xref: /aosp_15_r20/external/zstd/examples/multiple_simple_compression.c (revision 01826a4963a0d8a59bc3812d29bdf0fb76416722)
1*01826a49SYabin Cui /*
2*01826a49SYabin Cui  * Copyright (c) Meta Platforms, Inc. and affiliates.
3*01826a49SYabin Cui  * All rights reserved.
4*01826a49SYabin Cui  *
5*01826a49SYabin Cui  * This source code is licensed under both the BSD-style license (found in the
6*01826a49SYabin Cui  * LICENSE file in the root directory of this source tree) and the GPLv2 (found
7*01826a49SYabin Cui  * in the COPYING file in the root directory of this source tree).
8*01826a49SYabin Cui  * You may select, at your option, one of the above-listed licenses.
9*01826a49SYabin Cui  */
10*01826a49SYabin Cui 
11*01826a49SYabin Cui #include <stdio.h>     // printf
12*01826a49SYabin Cui #include <stdlib.h>    // free
13*01826a49SYabin Cui #include <string.h>    // memcpy, strlen
14*01826a49SYabin Cui #include <zstd.h>      // presumes zstd library is installed
15*01826a49SYabin Cui #include "common.h"    // Helper functions, CHECK(), and CHECK_ZSTD()
16*01826a49SYabin Cui 
17*01826a49SYabin Cui typedef struct {
18*01826a49SYabin Cui     void* fBuffer;
19*01826a49SYabin Cui     void* cBuffer;
20*01826a49SYabin Cui     size_t fBufferSize;
21*01826a49SYabin Cui     size_t cBufferSize;
22*01826a49SYabin Cui     ZSTD_CCtx* cctx;
23*01826a49SYabin Cui } resources;
24*01826a49SYabin Cui 
25*01826a49SYabin Cui /*
26*01826a49SYabin Cui  * allocate memory for buffers big enough to compress all files
27*01826a49SYabin Cui  * as well as memory for output file name (ofn)
28*01826a49SYabin Cui  */
createResources_orDie(int argc,const char ** argv,char ** ofn,size_t * ofnBufferLen)29*01826a49SYabin Cui static resources createResources_orDie(int argc, const char** argv, char **ofn, size_t* ofnBufferLen)
30*01826a49SYabin Cui {
31*01826a49SYabin Cui     size_t maxFilenameLength=0;
32*01826a49SYabin Cui     size_t maxFileSize = 0;
33*01826a49SYabin Cui 
34*01826a49SYabin Cui     int argNb;
35*01826a49SYabin Cui     for (argNb = 1; argNb < argc; argNb++) {
36*01826a49SYabin Cui       const char* const filename = argv[argNb];
37*01826a49SYabin Cui       size_t const filenameLength = strlen(filename);
38*01826a49SYabin Cui       size_t const fileSize = fsize_orDie(filename);
39*01826a49SYabin Cui 
40*01826a49SYabin Cui       if (filenameLength > maxFilenameLength) maxFilenameLength = filenameLength;
41*01826a49SYabin Cui       if (fileSize > maxFileSize) maxFileSize = fileSize;
42*01826a49SYabin Cui     }
43*01826a49SYabin Cui 
44*01826a49SYabin Cui     resources ress;
45*01826a49SYabin Cui     ress.fBufferSize = maxFileSize;
46*01826a49SYabin Cui     ress.cBufferSize = ZSTD_compressBound(maxFileSize);
47*01826a49SYabin Cui 
48*01826a49SYabin Cui     *ofnBufferLen = maxFilenameLength + 5;
49*01826a49SYabin Cui     *ofn = (char*)malloc_orDie(*ofnBufferLen);
50*01826a49SYabin Cui     ress.fBuffer = malloc_orDie(ress.fBufferSize);
51*01826a49SYabin Cui     ress.cBuffer = malloc_orDie(ress.cBufferSize);
52*01826a49SYabin Cui     ress.cctx = ZSTD_createCCtx();
53*01826a49SYabin Cui     CHECK(ress.cctx != NULL, "ZSTD_createCCtx() failed!");
54*01826a49SYabin Cui     return ress;
55*01826a49SYabin Cui }
56*01826a49SYabin Cui 
freeResources(resources ress,char * outFilename)57*01826a49SYabin Cui static void freeResources(resources ress, char *outFilename)
58*01826a49SYabin Cui {
59*01826a49SYabin Cui     free(ress.fBuffer);
60*01826a49SYabin Cui     free(ress.cBuffer);
61*01826a49SYabin Cui     ZSTD_freeCCtx(ress.cctx);   /* never fails */
62*01826a49SYabin Cui     free(outFilename);
63*01826a49SYabin Cui }
64*01826a49SYabin Cui 
65*01826a49SYabin Cui /* compress with pre-allocated context (ZSTD_CCtx) and input/output buffers*/
compressFile_orDie(resources ress,const char * fname,const char * oname)66*01826a49SYabin Cui static void compressFile_orDie(resources ress, const char* fname, const char* oname)
67*01826a49SYabin Cui {
68*01826a49SYabin Cui     size_t fSize = loadFile_orDie(fname, ress.fBuffer, ress.fBufferSize);
69*01826a49SYabin Cui 
70*01826a49SYabin Cui     /* Compress using the context.
71*01826a49SYabin Cui      * If you need more control over parameters, use the advanced API:
72*01826a49SYabin Cui      * ZSTD_CCtx_setParameter(), and ZSTD_compress2().
73*01826a49SYabin Cui      */
74*01826a49SYabin Cui     size_t const cSize = ZSTD_compressCCtx(ress.cctx, ress.cBuffer, ress.cBufferSize, ress.fBuffer, fSize, 1);
75*01826a49SYabin Cui     CHECK_ZSTD(cSize);
76*01826a49SYabin Cui 
77*01826a49SYabin Cui     saveFile_orDie(oname, ress.cBuffer, cSize);
78*01826a49SYabin Cui 
79*01826a49SYabin Cui     /* success */
80*01826a49SYabin Cui     printf("%25s : %6u -> %7u - %s \n", fname, (unsigned)fSize, (unsigned)cSize, oname);
81*01826a49SYabin Cui }
82*01826a49SYabin Cui 
main(int argc,const char ** argv)83*01826a49SYabin Cui int main(int argc, const char** argv)
84*01826a49SYabin Cui {
85*01826a49SYabin Cui     const char* const exeName = argv[0];
86*01826a49SYabin Cui 
87*01826a49SYabin Cui     if (argc<2) {
88*01826a49SYabin Cui         printf("wrong arguments\n");
89*01826a49SYabin Cui         printf("usage:\n");
90*01826a49SYabin Cui         printf("%s FILE(s)\n", exeName);
91*01826a49SYabin Cui         return 1;
92*01826a49SYabin Cui     }
93*01826a49SYabin Cui 
94*01826a49SYabin Cui     /* memory allocation for outFilename and resources */
95*01826a49SYabin Cui     char* outFilename;
96*01826a49SYabin Cui     size_t outFilenameBufferLen;
97*01826a49SYabin Cui     resources const ress = createResources_orDie(argc, argv, &outFilename, &outFilenameBufferLen);
98*01826a49SYabin Cui 
99*01826a49SYabin Cui     /* compress files with shared context, input and output buffers */
100*01826a49SYabin Cui     int argNb;
101*01826a49SYabin Cui     for (argNb = 1; argNb < argc; argNb++) {
102*01826a49SYabin Cui         const char* const inFilename = argv[argNb];
103*01826a49SYabin Cui         size_t const inFilenameLen = strlen(inFilename);
104*01826a49SYabin Cui         CHECK(inFilenameLen + 5 <= outFilenameBufferLen, "File name too long!");
105*01826a49SYabin Cui         memcpy(outFilename, inFilename, inFilenameLen);
106*01826a49SYabin Cui         memcpy(outFilename+inFilenameLen, ".zst", 5);
107*01826a49SYabin Cui         compressFile_orDie(ress, inFilename, outFilename);
108*01826a49SYabin Cui     }
109*01826a49SYabin Cui 
110*01826a49SYabin Cui     /* free memory */
111*01826a49SYabin Cui     freeResources(ress,outFilename);
112*01826a49SYabin Cui 
113*01826a49SYabin Cui     printf("compressed %i files \n", argc-1);
114*01826a49SYabin Cui 
115*01826a49SYabin Cui     return 0;
116*01826a49SYabin Cui }
117