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Merge pull request #2390 from animalize/clamp_level

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Clamp compression level
This commit is contained in:
Nick Terrell
2020-12-02 14:35:58 -08:00
committed by GitHub
parent a6ee1b3047 52f8c07a3f
commit 894ae36675
1 changed files with 12 additions and 4 deletions
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lib/compress/zstd_compress.c
+12 -4
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@@ -5139,13 +5139,21 @@ static ZSTD_compressionParameters ZSTD_getCParams_internal(int compressionLevel,
{ {
U64 const rSize = ZSTD_getCParamRowSize(srcSizeHint, dictSize, mode); U64 const rSize = ZSTD_getCParamRowSize(srcSizeHint, dictSize, mode);
U32 const tableID = (rSize <= 256 KB) + (rSize <= 128 KB) + (rSize <= 16 KB); U32 const tableID = (rSize <= 256 KB) + (rSize <= 128 KB) + (rSize <= 16 KB);
int row = compressionLevel; int row;
DEBUGLOG(5, "ZSTD_getCParams_internal (cLevel=%i)", compressionLevel); DEBUGLOG(5, "ZSTD_getCParams_internal (cLevel=%i)", compressionLevel);
/* row */
if (compressionLevel == 0) row = ZSTD_CLEVEL_DEFAULT; /* 0 == default */ if (compressionLevel == 0) row = ZSTD_CLEVEL_DEFAULT; /* 0 == default */
if (compressionLevel < 0) row = 0; /* entry 0 is baseline for fast mode */ else if (compressionLevel < 0) row = 0; /* entry 0 is baseline for fast mode */
if (compressionLevel > ZSTD_MAX_CLEVEL) row = ZSTD_MAX_CLEVEL; else if (compressionLevel > ZSTD_MAX_CLEVEL) row = ZSTD_MAX_CLEVEL;
else row = compressionLevel;
{ ZSTD_compressionParameters cp = ZSTD_defaultCParameters[tableID][row]; { ZSTD_compressionParameters cp = ZSTD_defaultCParameters[tableID][row];
if (compressionLevel < 0) cp.targetLength = (unsigned)(-compressionLevel); /* acceleration factor */ /* acceleration factor */
if (compressionLevel < 0) {
int const clampedCompressionLevel = MAX(ZSTD_minCLevel(), compressionLevel);
cp.targetLength = (unsigned)(-clampedCompressionLevel);
}
/* refine parameters based on srcSize & dictSize */ /* refine parameters based on srcSize & dictSize */
return ZSTD_adjustCParams_internal(cp, srcSizeHint, dictSize, mode); return ZSTD_adjustCParams_internal(cp, srcSizeHint, dictSize, mode);
} }