1 /* 2 * Copyright (c) Yann Collet, 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 12 #include <stdio.h> // printf 13 #include <stdlib.h> // free 14 #include <string.h> // memset, strcat, strlen 15 #include <zstd.h> // presumes zstd library is installed 16 #include "common.h" // Helper functions, CHECK(), and CHECK_ZSTD() 17 18 static void compressFile_orDie(const char* fname, const char* outName, int cLevel, 19 int nbThreads) 20 { 21 fprintf (stderr, "Starting compression of %s with level %d, using %d threads\n", 22 fname, cLevel, nbThreads); 23 24 /* Open the input and output files. */ 25 FILE* const fin = fopen_orDie(fname, "rb"); 26 FILE* const fout = fopen_orDie(outName, "wb"); 27 /* Create the input and output buffers. 28 * They may be any size, but we recommend using these functions to size them. 29 * Performance will only suffer significantly for very tiny buffers. 30 */ 31 size_t const buffInSize = ZSTD_CStreamInSize(); 32 void* const buffIn = malloc_orDie(buffInSize); 33 size_t const buffOutSize = ZSTD_CStreamOutSize(); 34 void* const buffOut = malloc_orDie(buffOutSize); 35 36 /* Create the context. */ 37 ZSTD_CCtx* const cctx = ZSTD_createCCtx(); 38 CHECK(cctx != NULL, "ZSTD_createCCtx() failed!"); 39 40 /* Set any parameters you want. 41 * Here we set the compression level, and enable the checksum. 42 */ 43 CHECK_ZSTD( ZSTD_CCtx_setParameter(cctx, ZSTD_c_compressionLevel, cLevel) ); 44 CHECK_ZSTD( ZSTD_CCtx_setParameter(cctx, ZSTD_c_checksumFlag, 1) ); 45 ZSTD_CCtx_setParameter(cctx, ZSTD_c_nbWorkers, nbThreads); 46 47 /* This loop read from the input file, compresses that entire chunk, 48 * and writes all output produced to the output file. 49 */ 50 size_t const toRead = buffInSize; 51 for (;;) { 52 size_t read = fread_orDie(buffIn, toRead, fin); 53 /* Select the flush mode. 54 * If the read may not be finished (read == toRead) we use 55 * ZSTD_e_continue. If this is the last chunk, we use ZSTD_e_end. 56 * Zstd optimizes the case where the first flush mode is ZSTD_e_end, 57 * since it knows it is compressing the entire source in one pass. 58 */ 59 int const lastChunk = (read < toRead); 60 ZSTD_EndDirective const mode = lastChunk ? ZSTD_e_end : ZSTD_e_continue; 61 /* Set the input buffer to what we just read. 62 * We compress until the input buffer is empty, each time flushing the 63 * output. 64 */ 65 ZSTD_inBuffer input = { buffIn, read, 0 }; 66 int finished; 67 do { 68 /* Compress into the output buffer and write all of the output to 69 * the file so we can reuse the buffer next iteration. 70 */ 71 ZSTD_outBuffer output = { buffOut, buffOutSize, 0 }; 72 size_t const remaining = ZSTD_compressStream2(cctx, &output , &input, mode); 73 CHECK_ZSTD(remaining); 74 fwrite_orDie(buffOut, output.pos, fout); 75 /* If we're on the last chunk we're finished when zstd returns 0, 76 * which means its consumed all the input AND finished the frame. 77 * Otherwise, we're finished when we've consumed all the input. 78 */ 79 finished = lastChunk ? (remaining == 0) : (input.pos == input.size); 80 } while (!finished); 81 CHECK(input.pos == input.size, 82 "Impossible: zstd only returns 0 when the input is completely consumed!"); 83 84 if (lastChunk) { 85 break; 86 } 87 } 88 89 ZSTD_freeCCtx(cctx); 90 fclose_orDie(fout); 91 fclose_orDie(fin); 92 free(buffIn); 93 free(buffOut); 94 } 95 96 97 static char* createOutFilename_orDie(const char* filename) 98 { 99 size_t const inL = strlen(filename); 100 size_t const outL = inL + 5; 101 void* const outSpace = malloc_orDie(outL); 102 memset(outSpace, 0, outL); 103 strcat(outSpace, filename); 104 strcat(outSpace, ".zst"); 105 return (char*)outSpace; 106 } 107 108 int main(int argc, const char** argv) 109 { 110 const char* const exeName = argv[0]; 111 112 if (argc < 2) { 113 printf("wrong arguments\n"); 114 printf("usage:\n"); 115 printf("%s FILE [LEVEL] [THREADS]\n", exeName); 116 return 1; 117 } 118 119 int cLevel = 1; 120 int nbThreads = 4; 121 122 if (argc >= 3) { 123 cLevel = atoi (argv[2]); 124 CHECK(cLevel != 0, "can't parse LEVEL!"); 125 } 126 127 if (argc >= 4) { 128 nbThreads = atoi (argv[3]); 129 CHECK(nbThreads != 0, "can't parse THREADS!"); 130 } 131 132 const char* const inFilename = argv[1]; 133 134 char* const outFilename = createOutFilename_orDie(inFilename); 135 compressFile_orDie(inFilename, outFilename, cLevel, nbThreads); 136 137 free(outFilename); /* not strictly required, since program execution stops there, 138 * but some static analyzer may complain otherwise */ 139 return 0; 140 } 141