AuroraMiddleware/lz4
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simplified output_directive

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This commit is contained in:
Yann Collet 2019-04-15 14:13:10 -07:00
parent 55f6f0dd74
commit 920c988669
1 changed files with 17 additions and 15 deletions
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32
lib/lz4.c
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@ -760,9 +760,9 @@ LZ4_FORCE_INLINE int LZ4_compress_generic(
const char* const source,
char* const dest,
const int inputSize,
int *inputConsumed, /* only written when outputLimited == fillOutput */
int *inputConsumed, /* only written when outputDirective == fillOutput */
const int maxOutputSize,
const limitedOutput_directive outputLimited,
const limitedOutput_directive outputDirective,
const tableType_t tableType,
const dict_directive dictDirective,
const dictIssue_directive dictIssue,
@ -805,7 +805,7 @@ LZ4_FORCE_INLINE int LZ4_compress_generic(
DEBUGLOG(5, "LZ4_compress_generic: srcSize=%i, tableType=%u", inputSize, tableType);
/* If init conditions are not met, we don't have to mark stream
* as having dirty context, since no action was taken yet */
if (outputLimited == fillOutput && maxOutputSize < 1) return 0; /* Impossible to store anything */
if (outputDirective == 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 == 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 */
@ -922,11 +922,11 @@ LZ4_FORCE_INLINE int LZ4_compress_generic(
/* Encode Literals */
{ unsigned const litLength = (unsigned)(ip - anchor);
token = op++;
if ((outputLimited == limitedOutput) && /* Check output buffer overflow */
if ((outputDirective == limitedOutput) && /* Check output buffer overflow */
(unlikely(op + litLength + (2 + 1 + LASTLITERALS) + (litLength/255) > olimit)) )
return 0; /* cannot compress within `dst` budget. Stored indexes in hash table are nonetheless fine */
if ((outputLimited == fillOutput) &&
if ((outputDirective == 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;
@ -955,7 +955,7 @@ _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) &&
if ((outputDirective == 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;
@ -995,16 +995,17 @@ _next_match:
DEBUGLOG(6, " with matchLength=%u", matchCode+MINMATCH);
}
if ((outputLimited) && /* Check output buffer overflow */
if ((outputDirective) && /* Check output buffer overflow */
(unlikely(op + (1 + LASTLITERALS) + (matchCode>>8) > olimit)) ) {
if (outputLimited == fillOutput) {
if (outputDirective == 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 (outputLimited == limitedOutput)
} else {
assert(outputDirective == limitedOutput);
return 0; /* cannot compress within `dst` budget. Stored indexes in hash table are nonetheless fine */
}
}
if (matchCode >= ML_MASK) {
*token += ML_MASK;
@ -1088,16 +1089,17 @@ _next_match:
_last_literals:
/* Encode Last Literals */
{ size_t lastRun = (size_t)(iend - anchor);
if ( (outputLimited) && /* Check output buffer overflow */
if ( (outputDirective) && /* Check output buffer overflow */
(op + lastRun + 1 + ((lastRun+255-RUN_MASK)/255) > olimit)) {
if (outputLimited == fillOutput) {
if (outputDirective == fillOutput) {
/* adapt lastRun to fill 'dst' */
assert(olimit >= op);
lastRun = (size_t)(olimit-op) - 1;
lastRun -= (lastRun+240)/255;
}
if (outputLimited == limitedOutput)
} else {
assert(outputDirective == limitedOutput);
return 0; /* cannot compress within `dst` budget. Stored indexes in hash table are nonetheless fine */
}
}
if (lastRun >= RUN_MASK) {
size_t accumulator = lastRun - RUN_MASK;
@ -1112,7 +1114,7 @@ _last_literals:
op += lastRun;
}
if (outputLimited == fillOutput) {
if (outputDirective == fillOutput) {
*inputConsumed = (int) (((const char*)ip)-source);
}
DEBUGLOG(5, "LZ4_compress_generic: compressed %i bytes into %i bytes", inputSize, (int)(((char*)op) - dest));