diff --git a/examples/README.md b/examples/README.md index a3d59315e..594e2eaf8 100644 --- a/examples/README.md +++ b/examples/README.md @@ -1,7 +1,14 @@ 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()` diff --git a/examples/dictionary_decompression.c b/examples/dictionary_decompression.c index e307bea5b..c873fa7c3 100644 --- a/examples/dictionary_decompression.c +++ b/examples/dictionary_decompression.c @@ -1,12 +1,37 @@ -#include // 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 // malloc, exit #include // printf #include // strerror #include // errno #include // stat -#include +#include // 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; @@ -15,7 +40,7 @@ static off_t fsizeX(const char *filename) 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; @@ -24,7 +49,7 @@ static FILE* fopenX(const char *filename, const char *instruction) exit(2); } -static void* mallocX(size_t size) +static void* malloc_X(size_t size) { void* const buff = malloc(size); if (buff) return buff; @@ -33,11 +58,11 @@ static void* mallocX(size_t size) 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)); @@ -52,7 +77,7 @@ static void* loadFileX(const char* fileName, size_t* size) 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; @@ -65,13 +90,13 @@ unsigned long long ZSTD_getDecompressedSize(const void* src, size_t srcSize); 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); diff --git a/examples/simple_compression.c b/examples/simple_compression.c new file mode 100644 index 000000000..1b6ef429e --- /dev/null +++ b/examples/simple_compression.c @@ -0,0 +1,112 @@ +/* + 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 // malloc, exit +#include // printf +#include // strerror +#include // errno +#include // stat +#include // 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]); +} diff --git a/examples/simple_decompression.c b/examples/simple_decompression.c new file mode 100644 index 000000000..da4515027 --- /dev/null +++ b/examples/simple_decompression.c @@ -0,0 +1,120 @@ +/* + 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 // malloc, exit +#include // printf +#include // strerror +#include // errno +#include // stat +#include // 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]); +}