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/*===   Tuning parameter   ===*/
13#ifndef MAX_TESTED_LEVEL
14#define MAX_TESTED_LEVEL 12
15#endif
16
17
18/*===   Dependencies   ===*/
19#include <stdio.h>     // printf
20#define ZSTD_STATIC_LINKING_ONLY
21#include <zstd.h>      // presumes zstd library is installed
22#include "common.h"    // Helper functions, CHECK(), and CHECK_ZSTD()
23
24
25/*===   functions   ===*/
26
27/*! readU32FromChar() :
28    @return : unsigned integer value read from input in `char` format
29    allows and interprets K, KB, KiB, M, MB and MiB suffix.
30    Will also modify `*stringPtr`, advancing it to position where it stopped reading.
31    Note : function result can overflow if digit string > MAX_UINT */
32static unsigned readU32FromChar(const char** stringPtr)
33{
34    unsigned result = 0;
35    while ((**stringPtr >='0') && (**stringPtr <='9'))
36        result *= 10, result += **stringPtr - '0', (*stringPtr)++ ;
37    if ((**stringPtr=='K') || (**stringPtr=='M')) {
38        result <<= 10;
39        if (**stringPtr=='M') result <<= 10;
40        (*stringPtr)++ ;
41        if (**stringPtr=='i') (*stringPtr)++;
42        if (**stringPtr=='B') (*stringPtr)++;
43    }
44    return result;
45}
46
47
48int main(int argc, char const *argv[]) {
49
50    printf("\n Zstandard (v%s) memory usage for streaming : \n\n", ZSTD_versionString());
51
52    unsigned wLog = 0;
53    if (argc > 1) {
54        const char* valStr = argv[1];
55        wLog = readU32FromChar(&valStr);
56    }
57
58    int compressionLevel;
59    for (compressionLevel = 1; compressionLevel <= MAX_TESTED_LEVEL; compressionLevel++) {
60#define INPUT_SIZE 5
61#define COMPRESSED_SIZE 128
62        char const dataToCompress[INPUT_SIZE] = "abcde";
63        char compressedData[COMPRESSED_SIZE];
64        char decompressedData[INPUT_SIZE];
65        /* the ZSTD_CCtx_params structure is a way to save parameters and use
66         * them across multiple contexts. We use them here so we can call the
67         * function ZSTD_estimateCStreamSize_usingCCtxParams().
68         */
69        ZSTD_CCtx_params* const cctxParams = ZSTD_createCCtxParams();
70        CHECK(cctxParams != NULL, "ZSTD_createCCtxParams() failed!");
71
72        /* Set the compression level. */
73        CHECK_ZSTD( ZSTD_CCtxParams_setParameter(cctxParams, ZSTD_c_compressionLevel, compressionLevel) );
74        /* Set the window log.
75         * The value 0 means use the default window log, which is equivalent to
76         * not setting it.
77         */
78        CHECK_ZSTD( ZSTD_CCtxParams_setParameter(cctxParams, ZSTD_c_windowLog, wLog) );
79
80        /* Force the compressor to allocate the maximum memory size for a given
81         * level by not providing the pledged source size, or calling
82         * ZSTD_compressStream2() with ZSTD_e_end.
83         */
84        ZSTD_CCtx* const cctx = ZSTD_createCCtx();
85        CHECK(cctx != NULL, "ZSTD_createCCtx() failed!");
86        CHECK_ZSTD( ZSTD_CCtx_setParametersUsingCCtxParams(cctx, cctxParams) );
87        size_t compressedSize;
88        {
89            ZSTD_inBuffer inBuff = { dataToCompress, sizeof(dataToCompress), 0 };
90            ZSTD_outBuffer outBuff = { compressedData, sizeof(compressedData), 0 };
91            CHECK_ZSTD( ZSTD_compressStream(cctx, &outBuff, &inBuff) );
92            size_t const remaining = ZSTD_endStream(cctx, &outBuff);
93            CHECK_ZSTD(remaining);
94            CHECK(remaining == 0, "Frame not flushed!");
95            compressedSize = outBuff.pos;
96        }
97
98        ZSTD_DCtx* const dctx = ZSTD_createDCtx();
99        CHECK(dctx != NULL, "ZSTD_createDCtx() failed!");
100        /* Set the maximum allowed window log.
101         * The value 0 means use the default window log, which is equivalent to
102         * not setting it.
103         */
104        CHECK_ZSTD( ZSTD_DCtx_setParameter(dctx, ZSTD_d_windowLogMax, wLog) );
105        /* forces decompressor to use maximum memory size, since the
106         * decompressed size is not stored in the frame header.
107         */
108        {   ZSTD_inBuffer inBuff = { compressedData, compressedSize, 0 };
109            ZSTD_outBuffer outBuff = { decompressedData, sizeof(decompressedData), 0 };
110            size_t const remaining = ZSTD_decompressStream(dctx, &outBuff, &inBuff);
111            CHECK_ZSTD(remaining);
112            CHECK(remaining == 0, "Frame not complete!");
113            CHECK(outBuff.pos == sizeof(dataToCompress), "Bad decompression!");
114        }
115
116        size_t const cstreamSize = ZSTD_sizeof_CStream(cctx);
117        size_t const cstreamEstimatedSize = ZSTD_estimateCStreamSize_usingCCtxParams(cctxParams);
118        size_t const dstreamSize = ZSTD_sizeof_DStream(dctx);
119        size_t const dstreamEstimatedSize = ZSTD_estimateDStreamSize_fromFrame(compressedData, compressedSize);
120
121        CHECK(cstreamSize <= cstreamEstimatedSize, "Compression mem (%u) > estimated (%u)",
122                (unsigned)cstreamSize, (unsigned)cstreamEstimatedSize);
123        CHECK(dstreamSize <= dstreamEstimatedSize, "Decompression mem (%u) > estimated (%u)",
124                (unsigned)dstreamSize, (unsigned)dstreamEstimatedSize);
125
126        printf("Level %2i : Compression Mem = %5u KB (estimated : %5u KB) ; Decompression Mem = %4u KB (estimated : %5u KB)\n",
127                compressionLevel,
128                (unsigned)(cstreamSize>>10), (unsigned)(cstreamEstimatedSize>>10),
129                (unsigned)(dstreamSize>>10), (unsigned)(dstreamEstimatedSize>>10));
130
131        ZSTD_freeDCtx(dctx);
132        ZSTD_freeCCtx(cctx);
133        ZSTD_freeCCtxParams(cctxParams);
134        if (wLog) break;  /* single test */
135    }
136    return 0;
137}
138