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- /*
- * 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, due to parsing restrictions */
- if (!partialDecoding || (cpy == oend))
- 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. ===== */
- 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);
- }
- 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);
- }
- /*-******************************
- * 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");
- #endif
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