1 /* 2 * Copyright (c) 2017-2020, Facebook, Inc. 3 * All rights reserved. 4 * 5 * This source code is licensed under both the BSD-style license (found in the 6 * LICENSE file in the root directory of this source tree) and the GPLv2 (found 7 * in the COPYING file in the root directory of this source tree). 8 * You may select, at your option, one of the above-listed licenses. 9 */ 10 11 #include <stdio.h> 12 #include <stdlib.h> 13 14 #include "zstd_decompress.h" 15 16 typedef unsigned char u8; 17 18 // If the data doesn't have decompressed size with it, fallback on assuming the 19 // compression ratio is at most 16 20 #define MAX_COMPRESSION_RATIO (16) 21 22 // Protect against allocating too much memory for output 23 #define MAX_OUTPUT_SIZE ((size_t)1024 * 1024 * 1024) 24 25 // Error message then exit 26 #define ERR_OUT(...) { fprintf(stderr, __VA_ARGS__); exit(1); } 27 28 29 typedef struct { 30 u8* address; 31 size_t size; 32 } buffer_s; 33 34 static void freeBuffer(buffer_s b) { free(b.address); } 35 36 static buffer_s read_file(const char *path) 37 { 38 FILE* const f = fopen(path, "rb"); 39 if (!f) ERR_OUT("failed to open file %s \n", path); 40 41 fseek(f, 0L, SEEK_END); 42 size_t const size = (size_t)ftell(f); 43 rewind(f); 44 45 void* const ptr = malloc(size); 46 if (!ptr) ERR_OUT("failed to allocate memory to hold %s \n", path); 47 48 size_t const read = fread(ptr, 1, size, f); 49 if (read != size) ERR_OUT("error while reading file %s \n", path); 50 51 fclose(f); 52 buffer_s const b = { ptr, size }; 53 return b; 54 } 55 56 static void write_file(const char* path, const u8* ptr, size_t size) 57 { 58 FILE* const f = fopen(path, "wb"); 59 if (!f) ERR_OUT("failed to open file %s \n", path); 60 61 size_t written = 0; 62 while (written < size) { 63 written += fwrite(ptr+written, 1, size, f); 64 if (ferror(f)) ERR_OUT("error while writing file %s\n", path); 65 } 66 67 fclose(f); 68 } 69 70 int main(int argc, char **argv) 71 { 72 if (argc < 3) 73 ERR_OUT("usage: %s <file.zst> <out_path> [dictionary] \n", argv[0]); 74 75 buffer_s const input = read_file(argv[1]); 76 77 buffer_s dict = { NULL, 0 }; 78 if (argc >= 4) { 79 dict = read_file(argv[3]); 80 } 81 82 size_t out_capacity = ZSTD_get_decompressed_size(input.address, input.size); 83 if (out_capacity == (size_t)-1) { 84 out_capacity = MAX_COMPRESSION_RATIO * input.size; 85 fprintf(stderr, "WARNING: Compressed data does not contain " 86 "decompressed size, going to assume the compression " 87 "ratio is at most %d (decompressed size of at most " 88 "%u) \n", 89 MAX_COMPRESSION_RATIO, (unsigned)out_capacity); 90 } 91 if (out_capacity > MAX_OUTPUT_SIZE) 92 ERR_OUT("Required output size too large for this implementation \n"); 93 94 u8* const output = malloc(out_capacity); 95 if (!output) ERR_OUT("failed to allocate memory \n"); 96 97 dictionary_t* const parsed_dict = create_dictionary(); 98 if (dict.size) { 99 #if defined (ZDEC_NO_DICTIONARY) 100 printf("dict.size = %zu \n", dict.size); 101 ERR_OUT("no dictionary support \n"); 102 #else 103 parse_dictionary(parsed_dict, dict.address, dict.size); 104 #endif 105 } 106 size_t const decompressed_size = 107 ZSTD_decompress_with_dict(output, out_capacity, 108 input.address, input.size, 109 parsed_dict); 110 111 free_dictionary(parsed_dict); 112 113 write_file(argv[2], output, decompressed_size); 114 115 freeBuffer(input); 116 freeBuffer(dict); 117 free(output); 118 return 0; 119 } 120