xref: /freebsd/sys/contrib/zstd/examples/streaming_compression_thread_pool.c (revision 8c784bb8cf36911b828652f0bf7e88f443abec50)
1 /*
2  * Copyright (c) Martin Liska, SUSE, 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 #include <pthread.h>
18 
19 typedef struct compress_args
20 {
21   const char *fname;
22   char *outName;
23   int cLevel;
24 #if defined(ZSTD_STATIC_LINKING_ONLY)
25   ZSTD_threadPool *pool;
26 #endif
27 } compress_args_t;
28 
29 static void *compressFile_orDie(void *data)
30 {
31     const int nbThreads = 16;
32 
33     compress_args_t *args = (compress_args_t *)data;
34     fprintf (stderr, "Starting compression of %s with level %d, using %d threads\n", args->fname, args->cLevel, nbThreads);
35     /* Open the input and output files. */
36     FILE* const fin  = fopen_orDie(args->fname, "rb");
37     FILE* const fout = fopen_orDie(args->outName, "wb");
38     /* Create the input and output buffers.
39      * They may be any size, but we recommend using these functions to size them.
40      * Performance will only suffer significantly for very tiny buffers.
41      */
42     size_t const buffInSize = ZSTD_CStreamInSize();
43     void*  const buffIn  = malloc_orDie(buffInSize);
44     size_t const buffOutSize = ZSTD_CStreamOutSize();
45     void*  const buffOut = malloc_orDie(buffOutSize);
46 
47     /* Create the context. */
48     ZSTD_CCtx* const cctx = ZSTD_createCCtx();
49     CHECK(cctx != NULL, "ZSTD_createCCtx() failed!");
50 
51 #if defined(ZSTD_STATIC_LINKING_ONLY)
52     size_t r = ZSTD_CCtx_refThreadPool(cctx, args->pool);
53     CHECK(r == 0, "ZSTD_CCtx_refThreadPool failed!");
54 #endif
55 
56     /* Set any parameters you want.
57      * Here we set the compression level, and enable the checksum.
58      */
59     CHECK_ZSTD( ZSTD_CCtx_setParameter(cctx, ZSTD_c_compressionLevel, args->cLevel) );
60     CHECK_ZSTD( ZSTD_CCtx_setParameter(cctx, ZSTD_c_checksumFlag, 1) );
61     ZSTD_CCtx_setParameter(cctx, ZSTD_c_nbWorkers, nbThreads);
62 
63     /* This loop reads from the input file, compresses that entire chunk,
64      * and writes all output produced to the output file.
65      */
66     size_t const toRead = buffInSize;
67     for (;;) {
68         size_t read = fread_orDie(buffIn, toRead, fin);
69         /* Select the flush mode.
70          * If the read may not be finished (read == toRead) we use
71          * ZSTD_e_continue. If this is the last chunk, we use ZSTD_e_end.
72          * Zstd optimizes the case where the first flush mode is ZSTD_e_end,
73          * since it knows it is compressing the entire source in one pass.
74          */
75         int const lastChunk = (read < toRead);
76         ZSTD_EndDirective const mode = lastChunk ? ZSTD_e_end : ZSTD_e_continue;
77         /* Set the input buffer to what we just read.
78          * We compress until the input buffer is empty, each time flushing the
79          * output.
80          */
81         ZSTD_inBuffer input = { buffIn, read, 0 };
82         int finished;
83         do {
84             /* Compress into the output buffer and write all of the output to
85              * the file so we can reuse the buffer next iteration.
86              */
87             ZSTD_outBuffer output = { buffOut, buffOutSize, 0 };
88             size_t const remaining = ZSTD_compressStream2(cctx, &output , &input, mode);
89             CHECK_ZSTD(remaining);
90             fwrite_orDie(buffOut, output.pos, fout);
91             /* If we're on the last chunk we're finished when zstd returns 0,
92              * which means its consumed all the input AND finished the frame.
93              * Otherwise, we're finished when we've consumed all the input.
94              */
95             finished = lastChunk ? (remaining == 0) : (input.pos == input.size);
96         } while (!finished);
97         CHECK(input.pos == input.size,
98               "Impossible: zstd only returns 0 when the input is completely consumed!");
99 
100         if (lastChunk) {
101             break;
102         }
103     }
104 
105     fprintf (stderr, "Finishing compression of %s\n", args->outName);
106 
107     ZSTD_freeCCtx(cctx);
108     fclose_orDie(fout);
109     fclose_orDie(fin);
110     free(buffIn);
111     free(buffOut);
112     free(args->outName);
113 
114     return NULL;
115 }
116 
117 
118 static char* createOutFilename_orDie(const char* filename)
119 {
120     size_t const inL = strlen(filename);
121     size_t const outL = inL + 5;
122     void* const outSpace = malloc_orDie(outL);
123     memset(outSpace, 0, outL);
124     strcat(outSpace, filename);
125     strcat(outSpace, ".zst");
126     return (char*)outSpace;
127 }
128 
129 int main(int argc, const char** argv)
130 {
131     const char* const exeName = argv[0];
132 
133     if (argc<=3) {
134         printf("wrong arguments\n");
135         printf("usage:\n");
136         printf("%s POOL_SIZE LEVEL FILES\n", exeName);
137         return 1;
138     }
139 
140     int pool_size = atoi (argv[1]);
141     CHECK(pool_size != 0, "can't parse POOL_SIZE!");
142 
143     int level = atoi (argv[2]);
144     CHECK(level != 0, "can't parse LEVEL!");
145 
146     argc -= 3;
147     argv += 3;
148 
149 #if defined(ZSTD_STATIC_LINKING_ONLY)
150     ZSTD_threadPool *pool = ZSTD_createThreadPool (pool_size);
151     CHECK(pool != NULL, "ZSTD_createThreadPool() failed!");
152     fprintf (stderr, "Using shared thread pool of size %d\n", pool_size);
153 #else
154     fprintf (stderr, "All threads use its own thread pool\n");
155 #endif
156 
157     pthread_t *threads = malloc_orDie(argc * sizeof(pthread_t));
158     compress_args_t *args = malloc_orDie(argc * sizeof(compress_args_t));
159 
160     for (unsigned i = 0; i < argc; i++)
161     {
162       args[i].fname = argv[i];
163       args[i].outName = createOutFilename_orDie(args[i].fname);
164       args[i].cLevel = level;
165 #if defined(ZSTD_STATIC_LINKING_ONLY)
166       args[i].pool = pool;
167 #endif
168 
169       pthread_create (&threads[i], NULL, compressFile_orDie, &args[i]);
170     }
171 
172     for (unsigned i = 0; i < argc; i++)
173       pthread_join (threads[i], NULL);
174 
175 #if defined(ZSTD_STATIC_LINKING_ONLY)
176     ZSTD_freeThreadPool (pool);
177 #endif
178 
179     return 0;
180 }
181