contrib/zstd/lib/legacy/zstd_v04.c in extzstd-0.1.1 vs contrib/zstd/lib/legacy/zstd_v04.c in extzstd-0.2
- old
+ new
@@ -1,12 +1,13 @@
-/**
+/*
* Copyright (c) 2016-present, Yann Collet, Facebook, Inc.
* All rights reserved.
*
- * This source code is licensed under the BSD-style license found in the
- * LICENSE file in the root directory of this source tree. An additional grant
- * of patent rights can be found in the PATENTS file in the same directory.
+ * This source code is licensed under both the BSD-style license (found in the
+ * LICENSE file in the root directory of this source tree) and the GPLv2 (found
+ * in the COPYING file in the root directory of this source tree).
+ * You may select, at your option, one of the above-listed licenses.
*/
/*- Dependencies -*/
#include "zstd_v04.h"
@@ -735,20 +736,10 @@
MEM_STATIC size_t BIT_readBits(BIT_DStream_t* bitD, unsigned nbBits);
MEM_STATIC BIT_DStream_status BIT_reloadDStream(BIT_DStream_t* bitD);
MEM_STATIC unsigned BIT_endOfDStream(const BIT_DStream_t* bitD);
-/*
-* Start by invoking BIT_initDStream().
-* A chunk of the bitStream is then stored into a local register.
-* Local register size is 64-bits on 64-bits systems, 32-bits on 32-bits systems (size_t).
-* You can then retrieve bitFields stored into the local register, **in reverse order**.
-* Local register is manually filled from memory by the BIT_reloadDStream() method.
-* A reload guarantee a minimum of ((8*sizeof(size_t))-7) bits when its result is BIT_DStream_unfinished.
-* Otherwise, it can be less than that, so proceed accordingly.
-* Checking if DStream has reached its end can be performed with BIT_endOfDStream()
-*/
/******************************************
* unsafe API
******************************************/
@@ -758,11 +749,11 @@
/****************************************************************
* Helper functions
****************************************************************/
-MEM_STATIC unsigned BIT_highbit32 (register U32 val)
+MEM_STATIC unsigned BIT_highbit32 (U32 val)
{
# if defined(_MSC_VER) /* Visual */
unsigned long r=0;
_BitScanReverse ( &r, val );
return (unsigned) r;
@@ -814,34 +805,27 @@
bitD->start = (const char*)srcBuffer;
bitD->ptr = bitD->start;
bitD->bitContainer = *(const BYTE*)(bitD->start);
switch(srcSize)
{
- case 7: bitD->bitContainer += (size_t)(((const BYTE*)(bitD->start))[6]) << (sizeof(size_t)*8 - 16);
- case 6: bitD->bitContainer += (size_t)(((const BYTE*)(bitD->start))[5]) << (sizeof(size_t)*8 - 24);
- case 5: bitD->bitContainer += (size_t)(((const BYTE*)(bitD->start))[4]) << (sizeof(size_t)*8 - 32);
- case 4: bitD->bitContainer += (size_t)(((const BYTE*)(bitD->start))[3]) << 24;
- case 3: bitD->bitContainer += (size_t)(((const BYTE*)(bitD->start))[2]) << 16;
- case 2: bitD->bitContainer += (size_t)(((const BYTE*)(bitD->start))[1]) << 8;
- default:;
+ case 7: bitD->bitContainer += (size_t)(((const BYTE*)(bitD->start))[6]) << (sizeof(size_t)*8 - 16);/* fall-through */
+ case 6: bitD->bitContainer += (size_t)(((const BYTE*)(bitD->start))[5]) << (sizeof(size_t)*8 - 24);/* fall-through */
+ case 5: bitD->bitContainer += (size_t)(((const BYTE*)(bitD->start))[4]) << (sizeof(size_t)*8 - 32);/* fall-through */
+ case 4: bitD->bitContainer += (size_t)(((const BYTE*)(bitD->start))[3]) << 24; /* fall-through */
+ case 3: bitD->bitContainer += (size_t)(((const BYTE*)(bitD->start))[2]) << 16; /* fall-through */
+ case 2: bitD->bitContainer += (size_t)(((const BYTE*)(bitD->start))[1]) << 8; /* fall-through */
+ default: break;
}
contain32 = ((const BYTE*)srcBuffer)[srcSize-1];
if (contain32 == 0) return ERROR(GENERIC); /* endMark not present */
bitD->bitsConsumed = 8 - BIT_highbit32(contain32);
bitD->bitsConsumed += (U32)(sizeof(size_t) - srcSize)*8;
}
return srcSize;
}
-/*!BIT_lookBits
- * Provides next n bits from local register
- * local register is not modified (bits are still present for next read/look)
- * On 32-bits, maxNbBits==25
- * On 64-bits, maxNbBits==57
- * @return : value extracted
- */
MEM_STATIC size_t BIT_lookBits(BIT_DStream_t* bitD, U32 nbBits)
{
const U32 bitMask = sizeof(bitD->bitContainer)*8 - 1;
return ((bitD->bitContainer << (bitD->bitsConsumed & bitMask)) >> 1) >> ((bitMask-nbBits) & bitMask);
}
@@ -857,15 +841,10 @@
MEM_STATIC void BIT_skipBits(BIT_DStream_t* bitD, U32 nbBits)
{
bitD->bitsConsumed += nbBits;
}
-/*!BIT_readBits
- * Read next n bits from local register.
- * pay attention to not read more than nbBits contained into local register.
- * @return : extracted value.
- */
MEM_STATIC size_t BIT_readBits(BIT_DStream_t* bitD, U32 nbBits)
{
size_t value = BIT_lookBits(bitD, nbBits);
BIT_skipBits(bitD, nbBits);
return value;
@@ -880,12 +859,12 @@
return value;
}
MEM_STATIC BIT_DStream_status BIT_reloadDStream(BIT_DStream_t* bitD)
{
- if (bitD->bitsConsumed > (sizeof(bitD->bitContainer)*8)) /* should never happen */
- return BIT_DStream_overflow;
+ if (bitD->bitsConsumed > (sizeof(bitD->bitContainer)*8)) /* should never happen */
+ return BIT_DStream_overflow;
if (bitD->ptr >= bitD->start + sizeof(bitD->bitContainer))
{
bitD->ptr -= bitD->bitsConsumed >> 3;
bitD->bitsConsumed &= 7;
@@ -1008,60 +987,11 @@
static unsigned char FSE_decodeSymbol(FSE_DState_t* DStatePtr, BIT_DStream_t* bitD);
static unsigned FSE_endOfDState(const FSE_DState_t* DStatePtr);
-/*!
-Let's now decompose FSE_decompress_usingDTable() into its unitary components.
-You will decode FSE-encoded symbols from the bitStream,
-and also any other bitFields you put in, **in reverse order**.
-You will need a few variables to track your bitStream. They are :
-
-BIT_DStream_t DStream; // Stream context
-FSE_DState_t DState; // State context. Multiple ones are possible
-FSE_DTable* DTablePtr; // Decoding table, provided by FSE_buildDTable()
-
-The first thing to do is to init the bitStream.
- errorCode = BIT_initDStream(&DStream, srcBuffer, srcSize);
-
-You should then retrieve your initial state(s)
-(in reverse flushing order if you have several ones) :
- errorCode = FSE_initDState(&DState, &DStream, DTablePtr);
-
-You can then decode your data, symbol after symbol.
-For information the maximum number of bits read by FSE_decodeSymbol() is 'tableLog'.
-Keep in mind that symbols are decoded in reverse order, like a LIFO stack (last in, first out).
- unsigned char symbol = FSE_decodeSymbol(&DState, &DStream);
-
-You can retrieve any bitfield you eventually stored into the bitStream (in reverse order)
-Note : maximum allowed nbBits is 25, for 32-bits compatibility
- size_t bitField = BIT_readBits(&DStream, nbBits);
-
-All above operations only read from local register (which size depends on size_t).
-Refueling the register from memory is manually performed by the reload method.
- endSignal = FSE_reloadDStream(&DStream);
-
-BIT_reloadDStream() result tells if there is still some more data to read from DStream.
-BIT_DStream_unfinished : there is still some data left into the DStream.
-BIT_DStream_endOfBuffer : Dstream reached end of buffer. Its container may no longer be completely filled.
-BIT_DStream_completed : Dstream reached its exact end, corresponding in general to decompression completed.
-BIT_DStream_tooFar : Dstream went too far. Decompression result is corrupted.
-
-When reaching end of buffer (BIT_DStream_endOfBuffer), progress slowly, notably if you decode multiple symbols per loop,
-to properly detect the exact end of stream.
-After each decoded symbol, check if DStream is fully consumed using this simple test :
- BIT_reloadDStream(&DStream) >= BIT_DStream_completed
-
-When it's done, verify decompression is fully completed, by checking both DStream and the relevant states.
-Checking if DStream has reached its end is performed by :
- BIT_endOfDStream(&DStream);
-Check also the states. There might be some symbols left there, if some high probability ones (>50%) are possible.
- FSE_endOfDState(&DState);
-*/
-
-
/* *****************************************
* FSE unsafe API
*******************************************/
static unsigned char FSE_decodeSymbolFast(FSE_DState_t* DStatePtr, BIT_DStream_t* bitD);
/* faster, but works only if nbBits is always >= 1 (otherwise, result will be corrupted) */
@@ -1449,12 +1379,12 @@
bitCount &= 7;
}
else
{
bitCount -= (int)(8 * (iend - 4 - ip));
- ip = iend - 4;
- }
+ ip = iend - 4;
+ }
bitStream = MEM_readLE32(ip) >> (bitCount & 31);
}
}
}
if (remaining != 1) return ERROR(GENERIC);
@@ -2774,11 +2704,11 @@
static size_t ZSTD_decodeFrameHeader_Part2(ZSTD_DCtx* zc, const void* src, size_t srcSize)
{
size_t result;
if (srcSize != zc->headerSize) return ERROR(srcSize_wrong);
result = ZSTD_getFrameParams(&(zc->params), src, srcSize);
- if ((MEM_32bits()) && (zc->params.windowLog > 25)) return ERROR(frameParameter_unsupportedBy32bits);
+ if ((MEM_32bits()) && (zc->params.windowLog > 25)) return ERROR(frameParameter_unsupported);
return result;
}
static size_t ZSTD_getcBlockSize(const void* src, size_t srcSize, blockProperties_t* bpPtr)
@@ -3663,11 +3593,11 @@
zbc->hPos = 0;
zbc->stage = ZBUFFds_load;
break;
}
zbc->stage = ZBUFFds_read;
-
+ /* fall-through */
case ZBUFFds_read:
{
size_t neededInSize = ZSTD_nextSrcSizeToDecompress(zbc->zc);
if (neededInSize==0) /* end of frame */
{
@@ -3689,11 +3619,11 @@
break;
}
if (ip==iend) { notDone = 0; break; } /* no more input */
zbc->stage = ZBUFFds_load;
}
-
+ /* fall-through */
case ZBUFFds_load:
{
size_t neededInSize = ZSTD_nextSrcSizeToDecompress(zbc->zc);
size_t toLoad = neededInSize - zbc->inPos; /* should always be <= remaining space within inBuff */
size_t loadedSize;
@@ -3709,12 +3639,13 @@
if (ZSTD_isError(decodedSize)) return decodedSize;
zbc->inPos = 0; /* input is consumed */
if (!decodedSize) { zbc->stage = ZBUFFds_read; break; } /* this was just a header */
zbc->outEnd = zbc->outStart + decodedSize;
zbc->stage = ZBUFFds_flush;
- // break; /* ZBUFFds_flush follows */
+ /* ZBUFFds_flush follows */
}
}
+ /* fall-through */
case ZBUFFds_flush:
{
size_t toFlushSize = zbc->outEnd - zbc->outStart;
size_t flushedSize = ZBUFF_limitCopy(op, oend-op, zbc->outBuff + zbc->outStart, toFlushSize);
op += flushedSize;