facebook/zstd
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Clamp compression level in ZSTD_getCParams_internal() function

Browse Source
This commit is contained in:
animalize 2020-11-14 13:16:27 +08:00
parent 69b8361b0c
commit 52f8c07a3f
1 changed files with 12 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

16
lib/compress/zstd_compress.c
View File

@ -4681,13 +4681,21 @@ 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);
} }