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-rw-r--r--lib/lz4/lz4_decompress.c705
1 files changed, 456 insertions, 249 deletions
diff --git a/lib/lz4/lz4_decompress.c b/lib/lz4/lz4_decompress.c
index 6d940c72b5fc..b5e00a19a7b4 100644
--- a/lib/lz4/lz4_decompress.c
+++ b/lib/lz4/lz4_decompress.c
@@ -1,25 +1,16 @@
/*
- * LZ4 Decompressor for Linux kernel
- *
- * Copyright (C) 2013, LG Electronics, Kyungsik Lee <kyungsik.lee@lge.com>
- *
- * Based on LZ4 implementation by Yann Collet.
- *
* LZ4 - Fast LZ compression algorithm
- * Copyright (C) 2011-2012, Yann Collet.
- * BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php)
- *
+ * 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
+ * * 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
@@ -31,313 +22,529 @@
* 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
*
- * You can contact the author at :
- * - LZ4 homepage : http://fastcompression.blogspot.com/p/lz4.html
- * - LZ4 source repository : http://code.google.com/p/lz4/
+ * Changed for kernel usage by:
+ * Sven Schmidt <4sschmid@informatik.uni-hamburg.de>
*/
-#ifndef STATIC
+/*-************************************
+ * Dependencies
+ **************************************/
+#include <linux/lz4.h>
+#include "lz4defs.h"
+#include <linux/init.h>
#include <linux/module.h>
#include <linux/kernel.h>
-#endif
-#include <linux/lz4.h>
-
#include <asm/unaligned.h>
-#include "lz4defs.h"
-
-static const int dec32table[] = {0, 3, 2, 3, 0, 0, 0, 0};
-#if LZ4_ARCH64
-static const int dec64table[] = {0, 0, 0, -1, 0, 1, 2, 3};
-#endif
-
-static int lz4_uncompress(const char *source, char *dest, int osize)
+/*-*****************************
+ * Decompression functions
+ *******************************/
+/* LZ4_decompress_generic() :
+ * This generic decompression function cover all use cases.
+ * It shall be instantiated several times, using different sets of directives
+ * Note that it is important this generic function is really inlined,
+ * in order to remove useless branches during compilation optimization.
+ */
+static FORCE_INLINE int LZ4_decompress_generic(
+ const char * const source,
+ char * const dest,
+ int inputSize,
+ /*
+ * If endOnInput == endOnInputSize,
+ * this value is the max size of Output Buffer.
+ */
+ int outputSize,
+ /* endOnOutputSize, endOnInputSize */
+ int endOnInput,
+ /* full, partial */
+ int partialDecoding,
+ /* only used if partialDecoding == partial */
+ int targetOutputSize,
+ /* noDict, withPrefix64k, usingExtDict */
+ int dict,
+ /* == dest when no prefix */
+ const BYTE * const lowPrefix,
+ /* only if dict == usingExtDict */
+ const BYTE * const dictStart,
+ /* note : = 0 if noDict */
+ const size_t dictSize
+ )
{
+ /* Local Variables */
const BYTE *ip = (const BYTE *) source;
- const BYTE *ref;
+ const BYTE * const iend = ip + inputSize;
+
BYTE *op = (BYTE *) dest;
- BYTE * const oend = op + osize;
+ BYTE * const oend = op + outputSize;
BYTE *cpy;
- unsigned token;
- size_t length;
+ BYTE *oexit = op + targetOutputSize;
+ const BYTE * const lowLimit = lowPrefix - dictSize;
+
+ const BYTE * const dictEnd = (const BYTE *)dictStart + dictSize;
+ const unsigned int dec32table[] = { 0, 1, 2, 1, 4, 4, 4, 4 };
+ const int dec64table[] = { 0, 0, 0, -1, 0, 1, 2, 3 };
+ const int safeDecode = (endOnInput == endOnInputSize);
+ const int checkOffset = ((safeDecode) && (dictSize < (int)(64 * KB)));
+
+ /* Special cases */
+ /* targetOutputSize too high => decode everything */
+ if ((partialDecoding) && (oexit > oend - MFLIMIT))
+ oexit = oend - MFLIMIT;
+
+ /* Empty output buffer */
+ if ((endOnInput) && (unlikely(outputSize == 0)))
+ return ((inputSize == 1) && (*ip == 0)) ? 0 : -1;
+
+ if ((!endOnInput) && (unlikely(outputSize == 0)))
+ return (*ip == 0 ? 1 : -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;
- /* get runlength */
- token = *ip++;
- length = (token >> ML_BITS);
if (length == RUN_MASK) {
- size_t len;
+ unsigned int s;
- len = *ip++;
- for (; len == 255; length += 255)
- len = *ip++;
- if (unlikely(length > (size_t)(length + len)))
+ do {
+ s = *ip++;
+ length += s;
+ } while (likely(endOnInput
+ ? ip < iend - RUN_MASK
+ : 1) & (s == 255));
+
+ if ((safeDecode)
+ && unlikely(
+ (size_t)(op + length) < (size_t)(op))) {
+ /* overflow detection */
goto _output_error;
- length += len;
+ }
+ if ((safeDecode)
+ && unlikely(
+ (size_t)(ip + length) < (size_t)(ip))) {
+ /* overflow detection */
+ goto _output_error;
+ }
}
/* copy literals */
cpy = op + length;
- if (unlikely(cpy > oend - COPYLENGTH)) {
- /*
- * Error: not enough place for another match
- * (min 4) + 5 literals
- */
- if (cpy != oend)
- goto _output_error;
+ if (((endOnInput) && ((cpy > (partialDecoding ? oexit : oend - MFLIMIT))
+ || (ip + length > iend - (2 + 1 + LASTLITERALS))))
+ || ((!endOnInput) && (cpy > oend - WILDCOPYLENGTH))) {
+ if (partialDecoding) {
+ if (cpy > oend) {
+ /*
+ * Error :
+ * write attempt beyond end of output buffer
+ */
+ goto _output_error;
+ }
+ 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;
+ }
+ }
memcpy(op, ip, length);
ip += length;
- break; /* EOF */
+ op += length;
+ /* Necessarily EOF, due to parsing restrictions */
+ break;
}
- LZ4_WILDCOPY(ip, op, cpy);
- ip -= (op - cpy);
+
+ LZ4_wildCopy(op, ip, cpy);
+ ip += length;
op = cpy;
/* get offset */
- LZ4_READ_LITTLEENDIAN_16(ref, cpy, ip);
+ offset = LZ4_readLE16(ip);
ip += 2;
+ match = op - offset;
- /* Error: offset create reference outside destination buffer */
- if (unlikely(ref < (BYTE *const) dest))
+ if ((checkOffset) && (unlikely(match < lowLimit))) {
+ /* Error : offset outside buffers */
goto _output_error;
+ }
+
+ /* costs ~1%; silence an msan warning when offset == 0 */
+ LZ4_write32(op, (U32)offset);
/* get matchlength */
length = token & ML_MASK;
if (length == ML_MASK) {
- for (; *ip == 255; length += 255)
- ip++;
- if (unlikely(length > (size_t)(length + *ip)))
+ unsigned int s;
+
+ do {
+ s = *ip++;
+
+ if ((endOnInput) && (ip > iend - LASTLITERALS))
+ goto _output_error;
+
+ length += s;
+ } while (s == 255);
+
+ if ((safeDecode)
+ && unlikely(
+ (size_t)(op + length) < (size_t)op)) {
+ /* overflow detection */
goto _output_error;
- length += *ip++;
+ }
}
- /* copy repeated sequence */
- if (unlikely((op - ref) < STEPSIZE)) {
-#if LZ4_ARCH64
- int dec64 = dec64table[op - ref];
-#else
- const int dec64 = 0;
-#endif
- op[0] = ref[0];
- op[1] = ref[1];
- op[2] = ref[2];
- op[3] = ref[3];
- op += 4;
- ref += 4;
- ref -= dec32table[op-ref];
- PUT4(ref, op);
- op += STEPSIZE - 4;
- ref -= dec64;
+ length += MINMATCH;
+
+ /* check external dictionary */
+ if ((dict == usingExtDict) && (match < lowPrefix)) {
+ if (unlikely(op + length > oend - LASTLITERALS)) {
+ /* doesn't respect parsing restriction */
+ goto _output_error;
+ }
+
+ if (length <= (size_t)(lowPrefix - match)) {
+ /*
+ * match can be copied as a single segment
+ * from external dictionary
+ */
+ memmove(op, dictEnd - (lowPrefix - match),
+ length);
+ op += length;
+ } else {
+ /*
+ * match encompass external
+ * dictionary and current block
+ */
+ size_t const copySize = (size_t)(lowPrefix - match);
+ size_t const restSize = length - copySize;
+
+ 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 {
+ memcpy(op, lowPrefix, restSize);
+ op += restSize;
+ }
+ }
+
+ continue;
+ }
+
+ /* copy match within block */
+ cpy = op + length;
+
+ if (unlikely(offset < 8)) {
+ const int dec64 = dec64table[offset];
+
+ op[0] = match[0];
+ op[1] = match[1];
+ op[2] = match[2];
+ op[3] = match[3];
+ match += dec32table[offset];
+ memcpy(op + 4, match, 4);
+ match -= dec64;
} else {
- LZ4_COPYSTEP(ref, op);
+ LZ4_copy8(op, match);
+ match += 8;
}
- cpy = op + length - (STEPSIZE - 4);
- if (cpy > (oend - COPYLENGTH)) {
- /* Error: request to write beyond destination buffer */
- if (cpy > oend)
- goto _output_error;
-#if LZ4_ARCH64
- if ((ref + COPYLENGTH) > oend)
-#else
- if ((ref + COPYLENGTH) > oend ||
- (op + COPYLENGTH) > oend)
-#endif
+ op += 8;
+
+ if (unlikely(cpy > oend - 12)) {
+ BYTE * const oCopyLimit = oend - (WILDCOPYLENGTH - 1);
+
+ if (cpy > oend - LASTLITERALS) {
+ /*
+ * Error : last LASTLITERALS bytes
+ * must be literals (uncompressed)
+ */
goto _output_error;
- LZ4_SECURECOPY(ref, op, (oend - COPYLENGTH));
+ }
+
+ if (op < oCopyLimit) {
+ LZ4_wildCopy(op, match, oCopyLimit);
+ match += oCopyLimit - op;
+ op = oCopyLimit;
+ }
+
while (op < cpy)
- *op++ = *ref++;
- op = cpy;
- /*
- * Check EOF (should never happen, since last 5 bytes
- * are supposed to be literals)
- */
- if (op == oend)
- goto _output_error;
- continue;
+ *op++ = *match++;
+ } else {
+ LZ4_copy8(op, match);
+
+ if (length > 16)
+ LZ4_wildCopy(op + 8, match + 8, cpy);
}
- LZ4_SECURECOPY(ref, op, cpy);
+
op = cpy; /* correction */
}
+
/* end of decoding */
- return (int) (((char *)ip) - source);
+ if (endOnInput) {
+ /* Nb of output bytes decoded */
+ return (int) (((char *)op) - dest);
+ } else {
+ /* Nb of input bytes read */
+ return (int) (((const char *)ip) - source);
+ }
- /* write overflow error detected */
+ /* Overflow error detected */
_output_error:
return -1;
}
-static int lz4_uncompress_unknownoutputsize(const char *source, char *dest,
- int isize, size_t maxoutputsize)
+int LZ4_decompress_safe(const char *source, char *dest,
+ int compressedSize, int maxDecompressedSize)
{
- const BYTE *ip = (const BYTE *) source;
- const BYTE *const iend = ip + isize;
- const BYTE *ref;
-
+ return LZ4_decompress_generic(source, dest, compressedSize,
+ maxDecompressedSize, endOnInputSize, full, 0,
+ noDict, (BYTE *)dest, NULL, 0);
+}
- BYTE *op = (BYTE *) dest;
- BYTE * const oend = op + maxoutputsize;
- BYTE *cpy;
+int LZ4_decompress_safe_partial(const char *source, char *dest,
+ int compressedSize, int targetOutputSize, int maxDecompressedSize)
+{
+ return LZ4_decompress_generic(source, dest, compressedSize,
+ maxDecompressedSize, endOnInputSize, partial,
+ targetOutputSize, noDict, (BYTE *)dest, NULL, 0);
+}
- /* Main Loop */
- while (ip < iend) {
+int LZ4_decompress_fast(const char *source, char *dest, int originalSize)
+{
+ return LZ4_decompress_generic(source, dest, 0, originalSize,
+ endOnOutputSize, full, 0, withPrefix64k,
+ (BYTE *)(dest - 64 * KB), NULL, 64 * KB);
+}
- unsigned token;
- size_t length;
+int LZ4_setStreamDecode(LZ4_streamDecode_t *LZ4_streamDecode,
+ const char *dictionary, int dictSize)
+{
+ LZ4_streamDecode_t_internal *lz4sd = (LZ4_streamDecode_t_internal *) LZ4_streamDecode;
- /* get runlength */
- token = *ip++;
- length = (token >> ML_BITS);
- if (length == RUN_MASK) {
- int s = 255;
- while ((ip < iend) && (s == 255)) {
- s = *ip++;
- if (unlikely(length > (size_t)(length + s)))
- goto _output_error;
- length += s;
- }
- }
- /* copy literals */
- cpy = op + length;
- if ((cpy > oend - COPYLENGTH) ||
- (ip + length > iend - COPYLENGTH)) {
-
- if (cpy > oend)
- goto _output_error;/* writes beyond buffer */
-
- if (ip + length != iend)
- goto _output_error;/*
- * Error: LZ4 format requires
- * to consume all input
- * at this stage
- */
- memcpy(op, ip, length);
- op += length;
- break;/* Necessarily EOF, due to parsing restrictions */
- }
- LZ4_WILDCOPY(ip, op, cpy);
- ip -= (op - cpy);
- op = cpy;
+ lz4sd->prefixSize = (size_t) dictSize;
+ lz4sd->prefixEnd = (const BYTE *) dictionary + dictSize;
+ lz4sd->externalDict = NULL;
+ lz4sd->extDictSize = 0;
+ return 1;
+}
- /* get offset */
- LZ4_READ_LITTLEENDIAN_16(ref, cpy, ip);
- ip += 2;
- if (ref < (BYTE * const) dest)
- goto _output_error;
- /*
- * Error : offset creates reference
- * outside of destination buffer
- */
+/*
+ * *_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->prefixEnd == (BYTE *)dest) {
+ result = LZ4_decompress_generic(source, dest,
+ compressedSize,
+ maxOutputSize,
+ endOnInputSize, full, 0,
+ usingExtDict, lz4sd->prefixEnd - lz4sd->prefixSize,
+ lz4sd->externalDict,
+ lz4sd->extDictSize);
+
+ if (result <= 0)
+ return result;
+
+ lz4sd->prefixSize += result;
+ lz4sd->prefixEnd += result;
+ } else {
+ lz4sd->extDictSize = lz4sd->prefixSize;
+ lz4sd->externalDict = lz4sd->prefixEnd - lz4sd->extDictSize;
+ result = LZ4_decompress_generic(source, dest,
+ compressedSize, maxOutputSize,
+ endOnInputSize, full, 0,
+ usingExtDict, (BYTE *)dest,
+ lz4sd->externalDict, lz4sd->extDictSize);
+ if (result <= 0)
+ return result;
+ lz4sd->prefixSize = result;
+ lz4sd->prefixEnd = (BYTE *)dest + result;
+ }
- /* get matchlength */
- length = (token & ML_MASK);
- if (length == ML_MASK) {
- while (ip < iend) {
- int s = *ip++;
- if (unlikely(length > (size_t)(length + s)))
- goto _output_error;
- length += s;
- if (s == 255)
- continue;
- break;
- }
- }
+ return result;
+}
- /* copy repeated sequence */
- if (unlikely((op - ref) < STEPSIZE)) {
-#if LZ4_ARCH64
- int dec64 = dec64table[op - ref];
-#else
- const int dec64 = 0;
-#endif
- op[0] = ref[0];
- op[1] = ref[1];
- op[2] = ref[2];
- op[3] = ref[3];
- op += 4;
- ref += 4;
- ref -= dec32table[op - ref];
- PUT4(ref, op);
- op += STEPSIZE - 4;
- ref -= dec64;
- } else {
- LZ4_COPYSTEP(ref, op);
- }
- cpy = op + length - (STEPSIZE-4);
- if (cpy > oend - COPYLENGTH) {
- if (cpy > oend)
- goto _output_error; /* write outside of buf */
-#if LZ4_ARCH64
- if ((ref + COPYLENGTH) > oend)
-#else
- if ((ref + COPYLENGTH) > oend ||
- (op + COPYLENGTH) > oend)
-#endif
- goto _output_error;
- LZ4_SECURECOPY(ref, op, (oend - COPYLENGTH));
- while (op < cpy)
- *op++ = *ref++;
- op = cpy;
- /*
- * Check EOF (should never happen, since last 5 bytes
- * are supposed to be literals)
- */
- if (op == oend)
- goto _output_error;
- continue;
- }
- LZ4_SECURECOPY(ref, op, cpy);
- op = cpy; /* correction */
+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->prefixEnd == (BYTE *)dest) {
+ result = LZ4_decompress_generic(source, dest, 0, originalSize,
+ endOnOutputSize, full, 0,
+ usingExtDict,
+ lz4sd->prefixEnd - 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_generic(source, dest, 0, originalSize,
+ endOnOutputSize, full, 0,
+ usingExtDict, (BYTE *)dest,
+ lz4sd->externalDict, lz4sd->extDictSize);
+ if (result <= 0)
+ return result;
+ lz4sd->prefixSize = originalSize;
+ lz4sd->prefixEnd = (BYTE *)dest + originalSize;
}
- /* end of decoding */
- return (int) (((char *) op) - dest);
- /* write overflow error detected */
-_output_error:
- return -1;
+ return result;
}
-int lz4_decompress(const unsigned char *src, size_t *src_len,
- unsigned char *dest, size_t actual_dest_len)
+/*
+ * Advanced decoding functions :
+ * *_usingDict() :
+ * These decoding functions work the same as "_continue" ones,
+ * the dictionary must be explicitly provided within parameters
+ */
+static FORCE_INLINE int LZ4_decompress_usingDict_generic(const char *source,
+ char *dest, int compressedSize, int maxOutputSize, int safe,
+ const char *dictStart, int dictSize)
{
- int ret = -1;
- int input_len = 0;
-
- input_len = lz4_uncompress(src, dest, actual_dest_len);
- if (input_len < 0)
- goto exit_0;
- *src_len = input_len;
+ if (dictSize == 0)
+ return LZ4_decompress_generic(source, dest,
+ compressedSize, maxOutputSize, safe, full, 0,
+ noDict, (BYTE *)dest, NULL, 0);
+ if (dictStart + dictSize == dest) {
+ if (dictSize >= (int)(64 * KB - 1))
+ return LZ4_decompress_generic(source, dest,
+ compressedSize, maxOutputSize, safe, full, 0,
+ withPrefix64k, (BYTE *)dest - 64 * KB, NULL, 0);
+ return LZ4_decompress_generic(source, dest, compressedSize,
+ maxOutputSize, safe, full, 0, noDict,
+ (BYTE *)dest - dictSize, NULL, 0);
+ }
+ return LZ4_decompress_generic(source, dest, compressedSize,
+ maxOutputSize, safe, full, 0, usingExtDict,
+ (BYTE *)dest, (const BYTE *)dictStart, dictSize);
+}
- return 0;
-exit_0:
- return ret;
+int LZ4_decompress_safe_usingDict(const char *source, char *dest,
+ int compressedSize, int maxOutputSize,
+ const char *dictStart, int dictSize)
+{
+ return LZ4_decompress_usingDict_generic(source, dest,
+ compressedSize, maxOutputSize, 1, dictStart, dictSize);
}
-#ifndef STATIC
-EXPORT_SYMBOL(lz4_decompress);
-#endif
-int lz4_decompress_unknownoutputsize(const unsigned char *src, size_t src_len,
- unsigned char *dest, size_t *dest_len)
+int LZ4_decompress_fast_usingDict(const char *source, char *dest,
+ int originalSize, const char *dictStart, int dictSize)
{
- int ret = -1;
- int out_len = 0;
-
- out_len = lz4_uncompress_unknownoutputsize(src, dest, src_len,
- *dest_len);
- if (out_len < 0)
- goto exit_0;
- *dest_len = out_len;
-
- return 0;
-exit_0:
- return ret;
+ return LZ4_decompress_usingDict_generic(source, dest, 0,
+ originalSize, 0, dictStart, dictSize);
}
+
+/*-******************************
+ * For backwards compatibility
+ ********************************/
+int lz4_decompress_unknownoutputsize(const unsigned char *src,
+ size_t src_len, unsigned char *dest, size_t *dest_len) {
+ *dest_len = LZ4_decompress_safe(src, dest,
+ src_len, *dest_len);
+
+ /*
+ * Prior lz4_decompress_unknownoutputsize will return
+ * 0 for success and a negative result for error
+ * new LZ4_decompress_safe returns
+ * - the length of data read on success
+ * - and also a negative result on error
+ * meaning when result > 0, we just return 0 here
+ */
+ if (src_len > 0)
+ return 0;
+ else
+ return -1;
+}
+
+int lz4_decompress(const unsigned char *src, size_t *src_len,
+ unsigned char *dest, size_t actual_dest_len) {
+ *src_len = LZ4_decompress_fast(src, dest, actual_dest_len);
+
+ /*
+ * Prior lz4_decompress will return
+ * 0 for success and a negative result for error
+ * new LZ4_decompress_fast returns
+ * - the length of data read on success
+ * - and also a negative result on error
+ * meaning when result > 0, we just return 0 here
+ */
+ if (*src_len > 0)
+ return 0;
+ else
+ return -1;
+}
+
#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);
EXPORT_SYMBOL(lz4_decompress_unknownoutputsize);
+EXPORT_SYMBOL(lz4_decompress);
MODULE_LICENSE("Dual BSD/GPL");
-MODULE_DESCRIPTION("LZ4 Decompressor");
+MODULE_DESCRIPTION("LZ4 decompressor");
#endif