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authorW. Felix Handte <w@felixhandte.com>2018-04-26 19:42:16 (GMT)
committerW. Felix Handte <w@felixhandte.com>2018-04-26 22:01:08 (GMT)
commit0858362f28195bb1d88bfa60075d3ec19ff73a9c (patch)
treebb5d4389ee7298230743f8b335eb76ef875c1c10 /lib
parent2becd69bb1b29be8b1414c8ef6cc6269bb184f58 (diff)
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Merge _destSize Compress Variant into LZ4_compress_generic()
Diffstat (limited to 'lib')
-rw-r--r--lib/lz4.c256
1 files changed, 66 insertions, 190 deletions
diff --git a/lib/lz4.c b/lib/lz4.c
index eaabe5b..b4d3140 100644
--- a/lib/lz4.c
+++ b/lib/lz4.c
@@ -453,7 +453,7 @@ static const U32 LZ4_skipTrigger = 6; /* Increase this value ==> compression ru
/*-************************************
* Local Structures and types
**************************************/
-typedef enum { notLimited = 0, limitedOutput = 1 } limitedOutput_directive;
+typedef enum { notLimited = 0, limitedOutput = 1, fillOutput = 2 } limitedOutput_directive;
typedef enum { clearedTable = 0, byPtr, byU32, byU16 } tableType_t;
/**
@@ -637,6 +637,7 @@ LZ4_FORCE_INLINE int LZ4_compress_generic(
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,
@@ -679,6 +680,7 @@ LZ4_FORCE_INLINE int LZ4_compress_generic(
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) */
if (tableType==byPtr) assert(dictDirective==noDict); /* only supported use case with byPtr */
assert(acceleration >= 1);
@@ -795,9 +797,14 @@ LZ4_FORCE_INLINE int LZ4_compress_generic(
/* 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);
@@ -822,6 +829,13 @@ _next_match:
* - 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 */
if (maybe_extMem) { /* static test */
DEBUGLOG(6, " with offset=%u (ext if > %i)", offset, (int)(ip - (const BYTE*)source));
@@ -855,9 +869,17 @@ _next_match:
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;
@@ -939,10 +961,17 @@ _next_match:
_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;
@@ -952,9 +981,13 @@ _last_literals:
*op++ = (BYTE)(lastRun<<ML_BITS);
}
memcpy(op, anchor, lastRun);
+ ip = anchor + lastRun;
op += lastRun;
}
+ if (outputLimited == fillOutput) {
+ *inputConsumed = (int) (((const char*)ip)-source);
+ }
return (int)(((char*)op) - dest);
}
@@ -966,17 +999,17 @@ int LZ4_compress_fast_extState(void* state, const char* source, char* dest, int
LZ4_resetStream((LZ4_stream_t*)state);
if (maxOutputSize >= LZ4_compressBound(inputSize)) {
if (inputSize < LZ4_64Klimit) {
- return LZ4_compress_generic(ctx, source, dest, inputSize, 0, notLimited, byU16, noDict, noDictIssue, acceleration);
+ 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, 0, notLimited, tableType, noDict, noDictIssue, acceleration);
+ 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, maxOutputSize, limitedOutput, byU16, noDict, noDictIssue, acceleration);
+ 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, maxOutputSize, limitedOutput, tableType, noDict, noDictIssue, acceleration);
+ return LZ4_compress_generic(ctx, source, dest, inputSize, NULL, maxOutputSize, limitedOutput, tableType, noDict, noDictIssue, acceleration);
}
}
}
@@ -1000,28 +1033,28 @@ int LZ4_compress_fast_extState_fastReset(void* state, const char* src, char* dst
const tableType_t tableType = byU16;
LZ4_prepareTable(ctx, srcSize, tableType);
if (ctx->currentOffset) {
- return LZ4_compress_generic(ctx, src, dst, srcSize, 0, notLimited, tableType, noDict, dictSmall, acceleration);
+ return LZ4_compress_generic(ctx, src, dst, srcSize, NULL, 0, notLimited, tableType, noDict, dictSmall, acceleration);
} else {
- return LZ4_compress_generic(ctx, src, dst, srcSize, 0, notLimited, tableType, noDict, noDictIssue, acceleration);
+ 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, 0, notLimited, tableType, noDict, noDictIssue, acceleration);
+ return LZ4_compress_generic(ctx, src, dst, srcSize, NULL, 0, notLimited, tableType, noDict, noDictIssue, acceleration);
}
} else {
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, dstCapacity, limitedOutput, tableType, noDict, dictSmall, acceleration);
+ return LZ4_compress_generic(ctx, src, dst, srcSize, NULL, dstCapacity, limitedOutput, tableType, noDict, dictSmall, acceleration);
} else {
- return LZ4_compress_generic(ctx, src, dst, srcSize, dstCapacity, limitedOutput, tableType, noDict, noDictIssue, acceleration);
+ 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, dstCapacity, limitedOutput, tableType, noDict, noDictIssue, acceleration);
+ return LZ4_compress_generic(ctx, src, dst, srcSize, NULL, dstCapacity, limitedOutput, tableType, noDict, noDictIssue, acceleration);
}
}
}
@@ -1060,172 +1093,15 @@ int LZ4_compress_fast_force(const char* source, char* dest, int inputSize, int m
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);
-}
-
-
-/*-******************************
-* *_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);
+ return LZ4_compress_generic(&ctx.internal_donotuse, source, dest, inputSize, NULL, maxOutputSize, limitedOutput, sizeof(void*)==8 ? byU32 : byPtr, noDict, noDictIssue, acceleration);
}
+/* 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);
@@ -1234,10 +1110,10 @@ static int LZ4_compress_destSize_extState (LZ4_stream_t* state, const char* src,
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);
+ 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_destSize_generic(&state->internal_donotuse, src, dst, srcSizePtr, targetDstSize, tableType);
+ return LZ4_compress_generic(&state->internal_donotuse, src, dst, *srcSizePtr, srcSizePtr, targetDstSize, fillOutput, tableType, noDict, noDictIssue, 1);
} }
}
@@ -1397,9 +1273,9 @@ int LZ4_compress_fast_continue (LZ4_stream_t* LZ4_stream, const char* source, ch
/* prefix mode : source data follows dictionary */
if (dictEnd == (const BYTE*)source) {
if ((streamPtr->dictSize < 64 KB) && (streamPtr->dictSize < streamPtr->currentOffset))
- return LZ4_compress_generic(streamPtr, source, dest, inputSize, maxOutputSize, limitedOutput, tableType, withPrefix64k, dictSmall, acceleration);
+ return LZ4_compress_generic(streamPtr, source, dest, inputSize, NULL, maxOutputSize, limitedOutput, tableType, withPrefix64k, dictSmall, acceleration);
else
- return LZ4_compress_generic(streamPtr, source, dest, inputSize, maxOutputSize, limitedOutput, tableType, withPrefix64k, noDictIssue, acceleration);
+ return LZ4_compress_generic(streamPtr, source, dest, inputSize, NULL, maxOutputSize, limitedOutput, tableType, withPrefix64k, noDictIssue, acceleration);
}
/* external dictionary mode */
@@ -1417,15 +1293,15 @@ int LZ4_compress_fast_continue (LZ4_stream_t* LZ4_stream, const char* source, ch
* 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, maxOutputSize, limitedOutput, tableType, usingExtDict, noDictIssue, acceleration);
+ result = LZ4_compress_generic(streamPtr, source, dest, inputSize, NULL, maxOutputSize, limitedOutput, tableType, usingExtDict, noDictIssue, acceleration);
} else {
- result = LZ4_compress_generic(streamPtr, source, dest, inputSize, maxOutputSize, limitedOutput, tableType, usingDictCtx, noDictIssue, acceleration);
+ 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, maxOutputSize, limitedOutput, tableType, usingExtDict, dictSmall, acceleration);
+ result = LZ4_compress_generic(streamPtr, source, dest, inputSize, NULL, maxOutputSize, limitedOutput, tableType, usingExtDict, dictSmall, acceleration);
} else {
- result = LZ4_compress_generic(streamPtr, source, dest, inputSize, maxOutputSize, limitedOutput, tableType, usingExtDict, noDictIssue, acceleration);
+ result = LZ4_compress_generic(streamPtr, source, dest, inputSize, NULL, maxOutputSize, limitedOutput, tableType, usingExtDict, noDictIssue, acceleration);
}
}
streamPtr->dictionary = (const BYTE*)source;
@@ -1444,9 +1320,9 @@ int LZ4_compress_forceExtDict (LZ4_stream_t* LZ4_dict, const char* source, char*
LZ4_renormDictT(streamPtr, srcSize);
if ((streamPtr->dictSize < 64 KB) && (streamPtr->dictSize < streamPtr->currentOffset)) {
- result = LZ4_compress_generic(streamPtr, source, dest, srcSize, 0, notLimited, byU32, usingExtDict, dictSmall, 1);
+ result = LZ4_compress_generic(streamPtr, source, dest, srcSize, NULL, 0, notLimited, byU32, usingExtDict, dictSmall, 1);
} else {
- result = LZ4_compress_generic(streamPtr, source, dest, srcSize, 0, notLimited, byU32, usingExtDict, noDictIssue, 1);
+ result = LZ4_compress_generic(streamPtr, source, dest, srcSize, NULL, 0, notLimited, byU32, usingExtDict, noDictIssue, 1);
}
streamPtr->dictionary = (const BYTE*)source;