Zstandard library : usage examples
==================================
+- [Simple compression](simple_compression.c)
+ Compress a single file.
+ Introduces usage of : `ZSTD_compress()`
+
+- [Simple decompression](simple_decompression.c)
+ Decompress a single file compressed by zstd.
+ Introduces usage of : `ZSTD_decompress()`
+
- [Dictionary decompression](dictionary_decompression.c)
Decompress multiple files using the same dictionary.
- Compatible with Legacy modes.
Introduces usage of : `ZSTD_createDDict()` and `ZSTD_decompress_usingDDict()`
-#include <stdlib.h> // exit
+/*
+ Dictionary decompression
+ Educational program using zstd library
+ Copyright (C) Yann Collet 2016
+
+ GPL v2 License
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License along
+ with this program; if not, write to the Free Software Foundation, Inc.,
+ 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+
+ You can contact the author at :
+ - zstd homepage : http://www.zstd.net/
+*/
+
+#include <stdlib.h> // malloc, exit
#include <stdio.h> // printf
#include <string.h> // strerror
#include <errno.h> // errno
#include <sys/stat.h> // stat
-#include <zstd.h>
+#include <zstd.h> // presumes zstd library is installed
-static off_t fsizeX(const char *filename)
+static off_t fsize_X(const char *filename)
{
struct stat st;
if (stat(filename, &st) == 0) return st.st_size;
exit(1);
}
-static FILE* fopenX(const char *filename, const char *instruction)
+static FILE* fopen_X(const char *filename, const char *instruction)
{
FILE* const inFile = fopen(filename, instruction);
if (inFile) return inFile;
exit(2);
}
-static void* mallocX(size_t size)
+static void* malloc_X(size_t size)
{
void* const buff = malloc(size);
if (buff) return buff;
exit(3);
}
-static void* loadFileX(const char* fileName, size_t* size)
+static void* loadFile_X(const char* fileName, size_t* size)
{
- off_t const buffSize = fsizeX(fileName);
- FILE* const inFile = fopenX(fileName, "rb");
- void* const buffer = mallocX(buffSize);
+ off_t const buffSize = fsize_X(fileName);
+ FILE* const inFile = fopen_X(fileName, "rb");
+ void* const buffer = malloc_X(buffSize);
size_t const readSize = fread(buffer, 1, buffSize, inFile);
if (readSize != (size_t)buffSize) {
printf("fread: %s : %s \n", fileName, strerror(errno));
static const ZSTD_DDict* createDict(const char* dictFileName)
{
size_t dictSize;
- void* const dictBuffer = loadFileX(dictFileName, &dictSize);
+ void* const dictBuffer = loadFile_X(dictFileName, &dictSize);
const ZSTD_DDict* const ddict = ZSTD_createDDict(dictBuffer, dictSize);
free(dictBuffer);
return ddict;
static void decompress(const char* fname, const ZSTD_DDict* ddict)
{
size_t cSize;
- void* const cBuff = loadFileX(fname, &cSize);
+ void* const cBuff = loadFile_X(fname, &cSize);
unsigned long long const rSize = ZSTD_getDecompressedSize(cBuff, cSize);
if (rSize==0) {
printf("%s : original size unknown \n", fname);
exit(5);
}
- void* const rBuff = mallocX(rSize);
+ void* const rBuff = malloc_X(rSize);
ZSTD_DCtx* const dctx = ZSTD_createDCtx();
size_t const dSize = ZSTD_decompress_usingDDict(dctx, rBuff, rSize, cBuff, cSize, ddict);
--- /dev/null
+/*
+ Simple compression
+ Educational program using zstd library
+ Copyright (C) Yann Collet 2016
+
+ GPL v2 License
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License along
+ with this program; if not, write to the Free Software Foundation, Inc.,
+ 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+
+ You can contact the author at :
+ - zstd homepage : http://www.zstd.net/
+*/
+
+#include <stdlib.h> // malloc, exit
+#include <stdio.h> // printf
+#include <string.h> // strerror
+#include <errno.h> // errno
+#include <sys/stat.h> // stat
+#include <zstd.h> // presumes zstd library is installed
+
+
+static off_t fsize_X(const char *filename)
+{
+ struct stat st;
+ if (stat(filename, &st) == 0) return st.st_size;
+ /* error */
+ printf("stat: %s : %s \n", filename, strerror(errno));
+ exit(1);
+}
+
+static FILE* fopen_X(const char *filename, const char *instruction)
+{
+ FILE* const inFile = fopen(filename, instruction);
+ if (inFile) return inFile;
+ /* error */
+ printf("fopen: %s : %s \n", filename, strerror(errno));
+ exit(2);
+}
+
+static void* malloc_X(size_t size)
+{
+ void* const buff = malloc(size);
+ if (buff) return buff;
+ /* error */
+ printf("malloc: %s \n", strerror(errno));
+ exit(3);
+}
+
+static void* loadFile_X(const char* fileName, size_t* size)
+{
+ off_t const buffSize = fsize_X(fileName);
+ FILE* const inFile = fopen_X(fileName, "rb");
+ void* const buffer = malloc_X(buffSize);
+ size_t const readSize = fread(buffer, 1, buffSize, inFile);
+ if (readSize != (size_t)buffSize) {
+ printf("fread: %s : %s \n", fileName, strerror(errno));
+ exit(4);
+ }
+ fclose(inFile);
+ *size = buffSize;
+ return buffer;
+}
+
+
+static void compress(const char* fname)
+{
+ size_t fSize;
+ void* const fBuff = loadFile_X(fname, &fSize);
+ size_t const cBuffSize = ZSTD_compressBound(fSize);
+ void* const cBuff = malloc_X(cBuffSize);
+
+ size_t const cSize = ZSTD_compress(cBuff, cBuffSize, fBuff, fSize, 1);
+ if (ZSTD_isError(cSize)) {
+ printf("error compressing %s : %s \n", fname, ZSTD_getErrorName(cSize));
+ exit(7);
+ }
+
+ /* success */
+ printf("%25s : %6u -> %7u \n", fname, (unsigned)fSize, (unsigned)cSize);
+
+ free(fBuff);
+ free(cBuff);
+}
+
+
+int main(int argc, const char** argv)
+{
+ const char* const exeName = argv[0];
+
+ if (argc!=2) {
+ printf("wrong arguments\n");
+ printf("usage:\n");
+ printf("%s FILE\n", exeName);
+ return 1;
+ }
+
+ compress(argv[1]);
+
+ printf("%s compressed. \n", argv[1]);
+}
--- /dev/null
+/*
+ Simple decompression
+ Educational program using zstd library
+ Copyright (C) Yann Collet 2016
+
+ GPL v2 License
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License along
+ with this program; if not, write to the Free Software Foundation, Inc.,
+ 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+
+ You can contact the author at :
+ - zstd homepage : http://www.zstd.net/
+*/
+
+#include <stdlib.h> // malloc, exit
+#include <stdio.h> // printf
+#include <string.h> // strerror
+#include <errno.h> // errno
+#include <sys/stat.h> // stat
+#include <zstd.h> // presumes zstd library is installed
+
+
+static off_t fsize_X(const char *filename)
+{
+ struct stat st;
+ if (stat(filename, &st) == 0) return st.st_size;
+ /* error */
+ printf("stat: %s : %s \n", filename, strerror(errno));
+ exit(1);
+}
+
+static FILE* fopen_X(const char *filename, const char *instruction)
+{
+ FILE* const inFile = fopen(filename, instruction);
+ if (inFile) return inFile;
+ /* error */
+ printf("fopen: %s : %s \n", filename, strerror(errno));
+ exit(2);
+}
+
+static void* malloc_X(size_t size)
+{
+ void* const buff = malloc(size);
+ if (buff) return buff;
+ /* error */
+ printf("malloc: %s \n", strerror(errno));
+ exit(3);
+}
+
+static void* loadFile_X(const char* fileName, size_t* size)
+{
+ off_t const buffSize = fsize_X(fileName);
+ FILE* const inFile = fopen_X(fileName, "rb");
+ void* const buffer = malloc_X(buffSize);
+ size_t const readSize = fread(buffer, 1, buffSize, inFile);
+ if (readSize != (size_t)buffSize) {
+ printf("fread: %s : %s \n", fileName, strerror(errno));
+ exit(4);
+ }
+ fclose(inFile);
+ *size = buffSize;
+ return buffer;
+}
+
+
+/* prototype declared here, as it is currently part of experimental section */
+unsigned long long ZSTD_getDecompressedSize(const void* src, size_t srcSize);
+
+static void decompress(const char* fname)
+{
+ size_t cSize;
+ void* const cBuff = loadFile_X(fname, &cSize);
+ unsigned long long const rSize = ZSTD_getDecompressedSize(cBuff, cSize);
+ if (rSize==0) {
+ printf("%s : original size unknown \n", fname);
+ exit(5);
+ }
+ void* const rBuff = malloc_X(rSize);
+
+ size_t const dSize = ZSTD_decompress(rBuff, rSize, cBuff, cSize);
+
+ if (dSize != rSize) {
+ printf("error decoding %s : %s \n", fname, ZSTD_getErrorName(dSize));
+ exit(7);
+ }
+
+ /* success */
+ printf("%25s : %6u -> %7u \n", fname, (unsigned)cSize, (unsigned)rSize);
+
+ free(rBuff);
+ free(cBuff);
+}
+
+
+int main(int argc, const char** argv)
+{
+ const char* const exeName = argv[0];
+
+ if (argc!=2) {
+ printf("wrong arguments\n");
+ printf("usage:\n");
+ printf("%s FILE\n", exeName);
+ return 1;
+ }
+
+ decompress(argv[1]);
+
+ printf("%s decoded. \n", argv[1]);
+}
projects / thirdparty / zstd.git / commitdiff
