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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
commitace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch)
treeb2d64bc10158fdd5497876388cd68142ca374ed3 /lib/lz4/lz4_decompress.c
parentInitial commit. (diff)
downloadlinux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz
linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'lib/lz4/lz4_decompress.c')
-rw-r--r--lib/lz4/lz4_decompress.c720
1 files changed, 720 insertions, 0 deletions
diff --git a/lib/lz4/lz4_decompress.c b/lib/lz4/lz4_decompress.c
new file mode 100644
index 0000000000..59fe69a638
--- /dev/null
+++ b/lib/lz4/lz4_decompress.c
@@ -0,0 +1,720 @@
+/*
+ * LZ4 - Fast LZ compression algorithm
+ * Copyright (C) 2011 - 2016, Yann Collet.
+ * BSD 2 - Clause License (http://www.opensource.org/licenses/bsd - license.php)
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ * * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * You can contact the author at :
+ * - LZ4 homepage : http://www.lz4.org
+ * - LZ4 source repository : https://github.com/lz4/lz4
+ *
+ * Changed for kernel usage by:
+ * Sven Schmidt <4sschmid@informatik.uni-hamburg.de>
+ */
+
+/*-************************************
+ * Dependencies
+ **************************************/
+#include <linux/lz4.h>
+#include "lz4defs.h"
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <asm/unaligned.h>
+
+/*-*****************************
+ * Decompression functions
+ *******************************/
+
+#define DEBUGLOG(l, ...) {} /* disabled */
+
+#ifndef assert
+#define assert(condition) ((void)0)
+#endif
+
+/*
+ * LZ4_decompress_generic() :
+ * This generic decompression function covers all use cases.
+ * It shall be instantiated several times, using different sets of directives.
+ * Note that it is important for performance that this function really get inlined,
+ * in order to remove useless branches during compilation optimization.
+ */
+static FORCE_INLINE int LZ4_decompress_generic(
+ const char * const src,
+ char * const dst,
+ int srcSize,
+ /*
+ * If endOnInput == endOnInputSize,
+ * this value is `dstCapacity`
+ */
+ int outputSize,
+ /* endOnOutputSize, endOnInputSize */
+ endCondition_directive endOnInput,
+ /* full, partial */
+ earlyEnd_directive partialDecoding,
+ /* noDict, withPrefix64k, usingExtDict */
+ dict_directive dict,
+ /* always <= dst, == dst when no prefix */
+ const BYTE * const lowPrefix,
+ /* only if dict == usingExtDict */
+ const BYTE * const dictStart,
+ /* note : = 0 if noDict */
+ const size_t dictSize
+ )
+{
+ const BYTE *ip = (const BYTE *) src;
+ const BYTE * const iend = ip + srcSize;
+
+ BYTE *op = (BYTE *) dst;
+ BYTE * const oend = op + outputSize;
+ BYTE *cpy;
+
+ const BYTE * const dictEnd = (const BYTE *)dictStart + dictSize;
+ static const unsigned int inc32table[8] = {0, 1, 2, 1, 0, 4, 4, 4};
+ static const int dec64table[8] = {0, 0, 0, -1, -4, 1, 2, 3};
+
+ const int safeDecode = (endOnInput == endOnInputSize);
+ const int checkOffset = ((safeDecode) && (dictSize < (int)(64 * KB)));
+
+ /* Set up the "end" pointers for the shortcut. */
+ const BYTE *const shortiend = iend -
+ (endOnInput ? 14 : 8) /*maxLL*/ - 2 /*offset*/;
+ const BYTE *const shortoend = oend -
+ (endOnInput ? 14 : 8) /*maxLL*/ - 18 /*maxML*/;
+
+ DEBUGLOG(5, "%s (srcSize:%i, dstSize:%i)", __func__,
+ srcSize, outputSize);
+
+ /* Special cases */
+ assert(lowPrefix <= op);
+ assert(src != NULL);
+
+ /* Empty output buffer */
+ if ((endOnInput) && (unlikely(outputSize == 0)))
+ return ((srcSize == 1) && (*ip == 0)) ? 0 : -1;
+
+ if ((!endOnInput) && (unlikely(outputSize == 0)))
+ return (*ip == 0 ? 1 : -1);
+
+ if ((endOnInput) && unlikely(srcSize == 0))
+ return -1;
+
+ /* Main Loop : decode sequences */
+ while (1) {
+ size_t length;
+ const BYTE *match;
+ size_t offset;
+
+ /* get literal length */
+ unsigned int const token = *ip++;
+ length = token>>ML_BITS;
+
+ /* ip < iend before the increment */
+ assert(!endOnInput || ip <= iend);
+
+ /*
+ * A two-stage shortcut for the most common case:
+ * 1) If the literal length is 0..14, and there is enough
+ * space, enter the shortcut and copy 16 bytes on behalf
+ * of the literals (in the fast mode, only 8 bytes can be
+ * safely copied this way).
+ * 2) Further if the match length is 4..18, copy 18 bytes
+ * in a similar manner; but we ensure that there's enough
+ * space in the output for those 18 bytes earlier, upon
+ * entering the shortcut (in other words, there is a
+ * combined check for both stages).
+ *
+ * The & in the likely() below is intentionally not && so that
+ * some compilers can produce better parallelized runtime code
+ */
+ if ((endOnInput ? length != RUN_MASK : length <= 8)
+ /*
+ * strictly "less than" on input, to re-enter
+ * the loop with at least one byte
+ */
+ && likely((endOnInput ? ip < shortiend : 1) &
+ (op <= shortoend))) {
+ /* Copy the literals */
+ LZ4_memcpy(op, ip, endOnInput ? 16 : 8);
+ op += length; ip += length;
+
+ /*
+ * The second stage:
+ * prepare for match copying, decode full info.
+ * If it doesn't work out, the info won't be wasted.
+ */
+ length = token & ML_MASK; /* match length */
+ offset = LZ4_readLE16(ip);
+ ip += 2;
+ match = op - offset;
+ assert(match <= op); /* check overflow */
+
+ /* Do not deal with overlapping matches. */
+ if ((length != ML_MASK) &&
+ (offset >= 8) &&
+ (dict == withPrefix64k || match >= lowPrefix)) {
+ /* Copy the match. */
+ LZ4_memcpy(op + 0, match + 0, 8);
+ LZ4_memcpy(op + 8, match + 8, 8);
+ LZ4_memcpy(op + 16, match + 16, 2);
+ op += length + MINMATCH;
+ /* Both stages worked, load the next token. */
+ continue;
+ }
+
+ /*
+ * The second stage didn't work out, but the info
+ * is ready. Propel it right to the point of match
+ * copying.
+ */
+ goto _copy_match;
+ }
+
+ /* decode literal length */
+ if (length == RUN_MASK) {
+ unsigned int s;
+
+ if (unlikely(endOnInput ? ip >= iend - RUN_MASK : 0)) {
+ /* overflow detection */
+ goto _output_error;
+ }
+ do {
+ s = *ip++;
+ length += s;
+ } while (likely(endOnInput
+ ? ip < iend - RUN_MASK
+ : 1) & (s == 255));
+
+ if ((safeDecode)
+ && unlikely((uptrval)(op) +
+ length < (uptrval)(op))) {
+ /* overflow detection */
+ goto _output_error;
+ }
+ if ((safeDecode)
+ && unlikely((uptrval)(ip) +
+ length < (uptrval)(ip))) {
+ /* overflow detection */
+ goto _output_error;
+ }
+ }
+
+ /* copy literals */
+ cpy = op + length;
+ LZ4_STATIC_ASSERT(MFLIMIT >= WILDCOPYLENGTH);
+
+ if (((endOnInput) && ((cpy > oend - MFLIMIT)
+ || (ip + length > iend - (2 + 1 + LASTLITERALS))))
+ || ((!endOnInput) && (cpy > oend - WILDCOPYLENGTH))) {
+ if (partialDecoding) {
+ if (cpy > oend) {
+ /*
+ * Partial decoding :
+ * stop in the middle of literal segment
+ */
+ cpy = oend;
+ length = oend - op;
+ }
+ if ((endOnInput)
+ && (ip + length > iend)) {
+ /*
+ * Error :
+ * read attempt beyond
+ * end of input buffer
+ */
+ goto _output_error;
+ }
+ } else {
+ if ((!endOnInput)
+ && (cpy != oend)) {
+ /*
+ * Error :
+ * block decoding must
+ * stop exactly there
+ */
+ goto _output_error;
+ }
+ if ((endOnInput)
+ && ((ip + length != iend)
+ || (cpy > oend))) {
+ /*
+ * Error :
+ * input must be consumed
+ */
+ goto _output_error;
+ }
+ }
+
+ /*
+ * supports overlapping memory regions; only matters
+ * for in-place decompression scenarios
+ */
+ LZ4_memmove(op, ip, length);
+ ip += length;
+ op += length;
+
+ /* Necessarily EOF when !partialDecoding.
+ * When partialDecoding, it is EOF if we've either
+ * filled the output buffer or
+ * can't proceed with reading an offset for following match.
+ */
+ if (!partialDecoding || (cpy == oend) || (ip >= (iend - 2)))
+ break;
+ } else {
+ /* may overwrite up to WILDCOPYLENGTH beyond cpy */
+ LZ4_wildCopy(op, ip, cpy);
+ ip += length;
+ op = cpy;
+ }
+
+ /* get offset */
+ offset = LZ4_readLE16(ip);
+ ip += 2;
+ match = op - offset;
+
+ /* get matchlength */
+ length = token & ML_MASK;
+
+_copy_match:
+ if ((checkOffset) && (unlikely(match + dictSize < lowPrefix))) {
+ /* Error : offset outside buffers */
+ goto _output_error;
+ }
+
+ /* costs ~1%; silence an msan warning when offset == 0 */
+ /*
+ * note : when partialDecoding, there is no guarantee that
+ * at least 4 bytes remain available in output buffer
+ */
+ if (!partialDecoding) {
+ assert(oend > op);
+ assert(oend - op >= 4);
+
+ LZ4_write32(op, (U32)offset);
+ }
+
+ if (length == ML_MASK) {
+ unsigned int s;
+
+ do {
+ s = *ip++;
+
+ if ((endOnInput) && (ip > iend - LASTLITERALS))
+ goto _output_error;
+
+ length += s;
+ } while (s == 255);
+
+ if ((safeDecode)
+ && unlikely(
+ (uptrval)(op) + length < (uptrval)op)) {
+ /* overflow detection */
+ goto _output_error;
+ }
+ }
+
+ length += MINMATCH;
+
+ /* match starting within external dictionary */
+ if ((dict == usingExtDict) && (match < lowPrefix)) {
+ if (unlikely(op + length > oend - LASTLITERALS)) {
+ /* doesn't respect parsing restriction */
+ if (!partialDecoding)
+ goto _output_error;
+ length = min(length, (size_t)(oend - op));
+ }
+
+ if (length <= (size_t)(lowPrefix - match)) {
+ /*
+ * match fits entirely within external
+ * dictionary : just copy
+ */
+ memmove(op, dictEnd - (lowPrefix - match),
+ length);
+ op += length;
+ } else {
+ /*
+ * match stretches into both external
+ * dictionary and current block
+ */
+ size_t const copySize = (size_t)(lowPrefix - match);
+ size_t const restSize = length - copySize;
+
+ LZ4_memcpy(op, dictEnd - copySize, copySize);
+ op += copySize;
+ if (restSize > (size_t)(op - lowPrefix)) {
+ /* overlap copy */
+ BYTE * const endOfMatch = op + restSize;
+ const BYTE *copyFrom = lowPrefix;
+
+ while (op < endOfMatch)
+ *op++ = *copyFrom++;
+ } else {
+ LZ4_memcpy(op, lowPrefix, restSize);
+ op += restSize;
+ }
+ }
+ continue;
+ }
+
+ /* copy match within block */
+ cpy = op + length;
+
+ /*
+ * partialDecoding :
+ * may not respect endBlock parsing restrictions
+ */
+ assert(op <= oend);
+ if (partialDecoding &&
+ (cpy > oend - MATCH_SAFEGUARD_DISTANCE)) {
+ size_t const mlen = min(length, (size_t)(oend - op));
+ const BYTE * const matchEnd = match + mlen;
+ BYTE * const copyEnd = op + mlen;
+
+ if (matchEnd > op) {
+ /* overlap copy */
+ while (op < copyEnd)
+ *op++ = *match++;
+ } else {
+ LZ4_memcpy(op, match, mlen);
+ }
+ op = copyEnd;
+ if (op == oend)
+ break;
+ continue;
+ }
+
+ if (unlikely(offset < 8)) {
+ op[0] = match[0];
+ op[1] = match[1];
+ op[2] = match[2];
+ op[3] = match[3];
+ match += inc32table[offset];
+ LZ4_memcpy(op + 4, match, 4);
+ match -= dec64table[offset];
+ } else {
+ LZ4_copy8(op, match);
+ match += 8;
+ }
+
+ op += 8;
+
+ if (unlikely(cpy > oend - MATCH_SAFEGUARD_DISTANCE)) {
+ BYTE * const oCopyLimit = oend - (WILDCOPYLENGTH - 1);
+
+ if (cpy > oend - LASTLITERALS) {
+ /*
+ * Error : last LASTLITERALS bytes
+ * must be literals (uncompressed)
+ */
+ goto _output_error;
+ }
+
+ if (op < oCopyLimit) {
+ LZ4_wildCopy(op, match, oCopyLimit);
+ match += oCopyLimit - op;
+ op = oCopyLimit;
+ }
+ while (op < cpy)
+ *op++ = *match++;
+ } else {
+ LZ4_copy8(op, match);
+ if (length > 16)
+ LZ4_wildCopy(op + 8, match + 8, cpy);
+ }
+ op = cpy; /* wildcopy correction */
+ }
+
+ /* end of decoding */
+ if (endOnInput) {
+ /* Nb of output bytes decoded */
+ return (int) (((char *)op) - dst);
+ } else {
+ /* Nb of input bytes read */
+ return (int) (((const char *)ip) - src);
+ }
+
+ /* Overflow error detected */
+_output_error:
+ return (int) (-(((const char *)ip) - src)) - 1;
+}
+
+int LZ4_decompress_safe(const char *source, char *dest,
+ int compressedSize, int maxDecompressedSize)
+{
+ return LZ4_decompress_generic(source, dest,
+ compressedSize, maxDecompressedSize,
+ endOnInputSize, decode_full_block,
+ noDict, (BYTE *)dest, NULL, 0);
+}
+
+int LZ4_decompress_safe_partial(const char *src, char *dst,
+ int compressedSize, int targetOutputSize, int dstCapacity)
+{
+ dstCapacity = min(targetOutputSize, dstCapacity);
+ return LZ4_decompress_generic(src, dst, compressedSize, dstCapacity,
+ endOnInputSize, partial_decode,
+ noDict, (BYTE *)dst, NULL, 0);
+}
+
+int LZ4_decompress_fast(const char *source, char *dest, int originalSize)
+{
+ return LZ4_decompress_generic(source, dest, 0, originalSize,
+ endOnOutputSize, decode_full_block,
+ withPrefix64k,
+ (BYTE *)dest - 64 * KB, NULL, 0);
+}
+
+/* ===== Instantiate a few more decoding cases, used more than once. ===== */
+
+static int LZ4_decompress_safe_withPrefix64k(const char *source, char *dest,
+ int compressedSize, int maxOutputSize)
+{
+ return LZ4_decompress_generic(source, dest,
+ compressedSize, maxOutputSize,
+ endOnInputSize, decode_full_block,
+ withPrefix64k,
+ (BYTE *)dest - 64 * KB, NULL, 0);
+}
+
+static int LZ4_decompress_safe_withSmallPrefix(const char *source, char *dest,
+ int compressedSize,
+ int maxOutputSize,
+ size_t prefixSize)
+{
+ return LZ4_decompress_generic(source, dest,
+ compressedSize, maxOutputSize,
+ endOnInputSize, decode_full_block,
+ noDict,
+ (BYTE *)dest - prefixSize, NULL, 0);
+}
+
+static int LZ4_decompress_safe_forceExtDict(const char *source, char *dest,
+ int compressedSize, int maxOutputSize,
+ const void *dictStart, size_t dictSize)
+{
+ return LZ4_decompress_generic(source, dest,
+ compressedSize, maxOutputSize,
+ endOnInputSize, decode_full_block,
+ usingExtDict, (BYTE *)dest,
+ (const BYTE *)dictStart, dictSize);
+}
+
+static int LZ4_decompress_fast_extDict(const char *source, char *dest,
+ int originalSize,
+ const void *dictStart, size_t dictSize)
+{
+ return LZ4_decompress_generic(source, dest,
+ 0, originalSize,
+ endOnOutputSize, decode_full_block,
+ usingExtDict, (BYTE *)dest,
+ (const BYTE *)dictStart, dictSize);
+}
+
+/*
+ * The "double dictionary" mode, for use with e.g. ring buffers: the first part
+ * of the dictionary is passed as prefix, and the second via dictStart + dictSize.
+ * These routines are used only once, in LZ4_decompress_*_continue().
+ */
+static FORCE_INLINE
+int LZ4_decompress_safe_doubleDict(const char *source, char *dest,
+ int compressedSize, int maxOutputSize,
+ size_t prefixSize,
+ const void *dictStart, size_t dictSize)
+{
+ return LZ4_decompress_generic(source, dest,
+ compressedSize, maxOutputSize,
+ endOnInputSize, decode_full_block,
+ usingExtDict, (BYTE *)dest - prefixSize,
+ (const BYTE *)dictStart, dictSize);
+}
+
+static FORCE_INLINE
+int LZ4_decompress_fast_doubleDict(const char *source, char *dest,
+ int originalSize, size_t prefixSize,
+ const void *dictStart, size_t dictSize)
+{
+ return LZ4_decompress_generic(source, dest,
+ 0, originalSize,
+ endOnOutputSize, decode_full_block,
+ usingExtDict, (BYTE *)dest - prefixSize,
+ (const BYTE *)dictStart, dictSize);
+}
+
+/* ===== streaming decompression functions ===== */
+
+int LZ4_setStreamDecode(LZ4_streamDecode_t *LZ4_streamDecode,
+ const char *dictionary, int dictSize)
+{
+ LZ4_streamDecode_t_internal *lz4sd =
+ &LZ4_streamDecode->internal_donotuse;
+
+ lz4sd->prefixSize = (size_t) dictSize;
+ lz4sd->prefixEnd = (const BYTE *) dictionary + dictSize;
+ lz4sd->externalDict = NULL;
+ lz4sd->extDictSize = 0;
+ return 1;
+}
+
+/*
+ * *_continue() :
+ * These decoding functions allow decompression of multiple blocks
+ * in "streaming" mode.
+ * Previously decoded blocks must still be available at the memory
+ * position where they were decoded.
+ * If it's not possible, save the relevant part of
+ * decoded data into a safe buffer,
+ * and indicate where it stands using LZ4_setStreamDecode()
+ */
+int LZ4_decompress_safe_continue(LZ4_streamDecode_t *LZ4_streamDecode,
+ const char *source, char *dest, int compressedSize, int maxOutputSize)
+{
+ LZ4_streamDecode_t_internal *lz4sd =
+ &LZ4_streamDecode->internal_donotuse;
+ int result;
+
+ if (lz4sd->prefixSize == 0) {
+ /* The first call, no dictionary yet. */
+ assert(lz4sd->extDictSize == 0);
+ result = LZ4_decompress_safe(source, dest,
+ compressedSize, maxOutputSize);
+ if (result <= 0)
+ return result;
+ lz4sd->prefixSize = result;
+ lz4sd->prefixEnd = (BYTE *)dest + result;
+ } else if (lz4sd->prefixEnd == (BYTE *)dest) {
+ /* They're rolling the current segment. */
+ if (lz4sd->prefixSize >= 64 * KB - 1)
+ result = LZ4_decompress_safe_withPrefix64k(source, dest,
+ compressedSize, maxOutputSize);
+ else if (lz4sd->extDictSize == 0)
+ result = LZ4_decompress_safe_withSmallPrefix(source,
+ dest, compressedSize, maxOutputSize,
+ lz4sd->prefixSize);
+ else
+ result = LZ4_decompress_safe_doubleDict(source, dest,
+ compressedSize, maxOutputSize,
+ lz4sd->prefixSize,
+ lz4sd->externalDict, lz4sd->extDictSize);
+ if (result <= 0)
+ return result;
+ lz4sd->prefixSize += result;
+ lz4sd->prefixEnd += result;
+ } else {
+ /*
+ * The buffer wraps around, or they're
+ * switching to another buffer.
+ */
+ lz4sd->extDictSize = lz4sd->prefixSize;
+ lz4sd->externalDict = lz4sd->prefixEnd - lz4sd->extDictSize;
+ result = LZ4_decompress_safe_forceExtDict(source, dest,
+ compressedSize, maxOutputSize,
+ lz4sd->externalDict, lz4sd->extDictSize);
+ if (result <= 0)
+ return result;
+ lz4sd->prefixSize = result;
+ lz4sd->prefixEnd = (BYTE *)dest + result;
+ }
+
+ return result;
+}
+
+int LZ4_decompress_fast_continue(LZ4_streamDecode_t *LZ4_streamDecode,
+ const char *source, char *dest, int originalSize)
+{
+ LZ4_streamDecode_t_internal *lz4sd = &LZ4_streamDecode->internal_donotuse;
+ int result;
+
+ if (lz4sd->prefixSize == 0) {
+ assert(lz4sd->extDictSize == 0);
+ result = LZ4_decompress_fast(source, dest, originalSize);
+ if (result <= 0)
+ return result;
+ lz4sd->prefixSize = originalSize;
+ lz4sd->prefixEnd = (BYTE *)dest + originalSize;
+ } else if (lz4sd->prefixEnd == (BYTE *)dest) {
+ if (lz4sd->prefixSize >= 64 * KB - 1 ||
+ lz4sd->extDictSize == 0)
+ result = LZ4_decompress_fast(source, dest,
+ originalSize);
+ else
+ result = LZ4_decompress_fast_doubleDict(source, dest,
+ originalSize, lz4sd->prefixSize,
+ lz4sd->externalDict, lz4sd->extDictSize);
+ if (result <= 0)
+ return result;
+ lz4sd->prefixSize += originalSize;
+ lz4sd->prefixEnd += originalSize;
+ } else {
+ lz4sd->extDictSize = lz4sd->prefixSize;
+ lz4sd->externalDict = lz4sd->prefixEnd - lz4sd->extDictSize;
+ result = LZ4_decompress_fast_extDict(source, dest,
+ originalSize, lz4sd->externalDict, lz4sd->extDictSize);
+ if (result <= 0)
+ return result;
+ lz4sd->prefixSize = originalSize;
+ lz4sd->prefixEnd = (BYTE *)dest + originalSize;
+ }
+ return result;
+}
+
+int LZ4_decompress_safe_usingDict(const char *source, char *dest,
+ int compressedSize, int maxOutputSize,
+ const char *dictStart, int dictSize)
+{
+ if (dictSize == 0)
+ return LZ4_decompress_safe(source, dest,
+ compressedSize, maxOutputSize);
+ if (dictStart+dictSize == dest) {
+ if (dictSize >= 64 * KB - 1)
+ return LZ4_decompress_safe_withPrefix64k(source, dest,
+ compressedSize, maxOutputSize);
+ return LZ4_decompress_safe_withSmallPrefix(source, dest,
+ compressedSize, maxOutputSize, dictSize);
+ }
+ return LZ4_decompress_safe_forceExtDict(source, dest,
+ compressedSize, maxOutputSize, dictStart, dictSize);
+}
+
+int LZ4_decompress_fast_usingDict(const char *source, char *dest,
+ int originalSize,
+ const char *dictStart, int dictSize)
+{
+ if (dictSize == 0 || dictStart + dictSize == dest)
+ return LZ4_decompress_fast(source, dest, originalSize);
+
+ return LZ4_decompress_fast_extDict(source, dest, originalSize,
+ dictStart, dictSize);
+}
+
+#ifndef STATIC
+EXPORT_SYMBOL(LZ4_decompress_safe);
+EXPORT_SYMBOL(LZ4_decompress_safe_partial);
+EXPORT_SYMBOL(LZ4_decompress_fast);
+EXPORT_SYMBOL(LZ4_setStreamDecode);
+EXPORT_SYMBOL(LZ4_decompress_safe_continue);
+EXPORT_SYMBOL(LZ4_decompress_fast_continue);
+EXPORT_SYMBOL(LZ4_decompress_safe_usingDict);
+EXPORT_SYMBOL(LZ4_decompress_fast_usingDict);
+
+MODULE_LICENSE("Dual BSD/GPL");
+MODULE_DESCRIPTION("LZ4 decompressor");
+#endif