2 * Copyright 2016-present, Yann Collet, Facebook, Inc.
5 * This source code is licensed under the license found in the
6 * LICENSE-examples file in the root directory of this source tree.
9 #include <stdlib.h> // malloc, exit
10 #include <stdio.h> // printf
11 #include <string.h> // strerror
12 #include <errno.h> // errno
13 #include <sys/stat.h> // stat
14 #define ZSTD_STATIC_LINKING_ONLY // ZSTD_findDecompressedSize
15 #include <zstd.h> // presumes zstd library is installed
18 static off_t fsize_orDie(const char *filename)
21 if (stat(filename, &st) == 0) return st.st_size;
23 fprintf(stderr, "stat: %s : %s \n", filename, strerror(errno));
27 static FILE* fopen_orDie(const char *filename, const char *instruction)
29 FILE* const inFile = fopen(filename, instruction);
30 if (inFile) return inFile;
32 fprintf(stderr, "fopen: %s : %s \n", filename, strerror(errno));
36 static void* malloc_orDie(size_t size)
38 void* const buff = malloc(size + !size); /* avoid allocating size of 0 : may return NULL (implementation dependent) */
39 if (buff) return buff;
41 fprintf(stderr, "malloc: %s \n", strerror(errno));
45 static void* loadFile_orDie(const char* fileName, size_t* size)
47 off_t const buffSize = fsize_orDie(fileName);
48 FILE* const inFile = fopen_orDie(fileName, "rb");
49 void* const buffer = malloc_orDie(buffSize);
50 size_t const readSize = fread(buffer, 1, buffSize, inFile);
51 if (readSize != (size_t)buffSize) {
52 fprintf(stderr, "fread: %s : %s \n", fileName, strerror(errno));
55 fclose(inFile); /* can't fail (read only) */
61 static void decompress(const char* fname)
64 void* const cBuff = loadFile_orDie(fname, &cSize);
65 unsigned long long const rSize = ZSTD_findDecompressedSize(cBuff, cSize);
66 if (rSize==ZSTD_CONTENTSIZE_ERROR) {
67 fprintf(stderr, "%s : it was not compressed by zstd.\n", fname);
69 } else if (rSize==ZSTD_CONTENTSIZE_UNKNOWN) {
71 "%s : original size unknown. Use streaming decompression instead.\n", fname);
75 void* const rBuff = malloc_orDie((size_t)rSize);
77 size_t const dSize = ZSTD_decompress(rBuff, rSize, cBuff, cSize);
80 fprintf(stderr, "error decoding %s : %s \n", fname, ZSTD_getErrorName(dSize));
85 printf("%25s : %6u -> %7u \n", fname, (unsigned)cSize, (unsigned)rSize);
92 int main(int argc, const char** argv)
94 const char* const exeName = argv[0];
97 printf("wrong arguments\n");
99 printf("%s FILE\n", exeName);
105 printf("%s correctly decoded (in memory). \n", argv[1]);