ddidderr/zstd-rs
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Adjust advanced parameters to source size

Browse Source 
In the new advanced API, adjust the parameters even if they are explicitly
set. This mainly applies to the `windowLog`, and accordingly the `hashLog`
and `chainLog`, when the source size is known.
This commit is contained in:
Nick Terrell
2018-06-18 15:49:31 -07:00
parent f70f829ff5
commit 3841dbac84
4 changed files with 27 additions and 24 deletions
Download Patch File Download Diff File Expand all files Collapse all files
lib/compress/zstd_ldm.c
+6 -4
View File
@@ -9,6 +9,7 @@
#include "zstd_ldm.h"
#include "debug.h"
#include "zstd_fast.h" /* ZSTD_fillHashTable() */
#include "zstd_double_fast.h" /* ZSTD_fillDoubleHashTable() */
@@ -20,7 +21,7 @@
void ZSTD_ldm_adjustParameters(ldmParams_t* params,
ZSTD_compressionParameters const* cParams)
{
U32 const windowLog = cParams->windowLog;
params->windowLog = cParams->windowLog;
ZSTD_STATIC_ASSERT(LDM_BUCKET_SIZE_LOG <= ZSTD_LDM_BUCKETSIZELOG_MAX);
DEBUGLOG(4, "ZSTD_ldm_adjustParameters");
if (!params->bucketSizeLog) params->bucketSizeLog = LDM_BUCKET_SIZE_LOG;
@@ -33,12 +34,13 @@ void ZSTD_ldm_adjustParameters(ldmParams_t* params,
params->minMatchLength = minMatch;
}
if (params->hashLog == 0) {
params->hashLog = MAX(ZSTD_HASHLOG_MIN, windowLog - LDM_HASH_RLOG);
params->hashLog = MAX(ZSTD_HASHLOG_MIN, params->windowLog - LDM_HASH_RLOG);
assert(params->hashLog <= ZSTD_HASHLOG_MAX);
}
if (params->hashEveryLog == 0) {
params->hashEveryLog =
windowLog < params->hashLog ? 0 : windowLog - params->hashLog;
params->hashEveryLog = params->windowLog < params->hashLog
? 0
: params->windowLog - params->hashLog;
}
params->bucketSizeLog = MIN(params->bucketSizeLog, params->hashLog);
}