From 483eb2f56657e8e7f419ab1a4fab8dce9ade8609 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sat, 27 Apr 2024 20:24:20 +0200 Subject: Adding upstream version 14.2.21. Signed-off-by: Daniel Baumann --- src/zstd/examples/simple_decompression.c | 110 +++++++++++++++++++++++++++++++ 1 file changed, 110 insertions(+) create mode 100644 src/zstd/examples/simple_decompression.c (limited to 'src/zstd/examples/simple_decompression.c') diff --git a/src/zstd/examples/simple_decompression.c b/src/zstd/examples/simple_decompression.c new file mode 100644 index 00000000..c1818a95 --- /dev/null +++ b/src/zstd/examples/simple_decompression.c @@ -0,0 +1,110 @@ +/* + * Copyright (c) 2016-present, Yann Collet, Facebook, Inc. + * All rights reserved. + * + * This source code is licensed under both the BSD-style license (found in the + * LICENSE file in the root directory of this source tree) and the GPLv2 (found + * 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 // malloc, exit +#include // printf +#include // strerror +#include // errno +#include // stat +#define ZSTD_STATIC_LINKING_ONLY // ZSTD_findDecompressedSize +#include // presumes zstd library is installed + + +static off_t fsize_orDie(const char *filename) +{ + struct stat st; + if (stat(filename, &st) == 0) return st.st_size; + /* error */ + fprintf(stderr, "stat: %s : %s \n", filename, strerror(errno)); + exit(1); +} + +static FILE* fopen_orDie(const char *filename, const char *instruction) +{ + FILE* const inFile = fopen(filename, instruction); + if (inFile) return inFile; + /* error */ + fprintf(stderr, "fopen: %s : %s \n", filename, strerror(errno)); + exit(2); +} + +static void* malloc_orDie(size_t size) +{ + void* const buff = malloc(size + !size); /* avoid allocating size of 0 : may return NULL (implementation dependent) */ + if (buff) return buff; + /* error */ + fprintf(stderr, "malloc: %s \n", strerror(errno)); + exit(3); +} + +static void* loadFile_orDie(const char* fileName, size_t* size) +{ + off_t const buffSize = fsize_orDie(fileName); + FILE* const inFile = fopen_orDie(fileName, "rb"); + void* const buffer = malloc_orDie(buffSize); + size_t const readSize = fread(buffer, 1, buffSize, inFile); + if (readSize != (size_t)buffSize) { + fprintf(stderr, "fread: %s : %s \n", fileName, strerror(errno)); + exit(4); + } + fclose(inFile); /* can't fail (read only) */ + *size = buffSize; + return buffer; +} + + +static void decompress(const char* fname) +{ + size_t cSize; + void* const cBuff = loadFile_orDie(fname, &cSize); + unsigned long long const rSize = ZSTD_findDecompressedSize(cBuff, cSize); + if (rSize==ZSTD_CONTENTSIZE_ERROR) { + fprintf(stderr, "%s : it was not compressed by zstd.\n", fname); + exit(5); + } else if (rSize==ZSTD_CONTENTSIZE_UNKNOWN) { + fprintf(stderr, + "%s : original size unknown. Use streaming decompression instead.\n", fname); + exit(6); + } + + void* const rBuff = malloc_orDie((size_t)rSize); + + size_t const dSize = ZSTD_decompress(rBuff, rSize, cBuff, cSize); + + if (dSize != rSize) { + fprintf(stderr, "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 correctly decoded (in memory). \n", argv[1]); + + return 0; +} -- cgit v1.2.3