From: "Johannes Schindelin via GitGitGadget" <gitgitgadget@gmail.com>
To: git@vger.kernel.org
Cc: Patrick Steinhardt <ps@pks.im>,
Johannes Schindelin <johannes.schindelin@gmx.de>,
Johannes Schindelin <johannes.schindelin@gmx.de>
Subject: [PATCH v3 4/6] to be squashed into 3/6 (chunk 1 of 3)
Date: Fri, 08 May 2026 12:50:59 +0000 [thread overview]
Message-ID: <9085f009107cf7ca2c7e92fb89d111daf0e30783.1778244661.git.gitgitgadget@gmail.com> (raw)
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
next prev parent reply other threads:[~2026-05-08 12:51 UTC|newest]
Thread overview: 20+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-05-03 12:29 [PATCH] mingw: stop using nedmalloc Johannes Schindelin via GitGitGadget
2026-05-05 6:09 ` Patrick Steinhardt
2026-05-07 16:00 ` [PATCH v2 0/6] " Johannes Schindelin via GitGitGadget
2026-05-07 16:00 ` [PATCH v2 1/6] " Johannes Schindelin via GitGitGadget
2026-05-07 16:00 ` [PATCH v2 2/6] mingw: drop the build-system plumbing for nedmalloc Johannes Schindelin via GitGitGadget
2026-05-07 16:00 ` [PATCH v2 3/6] mingw: drop the small nedmalloc auxiliary files Johannes Schindelin via GitGitGadget
2026-05-07 16:00 ` [PATCH v2 4/6] mingw: drop the first chunk of compat/nedmalloc/malloc.c.h Johannes Schindelin via GitGitGadget
2026-05-07 16:00 ` [PATCH v2 5/6] mingw: drop the second " Johannes Schindelin via GitGitGadget
2026-05-07 16:00 ` [PATCH v2 6/6] mingw: drop the rest " Johannes Schindelin via GitGitGadget
2026-05-08 2:56 ` [PATCH v2 0/6] mingw: stop using nedmalloc Junio C Hamano
2026-05-08 14:15 ` Jeff King
2026-05-08 12:50 ` [PATCH v3 " Johannes Schindelin via GitGitGadget
2026-05-08 12:50 ` [PATCH v3 1/6] " Johannes Schindelin via GitGitGadget
2026-05-08 12:50 ` [PATCH v3 2/6] mingw: drop the build-system plumbing for nedmalloc Johannes Schindelin via GitGitGadget
2026-05-08 12:50 ` [PATCH v3 3/6] mingw: remove the vendored compat/nedmalloc/ subtree Johannes Schindelin via GitGitGadget
2026-05-08 12:50 ` Johannes Schindelin via GitGitGadget [this message]
2026-05-08 12:51 ` [PATCH v3 5/6] to be squashed into 3/6 (chunk 2 of 3) Johannes Schindelin via GitGitGadget
2026-05-08 12:51 ` [PATCH v3 6/6] to be squashed into 3/6 (chunk 3 " Johannes Schindelin via GitGitGadget
2026-05-08 13:17 ` [PATCH v3 0/6] mingw: stop using nedmalloc Patrick Steinhardt
2026-05-10 2:31 ` Junio C Hamano
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