[GRASS-SVN] r72721 - grass/trunk/lib/gis
svn_grass at osgeo.org
svn_grass at osgeo.org
Sat May 19 10:05:28 PDT 2018
Author: mmetz
Date: 2018-05-19 10:05:28 -0700 (Sat, 19 May 2018)
New Revision: 72721
Modified:
grass/trunk/lib/gis/lz4.c
grass/trunk/lib/gis/lz4.h
Log:
libgis: update to lz4-1.8.2
Modified: grass/trunk/lib/gis/lz4.c
===================================================================
--- grass/trunk/lib/gis/lz4.c 2018-05-19 15:50:47 UTC (rev 72720)
+++ grass/trunk/lib/gis/lz4.c 2018-05-19 17:05:28 UTC (rev 72721)
@@ -69,9 +69,11 @@
* Prefer these methods in priority order (0 > 1 > 2)
*/
#ifndef LZ4_FORCE_MEMORY_ACCESS /* can be defined externally */
-# if defined(__GNUC__) && ( defined(__ARM_ARCH_6__) || defined(__ARM_ARCH_6J__) || defined(__ARM_ARCH_6K__) || defined(__ARM_ARCH_6Z__) || defined(__ARM_ARCH_6ZK__) || defined(__ARM_ARCH_6T2__) )
+# if defined(__GNUC__) && \
+ ( defined(__ARM_ARCH_6__) || defined(__ARM_ARCH_6J__) || defined(__ARM_ARCH_6K__) \
+ || defined(__ARM_ARCH_6Z__) || defined(__ARM_ARCH_6ZK__) || defined(__ARM_ARCH_6T2__) )
# define LZ4_FORCE_MEMORY_ACCESS 2
-# elif defined(__INTEL_COMPILER) || defined(__GNUC__)
+# elif (defined(__INTEL_COMPILER) && !defined(_WIN32)) || defined(__GNUC__)
# define LZ4_FORCE_MEMORY_ACCESS 1
# endif
#endif
@@ -80,14 +82,17 @@
* LZ4_FORCE_SW_BITCOUNT
* Define this parameter if your target system or compiler does not support hardware bit count
*/
-#if defined(_MSC_VER) && defined(_WIN32_WCE) /* Visual Studio for Windows CE does not support Hardware bit count */
+#if defined(_MSC_VER) && defined(_WIN32_WCE) /* Visual Studio for WinCE doesn't support Hardware bit count */
# define LZ4_FORCE_SW_BITCOUNT
#endif
+
/*-************************************
* Dependency
**************************************/
+#define LZ4_STATIC_LINKING_ONLY
+#define LZ4_DISABLE_DEPRECATE_WARNINGS /* due to LZ4_decompress_safe_withPrefix64k */
#include "lz4.h"
/* see also "memory routines" below */
@@ -101,22 +106,44 @@
# pragma warning(disable : 4293) /* disable: C4293: too large shift (32-bits) */
#endif /* _MSC_VER */
-#ifndef FORCE_INLINE
+#ifndef LZ4_FORCE_INLINE
# ifdef _MSC_VER /* Visual Studio */
-# define FORCE_INLINE static __forceinline
+# define LZ4_FORCE_INLINE static __forceinline
# else
# if defined (__cplusplus) || defined (__STDC_VERSION__) && __STDC_VERSION__ >= 199901L /* C99 */
# ifdef __GNUC__
-# define FORCE_INLINE static inline __attribute__((always_inline))
+# define LZ4_FORCE_INLINE static inline __attribute__((always_inline))
# else
-# define FORCE_INLINE static inline
+# define LZ4_FORCE_INLINE static inline
# endif
# else
-# define FORCE_INLINE static
+# define LZ4_FORCE_INLINE static
# endif /* __STDC_VERSION__ */
# endif /* _MSC_VER */
-#endif /* FORCE_INLINE */
+#endif /* LZ4_FORCE_INLINE */
+/* LZ4_FORCE_O2_GCC_PPC64LE and LZ4_FORCE_O2_INLINE_GCC_PPC64LE
+ * Gcc on ppc64le generates an unrolled SIMDized loop for LZ4_wildCopy,
+ * together with a simple 8-byte copy loop as a fall-back path.
+ * However, this optimization hurts the decompression speed by >30%,
+ * because the execution does not go to the optimized loop
+ * for typical compressible data, and all of the preamble checks
+ * before going to the fall-back path become useless overhead.
+ * This optimization happens only with the -O3 flag, and -O2 generates
+ * a simple 8-byte copy loop.
+ * With gcc on ppc64le, all of the LZ4_decompress_* and LZ4_wildCopy
+ * functions are annotated with __attribute__((optimize("O2"))),
+ * and also LZ4_wildCopy is forcibly inlined, so that the O2 attribute
+ * of LZ4_wildCopy does not affect the compression speed.
+ */
+#if defined(__PPC64__) && defined(__LITTLE_ENDIAN__) && defined(__GNUC__)
+# define LZ4_FORCE_O2_GCC_PPC64LE __attribute__((optimize("O2")))
+# define LZ4_FORCE_O2_INLINE_GCC_PPC64LE __attribute__((optimize("O2"))) LZ4_FORCE_INLINE
+#else
+# define LZ4_FORCE_O2_GCC_PPC64LE
+# define LZ4_FORCE_O2_INLINE_GCC_PPC64LE static
+#endif
+
#if (defined(__GNUC__) && (__GNUC__ >= 3)) || (defined(__INTEL_COMPILER) && (__INTEL_COMPILER >= 800)) || defined(__clang__)
# define expect(expr,value) (__builtin_expect ((expr),(value)) )
#else
@@ -123,8 +150,12 @@
# define expect(expr,value) (expr)
#endif
+#ifndef likely
#define likely(expr) expect((expr) != 0, 1)
+#endif
+#ifndef unlikely
#define unlikely(expr) expect((expr) != 0, 0)
+#endif
/*-************************************
@@ -131,10 +162,11 @@
* Memory routines
**************************************/
#include <stdlib.h> /* malloc, calloc, free */
-#define ALLOCATOR(n,s) calloc(n,s)
-#define FREEMEM free
+#define ALLOC(s) malloc(s)
+#define ALLOC_AND_ZERO(s) calloc(1,s)
+#define FREEMEM(p) free(p)
#include <string.h> /* memset, memcpy */
-#define MEM_INIT memset
+#define MEM_INIT(p,v,s) memset((p),(v),(s))
/*-************************************
@@ -247,19 +279,15 @@
}
}
-static void LZ4_copy8(void* dst, const void* src)
-{
- memcpy(dst,src,8);
-}
-
/* customized variant of memcpy, which can overwrite up to 8 bytes beyond dstEnd */
-static void LZ4_wildCopy(void* dstPtr, const void* srcPtr, void* dstEnd)
+LZ4_FORCE_O2_INLINE_GCC_PPC64LE
+void LZ4_wildCopy(void* dstPtr, const void* srcPtr, void* dstEnd)
{
BYTE* d = (BYTE*)dstPtr;
const BYTE* s = (const BYTE*)srcPtr;
BYTE* const e = (BYTE*)dstEnd;
- do { LZ4_copy8(d,s); d+=8; s+=8; } while (d<e);
+ do { memcpy(d,s,8); d+=8; s+=8; } while (d<e);
}
@@ -289,15 +317,24 @@
/*-************************************
* Error detection
**************************************/
-#define LZ4_STATIC_ASSERT(c) { enum { LZ4_static_assert = 1/(int)(!!(c)) }; } /* use only *after* variable declarations */
+#if defined(LZ4_DEBUG) && (LZ4_DEBUG>=1)
+# include <assert.h>
+#else
+# ifndef assert
+# define assert(condition) ((void)0)
+# endif
+#endif
+#define LZ4_STATIC_ASSERT(c) { enum { LZ4_static_assert = 1/(int)(!!(c)) }; } /* use after variable declarations */
+
#if defined(LZ4_DEBUG) && (LZ4_DEBUG>=2)
# include <stdio.h>
-# define DEBUGLOG(l, ...) { \
- if (l<=LZ4_DEBUG) { \
- fprintf(stderr, __FILE__ ": "); \
- fprintf(stderr, __VA_ARGS__); \
- fprintf(stderr, " \n"); \
+static int g_debuglog_enable = 1;
+# define DEBUGLOG(l, ...) { \
+ if ((g_debuglog_enable) && (l<=LZ4_DEBUG)) { \
+ fprintf(stderr, __FILE__ ": "); \
+ fprintf(stderr, __VA_ARGS__); \
+ fprintf(stderr, " \n"); \
} }
#else
# define DEBUGLOG(l, ...) {} /* disabled */
@@ -307,7 +344,7 @@
/*-************************************
* Common functions
**************************************/
-static unsigned LZ4_NbCommonBytes (register reg_t val)
+static unsigned LZ4_NbCommonBytes (reg_t val)
{
if (LZ4_isLittleEndian()) {
if (sizeof(val)==8) {
@@ -318,7 +355,14 @@
# elif (defined(__clang__) || (defined(__GNUC__) && (__GNUC__>=3))) && !defined(LZ4_FORCE_SW_BITCOUNT)
return (__builtin_ctzll((U64)val) >> 3);
# else
- static const int DeBruijnBytePos[64] = { 0, 0, 0, 0, 0, 1, 1, 2, 0, 3, 1, 3, 1, 4, 2, 7, 0, 2, 3, 6, 1, 5, 3, 5, 1, 3, 4, 4, 2, 5, 6, 7, 7, 0, 1, 2, 3, 3, 4, 6, 2, 6, 5, 5, 3, 4, 5, 6, 7, 1, 2, 4, 6, 4, 4, 5, 7, 2, 6, 5, 7, 6, 7, 7 };
+ static const int DeBruijnBytePos[64] = { 0, 0, 0, 0, 0, 1, 1, 2,
+ 0, 3, 1, 3, 1, 4, 2, 7,
+ 0, 2, 3, 6, 1, 5, 3, 5,
+ 1, 3, 4, 4, 2, 5, 6, 7,
+ 7, 0, 1, 2, 3, 3, 4, 6,
+ 2, 6, 5, 5, 3, 4, 5, 6,
+ 7, 1, 2, 4, 6, 4, 4, 5,
+ 7, 2, 6, 5, 7, 6, 7, 7 };
return DeBruijnBytePos[((U64)((val & -(long long)val) * 0x0218A392CDABBD3FULL)) >> 58];
# endif
} else /* 32 bits */ {
@@ -329,12 +373,15 @@
# elif (defined(__clang__) || (defined(__GNUC__) && (__GNUC__>=3))) && !defined(LZ4_FORCE_SW_BITCOUNT)
return (__builtin_ctz((U32)val) >> 3);
# else
- static const int DeBruijnBytePos[32] = { 0, 0, 3, 0, 3, 1, 3, 0, 3, 2, 2, 1, 3, 2, 0, 1, 3, 3, 1, 2, 2, 2, 2, 0, 3, 1, 2, 0, 1, 0, 1, 1 };
+ static const int DeBruijnBytePos[32] = { 0, 0, 3, 0, 3, 1, 3, 0,
+ 3, 2, 2, 1, 3, 2, 0, 1,
+ 3, 3, 1, 2, 2, 2, 2, 0,
+ 3, 1, 2, 0, 1, 0, 1, 1 };
return DeBruijnBytePos[((U32)((val & -(S32)val) * 0x077CB531U)) >> 27];
# endif
}
} else /* Big Endian CPU */ {
- if (sizeof(val)==8) {
+ if (sizeof(val)==8) { /* 64-bits */
# if defined(_MSC_VER) && defined(_WIN64) && !defined(LZ4_FORCE_SW_BITCOUNT)
unsigned long r = 0;
_BitScanReverse64( &r, val );
@@ -342,8 +389,11 @@
# elif (defined(__clang__) || (defined(__GNUC__) && (__GNUC__>=3))) && !defined(LZ4_FORCE_SW_BITCOUNT)
return (__builtin_clzll((U64)val) >> 3);
# else
+ static const U32 by32 = sizeof(val)*4; /* 32 on 64 bits (goal), 16 on 32 bits.
+ Just to avoid some static analyzer complaining about shift by 32 on 32-bits target.
+ Note that this code path is never triggered in 32-bits mode. */
unsigned r;
- if (!(val>>32)) { r=4; } else { r=0; val>>=32; }
+ if (!(val>>by32)) { r=4; } else { r=0; val>>=by32; }
if (!(val>>16)) { r+=2; val>>=8; } else { val>>=24; }
r += (!val);
return r;
@@ -366,12 +416,21 @@
}
#define STEPSIZE sizeof(reg_t)
-static unsigned LZ4_count(const BYTE* pIn, const BYTE* pMatch, const BYTE* pInLimit)
+LZ4_FORCE_INLINE
+unsigned LZ4_count(const BYTE* pIn, const BYTE* pMatch, const BYTE* pInLimit)
{
const BYTE* const pStart = pIn;
- while (likely(pIn<pInLimit-(STEPSIZE-1))) {
+ if (likely(pIn < pInLimit-(STEPSIZE-1))) {
reg_t const diff = LZ4_read_ARCH(pMatch) ^ LZ4_read_ARCH(pIn);
+ if (!diff) {
+ pIn+=STEPSIZE; pMatch+=STEPSIZE;
+ } else {
+ return LZ4_NbCommonBytes(diff);
+ } }
+
+ while (likely(pIn < pInLimit-(STEPSIZE-1))) {
+ reg_t const diff = LZ4_read_ARCH(pMatch) ^ LZ4_read_ARCH(pIn);
if (!diff) { pIn+=STEPSIZE; pMatch+=STEPSIZE; continue; }
pIn += LZ4_NbCommonBytes(diff);
return (unsigned)(pIn - pStart);
@@ -395,10 +454,33 @@
/*-************************************
* Local Structures and types
**************************************/
-typedef enum { notLimited = 0, limitedOutput = 1 } limitedOutput_directive;
-typedef enum { byPtr, byU32, byU16 } tableType_t;
+typedef enum { notLimited = 0, limitedOutput = 1, fillOutput = 2 } limitedOutput_directive;
+typedef enum { clearedTable = 0, byPtr, byU32, byU16 } tableType_t;
-typedef enum { noDict = 0, withPrefix64k, usingExtDict } dict_directive;
+/**
+ * This enum distinguishes several different modes of accessing previous
+ * content in the stream.
+ *
+ * - noDict : There is no preceding content.
+ * - withPrefix64k : Table entries up to ctx->dictSize before the current blob
+ * blob being compressed are valid and refer to the preceding
+ * content (of length ctx->dictSize), which is available
+ * contiguously preceding in memory the content currently
+ * being compressed.
+ * - usingExtDict : Like withPrefix64k, but the preceding content is somewhere
+ * else in memory, starting at ctx->dictionary with length
+ * ctx->dictSize.
+ * - usingDictCtx : Like usingExtDict, but everything concerning the preceding
+ * content is in a separate context, pointed to by
+ * ctx->dictCtx. ctx->dictionary, ctx->dictSize, and table
+ * entries in the current context that refer to positions
+ * preceding the beginning of the current compression are
+ * ignored. Instead, ctx->dictCtx->dictionary and ctx->dictCtx
+ * ->dictSize describe the location and size of the preceding
+ * content, and matches are found by looking in the ctx
+ * ->dictCtx->hashTable.
+ */
+typedef enum { noDict = 0, withPrefix64k, usingExtDict, usingDictCtx } dict_directive;
typedef enum { noDictIssue = 0, dictSmall } dictIssue_directive;
typedef enum { endOnOutputSize = 0, endOnInputSize = 1 } endCondition_directive;
@@ -436,16 +518,31 @@
return (U32)(((sequence >> 24) * prime8bytes) >> (64 - hashLog));
}
-FORCE_INLINE U32 LZ4_hashPosition(const void* const p, tableType_t const tableType)
+LZ4_FORCE_INLINE U32 LZ4_hashPosition(const void* const p, tableType_t const tableType)
{
if ((sizeof(reg_t)==8) && (tableType != byU16)) return LZ4_hash5(LZ4_read_ARCH(p), tableType);
return LZ4_hash4(LZ4_read32(p), tableType);
}
-static void LZ4_putPositionOnHash(const BYTE* p, U32 h, void* tableBase, tableType_t const tableType, const BYTE* srcBase)
+static void LZ4_putIndexOnHash(U32 idx, U32 h, void* tableBase, tableType_t const tableType)
{
switch (tableType)
{
+ default: /* fallthrough */
+ case clearedTable: /* fallthrough */
+ case byPtr: { /* illegal! */ assert(0); return; }
+ case byU32: { U32* hashTable = (U32*) tableBase; hashTable[h] = idx; return; }
+ case byU16: { U16* hashTable = (U16*) tableBase; assert(idx < 65536); hashTable[h] = (U16)idx; return; }
+ }
+}
+
+static void LZ4_putPositionOnHash(const BYTE* p, U32 h,
+ void* tableBase, tableType_t const tableType,
+ const BYTE* srcBase)
+{
+ switch (tableType)
+ {
+ case clearedTable: { /* illegal! */ assert(0); return; }
case byPtr: { const BYTE** hashTable = (const BYTE**)tableBase; hashTable[h] = p; return; }
case byU32: { U32* hashTable = (U32*) tableBase; hashTable[h] = (U32)(p-srcBase); return; }
case byU16: { U16* hashTable = (U16*) tableBase; hashTable[h] = (U16)(p-srcBase); return; }
@@ -452,78 +549,160 @@
}
}
-FORCE_INLINE void LZ4_putPosition(const BYTE* p, void* tableBase, tableType_t tableType, const BYTE* srcBase)
+LZ4_FORCE_INLINE void LZ4_putPosition(const BYTE* p, void* tableBase, tableType_t tableType, const BYTE* srcBase)
{
U32 const h = LZ4_hashPosition(p, tableType);
LZ4_putPositionOnHash(p, h, tableBase, tableType, srcBase);
}
-static const BYTE* LZ4_getPositionOnHash(U32 h, void* tableBase, tableType_t tableType, const BYTE* srcBase)
+/* LZ4_getIndexOnHash() :
+ * Index of match position registered in hash table.
+ * hash position must be calculated by using base+index, or dictBase+index.
+ * Assumption 1 : only valid if tableType == byU32 or byU16.
+ * Assumption 2 : h is presumed valid (within limits of hash table)
+ */
+static U32 LZ4_getIndexOnHash(U32 h, const void* tableBase, tableType_t tableType)
{
- if (tableType == byPtr) { const BYTE** hashTable = (const BYTE**) tableBase; return hashTable[h]; }
- if (tableType == byU32) { const U32* const hashTable = (U32*) tableBase; return hashTable[h] + srcBase; }
- { const U16* const hashTable = (U16*) tableBase; return hashTable[h] + srcBase; } /* default, to ensure a return */
+ LZ4_STATIC_ASSERT(LZ4_MEMORY_USAGE > 2);
+ if (tableType == byU32) {
+ const U32* const hashTable = (const U32*) tableBase;
+ assert(h < (1U << (LZ4_MEMORY_USAGE-2)));
+ return hashTable[h];
+ }
+ if (tableType == byU16) {
+ const U16* const hashTable = (const U16*) tableBase;
+ assert(h < (1U << (LZ4_MEMORY_USAGE-1)));
+ return hashTable[h];
+ }
+ assert(0); return 0; /* forbidden case */
}
-FORCE_INLINE const BYTE* LZ4_getPosition(const BYTE* p, void* tableBase, tableType_t tableType, const BYTE* srcBase)
+static const BYTE* LZ4_getPositionOnHash(U32 h, const void* tableBase, tableType_t tableType, const BYTE* srcBase)
{
+ if (tableType == byPtr) { const BYTE* const* hashTable = (const BYTE* const*) tableBase; return hashTable[h]; }
+ if (tableType == byU32) { const U32* const hashTable = (const U32*) tableBase; return hashTable[h] + srcBase; }
+ { const U16* const hashTable = (const U16*) tableBase; return hashTable[h] + srcBase; } /* default, to ensure a return */
+}
+
+LZ4_FORCE_INLINE const BYTE* LZ4_getPosition(const BYTE* p,
+ const void* tableBase, tableType_t tableType,
+ const BYTE* srcBase)
+{
U32 const h = LZ4_hashPosition(p, tableType);
return LZ4_getPositionOnHash(h, tableBase, tableType, srcBase);
}
+LZ4_FORCE_INLINE void LZ4_prepareTable(
+ LZ4_stream_t_internal* const cctx,
+ const int inputSize,
+ const tableType_t tableType) {
+ /* If the table hasn't been used, it's guaranteed to be zeroed out, and is
+ * therefore safe to use no matter what mode we're in. Otherwise, we figure
+ * out if it's safe to leave as is or whether it needs to be reset.
+ */
+ if (cctx->tableType != clearedTable) {
+ if (cctx->tableType != tableType
+ || (tableType == byU16 && cctx->currentOffset + inputSize >= 0xFFFFU)
+ || (tableType == byU32 && cctx->currentOffset > 1 GB)
+ || tableType == byPtr
+ || inputSize >= 4 KB)
+ {
+ DEBUGLOG(4, "LZ4_prepareTable: Resetting table in %p", cctx);
+ MEM_INIT(cctx->hashTable, 0, LZ4_HASHTABLESIZE);
+ cctx->currentOffset = 0;
+ cctx->tableType = clearedTable;
+ } else {
+ DEBUGLOG(4, "LZ4_prepareTable: Re-use hash table (no reset)");
+ }
+ }
+ /* Adding a gap, so all previous entries are > MAX_DISTANCE back, is faster
+ * than compressing without a gap. However, compressing with
+ * currentOffset == 0 is faster still, so we preserve that case.
+ */
+ if (cctx->currentOffset != 0 && tableType == byU32) {
+ DEBUGLOG(5, "LZ4_prepareTable: adding 64KB to currentOffset");
+ cctx->currentOffset += 64 KB;
+ }
+
+ /* Finally, clear history */
+ cctx->dictCtx = NULL;
+ cctx->dictionary = NULL;
+ cctx->dictSize = 0;
+}
+
/** LZ4_compress_generic() :
inlined, to ensure branches are decided at compilation time */
-FORCE_INLINE int LZ4_compress_generic(
+LZ4_FORCE_INLINE int LZ4_compress_generic(
LZ4_stream_t_internal* const cctx,
const char* const source,
char* const dest,
const int inputSize,
+ int *inputConsumed, /* only written when outputLimited == fillOutput */
const int maxOutputSize,
const limitedOutput_directive outputLimited,
const tableType_t tableType,
- const dict_directive dict,
+ const dict_directive dictDirective,
const dictIssue_directive dictIssue,
const U32 acceleration)
{
const BYTE* ip = (const BYTE*) source;
- const BYTE* base;
+
+ U32 const startIndex = cctx->currentOffset;
+ const BYTE* base = (const BYTE*) source - startIndex;
const BYTE* lowLimit;
- const BYTE* const lowRefLimit = ip - cctx->dictSize;
- const BYTE* const dictionary = cctx->dictionary;
- const BYTE* const dictEnd = dictionary + cctx->dictSize;
- const ptrdiff_t dictDelta = dictEnd - (const BYTE*)source;
+
+ const LZ4_stream_t_internal* dictCtx = (const LZ4_stream_t_internal*) cctx->dictCtx;
+ const BYTE* const dictionary =
+ dictDirective == usingDictCtx ? dictCtx->dictionary : cctx->dictionary;
+ const U32 dictSize =
+ dictDirective == usingDictCtx ? dictCtx->dictSize : cctx->dictSize;
+ const U32 dictDelta = (dictDirective == usingDictCtx) ? startIndex - dictCtx->currentOffset : 0; /* make indexes in dictCtx comparable with index in current context */
+
+ int const maybe_extMem = (dictDirective == usingExtDict) || (dictDirective == usingDictCtx);
+ U32 const prefixIdxLimit = startIndex - dictSize; /* used when dictDirective == dictSmall */
+ const BYTE* const dictEnd = dictionary + dictSize;
const BYTE* anchor = (const BYTE*) source;
const BYTE* const iend = ip + inputSize;
- const BYTE* const mflimit = iend - MFLIMIT;
+ const BYTE* const mflimitPlusOne = iend - MFLIMIT + 1;
const BYTE* const matchlimit = iend - LASTLITERALS;
+ /* the dictCtx currentOffset is indexed on the start of the dictionary,
+ * while a dictionary in the current context precedes the currentOffset */
+ const BYTE* dictBase = dictDirective == usingDictCtx ?
+ dictionary + dictSize - dictCtx->currentOffset :
+ dictionary + dictSize - startIndex;
+
BYTE* op = (BYTE*) dest;
BYTE* const olimit = op + maxOutputSize;
+ U32 offset = 0;
U32 forwardH;
+ DEBUGLOG(5, "LZ4_compress_generic: srcSize=%i, tableType=%u", inputSize, tableType);
/* Init conditions */
+ if (outputLimited == fillOutput && maxOutputSize < 1) return 0; /* Impossible to store anything */
if ((U32)inputSize > (U32)LZ4_MAX_INPUT_SIZE) return 0; /* Unsupported inputSize, too large (or negative) */
- switch(dict)
- {
- case noDict:
- default:
- base = (const BYTE*)source;
- lowLimit = (const BYTE*)source;
- break;
- case withPrefix64k:
- base = (const BYTE*)source - cctx->currentOffset;
- lowLimit = (const BYTE*)source - cctx->dictSize;
- break;
- case usingExtDict:
- base = (const BYTE*)source - cctx->currentOffset;
- lowLimit = (const BYTE*)source;
- break;
+ if ((tableType == byU16) && (inputSize>=LZ4_64Klimit)) return 0; /* Size too large (not within 64K limit) */
+ if (tableType==byPtr) assert(dictDirective==noDict); /* only supported use case with byPtr */
+ assert(acceleration >= 1);
+
+ lowLimit = (const BYTE*)source - (dictDirective == withPrefix64k ? dictSize : 0);
+
+ /* Update context state */
+ if (dictDirective == usingDictCtx) {
+ /* Subsequent linked blocks can't use the dictionary. */
+ /* Instead, they use the block we just compressed. */
+ cctx->dictCtx = NULL;
+ cctx->dictSize = (U32)inputSize;
+ } else {
+ cctx->dictSize += (U32)inputSize;
}
- if ((tableType == byU16) && (inputSize>=LZ4_64Klimit)) return 0; /* Size too large (not within 64K limit) */
- if (inputSize<LZ4_minLength) goto _last_literals; /* Input too small, no compression (all literals) */
+ cctx->currentOffset += (U32)inputSize;
+ cctx->tableType = tableType;
+ if (inputSize<LZ4_minLength) goto _last_literals; /* Input too small, no compression (all literals) */
+
/* First Byte */
LZ4_putPosition(ip, cctx->hashTable, tableType, base);
ip++; forwardH = LZ4_hashPosition(ip, tableType);
@@ -530,12 +709,12 @@
/* Main Loop */
for ( ; ; ) {
- ptrdiff_t refDelta = 0;
const BYTE* match;
BYTE* token;
/* Find a match */
- { const BYTE* forwardIp = ip;
+ if (tableType == byPtr) {
+ const BYTE* forwardIp = ip;
unsigned step = 1;
unsigned searchMatchNb = acceleration << LZ4_skipTrigger;
do {
@@ -544,34 +723,89 @@
forwardIp += step;
step = (searchMatchNb++ >> LZ4_skipTrigger);
- if (unlikely(forwardIp > mflimit)) goto _last_literals;
+ if (unlikely(forwardIp > mflimitPlusOne)) goto _last_literals;
+ assert(ip < mflimitPlusOne);
match = LZ4_getPositionOnHash(h, cctx->hashTable, tableType, base);
- if (dict==usingExtDict) {
- if (match < (const BYTE*)source) {
- refDelta = dictDelta;
+ forwardH = LZ4_hashPosition(forwardIp, tableType);
+ LZ4_putPositionOnHash(ip, h, cctx->hashTable, tableType, base);
+
+ } while ( (match+MAX_DISTANCE < ip)
+ || (LZ4_read32(match) != LZ4_read32(ip)) );
+
+ } else { /* byU32, byU16 */
+
+ const BYTE* forwardIp = ip;
+ unsigned step = 1;
+ unsigned searchMatchNb = acceleration << LZ4_skipTrigger;
+ do {
+ U32 const h = forwardH;
+ U32 const current = (U32)(forwardIp - base);
+ U32 matchIndex = LZ4_getIndexOnHash(h, cctx->hashTable, tableType);
+ assert(matchIndex <= current);
+ assert(forwardIp - base < (ptrdiff_t)(2 GB - 1));
+ ip = forwardIp;
+ forwardIp += step;
+ step = (searchMatchNb++ >> LZ4_skipTrigger);
+
+ if (unlikely(forwardIp > mflimitPlusOne)) goto _last_literals;
+ assert(ip < mflimitPlusOne);
+
+ if (dictDirective == usingDictCtx) {
+ if (matchIndex < startIndex) {
+ /* there was no match, try the dictionary */
+ assert(tableType == byU32);
+ matchIndex = LZ4_getIndexOnHash(h, dictCtx->hashTable, byU32);
+ match = dictBase + matchIndex;
+ matchIndex += dictDelta; /* make dictCtx index comparable with current context */
lowLimit = dictionary;
} else {
- refDelta = 0;
+ match = base + matchIndex;
lowLimit = (const BYTE*)source;
- } }
+ }
+ } else if (dictDirective==usingExtDict) {
+ if (matchIndex < startIndex) {
+ DEBUGLOG(7, "extDict candidate: matchIndex=%5u < startIndex=%5u", matchIndex, startIndex);
+ assert(startIndex - matchIndex >= MINMATCH);
+ match = dictBase + matchIndex;
+ lowLimit = dictionary;
+ } else {
+ match = base + matchIndex;
+ lowLimit = (const BYTE*)source;
+ }
+ } else { /* single continuous memory segment */
+ match = base + matchIndex;
+ }
forwardH = LZ4_hashPosition(forwardIp, tableType);
- LZ4_putPositionOnHash(ip, h, cctx->hashTable, tableType, base);
+ LZ4_putIndexOnHash(current, h, cctx->hashTable, tableType);
- } while ( ((dictIssue==dictSmall) ? (match < lowRefLimit) : 0)
- || ((tableType==byU16) ? 0 : (match + MAX_DISTANCE < ip))
- || (LZ4_read32(match+refDelta) != LZ4_read32(ip)) );
+ if ((dictIssue == dictSmall) && (matchIndex < prefixIdxLimit)) continue; /* match outside of valid area */
+ assert(matchIndex < current);
+ if ((tableType != byU16) && (matchIndex+MAX_DISTANCE < current)) continue; /* too far */
+ if (tableType == byU16) assert((current - matchIndex) <= MAX_DISTANCE); /* too_far presumed impossible with byU16 */
+
+ if (LZ4_read32(match) == LZ4_read32(ip)) {
+ if (maybe_extMem) offset = current - matchIndex;
+ break; /* match found */
+ }
+
+ } while(1);
}
/* Catch up */
- while (((ip>anchor) & (match+refDelta > lowLimit)) && (unlikely(ip[-1]==match[refDelta-1]))) { ip--; match--; }
+ while (((ip>anchor) & (match > lowLimit)) && (unlikely(ip[-1]==match[-1]))) { ip--; match--; }
/* Encode Literals */
{ unsigned const litLength = (unsigned)(ip - anchor);
token = op++;
- if ((outputLimited) && /* Check output buffer overflow */
+ if ((outputLimited == limitedOutput) && /* Check output buffer overflow */
(unlikely(op + litLength + (2 + 1 + LASTLITERALS) + (litLength/255) > olimit)))
return 0;
+ if ((outputLimited == fillOutput) &&
+ (unlikely(op + (litLength+240)/255 /* litlen */ + litLength /* literals */ + 2 /* offset */ + 1 /* token */ + MFLIMIT - MINMATCH /* min last literals so last match is <= end - MFLIMIT */ > olimit))) {
+ op--;
+ goto _last_literals;
+ }
if (litLength >= RUN_MASK) {
int len = (int)litLength-RUN_MASK;
*token = (RUN_MASK<<ML_BITS);
@@ -583,40 +817,79 @@
/* Copy Literals */
LZ4_wildCopy(op, anchor, op+litLength);
op+=litLength;
+ DEBUGLOG(6, "seq.start:%i, literals=%u, match.start:%i",
+ (int)(anchor-(const BYTE*)source), litLength, (int)(ip-(const BYTE*)source));
}
_next_match:
+ /* at this stage, the following variables must be correctly set :
+ * - ip : at start of LZ operation
+ * - match : at start of previous pattern occurence; can be within current prefix, or within extDict
+ * - offset : if maybe_ext_memSegment==1 (constant)
+ * - lowLimit : must be == dictionary to mean "match is within extDict"; must be == source otherwise
+ * - token and *token : position to write 4-bits for match length; higher 4-bits for literal length supposed already written
+ */
+
+ if ((outputLimited == fillOutput) &&
+ (op + 2 /* offset */ + 1 /* token */ + MFLIMIT - MINMATCH /* min last literals so last match is <= end - MFLIMIT */ > olimit)) {
+ /* the match was too close to the end, rewind and go to last literals */
+ op = token;
+ goto _last_literals;
+ }
+
/* Encode Offset */
- LZ4_writeLE16(op, (U16)(ip-match)); op+=2;
+ if (maybe_extMem) { /* static test */
+ DEBUGLOG(6, " with offset=%u (ext if > %i)", offset, (int)(ip - (const BYTE*)source));
+ assert(offset <= MAX_DISTANCE && offset > 0);
+ LZ4_writeLE16(op, (U16)offset); op+=2;
+ } else {
+ DEBUGLOG(6, " with offset=%u (same segment)", (U32)(ip - match));
+ assert(ip-match <= MAX_DISTANCE);
+ LZ4_writeLE16(op, (U16)(ip - match)); op+=2;
+ }
/* Encode MatchLength */
{ unsigned matchCode;
- if ((dict==usingExtDict) && (lowLimit==dictionary)) {
- const BYTE* limit;
- match += refDelta;
- limit = ip + (dictEnd-match);
+ if ( (dictDirective==usingExtDict || dictDirective==usingDictCtx)
+ && (lowLimit==dictionary) /* match within extDict */ ) {
+ const BYTE* limit = ip + (dictEnd-match);
+ assert(dictEnd > match);
if (limit > matchlimit) limit = matchlimit;
matchCode = LZ4_count(ip+MINMATCH, match+MINMATCH, limit);
ip += MINMATCH + matchCode;
if (ip==limit) {
- unsigned const more = LZ4_count(ip, (const BYTE*)source, matchlimit);
+ unsigned const more = LZ4_count(limit, (const BYTE*)source, matchlimit);
matchCode += more;
ip += more;
}
+ DEBUGLOG(6, " with matchLength=%u starting in extDict", matchCode+MINMATCH);
} else {
matchCode = LZ4_count(ip+MINMATCH, match+MINMATCH, matchlimit);
ip += MINMATCH + matchCode;
+ DEBUGLOG(6, " with matchLength=%u", matchCode+MINMATCH);
}
- if ( outputLimited && /* Check output buffer overflow */
- (unlikely(op + (1 + LASTLITERALS) + (matchCode>>8) > olimit)) )
- return 0;
+ if ((outputLimited) && /* Check output buffer overflow */
+ (unlikely(op + (1 + LASTLITERALS) + (matchCode>>8) > olimit)) ) {
+ if (outputLimited == limitedOutput)
+ return 0;
+ if (outputLimited == fillOutput) {
+ /* Match description too long : reduce it */
+ U32 newMatchCode = 15 /* in token */ - 1 /* to avoid needing a zero byte */ + ((U32)(olimit - op) - 2 - 1 - LASTLITERALS) * 255;
+ ip -= matchCode - newMatchCode;
+ matchCode = newMatchCode;
+ }
+ }
if (matchCode >= ML_MASK) {
*token += ML_MASK;
matchCode -= ML_MASK;
LZ4_write32(op, 0xFFFFFFFF);
- while (matchCode >= 4*255) op+=4, LZ4_write32(op, 0xFFFFFFFF), matchCode -= 4*255;
+ while (matchCode >= 4*255) {
+ op+=4;
+ LZ4_write32(op, 0xFFFFFFFF);
+ matchCode -= 4*255;
+ }
op += matchCode / 255;
*op++ = (BYTE)(matchCode % 255);
} else
@@ -626,37 +899,80 @@
anchor = ip;
/* Test end of chunk */
- if (ip > mflimit) break;
+ if (ip >= mflimitPlusOne) break;
/* Fill table */
LZ4_putPosition(ip-2, cctx->hashTable, tableType, base);
/* Test next position */
- match = LZ4_getPosition(ip, cctx->hashTable, tableType, base);
- if (dict==usingExtDict) {
- if (match < (const BYTE*)source) {
- refDelta = dictDelta;
- lowLimit = dictionary;
- } else {
- refDelta = 0;
- lowLimit = (const BYTE*)source;
- } }
- LZ4_putPosition(ip, cctx->hashTable, tableType, base);
- if ( ((dictIssue==dictSmall) ? (match>=lowRefLimit) : 1)
- && (match+MAX_DISTANCE>=ip)
- && (LZ4_read32(match+refDelta)==LZ4_read32(ip)) )
- { token=op++; *token=0; goto _next_match; }
+ if (tableType == byPtr) {
+ match = LZ4_getPosition(ip, cctx->hashTable, tableType, base);
+ LZ4_putPosition(ip, cctx->hashTable, tableType, base);
+ if ( (match+MAX_DISTANCE >= ip)
+ && (LZ4_read32(match) == LZ4_read32(ip)) )
+ { token=op++; *token=0; goto _next_match; }
+
+ } else { /* byU32, byU16 */
+
+ U32 const h = LZ4_hashPosition(ip, tableType);
+ U32 const current = (U32)(ip-base);
+ U32 matchIndex = LZ4_getIndexOnHash(h, cctx->hashTable, tableType);
+ assert(matchIndex < current);
+ if (dictDirective == usingDictCtx) {
+ if (matchIndex < startIndex) {
+ /* there was no match, try the dictionary */
+ matchIndex = LZ4_getIndexOnHash(h, dictCtx->hashTable, byU32);
+ match = dictBase + matchIndex;
+ lowLimit = dictionary; /* required for match length counter */
+ matchIndex += dictDelta;
+ } else {
+ match = base + matchIndex;
+ lowLimit = (const BYTE*)source; /* required for match length counter */
+ }
+ } else if (dictDirective==usingExtDict) {
+ if (matchIndex < startIndex) {
+ match = dictBase + matchIndex;
+ lowLimit = dictionary; /* required for match length counter */
+ } else {
+ match = base + matchIndex;
+ lowLimit = (const BYTE*)source; /* required for match length counter */
+ }
+ } else { /* single memory segment */
+ match = base + matchIndex;
+ }
+ LZ4_putIndexOnHash(current, h, cctx->hashTable, tableType);
+ assert(matchIndex < current);
+ if ( ((dictIssue==dictSmall) ? (matchIndex >= prefixIdxLimit) : 1)
+ && ((tableType==byU16) ? 1 : (matchIndex+MAX_DISTANCE >= current))
+ && (LZ4_read32(match) == LZ4_read32(ip)) ) {
+ token=op++;
+ *token=0;
+ if (maybe_extMem) offset = current - matchIndex;
+ DEBUGLOG(6, "seq.start:%i, literals=%u, match.start:%i",
+ (int)(anchor-(const BYTE*)source), 0, (int)(ip-(const BYTE*)source));
+ goto _next_match;
+ }
+ }
+
/* Prepare next loop */
forwardH = LZ4_hashPosition(++ip, tableType);
+
}
_last_literals:
/* Encode Last Literals */
- { size_t const lastRun = (size_t)(iend - anchor);
+ { size_t lastRun = (size_t)(iend - anchor);
if ( (outputLimited) && /* Check output buffer overflow */
- ((op - (BYTE*)dest) + lastRun + 1 + ((lastRun+255-RUN_MASK)/255) > (U32)maxOutputSize) )
- return 0;
+ (op + lastRun + 1 + ((lastRun+255-RUN_MASK)/255) > olimit)) {
+ if (outputLimited == fillOutput) {
+ /* adapt lastRun to fill 'dst' */
+ lastRun = (olimit-op) - 1;
+ lastRun -= (lastRun+240)/255;
+ }
+ if (outputLimited == limitedOutput)
+ return 0;
+ }
if (lastRun >= RUN_MASK) {
size_t accumulator = lastRun - RUN_MASK;
*op++ = RUN_MASK << ML_BITS;
@@ -666,11 +982,15 @@
*op++ = (BYTE)(lastRun<<ML_BITS);
}
memcpy(op, anchor, lastRun);
+ ip = anchor + lastRun;
op += lastRun;
}
- /* End */
- return (int) (((char*)op)-dest);
+ if (outputLimited == fillOutput) {
+ *inputConsumed = (int) (((const char*)ip)-source);
+ }
+ DEBUGLOG(5, "LZ4_compress_generic: compressed %i bytes into %i bytes", inputSize, (int)(((char*)op) - dest));
+ return (int)(((char*)op) - dest);
}
@@ -677,19 +997,67 @@
int LZ4_compress_fast_extState(void* state, const char* source, char* dest, int inputSize, int maxOutputSize, int acceleration)
{
LZ4_stream_t_internal* ctx = &((LZ4_stream_t*)state)->internal_donotuse;
+ if (acceleration < 1) acceleration = ACCELERATION_DEFAULT;
LZ4_resetStream((LZ4_stream_t*)state);
+ if (maxOutputSize >= LZ4_compressBound(inputSize)) {
+ if (inputSize < LZ4_64Klimit) {
+ return LZ4_compress_generic(ctx, source, dest, inputSize, NULL, 0, notLimited, byU16, noDict, noDictIssue, acceleration);
+ } else {
+ const tableType_t tableType = ((sizeof(void*)==4) && ((uptrval)source > MAX_DISTANCE)) ? byPtr : byU32;
+ return LZ4_compress_generic(ctx, source, dest, inputSize, NULL, 0, notLimited, tableType, noDict, noDictIssue, acceleration);
+ }
+ } else {
+ if (inputSize < LZ4_64Klimit) {;
+ return LZ4_compress_generic(ctx, source, dest, inputSize, NULL, maxOutputSize, limitedOutput, byU16, noDict, noDictIssue, acceleration);
+ } else {
+ const tableType_t tableType = ((sizeof(void*)==4) && ((uptrval)source > MAX_DISTANCE)) ? byPtr : byU32;
+ return LZ4_compress_generic(ctx, source, dest, inputSize, NULL, maxOutputSize, limitedOutput, tableType, noDict, noDictIssue, acceleration);
+ }
+ }
+}
+
+/**
+ * LZ4_compress_fast_extState_fastReset() :
+ * A variant of LZ4_compress_fast_extState().
+ *
+ * Using this variant avoids an expensive initialization step. It is only safe
+ * to call if the state buffer is known to be correctly initialized already
+ * (see comment in lz4.h on LZ4_resetStream_fast() for a definition of
+ * "correctly initialized").
+ */
+int LZ4_compress_fast_extState_fastReset(void* state, const char* src, char* dst, int srcSize, int dstCapacity, int acceleration)
+{
+ LZ4_stream_t_internal* ctx = &((LZ4_stream_t*)state)->internal_donotuse;
if (acceleration < 1) acceleration = ACCELERATION_DEFAULT;
- if (maxOutputSize >= LZ4_compressBound(inputSize)) {
- if (inputSize < LZ4_64Klimit)
- return LZ4_compress_generic(ctx, source, dest, inputSize, 0, notLimited, byU16, noDict, noDictIssue, acceleration);
- else
- return LZ4_compress_generic(ctx, source, dest, inputSize, 0, notLimited, (sizeof(void*)==8) ? byU32 : byPtr, noDict, noDictIssue, acceleration);
+ if (dstCapacity >= LZ4_compressBound(srcSize)) {
+ if (srcSize < LZ4_64Klimit) {
+ const tableType_t tableType = byU16;
+ LZ4_prepareTable(ctx, srcSize, tableType);
+ if (ctx->currentOffset) {
+ return LZ4_compress_generic(ctx, src, dst, srcSize, NULL, 0, notLimited, tableType, noDict, dictSmall, acceleration);
+ } else {
+ return LZ4_compress_generic(ctx, src, dst, srcSize, NULL, 0, notLimited, tableType, noDict, noDictIssue, acceleration);
+ }
+ } else {
+ const tableType_t tableType = ((sizeof(void*)==4) && ((uptrval)src > MAX_DISTANCE)) ? byPtr : byU32;
+ LZ4_prepareTable(ctx, srcSize, tableType);
+ return LZ4_compress_generic(ctx, src, dst, srcSize, NULL, 0, notLimited, tableType, noDict, noDictIssue, acceleration);
+ }
} else {
- if (inputSize < LZ4_64Klimit)
- return LZ4_compress_generic(ctx, source, dest, inputSize, maxOutputSize, limitedOutput, byU16, noDict, noDictIssue, acceleration);
- else
- return LZ4_compress_generic(ctx, source, dest, inputSize, maxOutputSize, limitedOutput, (sizeof(void*)==8) ? byU32 : byPtr, noDict, noDictIssue, acceleration);
+ if (srcSize < LZ4_64Klimit) {
+ const tableType_t tableType = byU16;
+ LZ4_prepareTable(ctx, srcSize, tableType);
+ if (ctx->currentOffset) {
+ return LZ4_compress_generic(ctx, src, dst, srcSize, NULL, dstCapacity, limitedOutput, tableType, noDict, dictSmall, acceleration);
+ } else {
+ return LZ4_compress_generic(ctx, src, dst, srcSize, NULL, dstCapacity, limitedOutput, tableType, noDict, noDictIssue, acceleration);
+ }
+ } else {
+ const tableType_t tableType = ((sizeof(void*)==4) && ((uptrval)src > MAX_DISTANCE)) ? byPtr : byU32;
+ LZ4_prepareTable(ctx, srcSize, tableType);
+ return LZ4_compress_generic(ctx, src, dst, srcSize, NULL, dstCapacity, limitedOutput, tableType, noDict, noDictIssue, acceleration);
+ }
}
}
@@ -696,15 +1064,16 @@
int LZ4_compress_fast(const char* source, char* dest, int inputSize, int maxOutputSize, int acceleration)
{
+ int result;
#if (LZ4_HEAPMODE)
- void* ctxPtr = ALLOCATOR(1, sizeof(LZ4_stream_t)); /* malloc-calloc always properly aligned */
+ LZ4_stream_t* ctxPtr = ALLOC(sizeof(LZ4_stream_t)); /* malloc-calloc always properly aligned */
+ if (ctxPtr == NULL) return 0;
#else
LZ4_stream_t ctx;
- void* const ctxPtr = &ctx;
+ LZ4_stream_t* const ctxPtr = &ctx;
#endif
+ result = LZ4_compress_fast_extState(ctxPtr, source, dest, inputSize, maxOutputSize, acceleration);
- int const result = LZ4_compress_fast_extState(ctxPtr, source, dest, inputSize, maxOutputSize, acceleration);
-
#if (LZ4_HEAPMODE)
FREEMEM(ctxPtr);
#endif
@@ -726,172 +1095,15 @@
LZ4_resetStream(&ctx);
if (inputSize < LZ4_64Klimit)
- return LZ4_compress_generic(&ctx.internal_donotuse, source, dest, inputSize, maxOutputSize, limitedOutput, byU16, noDict, noDictIssue, acceleration);
+ return LZ4_compress_generic(&ctx.internal_donotuse, source, dest, inputSize, NULL, maxOutputSize, limitedOutput, byU16, noDict, noDictIssue, acceleration);
else
- return LZ4_compress_generic(&ctx.internal_donotuse, source, dest, inputSize, maxOutputSize, limitedOutput, sizeof(void*)==8 ? byU32 : byPtr, noDict, noDictIssue, acceleration);
+ return LZ4_compress_generic(&ctx.internal_donotuse, source, dest, inputSize, NULL, maxOutputSize, limitedOutput, sizeof(void*)==8 ? byU32 : byPtr, noDict, noDictIssue, acceleration);
}
-/*-******************************
-* *_destSize() variant
-********************************/
-
-static int LZ4_compress_destSize_generic(
- LZ4_stream_t_internal* const ctx,
- const char* const src,
- char* const dst,
- int* const srcSizePtr,
- const int targetDstSize,
- const tableType_t tableType)
-{
- const BYTE* ip = (const BYTE*) src;
- const BYTE* base = (const BYTE*) src;
- const BYTE* lowLimit = (const BYTE*) src;
- const BYTE* anchor = ip;
- const BYTE* const iend = ip + *srcSizePtr;
- const BYTE* const mflimit = iend - MFLIMIT;
- const BYTE* const matchlimit = iend - LASTLITERALS;
-
- BYTE* op = (BYTE*) dst;
- BYTE* const oend = op + targetDstSize;
- BYTE* const oMaxLit = op + targetDstSize - 2 /* offset */ - 8 /* because 8+MINMATCH==MFLIMIT */ - 1 /* token */;
- BYTE* const oMaxMatch = op + targetDstSize - (LASTLITERALS + 1 /* token */);
- BYTE* const oMaxSeq = oMaxLit - 1 /* token */;
-
- U32 forwardH;
-
-
- /* Init conditions */
- if (targetDstSize < 1) return 0; /* Impossible to store anything */
- if ((U32)*srcSizePtr > (U32)LZ4_MAX_INPUT_SIZE) return 0; /* Unsupported input size, too large (or negative) */
- if ((tableType == byU16) && (*srcSizePtr>=LZ4_64Klimit)) return 0; /* Size too large (not within 64K limit) */
- if (*srcSizePtr<LZ4_minLength) goto _last_literals; /* Input too small, no compression (all literals) */
-
- /* First Byte */
- *srcSizePtr = 0;
- LZ4_putPosition(ip, ctx->hashTable, tableType, base);
- ip++; forwardH = LZ4_hashPosition(ip, tableType);
-
- /* Main Loop */
- for ( ; ; ) {
- const BYTE* match;
- BYTE* token;
-
- /* Find a match */
- { const BYTE* forwardIp = ip;
- unsigned step = 1;
- unsigned searchMatchNb = 1 << LZ4_skipTrigger;
-
- do {
- U32 h = forwardH;
- ip = forwardIp;
- forwardIp += step;
- step = (searchMatchNb++ >> LZ4_skipTrigger);
-
- if (unlikely(forwardIp > mflimit)) goto _last_literals;
-
- match = LZ4_getPositionOnHash(h, ctx->hashTable, tableType, base);
- forwardH = LZ4_hashPosition(forwardIp, tableType);
- LZ4_putPositionOnHash(ip, h, ctx->hashTable, tableType, base);
-
- } while ( ((tableType==byU16) ? 0 : (match + MAX_DISTANCE < ip))
- || (LZ4_read32(match) != LZ4_read32(ip)) );
- }
-
- /* Catch up */
- while ((ip>anchor) && (match > lowLimit) && (unlikely(ip[-1]==match[-1]))) { ip--; match--; }
-
- /* Encode Literal length */
- { unsigned litLength = (unsigned)(ip - anchor);
- token = op++;
- if (op + ((litLength+240)/255) + litLength > oMaxLit) {
- /* Not enough space for a last match */
- op--;
- goto _last_literals;
- }
- if (litLength>=RUN_MASK) {
- unsigned len = litLength - RUN_MASK;
- *token=(RUN_MASK<<ML_BITS);
- for(; len >= 255 ; len-=255) *op++ = 255;
- *op++ = (BYTE)len;
- }
- else *token = (BYTE)(litLength<<ML_BITS);
-
- /* Copy Literals */
- LZ4_wildCopy(op, anchor, op+litLength);
- op += litLength;
- }
-
-_next_match:
- /* Encode Offset */
- LZ4_writeLE16(op, (U16)(ip-match)); op+=2;
-
- /* Encode MatchLength */
- { size_t matchLength = LZ4_count(ip+MINMATCH, match+MINMATCH, matchlimit);
-
- if (op + ((matchLength+240)/255) > oMaxMatch) {
- /* Match description too long : reduce it */
- matchLength = (15-1) + (oMaxMatch-op) * 255;
- }
- ip += MINMATCH + matchLength;
-
- if (matchLength>=ML_MASK) {
- *token += ML_MASK;
- matchLength -= ML_MASK;
- while (matchLength >= 255) { matchLength-=255; *op++ = 255; }
- *op++ = (BYTE)matchLength;
- }
- else *token += (BYTE)(matchLength);
- }
-
- anchor = ip;
-
- /* Test end of block */
- if (ip > mflimit) break;
- if (op > oMaxSeq) break;
-
- /* Fill table */
- LZ4_putPosition(ip-2, ctx->hashTable, tableType, base);
-
- /* Test next position */
- match = LZ4_getPosition(ip, ctx->hashTable, tableType, base);
- LZ4_putPosition(ip, ctx->hashTable, tableType, base);
- if ( (match+MAX_DISTANCE>=ip)
- && (LZ4_read32(match)==LZ4_read32(ip)) )
- { token=op++; *token=0; goto _next_match; }
-
- /* Prepare next loop */
- forwardH = LZ4_hashPosition(++ip, tableType);
- }
-
-_last_literals:
- /* Encode Last Literals */
- { size_t lastRunSize = (size_t)(iend - anchor);
- if (op + 1 /* token */ + ((lastRunSize+240)/255) /* litLength */ + lastRunSize /* literals */ > oend) {
- /* adapt lastRunSize to fill 'dst' */
- lastRunSize = (oend-op) - 1;
- lastRunSize -= (lastRunSize+240)/255;
- }
- ip = anchor + lastRunSize;
-
- if (lastRunSize >= RUN_MASK) {
- size_t accumulator = lastRunSize - RUN_MASK;
- *op++ = RUN_MASK << ML_BITS;
- for(; accumulator >= 255 ; accumulator-=255) *op++ = 255;
- *op++ = (BYTE) accumulator;
- } else {
- *op++ = (BYTE)(lastRunSize<<ML_BITS);
- }
- memcpy(op, anchor, lastRunSize);
- op += lastRunSize;
- }
-
- /* End */
- *srcSizePtr = (int) (((const char*)ip)-src);
- return (int) (((char*)op)-dst);
-}
-
-
+/* Note!: This function leaves the stream in an unclean/broken state!
+ * It is not safe to subsequently use the same state with a _fastReset() or
+ * _continue() call without resetting it. */
static int LZ4_compress_destSize_extState (LZ4_stream_t* state, const char* src, char* dst, int* srcSizePtr, int targetDstSize)
{
LZ4_resetStream(state);
@@ -899,11 +1111,12 @@
if (targetDstSize >= LZ4_compressBound(*srcSizePtr)) { /* compression success is guaranteed */
return LZ4_compress_fast_extState(state, src, dst, *srcSizePtr, targetDstSize, 1);
} else {
- if (*srcSizePtr < LZ4_64Klimit)
- return LZ4_compress_destSize_generic(&state->internal_donotuse, src, dst, srcSizePtr, targetDstSize, byU16);
- else
- return LZ4_compress_destSize_generic(&state->internal_donotuse, src, dst, srcSizePtr, targetDstSize, sizeof(void*)==8 ? byU32 : byPtr);
- }
+ if (*srcSizePtr < LZ4_64Klimit) {
+ return LZ4_compress_generic(&state->internal_donotuse, src, dst, *srcSizePtr, srcSizePtr, targetDstSize, fillOutput, byU16, noDict, noDictIssue, 1);
+ } else {
+ tableType_t const tableType = ((sizeof(void*)==4) && ((uptrval)src > MAX_DISTANCE)) ? byPtr : byU32;
+ return LZ4_compress_generic(&state->internal_donotuse, src, dst, *srcSizePtr, srcSizePtr, targetDstSize, fillOutput, tableType, noDict, noDictIssue, 1);
+ } }
}
@@ -910,7 +1123,8 @@
int LZ4_compress_destSize(const char* src, char* dst, int* srcSizePtr, int targetDstSize)
{
#if (LZ4_HEAPMODE)
- LZ4_stream_t* ctx = (LZ4_stream_t*)ALLOCATOR(1, sizeof(LZ4_stream_t)); /* malloc-calloc always properly aligned */
+ LZ4_stream_t* ctx = (LZ4_stream_t*)ALLOC(sizeof(LZ4_stream_t)); /* malloc-calloc always properly aligned */
+ if (ctx == NULL) return 0;
#else
LZ4_stream_t ctxBody;
LZ4_stream_t* ctx = &ctxBody;
@@ -932,8 +1146,10 @@
LZ4_stream_t* LZ4_createStream(void)
{
- LZ4_stream_t* lz4s = (LZ4_stream_t*)ALLOCATOR(8, LZ4_STREAMSIZE_U64);
+ LZ4_stream_t* lz4s = (LZ4_stream_t*)ALLOC(sizeof(LZ4_stream_t));
LZ4_STATIC_ASSERT(LZ4_STREAMSIZE >= sizeof(LZ4_stream_t_internal)); /* A compilation error here means LZ4_STREAMSIZE is not large enough */
+ DEBUGLOG(4, "LZ4_createStream %p", lz4s);
+ if (lz4s == NULL) return NULL;
LZ4_resetStream(lz4s);
return lz4s;
}
@@ -940,12 +1156,18 @@
void LZ4_resetStream (LZ4_stream_t* LZ4_stream)
{
+ DEBUGLOG(5, "LZ4_resetStream (ctx:%p)", LZ4_stream);
MEM_INIT(LZ4_stream, 0, sizeof(LZ4_stream_t));
}
+void LZ4_resetStream_fast(LZ4_stream_t* ctx) {
+ LZ4_prepareTable(&(ctx->internal_donotuse), 0, byU32);
+}
+
int LZ4_freeStream (LZ4_stream_t* LZ4_stream)
{
if (!LZ4_stream) return 0; /* support free on NULL */
+ DEBUGLOG(5, "LZ4_freeStream %p", LZ4_stream);
FREEMEM(LZ4_stream);
return (0);
}
@@ -955,28 +1177,39 @@
int LZ4_loadDict (LZ4_stream_t* LZ4_dict, const char* dictionary, int dictSize)
{
LZ4_stream_t_internal* dict = &LZ4_dict->internal_donotuse;
+ const tableType_t tableType = byU32;
const BYTE* p = (const BYTE*)dictionary;
const BYTE* const dictEnd = p + dictSize;
const BYTE* base;
- if ((dict->initCheck) || (dict->currentOffset > 1 GB)) /* Uninitialized structure, or reuse overflow */
- LZ4_resetStream(LZ4_dict);
+ DEBUGLOG(4, "LZ4_loadDict (%i bytes from %p into %p)", dictSize, dictionary, LZ4_dict);
- if (dictSize < (int)HASH_UNIT) {
- dict->dictionary = NULL;
- dict->dictSize = 0;
- return 0;
- }
+ /* It's necessary to reset the context,
+ * and not just continue it with prepareTable()
+ * to avoid any risk of generating overflowing matchIndex
+ * when compressing using this dictionary */
+ LZ4_resetStream(LZ4_dict);
+ /* We always increment the offset by 64 KB, since, if the dict is longer,
+ * we truncate it to the last 64k, and if it's shorter, we still want to
+ * advance by a whole window length so we can provide the guarantee that
+ * there are only valid offsets in the window, which allows an optimization
+ * in LZ4_compress_fast_continue() where it uses noDictIssue even when the
+ * dictionary isn't a full 64k. */
+
if ((dictEnd - p) > 64 KB) p = dictEnd - 64 KB;
- dict->currentOffset += 64 KB;
- base = p - dict->currentOffset;
+ base = dictEnd - 64 KB - dict->currentOffset;
dict->dictionary = p;
dict->dictSize = (U32)(dictEnd - p);
- dict->currentOffset += dict->dictSize;
+ dict->currentOffset += 64 KB;
+ dict->tableType = tableType;
+ if (dictSize < (int)HASH_UNIT) {
+ return 0;
+ }
+
while (p <= dictEnd-HASH_UNIT) {
- LZ4_putPosition(p, dict->hashTable, byU32, base);
+ LZ4_putPosition(p, dict->hashTable, tableType, base);
p+=3;
}
@@ -983,15 +1216,31 @@
return dict->dictSize;
}
+void LZ4_attach_dictionary(LZ4_stream_t *working_stream, const LZ4_stream_t *dictionary_stream) {
+ if (dictionary_stream != NULL) {
+ /* If the current offset is zero, we will never look in the
+ * external dictionary context, since there is no value a table
+ * entry can take that indicate a miss. In that case, we need
+ * to bump the offset to something non-zero.
+ */
+ if (working_stream->internal_donotuse.currentOffset == 0) {
+ working_stream->internal_donotuse.currentOffset = 64 KB;
+ }
+ working_stream->internal_donotuse.dictCtx = &(dictionary_stream->internal_donotuse);
+ } else {
+ working_stream->internal_donotuse.dictCtx = NULL;
+ }
+}
-static void LZ4_renormDictT(LZ4_stream_t_internal* LZ4_dict, const BYTE* src)
+
+static void LZ4_renormDictT(LZ4_stream_t_internal* LZ4_dict, int nextSize)
{
- if ((LZ4_dict->currentOffset > 0x80000000) ||
- ((uptrval)LZ4_dict->currentOffset > (uptrval)src)) { /* address space overflow */
+ if (LZ4_dict->currentOffset + nextSize > 0x80000000) { /* potential ptrdiff_t overflow (32-bits mode) */
/* rescale hash table */
U32 const delta = LZ4_dict->currentOffset - 64 KB;
const BYTE* dictEnd = LZ4_dict->dictionary + LZ4_dict->dictSize;
int i;
+ DEBUGLOG(4, "LZ4_renormDictT");
for (i=0; i<LZ4_HASH_SIZE_U32; i++) {
if (LZ4_dict->hashTable[i] < delta) LZ4_dict->hashTable[i]=0;
else LZ4_dict->hashTable[i] -= delta;
@@ -1005,15 +1254,25 @@
int LZ4_compress_fast_continue (LZ4_stream_t* LZ4_stream, const char* source, char* dest, int inputSize, int maxOutputSize, int acceleration)
{
+ const tableType_t tableType = byU32;
LZ4_stream_t_internal* streamPtr = &LZ4_stream->internal_donotuse;
- const BYTE* const dictEnd = streamPtr->dictionary + streamPtr->dictSize;
+ const BYTE* dictEnd = streamPtr->dictionary + streamPtr->dictSize;
- const BYTE* smallest = (const BYTE*) source;
+ DEBUGLOG(5, "LZ4_compress_fast_continue (inputSize=%i)", inputSize);
+
if (streamPtr->initCheck) return 0; /* Uninitialized structure detected */
- if ((streamPtr->dictSize>0) && (smallest>dictEnd)) smallest = dictEnd;
- LZ4_renormDictT(streamPtr, smallest);
+ LZ4_renormDictT(streamPtr, inputSize); /* avoid index overflow */
if (acceleration < 1) acceleration = ACCELERATION_DEFAULT;
+ /* invalidate tiny dictionaries */
+ if ( (streamPtr->dictSize-1 < 4) /* intentional underflow */
+ && (dictEnd != (const BYTE*)source) ) {
+ DEBUGLOG(5, "LZ4_compress_fast_continue: dictSize(%u) at addr:%p is too small", streamPtr->dictSize, streamPtr->dictionary);
+ streamPtr->dictSize = 0;
+ streamPtr->dictionary = (const BYTE*)source;
+ dictEnd = (const BYTE*)source;
+ }
+
/* Check overlapping input/dictionary space */
{ const BYTE* sourceEnd = (const BYTE*) source + inputSize;
if ((sourceEnd > streamPtr->dictionary) && (sourceEnd < dictEnd)) {
@@ -1026,46 +1285,61 @@
/* prefix mode : source data follows dictionary */
if (dictEnd == (const BYTE*)source) {
- int result;
if ((streamPtr->dictSize < 64 KB) && (streamPtr->dictSize < streamPtr->currentOffset))
- result = LZ4_compress_generic(streamPtr, source, dest, inputSize, maxOutputSize, limitedOutput, byU32, withPrefix64k, dictSmall, acceleration);
+ return LZ4_compress_generic(streamPtr, source, dest, inputSize, NULL, maxOutputSize, limitedOutput, tableType, withPrefix64k, dictSmall, acceleration);
else
- result = LZ4_compress_generic(streamPtr, source, dest, inputSize, maxOutputSize, limitedOutput, byU32, withPrefix64k, noDictIssue, acceleration);
- streamPtr->dictSize += (U32)inputSize;
- streamPtr->currentOffset += (U32)inputSize;
- return result;
+ return LZ4_compress_generic(streamPtr, source, dest, inputSize, NULL, maxOutputSize, limitedOutput, tableType, withPrefix64k, noDictIssue, acceleration);
}
/* external dictionary mode */
{ int result;
- if ((streamPtr->dictSize < 64 KB) && (streamPtr->dictSize < streamPtr->currentOffset))
- result = LZ4_compress_generic(streamPtr, source, dest, inputSize, maxOutputSize, limitedOutput, byU32, usingExtDict, dictSmall, acceleration);
- else
- result = LZ4_compress_generic(streamPtr, source, dest, inputSize, maxOutputSize, limitedOutput, byU32, usingExtDict, noDictIssue, acceleration);
+ if (streamPtr->dictCtx) {
+ /* We depend here on the fact that dictCtx'es (produced by
+ * LZ4_loadDict) guarantee that their tables contain no references
+ * to offsets between dictCtx->currentOffset - 64 KB and
+ * dictCtx->currentOffset - dictCtx->dictSize. This makes it safe
+ * to use noDictIssue even when the dict isn't a full 64 KB.
+ */
+ if (inputSize > 4 KB) {
+ /* For compressing large blobs, it is faster to pay the setup
+ * cost to copy the dictionary's tables into the active context,
+ * so that the compression loop is only looking into one table.
+ */
+ memcpy(streamPtr, streamPtr->dictCtx, sizeof(LZ4_stream_t));
+ result = LZ4_compress_generic(streamPtr, source, dest, inputSize, NULL, maxOutputSize, limitedOutput, tableType, usingExtDict, noDictIssue, acceleration);
+ } else {
+ result = LZ4_compress_generic(streamPtr, source, dest, inputSize, NULL, maxOutputSize, limitedOutput, tableType, usingDictCtx, noDictIssue, acceleration);
+ }
+ } else {
+ if ((streamPtr->dictSize < 64 KB) && (streamPtr->dictSize < streamPtr->currentOffset)) {
+ result = LZ4_compress_generic(streamPtr, source, dest, inputSize, NULL, maxOutputSize, limitedOutput, tableType, usingExtDict, dictSmall, acceleration);
+ } else {
+ result = LZ4_compress_generic(streamPtr, source, dest, inputSize, NULL, maxOutputSize, limitedOutput, tableType, usingExtDict, noDictIssue, acceleration);
+ }
+ }
streamPtr->dictionary = (const BYTE*)source;
streamPtr->dictSize = (U32)inputSize;
- streamPtr->currentOffset += (U32)inputSize;
return result;
}
}
-/* Hidden debug function, to force external dictionary mode */
-int LZ4_compress_forceExtDict (LZ4_stream_t* LZ4_dict, const char* source, char* dest, int inputSize)
+/* Hidden debug function, to force-test external dictionary mode */
+int LZ4_compress_forceExtDict (LZ4_stream_t* LZ4_dict, const char* source, char* dest, int srcSize)
{
LZ4_stream_t_internal* streamPtr = &LZ4_dict->internal_donotuse;
int result;
- const BYTE* const dictEnd = streamPtr->dictionary + streamPtr->dictSize;
- const BYTE* smallest = dictEnd;
- if (smallest > (const BYTE*) source) smallest = (const BYTE*) source;
- LZ4_renormDictT(streamPtr, smallest);
+ LZ4_renormDictT(streamPtr, srcSize);
- result = LZ4_compress_generic(streamPtr, source, dest, inputSize, 0, notLimited, byU32, usingExtDict, noDictIssue, 1);
+ if ((streamPtr->dictSize < 64 KB) && (streamPtr->dictSize < streamPtr->currentOffset)) {
+ result = LZ4_compress_generic(streamPtr, source, dest, srcSize, NULL, 0, notLimited, byU32, usingExtDict, dictSmall, 1);
+ } else {
+ result = LZ4_compress_generic(streamPtr, source, dest, srcSize, NULL, 0, notLimited, byU32, usingExtDict, noDictIssue, 1);
+ }
streamPtr->dictionary = (const BYTE*)source;
- streamPtr->dictSize = (U32)inputSize;
- streamPtr->currentOffset += (U32)inputSize;
+ streamPtr->dictSize = (U32)srcSize;
return result;
}
@@ -1100,59 +1374,108 @@
* 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,
+ * 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.
*/
-FORCE_INLINE int LZ4_decompress_generic(
- const char* const source,
- char* const dest,
- int inputSize,
- int outputSize, /* If endOnInput==endOnInputSize, this value is the max size of Output Buffer. */
+LZ4_FORCE_O2_GCC_PPC64LE
+LZ4_FORCE_INLINE int LZ4_decompress_generic(
+ const char* const src,
+ char* const dst,
+ int srcSize,
+ int outputSize, /* If endOnInput==endOnInputSize, this value is `dstCapacity` */
int endOnInput, /* endOnOutputSize, endOnInputSize */
int partialDecoding, /* full, partial */
int targetOutputSize, /* only used if partialDecoding==partial */
int dict, /* noDict, withPrefix64k, usingExtDict */
- const BYTE* const lowPrefix, /* == dest when no prefix */
+ const BYTE* const lowPrefix, /* always <= dst, == dst when no prefix */
const BYTE* const dictStart, /* only if dict==usingExtDict */
const size_t dictSize /* note : = 0 if noDict */
)
{
- /* Local Variables */
- const BYTE* ip = (const BYTE*) source;
- const BYTE* const iend = ip + inputSize;
+ const BYTE* ip = (const BYTE*) src;
+ const BYTE* const iend = ip + srcSize;
- BYTE* op = (BYTE*) dest;
+ BYTE* op = (BYTE*) dst;
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;
- const unsigned dec32table[] = {0, 1, 2, 1, 4, 4, 4, 4};
- const int dec64table[] = {0, 0, 0, -1, 0, 1, 2, 3};
+ const unsigned inc32table[8] = {0, 1, 2, 1, 0, 4, 4, 4};
+ 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, "LZ4_decompress_generic (srcSize:%i)", srcSize);
+
/* Special cases */
- if ((partialDecoding) && (oexit > oend-MFLIMIT)) oexit = oend-MFLIMIT; /* targetOutputSize too high => decode everything */
- if ((endOnInput) && (unlikely(outputSize==0))) return ((inputSize==1) && (*ip==0)) ? 0 : -1; /* Empty output buffer */
+ if ((partialDecoding) && (oexit > oend-MFLIMIT)) oexit = oend-MFLIMIT; /* targetOutputSize too high => just decode everything */
+ if ((endOnInput) && (unlikely(outputSize==0))) return ((srcSize==1) && (*ip==0)) ? 0 : -1; /* Empty output buffer */
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 const token = *ip++;
- if ((length=(token>>ML_BITS)) == RUN_MASK) {
+ size_t length = token >> ML_BITS; /* literal length */
+
+ assert(!endOnInput || ip <= iend); /* ip < iend before the increment */
+
+ /* 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).
+ */
+ 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 */
+ 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;
+
+ /* Do not deal with overlapping matches. */
+ if ( (length != ML_MASK)
+ && (offset >= 8)
+ && (dict==withPrefix64k || match >= lowPrefix) ) {
+ /* Copy the match. */
+ memcpy(op + 0, match + 0, 8);
+ memcpy(op + 8, match + 8, 8);
+ 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 s;
+ if (unlikely(endOnInput ? ip >= iend-RUN_MASK : 0)) goto _output_error; /* overflow detection */
do {
s = *ip++;
length += s;
@@ -1184,11 +1507,14 @@
/* get offset */
offset = LZ4_readLE16(ip); ip+=2;
match = op - offset;
- if ((checkOffset) && (unlikely(match < lowLimit))) goto _output_error; /* Error : offset outside buffers */
- LZ4_write32(op, (U32)offset); /* costs ~1%; silence an msan warning when offset==0 */
/* get matchlength */
length = token & ML_MASK;
+
+_copy_match:
+ if ((checkOffset) && (unlikely(match + dictSize < lowPrefix))) goto _output_error; /* Error : offset outside buffers */
+ LZ4_write32(op, (U32)offset); /* costs ~1%; silence an msan warning when offset==0 */
+
if (length == ML_MASK) {
unsigned s;
do {
@@ -1228,15 +1554,14 @@
/* 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];
+ match += inc32table[offset];
memcpy(op+4, match, 4);
- match -= dec64;
- } else { LZ4_copy8(op, match); match+=8; }
+ match -= dec64table[offset];
+ } else { memcpy(op, match, 8); match+=8; }
op += 8;
if (unlikely(cpy>oend-12)) {
@@ -1249,45 +1574,123 @@
}
while (op<cpy) *op++ = *match++;
} else {
- LZ4_copy8(op, match);
+ memcpy(op, match, 8);
if (length>16) LZ4_wildCopy(op+8, match+8, cpy);
}
- op=cpy; /* correction */
+ op = cpy; /* correction */
}
/* end of decoding */
if (endOnInput)
- return (int) (((char*)op)-dest); /* Nb of output bytes decoded */
+ return (int) (((char*)op)-dst); /* Nb of output bytes decoded */
else
- return (int) (((const char*)ip)-source); /* Nb of input bytes read */
+ return (int) (((const char*)ip)-src); /* Nb of input bytes read */
/* Overflow error detected */
_output_error:
- return (int) (-(((const char*)ip)-source))-1;
+ return (int) (-(((const char*)ip)-src))-1;
}
+/*===== Instantiate the API decoding functions. =====*/
+
+LZ4_FORCE_O2_GCC_PPC64LE
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);
+ return LZ4_decompress_generic(source, dest, compressedSize, maxDecompressedSize,
+ endOnInputSize, full, 0, noDict,
+ (BYTE*)dest, NULL, 0);
}
+LZ4_FORCE_O2_GCC_PPC64LE
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);
+ return LZ4_decompress_generic(source, dest, compressedSize, maxDecompressedSize,
+ endOnInputSize, partial, targetOutputSize,
+ noDict, (BYTE*)dest, NULL, 0);
}
+LZ4_FORCE_O2_GCC_PPC64LE
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);
+ return LZ4_decompress_generic(source, dest, 0, originalSize,
+ endOnOutputSize, full, 0, withPrefix64k,
+ (BYTE*)dest - 64 KB, NULL, 0);
}
+/*===== Instantiate a few more decoding cases, used more than once. =====*/
+LZ4_FORCE_O2_GCC_PPC64LE /* Exported, an obsolete API function. */
+int LZ4_decompress_safe_withPrefix64k(const char* source, char* dest, int compressedSize, int maxOutputSize)
+{
+ return LZ4_decompress_generic(source, dest, compressedSize, maxOutputSize,
+ endOnInputSize, full, 0, withPrefix64k,
+ (BYTE*)dest - 64 KB, NULL, 0);
+}
+
+/* Another obsolete API function, paired with the previous one. */
+int LZ4_decompress_fast_withPrefix64k(const char* source, char* dest, int originalSize)
+{
+ /* LZ4_decompress_fast doesn't validate match offsets,
+ * and thus serves well with any prefixed dictionary. */
+ return LZ4_decompress_fast(source, dest, originalSize);
+}
+
+LZ4_FORCE_O2_GCC_PPC64LE
+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, full, 0, noDict,
+ (BYTE*)dest-prefixSize, NULL, 0);
+}
+
+LZ4_FORCE_O2_GCC_PPC64LE /* Exported under another name, for tests/fullbench.c */
+#define LZ4_decompress_safe_extDict LZ4_decompress_safe_forceExtDict
+int LZ4_decompress_safe_extDict(const char* source, char* dest, int compressedSize, int maxOutputSize,
+ const void* dictStart, size_t dictSize)
+{
+ return LZ4_decompress_generic(source, dest, compressedSize, maxOutputSize,
+ endOnInputSize, full, 0, usingExtDict,
+ (BYTE*)dest, (const BYTE*)dictStart, dictSize);
+}
+
+LZ4_FORCE_O2_GCC_PPC64LE
+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, full, 0, 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().
+ */
+LZ4_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, full, 0, usingExtDict,
+ (BYTE*)dest-prefixSize, (const BYTE*)dictStart, dictSize);
+}
+
+LZ4_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, full, 0, usingExtDict,
+ (BYTE*)dest-prefixSize, (const BYTE*)dictStart, dictSize);
+}
+
/*===== streaming decompression functions =====*/
LZ4_streamDecode_t* LZ4_createStreamDecode(void)
{
- LZ4_streamDecode_t* lz4s = (LZ4_streamDecode_t*) ALLOCATOR(1, sizeof(LZ4_streamDecode_t));
+ LZ4_streamDecode_t* lz4s = (LZ4_streamDecode_t*) ALLOC_AND_ZERO(sizeof(LZ4_streamDecode_t));
return lz4s;
}
@@ -1298,12 +1701,11 @@
return 0;
}
-/*!
- * LZ4_setStreamDecode() :
- * Use this function to instruct where to find the dictionary.
- * This function is not necessary if previous data is still available where it was decoded.
- * Loading a size of 0 is allowed (same effect as no dictionary).
- * Return : 1 if OK, 0 if error
+/*! LZ4_setStreamDecode() :
+ * Use this function to instruct where to find the dictionary.
+ * This function is not necessary if previous data is still available where it was decoded.
+ * Loading a size of 0 is allowed (same effect as no dictionary).
+ * @return : 1 if OK, 0 if error
*/
int LZ4_setStreamDecode (LZ4_streamDecode_t* LZ4_streamDecode, const char* dictionary, int dictSize)
{
@@ -1315,6 +1717,25 @@
return 1;
}
+/*! LZ4_decoderRingBufferSize() :
+ * when setting a ring buffer for streaming decompression (optional scenario),
+ * provides the minimum size of this ring buffer
+ * to be compatible with any source respecting maxBlockSize condition.
+ * Note : in a ring buffer scenario,
+ * blocks are presumed decompressed next to each other.
+ * When not enough space remains for next block (remainingSize < maxBlockSize),
+ * decoding resumes from beginning of ring buffer.
+ * @return : minimum ring buffer size,
+ * or 0 if there is an error (invalid maxBlockSize).
+ */
+int LZ4_decoderRingBufferSize(int maxBlockSize)
+{
+ if (maxBlockSize < 0) return 0;
+ if (maxBlockSize > LZ4_MAX_INPUT_SIZE) return 0;
+ if (maxBlockSize < 16) maxBlockSize = 16;
+ return LZ4_DECODER_RING_BUFFER_SIZE(maxBlockSize);
+}
+
/*
*_continue() :
These decoding functions allow decompression of multiple blocks in "streaming" mode.
@@ -1322,24 +1743,38 @@
If it's not possible, save the relevant part of decoded data into a safe buffer,
and indicate where it stands using LZ4_setStreamDecode()
*/
+LZ4_FORCE_O2_GCC_PPC64LE
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 (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_generic(source, dest, compressedSize, maxOutputSize,
- endOnInputSize, full, 0,
- usingExtDict, (BYTE*)dest, lz4sd->externalDict, lz4sd->extDictSize);
+ result = LZ4_decompress_safe_extDict(source, dest, compressedSize, maxOutputSize,
+ lz4sd->externalDict, lz4sd->extDictSize);
if (result <= 0) return result;
lz4sd->prefixSize = result;
lz4sd->prefixEnd = (BYTE*)dest + result;
@@ -1348,24 +1783,32 @@
return result;
}
+LZ4_FORCE_O2_GCC_PPC64LE
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 (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_generic(source, dest, 0, originalSize,
- endOnOutputSize, full, 0,
- usingExtDict, (BYTE*)dest, lz4sd->externalDict, 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;
@@ -1382,97 +1825,91 @@
the dictionary must be explicitly provided within parameters
*/
-FORCE_INLINE int LZ4_decompress_usingDict_generic(const char* source, char* dest, int compressedSize, int maxOutputSize, int safe, const char* dictStart, int dictSize)
+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_generic(source, dest, compressedSize, maxOutputSize, safe, full, 0, noDict, (BYTE*)dest, NULL, 0);
+ return LZ4_decompress_safe(source, dest, compressedSize, maxOutputSize);
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);
+ 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_generic(source, dest, compressedSize, maxOutputSize, safe, full, 0, usingExtDict, (BYTE*)dest, (const BYTE*)dictStart, dictSize);
+ return LZ4_decompress_safe_extDict(source, dest, compressedSize, maxOutputSize, 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);
+ if (dictSize==0 || dictStart+dictSize == dest)
+ return LZ4_decompress_fast(source, dest, originalSize);
+ return LZ4_decompress_fast_extDict(source, dest, originalSize, dictStart, dictSize);
}
-/* debug function */
-int LZ4_decompress_safe_forceExtDict(const char* source, char* dest, int compressedSize, int maxOutputSize, const char* dictStart, int dictSize)
-{
- return LZ4_decompress_generic(source, dest, compressedSize, maxOutputSize, endOnInputSize, full, 0, usingExtDict, (BYTE*)dest, (const BYTE*)dictStart, dictSize);
-}
-
/*=*************************************************
* Obsolete Functions
***************************************************/
/* obsolete compression functions */
-int LZ4_compress_limitedOutput(const char* source, char* dest, int inputSize, int maxOutputSize) { return LZ4_compress_default(source, dest, inputSize, maxOutputSize); }
-int LZ4_compress(const char* source, char* dest, int inputSize) { return LZ4_compress_default(source, dest, inputSize, LZ4_compressBound(inputSize)); }
-int LZ4_compress_limitedOutput_withState (void* state, const char* src, char* dst, int srcSize, int dstSize) { return LZ4_compress_fast_extState(state, src, dst, srcSize, dstSize, 1); }
-int LZ4_compress_withState (void* state, const char* src, char* dst, int srcSize) { return LZ4_compress_fast_extState(state, src, dst, srcSize, LZ4_compressBound(srcSize), 1); }
-int LZ4_compress_limitedOutput_continue (LZ4_stream_t* LZ4_stream, const char* src, char* dst, int srcSize, int maxDstSize) { return LZ4_compress_fast_continue(LZ4_stream, src, dst, srcSize, maxDstSize, 1); }
-int LZ4_compress_continue (LZ4_stream_t* LZ4_stream, const char* source, char* dest, int inputSize) { return LZ4_compress_fast_continue(LZ4_stream, source, dest, inputSize, LZ4_compressBound(inputSize), 1); }
+int LZ4_compress_limitedOutput(const char* source, char* dest, int inputSize, int maxOutputSize)
+{
+ return LZ4_compress_default(source, dest, inputSize, maxOutputSize);
+}
+int LZ4_compress(const char* source, char* dest, int inputSize)
+{
+ return LZ4_compress_default(source, dest, inputSize, LZ4_compressBound(inputSize));
+}
+int LZ4_compress_limitedOutput_withState (void* state, const char* src, char* dst, int srcSize, int dstSize)
+{
+ return LZ4_compress_fast_extState(state, src, dst, srcSize, dstSize, 1);
+}
+int LZ4_compress_withState (void* state, const char* src, char* dst, int srcSize)
+{
+ return LZ4_compress_fast_extState(state, src, dst, srcSize, LZ4_compressBound(srcSize), 1);
+}
+int LZ4_compress_limitedOutput_continue (LZ4_stream_t* LZ4_stream, const char* src, char* dst, int srcSize, int dstCapacity)
+{
+ return LZ4_compress_fast_continue(LZ4_stream, src, dst, srcSize, dstCapacity, 1);
+}
+int LZ4_compress_continue (LZ4_stream_t* LZ4_stream, const char* source, char* dest, int inputSize)
+{
+ return LZ4_compress_fast_continue(LZ4_stream, source, dest, inputSize, LZ4_compressBound(inputSize), 1);
+}
/*
-These function names are deprecated and should no longer be used.
+These decompression functions are deprecated and should no longer be used.
They are only provided here for compatibility with older user programs.
- LZ4_uncompress is totally equivalent to LZ4_decompress_fast
- LZ4_uncompress_unknownOutputSize is totally equivalent to LZ4_decompress_safe
*/
-int LZ4_uncompress (const char* source, char* dest, int outputSize) { return LZ4_decompress_fast(source, dest, outputSize); }
-int LZ4_uncompress_unknownOutputSize (const char* source, char* dest, int isize, int maxOutputSize) { return LZ4_decompress_safe(source, dest, isize, maxOutputSize); }
+int LZ4_uncompress (const char* source, char* dest, int outputSize)
+{
+ return LZ4_decompress_fast(source, dest, outputSize);
+}
+int LZ4_uncompress_unknownOutputSize (const char* source, char* dest, int isize, int maxOutputSize)
+{
+ return LZ4_decompress_safe(source, dest, isize, maxOutputSize);
+}
-
/* Obsolete Streaming functions */
int LZ4_sizeofStreamState() { return LZ4_STREAMSIZE; }
-static void LZ4_init(LZ4_stream_t* lz4ds, BYTE* base)
-{
- MEM_INIT(lz4ds, 0, sizeof(LZ4_stream_t));
- lz4ds->internal_donotuse.bufferStart = base;
-}
-
int LZ4_resetStreamState(void* state, char* inputBuffer)
{
- if ((((uptrval)state) & 3) != 0) return 1; /* Error : pointer is not aligned on 4-bytes boundary */
- LZ4_init((LZ4_stream_t*)state, (BYTE*)inputBuffer);
+ (void)inputBuffer;
+ LZ4_resetStream((LZ4_stream_t*)state);
return 0;
}
void* LZ4_create (char* inputBuffer)
{
- LZ4_stream_t* lz4ds = (LZ4_stream_t*)ALLOCATOR(8, sizeof(LZ4_stream_t));
- LZ4_init (lz4ds, (BYTE*)inputBuffer);
- return lz4ds;
+ (void)inputBuffer;
+ return LZ4_createStream();
}
-char* LZ4_slideInputBuffer (void* LZ4_Data)
+char* LZ4_slideInputBuffer (void* state)
{
- LZ4_stream_t_internal* ctx = &((LZ4_stream_t*)LZ4_Data)->internal_donotuse;
- int dictSize = LZ4_saveDict((LZ4_stream_t*)LZ4_Data, (char*)ctx->bufferStart, 64 KB);
- return (char*)(ctx->bufferStart + dictSize);
+ /* avoid const char * -> char * conversion warning */
+ return (char *)(uptrval)((LZ4_stream_t*)state)->internal_donotuse.dictionary;
}
-/* Obsolete streaming decompression functions */
-
-int LZ4_decompress_safe_withPrefix64k(const char* source, char* dest, int compressedSize, int maxOutputSize)
-{
- return LZ4_decompress_generic(source, dest, compressedSize, maxOutputSize, endOnInputSize, full, 0, withPrefix64k, (BYTE*)dest - 64 KB, NULL, 64 KB);
-}
-
-int LZ4_decompress_fast_withPrefix64k(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);
-}
-
#endif /* LZ4_COMMONDEFS_ONLY */
Modified: grass/trunk/lib/gis/lz4.h
===================================================================
--- grass/trunk/lib/gis/lz4.h 2018-05-19 15:50:47 UTC (rev 72720)
+++ grass/trunk/lib/gis/lz4.h 2018-05-19 17:05:28 UTC (rev 72721)
@@ -72,24 +72,28 @@
/*
* LZ4_DLL_EXPORT :
* Enable exporting of functions when building a Windows DLL
-* LZ4LIB_API :
+* LZ4LIB_VISIBILITY :
* Control library symbols visibility.
*/
+#ifndef LZ4LIB_VISIBILITY
+# if defined(__GNUC__) && (__GNUC__ >= 4)
+# define LZ4LIB_VISIBILITY __attribute__ ((visibility ("default")))
+# else
+# define LZ4LIB_VISIBILITY
+# endif
+#endif
#if defined(LZ4_DLL_EXPORT) && (LZ4_DLL_EXPORT==1)
-# define LZ4LIB_API __declspec(dllexport)
+# define LZ4LIB_API __declspec(dllexport) LZ4LIB_VISIBILITY
#elif defined(LZ4_DLL_IMPORT) && (LZ4_DLL_IMPORT==1)
-# define LZ4LIB_API __declspec(dllimport) /* It isn't required but allows to generate better code, saving a function pointer load from the IAT and an indirect jump.*/
-#elif defined(__GNUC__) && (__GNUC__ >= 4)
-# define LZ4LIB_API __attribute__ ((__visibility__ ("default")))
+# define LZ4LIB_API __declspec(dllimport) LZ4LIB_VISIBILITY /* It isn't required but allows to generate better code, saving a function pointer load from the IAT and an indirect jump.*/
#else
-# define LZ4LIB_API
+# define LZ4LIB_API LZ4LIB_VISIBILITY
#endif
-
/*------ Version ------*/
#define LZ4_VERSION_MAJOR 1 /* for breaking interface changes */
#define LZ4_VERSION_MINOR 8 /* for new (non-breaking) interface capabilities */
-#define LZ4_VERSION_RELEASE 0 /* for tweaks, bug-fixes, or development */
+#define LZ4_VERSION_RELEASE 2 /* for tweaks, bug-fixes, or development */
#define LZ4_VERSION_NUMBER (LZ4_VERSION_MAJOR *100*100 + LZ4_VERSION_MINOR *100 + LZ4_VERSION_RELEASE)
@@ -98,8 +102,8 @@
#define LZ4_EXPAND_AND_QUOTE(str) LZ4_QUOTE(str)
#define LZ4_VERSION_STRING LZ4_EXPAND_AND_QUOTE(LZ4_LIB_VERSION)
-LZ4LIB_API int LZ4_versionNumber (void); /**< library version number; to be used when checking dll version */
-LZ4LIB_API const char* LZ4_versionString (void); /**< library version string; to be used when checking dll version */
+LZ4LIB_API int LZ4_versionNumber (void); /**< library version number; useful to check dll version */
+LZ4LIB_API const char* LZ4_versionString (void); /**< library version string; unseful to check dll version */
/*-************************************
@@ -109,7 +113,7 @@
* LZ4_MEMORY_USAGE :
* Memory usage formula : N->2^N Bytes (examples : 10 -> 1KB; 12 -> 4KB ; 16 -> 64KB; 20 -> 1MB; etc.)
* Increasing memory usage improves compression ratio
- * Reduced memory usage can improve speed, due to cache effect
+ * Reduced memory usage may improve speed, thanks to cache effect
* Default value is 14, for 16KB, which nicely fits into Intel x86 L1 cache
*/
#ifndef LZ4_MEMORY_USAGE
@@ -120,30 +124,29 @@
* Simple Functions
**************************************/
/*! LZ4_compress_default() :
- Compresses 'sourceSize' bytes from buffer 'source'
- into already allocated 'dest' buffer of size 'maxDestSize'.
- Compression is guaranteed to succeed if 'maxDestSize' >= LZ4_compressBound(sourceSize).
+ Compresses 'srcSize' bytes from buffer 'src'
+ into already allocated 'dst' buffer of size 'dstCapacity'.
+ Compression is guaranteed to succeed if 'dstCapacity' >= LZ4_compressBound(srcSize).
It also runs faster, so it's a recommended setting.
- If the function cannot compress 'source' into a more limited 'dest' budget,
+ If the function cannot compress 'src' into a more limited 'dst' budget,
compression stops *immediately*, and the function result is zero.
- As a consequence, 'dest' content is not valid.
- This function never writes outside 'dest' buffer, nor read outside 'source' buffer.
- sourceSize : Max supported value is LZ4_MAX_INPUT_VALUE
- maxDestSize : full or partial size of buffer 'dest' (which must be already allocated)
- return : the number of bytes written into buffer 'dest' (necessarily <= maxOutputSize)
- or 0 if compression fails */
-LZ4LIB_API int LZ4_compress_default(const char* source, char* dest, int sourceSize, int maxDestSize);
+ Note : as a consequence, 'dst' content is not valid.
+ Note 2 : This function is protected against buffer overflow scenarios (never writes outside 'dst' buffer, nor read outside 'source' buffer).
+ srcSize : max supported value is LZ4_MAX_INPUT_SIZE.
+ dstCapacity : size of buffer 'dst' (which must be already allocated)
+ return : the number of bytes written into buffer 'dst' (necessarily <= dstCapacity)
+ or 0 if compression fails */
+LZ4LIB_API int LZ4_compress_default(const char* src, char* dst, int srcSize, int dstCapacity);
/*! LZ4_decompress_safe() :
- compressedSize : is the precise full size of the compressed block.
- maxDecompressedSize : is the size of destination buffer, which must be already allocated.
- return : the number of bytes decompressed into destination buffer (necessarily <= maxDecompressedSize)
- If destination buffer is not large enough, decoding will stop and output an error code (<0).
+ compressedSize : is the exact complete size of the compressed block.
+ dstCapacity : is the size of destination buffer, which must be already allocated.
+ return : the number of bytes decompressed into destination buffer (necessarily <= dstCapacity)
+ If destination buffer is not large enough, decoding will stop and output an error code (negative value).
If the source stream is detected malformed, the function will stop decoding and return a negative result.
- This function is protected against buffer overflow exploits, including malicious data packets.
- It never writes outside output buffer, nor reads outside input buffer.
+ This function is protected against malicious data packets.
*/
-LZ4LIB_API int LZ4_decompress_safe (const char* source, char* dest, int compressedSize, int maxDecompressedSize);
+LZ4LIB_API int LZ4_decompress_safe (const char* src, char* dst, int compressedSize, int dstCapacity);
/*-************************************
@@ -157,22 +160,22 @@
Provides the maximum size that LZ4 compression may output in a "worst case" scenario (input data not compressible)
This function is primarily useful for memory allocation purposes (destination buffer size).
Macro LZ4_COMPRESSBOUND() is also provided for compilation-time evaluation (stack memory allocation for example).
- Note that LZ4_compress_default() compress faster when dest buffer size is >= LZ4_compressBound(srcSize)
+ Note that LZ4_compress_default() compresses faster when dstCapacity is >= LZ4_compressBound(srcSize)
inputSize : max supported value is LZ4_MAX_INPUT_SIZE
return : maximum output size in a "worst case" scenario
- or 0, if input size is too large ( > LZ4_MAX_INPUT_SIZE)
+ or 0, if input size is incorrect (too large or negative)
*/
LZ4LIB_API int LZ4_compressBound(int inputSize);
/*!
LZ4_compress_fast() :
- Same as LZ4_compress_default(), but allows to select an "acceleration" factor.
+ Same as LZ4_compress_default(), but allows selection of "acceleration" factor.
The larger the acceleration value, the faster the algorithm, but also the lesser the compression.
It's a trade-off. It can be fine tuned, with each successive value providing roughly +~3% to speed.
An acceleration value of "1" is the same as regular LZ4_compress_default()
- Values <= 0 will be replaced by ACCELERATION_DEFAULT (see lz4.c), which is 1.
+ Values <= 0 will be replaced by ACCELERATION_DEFAULT (currently == 1, see lz4.c).
*/
-LZ4LIB_API int LZ4_compress_fast (const char* source, char* dest, int sourceSize, int maxDestSize, int acceleration);
+LZ4LIB_API int LZ4_compress_fast (const char* src, char* dst, int srcSize, int dstCapacity, int acceleration);
/*!
@@ -183,55 +186,59 @@
Then, provide it as 'void* state' to compression function.
*/
LZ4LIB_API int LZ4_sizeofState(void);
-LZ4LIB_API int LZ4_compress_fast_extState (void* state, const char* source, char* dest, int inputSize, int maxDestSize, int acceleration);
+LZ4LIB_API int LZ4_compress_fast_extState (void* state, const char* src, char* dst, int srcSize, int dstCapacity, int acceleration);
/*!
LZ4_compress_destSize() :
- Reverse the logic, by compressing as much data as possible from 'source' buffer
- into already allocated buffer 'dest' of size 'targetDestSize'.
- This function either compresses the entire 'source' content into 'dest' if it's large enough,
- or fill 'dest' buffer completely with as much data as possible from 'source'.
- *sourceSizePtr : will be modified to indicate how many bytes where read from 'source' to fill 'dest'.
- New value is necessarily <= old value.
- return : Nb bytes written into 'dest' (necessarily <= targetDestSize)
- or 0 if compression fails
+ Reverse the logic : compresses as much data as possible from 'src' buffer
+ into already allocated buffer 'dst' of size 'targetDestSize'.
+ This function either compresses the entire 'src' content into 'dst' if it's large enough,
+ or fill 'dst' buffer completely with as much data as possible from 'src'.
+ *srcSizePtr : will be modified to indicate how many bytes where read from 'src' to fill 'dst'.
+ New value is necessarily <= old value.
+ return : Nb bytes written into 'dst' (necessarily <= targetDestSize)
+ or 0 if compression fails
*/
-LZ4LIB_API int LZ4_compress_destSize (const char* source, char* dest, int* sourceSizePtr, int targetDestSize);
+LZ4LIB_API int LZ4_compress_destSize (const char* src, char* dst, int* srcSizePtr, int targetDstSize);
/*!
-LZ4_decompress_fast() :
- originalSize : is the original and therefore uncompressed size
- return : the number of bytes read from the source buffer (in other words, the compressed size)
- If the source stream is detected malformed, the function will stop decoding and return a negative result.
- Destination buffer must be already allocated. Its size must be a minimum of 'originalSize' bytes.
- note : This function fully respect memory boundaries for properly formed compressed data.
- It is a bit faster than LZ4_decompress_safe().
- However, it does not provide any protection against intentionally modified data stream (malicious input).
- Use this function in trusted environment only (data to decode comes from a trusted source).
+LZ4_decompress_fast() : **unsafe!**
+This function is a bit faster than LZ4_decompress_safe(),
+but it may misbehave on malformed input because it doesn't perform full validation of compressed data.
+ originalSize : is the uncompressed size to regenerate
+ Destination buffer must be already allocated, and its size must be >= 'originalSize' bytes.
+ return : number of bytes read from source buffer (== compressed size).
+ If the source stream is detected malformed, the function stops decoding and return a negative result.
+ note : This function is only usable if the originalSize of uncompressed data is known in advance.
+ The caller should also check that all the compressed input has been consumed properly,
+ i.e. that the return value matches the size of the buffer with compressed input.
+ The function never writes past the output buffer. However, since it doesn't know its 'src' size,
+ it may read past the intended input. Also, because match offsets are not validated during decoding,
+ reads from 'src' may underflow. Use this function in trusted environment **only**.
*/
-LZ4LIB_API int LZ4_decompress_fast (const char* source, char* dest, int originalSize);
+LZ4LIB_API int LZ4_decompress_fast (const char* src, char* dst, int originalSize);
/*!
LZ4_decompress_safe_partial() :
- This function decompress a compressed block of size 'compressedSize' at position 'source'
- into destination buffer 'dest' of size 'maxDecompressedSize'.
- The function tries to stop decompressing operation as soon as 'targetOutputSize' has been reached,
- reducing decompression time.
- return : the number of bytes decoded in the destination buffer (necessarily <= maxDecompressedSize)
- Note : this number can be < 'targetOutputSize' should the compressed block to decode be smaller.
- Always control how many bytes were decoded.
- If the source stream is detected malformed, the function will stop decoding and return a negative result.
- This function never writes outside of output buffer, and never reads outside of input buffer. It is therefore protected against malicious data packets
+ This function decompress a compressed block of size 'srcSize' at position 'src'
+ into destination buffer 'dst' of size 'dstCapacity'.
+ The function will decompress a minimum of 'targetOutputSize' bytes, and stop after that.
+ However, it's not accurate, and may write more than 'targetOutputSize' (but always <= dstCapacity).
+ @return : the number of bytes decoded in the destination buffer (necessarily <= dstCapacity)
+ Note : this number can also be < targetOutputSize, if compressed block contains less data.
+ Therefore, always control how many bytes were decoded.
+ If source stream is detected malformed, function returns a negative result.
+ This function is protected against malicious data packets.
*/
-LZ4LIB_API int LZ4_decompress_safe_partial (const char* source, char* dest, int compressedSize, int targetOutputSize, int maxDecompressedSize);
+LZ4LIB_API int LZ4_decompress_safe_partial (const char* src, char* dst, int srcSize, int targetOutputSize, int dstCapacity);
/*-*********************************************
* Streaming Compression Functions
***********************************************/
-typedef union LZ4_stream_u LZ4_stream_t; /* incomplete type (defined later) */
+typedef union LZ4_stream_u LZ4_stream_t; /* incomplete type (defined later) */
/*! LZ4_createStream() and LZ4_freeStream() :
* LZ4_createStream() will allocate and initialize an `LZ4_stream_t` structure.
@@ -242,35 +249,44 @@
/*! LZ4_resetStream() :
* An LZ4_stream_t structure can be allocated once and re-used multiple times.
- * Use this function to init an allocated `LZ4_stream_t` structure and start a new compression.
+ * Use this function to start compressing a new stream.
*/
LZ4LIB_API void LZ4_resetStream (LZ4_stream_t* streamPtr);
/*! LZ4_loadDict() :
- * Use this function to load a static dictionary into LZ4_stream.
+ * Use this function to load a static dictionary into LZ4_stream_t.
* Any previous data will be forgotten, only 'dictionary' will remain in memory.
- * Loading a size of 0 is allowed.
- * Return : dictionary size, in bytes (necessarily <= 64 KB)
+ * Loading a size of 0 is allowed, and is the same as reset.
+ * @return : dictionary size, in bytes (necessarily <= 64 KB)
*/
LZ4LIB_API int LZ4_loadDict (LZ4_stream_t* streamPtr, const char* dictionary, int dictSize);
/*! LZ4_compress_fast_continue() :
- * Compress buffer content 'src', using data from previously compressed blocks as dictionary to improve compression ratio.
- * Important : Previous data blocks are assumed to remain present and unmodified !
+ * Compress 'src' content using data from previously compressed blocks, for better compression ratio.
* 'dst' buffer must be already allocated.
* If dstCapacity >= LZ4_compressBound(srcSize), compression is guaranteed to succeed, and runs faster.
- * If not, and if compressed data cannot fit into 'dst' buffer size, compression stops, and function @return==0.
+ *
+ * Important : The previous 64KB of compressed data is assumed to remain present and unmodified in memory!
+ *
+ * Special 1 : When input is a double-buffer, they can have any size, including < 64 KB.
+ * Make sure that buffers are separated by at least one byte.
+ * This way, each block only depends on previous block.
+ * Special 2 : If input buffer is a ring-buffer, it can have any size, including < 64 KB.
+ *
+ * @return : size of compressed block
+ * or 0 if there is an error (typically, cannot fit into 'dst').
* After an error, the stream status is invalid, it can only be reset or freed.
*/
LZ4LIB_API int LZ4_compress_fast_continue (LZ4_stream_t* streamPtr, const char* src, char* dst, int srcSize, int dstCapacity, int acceleration);
/*! LZ4_saveDict() :
- * If previously compressed data block is not guaranteed to remain available at its current memory location,
+ * If last 64KB data cannot be guaranteed to remain available at its current memory location,
* save it into a safer place (char* safeBuffer).
- * Note : it's not necessary to call LZ4_loadDict() after LZ4_saveDict(), dictionary is immediately usable.
- * @return : saved dictionary size in bytes (necessarily <= dictSize), or 0 if error.
+ * This is schematically equivalent to a memcpy() followed by LZ4_loadDict(),
+ * but is much faster, because LZ4_saveDict() doesn't need to rebuild tables.
+ * @return : saved dictionary size in bytes (necessarily <= maxDictSize), or 0 if error.
*/
-LZ4LIB_API int LZ4_saveDict (LZ4_stream_t* streamPtr, char* safeBuffer, int dictSize);
+LZ4LIB_API int LZ4_saveDict (LZ4_stream_t* streamPtr, char* safeBuffer, int maxDictSize);
/*-**********************************************
@@ -277,38 +293,65 @@
* Streaming Decompression Functions
* Bufferless synchronous API
************************************************/
-typedef union LZ4_streamDecode_u LZ4_streamDecode_t; /* incomplete type (defined later) */
+typedef union LZ4_streamDecode_u LZ4_streamDecode_t; /* tracking context */
/*! LZ4_createStreamDecode() and LZ4_freeStreamDecode() :
- * creation / destruction of streaming decompression tracking structure */
+ * creation / destruction of streaming decompression tracking context.
+ * A tracking context can be re-used multiple times.
+ */
LZ4LIB_API LZ4_streamDecode_t* LZ4_createStreamDecode(void);
LZ4LIB_API int LZ4_freeStreamDecode (LZ4_streamDecode_t* LZ4_stream);
/*! LZ4_setStreamDecode() :
- * Use this function to instruct where to find the dictionary.
- * Setting a size of 0 is allowed (same effect as reset).
- * @return : 1 if OK, 0 if error
+ * An LZ4_streamDecode_t context can be allocated once and re-used multiple times.
+ * Use this function to start decompression of a new stream of blocks.
+ * A dictionary can optionnally be set. Use NULL or size 0 for a reset order.
+ * Dictionary is presumed stable : it must remain accessible and unmodified during next decompression.
+ * @return : 1 if OK, 0 if error
*/
LZ4LIB_API int LZ4_setStreamDecode (LZ4_streamDecode_t* LZ4_streamDecode, const char* dictionary, int dictSize);
+/*! LZ4_decoderRingBufferSize() : v1.8.2
+ * Note : in a ring buffer scenario (optional),
+ * blocks are presumed decompressed next to each other
+ * up to the moment there is not enough remaining space for next block (remainingSize < maxBlockSize),
+ * at which stage it resumes from beginning of ring buffer.
+ * When setting such a ring buffer for streaming decompression,
+ * provides the minimum size of this ring buffer
+ * to be compatible with any source respecting maxBlockSize condition.
+ * @return : minimum ring buffer size,
+ * or 0 if there is an error (invalid maxBlockSize).
+ */
+LZ4LIB_API int LZ4_decoderRingBufferSize(int maxBlockSize);
+#define LZ4_DECODER_RING_BUFFER_SIZE(mbs) (65536 + 14 + (mbs)) /* for static allocation; mbs presumed valid */
+
/*! LZ4_decompress_*_continue() :
- * These decoding functions allow decompression of multiple blocks in "streaming" mode.
- * Previously decoded blocks *must* remain available at the memory position where they were decoded (up to 64 KB)
- * In the case of a ring buffers, decoding buffer must be either :
- * - Exactly same size as encoding buffer, with same update rule (block boundaries at same positions)
- * In which case, the decoding & encoding ring buffer can have any size, including very small ones ( < 64 KB).
- * - Larger than encoding buffer, by a minimum of maxBlockSize more bytes.
- * maxBlockSize is implementation dependent. It's the maximum size you intend to compress into a single block.
+ * These decoding functions allow decompression of consecutive blocks in "streaming" mode.
+ * A block is an unsplittable entity, it must be presented entirely to a decompression function.
+ * Decompression functions only accepts one block at a time.
+ * The last 64KB of previously decoded data *must* remain available and unmodified at the memory position where they were decoded.
+ * If less than 64KB of data has been decoded, all the data must be present.
+ *
+ * Special : if decompression side sets a ring buffer, it must respect one of the following conditions :
+ * - Decompression buffer size is _at least_ LZ4_decoderRingBufferSize(maxBlockSize).
+ * maxBlockSize is the maximum size of any single block. It can have any value > 16 bytes.
+ * In which case, encoding and decoding buffers do not need to be synchronized.
+ * Actually, data can be produced by any source compliant with LZ4 format specification, and respecting maxBlockSize.
+ * - Synchronized mode :
+ * Decompression buffer size is _exactly_ the same as compression buffer size,
+ * and follows exactly same update rule (block boundaries at same positions),
+ * and decoding function is provided with exact decompressed size of each block (exception for last block of the stream),
+ * _then_ decoding & encoding ring buffer can have any size, including small ones ( < 64 KB).
+ * - Decompression buffer is larger than encoding buffer, by a minimum of maxBlockSize more bytes.
* In which case, encoding and decoding buffers do not need to be synchronized,
* and encoding ring buffer can have any size, including small ones ( < 64 KB).
- * - _At least_ 64 KB + 8 bytes + maxBlockSize.
- * In which case, encoding and decoding buffers do not need to be synchronized,
- * and encoding ring buffer can have any size, including larger than decoding buffer.
- * Whenever these conditions are not possible, save the last 64KB of decoded data into a safe buffer,
- * and indicate where it is saved using LZ4_setStreamDecode()
+ *
+ * Whenever these conditions are not possible,
+ * save the last 64KB of decoded data into a safe buffer where it can't be modified during decompression,
+ * then indicate where this data is saved using LZ4_setStreamDecode(), before decompressing next block.
*/
-LZ4LIB_API int LZ4_decompress_safe_continue (LZ4_streamDecode_t* LZ4_streamDecode, const char* source, char* dest, int compressedSize, int maxDecompressedSize);
-LZ4LIB_API int LZ4_decompress_fast_continue (LZ4_streamDecode_t* LZ4_streamDecode, const char* source, char* dest, int originalSize);
+LZ4LIB_API int LZ4_decompress_safe_continue (LZ4_streamDecode_t* LZ4_streamDecode, const char* src, char* dst, int srcSize, int dstCapacity);
+LZ4LIB_API int LZ4_decompress_fast_continue (LZ4_streamDecode_t* LZ4_streamDecode, const char* src, char* dst, int originalSize);
/*! LZ4_decompress_*_usingDict() :
@@ -315,15 +358,104 @@
* These decoding functions work the same as
* a combination of LZ4_setStreamDecode() followed by LZ4_decompress_*_continue()
* They are stand-alone, and don't need an LZ4_streamDecode_t structure.
+ * Dictionary is presumed stable : it must remain accessible and unmodified during next decompression.
*/
-LZ4LIB_API int LZ4_decompress_safe_usingDict (const char* source, char* dest, int compressedSize, int maxDecompressedSize, const char* dictStart, int dictSize);
-LZ4LIB_API int LZ4_decompress_fast_usingDict (const char* source, char* dest, int originalSize, const char* dictStart, int dictSize);
+LZ4LIB_API int LZ4_decompress_safe_usingDict (const char* src, char* dst, int srcSize, int dstCapcity, const char* dictStart, int dictSize);
+LZ4LIB_API int LZ4_decompress_fast_usingDict (const char* src, char* dst, int originalSize, const char* dictStart, int dictSize);
/*^**********************************************
* !!!!!! STATIC LINKING ONLY !!!!!!
***********************************************/
+
/*-************************************
+ * Unstable declarations
+ **************************************
+ * Declarations in this section should be considered unstable.
+ * Use at your own peril, etc., etc.
+ * They may be removed in the future.
+ * Their signatures may change.
+ **************************************/
+
+#ifdef LZ4_STATIC_LINKING_ONLY
+
+/*! LZ4_resetStream_fast() :
+ * Use this, like LZ4_resetStream(), to prepare a context for a new chain of
+ * calls to a streaming API (e.g., LZ4_compress_fast_continue()).
+ *
+ * Note:
+ * Using this in advance of a non- streaming-compression function is redundant,
+ * and potentially bad for performance, since they all perform their own custom
+ * reset internally.
+ *
+ * Differences from LZ4_resetStream():
+ * When an LZ4_stream_t is known to be in a internally coherent state,
+ * it can often be prepared for a new compression with almost no work, only
+ * sometimes falling back to the full, expensive reset that is always required
+ * when the stream is in an indeterminate state (i.e., the reset performed by
+ * LZ4_resetStream()).
+ *
+ * LZ4_streams are guaranteed to be in a valid state when:
+ * - returned from LZ4_createStream()
+ * - reset by LZ4_resetStream()
+ * - memset(stream, 0, sizeof(LZ4_stream_t)), though this is discouraged
+ * - the stream was in a valid state and was reset by LZ4_resetStream_fast()
+ * - the stream was in a valid state and was then used in any compression call
+ * that returned success
+ * - the stream was in an indeterminate state and was used in a compression
+ * call that fully reset the state (e.g., LZ4_compress_fast_extState()) and
+ * that returned success
+ *
+ * When a stream isn't known to be in a valid state, it is not safe to pass to
+ * any fastReset or streaming function. It must first be cleansed by the full
+ * LZ4_resetStream().
+ */
+LZ4LIB_API void LZ4_resetStream_fast (LZ4_stream_t* streamPtr);
+
+/*! LZ4_compress_fast_extState_fastReset() :
+ * A variant of LZ4_compress_fast_extState().
+ *
+ * Using this variant avoids an expensive initialization step. It is only safe
+ * to call if the state buffer is known to be correctly initialized already
+ * (see above comment on LZ4_resetStream_fast() for a definition of "correctly
+ * initialized"). From a high level, the difference is that this function
+ * initializes the provided state with a call to something like
+ * LZ4_resetStream_fast() while LZ4_compress_fast_extState() starts with a
+ * call to LZ4_resetStream().
+ */
+LZ4LIB_API int LZ4_compress_fast_extState_fastReset (void* state, const char* src, char* dst, int srcSize, int dstCapacity, int acceleration);
+
+/*! LZ4_attach_dictionary() :
+ * This is an experimental API that allows for the efficient use of a
+ * static dictionary many times.
+ *
+ * Rather than re-loading the dictionary buffer into a working context before
+ * each compression, or copying a pre-loaded dictionary's LZ4_stream_t into a
+ * working LZ4_stream_t, this function introduces a no-copy setup mechanism,
+ * in which the working stream references the dictionary stream in-place.
+ *
+ * Several assumptions are made about the state of the dictionary stream.
+ * Currently, only streams which have been prepared by LZ4_loadDict() should
+ * be expected to work.
+ *
+ * Alternatively, the provided dictionary stream pointer may be NULL, in which
+ * case any existing dictionary stream is unset.
+ *
+ * If a dictionary is provided, it replaces any pre-existing stream history.
+ * The dictionary contents are the only history that can be referenced and
+ * logically immediately precede the data compressed in the first subsequent
+ * compression call.
+ *
+ * The dictionary will only remain attached to the working stream through the
+ * first compression call, at the end of which it is cleared. The dictionary
+ * stream (and source buffer) must remain in-place / accessible / unchanged
+ * through the completion of the first compression call on the stream.
+ */
+LZ4LIB_API void LZ4_attach_dictionary(LZ4_stream_t *working_stream, const LZ4_stream_t *dictionary_stream);
+
+#endif
+
+/*-************************************
* Private definitions
**************************************
* Do not use these definitions.
@@ -337,14 +469,16 @@
#if defined(__cplusplus) || (defined (__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) /* C99 */)
#include <stdint.h>
-typedef struct {
+typedef struct LZ4_stream_t_internal LZ4_stream_t_internal;
+struct LZ4_stream_t_internal {
uint32_t hashTable[LZ4_HASH_SIZE_U32];
uint32_t currentOffset;
- uint32_t initCheck;
+ uint16_t initCheck;
+ uint16_t tableType;
const uint8_t* dictionary;
- uint8_t* bufferStart; /* obsolete, used for slideInputBuffer */
+ const LZ4_stream_t_internal* dictCtx;
uint32_t dictSize;
-} LZ4_stream_t_internal;
+};
typedef struct {
const uint8_t* externalDict;
@@ -355,14 +489,16 @@
#else
-typedef struct {
+typedef struct LZ4_stream_t_internal LZ4_stream_t_internal;
+struct LZ4_stream_t_internal {
unsigned int hashTable[LZ4_HASH_SIZE_U32];
unsigned int currentOffset;
- unsigned int initCheck;
+ unsigned short initCheck;
+ unsigned short tableType;
const unsigned char* dictionary;
- unsigned char* bufferStart; /* obsolete, used for slideInputBuffer */
+ const LZ4_stream_t_internal* dictCtx;
unsigned int dictSize;
-} LZ4_stream_t_internal;
+};
typedef struct {
const unsigned char* externalDict;
@@ -434,26 +570,34 @@
#endif /* LZ4_DISABLE_DEPRECATE_WARNINGS */
/* Obsolete compression functions */
-LZ4LIB_API LZ4_DEPRECATED("use LZ4_compress_default() instead") int LZ4_compress (const char* source, char* dest, int sourceSize);
-LZ4LIB_API LZ4_DEPRECATED("use LZ4_compress_default() instead") int LZ4_compress_limitedOutput (const char* source, char* dest, int sourceSize, int maxOutputSize);
-LZ4LIB_API LZ4_DEPRECATED("use LZ4_compress_fast_extState() instead") int LZ4_compress_withState (void* state, const char* source, char* dest, int inputSize);
-LZ4LIB_API LZ4_DEPRECATED("use LZ4_compress_fast_extState() instead") int LZ4_compress_limitedOutput_withState (void* state, const char* source, char* dest, int inputSize, int maxOutputSize);
-LZ4LIB_API LZ4_DEPRECATED("use LZ4_compress_fast_continue() instead") int LZ4_compress_continue (LZ4_stream_t* LZ4_streamPtr, const char* source, char* dest, int inputSize);
-LZ4LIB_API LZ4_DEPRECATED("use LZ4_compress_fast_continue() instead") int LZ4_compress_limitedOutput_continue (LZ4_stream_t* LZ4_streamPtr, const char* source, char* dest, int inputSize, int maxOutputSize);
+LZ4_DEPRECATED("use LZ4_compress_default() instead") LZ4LIB_API int LZ4_compress (const char* source, char* dest, int sourceSize);
+LZ4_DEPRECATED("use LZ4_compress_default() instead") LZ4LIB_API int LZ4_compress_limitedOutput (const char* source, char* dest, int sourceSize, int maxOutputSize);
+LZ4_DEPRECATED("use LZ4_compress_fast_extState() instead") LZ4LIB_API int LZ4_compress_withState (void* state, const char* source, char* dest, int inputSize);
+LZ4_DEPRECATED("use LZ4_compress_fast_extState() instead") LZ4LIB_API int LZ4_compress_limitedOutput_withState (void* state, const char* source, char* dest, int inputSize, int maxOutputSize);
+LZ4_DEPRECATED("use LZ4_compress_fast_continue() instead") LZ4LIB_API int LZ4_compress_continue (LZ4_stream_t* LZ4_streamPtr, const char* source, char* dest, int inputSize);
+LZ4_DEPRECATED("use LZ4_compress_fast_continue() instead") LZ4LIB_API int LZ4_compress_limitedOutput_continue (LZ4_stream_t* LZ4_streamPtr, const char* source, char* dest, int inputSize, int maxOutputSize);
/* Obsolete decompression functions */
-LZ4LIB_API LZ4_DEPRECATED("use LZ4_decompress_fast() instead") int LZ4_uncompress (const char* source, char* dest, int outputSize);
-LZ4LIB_API LZ4_DEPRECATED("use LZ4_decompress_safe() instead") int LZ4_uncompress_unknownOutputSize (const char* source, char* dest, int isize, int maxOutputSize);
+LZ4_DEPRECATED("use LZ4_decompress_fast() instead") LZ4LIB_API int LZ4_uncompress (const char* source, char* dest, int outputSize);
+LZ4_DEPRECATED("use LZ4_decompress_safe() instead") LZ4LIB_API int LZ4_uncompress_unknownOutputSize (const char* source, char* dest, int isize, int maxOutputSize);
-/* Obsolete streaming functions; use new streaming interface whenever possible */
-LZ4LIB_API LZ4_DEPRECATED("use LZ4_createStream() instead") void* LZ4_create (char* inputBuffer);
-LZ4LIB_API LZ4_DEPRECATED("use LZ4_createStream() instead") int LZ4_sizeofStreamState(void);
-LZ4LIB_API LZ4_DEPRECATED("use LZ4_resetStream() instead") int LZ4_resetStreamState(void* state, char* inputBuffer);
-LZ4LIB_API LZ4_DEPRECATED("use LZ4_saveDict() instead") char* LZ4_slideInputBuffer (void* state);
+/* Obsolete streaming functions; degraded functionality; do not use!
+ *
+ * In order to perform streaming compression, these functions depended on data
+ * that is no longer tracked in the state. They have been preserved as well as
+ * possible: using them will still produce a correct output. However, they don't
+ * actually retain any history between compression calls. The compression ratio
+ * achieved will therefore be no better than compressing each chunk
+ * independently.
+ */
+LZ4_DEPRECATED("Use LZ4_createStream() instead") LZ4LIB_API void* LZ4_create (char* inputBuffer);
+LZ4_DEPRECATED("Use LZ4_createStream() instead") LZ4LIB_API int LZ4_sizeofStreamState(void);
+LZ4_DEPRECATED("Use LZ4_resetStream() instead") LZ4LIB_API int LZ4_resetStreamState(void* state, char* inputBuffer);
+LZ4_DEPRECATED("Use LZ4_saveDict() instead") LZ4LIB_API char* LZ4_slideInputBuffer (void* state);
/* Obsolete streaming decoding functions */
-LZ4LIB_API LZ4_DEPRECATED("use LZ4_decompress_safe_usingDict() instead") int LZ4_decompress_safe_withPrefix64k (const char* src, char* dst, int compressedSize, int maxDstSize);
-LZ4LIB_API LZ4_DEPRECATED("use LZ4_decompress_fast_usingDict() instead") int LZ4_decompress_fast_withPrefix64k (const char* src, char* dst, int originalSize);
+LZ4_DEPRECATED("use LZ4_decompress_safe_usingDict() instead") LZ4LIB_API int LZ4_decompress_safe_withPrefix64k (const char* src, char* dst, int compressedSize, int maxDstSize);
+LZ4_DEPRECATED("use LZ4_decompress_fast_usingDict() instead") LZ4LIB_API int LZ4_decompress_fast_withPrefix64k (const char* src, char* dst, int originalSize);
#endif /* LZ4_H_2983827168210 */
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