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[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index] [Xen-devel] [PATCH] x86/dom0: support bzip2 and lzma compressed bzImage payloads
This matches functionality in the tools already supporting the same for
DomU-s.
Code taken from Linux 2.6.32-rc and adjusted as little as possible to
be usable in Xen.
The question is whether, particularly for non-Linux Dom0-s, plain ELF
images compressed by bzip2 or lzma should also be supported.
Signed-off-by: Jan Beulich <jbeulich@xxxxxxxxxx>
--- 2009-10-27.orig/xen/arch/x86/bzimage.c 2009-10-07 13:31:36.000000000
+0200
+++ 2009-10-27/xen/arch/x86/bzimage.c 2009-11-05 12:23:05.000000000 +0100
@@ -4,6 +4,7 @@
#include <xen/mm.h>
#include <xen/string.h>
#include <xen/types.h>
+#include <xen/decompress.h>
#include <asm/bzimage.h>
#define HEAPORDER 3
@@ -93,28 +94,38 @@ static __init void flush_window(void)
outcnt = 0;
}
-static __init int gzip_length(char *image, unsigned long image_len)
+static __init unsigned long output_length(char *image, unsigned long image_len)
{
return *(uint32_t *)&image[image_len - 4];
}
-static __init int perform_gunzip(char *output, char **_image_start, unsigned
long *image_len)
+static __init int gzip_check(char *image, unsigned long image_len)
{
- char *image = *_image_start;
- int rc;
- unsigned char magic0 = (unsigned char)image[0];
- unsigned char magic1 = (unsigned char)image[1];
+ unsigned char magic0, magic1;
- if ( magic0 != 0x1f || ( (magic1 != 0x8b) && (magic1 != 0x9e) ) )
+ if ( image_len < 2 )
return 0;
+ magic0 = (unsigned char)image[0];
+ magic1 = (unsigned char)image[1];
+
+ return (magic0 == 0x1f) && ((magic1 == 0x8b) || (magic1 == 0x9e));
+}
+
+static __init int perform_gunzip(char *output, char *image, unsigned long
image_len)
+{
+ int rc;
+
+ if ( !gzip_check(image, image_len) )
+ return 1;
+
window = (unsigned char *)output;
free_mem_ptr = (unsigned long)alloc_xenheap_pages(HEAPORDER, 0);
free_mem_end_ptr = free_mem_ptr + (PAGE_SIZE << HEAPORDER);
inbuf = (unsigned char *)image;
- insize = *image_len;
+ insize = image_len;
inptr = 0;
makecrc();
@@ -125,8 +136,6 @@ static __init int perform_gunzip(char *
}
else
{
- *_image_start = (char *)window;
- *image_len = gzip_length(image, *image_len);
rc = 0;
}
@@ -203,9 +212,12 @@ int __init bzimage_headroom(char *image_
img = image_start + (hdr->setup_sects+1) * 512;
img += hdr->payload_offset;
- headroom = gzip_length(img, hdr->payload_length);
- headroom += headroom >> 12; /* Add 8 bytes for every 32K input block */
- headroom += (32768 + 18); /* Add 32K + 18 bytes of extra headroom */
+ headroom = output_length(img, hdr->payload_length);
+ if (gzip_check(img, hdr->payload_length)) {
+ headroom += headroom >> 12; /* Add 8 bytes for every 32K input block */
+ headroom += (32768 + 18); /* Add 32K + 18 bytes of extra headroom */
+ } else
+ headroom += hdr->payload_length;
headroom = (headroom + 4095) & ~4095;
return headroom;
@@ -215,6 +227,7 @@ int __init bzimage_parse(char *image_bas
{
struct setup_header *hdr = (struct setup_header *)(*image_start);
int err = bzimage_check(hdr, *image_len);
+ unsigned long output_len;
if (err < 1)
return err;
@@ -224,11 +237,18 @@ int __init bzimage_parse(char *image_bas
*image_start += (hdr->setup_sects+1) * 512;
*image_start += hdr->payload_offset;
*image_len = hdr->payload_length;
+ output_len = output_length(*image_start, *image_len);
- if ( (err = perform_gunzip(image_base, image_start, image_len)) < 0 )
- return err;
+ if ( (err = perform_gunzip(image_base, *image_start, *image_len)) > 0 )
+ err = decompress(*image_start, *image_len, image_base);
+
+ if ( !err )
+ {
+ *image_start = image_base;
+ *image_len = output_len;
+ }
- return 0;
+ return err > 0 ? 0 : err;
}
/*
--- 2009-10-27.orig/xen/common/Makefile 2009-05-27 13:54:07.000000000 +0200
+++ 2009-10-27/xen/common/Makefile 2009-11-05 12:26:53.000000000 +0100
@@ -35,6 +35,8 @@ obj-y += radix-tree.o
obj-y += rbtree.o
obj-y += lzo.o
+obj-$(CONFIG_X86) += decompress.o bunzip2.o unlzma.o
+
obj-$(perfc) += perfc.o
obj-$(crash_debug) += gdbstub.o
obj-$(xenoprof) += xenoprof.o
--- /dev/null 1970-01-01 00:00:00.000000000 +0000
+++ 2009-10-27/xen/common/bunzip2.c 2009-11-05 12:44:51.000000000 +0100
@@ -0,0 +1,726 @@
+/* vi: set sw = 4 ts = 4: */
+/* Small bzip2 deflate implementation, by Rob Landley (rob@xxxxxxxxxxx).
+
+ Based on bzip2 decompression code by Julian R Seward (jseward@xxxxxxx),
+ which also acknowledges contributions by Mike Burrows, David Wheeler,
+ Peter Fenwick, Alistair Moffat, Radford Neal, Ian H. Witten,
+ Robert Sedgewick, and Jon L. Bentley.
+
+ This code is licensed under the LGPLv2:
+ LGPL (http://www.gnu.org/copyleft/lgpl.html
+*/
+
+/*
+ Size and speed optimizations by Manuel Novoa III (mjn3@xxxxxxxxxxxx).
+
+ More efficient reading of Huffman codes, a streamlined read_bunzip()
+ function, and various other tweaks. In (limited) tests, approximately
+ 20% faster than bzcat on x86 and about 10% faster on arm.
+
+ Note that about 2/3 of the time is spent in read_unzip() reversing
+ the Burrows-Wheeler transformation. Much of that time is delay
+ resulting from cache misses.
+
+ I would ask that anyone benefiting from this work, especially those
+ using it in commercial products, consider making a donation to my local
+ non-profit hospice organization in the name of the woman I loved, who
+ passed away Feb. 12, 2003.
+
+ In memory of Toni W. Hagan
+
+ Hospice of Acadiana, Inc.
+ 2600 Johnston St., Suite 200
+ Lafayette, LA 70503-3240
+
+ Phone (337) 232-1234 or 1-800-738-2226
+ Fax (337) 232-1297
+
+ http://www.hospiceacadiana.com/
+
+ Manuel
+ */
+
+/*
+ Made it fit for running in Linux Kernel by Alain Knaff (alain@xxxxxxxx)
+*/
+
+#include "decompress.h"
+
+#ifndef INT_MAX
+#define INT_MAX 0x7fffffff
+#endif
+
+/* Constants for Huffman coding */
+#define MAX_GROUPS 6
+#define GROUP_SIZE 50 /* 64 would have been more efficient */
+#define MAX_HUFCODE_BITS 20 /* Longest Huffman code allowed */
+#define MAX_SYMBOLS 258 /* 256 literals + RUNA + RUNB */
+#define SYMBOL_RUNA 0
+#define SYMBOL_RUNB 1
+
+/* Status return values */
+#define RETVAL_OK 0
+#define RETVAL_LAST_BLOCK (-1)
+#define RETVAL_NOT_BZIP_DATA (-2)
+#define RETVAL_UNEXPECTED_INPUT_EOF (-3)
+#define RETVAL_UNEXPECTED_OUTPUT_EOF (-4)
+#define RETVAL_DATA_ERROR (-5)
+#define RETVAL_OUT_OF_MEMORY (-6)
+#define RETVAL_OBSOLETE_INPUT (-7)
+
+/* Other housekeeping constants */
+#define BZIP2_IOBUF_SIZE 4096
+
+/* This is what we know about each Huffman coding group */
+struct group_data {
+ /* We have an extra slot at the end of limit[] for a sentinal value. */
+ int limit[MAX_HUFCODE_BITS+1];
+ int base[MAX_HUFCODE_BITS];
+ int permute[MAX_SYMBOLS];
+ int minLen, maxLen;
+};
+
+/* Structure holding all the housekeeping data, including IO buffers and
+ memory that persists between calls to bunzip */
+struct bunzip_data {
+ /* State for interrupting output loop */
+ int writeCopies, writePos, writeRunCountdown, writeCount, writeCurrent;
+ /* I/O tracking data (file handles, buffers, positions, etc.) */
+ int (*fill)(void*, unsigned int);
+ int inbufCount, inbufPos /*, outbufPos*/;
+ unsigned char *inbuf /*,*outbuf*/;
+ unsigned int inbufBitCount, inbufBits;
+ /* The CRC values stored in the block header and calculated from the
+ data */
+ unsigned int crc32Table[256], headerCRC, totalCRC, writeCRC;
+ /* Intermediate buffer and its size (in bytes) */
+ unsigned int *dbuf, dbufSize;
+ /* These things are a bit too big to go on the stack */
+ unsigned char selectors[32768]; /* nSelectors = 15 bits */
+ struct group_data groups[MAX_GROUPS]; /* Huffman coding tables */
+ int io_error; /* non-zero if we have IO error */
+};
+
+
+/* Return the next nnn bits of input. All reads from the compressed input
+ are done through this function. All reads are big endian */
+static unsigned int INIT get_bits(struct bunzip_data *bd, char bits_wanted)
+{
+ unsigned int bits = 0;
+
+ /* If we need to get more data from the byte buffer, do so.
+ (Loop getting one byte at a time to enforce endianness and avoid
+ unaligned access.) */
+ while (bd->inbufBitCount < bits_wanted) {
+ /* If we need to read more data from file into byte buffer, do
+ so */
+ if (bd->inbufPos == bd->inbufCount) {
+ if (bd->io_error)
+ return 0;
+ bd->inbufCount = bd->fill(bd->inbuf, BZIP2_IOBUF_SIZE);
+ if (bd->inbufCount <= 0) {
+ bd->io_error = RETVAL_UNEXPECTED_INPUT_EOF;
+ return 0;
+ }
+ bd->inbufPos = 0;
+ }
+ /* Avoid 32-bit overflow (dump bit buffer to top of output) */
+ if (bd->inbufBitCount >= 24) {
+ bits = bd->inbufBits&((1 << bd->inbufBitCount)-1);
+ bits_wanted -= bd->inbufBitCount;
+ bits <<= bits_wanted;
+ bd->inbufBitCount = 0;
+ }
+ /* Grab next 8 bits of input from buffer. */
+ bd->inbufBits = (bd->inbufBits << 8)|bd->inbuf[bd->inbufPos++];
+ bd->inbufBitCount += 8;
+ }
+ /* Calculate result */
+ bd->inbufBitCount -= bits_wanted;
+ bits |= (bd->inbufBits >> bd->inbufBitCount)&((1 << bits_wanted)-1);
+
+ return bits;
+}
+
+/* Unpacks the next block and sets up for the inverse burrows-wheeler step. */
+
+static int INIT get_next_block(struct bunzip_data *bd)
+{
+ struct group_data *hufGroup = NULL;
+ int *base = NULL;
+ int *limit = NULL;
+ int dbufCount, nextSym, dbufSize, groupCount, selector,
+ i, j, k, t, runPos, symCount, symTotal, nSelectors,
+ byteCount[256];
+ unsigned char uc, symToByte[256], mtfSymbol[256], *selectors;
+ unsigned int *dbuf, origPtr;
+
+ dbuf = bd->dbuf;
+ dbufSize = bd->dbufSize;
+ selectors = bd->selectors;
+
+ /* Read in header signature and CRC, then validate signature.
+ (last block signature means CRC is for whole file, return now) */
+ i = get_bits(bd, 24);
+ j = get_bits(bd, 24);
+ bd->headerCRC = get_bits(bd, 32);
+ if ((i == 0x177245) && (j == 0x385090))
+ return RETVAL_LAST_BLOCK;
+ if ((i != 0x314159) || (j != 0x265359))
+ return RETVAL_NOT_BZIP_DATA;
+ /* We can add support for blockRandomised if anybody complains.
+ There was some code for this in busybox 1.0.0-pre3, but nobody ever
+ noticed that it didn't actually work. */
+ if (get_bits(bd, 1))
+ return RETVAL_OBSOLETE_INPUT;
+ origPtr = get_bits(bd, 24);
+ if (origPtr > dbufSize)
+ return RETVAL_DATA_ERROR;
+ /* mapping table: if some byte values are never used (encoding things
+ like ascii text), the compression code removes the gaps to have fewer
+ symbols to deal with, and writes a sparse bitfield indicating which
+ values were present. We make a translation table to convert the
+ symbols back to the corresponding bytes. */
+ t = get_bits(bd, 16);
+ symTotal = 0;
+ for (i = 0; i < 16; i++) {
+ if (t&(1 << (15-i))) {
+ k = get_bits(bd, 16);
+ for (j = 0; j < 16; j++)
+ if (k&(1 << (15-j)))
+ symToByte[symTotal++] = (16*i)+j;
+ }
+ }
+ /* How many different Huffman coding groups does this block use? */
+ groupCount = get_bits(bd, 3);
+ if (groupCount < 2 || groupCount > MAX_GROUPS)
+ return RETVAL_DATA_ERROR;
+ /* nSelectors: Every GROUP_SIZE many symbols we select a new
+ Huffman coding group. Read in the group selector list,
+ which is stored as MTF encoded bit runs. (MTF = Move To
+ Front, as each value is used it's moved to the start of the
+ list.) */
+ nSelectors = get_bits(bd, 15);
+ if (!nSelectors)
+ return RETVAL_DATA_ERROR;
+ for (i = 0; i < groupCount; i++)
+ mtfSymbol[i] = i;
+ for (i = 0; i < nSelectors; i++) {
+ /* Get next value */
+ for (j = 0; get_bits(bd, 1); j++)
+ if (j >= groupCount)
+ return RETVAL_DATA_ERROR;
+ /* Decode MTF to get the next selector */
+ uc = mtfSymbol[j];
+ for (; j; j--)
+ mtfSymbol[j] = mtfSymbol[j-1];
+ mtfSymbol[0] = selectors[i] = uc;
+ }
+ /* Read the Huffman coding tables for each group, which code
+ for symTotal literal symbols, plus two run symbols (RUNA,
+ RUNB) */
+ symCount = symTotal+2;
+ for (j = 0; j < groupCount; j++) {
+ unsigned char length[MAX_SYMBOLS], temp[MAX_HUFCODE_BITS+1];
+ int minLen, maxLen, pp;
+ /* Read Huffman code lengths for each symbol. They're
+ stored in a way similar to mtf; record a starting
+ value for the first symbol, and an offset from the
+ previous value for everys symbol after that.
+ (Subtracting 1 before the loop and then adding it
+ back at the end is an optimization that makes the
+ test inside the loop simpler: symbol length 0
+ becomes negative, so an unsigned inequality catches
+ it.) */
+ t = get_bits(bd, 5)-1;
+ for (i = 0; i < symCount; i++) {
+ for (;;) {
+ if (((unsigned)t) > (MAX_HUFCODE_BITS-1))
+ return RETVAL_DATA_ERROR;
+
+ /* If first bit is 0, stop. Else
+ second bit indicates whether to
+ increment or decrement the value.
+ Optimization: grab 2 bits and unget
+ the second if the first was 0. */
+
+ k = get_bits(bd, 2);
+ if (k < 2) {
+ bd->inbufBitCount++;
+ break;
+ }
+ /* Add one if second bit 1, else
+ * subtract 1. Avoids if/else */
+ t += (((k+1)&2)-1);
+ }
+ /* Correct for the initial -1, to get the
+ * final symbol length */
+ length[i] = t+1;
+ }
+ /* Find largest and smallest lengths in this group */
+ minLen = maxLen = length[0];
+
+ for (i = 1; i < symCount; i++) {
+ if (length[i] > maxLen)
+ maxLen = length[i];
+ else if (length[i] < minLen)
+ minLen = length[i];
+ }
+
+ /* Calculate permute[], base[], and limit[] tables from
+ * length[].
+ *
+ * permute[] is the lookup table for converting
+ * Huffman coded symbols into decoded symbols. base[]
+ * is the amount to subtract from the value of a
+ * Huffman symbol of a given length when using
+ * permute[].
+ *
+ * limit[] indicates the largest numerical value a
+ * symbol with a given number of bits can have. This
+ * is how the Huffman codes can vary in length: each
+ * code with a value > limit[length] needs another
+ * bit.
+ */
+ hufGroup = bd->groups+j;
+ hufGroup->minLen = minLen;
+ hufGroup->maxLen = maxLen;
+ /* Note that minLen can't be smaller than 1, so we
+ adjust the base and limit array pointers so we're
+ not always wasting the first entry. We do this
+ again when using them (during symbol decoding).*/
+ base = hufGroup->base-1;
+ limit = hufGroup->limit-1;
+ /* Calculate permute[]. Concurently, initialize
+ * temp[] and limit[]. */
+ pp = 0;
+ for (i = minLen; i <= maxLen; i++) {
+ temp[i] = limit[i] = 0;
+ for (t = 0; t < symCount; t++)
+ if (length[t] == i)
+ hufGroup->permute[pp++] = t;
+ }
+ /* Count symbols coded for at each bit length */
+ for (i = 0; i < symCount; i++)
+ temp[length[i]]++;
+ /* Calculate limit[] (the largest symbol-coding value
+ *at each bit length, which is (previous limit <<
+ *1)+symbols at this level), and base[] (number of
+ *symbols to ignore at each bit length, which is limit
+ *minus the cumulative count of symbols coded for
+ *already). */
+ pp = t = 0;
+ for (i = minLen; i < maxLen; i++) {
+ pp += temp[i];
+ /* We read the largest possible symbol size
+ and then unget bits after determining how
+ many we need, and those extra bits could be
+ set to anything. (They're noise from
+ future symbols.) At each level we're
+ really only interested in the first few
+ bits, so here we set all the trailing
+ to-be-ignored bits to 1 so they don't
+ affect the value > limit[length]
+ comparison. */
+ limit[i] = (pp << (maxLen - i)) - 1;
+ pp <<= 1;
+ base[i+1] = pp-(t += temp[i]);
+ }
+ limit[maxLen+1] = INT_MAX; /* Sentinal value for
+ * reading next sym. */
+ limit[maxLen] = pp+temp[maxLen]-1;
+ base[minLen] = 0;
+ }
+ /* We've finished reading and digesting the block header. Now
+ read this block's Huffman coded symbols from the file and
+ undo the Huffman coding and run length encoding, saving the
+ result into dbuf[dbufCount++] = uc */
+
+ /* Initialize symbol occurrence counters and symbol Move To
+ * Front table */
+ for (i = 0; i < 256; i++) {
+ byteCount[i] = 0;
+ mtfSymbol[i] = (unsigned char)i;
+ }
+ /* Loop through compressed symbols. */
+ runPos = dbufCount = symCount = selector = 0;
+ for (;;) {
+ /* Determine which Huffman coding group to use. */
+ if (!(symCount--)) {
+ symCount = GROUP_SIZE-1;
+ if (selector >= nSelectors)
+ return RETVAL_DATA_ERROR;
+ hufGroup = bd->groups+selectors[selector++];
+ base = hufGroup->base-1;
+ limit = hufGroup->limit-1;
+ }
+ /* Read next Huffman-coded symbol. */
+ /* Note: It is far cheaper to read maxLen bits and
+ back up than it is to read minLen bits and then an
+ additional bit at a time, testing as we go.
+ Because there is a trailing last block (with file
+ CRC), there is no danger of the overread causing an
+ unexpected EOF for a valid compressed file. As a
+ further optimization, we do the read inline
+ (falling back to a call to get_bits if the buffer
+ runs dry). The following (up to got_huff_bits:) is
+ equivalent to j = get_bits(bd, hufGroup->maxLen);
+ */
+ while (bd->inbufBitCount < hufGroup->maxLen) {
+ if (bd->inbufPos == bd->inbufCount) {
+ j = get_bits(bd, hufGroup->maxLen);
+ goto got_huff_bits;
+ }
+ bd->inbufBits =
+ (bd->inbufBits << 8)|bd->inbuf[bd->inbufPos++];
+ bd->inbufBitCount += 8;
+ };
+ bd->inbufBitCount -= hufGroup->maxLen;
+ j = (bd->inbufBits >> bd->inbufBitCount)&
+ ((1 << hufGroup->maxLen)-1);
+got_huff_bits:
+ /* Figure how how many bits are in next symbol and
+ * unget extras */
+ i = hufGroup->minLen;
+ while (j > limit[i])
+ ++i;
+ bd->inbufBitCount += (hufGroup->maxLen - i);
+ /* Huffman decode value to get nextSym (with bounds checking) */
+ if ((i > hufGroup->maxLen)
+ || (((unsigned)(j = (j>>(hufGroup->maxLen-i))-base[i]))
+ >= MAX_SYMBOLS))
+ return RETVAL_DATA_ERROR;
+ nextSym = hufGroup->permute[j];
+ /* We have now decoded the symbol, which indicates
+ either a new literal byte, or a repeated run of the
+ most recent literal byte. First, check if nextSym
+ indicates a repeated run, and if so loop collecting
+ how many times to repeat the last literal. */
+ if (((unsigned)nextSym) <= SYMBOL_RUNB) { /* RUNA or RUNB */
+ /* If this is the start of a new run, zero out
+ * counter */
+ if (!runPos) {
+ runPos = 1;
+ t = 0;
+ }
+ /* Neat trick that saves 1 symbol: instead of
+ or-ing 0 or 1 at each bit position, add 1
+ or 2 instead. For example, 1011 is 1 << 0
+ + 1 << 1 + 2 << 2. 1010 is 2 << 0 + 2 << 1
+ + 1 << 2. You can make any bit pattern
+ that way using 1 less symbol than the basic
+ or 0/1 method (except all bits 0, which
+ would use no symbols, but a run of length 0
+ doesn't mean anything in this context).
+ Thus space is saved. */
+ t += (runPos << nextSym);
+ /* +runPos if RUNA; +2*runPos if RUNB */
+
+ runPos <<= 1;
+ continue;
+ }
+ /* When we hit the first non-run symbol after a run,
+ we now know how many times to repeat the last
+ literal, so append that many copies to our buffer
+ of decoded symbols (dbuf) now. (The last literal
+ used is the one at the head of the mtfSymbol
+ array.) */
+ if (runPos) {
+ runPos = 0;
+ if (dbufCount+t >= dbufSize)
+ return RETVAL_DATA_ERROR;
+
+ uc = symToByte[mtfSymbol[0]];
+ byteCount[uc] += t;
+ while (t--)
+ dbuf[dbufCount++] = uc;
+ }
+ /* Is this the terminating symbol? */
+ if (nextSym > symTotal)
+ break;
+ /* At this point, nextSym indicates a new literal
+ character. Subtract one to get the position in the
+ MTF array at which this literal is currently to be
+ found. (Note that the result can't be -1 or 0,
+ because 0 and 1 are RUNA and RUNB. But another
+ instance of the first symbol in the mtf array,
+ position 0, would have been handled as part of a
+ run above. Therefore 1 unused mtf position minus 2
+ non-literal nextSym values equals -1.) */
+ if (dbufCount >= dbufSize)
+ return RETVAL_DATA_ERROR;
+ i = nextSym - 1;
+ uc = mtfSymbol[i];
+ /* Adjust the MTF array. Since we typically expect to
+ *move only a small number of symbols, and are bound
+ *by 256 in any case, using memmove here would
+ *typically be bigger and slower due to function call
+ *overhead and other assorted setup costs. */
+ do {
+ mtfSymbol[i] = mtfSymbol[i-1];
+ } while (--i);
+ mtfSymbol[0] = uc;
+ uc = symToByte[uc];
+ /* We have our literal byte. Save it into dbuf. */
+ byteCount[uc]++;
+ dbuf[dbufCount++] = (unsigned int)uc;
+ }
+ /* At this point, we've read all the Huffman-coded symbols
+ (and repeated runs) for this block from the input stream,
+ and decoded them into the intermediate buffer. There are
+ dbufCount many decoded bytes in dbuf[]. Now undo the
+ Burrows-Wheeler transform on dbuf. See
+ http://dogma.net/markn/articles/bwt/bwt.htm
+ */
+ /* Turn byteCount into cumulative occurrence counts of 0 to n-1. */
+ j = 0;
+ for (i = 0; i < 256; i++) {
+ k = j+byteCount[i];
+ byteCount[i] = j;
+ j = k;
+ }
+ /* Figure out what order dbuf would be in if we sorted it. */
+ for (i = 0; i < dbufCount; i++) {
+ uc = (unsigned char)(dbuf[i] & 0xff);
+ dbuf[byteCount[uc]] |= (i << 8);
+ byteCount[uc]++;
+ }
+ /* Decode first byte by hand to initialize "previous" byte.
+ Note that it doesn't get output, and if the first three
+ characters are identical it doesn't qualify as a run (hence
+ writeRunCountdown = 5). */
+ if (dbufCount) {
+ if (origPtr >= dbufCount)
+ return RETVAL_DATA_ERROR;
+ bd->writePos = dbuf[origPtr];
+ bd->writeCurrent = (unsigned char)(bd->writePos&0xff);
+ bd->writePos >>= 8;
+ bd->writeRunCountdown = 5;
+ }
+ bd->writeCount = dbufCount;
+
+ return RETVAL_OK;
+}
+
+/* Undo burrows-wheeler transform on intermediate buffer to produce output.
+ If start_bunzip was initialized with out_fd =-1, then up to len bytes of
+ data are written to outbuf. Return value is number of bytes written or
+ error (all errors are negative numbers). If out_fd!=-1, outbuf and len
+ are ignored, data is written to out_fd and return is RETVAL_OK or error.
+*/
+
+static int INIT read_bunzip(struct bunzip_data *bd, unsigned char *outbuf, int
len)
+{
+ const unsigned int *dbuf;
+ int pos, xcurrent, previous, gotcount;
+
+ /* If last read was short due to end of file, return last block now */
+ if (bd->writeCount < 0)
+ return bd->writeCount;
+
+ gotcount = 0;
+ dbuf = bd->dbuf;
+ pos = bd->writePos;
+ xcurrent = bd->writeCurrent;
+
+ /* We will always have pending decoded data to write into the output
+ buffer unless this is the very first call (in which case we haven't
+ Huffman-decoded a block into the intermediate buffer yet). */
+
+ if (bd->writeCopies) {
+ /* Inside the loop, writeCopies means extra copies (beyond 1) */
+ --bd->writeCopies;
+ /* Loop outputting bytes */
+ for (;;) {
+ /* If the output buffer is full, snapshot
+ * state and return */
+ if (gotcount >= len) {
+ bd->writePos = pos;
+ bd->writeCurrent = xcurrent;
+ bd->writeCopies++;
+ return len;
+ }
+ /* Write next byte into output buffer, updating CRC */
+ outbuf[gotcount++] = xcurrent;
+ bd->writeCRC = (((bd->writeCRC) << 8)
+ ^bd->crc32Table[((bd->writeCRC) >> 24)
+ ^xcurrent]);
+ /* Loop now if we're outputting multiple
+ * copies of this byte */
+ if (bd->writeCopies) {
+ --bd->writeCopies;
+ continue;
+ }
+decode_next_byte:
+ if (!bd->writeCount--)
+ break;
+ /* Follow sequence vector to undo
+ * Burrows-Wheeler transform */
+ previous = xcurrent;
+ pos = dbuf[pos];
+ xcurrent = pos&0xff;
+ pos >>= 8;
+ /* After 3 consecutive copies of the same
+ byte, the 4th is a repeat count. We count
+ down from 4 instead *of counting up because
+ testing for non-zero is faster */
+ if (--bd->writeRunCountdown) {
+ if (xcurrent != previous)
+ bd->writeRunCountdown = 4;
+ } else {
+ /* We have a repeated run, this byte
+ * indicates the count */
+ bd->writeCopies = xcurrent;
+ xcurrent = previous;
+ bd->writeRunCountdown = 5;
+ /* Sometimes there are just 3 bytes
+ * (run length 0) */
+ if (!bd->writeCopies)
+ goto decode_next_byte;
+ /* Subtract the 1 copy we'd output
+ * anyway to get extras */
+ --bd->writeCopies;
+ }
+ }
+ /* Decompression of this block completed successfully */
+ bd->writeCRC = ~bd->writeCRC;
+ bd->totalCRC = ((bd->totalCRC << 1) |
+ (bd->totalCRC >> 31)) ^ bd->writeCRC;
+ /* If this block had a CRC error, force file level CRC error. */
+ if (bd->writeCRC != bd->headerCRC) {
+ bd->totalCRC = bd->headerCRC+1;
+ return RETVAL_LAST_BLOCK;
+ }
+ }
+
+ /* Refill the intermediate buffer by Huffman-decoding next
+ * block of input */
+ /* (previous is just a convenient unused temp variable here) */
+ previous = get_next_block(bd);
+ if (previous) {
+ bd->writeCount = previous;
+ return (previous != RETVAL_LAST_BLOCK) ? previous : gotcount;
+ }
+ bd->writeCRC = 0xffffffffUL;
+ pos = bd->writePos;
+ xcurrent = bd->writeCurrent;
+ goto decode_next_byte;
+}
+
+static int INIT nofill(void *buf, unsigned int len)
+{
+ return -1;
+}
+
+/* Allocate the structure, read file header. If in_fd ==-1, inbuf must contain
+ a complete bunzip file (len bytes long). If in_fd!=-1, inbuf and len are
+ ignored, and data is read from file handle into temporary buffer. */
+static int INIT start_bunzip(struct bunzip_data **bdp, void *inbuf, int len,
+ int (*fill)(void*, unsigned int))
+{
+ struct bunzip_data *bd;
+ unsigned int i, j, c;
+ const unsigned int BZh0 =
+ (((unsigned int)'B') << 24)+(((unsigned int)'Z') << 16)
+ +(((unsigned int)'h') << 8)+(unsigned int)'0';
+
+ /* Figure out how much data to allocate */
+ i = sizeof(struct bunzip_data);
+
+ /* Allocate bunzip_data. Most fields initialize to zero. */
+ bd = *bdp = malloc(i);
+ memset(bd, 0, sizeof(struct bunzip_data));
+ /* Setup input buffer */
+ bd->inbuf = inbuf;
+ bd->inbufCount = len;
+ if (fill != NULL)
+ bd->fill = fill;
+ else
+ bd->fill = nofill;
+
+ /* Init the CRC32 table (big endian) */
+ for (i = 0; i < 256; i++) {
+ c = i << 24;
+ for (j = 8; j; j--)
+ c = c&0x80000000 ? (c << 1)^0x04c11db7 : (c << 1);
+ bd->crc32Table[i] = c;
+ }
+
+ /* Ensure that file starts with "BZh['1'-'9']." */
+ i = get_bits(bd, 32);
+ if (((unsigned int)(i-BZh0-1)) >= 9)
+ return RETVAL_NOT_BZIP_DATA;
+
+ /* Fourth byte (ascii '1'-'9'), indicates block size in units of 100k of
+ uncompressed data. Allocate intermediate buffer for block. */
+ bd->dbufSize = 100000*(i-BZh0);
+
+ bd->dbuf = large_malloc(bd->dbufSize * sizeof(int));
+ return RETVAL_OK;
+}
+
+/* Example usage: decompress src_fd to dst_fd. (Stops at end of bzip2 data,
+ not end of file.) */
+STATIC int INIT bunzip2(unsigned char *buf, unsigned int len,
+ int(*fill)(void*, unsigned int),
+ int(*flush)(void*, unsigned int),
+ unsigned char *outbuf,
+ unsigned int *pos,
+ void(*error_fn)(const char *x))
+{
+ struct bunzip_data *bd;
+ int i = -1;
+ unsigned char *inbuf;
+
+ set_error_fn(error_fn);
+ if (flush)
+ outbuf = malloc(BZIP2_IOBUF_SIZE);
+
+ if (!outbuf) {
+ error("Could not allocate output bufer");
+ return -1;
+ }
+ if (buf)
+ inbuf = buf;
+ else
+ inbuf = malloc(BZIP2_IOBUF_SIZE);
+ if (!inbuf) {
+ error("Could not allocate input bufer");
+ goto exit_0;
+ }
+ i = start_bunzip(&bd, inbuf, len, fill);
+ if (!i) {
+ for (;;) {
+ i = read_bunzip(bd, outbuf, BZIP2_IOBUF_SIZE);
+ if (i <= 0)
+ break;
+ if (!flush)
+ outbuf += i;
+ else
+ if (i != flush(outbuf, i)) {
+ i = RETVAL_UNEXPECTED_OUTPUT_EOF;
+ break;
+ }
+ }
+ }
+ /* Check CRC and release memory */
+ if (i == RETVAL_LAST_BLOCK) {
+ if (bd->headerCRC != bd->totalCRC)
+ error("Data integrity error when decompressing.");
+ else
+ i = RETVAL_OK;
+ } else if (i == RETVAL_UNEXPECTED_OUTPUT_EOF) {
+ error("Compressed file ends unexpectedly");
+ }
+ if (bd->dbuf)
+ large_free(bd->dbuf);
+ if (pos)
+ *pos = bd->inbufPos;
+ free(bd);
+ if (!buf)
+ free(inbuf);
+exit_0:
+ if (flush)
+ free(outbuf);
+ return i;
+}
--- /dev/null 1970-01-01 00:00:00.000000000 +0000
+++ 2009-10-27/xen/common/decompress.c 2009-11-05 12:27:10.000000000 +0100
@@ -0,0 +1,27 @@
+#include <xen/config.h>
+#include <xen/init.h>
+#include <xen/lib.h>
+#include <xen/string.h>
+#include <xen/decompress.h>
+
+static void __init error(const char *msg)
+{
+ printk("%s\n", msg);
+}
+
+int __init decompress(void *inbuf, unsigned int len, void *outbuf)
+{
+#if 0 /* Not needed here yet. */
+ if ( len >= 2 &&
+ (!memcmp(inbuf, "\037\213", 2) || !memcmp(inbuf, "\037\236", 2)) )
+ return gunzip(inbuf, len, NULL, NULL, outbuf, NULL, error);
+#endif
+
+ if ( len >= 3 && !memcmp(inbuf, "\x42\x5a\x68", 3) )
+ return bunzip2(inbuf, len, NULL, NULL, outbuf, NULL, error);
+
+ if ( len >= 2 && !memcmp(inbuf, "\135\000", 2) )
+ return unlzma(inbuf, len, NULL, NULL, outbuf, NULL, error);
+
+ return 1;
+}
--- /dev/null 1970-01-01 00:00:00.000000000 +0000
+++ 2009-10-27/xen/common/decompress.h 2009-11-05 15:21:52.000000000 +0100
@@ -0,0 +1,19 @@
+#include <xen/config.h>
+#include <xen/cache.h>
+#include <xen/decompress.h>
+#include <xen/init.h>
+#include <xen/string.h>
+#include <xen/types.h>
+#include <xen/xmalloc.h>
+
+#define STATIC
+#define INIT __init
+
+static void(*__initdata error)(const char *);
+#define set_error_fn(x) error = x;
+
+#define malloc xmalloc_bytes
+#define free xfree
+
+#define large_malloc xmalloc_bytes
+#define large_free xfree
--- /dev/null 1970-01-01 00:00:00.000000000 +0000
+++ 2009-10-27/xen/common/unlzma.c 2009-11-05 12:45:37.000000000 +0100
@@ -0,0 +1,647 @@
+/* Lzma decompressor for Linux kernel. Shamelessly snarfed
+ * from busybox 1.1.1
+ *
+ * Linux kernel adaptation
+ * Copyright (C) 2006 Alain < alain@xxxxxxxx >
+ *
+ * Based on small lzma deflate implementation/Small range coder
+ * implementation for lzma.
+ * Copyright (C) 2006 Aurelien Jacobs < aurel@xxxxxxxxxx >
+ *
+ * Based on LzmaDecode.c from the LZMA SDK 4.22 (http://www.7-zip.org/)
+ * Copyright (C) 1999-2005 Igor Pavlov
+ *
+ * Copyrights of the parts, see headers below.
+ *
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include "decompress.h"
+
+#define MIN(a, b) (((a) < (b)) ? (a) : (b))
+
+static long long INIT read_int(unsigned char *ptr, int size)
+{
+ int i;
+ long long ret = 0;
+
+ for (i = 0; i < size; i++)
+ ret = (ret << 8) | ptr[size-i-1];
+ return ret;
+}
+
+#define ENDIAN_CONVERT(x) \
+ x = (typeof(x))read_int((unsigned char *)&x, sizeof(x))
+
+
+/* Small range coder implementation for lzma.
+ * Copyright (C) 2006 Aurelien Jacobs < aurel@xxxxxxxxxx >
+ *
+ * Based on LzmaDecode.c from the LZMA SDK 4.22 (http://www.7-zip.org/)
+ * Copyright (c) 1999-2005 Igor Pavlov
+ */
+
+#include <xen/compiler.h>
+
+#define LZMA_IOBUF_SIZE 0x10000
+
+struct rc {
+ int (*fill)(void*, unsigned int);
+ uint8_t *ptr;
+ uint8_t *buffer;
+ uint8_t *buffer_end;
+ int buffer_size;
+ uint32_t code;
+ uint32_t range;
+ uint32_t bound;
+};
+
+
+#define RC_TOP_BITS 24
+#define RC_MOVE_BITS 5
+#define RC_MODEL_TOTAL_BITS 11
+
+
+static int nofill(void *buffer, unsigned int len)
+{
+ return -1;
+}
+
+/* Called twice: once at startup and once in rc_normalize() */
+static void INIT rc_read(struct rc *rc)
+{
+ rc->buffer_size = rc->fill((char *)rc->buffer, LZMA_IOBUF_SIZE);
+ if (rc->buffer_size <= 0)
+ error("unexpected EOF");
+ rc->ptr = rc->buffer;
+ rc->buffer_end = rc->buffer + rc->buffer_size;
+}
+
+/* Called once */
+static inline void INIT rc_init(struct rc *rc,
+ int (*fill)(void*, unsigned int),
+ unsigned char *buffer, int buffer_size)
+{
+ if (fill)
+ rc->fill = fill;
+ else
+ rc->fill = nofill;
+ rc->buffer = (uint8_t *)buffer;
+ rc->buffer_size = buffer_size;
+ rc->buffer_end = rc->buffer + rc->buffer_size;
+ rc->ptr = rc->buffer;
+
+ rc->code = 0;
+ rc->range = 0xFFFFFFFF;
+}
+
+static inline void INIT rc_init_code(struct rc *rc)
+{
+ int i;
+
+ for (i = 0; i < 5; i++) {
+ if (rc->ptr >= rc->buffer_end)
+ rc_read(rc);
+ rc->code = (rc->code << 8) | *rc->ptr++;
+ }
+}
+
+
+/* Called once. TODO: bb_maybe_free() */
+static inline void INIT rc_free(struct rc *rc)
+{
+ free(rc->buffer);
+}
+
+/* Called twice, but one callsite is in inline'd rc_is_bit_0_helper() */
+static void INIT rc_do_normalize(struct rc *rc)
+{
+ if (rc->ptr >= rc->buffer_end)
+ rc_read(rc);
+ rc->range <<= 8;
+ rc->code = (rc->code << 8) | *rc->ptr++;
+}
+static inline void INIT rc_normalize(struct rc *rc)
+{
+ if (rc->range < (1 << RC_TOP_BITS))
+ rc_do_normalize(rc);
+}
+
+/* Called 9 times */
+/* Why rc_is_bit_0_helper exists?
+ *Because we want to always expose (rc->code < rc->bound) to optimizer
+ */
+static inline uint32_t INIT rc_is_bit_0_helper(struct rc *rc, uint16_t *p)
+{
+ rc_normalize(rc);
+ rc->bound = *p * (rc->range >> RC_MODEL_TOTAL_BITS);
+ return rc->bound;
+}
+static inline int INIT rc_is_bit_0(struct rc *rc, uint16_t *p)
+{
+ uint32_t t = rc_is_bit_0_helper(rc, p);
+ return rc->code < t;
+}
+
+/* Called ~10 times, but very small, thus inlined */
+static inline void INIT rc_update_bit_0(struct rc *rc, uint16_t *p)
+{
+ rc->range = rc->bound;
+ *p += ((1 << RC_MODEL_TOTAL_BITS) - *p) >> RC_MOVE_BITS;
+}
+static inline void rc_update_bit_1(struct rc *rc, uint16_t *p)
+{
+ rc->range -= rc->bound;
+ rc->code -= rc->bound;
+ *p -= *p >> RC_MOVE_BITS;
+}
+
+/* Called 4 times in unlzma loop */
+static int INIT rc_get_bit(struct rc *rc, uint16_t *p, int *symbol)
+{
+ if (rc_is_bit_0(rc, p)) {
+ rc_update_bit_0(rc, p);
+ *symbol *= 2;
+ return 0;
+ } else {
+ rc_update_bit_1(rc, p);
+ *symbol = *symbol * 2 + 1;
+ return 1;
+ }
+}
+
+/* Called once */
+static inline int INIT rc_direct_bit(struct rc *rc)
+{
+ rc_normalize(rc);
+ rc->range >>= 1;
+ if (rc->code >= rc->range) {
+ rc->code -= rc->range;
+ return 1;
+ }
+ return 0;
+}
+
+/* Called twice */
+static inline void INIT
+rc_bit_tree_decode(struct rc *rc, uint16_t *p, int num_levels, int *symbol)
+{
+ int i = num_levels;
+
+ *symbol = 1;
+ while (i--)
+ rc_get_bit(rc, p + *symbol, symbol);
+ *symbol -= 1 << num_levels;
+}
+
+
+/*
+ * Small lzma deflate implementation.
+ * Copyright (C) 2006 Aurelien Jacobs < aurel@xxxxxxxxxx >
+ *
+ * Based on LzmaDecode.c from the LZMA SDK 4.22 (http://www.7-zip.org/)
+ * Copyright (C) 1999-2005 Igor Pavlov
+ */
+
+
+struct lzma_header {
+ uint8_t pos;
+ uint32_t dict_size;
+ uint64_t dst_size;
+} __attribute__ ((packed)) ;
+
+
+#define LZMA_BASE_SIZE 1846
+#define LZMA_LIT_SIZE 768
+
+#define LZMA_NUM_POS_BITS_MAX 4
+
+#define LZMA_LEN_NUM_LOW_BITS 3
+#define LZMA_LEN_NUM_MID_BITS 3
+#define LZMA_LEN_NUM_HIGH_BITS 8
+
+#define LZMA_LEN_CHOICE 0
+#define LZMA_LEN_CHOICE_2 (LZMA_LEN_CHOICE + 1)
+#define LZMA_LEN_LOW (LZMA_LEN_CHOICE_2 + 1)
+#define LZMA_LEN_MID (LZMA_LEN_LOW \
+ + (1 << (LZMA_NUM_POS_BITS_MAX + LZMA_LEN_NUM_LOW_BITS)))
+#define LZMA_LEN_HIGH (LZMA_LEN_MID \
+ +(1 << (LZMA_NUM_POS_BITS_MAX + LZMA_LEN_NUM_MID_BITS)))
+#define LZMA_NUM_LEN_PROBS (LZMA_LEN_HIGH + (1 << LZMA_LEN_NUM_HIGH_BITS))
+
+#define LZMA_NUM_STATES 12
+#define LZMA_NUM_LIT_STATES 7
+
+#define LZMA_START_POS_MODEL_INDEX 4
+#define LZMA_END_POS_MODEL_INDEX 14
+#define LZMA_NUM_FULL_DISTANCES (1 << (LZMA_END_POS_MODEL_INDEX >> 1))
+
+#define LZMA_NUM_POS_SLOT_BITS 6
+#define LZMA_NUM_LEN_TO_POS_STATES 4
+
+#define LZMA_NUM_ALIGN_BITS 4
+
+#define LZMA_MATCH_MIN_LEN 2
+
+#define LZMA_IS_MATCH 0
+#define LZMA_IS_REP (LZMA_IS_MATCH + (LZMA_NUM_STATES <<
LZMA_NUM_POS_BITS_MAX))
+#define LZMA_IS_REP_G0 (LZMA_IS_REP + LZMA_NUM_STATES)
+#define LZMA_IS_REP_G1 (LZMA_IS_REP_G0 + LZMA_NUM_STATES)
+#define LZMA_IS_REP_G2 (LZMA_IS_REP_G1 + LZMA_NUM_STATES)
+#define LZMA_IS_REP_0_LONG (LZMA_IS_REP_G2 + LZMA_NUM_STATES)
+#define LZMA_POS_SLOT (LZMA_IS_REP_0_LONG \
+ + (LZMA_NUM_STATES << LZMA_NUM_POS_BITS_MAX))
+#define LZMA_SPEC_POS (LZMA_POS_SLOT \
+ +(LZMA_NUM_LEN_TO_POS_STATES << LZMA_NUM_POS_SLOT_BITS))
+#define LZMA_ALIGN (LZMA_SPEC_POS \
+ + LZMA_NUM_FULL_DISTANCES - LZMA_END_POS_MODEL_INDEX)
+#define LZMA_LEN_CODER (LZMA_ALIGN + (1 << LZMA_NUM_ALIGN_BITS))
+#define LZMA_REP_LEN_CODER (LZMA_LEN_CODER + LZMA_NUM_LEN_PROBS)
+#define LZMA_LITERAL (LZMA_REP_LEN_CODER + LZMA_NUM_LEN_PROBS)
+
+
+struct writer {
+ uint8_t *buffer;
+ uint8_t previous_byte;
+ size_t buffer_pos;
+ int bufsize;
+ size_t global_pos;
+ int(*flush)(void*, unsigned int);
+ struct lzma_header *header;
+};
+
+struct cstate {
+ int state;
+ uint32_t rep0, rep1, rep2, rep3;
+};
+
+static inline size_t INIT get_pos(struct writer *wr)
+{
+ return
+ wr->global_pos + wr->buffer_pos;
+}
+
+static inline uint8_t INIT peek_old_byte(struct writer *wr,
+ uint32_t offs)
+{
+ if (!wr->flush) {
+ int32_t pos;
+ while (offs > wr->header->dict_size)
+ offs -= wr->header->dict_size;
+ pos = wr->buffer_pos - offs;
+ return wr->buffer[pos];
+ } else {
+ uint32_t pos = wr->buffer_pos - offs;
+ while (pos >= wr->header->dict_size)
+ pos += wr->header->dict_size;
+ return wr->buffer[pos];
+ }
+
+}
+
+static inline void INIT write_byte(struct writer *wr, uint8_t byte)
+{
+ wr->buffer[wr->buffer_pos++] = wr->previous_byte = byte;
+ if (wr->flush && wr->buffer_pos == wr->header->dict_size) {
+ wr->buffer_pos = 0;
+ wr->global_pos += wr->header->dict_size;
+ wr->flush((char *)wr->buffer, wr->header->dict_size);
+ }
+}
+
+
+static inline void INIT copy_byte(struct writer *wr, uint32_t offs)
+{
+ write_byte(wr, peek_old_byte(wr, offs));
+}
+
+static inline void INIT copy_bytes(struct writer *wr,
+ uint32_t rep0, int len)
+{
+ do {
+ copy_byte(wr, rep0);
+ len--;
+ } while (len != 0 && wr->buffer_pos < wr->header->dst_size);
+}
+
+static inline void INIT process_bit0(struct writer *wr, struct rc *rc,
+ struct cstate *cst, uint16_t *p,
+ int pos_state, uint16_t *prob,
+ int lc, uint32_t literal_pos_mask) {
+ int mi = 1;
+ rc_update_bit_0(rc, prob);
+ prob = (p + LZMA_LITERAL +
+ (LZMA_LIT_SIZE
+ * (((get_pos(wr) & literal_pos_mask) << lc)
+ + (wr->previous_byte >> (8 - lc))))
+ );
+
+ if (cst->state >= LZMA_NUM_LIT_STATES) {
+ int match_byte = peek_old_byte(wr, cst->rep0);
+ do {
+ int bit;
+ uint16_t *prob_lit;
+
+ match_byte <<= 1;
+ bit = match_byte & 0x100;
+ prob_lit = prob + 0x100 + bit + mi;
+ if (rc_get_bit(rc, prob_lit, &mi)) {
+ if (!bit)
+ break;
+ } else {
+ if (bit)
+ break;
+ }
+ } while (mi < 0x100);
+ }
+ while (mi < 0x100) {
+ uint16_t *prob_lit = prob + mi;
+ rc_get_bit(rc, prob_lit, &mi);
+ }
+ write_byte(wr, mi);
+ if (cst->state < 4)
+ cst->state = 0;
+ else if (cst->state < 10)
+ cst->state -= 3;
+ else
+ cst->state -= 6;
+}
+
+static inline void INIT process_bit1(struct writer *wr, struct rc *rc,
+ struct cstate *cst, uint16_t *p,
+ int pos_state, uint16_t *prob) {
+ int offset;
+ uint16_t *prob_len;
+ int num_bits;
+ int len;
+
+ rc_update_bit_1(rc, prob);
+ prob = p + LZMA_IS_REP + cst->state;
+ if (rc_is_bit_0(rc, prob)) {
+ rc_update_bit_0(rc, prob);
+ cst->rep3 = cst->rep2;
+ cst->rep2 = cst->rep1;
+ cst->rep1 = cst->rep0;
+ cst->state = cst->state < LZMA_NUM_LIT_STATES ? 0 : 3;
+ prob = p + LZMA_LEN_CODER;
+ } else {
+ rc_update_bit_1(rc, prob);
+ prob = p + LZMA_IS_REP_G0 + cst->state;
+ if (rc_is_bit_0(rc, prob)) {
+ rc_update_bit_0(rc, prob);
+ prob = (p + LZMA_IS_REP_0_LONG
+ + (cst->state <<
+ LZMA_NUM_POS_BITS_MAX) +
+ pos_state);
+ if (rc_is_bit_0(rc, prob)) {
+ rc_update_bit_0(rc, prob);
+
+ cst->state = cst->state < LZMA_NUM_LIT_STATES ?
+ 9 : 11;
+ copy_byte(wr, cst->rep0);
+ return;
+ } else {
+ rc_update_bit_1(rc, prob);
+ }
+ } else {
+ uint32_t distance;
+
+ rc_update_bit_1(rc, prob);
+ prob = p + LZMA_IS_REP_G1 + cst->state;
+ if (rc_is_bit_0(rc, prob)) {
+ rc_update_bit_0(rc, prob);
+ distance = cst->rep1;
+ } else {
+ rc_update_bit_1(rc, prob);
+ prob = p + LZMA_IS_REP_G2 + cst->state;
+ if (rc_is_bit_0(rc, prob)) {
+ rc_update_bit_0(rc, prob);
+ distance = cst->rep2;
+ } else {
+ rc_update_bit_1(rc, prob);
+ distance = cst->rep3;
+ cst->rep3 = cst->rep2;
+ }
+ cst->rep2 = cst->rep1;
+ }
+ cst->rep1 = cst->rep0;
+ cst->rep0 = distance;
+ }
+ cst->state = cst->state < LZMA_NUM_LIT_STATES ? 8 : 11;
+ prob = p + LZMA_REP_LEN_CODER;
+ }
+
+ prob_len = prob + LZMA_LEN_CHOICE;
+ if (rc_is_bit_0(rc, prob_len)) {
+ rc_update_bit_0(rc, prob_len);
+ prob_len = (prob + LZMA_LEN_LOW
+ + (pos_state <<
+ LZMA_LEN_NUM_LOW_BITS));
+ offset = 0;
+ num_bits = LZMA_LEN_NUM_LOW_BITS;
+ } else {
+ rc_update_bit_1(rc, prob_len);
+ prob_len = prob + LZMA_LEN_CHOICE_2;
+ if (rc_is_bit_0(rc, prob_len)) {
+ rc_update_bit_0(rc, prob_len);
+ prob_len = (prob + LZMA_LEN_MID
+ + (pos_state <<
+ LZMA_LEN_NUM_MID_BITS));
+ offset = 1 << LZMA_LEN_NUM_LOW_BITS;
+ num_bits = LZMA_LEN_NUM_MID_BITS;
+ } else {
+ rc_update_bit_1(rc, prob_len);
+ prob_len = prob + LZMA_LEN_HIGH;
+ offset = ((1 << LZMA_LEN_NUM_LOW_BITS)
+ + (1 << LZMA_LEN_NUM_MID_BITS));
+ num_bits = LZMA_LEN_NUM_HIGH_BITS;
+ }
+ }
+
+ rc_bit_tree_decode(rc, prob_len, num_bits, &len);
+ len += offset;
+
+ if (cst->state < 4) {
+ int pos_slot;
+
+ cst->state += LZMA_NUM_LIT_STATES;
+ prob =
+ p + LZMA_POS_SLOT +
+ ((len <
+ LZMA_NUM_LEN_TO_POS_STATES ? len :
+ LZMA_NUM_LEN_TO_POS_STATES - 1)
+ << LZMA_NUM_POS_SLOT_BITS);
+ rc_bit_tree_decode(rc, prob,
+ LZMA_NUM_POS_SLOT_BITS,
+ &pos_slot);
+ if (pos_slot >= LZMA_START_POS_MODEL_INDEX) {
+ int i, mi;
+ num_bits = (pos_slot >> 1) - 1;
+ cst->rep0 = 2 | (pos_slot & 1);
+ if (pos_slot < LZMA_END_POS_MODEL_INDEX) {
+ cst->rep0 <<= num_bits;
+ prob = p + LZMA_SPEC_POS +
+ cst->rep0 - pos_slot - 1;
+ } else {
+ num_bits -= LZMA_NUM_ALIGN_BITS;
+ while (num_bits--)
+ cst->rep0 = (cst->rep0 << 1) |
+ rc_direct_bit(rc);
+ prob = p + LZMA_ALIGN;
+ cst->rep0 <<= LZMA_NUM_ALIGN_BITS;
+ num_bits = LZMA_NUM_ALIGN_BITS;
+ }
+ i = 1;
+ mi = 1;
+ while (num_bits--) {
+ if (rc_get_bit(rc, prob + mi, &mi))
+ cst->rep0 |= i;
+ i <<= 1;
+ }
+ } else
+ cst->rep0 = pos_slot;
+ if (++(cst->rep0) == 0)
+ return;
+ }
+
+ len += LZMA_MATCH_MIN_LEN;
+
+ copy_bytes(wr, cst->rep0, len);
+}
+
+
+
+STATIC inline int INIT unlzma(unsigned char *buf, unsigned int in_len,
+ int(*fill)(void*, unsigned int),
+ int(*flush)(void*, unsigned int),
+ unsigned char *output,
+ unsigned int *posp,
+ void(*error_fn)(const char *x)
+ )
+{
+ struct lzma_header header;
+ int lc, pb, lp;
+ uint32_t pos_state_mask;
+ uint32_t literal_pos_mask;
+ uint16_t *p;
+ int num_probs;
+ struct rc rc;
+ int i, mi;
+ struct writer wr;
+ struct cstate cst;
+ unsigned char *inbuf;
+ int ret = -1;
+
+ set_error_fn(error_fn);
+
+ if (buf)
+ inbuf = buf;
+ else
+ inbuf = malloc(LZMA_IOBUF_SIZE);
+ if (!inbuf) {
+ error("Could not allocate input bufer");
+ goto exit_0;
+ }
+
+ cst.state = 0;
+ cst.rep0 = cst.rep1 = cst.rep2 = cst.rep3 = 1;
+
+ wr.header = &header;
+ wr.flush = flush;
+ wr.global_pos = 0;
+ wr.previous_byte = 0;
+ wr.buffer_pos = 0;
+
+ rc_init(&rc, fill, inbuf, in_len);
+
+ for (i = 0; i < sizeof(header); i++) {
+ if (rc.ptr >= rc.buffer_end)
+ rc_read(&rc);
+ ((unsigned char *)&header)[i] = *rc.ptr++;
+ }
+
+ if (header.pos >= (9 * 5 * 5))
+ error("bad header");
+
+ mi = 0;
+ lc = header.pos;
+ while (lc >= 9) {
+ mi++;
+ lc -= 9;
+ }
+ pb = 0;
+ lp = mi;
+ while (lp >= 5) {
+ pb++;
+ lp -= 5;
+ }
+ pos_state_mask = (1 << pb) - 1;
+ literal_pos_mask = (1 << lp) - 1;
+
+ ENDIAN_CONVERT(header.dict_size);
+ ENDIAN_CONVERT(header.dst_size);
+
+ if (header.dict_size == 0)
+ header.dict_size = 1;
+
+ if (output)
+ wr.buffer = output;
+ else {
+ wr.bufsize = MIN(header.dst_size, header.dict_size);
+ wr.buffer = large_malloc(wr.bufsize);
+ }
+ if (wr.buffer == NULL)
+ goto exit_1;
+
+ num_probs = LZMA_BASE_SIZE + (LZMA_LIT_SIZE << (lc + lp));
+ p = (uint16_t *) large_malloc(num_probs * sizeof(*p));
+ if (p == 0)
+ goto exit_2;
+ num_probs = LZMA_LITERAL + (LZMA_LIT_SIZE << (lc + lp));
+ for (i = 0; i < num_probs; i++)
+ p[i] = (1 << RC_MODEL_TOTAL_BITS) >> 1;
+
+ rc_init_code(&rc);
+
+ while (get_pos(&wr) < header.dst_size) {
+ int pos_state = get_pos(&wr) & pos_state_mask;
+ uint16_t *prob = p + LZMA_IS_MATCH +
+ (cst.state << LZMA_NUM_POS_BITS_MAX) + pos_state;
+ if (rc_is_bit_0(&rc, prob))
+ process_bit0(&wr, &rc, &cst, p, pos_state, prob,
+ lc, literal_pos_mask);
+ else {
+ process_bit1(&wr, &rc, &cst, p, pos_state, prob);
+ if (cst.rep0 == 0)
+ break;
+ }
+ }
+
+ if (posp)
+ *posp = rc.ptr-rc.buffer;
+ if (wr.flush)
+ wr.flush(wr.buffer, wr.buffer_pos);
+ ret = 0;
+ large_free(p);
+exit_2:
+ if (!output)
+ large_free(wr.buffer);
+exit_1:
+ if (!buf)
+ free(inbuf);
+exit_0:
+ return ret;
+}
--- /dev/null 1970-01-01 00:00:00.000000000 +0000
+++ 2009-10-27/xen/include/xen/decompress.h 2009-11-05 12:27:44.000000000
+0100
@@ -0,0 +1,38 @@
+#ifndef __XEN_GENERIC_H
+#define __XEN_GENERIC_H
+
+typedef int decompress_fn(unsigned char *inbuf, unsigned int len,
+ int (*fill)(void*, unsigned int),
+ int (*flush)(void*, unsigned int),
+ unsigned char *outbuf, unsigned int *posp,
+ void (*error)(const char *x));
+
+/* inbuf - input buffer
+ * len - len of pre-read data in inbuf
+ * fill - function to fill inbuf when empty
+ * flush - function to write out outbuf
+ * outbuf - output buffer
+ * posp - if non-null, input position (number of bytes read) will be
+ * returned here
+ * error - error reporting function
+ *
+ * If len != 0, inbuf should contain all the necessary input data, and fill
+ * should be NULL
+ * If len = 0, inbuf can be NULL, in which case the decompressor will allocate
+ * the input buffer. If inbuf != NULL it must be at least XXX_IOBUF_SIZE
bytes.
+ * fill will be called (repeatedly...) to read data, at most XXX_IOBUF_SIZE
+ * bytes should be read per call. Replace XXX with the appropriate
decompressor
+ * name, i.e. LZMA_IOBUF_SIZE.
+ *
+ * If flush = NULL, outbuf must be large enough to buffer all the expected
+ * output. If flush != NULL, the output buffer will be allocated by the
+ * decompressor (outbuf = NULL), and the flush function will be called to
+ * flush the output buffer at the appropriate time (decompressor and stream
+ * dependent).
+ */
+
+decompress_fn bunzip2, unlzma;
+
+int decompress(void *inbuf, unsigned int len, void *outbuf);
+
+#endif
Attachment:
xen-x86-advanced-decompress.patch _______________________________________________ Xen-devel mailing list Xen-devel@xxxxxxxxxxxxxxxxxxx http://lists.xensource.com/xen-devel
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