Re: [PATCH 1/2] lzma support: decompression lib, initrd support

Christian Leber
2005-06-13T23:45:59Z

On Mon, Jun 13, 2005 at 10:03:05PM +0200, Jesper Juhl wrote:

> Perhaps break
> up the lines a bit so it reads like normal C code instead of all this
> "multiple statements on one line", and there's lots of mixed-case usage,
> and I bet you could use inline functions...

Since when will inline functions render complex code in something easily
understandable?

> This #ifdef should be in col 0.

Renders code unreadable, but ok.

This patch is against 2.6.12-rc6.

This patch adds the possibility to compress a initrd with lzma, you
need ths CONFIG_BLK_DEV_RAM_LZMA build option to make use of lzma
compressed initrds.
(Device Drivers -> Block devices)

For example the debian installer initrd:
-rw-r--r-- 1 ijuz ijuz 2870355 Mar 5 20:00 initrd.gz
-rw-r--r-- 1 ijuz ijuz 2158769 May 8 02:09 initrd.lzma

Signed-off-by: Christian Leber <christian@leber.de>

--- linux-2.6.12-rc6.orig/init/do_mounts.h 2005-06-06 17:22:29.000000000 +0200
+++ linux-2.6.12-rc6/init/do_mounts.h 2005-06-13 23:54:40.000000000 +0200
@@ -90,3 +90,20 @@
static inline void md_run_setup(void) {}

#endif
+
+
+/*
+ * The following lines define some constants to support different
+ * compressed ramdisk types.
+ * Each compressed ramdisk type is bound to a _negative_ value,
+ * since positive values give us the number of blocks.
+ */
+
+#define RD_ERROR (-65535)
+#define CRAMDISK_LZMA (-1)
+#define CRAMDISK_GZ (-2)
+
+#if defined(CONFIG_BLK_DEV_RAM_GZ) || defined(CONFIG_BLK_DEV_RAM_LZMA)
+#define BUILD_CRAMDISK
+#endif
+
--- linux-2.6.12-rc6.orig/init/do_mounts_rd.c 2005-06-06 17:22:29.000000000 +0200
+++ linux-2.6.12-rc6/init/do_mounts_rd.c 2005-06-14 00:24:43.000000000 +0200
@@ -10,8 +10,6 @@

#include "do_mounts.h"

-#define BUILD_CRAMDISK
-
int __initdata rd_prompt = 1;/* 1 = prompt for RAM disk, 0 = don't prompt */

static int __init prompt_ramdisk(char *str)
@@ -30,20 +28,27 @@
}
__setup("ramdisk_start=", ramdisk_start_setup);

-static int __init crd_load(int in_fd, int out_fd);
+
+#ifdef CONFIG_BLK_DEV_RAM_GZ
+static int __init gz_load(int in_fd, int out_fd);
+#endif /* CONFIG_BLK_DEV_RAM_GZ */
+
+#ifdef CONFIG_BLK_DEV_RAM_LZMA
+static int __init lzma_load(int in_fd, int out_fd);
+#endif /* CONFIG_BLK_DEV_RAM_LZMA */

/*
* This routine tries to find a RAM disk image to load, and returns the
- * number of blocks to read for a non-compressed image, 0 if the image
- * is a compressed image, and -1 if an image with the right magic
- * numbers could not be found.
+ * number of blocks to read for a non-compressed image, a negative value
+ * if the image is a compressed image, and RD_ERROR if an image with
+ * the right magic numbers (see below) could not be found.
*
* We currently check for the following magic numbers:
* minix
* ext2
* romfs
* cramfs
- * gzip
+ * compressed image formats (gzip, lzma)
*/
static int __init
identify_ramdisk_image(int fd, int start_block)
@@ -53,12 +58,12 @@
struct ext2_super_block *ext2sb;
struct romfs_super_block *romfsb;
struct cramfs_super *cramfsb;
- int nblocks = -1;
+ int nblocks = RD_ERROR;
unsigned char *buf;

buf = kmalloc(size, GFP_KERNEL);
if (buf == 0)
- return -1;
+ return RD_ERROR;

minixsb = (struct minix_super_block *) buf;
ext2sb = (struct ext2_super_block *) buf;
@@ -73,16 +78,28 @@
sys_read(fd, buf, size);

/*
- * If it matches the gzip magic numbers, return -1
+ * If it matches the gzip magic numbers, return CRAMDISK_GZ
*/
if (buf[0] == 037 && ((buf[1] == 0213) || (buf[1] == 0236))) {
printk(KERN_NOTICE
- "RAMDISK: Compressed image found at block %d\n",
+ "RAMDISK: Gzip compressed image found at block %d\n",
start_block);
- nblocks = 0;
+ nblocks = CRAMDISK_GZ;
goto done;
}

+ /*
+ * Unfortunally lzma has no magic number, return CRAMDISK_LZMA
+ * but byte 9 to 12 has to be zero
+ */
+ if (buf[9] == 0 && buf[10] == 0 && buf[11] == 0 && buf[12] == 0) {
+ printk(KERN_NOTICE
+ "RAMDISK: lzma compressed image found at block %d\n",
+ start_block);
+ nblocks = CRAMDISK_LZMA;
+ goto done;
+ }
+
/* romfs is at block zero too */
if (romfsb->word0 == ROMSB_WORD0 &&
romfsb->word1 == ROMSB_WORD1) {
@@ -158,19 +175,27 @@
goto noclose_input;

nblocks = identify_ramdisk_image(in_fd, rd_image_start);
- if (nblocks < 0)
- goto done;
-
- if (nblocks == 0) {
-#ifdef BUILD_CRAMDISK
- if (crd_load(in_fd, out_fd) == 0)
- goto successful_load;
+ switch (nblocks) {
+ case CRAMDISK_LZMA : /* lzma image found */
+#ifdef CONFIG_BLK_DEV_RAM_LZMA
+ if (lzma_load(in_fd, out_fd) == 0)
+ goto successful_load;
#else
- printk(KERN_NOTICE
- "RAMDISK: Kernel does not support compressed "
- "RAM disk images\n");
+ printk(KERN_ALERT "RAMDISK: you don't have "
+ "CONFIG_BLK_DEV_RAM_LZMA\n");
#endif
- goto done;
+ break;
+ case CRAMDISK_GZ : /* gzip image found */
+#ifdef CONFIG_BLK_DEV_RAM_GZ
+ if (gz_load(in_fd, out_fd) == 0)
+ goto successful_load;
+#else
+ printk(KERN_ALERT "RAMDISK: you don't have "
+ "CONFIG_BLK_DEV_RAM_GZ\n");
+#endif
+ break;
+ default :
+ break;
}

/*
@@ -217,8 +242,9 @@
goto done;
}

- printk(KERN_NOTICE "RAMDISK: Loading %dKiB [%ld disk%s] into ram disk... ",
- nblocks, ((nblocks-1)/devblocks)+1, nblocks>devblocks ? "s" : "");
+ printk(KERN_NOTICE "RAMDISK: Loading %dKiB [%ld disk%s] into"
+ "ram disk... ", nblocks, ((nblocks-1)/devblocks)+1,
+ nblocks>devblocks ? "s" : "");
for (i = 0, disk = 1; i < nblocks; i++) {
if (i && (i % devblocks == 0)) {
printk("done disk #%d.\n", disk++);
@@ -254,7 +280,6 @@
sys_close(out_fd);
out:
kfree(buf);
- sys_unlink("/dev/ram");
return res;
}

@@ -267,7 +292,7 @@
return rd_load_image("/dev/root");
}

-#ifdef BUILD_CRAMDISK
+#ifdef CONFIG_BLK_DEV_RAM_GZ

/*
* gzip declarations
@@ -393,13 +418,13 @@
unzip_error = 1;
}

-static int __init crd_load(int in_fd, int out_fd)
+static int __init gz_load(int in_fd, int out_fd)
{
int result;

- insize = 0; /* valid bytes in inbuf */
- inptr = 0; /* index of next byte to be processed in inbuf */
- outcnt = 0; /* bytes in output buffer */
+ insize = 0; /* valid bytes in inbuf */
+ inptr = 0; /* index of next byte to be processed in inbuf */
+ outcnt = 0; /* bytes in output buffer */
exit_code = 0;
bytes_out = 0;
crc = (ulg)0xffffffffL; /* shift register contents */
@@ -426,4 +451,173 @@
return result;
}

-#endif /* BUILD_CRAMDISK */
+#endif /* ONFIG_BLK_DEV_RAM_GZ */
+
+#ifdef CONFIG_BLK_DEV_RAM_LZMA
+#include <linux/vmalloc.h>
+/* the lzma decompression function will use a callback function to get
+ * it's input data */
+#define _LZMA_IN_CB
+/* the lzma decompression function will only write out small pieces instead
+ * of everything to a single address, the disadvantage of this is that we
+ * need extra memory for the dictionary, the default size is 8 MB */
+#define _LZMA_OUT_READ
+#define _LZMA_READ_COMPRESSED_BUFFER_SIZE 0x10000
+#define _LZMA_WRITE_BUFFER_SIZE 0x10000
+
+#include <../lib/lzmadecode.h>
+#include <../lib/lzmadecode.c>
+
+typedef struct _cbuffer
+{
+ ILzmaInCallback in_callback;
+ unsigned char *buffer;
+ int lzma_read_fd;
+} cbuffer;
+
+static int lzma_read_in(void *obj, unsigned char **buffer, unsigned int *size)
+{
+ cbuffer *bo = obj;
+ int read_size;
+ /* try to read _LZMA_READ_COMPRESSED_BUFFER_SIZE bytes */
+ read_size = sys_read(bo->lzma_read_fd, bo->buffer,
+ _LZMA_READ_COMPRESSED_BUFFER_SIZE);
+ *size = read_size;
+ *buffer = bo->buffer;
+ return LZMA_RESULT_OK;
+}
+
+static int __init lzma_load(int in_fd, int out_fd)
+{
+ unsigned char properties[5], prop0;
+ unsigned char *dictionary, *out_buffer = 0;
+ unsigned int out_size, lzma_internal_size, size_processed;
+ unsigned int now_pos, dictionary_size = 0;
+ void *lzma_internal;
+ int lc, lp, pb;
+ int i, res, return_val;
+ cbuffer bo;
+
+ if (sys_read(in_fd, (unsigned char *)&properties, 5) == 0) {
+ printk(KERN_ERR "RAMDISK: ran out of compressed data\n");
+ return -1;
+ }
+
+ out_size = 0;
+ for (i = 0; i < 4; i++) {
+ unsigned char b;
+ if (sys_read(in_fd, &b, 1) == 0) {
+ printk(KERN_ERR "RAMDISK: ran out of compressed "
+ "data\n");
+ return -1;
+ }
+ out_size += (unsigned int)(b) << (i * 8);
+ }
+
+ for (i = 0; i < 4; i++) {
+ unsigned char b;
+ if (sys_read(in_fd, &b, 1) == 0) {
+ printk(KERN_ERR "RAMDISK: ran out of compressed "
+ "data\n");
+ return -1;
+ }
+ if (b!=0) {
+ printk(KERN_ERR "RAMDISK: either this is not a lzma"
+ "compressed ramdisk or it's bigger 4 GB\n");
+ return -1;
+ }
+ }
+
+ prop0 = properties[0];
+ if (prop0 >= (9*5*5)) {
+ printk(KERN_ERR "RAMDISK: lzma Properties error\n");
+ return -1;
+ }
+
+ pb = prop0 / 45;
+ prop0 = prop0 % 45;
+ lp = prop0 / 9;
+ lc = prop0 % 9;
+
+ lzma_internal_size = (LZMA_BASE_SIZE + (LZMA_LIT_SIZE << (lc + lp)))
+ * sizeof(CProb);
+ lzma_internal_size += 100; /* because we are using _LZMA_OUT_READ */
+
+ lzma_internal = vmalloc(lzma_internal_size);
+ if (lzma_internal == 0) {
+ printk(KERN_ERR "RAMDISK: failed to get memory "
+ "for lzma_internal\n");
+ return -1;
+ }
+
+ bo.in_callback.Read = lzma_read_in;
+ bo.lzma_read_fd = in_fd;
+ bo.buffer = vmalloc(_LZMA_READ_COMPRESSED_BUFFER_SIZE);
+ if (bo.buffer == 0) {
+ printk(KERN_ERR "RAMDISK: failed to get memory "
+ "for bo.buffer\n");
+ return_val = -1;
+ goto free_lzma_internal;
+ }
+
+ for (i = 0; i < 4; i++) {
+ dictionary_size += (u32)(properties[1 + i]) << (i * 8);
+ }
+ if (dictionary_size == 0) {
+ /* LZMA decoder can not work with dictionary_size = 0 */
+ dictionary_size = 1;
+ }
+ dictionary = vmalloc(dictionary_size);
+ if (dictionary == 0) {
+ printk(KERN_ERR "RAMDISK: failed to get memory "
+ "for dictionary\n");
+ return_val = -1;
+ goto free_bo_buffer;
+ }
+ res = LzmaDecoderInit((unsigned char *)lzma_internal,
+ lzma_internal_size,
+ lc, lp, pb,
+ dictionary, dictionary_size,
+ &bo.in_callback);
+ if (res == 0) {
+ out_buffer = vmalloc(_LZMA_WRITE_BUFFER_SIZE);
+ if (out_buffer == 0) {
+ printk(KERN_ERR "RAMDISK: failed to get memory"
+ "for out_buffer\n");
+ return_val = -1;
+ goto free_dictionary;
+ }
+ for (now_pos = 0; now_pos < out_size;) {
+ res = LzmaDecode((unsigned char *)lzma_internal,
+ out_buffer, _LZMA_WRITE_BUFFER_SIZE,
+ &size_processed);
+ if (res != 0)
+ break;
+ if (size_processed == 0) {
+ out_size = now_pos;
+ break;
+ }
+ now_pos += size_processed;
+ res = sys_write(out_fd, out_buffer, size_processed);
+ if (res != size_processed) {
+ printk(KERN_ERR "can't write everything,"
+ "the ramdisk is too small\n");
+ return_val = -1;
+ goto free_out_buffer;
+ }
+ }
+ }
+ return_val = 0;
+
+free_out_buffer:
+ vfree(out_buffer);
+free_dictionary:
+ vfree(dictionary);
+free_bo_buffer:
+ vfree(bo.buffer);
+free_lzma_internal:
+ vfree(lzma_internal);
+
+ return return_val;
+}
+#endif /* CONFIG_BLK_DEV_RAM_LZMA */
--- linux-2.6.12-rc6.orig/drivers/block/Kconfig 2005-06-06 17:22:29.000000000 +0200
+++ linux-2.6.12-rc6/drivers/block/Kconfig 2005-06-13 23:58:27.000000000 +0200
@@ -398,6 +398,41 @@
what are you doing. If you are using IBM S/390, then set this to
8192.

+config BLK_DEV_RAM_GZ
+ bool "Gzip compressed ramdisk support"
+ depends on BLK_DEV_RAM
+ default y
+ help
+ This option enables support for gzip compressed ramdisk images.
+ An image can be loaded as initrd (see above) or as a normal
+ ramdisk at boot time.
+ Enabling this option is good for people who use an initrd or
+ a normal ramdisk and who are low on available disk space.
+ The decompression process at boot time needs about 2 MB additional
+ RAM to the space the unpacked ramdisk needs.
+
+ Due to the fact that this feature is normally included in the
+ original ramdisk, you should say Y to this option.
+
+config BLK_DEV_RAM_LZMA
+ bool "Lzma compressed ramdisk support (EXPERIMENTAL)"
+ depends on BLK_DEV_RAM && EXPERIMENTAL
+ help
+ This option enables support for lzma compressed ramdisk images.
+ An image can be loaded as initrd (see above) or as a normal
+ ramdisk at boot time.
+ Enabling this option is good for people who use an initrd or
+ a normal ramdisk and who are very low on available disk space
+ (eg. for embedded systems with rom image and plenty of RAM).
+ This option was implemented, because lzma has better compression
+ than gzip. If you want to use this feature and disk space is a
+ matter, say N to gzip support and compress your ramdisk using
+ lzma.
+
+ This is an optional feature. Only enable this option if you need
+ lzma support for your ramdisk (e.g. for boot+root floppies or
+ business card rescue CDs). So if you are unsure say N.
+
config BLK_DEV_INITRD
bool "Initial RAM disk (initrd) support"
depends on BLK_DEV_RAM=y

--- linux-2.6.12-rc6.orig/lib/lzmadecode.h 1970-01-01 01:00:00.000000000 +0100
+++ linux-2.6.12-rc6/lib/lzmadecode.h 2005-06-14 01:23:31.000000000 +0200
@@ -0,0 +1,91 @@
+/*
+ LzmaDecode.h
+ LZMA Decoder interface
+
+ LZMA SDK 4.16 Copyright (c) 1999-2005 Igor Pavlov (2005-03-18)
+ http://www.7-zip.org/
+
+ LZMA SDK is licensed under two licenses:
+ 1) GNU Lesser General Public License (GNU LGPL)
+ 2) Common Public License (CPL)
+ It means that you can select one of these two licenses and
+ follow rules of that license.
+
+ SPECIAL EXCEPTION:
+ Igor Pavlov, as the author of this code, expressly permits you to
+ statically or dynamically link your code (or bind by name) to the
+ interfaces of this file without subjecting your linked code to the
+ terms of the CPL or GNU LGPL. Any modifications or additions
+ to this file, however, are subject to the LGPL or CPL terms.
+*/
+
+#ifndef __LZMADECODE_H
+#define __LZMADECODE_H
+
+/* #define _LZMA_IN_CB */
+/* Use callback for input data */
+
+/* #define _LZMA_OUT_READ */
+/* Use read function for output data */
+
+#define _LZMA_PROB32
+/* It can increase speed on some 32-bit CPUs,
+ but memory usage will be doubled in that case */
+
+#define _LZMA_LOC_OPT
+/* Enable local speed optimizations inside code */
+
+#ifdef _LZMA_PROB32
+#define CProb u32
+#else
+#define CProb unsigned short
+#endif
+
+#define LZMA_RESULT_OK 0
+#define LZMA_RESULT_DATA_ERROR 1
+#define LZMA_RESULT_NOT_ENOUGH_MEM 2
+
+#ifdef _LZMA_IN_CB
+typedef struct _ILzmaInCallback
+{
+ int (*Read)(void *object, unsigned char **buffer, u32 *bufferSize);
+} ILzmaInCallback;
+#endif
+
+#define LZMA_BASE_SIZE 1846
+#define LZMA_LIT_SIZE 768
+
+/*
+bufferSize = (LZMA_BASE_SIZE + (LZMA_LIT_SIZE << (lc + lp)))* sizeof(CProb)
+bufferSize += 100 in case of _LZMA_OUT_READ
+by default CProb is unsigned short,
+but if specify _LZMA_PROB_32, CProb will be u32(unsigned int)
+*/
+
+#ifdef _LZMA_OUT_READ
+int LzmaDecoderInit(
+ unsigned char *buffer, u32 bufferSize,
+ int lc, int lp, int pb,
+ unsigned char *dictionary, u32 dictionarySize,
+#ifdef _LZMA_IN_CB
+ ILzmaInCallback *inCallback
+#else
+ unsigned char *inStream, u32 inSize
+#endif /* _LZMA_IN_CB */
+);
+#endif /* _LZMA_OUT_READ */
+
+int LzmaDecode(
+ unsigned char *buffer,
+#ifndef _LZMA_OUT_READ
+ u32 bufferSize,
+ int lc, int lp, int pb,
+#ifdef _LZMA_IN_CB
+ ILzmaInCallback *inCallback,
+#else
+ unsigned char *inStream, u32 inSize,
+#endif /* _LZMA_IN_CB */
+#endif /* _LZMA_OUT_READ */
+ unsigned char *outStream, u32 outSize,
+ u32 *outSizeProcessed);
+#endif /* __LZMADECODE_H */
--- linux-2.6.12-rc6.orig/lib/lzmadecode.c 1970-01-01 01:00:00.000000000 +0100
+++ linux-2.6.12-rc6/lib/lzmadecode.c 2005-06-14 01:20:18.000000000 +0200
@@ -0,0 +1,542 @@
+/*
+ LZMA Decoder (optimized for Speed version)
+
+ LZMA SDK 4.17 Copyright (c) 1999-2005 Igor Pavlov (2005-04-05)
+http://www.7-zip.org/
+
+LZMA SDK is licensed under two licenses:
+1) GNU Lesser General Public License (GNU LGPL)
+2) Common Public License (CPL)
+It means that you can select one of these two licenses and
+follow rules of that license.
+
+SPECIAL EXCEPTION:
+Igor Pavlov, as the author of this Code, expressly permits you to
+statically or dynamically link your Code (or bind by name) to the
+interfaces of this file without subjecting your linked Code to the
+terms of the CPL or GNU LGPL. Any modifications or additions
+to this file, however, are subject to the LGPL or CPL terms.
+*/
+
+#include "lzmadecode.h"
+
+#define kNumTopBits 24
+#define kTopValue ((u32)1 << kNumTopBits)
+
+#define kNumBitModelTotalBits 11
+#define kBitModelTotal (1 << kNumBitModelTotalBits)
+#define kNumMoveBits 5
+
+#define RC_READ_BYTE (*Buffer++)
+
+#define RC_INIT2 Code = 0; range = 0xFFFFFFFF; \
+{ int i; for(i = 0; i < 5; i++) { RC_TEST; Code = (Code << 8) | RC_READ_BYTE; }}
+
+#ifdef _LZMA_IN_CB
+
+#define RC_TEST { if (Buffer == buffer_lim) \
+ { u32 size; int result = InCallback->Read(InCallback, &Buffer, &size); if (result != LZMA_RESULT_OK) return result; \
+ buffer_lim = Buffer + size; if (size == 0) return LZMA_RESULT_DATA_ERROR; }}
+
+#define RC_INIT Buffer = buffer_lim = 0; RC_INIT2
+
+#else
+
+#define RC_TEST { if (Buffer == buffer_lim) return LZMA_RESULT_DATA_ERROR; }
+
+#define RC_INIT(buffer, bufferSize) Buffer = buffer; buffer_lim = buffer + bufferSize; RC_INIT2
+
+#endif
+
+#define RC_NORMALIZE if (range < kTopValue) { RC_TEST; range <<= 8; Code = (Code << 8) | RC_READ_BYTE; }
+
+#define IfBit0(p) RC_NORMALIZE; bound = (range >> kNumBitModelTotalBits) * *(p); if (Code < bound)
+#define UpdateBit0(p) range = bound; *(p) += (kBitModelTotal - *(p)) >> kNumMoveBits;
+#define UpdateBit1(p) range -= bound; Code -= bound; *(p) -= (*(p)) >> kNumMoveBits;
+
+#define RC_GET_BIT2(p, mi, A0, A1) IfBit0(p) \
+{ UpdateBit0(p); mi <<= 1; A0; } else \
+{ UpdateBit1(p); mi = (mi + mi) + 1; A1; }
+
+#define RC_GET_BIT(p, mi) RC_GET_BIT2(p, mi, ; , ;)
+
+#define RangeDecoderBitTreeDecode(probs, numLevels, res) \
+{ int i = numLevels; res = 1; \
+ do { CProb *p = probs + res; RC_GET_BIT(p, res) } while(--i != 0); \
+ res -= (1 << numLevels); }
+
+
+#define kNumPosBitsMax 4
+#define kNumPosStatesMax (1 << kNumPosBitsMax)
+
+#define kLenNumLowBits 3
+#define kLenNumLowSymbols (1 << kLenNumLowBits)
+#define kLenNumMidBits 3
+#define kLenNumMidSymbols (1 << kLenNumMidBits)
+#define kLenNumHighBits 8
+#define kLenNumHighSymbols (1 << kLenNumHighBits)
+
+#define LenChoice 0
+#define LenChoice2 (LenChoice + 1)
+#define LenLow (LenChoice2 + 1)
+#define LenMid (LenLow + (kNumPosStatesMax << kLenNumLowBits))
+#define LenHigh (LenMid + (kNumPosStatesMax << kLenNumMidBits))
+#define kNumLenProbs (LenHigh + kLenNumHighSymbols)
+
+
+#define kNumStates 12
+#define kNumLitStates 7
+
+#define kStartPosModelIndex 4
+#define kEndPosModelIndex 14
+#define kNumFullDistances (1 << (kEndPosModelIndex >> 1))
+
+#define kNumPosSlotBits 6
+#define kNumLenToPosStates 4
+
+#define kNumAlignBits 4
+#define kAlignTableSize (1 << kNumAlignBits)
+
+#define kMatchMinLen 2
+
+#define IsMatch 0
+#define IsRep (IsMatch + (kNumStates << kNumPosBitsMax))
+#define IsRepG0 (IsRep + kNumStates)
+#define IsRepG1 (IsRepG0 + kNumStates)
+#define IsRepG2 (IsRepG1 + kNumStates)
+#define IsRep0Long (IsRepG2 + kNumStates)
+#define PosSlot (IsRep0Long + (kNumStates << kNumPosBitsMax))
+#define SpecPos (PosSlot + (kNumLenToPosStates << kNumPosSlotBits))
+#define Align (SpecPos + kNumFullDistances - kEndPosModelIndex)
+#define LenCoder (Align + kAlignTableSize)
+#define RepLenCoder (LenCoder + kNumLenProbs)
+#define Literal (RepLenCoder + kNumLenProbs)
+
+#if Literal != LZMA_BASE_SIZE
+#error StopCompilingDueBUG
+#endif
+
+#ifdef _LZMA_OUT_READ
+
+typedef struct _LzmaVarState
+{
+ unsigned char *Buffer;
+ unsigned char *buffer_lim;
+ u32 range;
+ u32 Code;
+#ifdef _LZMA_IN_CB
+ ILzmaInCallback *InCallback;
+#endif
+ unsigned char *Dictionary;
+ u32 dictionary_size;
+ u32 dictionary_pos;
+ u32 GlobalPos;
+ u32 Reps[4];
+ int lc;
+ int lp;
+ int pb;
+ int State;
+ int RemainLen;
+ unsigned char TempDictionary[4];
+} LzmaVarState;
+
+int LzmaDecoderInit(
+ unsigned char *buffer, u32 bufferSize,
+ int lc, int lp, int pb,
+ unsigned char *dictionary, u32 dictionarySize,
+#ifdef _LZMA_IN_CB
+ ILzmaInCallback *InCallback
+#else
+ unsigned char *inStream, u32 inSize
+#endif
+ )
+{
+ unsigned char *Buffer;
+ unsigned char *buffer_lim;
+ u32 range;
+ u32 Code;
+ LzmaVarState *vs = (LzmaVarState *)buffer;
+ CProb *p = (CProb *)(buffer + sizeof(LzmaVarState));
+ u32 numProbs = Literal + ((u32)LZMA_LIT_SIZE << (lc + lp));
+ u32 i;
+ if (bufferSize < numProbs * sizeof(CProb) + sizeof(LzmaVarState))
+ return LZMA_RESULT_NOT_ENOUGH_MEM;
+ vs->Dictionary = dictionary;
+ vs->dictionary_size = dictionarySize;
+ vs->dictionary_pos = 0;
+ vs->GlobalPos = 0;
+ vs->Reps[0] = vs->Reps[1] = vs->Reps[2] = vs->Reps[3] = 1;
+ vs->lc = lc;
+ vs->lp = lp;
+ vs->pb = pb;
+ vs->State = 0;
+ vs->RemainLen = 0;
+ dictionary[dictionarySize - 1] = 0;
+ for (i = 0; i < numProbs; i++)
+ p[i] = kBitModelTotal >> 1;
+
+#ifdef _LZMA_IN_CB
+ RC_INIT;
+#else
+ RC_INIT(inStream, inSize);
+#endif /* _LZMA_IN_CB */
+ vs->Buffer = Buffer;
+ vs->buffer_lim = buffer_lim;
+ vs->range = range;
+ vs->Code = Code;
+#ifdef _LZMA_IN_CB
+ vs->InCallback = InCallback;
+#endif
+
+ return LZMA_RESULT_OK;
+}
+
+int LzmaDecode(unsigned char *buffer,
+ unsigned char *outStream, u32 outSize,
+ u32 *outSizeProcessed)
+{
+ LzmaVarState *vs = (LzmaVarState *)buffer;
+ unsigned char *Buffer = vs->Buffer;
+ unsigned char *buffer_lim = vs->buffer_lim;
+ u32 range = vs->range;
+ u32 Code = vs->Code;
+#ifdef _LZMA_IN_CB
+ ILzmaInCallback *InCallback = vs->InCallback;
+#endif
+ CProb *p = (CProb *)(buffer + sizeof(LzmaVarState));
+ int state = vs->State;
+ unsigned char previousByte;
+ u32 rep0 = vs->Reps[0], rep1 = vs->Reps[1];
+ u32 rep2 = vs->Reps[2], rep3 = vs->Reps[3];
+ u32 nowPos = 0;
+ u32 posStateMask = (1 << (vs->pb)) - 1;
+ u32 literalPosMask = (1 << (vs->lp)) - 1;
+ int lc = vs->lc;
+ int len = vs->RemainLen;
+ u32 globalPos = vs->GlobalPos;
+
+ unsigned char *dictionary = vs->Dictionary;
+ u32 dictionarySize = vs->dictionary_size;
+ u32 dictionaryPos = vs->dictionary_pos;
+
+ unsigned char tempDictionary[4];
+ if (dictionarySize == 0) {
+ dictionary = tempDictionary;
+ dictionarySize = 1;
+ tempDictionary[0] = vs->TempDictionary[0];
+ }
+
+ if (len == -1) {
+ *outSizeProcessed = 0;
+ return LZMA_RESULT_OK;
+ }
+
+ while(len != 0 && nowPos < outSize) {
+ u32 pos = dictionaryPos - rep0;
+ if (pos >= dictionarySize)
+ pos += dictionarySize;
+ outStream[nowPos++] = dictionary[dictionaryPos] =
+ dictionary[pos];
+ if (++dictionaryPos == dictionarySize)
+ dictionaryPos = 0;
+ len--;
+ }
+ if (dictionaryPos == 0)
+ previousByte = dictionary[dictionarySize - 1];
+ else
+ previousByte = dictionary[dictionaryPos - 1];
+#else /*_LZMA_OUT_READ */
+
+int LzmaDecode(
+ unsigned char *buffer, u32 bufferSize,
+ int lc, int lp, int pb,
+#ifdef _LZMA_IN_CB
+ ILzmaInCallback *InCallback,
+#else
+ unsigned char *inStream, u32 inSize,
+#endif
+ unsigned char *outStream, u32 outSize,
+ u32 *outSizeProcessed)
+{
+ u32 numProbs = Literal + ((u32)LZMA_LIT_SIZE << (lc + lp));
+ CProb *p = (CProb *)buffer;
+
+ u32 i;
+ int state = 0;
+ unsigned char previousByte = 0;
+ u32 rep0 = 1, rep1 = 1, rep2 = 1, rep3 = 1;
+ u32 nowPos = 0;
+ u32 posStateMask = (1 << pb) - 1;
+ u32 literalPosMask = (1 << lp) - 1;
+ int len = 0;
+
+ unsigned char *Buffer;
+ unsigned char *buffer_lim;
+ u32 range;
+ u32 Code;
+
+ if (bufferSize < numProbs * sizeof(CProb))
+ return LZMA_RESULT_NOT_ENOUGH_MEM;
+ for (i = 0; i < numProbs; i++)
+ p[i] = kBitModelTotal >> 1;
+
+
+#ifdef _LZMA_IN_CB
+ RC_INIT;
+#else
+ RC_INIT(inStream, inSize);
+#endif
+#endif
+
+ *outSizeProcessed = 0;
+ while(nowPos < outSize) {
+ CProb *prob;
+ u32 bound;
+ int posState = (int)(
+ (nowPos
+#ifdef _LZMA_OUT_READ
+ + globalPos
+#endif
+ )
+ & posStateMask);
+
+ prob = p + IsMatch + (state << kNumPosBitsMax)
+ + posState;
+ IfBit0(prob) {
+ int symbol = 1;
+ UpdateBit0(prob)
+ prob = p + Literal + (LZMA_LIT_SIZE *
+ (((
+ (nowPos
+#ifdef _LZMA_OUT_READ
+ + globalPos
+#endif
+ )
+ & literalPosMask) << lc) + (previousByte >> (8 - lc))));
+
+ if (state >= kNumLitStates) {
+ int matchByte;
+#ifdef _LZMA_OUT_READ
+ u32 pos = dictionaryPos - rep0;
+ if (pos >= dictionarySize)
+ pos += dictionarySize;
+ matchByte = dictionary[pos];
+#else
+ matchByte = outStream[nowPos - rep0];
+#endif
+ do {
+ int bit;
+ CProb *probLit;
+ matchByte <<= 1;
+ bit = (matchByte & 0x100);
+ probLit = prob + 0x100 + bit + symbol;
+ RC_GET_BIT2(probLit, symbol, if (bit != 0) break, if (bit == 0) break)
+ } while (symbol < 0x100);
+ }
+ while (symbol < 0x100) {
+ CProb *probLit = prob + symbol;
+ RC_GET_BIT(probLit, symbol)
+ }
+ previousByte = (unsigned char)symbol;
+
+ outStream[nowPos++] = previousByte;
+#ifdef _LZMA_OUT_READ
+ dictionary[dictionaryPos] = previousByte;
+ if (++dictionaryPos == dictionarySize)
+ dictionaryPos = 0;
+#endif
+ if (state < 4) state = 0;
+ else if (state < 10) state -= 3;
+ else state -= 6;
+ } else {
+ UpdateBit1(prob);
+ prob = p + IsRep + state;
+ IfBit0(prob) {
+ UpdateBit0(prob);
+ rep3 = rep2;
+ rep2 = rep1;
+ rep1 = rep0;
+ state = state < kNumLitStates ? 0 : 3;
+ prob = p + LenCoder;
+ } else {
+ UpdateBit1(prob);
+ prob = p + IsRepG0 + state;
+ IfBit0(prob) {
+ UpdateBit0(prob);
+ prob = p + IsRep0Long + (state << kNumPosBitsMax) + posState;
+ IfBit0(prob) {
+#ifdef _LZMA_OUT_READ
+ u32 pos;
+#endif
+ UpdateBit0(prob);
+ if (nowPos
+#ifdef _LZMA_OUT_READ
+ + globalPos
+#endif
+ == 0)
+ return LZMA_RESULT_DATA_ERROR;
+ state = state < kNumLitStates ? 9 : 11;
+#ifdef _LZMA_OUT_READ
+ pos = dictionaryPos - rep0;
+ if (pos >= dictionarySize)
+ pos += dictionarySize;
+ previousByte = dictionary[pos];
+ dictionary[dictionaryPos] = previousByte;
+ if (++dictionaryPos == dictionarySize)
+ dictionaryPos = 0;
+#else
+ previousByte = outStream[nowPos - rep0];
+#endif
+ outStream[nowPos++] = previousByte;
+ continue;
+ } else {
+ UpdateBit1(prob);
+ }
+ } else {
+ u32 distance;
+ UpdateBit1(prob);
+ prob = p + IsRepG1 + state;
+ IfBit0(prob) {
+ UpdateBit0(prob);
+ distance = rep1;
+ } else {
+ UpdateBit1(prob);
+ prob = p + IsRepG2 + state;
+ IfBit0(prob) {
+ UpdateBit0(prob);
+ distance = rep2;
+ } else {
+ UpdateBit1(prob);
+ distance = rep3;
+ rep3 = rep2;
+ }
+ rep2 = rep1;
+ }
+ rep1 = rep0;
+ rep0 = distance;
+ }
+ state = state < kNumLitStates ? 8 : 11;
+ prob = p + RepLenCoder;
+ }
+
+ {
+ int numBits, offset;
+ CProb *probLen = prob + LenChoice;
+ IfBit0(probLen) {
+ UpdateBit0(probLen);
+ probLen = prob + LenLow + (posState << kLenNumLowBits);
+ offset = 0;
+ numBits = kLenNumLowBits;
+ } else {
+ UpdateBit1(probLen);
+ probLen = prob + LenChoice2;
+ IfBit0(probLen) {
+ UpdateBit0(probLen);
+ probLen = prob + LenMid + (posState << kLenNumMidBits);
+ offset = kLenNumLowSymbols;
+ numBits = kLenNumMidBits;
+ } else {
+ UpdateBit1(probLen);
+ probLen = prob + LenHigh;
+ offset = kLenNumLowSymbols + kLenNumMidSymbols;
+ numBits = kLenNumHighBits;
+ }
+ }
+ RangeDecoderBitTreeDecode(probLen, numBits, len);
+ len += offset;
+ }
+
+ if (state < 4) {
+ int posSlot;
+ state += kNumLitStates;
+ prob = p + PosSlot +
+ ((len < kNumLenToPosStates ? len : kNumLenToPosStates - 1) <<
+ kNumPosSlotBits);
+ RangeDecoderBitTreeDecode(prob, kNumPosSlotBits, posSlot);
+ if (posSlot >= kStartPosModelIndex) {
+ int numDirectBits = ((posSlot >> 1) - 1);
+ rep0 = (2 | ((u32)posSlot & 1));
+ if (posSlot < kEndPosModelIndex) {
+ rep0 <<= numDirectBits;
+ prob = p + SpecPos + rep0 - posSlot - 1;
+ } else {
+ numDirectBits -= kNumAlignBits;
+ do {
+ RC_NORMALIZE
+ range >>= 1;
+ rep0 <<= 1;
+ if (Code >= range) {
+ Code -= range;
+ rep0 |= 1;
+ }
+ } while (--numDirectBits != 0);
+ prob = p + Align;
+ rep0 <<= kNumAlignBits;
+ numDirectBits = kNumAlignBits;
+ }
+ {
+ int i = 1;
+ int mi = 1;
+ do {
+ CProb *prob3 = prob + mi;
+ RC_GET_BIT2(prob3, mi, ; , rep0 |= i);
+ i <<= 1;
+ } while(--numDirectBits != 0);
+ }
+ } else {
+ rep0 = posSlot;
+ }
+ if (++rep0 == (u32)(0)) {
+ /* it's for stream version */
+ len = -1;
+ break;
+ }
+ }
+
+ len += kMatchMinLen;
+ if (rep0 > nowPos
+#ifdef _LZMA_OUT_READ
+ + globalPos || rep0 > dictionarySize
+#endif
+ )
+ return LZMA_RESULT_DATA_ERROR;
+ do
+ {
+#ifdef _LZMA_OUT_READ
+ u32 pos = dictionaryPos - rep0;
+ if (pos >= dictionarySize)
+ pos += dictionarySize;
+ previousByte = dictionary[pos];
+ dictionary[dictionaryPos] = previousByte;
+ if (++dictionaryPos == dictionarySize)
+ dictionaryPos = 0;
+#else
+ previousByte = outStream[nowPos - rep0];
+#endif
+ len--;
+ outStream[nowPos++] = previousByte;
+ }
+ while(len != 0 && nowPos < outSize);
+ }
+ }
+ RC_NORMALIZE;
+
+#ifdef _LZMA_OUT_READ
+ vs->Buffer = Buffer;
+ vs->buffer_lim = buffer_lim;
+ vs->range = range;
+ vs->Code = Code;
+ vs->dictionary_pos = dictionaryPos;
+ vs->GlobalPos = globalPos + nowPos;
+ vs->Reps[0] = rep0;
+ vs->Reps[1] = rep1;
+ vs->Reps[2] = rep2;
+ vs->Reps[3] = rep3;
+ vs->State = state;
+ vs->RemainLen = len;
+ vs->TempDictionary[0] = tempDictionary[0];
+#endif /* _LZMA_OUT_READ */
+
+ *outSizeProcessed = nowPos;
+ return LZMA_RESULT_OK;
+}

--