lib/zstd
1
0
Fork 0
mirror of https://github.com/facebook/zstd.git synced 2025-12-24 17:21:03 +03:00
Code Activity

[examples] Clean up and comment the examples

Browse Source
This commit is contained in:
Nick Terrell
2019-04-05 18:11:17 -07:00
parent 1dfe37fea9
commit 1d0c1707d1
11 changed files with 143 additions and 141 deletions
Download Patch File Download Diff File Expand all files Collapse all files

26
examples/dictionary_compression.c
View File

@@ -7,13 +7,11 @@
* in the COPYING file in the root directory of this source tree).
* You may select, at your option, one of the above-listed licenses.
*/
#include <stdlib.h> // malloc, exit
#include <stdio.h> // printf
#include <string.h> // strerror
#include <errno.h> // errno
#include <sys/stat.h> // stat
#include <stdlib.h> // free
#include <string.h> // memset, strcat
#include <zstd.h> // presumes zstd library is installed
#include "utils.h"
#include "common.h" // Helper functions, CHECK(), and CHECK_ZSTD()
/* createDict() :
`dictFileName` is supposed to have been created using `zstd --train` */
@@ -23,10 +21,7 @@ static ZSTD_CDict* createCDict_orDie(const char* dictFileName, int cLevel)
printf("loading dictionary %s \n", dictFileName);
void* const dictBuffer = mallocAndLoadFile_orDie(dictFileName, &dictSize);
ZSTD_CDict* const cdict = ZSTD_createCDict(dictBuffer, dictSize, cLevel);
if (!cdict) {
fprintf(stderr, "ZSTD_createCDict error \n");
exit(7);
}
CHECK(cdict != NULL, "ZSTD_createCDict() failed!");
free(dictBuffer);
return cdict;
}
@@ -39,13 +34,16 @@ static void compress(const char* fname, const char* oname, const ZSTD_CDict* cdi
size_t const cBuffSize = ZSTD_compressBound(fSize);
void* const cBuff = malloc_orDie(cBuffSize);
/* Compress using the dictionary.
* This function writes the dictionary id, and content size into the header.
* But, it doesn't use a checksum. You can control these options using the
* advanced API: ZSTD_CCtx_setParameter(), ZSTD_CCtx_refCDict(),
* and ZSTD_compress2().
*/
ZSTD_CCtx* const cctx = ZSTD_createCCtx();
if (cctx==NULL) { fprintf(stderr, "ZSTD_createCCtx() error \n"); exit(10); }
CHECK(cctx != NULL, "ZSTD_createCCtx() failed!");
size_t const cSize = ZSTD_compress_usingCDict(cctx, cBuff, cBuffSize, fBuff, fSize, cdict);
if (ZSTD_isError(cSize)) {
fprintf(stderr, "error compressing %s : %s \n", fname, ZSTD_getErrorName(cSize));
exit(7);
}
CHECK_ZSTD(cSize);
saveFile_orDie(oname, cBuff, cSize);