/* example.c -- usage example of the zlib compression library * Copyright (C) 1995-2003 Jean-loup Gailly. * For conditions of distribution and use, see copyright notice in zlib.h *//* @(#) $Id$ */#include <stdio.h>#include "zlib.h"#ifdef STDC#  include <string.h>#  include <stdlib.h>#else   extern void exit  OF((int));#endif#if defined(VMS) || defined(RISCOS)#  define TESTFILE "foo-gz"#else#  define TESTFILE "foo.gz"#endif#define CHECK_ERR(err, msg) { \    if (err != Z_OK) { \        fprintf(stderr, "%s error: %d\n", msg, err); \        exit(1); \    } \}const char hello[] = "hello, hello!";/* "hello world" would be more standard, but the repeated "hello" * stresses the compression code better, sorry... */const char dictionary[] = "hello";uLong dictId; /* Adler32 value of the dictionary */void test_compress      OF((Byte *compr, uLong comprLen,                            Byte *uncompr, uLong uncomprLen));void test_gzio          OF((const char *fname,                            Byte *uncompr, uLong uncomprLen));void test_deflate       OF((Byte *compr, uLong comprLen));void test_inflate       OF((Byte *compr, uLong comprLen,                            Byte *uncompr, uLong uncomprLen));void test_large_deflate OF((Byte *compr, uLong comprLen,                            Byte *uncompr, uLong uncomprLen));void test_large_inflate OF((Byte *compr, uLong comprLen,                            Byte *uncompr, uLong uncomprLen));void test_flush         OF((Byte *compr, uLong *comprLen));void test_sync          OF((Byte *compr, uLong comprLen,                            Byte *uncompr, uLong uncomprLen));void test_dict_deflate  OF((Byte *compr, uLong comprLen));void test_dict_inflate  OF((Byte *compr, uLong comprLen,                            Byte *uncompr, uLong uncomprLen));int  main               OF((int argc, char *argv[]));/* =========================================================================== * Test compress() and uncompress() */void test_compress(compr, comprLen, uncompr, uncomprLen)    Byte *compr, *uncompr;    uLong comprLen, uncomprLen;{    int err;    uLong len = (uLong)strlen(hello)+1;    err = compress(compr, &comprLen, (const Bytef*)hello, len);    CHECK_ERR(err, "compress");    strcpy((char*)uncompr, "garbage");    err = uncompress(uncompr, &uncomprLen, compr, comprLen);    CHECK_ERR(err, "uncompress");    if (strcmp((char*)uncompr, hello)) {        fprintf(stderr, "bad uncompress\n");        exit(1);    } else {        printf("uncompress(): %s\n", (char *)uncompr);    }}/* =========================================================================== * Test read/write of .gz files */void test_gzio(fname, uncompr, uncomprLen)    const char *fname; /* compressed file name */    Byte *uncompr;    uLong uncomprLen;{#ifdef NO_GZCOMPRESS    fprintf(stderr, "NO_GZCOMPRESS -- gz* functions cannot compress\n");#else    int err;    int len = (int)strlen(hello)+1;    gzFile file;    z_off_t pos;    file = gzopen(fname, "wb");    if (file == NULL) {        fprintf(stderr, "gzopen error\n");        exit(1);    }    gzputc(file, 'h');    if (gzputs(file, "ello") != 4) {        fprintf(stderr, "gzputs err: %s\n", gzerror(file, &err));        exit(1);    }    if (gzprintf(file, ", %s!", "hello") != 8) {        fprintf(stderr, "gzprintf err: %s\n", gzerror(file, &err));        exit(1);    }    gzseek(file, 1L, SEEK_CUR); /* add one zero byte */    gzclose(file);    file = gzopen(fname, "rb");    if (file == NULL) {        fprintf(stderr, "gzopen error\n");        exit(1);    }    strcpy((char*)uncompr, "garbage");    if (gzread(file, uncompr, (unsigned)uncomprLen) != len) {        fprintf(stderr, "gzread err: %s\n", gzerror(file, &err));        exit(1);    }    if (strcmp((char*)uncompr, hello)) {        fprintf(stderr, "bad gzread: %s\n", (char*)uncompr);        exit(1);    } else {        printf("gzread(): %s\n", (char*)uncompr);    }    pos = gzseek(file, -8L, SEEK_CUR);    if (pos != 6 || gztell(file) != pos) {        fprintf(stderr, "gzseek error, pos=%ld, gztell=%ld\n",                (long)pos, (long)gztell(file));        exit(1);    }    if (gzgetc(file) != ' ') {        fprintf(stderr, "gzgetc error\n");        exit(1);    }    if (gzungetc(' ', file) != ' ') {        fprintf(stderr, "gzungetc error\n");        exit(1);    }    gzgets(file, (char*)uncompr, (int)uncomprLen);    if (strlen((char*)uncompr) != 7) { /* " hello!" */        fprintf(stderr, "gzgets err after gzseek: %s\n", gzerror(file, &err));        exit(1);    }    if (strcmp((char*)uncompr, hello + 6)) {        fprintf(stderr, "bad gzgets after gzseek\n");        exit(1);    } else {        printf("gzgets() after gzseek: %s\n", (char*)uncompr);    }    gzclose(file);#endif}/* =========================================================================== * Test deflate() with small buffers */void test_deflate(compr, comprLen)    Byte *compr;    uLong comprLen;{    z_stream c_stream; /* compression stream */    int err;    uLong len = (uLong)strlen(hello)+1;    c_stream.zalloc = (alloc_func)0;    c_stream.zfree = (free_func)0;    c_stream.opaque = (voidpf)0;    err = deflateInit(&c_stream, Z_DEFAULT_COMPRESSION);    CHECK_ERR(err, "deflateInit");    c_stream.next_in  = (Bytef*)hello;    c_stream.next_out = compr;    while (c_stream.total_in != len && c_stream.total_out < comprLen) {        c_stream.avail_in = c_stream.avail_out = 1; /* force small buffers */        err = deflate(&c_stream, Z_NO_FLUSH);        CHECK_ERR(err, "deflate");    }    /* Finish the stream, still forcing small buffers: */    for (;;) {        c_stream.avail_out = 1;        err = deflate(&c_stream, Z_FINISH);        if (err == Z_STREAM_END) break;        CHECK_ERR(err, "deflate");    }    err = deflateEnd(&c_stream);    CHECK_ERR(err, "deflateEnd");}/* =========================================================================== * Test inflate() with small buffers */void test_inflate(compr, comprLen, uncompr, uncomprLen)    Byte *compr, *uncompr;    uLong comprLen, uncomprLen;{    int err;    z_stream d_stream; /* decompression stream */    strcpy((char*)uncompr, "garbage");    d_stream.zalloc = (alloc_func)0;    d_stream.zfree = (free_func)0;    d_stream.opaque = (voidpf)0;    d_stream.next_in  = compr;    d_stream.avail_in = 0;    d_stream.next_out = uncompr;    err = inflateInit(&d_stream);    CHECK_ERR(err, "inflateInit");    while (d_stream.total_out < uncomprLen && d_stream.total_in < comprLen) {        d_stream.avail_in = d_stream.avail_out = 1; /* force small buffers */        err = inflate(&d_stream, Z_NO_FLUSH);        if (err == Z_STREAM_END) break;        CHECK_ERR(err, "inflate");    }    err = inflateEnd(&d_stream);    CHECK_ERR(err, "inflateEnd");    if (strcmp((char*)uncompr, hello)) {        fprintf(stderr, "bad inflate\n");        exit(1);    } else {        printf("inflate(): %s\n", (char *)uncompr);    }}/* =========================================================================== * Test deflate() with large buffers and dynamic change of compression level */void test_large_deflate(compr, comprLen, uncompr, uncomprLen)    Byte *compr, *uncompr;    uLong comprLen, uncomprLen;{    z_stream c_stream; /* compression stream */    int err;    c_stream.zalloc = (alloc_func)0;    c_stream.zfree = (free_func)0;    c_stream.opaque = (voidpf)0;    err = deflateInit(&c_stream, Z_BEST_SPEED);    CHECK_ERR(err, "deflateInit");    c_stream.next_out = compr;    c_stream.avail_out = (uInt)comprLen;    /* At this point, uncompr is still mostly zeroes, so it should compress     * very well:     */    c_stream.next_in = uncompr;    c_stream.avail_in = (uInt)uncomprLen;    err = deflate(&c_stream, Z_NO_FLUSH);    CHECK_ERR(err, "deflate");    if (c_stream.avail_in != 0) {        fprintf(stderr, "deflate not greedy\n");        exit(1);    }    /* Feed in already compressed data and switch to no compression: */    deflateParams(&c_stream, Z_NO_COMPRESSION, Z_DEFAULT_STRATEGY);    c_stream.next_in = compr;    c_stream.avail_in = (uInt)comprLen/2;    err = deflate(&c_stream, Z_NO_FLUSH);    CHECK_ERR(err, "deflate");