v4.19.13 snapshot.
diff --git a/lib/lz4/lz4_decompress.c b/lib/lz4/lz4_decompress.c
new file mode 100644
index 0000000..141734d
--- /dev/null
+++ b/lib/lz4/lz4_decompress.c
@@ -0,0 +1,508 @@
+/*
+ * 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
+ *******************************/
+/* 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 * const iend = ip + inputSize;
+
+ BYTE *op = (BYTE *) dest;
+ BYTE * const oend = op + outputSize;
+ BYTE *cpy;
+ BYTE *oexit = op + targetOutputSize;
+ const BYTE * const lowLimit = lowPrefix - dictSize;
+
+ const BYTE * const dictEnd = (const BYTE *)dictStart + dictSize;
+ static const unsigned int dec32table[] = { 0, 1, 2, 1, 4, 4, 4, 4 };
+ static 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;
+
+ if (length == RUN_MASK) {
+ unsigned int s;
+
+ 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;
+ }
+ if ((safeDecode)
+ && unlikely(
+ (size_t)(ip + length) < (size_t)(ip))) {
+ /* overflow detection */
+ goto _output_error;
+ }
+ }
+
+ /* copy literals */
+ cpy = op + length;
+ 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;
+ op += length;
+ /* Necessarily EOF, due to parsing restrictions */
+ break;
+ }
+
+ LZ4_wildCopy(op, ip, cpy);
+ ip += length;
+ op = cpy;
+
+ /* get offset */
+ offset = LZ4_readLE16(ip);
+ ip += 2;
+ match = op - offset;
+
+ 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) {
+ 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 += 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_copy8(op, match);
+ match += 8;
+ }
+
+ 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;
+ }
+
+ 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; /* correction */
+ }
+
+ /* end of decoding */
+ if (endOnInput) {
+ /* Nb of output bytes decoded */
+ return (int) (((char *)op) - dest);
+ } else {
+ /* Nb of input bytes read */
+ return (int) (((const char *)ip) - source);
+ }
+
+ /* Overflow error detected */
+_output_error:
+ return -1;
+}
+
+int LZ4_decompress_safe(const char *source, char *dest,
+ int compressedSize, int maxDecompressedSize)
+{
+ return LZ4_decompress_generic(source, dest, compressedSize,
+ maxDecompressedSize, endOnInputSize, full, 0,
+ noDict, (BYTE *)dest, NULL, 0);
+}
+
+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);
+}
+
+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);
+}
+
+int LZ4_setStreamDecode(LZ4_streamDecode_t *LZ4_streamDecode,
+ const char *dictionary, int dictSize)
+{
+ LZ4_streamDecode_t_internal *lz4sd = (LZ4_streamDecode_t_internal *) LZ4_streamDecode;
+
+ 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->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;
+ }
+
+ 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->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;
+ }
+
+ return result;
+}
+
+/*
+ * 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)
+{
+ 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);
+}
+
+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);
+}
+
+int LZ4_decompress_fast_usingDict(const char *source, char *dest,
+ int originalSize, const char *dictStart, int dictSize)
+{
+ return LZ4_decompress_usingDict_generic(source, dest, 0,
+ originalSize, 0, 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