk.)
- 2. If it is big enough, use the dv chunk, which is normally the
- chunk adjacent to the one used for the most recent small request.
- 3. If one exists, split the smallest available chunk in a bin,
- saving remainder in dv.
- 4. If it is big enough, use the top chunk.
- 5. If available, get memory from system and use it
- Otherwise, for a large request:
- 1. Find the smallest available binned chunk that fits, and use it
- if it is better fitting than dv chunk, splitting if necessary.
- 2. If better fitting than any binned chunk, use the dv chunk.
- 3. If it is big enough, use the top chunk.
- 4. If request size >= mmap threshold, try to directly mmap this chunk.
- 5. If available, get memory from system and use it
-
- The ugly goto's here ensure that postaction occurs along all paths.
- */
-
-#if USE_LOCKS
- ensure_initialization(); /* initialize in sys_alloc if not using locks */
-#endif
-
- if (!PREACTION(gm)) {
- void* mem;
- size_t nb;
- if (bytes <= MAX_SMALL_REQUEST) {
- bindex_t idx;
- binmap_t smallbits;
- nb = (bytes < MIN_REQUEST)? MIN_CHUNK_SIZE : pad_request(bytes);
- idx = small_index(nb);
- smallbits = gm->smallmap >> idx;
-
- if ((smallbits & 0x3U) != 0) { /* Remainderless fit to a smallbin. */
- mchunkptr b, p;
- idx += ~smallbits & 1; /* Uses next bin if idx empty */
- b = smallbin_at(gm, idx);
- p = b->fd;
- assert(chunksize(p) == small_index2size(idx));
- unlink_first_small_chunk(gm, b, p, idx);
- set_inuse_and_pinuse(gm, p, small_index2size(idx));
- mem = chunk2mem(p);
- check_malloced_chunk(gm, mem, nb);
- goto postaction;
- }
-
- else if (nb > gm->dvsize) {
- if (smallbits != 0) { /* Use chunk in next nonempty smallbin */
- mchunkptr b, p, r;
- size_t rsize;
- bindex_t i;
- binmap_t leftbits = (smallbits << idx) & left_bits(idx2bit(idx));
- binmap_t leastbit = least_bit(leftbits);
- compute_bit2idx(leastbit, i);
- b = smallbin_at(gm, i);
- p = b->fd;
- assert(chunksize(p) == small_index2size(i));
- unlink_first_small_chunk(gm, b, p, i);
- rsize = small_index2size(i) - nb;
- /* Fit here cannot be remainderless if 4byte sizes */
- if (SIZE_T_SIZE != 4 && rsize < MIN_CHUNK_SIZE)
- set_inuse_and_pinuse(gm, p, small_index2size(i));
- else {
- set_size_and_pinuse_of_inuse_chunk(gm, p, nb);
- r = chunk_plus_offset(p, nb);
- set_size_and_pinuse_of_free_chunk(r, rsize);
- replace_dv(gm, r, rsize);
- }
- mem = chunk2mem(p);
- check_malloced_chunk(gm, mem, nb);
- goto postaction;
- }
-
- else if (gm->treemap != 0 && (mem = tmalloc_small(gm, nb)) != 0) {
- check_malloced_chunk(gm, mem, nb);
- goto postaction;
- }
- }
- }
- else if (bytes >= MAX_REQUEST)
- nb = MAX_SIZE_T; /* Too big to allocate. Force failure (in sys alloc) */
- else {
- nb = pad_request(bytes);
- if (gm->treemap != 0 && (mem = tmalloc_large(gm, nb)) != 0) {
- check_malloced_chunk(gm, mem, nb);
- goto postaction;
- }
- }
-
- if (nb <= gm->dvsize) {
- size_t rsize = gm->dvsize - nb;
- mchunkptr p = gm->dv;
- if (rsize >= MIN_CHUNK_SIZE) { /* split dv */
- mchunkptr r = gm->dv = chunk_plus_offset(p, nb);
- gm->dvsize = rsize;
- set_size_and_pinuse_of_free_chunk(r, rsize);
- set_size_and_pinuse_of_inuse_chunk(gm, p, nb);
- }
- else { /* exhaust dv */
- size_t dvs = gm->dvsize;
- gm->dvsize = 0;
- gm->dv = 0;
- set_inuse_and_pinuse(gm, p, dvs);
- }
- mem = chunk2mem(p);
- check_malloced_chunk(gm, mem, nb);
- goto postaction;
- }
-
- else if (nb < gm->topsize) { /* Split top */
- size_t rsize = gm->topsize -= nb;
- mchunkptr p = gm->top;
- mchunkptr r = gm->top = chunk_plus_offset(p, nb);
- r->head = rsize | PINUSE_BIT;
- set_size_and_pinuse_of_inuse_chunk(gm, p, nb);
- mem = chunk2mem(p);
- check_top_chunk(gm, gm->top);
- check_malloced_chunk(gm, mem, nb);
- goto postaction;
- }
-
- mem = sys_alloc(gm, nb);
-
- postaction:
- POSTACTION(gm);
- return mem;
- }
-
- return 0;
-}
-
-void dlfree(void* mem) {
- /*
- Consolidate freed chunks with preceding or succeeding bordering
- free chunks, if they exist, and then place in a bin. Intermixed
- with special cases for top, dv, mmapped chunks, and usage errors.
- */
-
- if (mem != 0) {
- mchunkptr p = mem2chunk(mem);
-#if FOOTERS
- mstate fm = get_mstate_for(p);
- if (!ok_magic(fm)) {
- USAGE_ERROR_ACTION(fm, p);
- return;
- }
-#else /* FOOTERS */
-#define fm gm
-#endif /* FOOTERS */
- if (!PREACTION(fm)) {
- check_inuse_chunk(fm, p);
- if (RTCHECK(ok_address(fm, p) && ok_cinuse(p))) {
- size_t psize = chunksize(p);
- mchunkptr next = chunk_plus_offset(p, psize);
- if (!pinuse(p)) {
- size_t prevsize = p->prev_foot;
- if ((prevsize & IS_MMAPPED_BIT) != 0) {
- prevsize &= ~IS_MMAPPED_BIT;
- psize += prevsize + MMAP_FOOT_PAD;
- if (CALL_MUNMAP((char*)p - prevsize, psize) == 0)
- fm->footprint -= psize;
- goto postaction;
- }
- else {
- mchunkptr prev = chunk_minus_offset(p, prevsize);
- psize += prevsize;
- p = prev;
- if (RTCHECK(ok_address(fm, prev))) { /* consolidate backward */
- if (p != fm->dv) {
- unlink_chunk(fm, p, prevsize);
- }
- else if ((next->head & INUSE_BITS) == INUSE_BITS) {
- fm->dvsize = psize;
- set_free_with_pinuse(p, psize, next);
- goto postaction;
- }
- }
- else
- goto erroraction;
- }
- }
-
- if (RTCHECK(ok_next(p, next) && ok_pinuse(next))) {
- if (!cinuse(next)) { /* consolidate forward */
- if (next == fm->top) {
- size_t tsize = fm->topsize += psize;
- fm->top = p;
- p->head = tsize | PINUSE_BIT;
- if (p == fm->dv) {
- fm->dv = 0;
- fm->dvsize = 0;
- }
- if (should_trim(fm, tsize))
- sys_trim(fm, 0);
- goto postaction;
- }
- else if (next == fm->dv) {
- size_t dsize = fm->dvsize += psize;
- fm->dv = p;
- set_size_and_pinuse_of_free_chunk(p, dsize);
- goto postaction;
- }
- else {
- size_t nsize = chunksize(next);
- psize += nsize;
- unlink_chunk(fm, next, nsize);
- set_size_and_pinuse_of_free_chunk(p, psize);
- if (p == fm->dv) {
- fm->dvsize = psize;
- goto postaction;
- }
- }
- }
- else
- set_free_with_pinuse(p, psize, next);
-
- if (is_small(psize)) {
- insert_small_chunk(fm, p, psize);
- check_free_chunk(fm, p);
- }
- else {
- tchunkptr tp = (tchunkptr)p;
- insert_large_chunk(fm, tp, psize);
- check_free_chunk(fm, p);
- if (--fm->release_checks == 0)
- release_unused_segments(fm);
- }
- goto postaction;
- }
- }
- erroraction:
- USAGE_ERROR_ACTION(fm, p);
- postaction:
- POSTACTION(fm);
- }
- }
-#if !FOOTERS
-#undef fm
-#endif /* FOOTERS */
-}
-
-void* dlcalloc(size_t n_elements, size_t elem_size) {
- void* mem;
- size_t req = 0;
- if (n_elements != 0) {
- req = n_elements * elem_size;
- if (((n_elements | elem_size) & ~(size_t)0xffff) &&
- (req / n_elements != elem_size))
- req = MAX_SIZE_T; /* force downstream failure on overflow */
- }
- mem = dlmalloc(req);
- if (mem != 0 && calloc_must_clear(mem2chunk(mem)))
- memset(mem, 0, req);
- return mem;
-}
-
-void* dlrealloc(void* oldmem, size_t bytes) {
- if (oldmem == 0)
- return dlmalloc(bytes);
-#ifdef REALLOC_ZERO_BYTES_FREES
- if (bytes == 0) {
- dlfree(oldmem);
- return 0;
- }
-#endif /* REALLOC_ZERO_BYTES_FREES */
- else {
-#if ! FOOTERS
- mstate m = gm;
-#else /* FOOTERS */
- mstate m = get_mstate_for(mem2chunk(oldmem));
- if (!ok_magic(m)) {
- USAGE_ERROR_ACTION(m, oldmem);
- return 0;
- }
-#endif /* FOOTERS */
- return internal_realloc(m, oldmem, bytes);
- }
-}
-
-void* dlmemalign(size_t alignment, size_t bytes) {
- return internal_memalign(gm, alignment, bytes);
-}
-
-void** dlindependent_calloc(size_t n_elements, size_t elem_size,
- void* chunks[]) {
- size_t sz = elem_size; /* serves as 1-element array */
- return ialloc(gm, n_elements, &sz, 3, chunks);
-}
-
-void** dlindependent_comalloc(size_t n_elements, size_t sizes[],
- void* chunks[]) {
- return ialloc(gm, n_elements, sizes, 0, chunks);
-}
-
-void* dlvalloc(size_t bytes) {
- size_t pagesz;
- ensure_initialization();
- pagesz = mparams.page_size;
- return dlmemalign(pagesz, bytes);
-}
-
-void* dlpvalloc(size_t bytes) {
- size_t pagesz;
- ensure_initialization();
- pagesz = mparams.page_size;
- return dlmemalign(pagesz, (bytes + pagesz - SIZE_T_ONE) & ~(pagesz - SIZE_T_ONE));
-}
-
-int dlmalloc_trim(size_t pad) {
- ensure_initialization();
- int result = 0;
- if (!PREACTION(gm)) {
- result = sys_trim(gm, pad);
- POSTACTION(gm);
- }
- return result;
-}
-
-size_t dlmalloc_footprint(void) {
- return gm->footprint;
-}
-
-size_t dlmalloc_max_footprint(void) {
- return gm->max_footprint;
-}
-
-#if !NO_MALLINFO
-struct mallinfo dlmallinfo(void) {
- return internal_mallinfo(gm);
-}
-#endif /* NO_MALLINFO */
-
-void dlmalloc_stats() {
- internal_malloc_stats(gm);
-}
-
-int dlmallopt(int param_number, int value) {
- return change_mparam(param_number, value);
-}
-
-#endif /* !ONLY_MSPACES */
-
-size_t dlmalloc_usable_size(void* mem) {
- if (mem != 0) {
- mchunkptr p = mem2chunk(mem);
- if (cinuse(p))
- return chunksize(p) - overhead_for(p);
- }
- return 0;
-}
-
-/* ----------------------------- user mspaces ---------------------------- */
-
-#if MSPACES
-
-static mstate init_user_mstate(char* tbase, size_t tsize) {
- size_t msize = pad_request(sizeof(struct malloc_state));
- mchunkptr mn;
- mchunkptr msp = align_as_chunk(tbase);
- mstate m = (mstate)(chunk2mem(msp));
- memset(m, 0, msize);
- (void)INITIAL_LOCK(&m->mutex);
- msp->head = (msize|PINUSE_BIT|CINUSE_BIT);
- m->seg.base = m->least_addr = tbase;
- m->seg.size = m->footprint = m->max_footprint = tsize;
- m->magic = mparams.magic;
- m->release_checks = MAX_RELEASE_CHECK_RATE;
- m->mflags = mparams.default_mflags;
- m->extp = 0;
- m->exts = 0;
- disable_contiguous(m);
- init_bins(m);
- mn = next_chunk(mem2chunk(m));
- init_top(m, mn, (size_t)((tbase + tsize) - (char*)mn) - TOP_FOOT_SIZE);
- check_top_chunk(m, m->top);
- return m;
-}
-
-mspace create_mspace(size_t capacity, int locked) {
- mstate m = 0;
- size_t msize;
- ensure_initialization();
- msize = pad_request(sizeof(struct malloc_state));
- if (capacity < (size_t) -(msize + TOP_FOOT_SIZE + mparams.page_size)) {
- size_t rs = ((capacity == 0)? mparams.granularity :
- (capacity + TOP_FOOT_SIZE + msize));
- size_t tsize = granularity_align(rs);
- char* tbase = (char*)(CALL_MMAP(tsize));
- if (tbase != CMFAIL) {
- m = init_user_mstate(tbase, tsize);
- m->seg.sflags = IS_MMAPPED_BIT;
- set_lock(m, locked);
- }
- }
- return (mspace)m;
-}
-
-mspace create_mspace_with_base(void* base, size_t capacity, int locked) {
- mstate m = 0;
- size_t msize;
- ensure_initialization();
- msize = pad_request(sizeof(struct malloc_state));
- if (capacity > msize + TOP_FOOT_SIZE &&
- capacity < (size_t) -(msize + TOP_FOOT_SIZE + mparams.page_size)) {
- m = init_user_mstate((char*)base, capacity);
- m->seg.sflags = EXTERN_BIT;
- set_lock(m, locked);
- }
- return (mspace)m;
-}
-
-int mspace_mmap_large_chunks(mspace msp, int enable) {
- int ret = 0;
- mstate ms = (mstate)msp;
- if (!PREACTION(ms)) {
- if (use_mmap(ms))
- ret = 1;
- if (enable)
- enable_mmap(ms);
- else
- disable_mmap(ms);
- POSTACTION(ms);
- }
- return ret;
-}
-
-size_t destroy_mspace(mspace msp) {
- size_t freed = 0;
- mstate ms = (mstate)msp;
- if (ok_magic(ms)) {
- msegmentptr sp = &ms->seg;
- while (sp != 0) {
- char* base = sp->base;
- size_t size = sp->size;
- flag_t flag = sp->sflags;
- sp = sp->next;
- if ((flag & IS_MMAPPED_BIT) && !(flag & EXTERN_BIT) &&
- CALL_MUNMAP(base, size) == 0)
- freed += size;
- }
- }
- else {
- USAGE_ERROR_ACTION(ms,ms);
- }
- return freed;
-}
-
-/*
- mspace versions of routines are near-clones of the global
- versions. This is not so nice but better than the alternatives.
-*/
-
-
-void* mspace_malloc(mspace msp, size_t bytes) {
- mstate ms = (mstate)msp;
- if (!ok_magic(ms)) {
- USAGE_ERROR_ACTION(ms,ms);
- return 0;
- }
- if (!PREACTION(ms)) {
- void* mem;
- size_t nb;
- if (bytes <= MAX_SMALL_REQUEST) {
- bindex_t idx;
- binmap_t smallbits;
- nb = (bytes < MIN_REQUEST)? MIN_CHUNK_SIZE : pad_request(bytes);
- idx = small_index(nb);
- smallbits = ms->smallmap >> idx;
-
- if ((smallbits & 0x3U) != 0) { /* Remainderless fit to a smallbin. */
- mchunkptr b, p;
- idx += ~smallbits & 1; /* Uses next bin if idx empty */
- b = smallbin_at(ms, idx);
- p = b->fd;
- assert(chunksize(p) == small_index2size(idx));
- unlink_first_small_chunk(ms, b, p, idx);
- set_inuse_and_pinuse(ms, p, small_index2size(idx));
- mem = chunk2mem(p);
- check_malloced_chunk(ms, mem, nb);
- goto postaction;
- }
-
- else if (nb > ms->dvsize) {
- if (smallbits != 0) { /* Use chunk in next nonempty smallbin */
- mchunkptr b, p, r;
- size_t rsize;
- bindex_t i;
- binmap_t leftbits = (smallbits << idx) & left_bits(idx2bit(idx));
- binmap_t leastbit = least_bit(leftbits);
- compute_bit2idx(leastbit, i);
- b = smallbin_at(ms, i);
- p = b->fd;
- assert(chunksize(p) == small_index2size(i));
- unlink_first_small_chunk(ms, b, p, i);
- rsize = small_index2size(i) - nb;
- /* Fit here cannot be remainderless if 4byte sizes */
- if (SIZE_T_SIZE != 4 && rsize < MIN_CHUNK_SIZE)
- set_inuse_and_pinuse(ms, p, small_index2size(i));
- else {
- set_size_and_pinuse_of_inuse_chunk(ms, p, nb);
- r = chunk_plus_offset(p, nb);
- set_size_and_pinuse_of_free_chunk(r, rsize);
- replace_dv(ms, r, rsize);
- }
- mem = chunk2mem(p);
- check_malloced_chunk(ms, mem, nb);
- goto postaction;
- }
-
- else if (ms->treemap != 0 && (mem = tmalloc_small(ms, nb)) != 0) {
- check_malloced_chunk(ms, mem, nb);
- goto postaction;
- }
- }
- }
- else if (bytes >= MAX_REQUEST)
- nb = MAX_SIZE_T; /* Too big to allocate. Force failure (in sys alloc) */
- else {
- nb = pad_request(bytes);
- if (ms->treemap != 0 && (mem = tmalloc_large(ms, nb)) != 0) {
- check_malloced_chunk(ms, mem, nb);
- goto postaction;
- }
- }
-
- if (nb <= ms->dvsize) {
- size_t rsize = ms->dvsize - nb;
- mchunkptr p = ms->dv;
- if (rsize >= MIN_CHUNK_SIZE) { /* split dv */
- mchunkptr r = ms->dv = chunk_plus_offset(p, nb);
- ms->dvsize = rsize;
- set_size_and_pinuse_of_free_chunk(r, rsize);
- set_size_and_pinuse_of_inuse_chunk(ms, p, nb);
- }
- else { /* exhaust dv */
- size_t dvs = ms->dvsize;
- ms->dvsize = 0;
- ms->dv = 0;
- set_inuse_and_pinuse(ms, p, dvs);
- }
- mem = chunk2mem(p);
- check_malloced_chunk(ms, mem, nb);
- goto postaction;
- }
-
- else if (nb < ms->topsize) { /* Split top */
- size_t rsize = ms->topsize -= nb;
- mchunkptr p = ms->top;
- mchunkptr r = ms->top = chunk_plus_offset(p, nb);
- r->head = rsize | PINUSE_BIT;
- set_size_and_pinuse_of_inuse_chunk(ms, p, nb);
- mem = chunk2mem(p);
- check_top_chunk(ms, ms->top);
- check_malloced_chunk(ms, mem, nb);
- goto postaction;
- }
-
- mem = sys_alloc(ms, nb);
-
- postaction:
- POSTACTION(ms);
- return mem;
- }
-
- return 0;
-}
-
-void mspace_free(mspace msp, void* mem) {
- if (mem != 0) {
- mchunkptr p = mem2chunk(mem);
-#if FOOTERS
- mstate fm = get_mstate_for(p);
-#else /* FOOTERS */
- mstate fm = (mstate)msp;
-#endif /* FOOTERS */
- if (!ok_magic(fm)) {
- USAGE_ERROR_ACTION(fm, p);
- return;
- }
- if (!PREACTION(fm)) {
- check_inuse_chunk(fm, p);
- if (RTCHECK(ok_address(fm, p) && ok_cinuse(p))) {
- size_t psize = chunksize(p);
- mchunkptr next = chunk_plus_offset(p, psize);
- if (!pinuse(p)) {
- size_t prevsize = p->prev_foot;
- if ((prevsize & IS_MMAPPED_BIT) != 0) {
- prevsize &= ~IS_MMAPPED_BIT;
- psize += prevsize + MMAP_FOOT_PAD;
- if (CALL_MUNMAP((char*)p - prevsize, psize) == 0)
- fm->footprint -= psize;
- goto postaction;
- }
- else {
- mchunkptr prev = chunk_minus_offset(p, prevsize);
- psize += prevsize;
- p = prev;
- if (RTCHECK(ok_address(fm, prev))) { /* consolidate backward */
- if (p != fm->dv) {
- unlink_chunk(fm, p, prevsize);
- }
- else if ((next->head & INUSE_BITS) == INUSE_BITS) {
- fm->dvsize = psize;
- set_free_with_pinuse(p, psize, next);
- goto postaction;
- }
- }
- else
- goto erroraction;
- }
- }
-
- if (RTCHECK(ok_next(p, next) && ok_pinuse(next))) {
- if (!cinuse(next)) { /* consolidate forward */
- if (next == fm->top) {
- size_t tsize = fm->topsize += psize;
- fm->top = p;
- p->head = tsize | PINUSE_BIT;
- if (p == fm->dv) {
- fm->dv = 0;
- fm->dvsize = 0;
- }
- if (should_trim(fm, tsize))
- sys_trim(fm, 0);
- goto postaction;
- }
- else if (next == fm->dv) {
- size_t dsize = fm->dvsize += psize;
- fm->dv = p;
- set_size_and_pinuse_of_free_chunk(p, dsize);
- goto postaction;
- }
- else {
- size_t nsize = chunksize(next);
- psize += nsize;
- unlink_chunk(fm, next, nsize);
- set_size_and_pinuse_of_free_chunk(p, psize);
- if (p == fm->dv) {
- fm->dvsize = psize;
- goto postaction;
- }
- }
- }
- else
- set_free_with_pinuse(p, psize, next);
-
- if (is_small(psize)) {
- insert_small_chunk(fm, p, psize);
- check_free_chunk(fm, p);
- }
- else {
- tchunkptr tp = (tchunkptr)p;
- insert_large_chunk(fm, tp, psize);
- check_free_chunk(fm, p);
- if (--fm->release_checks == 0)
- release_unused_segments(fm);
- }
- goto postaction;
- }
- }
- erroraction:
- USAGE_ERROR_ACTION(fm, p);
- postaction:
- POSTACTION(fm);
- }
- }
-}
-
-void* mspace_calloc(mspace msp, size_t n_elements, size_t elem_size) {
- void* mem;
- size_t req = 0;
- mstate ms = (mstate)msp;
- if (!ok_magic(ms)) {
- USAGE_ERROR_ACTION(ms,ms);
- return 0;
- }
- if (n_elements != 0) {
- req = n_elements * elem_size;
- if (((n_elements | elem_size) & ~(size_t)0xffff) &&
- (req / n_elements != elem_size))
- req = MAX_SIZE_T; /* force downstream failure on overflow */
- }
- mem = internal_malloc(ms, req);
- if (mem != 0 && calloc_must_clear(mem2chunk(mem)))
- memset(mem, 0, req);
- return mem;
-}
-
-void* mspace_realloc(mspace msp, void* oldmem, size_t bytes) {
- if (oldmem == 0)
- return mspace_malloc(msp, bytes);
-#ifdef REALLOC_ZERO_BYTES_FREES
- if (bytes == 0) {
- mspace_free(msp, oldmem);
- return 0;
- }
-#endif /* REALLOC_ZERO_BYTES_FREES */
- else {
-#if FOOTERS
- mchunkptr p = mem2chunk(oldmem);
- mstate ms = get_mstate_for(p);
-#else /* FOOTERS */
- mstate ms = (mstate)msp;
-#endif /* FOOTERS */
- if (!ok_magic(ms)) {
- USAGE_ERROR_ACTION(ms,ms);
- return 0;
- }
- return internal_realloc(ms, oldmem, bytes);
- }
-}
-
-void* mspace_memalign(mspace msp, size_t alignment, size_t bytes) {
- mstate ms = (mstate)msp;
- if (!ok_magic(ms)) {
- USAGE_ERROR_ACTION(ms,ms);
- return 0;
- }
- return internal_memalign(ms, alignment, bytes);
-}
-
-void** mspace_independent_calloc(mspace msp, size_t n_elements,
- size_t elem_size, void* chunks[]) {
- size_t sz = elem_size; /* serves as 1-element array */
- mstate ms = (mstate)msp;
- if (!ok_magic(ms)) {
- USAGE_ERROR_ACTION(ms,ms);
- return 0;
- }
- return ialloc(ms, n_elements, &sz, 3, chunks);
-}
-
-void** mspace_independent_comalloc(mspace msp, size_t n_elements,
- size_t sizes[], void* chunks[]) {
- mstate ms = (mstate)msp;
- if (!ok_magic(ms)) {
- USAGE_ERROR_ACTION(ms,ms);
- return 0;
- }
- return ialloc(ms, n_elements, sizes, 0, chunks);
-}
-
-int mspace_trim(mspace msp, size_t pad) {
- int result = 0;
- mstate ms = (mstate)msp;
- if (ok_magic(ms)) {
- if (!PREACTION(ms)) {
- result = sys_trim(ms, pad);
- POSTACTION(ms);
- }
- }
- else {
- USAGE_ERROR_ACTION(ms,ms);
- }
- return result;
-}
-
-void mspace_malloc_stats(mspace msp) {
- mstate ms = (mstate)msp;
- if (ok_magic(ms)) {
- internal_malloc_stats(ms);
- }
- else {
- USAGE_ERROR_ACTION(ms,ms);
- }
-}
-
-size_t mspace_footprint(mspace msp) {
- size_t result = 0;
- mstate ms = (mstate)msp;
- if (ok_magic(ms)) {
- result = ms->footprint;
- }
- else {
- USAGE_ERROR_ACTION(ms,ms);
- }
- return result;
-}
-
-
-size_t mspace_max_footprint(mspace msp) {
- size_t result = 0;
- mstate ms = (mstate)msp;
- if (ok_magic(ms)) {
- result = ms->max_footprint;
- }
- else {
- USAGE_ERROR_ACTION(ms,ms);
- }
- return result;
-}
-
-
-#if !NO_MALLINFO
-struct mallinfo mspace_mallinfo(mspace msp) {
- mstate ms = (mstate)msp;
- if (!ok_magic(ms)) {
- USAGE_ERROR_ACTION(ms,ms);
- }
- return internal_mallinfo(ms);
-}
-#endif /* NO_MALLINFO */
-
-size_t mspace_usable_size(void* mem) {
- if (mem != 0) {
- mchunkptr p = mem2chunk(mem);
- if (cinuse(p))
- return chunksize(p) - overhead_for(p);
- }
- return 0;
-}
-
-int mspace_mallopt(int param_number, int value) {
- return change_mparam(param_number, value);
-}
-
-#endif /* MSPACES */
-
-/* -------------------- Alternative MORECORE functions ------------------- */
-
-/*
- Guidelines for creating a custom version of MORECORE:
-
- * For best performance, MORECORE should allocate in multiples of pagesize.
- * MORECORE may allocate more memory than requested. (Or even less,
- but this will usually result in a malloc failure.)
- * MORECORE must not allocate memory when given argument zero, but
- instead return one past the end address of memory from previous
- nonzero call.
- * For best performance, consecutive calls to MORECORE with positive
- arguments should return increasing addresses, indicating that
- space has been contiguously extended.
- * Even though consecutive calls to MORECORE need not return contiguous
- addresses, it must be OK for malloc'ed chunks to span multiple
- regions in those cases where they do happen to be contiguous.
- * MORECORE need not handle negative arguments -- it may instead
- just return MFAIL when given negative arguments.
- Negative arguments are always multiples of pagesize. MORECORE
- must not misinterpret negative args as large positive unsigned
- args. You can suppress all such calls from even occurring by defining
- MORECORE_CANNOT_TRIM,
-
- As an example alternative MORECORE, here is a custom allocator
- kindly contributed for pre-OSX macOS. It uses virtually but not
- necessarily physically contiguous non-paged memory (locked in,
- present and won't get swapped out). You can use it by uncommenting
- this section, adding some #includes, and setting up the appropriate
- defines above:
-
- #define MORECORE osMoreCore
-
- There is also a shutdown routine that should somehow be called for
- cleanup upon program exit.
-
- #define MAX_POOL_ENTRIES 100
- #define MINIMUM_MORECORE_SIZE (64 * 1024U)
- static int next_os_pool;
- void *our_os_pools[MAX_POOL_ENTRIES];
-
- void *osMoreCore(int size)
- {
- void *ptr = 0;
- static void *sbrk_top = 0;
-
- if (size > 0)
- {
- if (size < MINIMUM_MORECORE_SIZE)
- size = MINIMUM_MORECORE_SIZE;
- if (CurrentExecutionLevel() == kTaskLevel)
- ptr = PoolAllocateResident(size + RM_PAGE_SIZE, 0);
- if (ptr == 0)
- {
- return (void *) MFAIL;
- }
- // save ptrs so they can be freed during cleanup
- our_os_pools[next_os_pool] = ptr;
- next_os_pool++;
- ptr = (void *) ((((size_t) ptr) + RM_PAGE_MASK) & ~RM_PAGE_MASK);
- sbrk_top = (char *) ptr + size;
- return ptr;
- }
- else if (size < 0)
- {
- // we don't currently support shrink behavior
- return (void *) MFAIL;
- }
- else
- {
- return sbrk_top;
- }
- }
-
- // cleanup any allocated memory pools
- // called as last thing before shutting down driver
-
- void osCleanupMem(void)
- {
- void **ptr;
-
- for (ptr = our_os_pools; ptr < &our_os_pools[MAX_POOL_ENTRIES]; ptr++)
- if (*ptr)
- {
- PoolDeallocate(*ptr);
- *ptr = 0;
- }
- }
-
-*/
-
-
-/* -----------------------------------------------------------------------
-History:
- V2.8.4 (not yet released)
- * Add mspace_mmap_large_chunks; thanks to Jean Brouwers
- * Fix insufficient sys_alloc padding when using 16byte alignment
- * Fix bad error check in mspace_footprint
- * Adaptations for ptmalloc, courtesy of Wolfram Gloger.
- * Reentrant spin locks, courtesy of Earl Chew and others
- * Win32 improvements, courtesy of Niall Douglas and Earl Chew
- * Add NO_SEGMENT_TRAVERSAL and MAX_RELEASE_CHECK_RATE options
- * Extension hook in malloc_state
- * Various small adjustments to reduce warnings on some compilers
- * Various configuration extensions/changes for more platforms. Thanks
- to all who contributed these.
-
- V2.8.3 Thu Sep 22 11:16:32 2005 Doug Lea (dl at gee)
- * Add max_footprint functions
- * Ensure all appropriate literals are size_t
- * Fix conditional compilation problem for some #define settings
- * Avoid concatenating segments with the one provided
- in create_mspace_with_base
- * Rename some variables to avoid compiler shadowing warnings
- * Use explicit lock initialization.
- * Better handling of sbrk interference.
- * Simplify and fix segment insertion, trimming and mspace_destroy
- * Reinstate REALLOC_ZERO_BYTES_FREES option from 2.7.x
- * Thanks especially to Dennis Flanagan for help on these.
-
- V2.8.2 Sun Jun 12 16:01:10 2005 Doug Lea (dl at gee)
- * Fix memalign brace error.
-
- V2.8.1 Wed Jun 8 16:11:46 2005 Doug Lea (dl at gee)
- * Fix improper #endif nesting in C++
- * Add explicit casts needed for C++
-
- V2.8.0 Mon May 30 14:09:02 2005 Doug Lea (dl at gee)
- * Use trees for large bins
- * Support mspaces
- * Use segments to unify sbrk-based and mmap-based system allocation,
- removing need for emulation on most platforms without sbrk.
- * Default safety checks
- * Optional footer checks. Thanks to William Robertson for the idea.
- * Internal code refactoring
- * Incorporate suggestions and platform-specific changes.
- Thanks to Dennis Flanagan, Colin Plumb, Niall Douglas,
- Aaron Bachmann, Emery Berger, and others.
- * Speed up non-fastbin processing enough to remove fastbins.
- * Remove useless cfree() to avoid conflicts with other apps.
- * Remove internal memcpy, memset. Compilers handle builtins better.
- * Remove some options that no one ever used and rename others.
-
- V2.7.2 Sat Aug 17 09:07:30 2002 Doug Lea (dl at gee)
- * Fix malloc_state bitmap array misdeclaration
-
- V2.7.1 Thu Jul 25 10:58:03 2002 Doug Lea (dl at gee)
- * Allow tuning of FIRST_SORTED_BIN_SIZE
- * Use PTR_UINT as type for all ptr->int casts. Thanks to John Belmonte.
- * Better detection and support for non-contiguousness of MORECORE.
- Thanks to Andreas Mueller, Conal Walsh, and Wolfram Gloger
- * Bypass most of malloc if no frees. Thanks To Emery Berger.
- * Fix freeing of old top non-contiguous chunk im sysmalloc.
- * Raised default trim and map thresholds to 256K.
- * Fix mmap-related #defines. Thanks to Lubos Lunak.
- * Fix copy macros; added LACKS_FCNTL_H. Thanks to Neal Walfield.
- * Branch-free bin calculation
- * Default trim and mmap thresholds now 256K.
-
- V2.7.0 Sun Mar 11 14:14:06 2001 Doug Lea (dl at gee)
- * Introduce independent_comalloc and independent_calloc.
- Thanks to Michael Pachos for motivation and help.
- * Make optional .h file available
- * Allow > 2GB requests on 32bit systems.
- * new WIN32 sbrk, mmap, munmap, lock code from <Walter@GeNeSys-e.de>.
- Thanks also to Andreas Mueller <a.mueller at paradatec.de>,
- and Anonymous.
- * Allow override of MALLOC_ALIGNMENT (Thanks to Ruud Waij for
- helping test this.)
- * memalign: check alignment arg
- * realloc: don't try to shift chunks backwards, since this
- leads to more fragmentation in some programs and doesn't
- seem to help in any others.
- * Collect all cases in malloc requiring system memory into sysmalloc
- * Use mmap as backup to sbrk
- * Place all internal state in malloc_state
- * Introduce fastbins (although similar to 2.5.1)
- * Many minor tunings and cosmetic improvements
- * Introduce USE_PUBLIC_MALLOC_WRAPPERS, USE_MALLOC_LOCK
- * Introduce MALLOC_FAILURE_ACTION, MORECORE_CONTIGUOUS
- Thanks to Tony E. Bennett <tbennett@nvidia.com> and others.
- * Include errno.h to support default failure action.
-
- V2.6.6 Sun Dec 5 07:42:19 1999 Doug Lea (dl at gee)
- * return null for negative arguments
- * Added Several WIN32 cleanups from Martin C. Fong <mcfong at yahoo.com>
- * Add 'LACKS_SYS_PARAM_H' for those systems without 'sys/param.h'
- (e.g. WIN32 platforms)
- * Cleanup header file inclusion for WIN32 platforms
- * Cleanup code to avoid Microsoft Visual C++ compiler complaints
- * Add 'USE_DL_PREFIX' to quickly allow co-existence with existing
- memory allocation routines
- * Set 'malloc_getpagesize' for WIN32 platforms (needs more work)
- * Use 'assert' rather than 'ASSERT' in WIN32 code to conform to
- usage of 'assert' in non-WIN32 code
- * Improve WIN32 'sbrk()' emulation's 'findRegion()' routine to
- avoid infinite loop
- * Always call 'fREe()' rather than 'free()'
-
- V2.6.5 Wed Jun 17 15:57:31 1998 Doug Lea (dl at gee)
- * Fixed ordering problem with boundary-stamping
-
- V2.6.3 Sun May 19 08:17:58 1996 Doug Lea (dl at gee)
- * Added pvalloc, as recommended by H.J. Liu
- * Added 64bit pointer support mainly from Wolfram Gloger
- * Added anonymously donated WIN32 sbrk emulation
- * Malloc, calloc, getpagesize: add optimizations from Raymond Nijssen
- * malloc_extend_top: fix mask error that caused wastage after
- foreign sbrks
- * Add linux mremap support code from HJ Liu
-
- V2.6.2 Tue Dec 5 06:52:55 1995 Doug Lea (dl at gee)
- * Integrated most documentation with the code.
- * Add support for mmap, with help from
- Wolfram Gloger (Gloger@lrz.uni-muenchen.de).
- * Use last_remainder in more cases.
- * Pack bins using idea from colin@nyx10.cs.du.edu
- * Use ordered bins instead of best-fit threshold
- * Eliminate block-local decls to simplify tracing and debugging.
- * Support another case of realloc via move into top
- * Fix error occurring when initial sbrk_base not word-aligned.
- * Rely on page size for units instead of SBRK_UNIT to
- avoid surprises about sbrk alignment conventions.
- * Add mallinfo, mallopt. Thanks to Raymond Nijssen
- (raymond@es.ele.tue.nl) for the suggestion.
- * Add `pad' argument to malloc_trim and top_pad mallopt parameter.
- * More precautions for cases where other routines call sbrk,
- courtesy of Wolfram Gloger (Gloger@lrz.uni-muenchen.de).
- * Added macros etc., allowing use in linux libc from
- H.J. Lu (hjl@gnu.ai.mit.edu)
- * Inverted this history list
-
- V2.6.1 Sat Dec 2 14:10:57 1995 Doug Lea (dl at gee)
- * Re-tuned and fixed to behave more nicely with V2.6.0 changes.
- * Removed all preallocation code since under current scheme
- the work required to undo bad preallocations exceeds
- the work saved in good cases for most test programs.
- * No longer use return list or unconsolidated bins since
- no scheme using them consistently outperforms those that don't
- given above changes.
- * Use best fit for very large chunks to prevent some worst-cases.
- * Added some support for debugging
-
- V2.6.0 Sat Nov 4 07:05:23 1995 Doug Lea (dl at gee)
- * Removed footers when chunks are in use. Thanks to
- Paul Wilson (wilson@cs.texas.edu) for the suggestion.
-
- V2.5.4 Wed Nov 1 07:54:51 1995 Doug Lea (dl at gee)
- * Added malloc_trim, with help from Wolfram Gloger
- (wmglo@Dent.MED.Uni-Muenchen.DE).
-
- V2.5.3 Tue Apr 26 10:16:01 1994 Doug Lea (dl at g)
-
- V2.5.2 Tue Apr 5 16:20:40 1994 Doug Lea (dl at g)
- * realloc: try to expand in both directions
- * malloc: swap order of clean-bin strategy;
- * realloc: only conditionally expand backwards
- * Try not to scavenge used bins
- * Use bin counts as a guide to preallocation
- * Occasionally bin return list chunks in first scan
- * Add a few optimizations from colin@nyx10.cs.du.edu
-
- V2.5.1 Sat Aug 14 15:40:43 1993 Doug Lea (dl at g)
- * faster bin computation & slightly different binning
- * merged all consolidations to one part of malloc proper
- (eliminating old malloc_find_space & malloc_clean_bin)
- * Scan 2 returns chunks (not just 1)
- * Propagate failure in realloc if malloc returns 0
- * Add stuff to allow compilation on non-ANSI compilers
- from kpv@research.att.com
-
- V2.5 Sat Aug 7 07:41:59 1993 Doug Lea (dl at g.oswego.edu)
- * removed potential for odd address access in prev_chunk
- * removed dependency on getpagesize.h
- * misc cosmetics and a bit more internal documentation
- * anticosmetics: mangled names in macros to evade debugger strangeness
- * tested on sparc, hp-700, dec-mips, rs6000
- with gcc & native cc (hp, dec only) allowing
- Detlefs & Zorn comparison study (in SIGPLAN Notices.)
-
- Trial version Fri Aug 28 13:14:29 1992 Doug Lea (dl at g.oswego.edu)
- * Based loosely on libg++-1.2X malloc. (It retains some of the overall
- structure of old version, but most details differ.)
-
-*/
--
gitgitgadget
^ permalink raw reply related
* Re: [PATCH v16 0/5] checkout: 'autostash' for branch switching
From: Phillip Wood @ 2026-05-08 13:02 UTC (permalink / raw)
To: Harald Nordgren, gitgitgadget; +Cc: chris.torek, git, peff
In-Reply-To: <20260507201112.41110-1-haraldnordgren@gmail.com>
Hi Harald
On 07/05/2026 21:11, Harald Nordgren wrote:
> Is this ready to be merged?
You can see the current status by reading the latest what's cooking
email from Junio. I don't think he's officially back online until next
week so I wouldn't be surprised if this hasn't been merged yet. You can
always check
git log --merges --grep hn/ origin/next
to see which of your topics are in next.
Thanks
Phillip
^ permalink raw reply
* Re: [PATCH v6] checkout: extend --track with a "fetch" mode to refresh start-point
From: Phillip Wood @ 2026-05-08 13:15 UTC (permalink / raw)
To: Harald Nordgren, gitgitgadget
Cc: ben.knoble, git, kristofferhaugsbakk, marcnarc, ramsay
In-Reply-To: <20260507201253.41428-1-haraldnordgren@gmail.com>
Hi Harald
On 07/05/2026 21:12, Harald Nordgren wrote:
> Is this ready to move to next?
I'm not particularly enthusiastic one way or the other about adding
this, but so long as we only try to fetch when the user explicitly asks
for it I don't particularly object. However having had a quick scan of
the implementation I have a few comments
* "--track=inherit,direct" is nonsense and should be rejected
* currently "--track" has "last one wins" behavior so
"--track=inherit --track=direct" behaves like "--track=direct". We
should probably keep that so that "--track=fetch --track=direct"
behaves like "--track=direct", not "--track=fetch,direct"
* if "git fetch" fails and the remote tracking ref already exists then
we should print a warning and carry on rather than dying which is more
convenient if the user or remote server are offline.
* "git checkout --track=fetch origin/branch" should respect
remote.origin.fetch so that we fetch the ref that we're going to
checkout. I wonder if we can share this logic with the code that
sets the upstream branch.
* "git checkout --track=fetch origin" should only fetch the remote
ref that we're going to checkout, not all the refs from origin. i.e.
it should read origin/HEAD to work out what to fetch.
Thanks
Phillip
^ permalink raw reply
* Re: [PATCH v3 0/6] mingw: stop using nedmalloc
From: Patrick Steinhardt @ 2026-05-08 13:17 UTC (permalink / raw)
To: Johannes Schindelin via GitGitGadget; +Cc: git, Johannes Schindelin
In-Reply-To: <pull.2104.v3.git.1778244661.gitgitgadget@gmail.com>
On Fri, May 08, 2026 at 12:50:55PM +0000, Johannes Schindelin via GitGitGadget wrote:
> Git for Windows' SDK wants to update GCC to v16. Since it is used in the CI
> builds also of the git/git repository, it is crucial that GCC can compile
> even the latter all right, but currently it does not, see
> https://github.com/git-for-windows/git-sdk-64/actions/runs/25244795074.
>
> Git for Windows switched away from nedmalloc to mimalloc a long time ago,
> but recent benchmarks across Windows, macOS, and Linux (see
> https://github.com/git-for-windows/git/pull/6231) show no measurable benefit
> from mimalloc over the platforms' default allocators, so rather than
> upstreaming the mimalloc support, I will drop it from Git for Windows
> entirely.
>
> This series therefore disables nedmalloc for MINGW builds and removes the
> vendored-in nedmalloc from Git's source code; my earlier sketch in
> https://lore.kernel.org/git/00fd3145-b3d2-ddab-466d-d06fd27298ec@gmx.de/ had
> the opposite ordering only because it assumed mimalloc would land first.
> Since that's not going to happen, it's best to move forward with this, so
> that the CI builds can switch to using GCC 16 (and the current Git for
> Windows SDK) on Windows.
>
> The patches that remove the vendored sources have a slightly unusual shape:
> the Git mailing list rejects messages over 100kB and
> compat/nedmalloc/malloc.c.h alone is ~196kB of source, so the deletion of
> that file is split at section boundaries into three commits, each
> comfortably under the cap. The intention (as documented by the last three
> commit messages) is for them to be squashed by the Git maintainer before
> merging.
>
> Changes since v2:
>
> * Reworded the last 4 patches as recommended by Junio, in preparation for
> squashing them on his end.
Heh, fun.
> Changes since v1:
>
> * Also remove nedmalloc from the CMake and Meson configurations in the
> first patch.
> * Add follow-up patches that drop the nedmalloc build-system plumbing and
> source files.
I think removing nedmalloc makes sense, and am happy with the state of
this series. Thanks!
Patrick
^ permalink raw reply
* Re: [PATCH v2 0/2] maintenance(geometric): avoid deadlocks on Windows 10
From: Patrick Steinhardt @ 2026-05-08 13:20 UTC (permalink / raw)
To: Johannes Schindelin via GitGitGadget
Cc: git, Derrick Stolee, Johannes Schindelin
In-Reply-To: <pull.2103.v2.git.1778158273.gitgitgadget@gmail.com>
On Thu, May 07, 2026 at 12:51:11PM +0000, Johannes Schindelin via GitGitGadget wrote:
> On Windows, maintenance_task_geometric_repack() opens pack index files via
> pack_geometry_init() (which mmap()s the .idx files), then spawns git repack
> as a child process without setting child.odb_to_close. The parent's mmap()s
> prevent the child from deleting old .idx files.
>
> On Windows 10 builds before the POSIX delete semantics change (between Build
> 17134.1304 and 18363.657, see https://stackoverflow.com/a/60512798), this
> results in Unlink of file '.git/objects/pack/pack-<hash>.idx' failed. Should
> I try again? during fetch-triggered auto-maintenance with the geometric
> strategy.
>
> The fix adds the missing child.odb_to_close = the_repository->objects line,
> matching all other maintenance tasks.
>
> The first commit introduces a GIT_TEST_LEGACY_DELETE environment variable to
> simulate legacy (pre-POSIX) delete semantics on modern Windows, so the
> regression test can verify the fix even on Windows 11.
>
> This fixes https://github.com/git-for-windows/git/issues/6210.
>
> Changes since v1:
>
> * The code now uses git_env_bool() as appropriate (thanks Patrick!)
This version looks good to me, thanks!
Patrick
^ permalink raw reply
* Re: [PATCH v4 5/5] format-rev: introduce builtin for on-demand pretty formatting
From: Kristoffer Haugsbakk @ 2026-05-08 13:25 UTC (permalink / raw)
To: git; +Cc: D. Ben Knoble, Phillip Wood, Ramsay Jones, Junio C Hamano
In-Reply-To: <V4_format-rev_new_builtin.6af@msgid.xyz>
On Thu, May 7, 2026, at 21:34, me myself wrote:
> From: Kristoffer Haugsbakk <code@khaugsbakk.name>
>[snip]
> +[[io]]
> +INPUT AND OUTPUT FORMAT
> +-----------------------
> +
> +The command uses newlines for both input and output termination by
> +default. See the `-z`, `--null-output`, and `--null-input` options for
> +using _NUL_ character as the terminator.
> +
> +The mode `--stdin-mode=revs` outputs one formatted commit followed by
> +the terminator. This could either be called a _line_ or a _record_ in
> +case "line" is too suggestive of newline termination.
> +
> +Note that this means that the terminator character (newline or _NUL_)
> +acts as a _terminator_, not a _separator_. In other words, the final
> +line or record is also terminated by the terminator character.
> +
> +The mode `--stdin-mode=text` replaces each object name with the
> +formatted commit, i.e. the format `%s` would transform the object name
> +`abcdef012...` to `<subject>` without any termination. Like this:
> +
> +----
> +Did we not fix this in "<subject>"?
> +----
> +
> +Regarding input in this mode: using `-z` or `--null-input` makes sure
> +that _NUL_ characters in the input are passed through correctly.
This was the paragraph that I was unhappy with (see cover letter).
We’re supposed to be dealing with text here. So on second thought I
don’t think we need to fuzz about passing through NUL characters.
Instead I could mention that `-z` for this mode allows you to further
transform running text from other commands that use NUL
termination. Like `git last-modified -z` (see the Examples section).
> +
> +It is safe to interactively read and write from this command since each
> +record is immediately flushed.
> +
> +[[examples]]
> +EXAMPLES
> +--------
> +
> +The command linkgit:git-last-modified[1] shows the commit that each file
> +was last modified in.
>[snip]
^ permalink raw reply
* Re: [PATCH] t5551: "GIT_TEST_LONG=Yes make test" is broken
From: Jeff King @ 2026-05-08 14:03 UTC (permalink / raw)
To: Junio C Hamano; +Cc: git, Derrick Stolee
In-Reply-To: <xmqqqznmeaco.fsf@gitster.g>
On Fri, May 08, 2026 at 02:31:03PM +0900, Junio C Hamano wrote:
> The "test_expect_success 'tag following always works over v0 http'"
> test in t5551 fails when it tries to run "git init tags", but this
> happens only when EXPENSIVE test is allowed to run.
>
> This is because the step tries to create a repository with "git init
> tags" but the EXPENSIVE test that runs way before it creates and
> leaves around a temporary file "tags". Have the EXPENSIVE test
> clean it up after itself.
I wondered how and when this broke, but it looks like it has been since
2024 when the later v0 test was added. And it looks like I am the
culprit for both the EXPENSIVE test adding the "tags" file and the v0
test assuming the path is available. :)
Anyway, this seems like the obviously correct solution.
-Peff
^ permalink raw reply
* Re: [PATCH] git-jump: pick a mode automatically when invoked without arguments
From: Jeff King @ 2026-05-08 14:13 UTC (permalink / raw)
To: Greg Hurrell via GitGitGadget; +Cc: git, Greg Hurrell
In-Reply-To: <pull.2108.git.1778231254871.gitgitgadget@gmail.com>
On Fri, May 08, 2026 at 09:07:34AM +0000, Greg Hurrell via GitGitGadget wrote:
> From: Greg Hurrell <greg.hurrell@datadoghq.com>
>
> When `git jump` is invoked with no positional arguments (and no
> arguments after `--stdout`) it currently prints usage and exits with
> status 1.
>
> But there are two situations where we can usefully infer the most
> valuable and likely mode that a user would want to use, and select it
> automatically when they run `git jump` without arguments:
>
> 1. When there are unmerged paths in the index, the user likely
> wants `git jump merge`.
>
> 2. When the working tree has unstaged changes, the user likely
> wants `git jump diff`.
>
> Detect these two cases and dispatch to the corresponding mode
> automatically, falling back to the existing usage-and-exit behavior
> when neither holds.
OK, I guess this saves a little bit of typing. I never really thought
about it because I long ago aliased the various invocations in my shell
("git jump diff" in particular is so useful that it is just "d" in my
shell).
I'd be a little worried that it is more confusing to somebody
approaching the command for the first time and just runs "git jump" to
not see usage or other guidance. But that might be overly paranoid.
Would having "git jump auto" work for you? I.e., are you primarily
trying to avoid the mental effort of selecting the command, or the
finger effort of typing it?
> if test $# -lt 1; then
> - usage >&2
> - exit 1
> + if test "$(git rev-parse --is-inside-work-tree 2>/dev/null)" != "true"; then
> + usage >&2
> + exit 1
> + fi
> + if test -n "$(git ls-files -u)"; then
> + set -- merge
> + elif ! git diff --quiet; then
> + set -- diff
> + else
> + usage >&2
> + exit 1
> + fi
The implementation looks reasonable. In theory we could save a diff
invocation by trying diff mode and reporting whether it found anything.
But the --quiet invocation is not too expensive, and avoiding it is
probably not worth the gymnastics required.
-Peff
^ permalink raw reply
* Re: [PATCH v2 0/6] mingw: stop using nedmalloc
From: Jeff King @ 2026-05-08 14:15 UTC (permalink / raw)
To: Junio C Hamano
Cc: Johannes Schindelin via GitGitGadget, git, Patrick Steinhardt,
Johannes Schindelin
In-Reply-To: <xmqqfr42fw30.fsf@gitster.g>
On Fri, May 08, 2026 at 11:56:19AM +0900, Junio C Hamano wrote:
> "Johannes Schindelin via GitGitGadget" <gitgitgadget@gmail.com>
> writes:
>
> > The patches that remove the vendored sources have a slightly unusual shape:
> > the Git mailing list rejects messages over 100kB and
> > compat/nedmalloc/malloc.c.h alone is ~196kB of source, so the deletion of
> > that file is split at section boundaries into three commits, each
> > comfortably under the cap.
>
> The history made strange only by the limitation of the tool (i.e.,
> mailing list) we use is like the tail wagging the dog. Could you
> give a commit log message that describes droppage of everything done
> in the "artificially stepwise only due to mailing list limitation,
> but we wish we could do in a single step because the separation is
> not logical at all" in the later steps, to the first of such steps
> ([2/6], I presume), and give each remaining patch a single liner "to
> be squashed into [2/6]" log message, or something? Then I can
> squash them on my end. Alternatively for this one only after we get
> favourable reviews on the early two steps to drop the use of the
> library, I can pull a single "discard everything" patch that builds
> on these two from your repository.
Could this be a good time to use --irreversible-delete? It is not like
humans are going to read the 200k of deletion hunks anyway.
-Peff
^ permalink raw reply
* [PATCH v2] ignore: note info/exclude lives in GIT_COMMON_DIR, not GIT_DIR
From: D. Ben Knoble @ 2026-05-08 14:14 UTC (permalink / raw)
To: git
Cc: D. Ben Knoble, brian m . carlson, Patrick Steinhardt, Taylor Blau,
Caleb White, Calvin Wan, Junio C Hamano, Elijah Newren,
Andrew Berry, Jeff King, Derrick Stolee, Phillip Wood
In-Reply-To: <e3ee0a11b566dd2cc605447c111ae4620bce0fe6.1777050300.git.ben.knoble+github@gmail.com>
gitignore(5) says that the per-repository ignore file is
$GIT_DIR/info/exclude, but in a worktree that is not the case:
git rev-parse --git-path info/exclude
/path/to/main/worktree/.git/info/exclude
git rev-parse --git-common-dir
/path/to/main/worktree/.git
We actually use $GIT_COMMON_DIR/info/exclude. Adjust the documentation
to say so.
Signed-off-by: D. Ben Knoble <ben.knoble+github@gmail.com>
---
Notes (benknoble/commits):
Changes in v2:
Only adjust the documentation.
brian points out that a more general extension would allow using more
info/ files as "per-worktree," which I don't have the impetus to
implement myself.
Phillip and Junio asked for a concrete use case:
A colleague is developing a tool for managing the "skill files" of
various LLM tools (Claude, Windsurf, etc.). The files have
requirements that make it hard to generically ignore them (e.g.,
filenames and front-matter have to match), but different tasks
(corresponding to worktrees) may want different active skills, so it
is desirable to ignore the files. Think of this like node_modules.
Unfortunately, since per-worktree ignores don't work, the current
solution is to put a .gitignore file in the corresponding directory
with the installed skills that ignores itself and the installed
skills.
Since overall reactions seem fairly negative (or require a more general
extension, which I think is probably the right course but not simply
implemented), I've opted to adjust the docs. They originally confused
me, as I was surprised when my colleague reported that per-worktree
ignores didn't work (the docs imply they should by use of $GIT_DIR).
Link to v1: <e3ee0a11b566dd2cc605447c111ae4620bce0fe6.1777050300.git.ben.knoble+github@gmail.com>
v1 notes:
Discussed briefly at https://lore.kernel.org/git/CALnO6CCXmA+ATT7CuyWkU6P8qmLCCpMi5Ppr1c78s0heznpVyw@mail.gmail.com/T
This is based on next (4f69b47b94 (Merge branch 'ps/test-set-e-clean'
into next, 2026-04-23)) but cleanly applies to master (94f057755b (Git
2.54, 2026-04-19)) and seen (50541634cb (Merge branch
'js/parseopt-subcommand-autocorrection' into seen, 2026-04-23)).
Documentation/gitignore.adoc | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/Documentation/gitignore.adoc b/Documentation/gitignore.adoc
index a3d24e5c34..c423b650de 100644
--- a/Documentation/gitignore.adoc
+++ b/Documentation/gitignore.adoc
@@ -7,7 +7,7 @@ gitignore - Specifies intentionally untracked files to ignore
SYNOPSIS
--------
-$XDG_CONFIG_HOME/git/ignore, $GIT_DIR/info/exclude, .gitignore
+$XDG_CONFIG_HOME/git/ignore, $GIT_COMMON_DIR/info/exclude, .gitignore
DESCRIPTION
-----------
@@ -34,7 +34,7 @@ precedence, the last matching pattern decides the outcome):
includes such `.gitignore` files in its repository, containing patterns for
files generated as part of the project build.
- * Patterns read from `$GIT_DIR/info/exclude`.
+ * Patterns read from `$GIT_COMMON_DIR/info/exclude`.
* Patterns read from the file specified by the configuration
variable `core.excludesFile`.
base-commit: 4f69b47b940100b02630f745a52f9d9850f122b2
--
2.54.0.564.ge3ee0a11b5.dirty
^ permalink raw reply related
* Re: [PATCH] git-jump: pick a mode automatically when invoked without arguments
From: Greg Hurrell @ 2026-05-08 14:30 UTC (permalink / raw)
To: Jeff King, Greg Hurrell; +Cc: git, Gregory Luke Hurrell Stewart
In-Reply-To: <20260508141314.GB709299@coredump.intra.peff.net>
On Fri, May 8, 2026, at 4:13 PM, Jeff King wrote:
> On Fri, May 08, 2026 at 09:07:34AM +0000, Greg Hurrell via GitGitGadget wrote:
>
> I'd be a little worried that it is more confusing to somebody
> approaching the command for the first time and just runs "git jump" to
> not see usage or other guidance. But that might be overly paranoid.
Hopefully, they at least read the README before installing it from contrib/
(although Homebrew recently starting installing it for folks automatically,
so may not remain true for much longer on macOS...)
> Would having "git jump auto" work for you? I.e., are you primarily
> trying to avoid the mental effort of selecting the command, or the
> finger effort of typing it?
It's mostly the finger effort of typing it because I generally know exactly
which mode I want; eg.
- I'm in the middle of a rebase, and hit a conflict; 100% of the time,
I want to explore the conflicts, so I want `git jump` to do `git jump
merge`.
- I have unstaged changes, and I want to make some tweaks before committing;
so I want `git jump` to do `git jump diff`.
- Otherwise, I'm wanting to search for something (ie. `git jump grep`),
so by definition I'm going to be doing some extra typing anyway (ie.
`git jump grep <pattern>`).
This is muscle memory for me at this point, because I've had a `git jump`
alias for this in my dotfiles[^1] for a couple of years. Homebrew
installing `git-jump` by default a few months ago[^2] broke this, because
aliases can't shadow builtin commands.
[^1]: https://github.com/wincent/wincent/commit/99183f86fe35
[^2]: https://github.com/Homebrew/homebrew-core/commit/e9fc066240f2
Best wishes,
Greg
^ permalink raw reply
* Re: [PATCH v2 0/9] doc: interpret-trailers: explain key format
From: Kristoffer Haugsbakk @ 2026-05-08 15:01 UTC (permalink / raw)
To: git; +Cc: Christian Couder, jackmanb, Linus Arver, D. Ben Knoble
In-Reply-To: <V2_CV_doc_int-tr_key_format.613@msgid.xyz>
On Mon, Apr 13, 2026, at 12:20, kristofferhaugsbakk@fastmail.com wrote:
> From: Kristoffer Haugsbakk <code@khaugsbakk.name>
>[snip]
Sorry to Ben here who I forgot to set on copy. :/
+Cc now.
^ permalink raw reply
* Re: [PATCH v2 9/9] doc: intepret-trailers: document comment line treatment
From: Kristoffer Haugsbakk @ 2026-05-08 15:03 UTC (permalink / raw)
To: Junio C Hamano
Cc: git, Christian Couder, jackmanb, Linus Arver, D. Ben Knoble
In-Reply-To: <xmqq5x5ulv41.fsf@gitster.g>
On Mon, Apr 13, 2026, at 17:48, Junio C Hamano wrote:
> "Kristoffer Haugsbakk" <kristofferhaugsbakk@fastmail.com> writes:
>
>>> [PATCH v2 9/9] doc: intepret-trailers: document comment line treatment
>>
>> s/intepret-trailers/interpret-trailers/
>>
>> Didn’t line up
>
> Yup, looking at [0/9], I agree.
Junio fixed this up when applying. That’s why I didn’t send
a new version.
A by-the-way for others here.
^ permalink raw reply
* [PATCH] commit-reach: early exit paint_down_to_common for single merge-base
From: Kristofer Karlsson via GitGitGadget @ 2026-05-08 15:07 UTC (permalink / raw)
To: git; +Cc: Derrick Stolee, Kristofer Karlsson, Kristofer Karlsson
From: Kristofer Karlsson <krka@spotify.com>
When find_all is false and generation numbers are available, the
priority queue pops in non-increasing generation order. The first
doubly-painted commit is a valid best merge-base; no later commit
can dominate it. Skip the expensive STALE drain in this case.
The early exit is guarded by three conditions: find_all must be
false, the commit-graph must provide generation numbers, and the
merge-base commit itself must have a finite generation (not
GENERATION_NUMBER_INFINITY from being outside the commit-graph).
Add find_all parameter to repo_get_merge_bases_many_dirty() and
thread it through to paint_down_to_common(). git merge-base
(without --all) passes show_all=0, triggering the early exit.
On a 2.2M-commit merge-heavy monorepo with commit-graph:
HEAD vs ~500: 5,229ms -> 24ms
HEAD vs ~1000: 4,214ms -> 39ms
HEAD vs ~5000: 3,799ms -> 46ms
HEAD vs ~10000: 3,827ms -> 61ms
Signed-off-by: Kristofer Karlsson <krka@spotify.com>
---
[RFC] commit-reach: skip STALE drain when only one merge-base needed
Context for what this is all about.
I am working with a very large git monorepo and have been investigating
performance issue. After some digging I ended up looking more deeply
into git merge-base. I saw it had an --all parameter but the default is
to only return a single merge-base. Looking through the code and adding
debug timing, I realized that although the total time to compute the
merge-base was high, a very small amount of time was spent finding the
initial merge-base value that was later returned.
The optimization is actually quite dramatic in a large repo - runtime
went down from 5000ms to 50ms, so it's roughly a 100x optimization. This
comes from an exploding frontier of STALE commits to drain.
Thus, my idea is simply to return early from the function once we know
what will be returned. This only works if we find a candidate that we
know will not be pruned later - but fortunately if we have a commit
graph with generations we will visit commits in order such that it will
actually not be pruned.
Published-As: https://github.com/gitgitgadget/git/releases/tag/pr-2109%2Fspkrka%2Fmerge-base-early-exit-v1
Fetch-It-Via: git fetch https://github.com/gitgitgadget/git pr-2109/spkrka/merge-base-early-exit-v1
Pull-Request: https://github.com/gitgitgadget/git/pull/2109
builtin/merge-base.c | 3 +-
commit-reach.c | 26 ++++++---
commit-reach.h | 5 +-
t/t6010-merge-base.sh | 119 ++++++++++++++++++++++++++++++++++++++++++
t/t6600-test-reach.sh | 40 ++++++++++++++
5 files changed, 183 insertions(+), 10 deletions(-)
diff --git a/builtin/merge-base.c b/builtin/merge-base.c
index c7ee97fa6a..6b9d42f596 100644
--- a/builtin/merge-base.c
+++ b/builtin/merge-base.c
@@ -14,7 +14,8 @@ static int show_merge_base(struct commit **rev, size_t rev_nr, int show_all)
struct commit_list *result = NULL, *r;
if (repo_get_merge_bases_many_dirty(the_repository, rev[0],
- rev_nr - 1, rev + 1, &result) < 0) {
+ rev_nr - 1, rev + 1,
+ show_all, &result) < 0) {
commit_list_free(result);
return -1;
}
diff --git a/commit-reach.c b/commit-reach.c
index d3a9b3ed6f..c9d2d594de 100644
--- a/commit-reach.c
+++ b/commit-reach.c
@@ -55,14 +55,16 @@ static int paint_down_to_common(struct repository *r,
struct commit **twos,
timestamp_t min_generation,
int ignore_missing_commits,
+ int find_all,
struct commit_list **result)
{
struct prio_queue queue = { compare_commits_by_gen_then_commit_date };
int i;
+ int has_gens = min_generation || corrected_commit_dates_enabled(r);
timestamp_t last_gen = GENERATION_NUMBER_INFINITY;
struct commit_list **tail = result;
- if (!min_generation && !corrected_commit_dates_enabled(r))
+ if (!has_gens)
queue.compare = compare_commits_by_commit_date;
one->object.flags |= PARENT1;
@@ -97,6 +99,11 @@ static int paint_down_to_common(struct repository *r,
if (!(commit->object.flags & RESULT)) {
commit->object.flags |= RESULT;
tail = commit_list_append(commit, tail);
+ /* Generation-ordered queue: no later
+ * commit can dominate this one. */
+ if (!find_all && has_gens &&
+ generation < GENERATION_NUMBER_INFINITY)
+ break;
}
/* Mark parents of a found merge stale */
flags |= STALE;
@@ -136,6 +143,7 @@ static int paint_down_to_common(struct repository *r,
static int merge_bases_many(struct repository *r,
struct commit *one, int n,
struct commit **twos,
+ int find_all,
struct commit_list **result)
{
struct commit_list *list = NULL, **tail = result;
@@ -165,7 +173,7 @@ static int merge_bases_many(struct repository *r,
oid_to_hex(&twos[i]->object.oid));
}
- if (paint_down_to_common(r, one, n, twos, 0, 0, &list)) {
+ if (paint_down_to_common(r, one, n, twos, 0, 0, find_all, &list)) {
commit_list_free(list);
return -1;
}
@@ -246,7 +254,7 @@ static int remove_redundant_no_gen(struct repository *r,
min_generation = curr_generation;
}
if (paint_down_to_common(r, array[i], filled,
- work, min_generation, 0, &common)) {
+ work, min_generation, 0, 1, &common)) {
clear_commit_marks(array[i], all_flags);
clear_commit_marks_many(filled, work, all_flags);
commit_list_free(common);
@@ -425,6 +433,7 @@ static int get_merge_bases_many_0(struct repository *r,
size_t n,
struct commit **twos,
int cleanup,
+ int find_all,
struct commit_list **result)
{
struct commit_list *list, **tail = result;
@@ -432,7 +441,7 @@ static int get_merge_bases_many_0(struct repository *r,
size_t cnt, i;
int ret;
- if (merge_bases_many(r, one, n, twos, result) < 0)
+ if (merge_bases_many(r, one, n, twos, find_all, result) < 0)
return -1;
for (i = 0; i < n; i++) {
if (one == twos[i])
@@ -475,16 +484,17 @@ int repo_get_merge_bases_many(struct repository *r,
struct commit **twos,
struct commit_list **result)
{
- return get_merge_bases_many_0(r, one, n, twos, 1, result);
+ return get_merge_bases_many_0(r, one, n, twos, 1, 1, result);
}
int repo_get_merge_bases_many_dirty(struct repository *r,
struct commit *one,
size_t n,
struct commit **twos,
+ int find_all,
struct commit_list **result)
{
- return get_merge_bases_many_0(r, one, n, twos, 0, result);
+ return get_merge_bases_many_0(r, one, n, twos, 0, find_all, result);
}
int repo_get_merge_bases(struct repository *r,
@@ -492,7 +502,7 @@ int repo_get_merge_bases(struct repository *r,
struct commit *two,
struct commit_list **result)
{
- return get_merge_bases_many_0(r, one, 1, &two, 1, result);
+ return get_merge_bases_many_0(r, one, 1, &two, 1, 1, result);
}
/*
@@ -555,7 +565,7 @@ int repo_in_merge_bases_many(struct repository *r, struct commit *commit,
if (paint_down_to_common(r, commit,
nr_reference, reference,
- generation, ignore_missing_commits, &bases))
+ generation, ignore_missing_commits, 1, &bases))
ret = -1;
else if (commit->object.flags & PARENT2)
ret = 1;
diff --git a/commit-reach.h b/commit-reach.h
index 6012402dfc..908b9539c5 100644
--- a/commit-reach.h
+++ b/commit-reach.h
@@ -17,10 +17,13 @@ int repo_get_merge_bases_many(struct repository *r,
struct commit *one, size_t n,
struct commit **twos,
struct commit_list **result);
-/* To be used only when object flags after this call no longer matter */
+/* To be used only when object flags after this call no longer matter.
+ * When find_all is false and generation numbers are available, returns
+ * after finding the first merge-base, skipping the STALE drain. */
int repo_get_merge_bases_many_dirty(struct repository *r,
struct commit *one, size_t n,
struct commit **twos,
+ int find_all,
struct commit_list **result);
int get_octopus_merge_bases(struct commit_list *in, struct commit_list **result);
diff --git a/t/t6010-merge-base.sh b/t/t6010-merge-base.sh
index 44c726ea39..f6c85d4f53 100755
--- a/t/t6010-merge-base.sh
+++ b/t/t6010-merge-base.sh
@@ -305,4 +305,123 @@ test_expect_success 'merge-base --octopus --all for complex tree' '
test_cmp expected actual
'
+# The following tests verify that "git merge-base" (without --all)
+# returns the same result with and without a commit-graph.
+# This exercises the early-exit optimisation in paint_down_to_common
+# that skips the STALE drain when generation numbers are available.
+
+test_expect_success 'setup for commit-graph tests' '
+ git init graph-repo &&
+ (
+ cd graph-repo &&
+
+ # Build a forked DAG:
+ #
+ # L1---L2 (left)
+ # /
+ # S
+ # \
+ # R1---R2 (right)
+ #
+ test_commit GS &&
+ git checkout -b left &&
+ test_commit L1 &&
+ test_commit L2 &&
+ git checkout GS &&
+ git checkout -b right &&
+ test_commit GR1 &&
+ test_commit GR2
+ )
+'
+
+test_expect_success 'merge-base without commit-graph' '
+ (
+ cd graph-repo &&
+ rm -f .git/objects/info/commit-graph &&
+ git merge-base left right >actual &&
+ git rev-parse GS >expected &&
+ test_cmp expected actual
+ )
+'
+
+test_expect_success 'merge-base with commit-graph' '
+ (
+ cd graph-repo &&
+ git commit-graph write --reachable &&
+ git merge-base left right >actual &&
+ git rev-parse GS >expected &&
+ test_cmp expected actual
+ )
+'
+
+test_expect_success 'merge-base --all with commit-graph' '
+ (
+ cd graph-repo &&
+ git merge-base --all left right >actual &&
+ git rev-parse GS >expected &&
+ test_cmp expected actual
+ )
+'
+
+test_expect_success 'merge-base agrees with --all for single result' '
+ (
+ cd graph-repo &&
+ git commit-graph write --reachable &&
+ git merge-base left right >actual.single &&
+ git merge-base --all left right >actual.all &&
+ test_cmp actual.all actual.single
+ )
+'
+
+test_expect_success 'setup for deep chain commit-graph test' '
+ git init deep-repo &&
+ (
+ cd deep-repo &&
+
+ # Build a deep forked DAG:
+ #
+ # L1--L2--...--L20 (left)
+ # /
+ # S
+ # \
+ # R1--R2--...--R20 (right)
+ #
+ test_commit DS &&
+ git checkout -b left &&
+ for i in $(test_seq 1 20)
+ do
+ test_commit DL$i || return 1
+ done &&
+ git checkout DS &&
+ git checkout -b right &&
+ for i in $(test_seq 1 20)
+ do
+ test_commit DR$i || return 1
+ done
+ )
+'
+
+test_expect_success 'deep chain: merge-base matches with and without commit-graph' '
+ (
+ cd deep-repo &&
+ rm -f .git/objects/info/commit-graph &&
+ git merge-base left right >actual.no-graph &&
+ git rev-parse DS >expected &&
+ test_cmp expected actual.no-graph &&
+ git commit-graph write --reachable &&
+ git merge-base left right >actual.graph &&
+ test_cmp expected actual.graph
+ )
+'
+
+test_expect_success 'deep chain: --all and non---all agree with commit-graph' '
+ (
+ cd deep-repo &&
+ git commit-graph write --reachable &&
+ git merge-base left right >actual.single &&
+ git merge-base --all left right >actual.all &&
+ test_cmp actual.all actual.single
+ )
+'
+
test_done
diff --git a/t/t6600-test-reach.sh b/t/t6600-test-reach.sh
index dc0421ed2f..51c23b7683 100755
--- a/t/t6600-test-reach.sh
+++ b/t/t6600-test-reach.sh
@@ -882,4 +882,44 @@ test_expect_success 'rev-list --maximal-only matches merge-base --independent' '
test_cmp expect.sorted actual.sorted
'
+# The following tests verify the early-exit optimisation in
+# paint_down_to_common when merge-base is invoked without --all.
+# Each test checks all four commit-graph configurations.
+
+merge_base_all_modes () {
+ test_when_finished rm -rf .git/objects/info/commit-graph &&
+ git merge-base "$@" >actual &&
+ test_cmp expect actual &&
+ cp commit-graph-full .git/objects/info/commit-graph &&
+ git merge-base "$@" >actual &&
+ test_cmp expect actual &&
+ cp commit-graph-half .git/objects/info/commit-graph &&
+ git merge-base "$@" >actual &&
+ test_cmp expect actual &&
+ cp commit-graph-no-gdat .git/objects/info/commit-graph &&
+ git merge-base "$@" >actual &&
+ test_cmp expect actual
+}
+
+test_expect_success 'merge-base without --all (unique base)' '
+ git rev-parse commit-5-3 >expect &&
+ merge_base_all_modes commit-5-7 commit-8-3
+'
+
+test_expect_success 'merge-base without --all is one of --all results' '
+ test_when_finished rm -rf .git/objects/info/commit-graph &&
+
+ cp commit-graph-full .git/objects/info/commit-graph &&
+ git merge-base --all commit-5-7 commit-4-8 commit-6-6 commit-8-3 >all &&
+ git merge-base commit-5-7 commit-4-8 commit-6-6 commit-8-3 >single &&
+ test_line_count = 1 single &&
+ grep -F -f single all &&
+
+ cp commit-graph-half .git/objects/info/commit-graph &&
+ git merge-base --all commit-5-7 commit-4-8 commit-6-6 commit-8-3 >all &&
+ git merge-base commit-5-7 commit-4-8 commit-6-6 commit-8-3 >single &&
+ test_line_count = 1 single &&
+ grep -F -f single all
+'
+
test_done
base-commit: 94f057755b7941b321fd11fec1b2e3ca5313a4e0
--
gitgitgadget
^ permalink raw reply related
* Re: [PATCH] Makefile: link osxkeychain helper against Rust
From: Shnatu @ 2026-05-08 17:44 UTC (permalink / raw)
To: koji.nakamaru; +Cc: git, gitgitgadget, gitster, sandals, snatu
In-Reply-To: <CAOTNsDyygMEz4dgfkWKb=wWP0g9MhNFgDHzPPEODbMGmDQLTOQ@mail.gmail.com>
Thank you for the suggestion! This is indeed a much cleaner approach.
By wrapping `RUST_LIB` and the rust targets in `ifndef NO_RUST`, we can link `git-credential-osxkeychain` directly against `$(RUST_LIB)` without needing to introduce an intermediate `RUST_LIBS` variable. When `NO_RUST` is defined, `$(RUST_LIB)` evaluates to empty, and Make naturally links it as a pure C binary without any Rust dependencies.
To integrate this with the universal build support (`RUST_TARGETS`/`lipo`) introduced in this PR, I have updated the changes to:
- Wrap the `RUST_LIB` definition block (which resolves target-specific paths for universal builds) in ifndef `NO_RUST`.
- Wrap the entire universal compilation and lipo combining block in ifndef `NO_RUST`.
- Remove the `RUST_LIBS` helper variable and use `$(RUST_LIB)` directly in `git-credential-osxkeychain`.
^ permalink raw reply
* Re: [PATCH] git-jump: pick a mode automatically when invoked without arguments
From: Jeff King @ 2026-05-08 17:52 UTC (permalink / raw)
To: Greg Hurrell; +Cc: Greg Hurrell, git, Gregory Luke Hurrell Stewart
In-Reply-To: <c5e0a1fa-f228-41dd-b547-07b0ad6c0964@app.fastmail.com>
On Fri, May 08, 2026 at 04:30:36PM +0200, Greg Hurrell wrote:
> On Fri, May 8, 2026, at 4:13 PM, Jeff King wrote:
> > On Fri, May 08, 2026 at 09:07:34AM +0000, Greg Hurrell via GitGitGadget wrote:
> >
> > I'd be a little worried that it is more confusing to somebody
> > approaching the command for the first time and just runs "git jump" to
> > not see usage or other guidance. But that might be overly paranoid.
>
> Hopefully, they at least read the README before installing it from contrib/
> (although Homebrew recently starting installing it for folks automatically,
> so may not remain true for much longer on macOS...)
Yeah, I'd hope so. And even if it might be more discoverable, I'm not
sure that is more important than being convenient for experienced users.
I guess a config option would be possible, but probably not worth it for
something as trivial as git-jump.
> It's mostly the finger effort of typing it because I generally know exactly
> which mode I want; eg.
OK, that makes sense.
> This is muscle memory for me at this point, because I've had a `git jump`
> alias for this in my dotfiles[^1] for a couple of years. Homebrew
> installing `git-jump` by default a few months ago[^2] broke this, because
> aliases can't shadow builtin commands.
Ah, yeah, that is frustrating. We try to avoid aliases overrides to
prevent confusion, but for an add-on tool like git-jump I think it is
overly cautious. It might be reasonable to limit that protection only to
commands in Git's exec-path, but I haven't thought hard about it. And I
think it should be considered separately from this patch anyway.
So yeah, your patch looks good to me. Thanks.
-Peff
^ permalink raw reply
* unexpected auto-maintenance, was Re: git hogs the CPU, RAM and storage despite its config
From: Jeff King @ 2026-05-08 18:03 UTC (permalink / raw)
To: jean-christophe manciot; +Cc: git, Derrick Stolee
In-Reply-To: <CAKcFC3arsYExb5dCMQspo4V9UFDadFaj8Q4PUsMWZJw_eYrMzA@mail.gmail.com>
On Mon, May 04, 2026 at 05:27:21PM +0200, jean-christophe manciot wrote:
> [gc]
> auto = 0
This is enough to disable auto-gc. But these days we also (instead?) run
git-maintenance, which is controlled by maintenance.auto. So you
probably are getting a bunch of background git-maintenance runs kicked
off.
> [pack]
> threads = 1
> windowMemory = 1g
>
> I expected git to use maximum one thread for packing and I'm surprised
> it even tried to perform packing as gc.auto was disabled.
This should work to tell pack-objects to use only one thread, but that
is one thread per invocation. And we were probably kicking off a ton of
processes due to the background maintenance (and worse, they were all
doing the same work redundantly and maybe even stepping on each others
toes).
+cc Stolee for wisdom on all things git-maintenance.
Should maintenance.auto fall back to gc.auto for compatibility and
avoiding unwanted surprises when people upgrade?
Also, should background maintenance be locking to avoid multiple runs?
It does not seem to do so, and if I run:
git init
for i in $(seq 10000); do
echo $i >>file
git add file
git commit -m "commit $i"
done
I get several concurrent pack-objects processes. After a few thousand
commits I got bored and hit ^C, and the resulting repo was corrupt!
Which is not too surprising, as multiple simultaneous repacks are known
to be unsafe, but means we should probably avoid them.
-Peff
^ permalink raw reply
* Re: [PATCH v2 01/11] index-pack, unpack-objects: use size_t for object size
From: Torsten Bögershausen @ 2026-05-08 19:09 UTC (permalink / raw)
To: Johannes Schindelin
Cc: Johannes Schindelin via GitGitGadget, git, Derrick Stolee,
Jeff King
In-Reply-To: <fa39d84b-ddbc-3943-5cca-078fb18db80d@gmx.de>
On Fri, May 08, 2026 at 09:36:53AM +0200, Johannes Schindelin wrote:
> Hi Torsten,
>
> On Tue, 5 May 2026, Torsten Bögershausen wrote:
>
> > On Mon, May 04, 2026 at 05:08:18PM +0000, Johannes Schindelin via GitGitGadget wrote:
> > > From: Johannes Schindelin <johannes.schindelin@gmx.de>
> > >
> > > [...]
> > > @@ -524,7 +524,8 @@ static void *unpack_raw_entry(struct object_entry *obj,
> > > struct object_id *oid)
> > > {
> > > unsigned char *p;
> > > - unsigned long size, c;
> > > + size_t size;
> > > + unsigned long c;
> >
> > Does this look a little bit strange ?
>
> Good point.
>
> > p points to an unsigned char (better would be *uint8_t)
> > then it is dereferenced into an "unsigned long".
> > Then it is masked with 0x7f
> > In short: should "c" be declared as uint8_t ?
>
> Almost. It should be a `size_t`, so that we don't have to cast it when
> shifting it. I'll include a fix in the next iteration.
I think I was not very clear here.
De-referencing a long (or size_t) from any address is something
I would try to avoid:
Some processors do not like to read a 32 or 64 bit value from
an uneven address (and throw an exeption).
x86 processors just handle it, using more than one bus cycle.
In short: Please keep the up-cast and simply read an uint8_t.
^ permalink raw reply
* Re: [BUG] "git diff --word-diff" gives a diff while they are only space changes
From: Vincent Lefevre @ 2026-05-08 21:39 UTC (permalink / raw)
To: Johannes Sixt; +Cc: git
In-Reply-To: <7cedf86c-5db7-45ef-b8d4-034b792f0def@kdbg.org>
On 2026-05-08 14:48:01 +0200, Johannes Sixt wrote:
> This is expected behavior.
>
> git diff --word-diff is not agnostic to whitespace; if you drop
> --word-diff, you see the line-diff that the word-diff is based on. If
> you want whitespace-agnostic word-diff, you have to add -w.
This is not how it is documented. Even when using "git diff" without
--word-diff, but with GNU wdiff instead, the output is fine:
$ git diff file1 file2 | wdiff -d
diff --git a/file1 b/file2
index da04344..0074613 100644
[--- a/file1-]
{+++ b/file2+}
@@ -1,5 +1,5 @@
1
2
3
2
4
--
Vincent Lefèvre <vincent@vinc17.net> - Web: <https://www.vinc17.net/>
100% accessible validated (X)HTML - Blog: <https://www.vinc17.net/blog/>
Work: CR INRIA - computer arithmetic / Pascaline project (LIP, ENS-Lyon)
^ permalink raw reply
* [PATCH] checkout: add --fetch to fetch remote before resolving start-point
From: Harald Nordgren @ 2026-05-08 22:40 UTC (permalink / raw)
To: phillip.wood123
Cc: ben.knoble, git, gitgitgadget, haraldnordgren,
kristofferhaugsbakk, marcnarc, ramsay
In-Reply-To: <f23eb128-958f-475f-911b-eac4f6daddff@gmail.com>
> * "--track=inherit,direct" is nonsense and should be rejected
>
> * currently "--track" has "last one wins" behavior so
> "--track=inherit --track=direct" behaves like "--track=direct". We
> should probably keep that so that "--track=fetch --track=direct"
> behaves like "--track=direct", not "--track=fetch,direct"
>
> * if "git fetch" fails and the remote tracking ref already exists then
> we should print a warning and carry on rather than dying which is more
> convenient if the user or remote server are offline.
>
> * "git checkout --track=fetch origin/branch" should respect
> remote.origin.fetch so that we fetch the ref that we're going to
> checkout. I wonder if we can share this logic with the code that
> sets the upstream branch.
>
> * "git checkout --track=fetch origin" should only fetch the remote
> ref that we're going to checkout, not all the refs from origin. i.e.
> it should read origin/HEAD to work out what to fetch.
Good points!
Harald
^ permalink raw reply
* [PATCH v7] checkout: extend --track with a "fetch" mode to refresh start-point
From: Harald Nordgren via GitGitGadget @ 2026-05-08 22:52 UTC (permalink / raw)
To: git
Cc: Ramsay Jones, D. Ben Knoble, Kristoffer Haugsbakk, Marc Branchaud,
Phillip Wood, Harald Nordgren, Harald Nordgren
In-Reply-To: <pull.2281.v6.git.git.1777847487823.gitgitgadget@gmail.com>
From: Harald Nordgren <haraldnordgren@gmail.com>
If you want to fork your topic branch from the very latest of the
tip of a branch your remote has, you would do:
git fetch origin some-branch
git checkout -b new_branch --track origin/some-branch
Extend the "--track" option of "git checkout" and allow users to
write
git checkout -b new_branch --track=fetch origin/some-branch
to (1) fetch 'some-branch' from the remote 'origin', updating the
remote-tracking branch 'origin/some-branch', (2) arrange subsequent
'git pull' on 'new_branch' to interact with 'origin/some-branch' and
(3) fork 'new_branch' from it.
In the value of the '--track' option, 'fetch' can be combined with
the existing 'direct' (default) and 'inherit' modes via a
comma-separated list. Examples:
git checkout -b new_branch --track=fetch,inherit some_local_branch
git switch -c new_branch --track=fetch origin/some-branch
When "fetch" is requested and <start-point> is in <remote>/<branch>
form, run "git fetch <remote> <branch>" before resolving the ref, so
that other remote-tracking branches are left untouched. If
<start-point> is a bare remote name like "origin" (which resolves to
that remote's default branch), "git fetch <remote>" is run instead,
since the target branch is not known up front. Abort the checkout if
the fetch fails.
Signed-off-by: Harald Nordgren <haraldnordgren@gmail.com>
---
checkout: add --fetch to fetch remote before resolving start-point
* Reject --track=inherit,direct as mutually exclusive modes.
* Make repeated --track= last-one-wins: --track=fetch --track=direct
behaves like --track=direct.
* On fetch failure, warn and proceed from the existing remote-tracking
ref instead of aborting (friendlier when offline); only abort when
there is no existing ref.
* For --track=fetch <remote>/<branch>, resolve the source ref through
the configured remote.<name>.fetch refspec so custom refspecs fetch
the correct ref.
* For --track=fetch <remote>, read <remote>/HEAD and fetch only that
branch instead of the whole remote.
* Tests and docs updated accordingly.
Published-As: https://github.com/gitgitgadget/git/releases/tag/pr-git-2281%2FHaraldNordgren%2Fcheckout-fetch-start-point-v7
Fetch-It-Via: git fetch https://github.com/gitgitgadget/git pr-git-2281/HaraldNordgren/checkout-fetch-start-point-v7
Pull-Request: https://github.com/git/git/pull/2281
Range-diff vs v6:
1: 1b42c648b9 ! 1: de375d55f1 checkout: extend --track with a "fetch" mode to refresh start-point
@@ Documentation/git-checkout.adoc: of it").
--track without -b implies branch creation.
+
+The argument is a comma-separated list. `direct` (the default) and
-+`inherit` select the tracking mode. Adding `fetch` requests that the
-+remote be fetched before _<start-point>_ is resolved, so the new branch
-+starts from a fresh tip: when _<start-point>_ is in
-+_<remote>/<branch>_ form, only that branch is updated; when it is a
-+bare remote name (e.g. `origin`), the whole remote is fetched. If the
-+fetch fails, the checkout is aborted.
++`inherit` select the tracking mode and are mutually exclusive. Adding
++`fetch` requests that the remote be fetched before _<start-point>_ is
++resolved, so the new branch starts from a fresh tip: when
++_<start-point>_ is in _<remote>/<branch>_ form, only that branch is
++updated; when _<start-point>_ is a bare remote name (e.g. `origin`),
++only the remote's default branch is updated. If the fetch fails and the
++corresponding remote-tracking ref already exists, a warning is printed
++and the checkout proceeds from the existing tip; otherwise the checkout
++is aborted.
++
If no `-b` option is given, the name of the new branch will be
derived from the remote-tracking branch, by looking at the local part of
@@ Documentation/git-switch.adoc: should result in deletion of the path).
details.
+
+The argument is a comma-separated list. `direct` (the default) and
-+`inherit` select the tracking mode. Adding `fetch` requests that the
-+remote be fetched before _<start-point>_ is resolved, so the new branch
-+starts from a fresh tip: when _<start-point>_ is in
-+_<remote>/<branch>_ form, only that branch is updated; when it is a
-+bare remote name (e.g. `origin`), the whole remote is fetched. If the
-+fetch fails, the switch is aborted.
++`inherit` select the tracking mode and are mutually exclusive. Adding
++`fetch` requests that the remote be fetched before _<start-point>_ is
++resolved, so the new branch starts from a fresh tip: when
++_<start-point>_ is in _<remote>/<branch>_ form, only that branch is
++updated; when _<start-point>_ is a bare remote name (e.g. `origin`),
++only the remote's default branch is updated. If the fetch fails and the
++corresponding remote-tracking ref already exists, a warning is printed
++and the switch proceeds from the existing tip; otherwise the switch is
++aborted.
++
If no `-c` option is given, the name of the new branch will be derived
from the remote-tracking branch, by looking at the local part of the
@@ Documentation/git-switch.adoc: should result in deletion of the path).
## builtin/checkout.c ##
@@
+ #include "preload-index.h"
+ #include "read-cache.h"
+ #include "refs.h"
++#include "refspec.h"
+ #include "remote.h"
#include "repo-settings.h"
#include "resolve-undo.h"
#include "revision.h"
@@ builtin/checkout.c: struct branch_info {
char *checkout;
};
-+static void fetch_remote_for_start_point(const char *arg)
++static int resolve_fetch_target(const char *arg, char **remote_out,
++ char **src_ref_out)
+{
+ const char *slash;
+ char *remote_name;
+ struct remote *remote;
-+ struct child_process cmd = CHILD_PROCESS_INIT;
++ struct refspec_item query = { 0 };
++ struct strbuf dst = STRBUF_INIT;
++ const char *rest;
++
++ *remote_out = NULL;
++ *src_ref_out = NULL;
+
+ if (!arg || !*arg)
-+ return;
++ return -1;
+
+ slash = strchr(arg, '/');
+ if (slash == arg)
-+ return;
++ return -1;
+ remote_name = slash ? xstrndup(arg, slash - arg) : xstrdup(arg);
+
+ remote = remote_get(remote_name);
+ if (!remote || !remote_is_configured(remote, 1)) {
+ free(remote_name);
++ return -1;
++ }
++
++ rest = (slash && slash[1]) ? slash + 1 : NULL;
++ if (!rest) {
++ struct object_id oid;
++ const char *head_target;
++ const char *short_target;
++
++ strbuf_addf(&dst, "refs/remotes/%s/HEAD", remote_name);
++ head_target = refs_resolve_ref_unsafe(get_main_ref_store(the_repository),
++ dst.buf,
++ RESOLVE_REF_READING |
++ RESOLVE_REF_NO_RECURSE,
++ &oid, NULL);
++ strbuf_reset(&dst);
++ if (head_target &&
++ skip_prefix(head_target, "refs/remotes/", &short_target) &&
++ skip_prefix(short_target, remote_name, &short_target) &&
++ *short_target == '/')
++ rest = short_target + 1;
++ }
++
++ if (rest) {
++ strbuf_addf(&dst, "refs/remotes/%s/%s", remote_name, rest);
++ query.dst = dst.buf;
++ if (!remote_find_tracking(remote, &query) && query.src) {
++ *src_ref_out = xstrdup(query.src);
++ free(query.src);
++ } else {
++ *src_ref_out = xstrdup(rest);
++ }
++ }
++
++ strbuf_release(&dst);
++ *remote_out = remote_name;
++ return 0;
++}
++
++static void fetch_remote_for_start_point(const char *arg)
++{
++ char *remote_name = NULL;
++ char *src_ref = NULL;
++ struct child_process cmd = CHILD_PROCESS_INIT;
++ struct strbuf dst_ref = STRBUF_INIT;
++ int have_existing_ref = 0;
++
++ if (resolve_fetch_target(arg, &remote_name, &src_ref))
+ return;
++
++ if (src_ref) {
++ const char *short_src = src_ref;
++ struct object_id oid;
++
++ skip_prefix(short_src, "refs/heads/", &short_src);
++ strbuf_addf(&dst_ref, "refs/remotes/%s/%s", remote_name, short_src);
++ if (!refs_read_ref(get_main_ref_store(the_repository),
++ dst_ref.buf, &oid))
++ have_existing_ref = 1;
+ }
+
+ strvec_pushl(&cmd.args, "fetch", remote_name, NULL);
-+ if (slash && slash[1])
-+ strvec_push(&cmd.args, slash + 1);
++ if (src_ref)
++ strvec_push(&cmd.args, src_ref);
+ cmd.git_cmd = 1;
++ if (run_command(&cmd)) {
++ if (have_existing_ref)
++ warning(_("failed to fetch start-point '%s'; "
++ "using existing '%s'"),
++ arg, dst_ref.buf);
++ else
++ die(_("failed to fetch start-point '%s'"), arg);
++ }
++
+ free(remote_name);
-+ if (run_command(&cmd))
-+ die(_("failed to fetch start-point '%s'"), arg);
++ free(src_ref);
++ strbuf_release(&dst_ref);
+}
+
+static int parse_opt_checkout_track(const struct option *opt,
@@ builtin/checkout.c: struct branch_info {
+ struct checkout_opts *opts = opt->value;
+ struct string_list tokens = STRING_LIST_INIT_DUP;
+ struct string_list_item *item;
++ int saw_direct = 0, saw_inherit = 0;
+ int ret = 0;
+
++ opts->fetch = 0;
++
+ if (unset) {
+ opts->track = BRANCH_TRACK_NEVER;
-+ opts->fetch = 0;
+ return 0;
+ }
+
@@ builtin/checkout.c: struct branch_info {
+ if (!strcmp(item->string, "fetch")) {
+ opts->fetch = 1;
+ } else if (!strcmp(item->string, "direct")) {
++ saw_direct = 1;
+ opts->track = BRANCH_TRACK_EXPLICIT;
+ } else if (!strcmp(item->string, "inherit")) {
++ saw_inherit = 1;
+ opts->track = BRANCH_TRACK_INHERIT;
+ } else {
+ ret = error(_("option `%s' expects \"%s\", \"%s\", "
+ "or \"%s\""),
+ "--track", "direct", "inherit", "fetch");
-+ break;
++ goto out;
+ }
+ }
+
++ if (saw_direct && saw_inherit)
++ ret = error(_("option `%s' cannot combine \"%s\" and \"%s\""),
++ "--track", "direct", "inherit");
++
++out:
+ string_list_clear(&tokens, 0);
+ return ret;
+}
@@ t/t7201-co.sh: test_expect_success 'tracking info copied with autoSetupMerge=inh
+ test "$(git rev-parse refs/remotes/fetch_upstream/fetch_other)" = "$other_before"
+'
+
-+test_expect_success 'checkout --track=fetch with bare remote name fetches the remote' '
++test_expect_success 'checkout --track=fetch with bare remote name fetches only <remote>/HEAD target' '
+ git checkout main &&
-+ git -C fetch_upstream checkout -b fetch_new2 &&
-+ test_commit -C fetch_upstream u_new2 &&
-+ test_must_fail git rev-parse --verify refs/remotes/fetch_upstream/fetch_new2 &&
++ git -C fetch_upstream checkout main &&
++ git remote set-head fetch_upstream main &&
++ git -C fetch_upstream checkout -b fetch_unrelated &&
++ test_commit -C fetch_upstream u_unrelated_pre &&
++ git fetch fetch_upstream fetch_unrelated &&
++ unrelated_before=$(git rev-parse refs/remotes/fetch_upstream/fetch_unrelated) &&
++ git -C fetch_upstream checkout main &&
++ test_commit -C fetch_upstream u_main_post &&
++ git -C fetch_upstream checkout fetch_unrelated &&
++ test_commit -C fetch_upstream u_unrelated_post &&
+ git checkout --track=fetch -b local_from_remote fetch_upstream &&
-+ git rev-parse --verify refs/remotes/fetch_upstream/fetch_new2
++ test_cmp_rev refs/remotes/fetch_upstream/main HEAD &&
++ test "$(git rev-parse refs/remotes/fetch_upstream/fetch_unrelated)" = "$unrelated_before"
+'
+
-+test_expect_success 'checkout --track=fetch aborts and does not create branch on fetch failure' '
++test_expect_success 'checkout --track=fetch aborts and does not create branch when no existing ref' '
+ git checkout main &&
+ test_might_fail git branch -D bogus &&
+ test_must_fail git checkout --track=fetch -b bogus fetch_upstream/does_not_exist &&
+ test_must_fail git rev-parse --verify refs/heads/bogus
+'
+
++test_expect_success 'checkout --track=fetch warns and proceeds when fetch fails but ref exists' '
++ git checkout main &&
++ git -C fetch_upstream checkout -b fetch_offline &&
++ test_commit -C fetch_upstream u_offline &&
++ git fetch fetch_upstream fetch_offline &&
++ saved_url=$(git config remote.fetch_upstream.url) &&
++ test_when_finished "git config remote.fetch_upstream.url \"$saved_url\"" &&
++ git config remote.fetch_upstream.url ./does-not-exist &&
++ git checkout --track=fetch -b local_offline fetch_upstream/fetch_offline 2>err &&
++ test_grep "failed to fetch" err &&
++ test_cmp_rev refs/remotes/fetch_upstream/fetch_offline HEAD
++'
++
++test_expect_success 'checkout --track=fetch resolves through configured fetch refspec' '
++ git checkout main &&
++ git -C fetch_upstream checkout -b fetch_refspec &&
++ test_commit -C fetch_upstream u_refspec &&
++ git fetch fetch_upstream fetch_refspec &&
++ git remote add fetch_custom ./fetch_upstream &&
++ test_when_finished "git remote remove fetch_custom" &&
++ git config --replace-all remote.fetch_custom.fetch \
++ "+refs/heads/*:refs/remotes/custom-ns/*" &&
++ git fetch fetch_custom &&
++ test_commit -C fetch_upstream u_refspec_post &&
++ git checkout --track=fetch -b local_refspec custom-ns/fetch_refspec &&
++ test_cmp_rev refs/remotes/custom-ns/fetch_refspec HEAD
++'
++
++test_expect_success 'checkout --track=inherit,direct is rejected' '
++ test_must_fail git checkout --track=inherit,direct -b bad fetch_upstream/fetch_new 2>err &&
++ test_grep "cannot combine" err
++'
++
++test_expect_success 'checkout --track=fetch then --track=direct drops fetch (last-one-wins)' '
++ git checkout main &&
++ git -C fetch_upstream checkout -b fetch_lastwin &&
++ test_commit -C fetch_upstream u_lastwin &&
++ test_must_fail git rev-parse --verify refs/remotes/fetch_upstream/fetch_lastwin &&
++ test_must_fail git checkout --track=fetch --track=direct \
++ -b local_lastwin fetch_upstream/fetch_lastwin &&
++ test_must_fail git rev-parse --verify refs/remotes/fetch_upstream/fetch_lastwin
++'
++
+test_expect_success 'checkout --track=fetch,inherit fetches and inherits' '
+ git checkout main &&
+ git -C fetch_upstream checkout -b fetch_inherit &&
Documentation/git-checkout.adoc | 13 ++-
Documentation/git-switch.adoc | 13 ++-
builtin/checkout.c | 168 +++++++++++++++++++++++++++++++-
t/t7201-co.sh | 132 +++++++++++++++++++++++++
4 files changed, 319 insertions(+), 7 deletions(-)
diff --git a/Documentation/git-checkout.adoc b/Documentation/git-checkout.adoc
index 43ccf47cf6..28f17f427e 100644
--- a/Documentation/git-checkout.adoc
+++ b/Documentation/git-checkout.adoc
@@ -158,11 +158,22 @@ of it").
resets _<branch>_ to the start point instead of failing.
`-t`::
-`--track[=(direct|inherit)]`::
+`--track[=(direct|inherit|fetch)[,...]]`::
When creating a new branch, set up "upstream" configuration. See
`--track` in linkgit:git-branch[1] for details. As a convenience,
--track without -b implies branch creation.
+
+The argument is a comma-separated list. `direct` (the default) and
+`inherit` select the tracking mode and are mutually exclusive. Adding
+`fetch` requests that the remote be fetched before _<start-point>_ is
+resolved, so the new branch starts from a fresh tip: when
+_<start-point>_ is in _<remote>/<branch>_ form, only that branch is
+updated; when _<start-point>_ is a bare remote name (e.g. `origin`),
+only the remote's default branch is updated. If the fetch fails and the
+corresponding remote-tracking ref already exists, a warning is printed
+and the checkout proceeds from the existing tip; otherwise the checkout
+is aborted.
++
If no `-b` option is given, the name of the new branch will be
derived from the remote-tracking branch, by looking at the local part of
the refspec configured for the corresponding remote, and then stripping
diff --git a/Documentation/git-switch.adoc b/Documentation/git-switch.adoc
index 87707e9265..3f54cf39e9 100644
--- a/Documentation/git-switch.adoc
+++ b/Documentation/git-switch.adoc
@@ -154,11 +154,22 @@ should result in deletion of the path).
attached to a terminal, regardless of `--quiet`.
`-t`::
-`--track[ (direct|inherit)]`::
+`--track[=(direct|inherit|fetch)[,...]]`::
When creating a new branch, set up "upstream" configuration.
`-c` is implied. See `--track` in linkgit:git-branch[1] for
details.
+
+The argument is a comma-separated list. `direct` (the default) and
+`inherit` select the tracking mode and are mutually exclusive. Adding
+`fetch` requests that the remote be fetched before _<start-point>_ is
+resolved, so the new branch starts from a fresh tip: when
+_<start-point>_ is in _<remote>/<branch>_ form, only that branch is
+updated; when _<start-point>_ is a bare remote name (e.g. `origin`),
+only the remote's default branch is updated. If the fetch fails and the
+corresponding remote-tracking ref already exists, a warning is printed
+and the switch proceeds from the existing tip; otherwise the switch is
+aborted.
++
If no `-c` option is given, the name of the new branch will be derived
from the remote-tracking branch, by looking at the local part of the
refspec configured for the corresponding remote, and then stripping
diff --git a/builtin/checkout.c b/builtin/checkout.c
index e031e61886..8f8d1ecffe 100644
--- a/builtin/checkout.c
+++ b/builtin/checkout.c
@@ -26,11 +26,14 @@
#include "preload-index.h"
#include "read-cache.h"
#include "refs.h"
+#include "refspec.h"
#include "remote.h"
#include "repo-settings.h"
#include "resolve-undo.h"
#include "revision.h"
+#include "run-command.h"
#include "setup.h"
+#include "strvec.h"
#include "submodule.h"
#include "symlinks.h"
#include "trace2.h"
@@ -61,6 +64,7 @@ struct checkout_opts {
int count_checkout_paths;
int overlay_mode;
int dwim_new_local_branch;
+ int fetch;
int discard_changes;
int accept_ref;
int accept_pathspec;
@@ -112,6 +116,156 @@ struct branch_info {
char *checkout;
};
+static int resolve_fetch_target(const char *arg, char **remote_out,
+ char **src_ref_out)
+{
+ const char *slash;
+ char *remote_name;
+ struct remote *remote;
+ struct refspec_item query = { 0 };
+ struct strbuf dst = STRBUF_INIT;
+ const char *rest;
+
+ *remote_out = NULL;
+ *src_ref_out = NULL;
+
+ if (!arg || !*arg)
+ return -1;
+
+ slash = strchr(arg, '/');
+ if (slash == arg)
+ return -1;
+ remote_name = slash ? xstrndup(arg, slash - arg) : xstrdup(arg);
+
+ remote = remote_get(remote_name);
+ if (!remote || !remote_is_configured(remote, 1)) {
+ free(remote_name);
+ return -1;
+ }
+
+ rest = (slash && slash[1]) ? slash + 1 : NULL;
+ if (!rest) {
+ struct object_id oid;
+ const char *head_target;
+ const char *short_target;
+
+ strbuf_addf(&dst, "refs/remotes/%s/HEAD", remote_name);
+ head_target = refs_resolve_ref_unsafe(get_main_ref_store(the_repository),
+ dst.buf,
+ RESOLVE_REF_READING |
+ RESOLVE_REF_NO_RECURSE,
+ &oid, NULL);
+ strbuf_reset(&dst);
+ if (head_target &&
+ skip_prefix(head_target, "refs/remotes/", &short_target) &&
+ skip_prefix(short_target, remote_name, &short_target) &&
+ *short_target == '/')
+ rest = short_target + 1;
+ }
+
+ if (rest) {
+ strbuf_addf(&dst, "refs/remotes/%s/%s", remote_name, rest);
+ query.dst = dst.buf;
+ if (!remote_find_tracking(remote, &query) && query.src) {
+ *src_ref_out = xstrdup(query.src);
+ free(query.src);
+ } else {
+ *src_ref_out = xstrdup(rest);
+ }
+ }
+
+ strbuf_release(&dst);
+ *remote_out = remote_name;
+ return 0;
+}
+
+static void fetch_remote_for_start_point(const char *arg)
+{
+ char *remote_name = NULL;
+ char *src_ref = NULL;
+ struct child_process cmd = CHILD_PROCESS_INIT;
+ struct strbuf dst_ref = STRBUF_INIT;
+ int have_existing_ref = 0;
+
+ if (resolve_fetch_target(arg, &remote_name, &src_ref))
+ return;
+
+ if (src_ref) {
+ const char *short_src = src_ref;
+ struct object_id oid;
+
+ skip_prefix(short_src, "refs/heads/", &short_src);
+ strbuf_addf(&dst_ref, "refs/remotes/%s/%s", remote_name, short_src);
+ if (!refs_read_ref(get_main_ref_store(the_repository),
+ dst_ref.buf, &oid))
+ have_existing_ref = 1;
+ }
+
+ strvec_pushl(&cmd.args, "fetch", remote_name, NULL);
+ if (src_ref)
+ strvec_push(&cmd.args, src_ref);
+ cmd.git_cmd = 1;
+ if (run_command(&cmd)) {
+ if (have_existing_ref)
+ warning(_("failed to fetch start-point '%s'; "
+ "using existing '%s'"),
+ arg, dst_ref.buf);
+ else
+ die(_("failed to fetch start-point '%s'"), arg);
+ }
+
+ free(remote_name);
+ free(src_ref);
+ strbuf_release(&dst_ref);
+}
+
+static int parse_opt_checkout_track(const struct option *opt,
+ const char *arg, int unset)
+{
+ struct checkout_opts *opts = opt->value;
+ struct string_list tokens = STRING_LIST_INIT_DUP;
+ struct string_list_item *item;
+ int saw_direct = 0, saw_inherit = 0;
+ int ret = 0;
+
+ opts->fetch = 0;
+
+ if (unset) {
+ opts->track = BRANCH_TRACK_NEVER;
+ return 0;
+ }
+
+ opts->track = BRANCH_TRACK_EXPLICIT;
+ if (!arg)
+ return 0;
+
+ string_list_split(&tokens, arg, ",", -1);
+ for_each_string_list_item(item, &tokens) {
+ if (!strcmp(item->string, "fetch")) {
+ opts->fetch = 1;
+ } else if (!strcmp(item->string, "direct")) {
+ saw_direct = 1;
+ opts->track = BRANCH_TRACK_EXPLICIT;
+ } else if (!strcmp(item->string, "inherit")) {
+ saw_inherit = 1;
+ opts->track = BRANCH_TRACK_INHERIT;
+ } else {
+ ret = error(_("option `%s' expects \"%s\", \"%s\", "
+ "or \"%s\""),
+ "--track", "direct", "inherit", "fetch");
+ goto out;
+ }
+ }
+
+ if (saw_direct && saw_inherit)
+ ret = error(_("option `%s' cannot combine \"%s\" and \"%s\""),
+ "--track", "direct", "inherit");
+
+out:
+ string_list_clear(&tokens, 0);
+ return ret;
+}
+
static void branch_info_release(struct branch_info *info)
{
free(info->name);
@@ -1237,7 +1391,6 @@ static int git_checkout_config(const char *var, const char *value,
opts->dwim_new_local_branch = git_config_bool(var, value);
return 0;
}
-
if (starts_with(var, "submodule."))
return git_default_submodule_config(var, value, NULL);
@@ -1734,10 +1887,10 @@ static struct option *add_common_switch_branch_options(
{
struct option options[] = {
OPT_BOOL('d', "detach", &opts->force_detach, N_("detach HEAD at named commit")),
- OPT_CALLBACK_F('t', "track", &opts->track, "(direct|inherit)",
+ OPT_CALLBACK_F('t', "track", opts, "(direct|inherit|fetch)[,...]",
N_("set branch tracking configuration"),
PARSE_OPT_OPTARG,
- parse_opt_tracking_mode),
+ parse_opt_checkout_track),
OPT__FORCE(&opts->force, N_("force checkout (throw away local modifications)"),
PARSE_OPT_NOCOMPLETE),
OPT_STRING(0, "orphan", &opts->new_orphan_branch, N_("new-branch"), N_("new unborn branch")),
@@ -1942,8 +2095,13 @@ static int checkout_main(int argc, const char **argv, const char *prefix,
opts->dwim_new_local_branch &&
opts->track == BRANCH_TRACK_UNSPECIFIED &&
!opts->new_branch;
- int n = parse_branchname_arg(argc, argv, dwim_ok, which_command,
- &new_branch_info, opts, &rev);
+ int n;
+
+ if (opts->fetch)
+ fetch_remote_for_start_point(argv[0]);
+
+ n = parse_branchname_arg(argc, argv, dwim_ok, which_command,
+ &new_branch_info, opts, &rev);
argv += n;
argc -= n;
} else if (!opts->accept_ref && opts->from_treeish) {
diff --git a/t/t7201-co.sh b/t/t7201-co.sh
index 9bcf7c0b40..19ac6a1a2e 100755
--- a/t/t7201-co.sh
+++ b/t/t7201-co.sh
@@ -801,4 +801,136 @@ test_expect_success 'tracking info copied with autoSetupMerge=inherit' '
test_cmp_config "" --default "" branch.main2.merge
'
+test_expect_success 'setup upstream for --track=fetch tests' '
+ git checkout main &&
+ git init fetch_upstream &&
+ test_commit -C fetch_upstream u_main &&
+ git remote add fetch_upstream fetch_upstream &&
+ git fetch fetch_upstream &&
+ git -C fetch_upstream checkout -b fetch_new &&
+ test_commit -C fetch_upstream u_new
+'
+
+test_expect_success 'checkout --track=fetch -b picks up branch created upstream after clone' '
+ git checkout main &&
+ test_must_fail git rev-parse --verify refs/remotes/fetch_upstream/fetch_new &&
+ git checkout --track=fetch -b local_new fetch_upstream/fetch_new &&
+ test_cmp_rev refs/remotes/fetch_upstream/fetch_new HEAD &&
+ test_cmp_config fetch_upstream branch.local_new.remote &&
+ test_cmp_config refs/heads/fetch_new branch.local_new.merge
+'
+
+test_expect_success 'checkout --track=fetch <remote>/<branch> leaves other tracking branches untouched' '
+ git checkout main &&
+ git -C fetch_upstream checkout -b fetch_target &&
+ test_commit -C fetch_upstream u_target_pre &&
+ git -C fetch_upstream checkout -b fetch_other &&
+ test_commit -C fetch_upstream u_other_pre &&
+ git fetch fetch_upstream &&
+ other_before=$(git rev-parse refs/remotes/fetch_upstream/fetch_other) &&
+ git -C fetch_upstream checkout fetch_target &&
+ test_commit -C fetch_upstream u_target_post &&
+ git -C fetch_upstream checkout fetch_other &&
+ test_commit -C fetch_upstream u_other_post &&
+ git checkout --track=fetch -b local_target fetch_upstream/fetch_target &&
+ test_cmp_rev refs/remotes/fetch_upstream/fetch_target HEAD &&
+ test "$(git rev-parse refs/remotes/fetch_upstream/fetch_other)" = "$other_before"
+'
+
+test_expect_success 'checkout --track=fetch with bare remote name fetches only <remote>/HEAD target' '
+ git checkout main &&
+ git -C fetch_upstream checkout main &&
+ git remote set-head fetch_upstream main &&
+ git -C fetch_upstream checkout -b fetch_unrelated &&
+ test_commit -C fetch_upstream u_unrelated_pre &&
+ git fetch fetch_upstream fetch_unrelated &&
+ unrelated_before=$(git rev-parse refs/remotes/fetch_upstream/fetch_unrelated) &&
+ git -C fetch_upstream checkout main &&
+ test_commit -C fetch_upstream u_main_post &&
+ git -C fetch_upstream checkout fetch_unrelated &&
+ test_commit -C fetch_upstream u_unrelated_post &&
+ git checkout --track=fetch -b local_from_remote fetch_upstream &&
+ test_cmp_rev refs/remotes/fetch_upstream/main HEAD &&
+ test "$(git rev-parse refs/remotes/fetch_upstream/fetch_unrelated)" = "$unrelated_before"
+'
+
+test_expect_success 'checkout --track=fetch aborts and does not create branch when no existing ref' '
+ git checkout main &&
+ test_might_fail git branch -D bogus &&
+ test_must_fail git checkout --track=fetch -b bogus fetch_upstream/does_not_exist &&
+ test_must_fail git rev-parse --verify refs/heads/bogus
+'
+
+test_expect_success 'checkout --track=fetch warns and proceeds when fetch fails but ref exists' '
+ git checkout main &&
+ git -C fetch_upstream checkout -b fetch_offline &&
+ test_commit -C fetch_upstream u_offline &&
+ git fetch fetch_upstream fetch_offline &&
+ saved_url=$(git config remote.fetch_upstream.url) &&
+ test_when_finished "git config remote.fetch_upstream.url \"$saved_url\"" &&
+ git config remote.fetch_upstream.url ./does-not-exist &&
+ git checkout --track=fetch -b local_offline fetch_upstream/fetch_offline 2>err &&
+ test_grep "failed to fetch" err &&
+ test_cmp_rev refs/remotes/fetch_upstream/fetch_offline HEAD
+'
+
+test_expect_success 'checkout --track=fetch resolves through configured fetch refspec' '
+ git checkout main &&
+ git -C fetch_upstream checkout -b fetch_refspec &&
+ test_commit -C fetch_upstream u_refspec &&
+ git fetch fetch_upstream fetch_refspec &&
+ git remote add fetch_custom ./fetch_upstream &&
+ test_when_finished "git remote remove fetch_custom" &&
+ git config --replace-all remote.fetch_custom.fetch \
+ "+refs/heads/*:refs/remotes/custom-ns/*" &&
+ git fetch fetch_custom &&
+ test_commit -C fetch_upstream u_refspec_post &&
+ git checkout --track=fetch -b local_refspec custom-ns/fetch_refspec &&
+ test_cmp_rev refs/remotes/custom-ns/fetch_refspec HEAD
+'
+
+test_expect_success 'checkout --track=inherit,direct is rejected' '
+ test_must_fail git checkout --track=inherit,direct -b bad fetch_upstream/fetch_new 2>err &&
+ test_grep "cannot combine" err
+'
+
+test_expect_success 'checkout --track=fetch then --track=direct drops fetch (last-one-wins)' '
+ git checkout main &&
+ git -C fetch_upstream checkout -b fetch_lastwin &&
+ test_commit -C fetch_upstream u_lastwin &&
+ test_must_fail git rev-parse --verify refs/remotes/fetch_upstream/fetch_lastwin &&
+ test_must_fail git checkout --track=fetch --track=direct \
+ -b local_lastwin fetch_upstream/fetch_lastwin &&
+ test_must_fail git rev-parse --verify refs/remotes/fetch_upstream/fetch_lastwin
+'
+
+test_expect_success 'checkout --track=fetch,inherit fetches and inherits' '
+ git checkout main &&
+ git -C fetch_upstream checkout -b fetch_inherit &&
+ test_commit -C fetch_upstream u_inherit &&
+ git fetch fetch_upstream fetch_inherit &&
+ git checkout -b base_inherit fetch_upstream/fetch_inherit &&
+ test_commit -C fetch_upstream u_inherit2 &&
+ git checkout main &&
+ git checkout --track=fetch,inherit -b local_inherit base_inherit &&
+ test_cmp_rev refs/remotes/fetch_upstream/fetch_inherit HEAD &&
+ test_cmp_config fetch_upstream branch.local_inherit.remote &&
+ test_cmp_config refs/heads/fetch_inherit branch.local_inherit.merge
+'
+
+test_expect_success 'checkout --track=bogus reports an error' '
+ git checkout main &&
+ test_must_fail git checkout --track=bogus -b bogus_branch fetch_upstream/fetch_new 2>err &&
+ test_grep "expects" err
+'
+
+test_expect_success 'switch --track=fetch -c picks up branch created upstream after clone' '
+ git checkout main &&
+ git -C fetch_upstream checkout -b fetch_switch &&
+ test_commit -C fetch_upstream u_switch &&
+ test_must_fail git rev-parse --verify refs/remotes/fetch_upstream/fetch_switch &&
+ git switch --track=fetch -c local_switch fetch_upstream/fetch_switch &&
+ test_cmp_rev refs/remotes/fetch_upstream/fetch_switch HEAD
+'
+
test_done
base-commit: 94f057755b7941b321fd11fec1b2e3ca5313a4e0
--
gitgitgadget
^ permalink raw reply related
* [PATCH] daemon: fix network address handling bugs
From: Sebastien Tardif via GitGitGadget @ 2026-05-09 1:48 UTC (permalink / raw)
To: git; +Cc: Sebastien Tardif, Sebastien Tardif
From: Sebastien Tardif <sebtardif@ncf.ca>
Fix three related issues in daemon.c's network address handling:
lookup_hostname() calls getaddrinfo() with AF_UNSPEC hints, so it may
return IPv6 results. However, the code unconditionally casts ai_addr to
sockaddr_in and passes AF_INET to inet_ntop(). On IPv6-only hosts, this
reads from the wrong struct offset, producing garbage IP addresses. Fix
by checking ai_family and handling both AF_INET and AF_INET6.
ip2str() passes the sockaddr struct size (ai_addrlen) as the output
buffer size argument to inet_ntop(). For IPv6, sizeof(sockaddr_in6) is
28 bytes but INET6_ADDRSTRLEN is 46, so long IPv6 addresses are silently
truncated. Fix by passing sizeof(ip) instead, and drop the now-unused
len parameter.
execute() logs "Connection from %s:%s" using REMOTE_ADDR and
REMOTE_PORT environment variables, but only checks REMOTE_ADDR for NULL.
If REMOTE_PORT is unset, NULL is passed to printf's %s, which is
undefined behavior. Fix by using a fallback string.
Signed-off-by: Sebastien Tardif <sebtardif@ncf.ca>
---
daemon: fix network address handling bugs
Published-As: https://github.com/gitgitgadget/git/releases/tag/pr-git-2299%2FSebTardif%2Ffix%2Fdaemon-ipv6-and-null-port-v1
Fetch-It-Via: git fetch https://github.com/gitgitgadget/git pr-git-2299/SebTardif/fix/daemon-ipv6-and-null-port-v1
Pull-Request: https://github.com/git/git/pull/2299
daemon.c | 31 +++++++++++++++++++------------
1 file changed, 19 insertions(+), 12 deletions(-)
diff --git a/daemon.c b/daemon.c
index 0a7b1aae44..84a5e38f92 100644
--- a/daemon.c
+++ b/daemon.c
@@ -674,10 +674,17 @@ static void lookup_hostname(struct hostinfo *hi)
gai = getaddrinfo(hi->hostname.buf, NULL, &hints, &ai);
if (!gai) {
- struct sockaddr_in *sin_addr = (void *)ai->ai_addr;
-
- inet_ntop(AF_INET, &sin_addr->sin_addr,
- addrbuf, sizeof(addrbuf));
+ if (ai->ai_family == AF_INET) {
+ struct sockaddr_in *sa =
+ (struct sockaddr_in *)ai->ai_addr;
+ inet_ntop(AF_INET, &sa->sin_addr,
+ addrbuf, sizeof(addrbuf));
+ } else if (ai->ai_family == AF_INET6) {
+ struct sockaddr_in6 *sa6 =
+ (struct sockaddr_in6 *)ai->ai_addr;
+ inet_ntop(AF_INET6, &sa6->sin6_addr,
+ addrbuf, sizeof(addrbuf));
+ }
strbuf_addstr(&hi->ip_address, addrbuf);
if (ai->ai_canonname)
@@ -742,7 +749,7 @@ static int execute(void)
struct strvec env = STRVEC_INIT;
if (addr)
- loginfo("Connection from %s:%s", addr, port);
+ loginfo("Connection from %s:%s", addr, port ? port : "?");
set_keep_alive(0);
alarm(init_timeout ? init_timeout : timeout);
@@ -936,7 +943,7 @@ struct socketlist {
size_t alloc;
};
-static const char *ip2str(int family, struct sockaddr *sin, socklen_t len)
+static const char *ip2str(int family, struct sockaddr *sin)
{
#ifdef NO_IPV6
static char ip[INET_ADDRSTRLEN];
@@ -947,11 +954,11 @@ static const char *ip2str(int family, struct sockaddr *sin, socklen_t len)
switch (family) {
#ifndef NO_IPV6
case AF_INET6:
- inet_ntop(family, &((struct sockaddr_in6*)sin)->sin6_addr, ip, len);
+ inet_ntop(family, &((struct sockaddr_in6*)sin)->sin6_addr, ip, sizeof(ip));
break;
#endif
case AF_INET:
- inet_ntop(family, &((struct sockaddr_in*)sin)->sin_addr, ip, len);
+ inet_ntop(family, &((struct sockaddr_in*)sin)->sin_addr, ip, sizeof(ip));
break;
default:
xsnprintf(ip, sizeof(ip), "<unknown>");
@@ -1008,14 +1015,14 @@ static int setup_named_sock(char *listen_addr, int listen_port, struct socketlis
if (bind(sockfd, ai->ai_addr, ai->ai_addrlen) < 0) {
logerror("Could not bind to %s: %s",
- ip2str(ai->ai_family, ai->ai_addr, ai->ai_addrlen),
+ ip2str(ai->ai_family, ai->ai_addr),
strerror(errno));
close(sockfd);
continue; /* not fatal */
}
if (listen(sockfd, 5) < 0) {
logerror("Could not listen to %s: %s",
- ip2str(ai->ai_family, ai->ai_addr, ai->ai_addrlen),
+ ip2str(ai->ai_family, ai->ai_addr),
strerror(errno));
close(sockfd);
continue; /* not fatal */
@@ -1069,7 +1076,7 @@ static int setup_named_sock(char *listen_addr, int listen_port, struct socketlis
if ( bind(sockfd, (struct sockaddr *)&sin, sizeof sin) < 0 ) {
logerror("Could not bind to %s: %s",
- ip2str(AF_INET, (struct sockaddr *)&sin, sizeof(sin)),
+ ip2str(AF_INET, (struct sockaddr *)&sin),
strerror(errno));
close(sockfd);
return 0;
@@ -1077,7 +1084,7 @@ static int setup_named_sock(char *listen_addr, int listen_port, struct socketlis
if (listen(sockfd, 5) < 0) {
logerror("Could not listen to %s: %s",
- ip2str(AF_INET, (struct sockaddr *)&sin, sizeof(sin)),
+ ip2str(AF_INET, (struct sockaddr *)&sin),
strerror(errno));
close(sockfd);
return 0;
base-commit: 94f057755b7941b321fd11fec1b2e3ca5313a4e0
--
gitgitgadget
^ permalink raw reply related
* Re: [BUG] "git diff --word-diff" gives a diff while they are only space changes
From: Johannes Sixt @ 2026-05-09 6:16 UTC (permalink / raw)
To: Vincent Lefevre; +Cc: git
In-Reply-To: <20260508213943.GP5260@qaa.vinc17.org>
Am 08.05.26 um 23:39 schrieb Vincent Lefevre:
> On 2026-05-08 14:48:01 +0200, Johannes Sixt wrote:
>> This is expected behavior.
>>
>> git diff --word-diff is not agnostic to whitespace; if you drop
>> --word-diff, you see the line-diff that the word-diff is based on. If
>> you want whitespace-agnostic word-diff, you have to add -w.
>
> This is not how it is documented. Even when using "git diff" without
> --word-diff, but with GNU wdiff instead, the output is fine:
>
> $ git diff file1 file2 | wdiff -d
> diff --git a/file1 b/file2
> index da04344..0074613 100644
> [--- a/file1-]
> {+++ b/file2+}
> @@ -1,5 +1,5 @@
> 1
> 2
> 3
> 2
> 4
It would have helped if you had pointed to, or cited, the documentation.
I cannot find documentation from which I can derive that the above
*must* be the correct output. In particular, I don't find any mention
that --word-diff operates exactly like GNU wdiff.
-- Hannes
^ permalink raw reply
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