/* example.c -- usage example of the zlib compression library * Copyright (C) 1995-2006, 2011, 2016 Jean-loup Gailly * For conditions of distribution and use, see copyright notice in zlib.h */ /* @(#) $Id$ */ #include "zlib.h"#include <stdio.h> #ifdef STDC# include <string.h># include <stdlib.h>#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); \ } \} static z_const char hello[] = "hello, hello!";/* "hello world" would be more standard, but the repeated "hello" * stresses the compression code better, sorry... */ static const char dictionary[] = "hello";static uLong dictId; /* Adler32 value of the dictionary */ #ifdef Z_SOLO static void *myalloc(void *q, unsigned n, unsigned m) { (void)q; return calloc(n, m);} static void myfree(void *q, void *p) { (void)q; free(p);} static alloc_func zalloc = myalloc;static free_func zfree = myfree; #else /* !Z_SOLO */ static alloc_func zalloc = (alloc_func)0;static free_func zfree = (free_func)0; /* =========================================================================== * Test compress() and uncompress() */static void test_compress(Byte *compr, uLong comprLen, Byte *uncompr, uLong 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 */static void test_gzio(const char *fname, 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} #endif /* Z_SOLO */ /* =========================================================================== * Test deflate() with small buffers */static void test_deflate(Byte *compr, uLong comprLen) { z_stream c_stream; /* compression stream */ int err; uLong len = (uLong)strlen(hello)+1; c_stream.zalloc = zalloc; c_stream.zfree = zfree; c_stream.opaque = (voidpf)0; err = deflateInit(&c_stream, Z_DEFAULT_COMPRESSION); CHECK_ERR(err, "deflateInit"); c_stream.next_in = (z_const unsigned char *)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 */static void test_inflate(Byte *compr, uLong comprLen, Byte *uncompr, uLong uncomprLen) { int err; z_stream d_stream; /* decompression stream */ strcpy((char*)uncompr, "garbage"); d_stream.zalloc = zalloc; d_stream.zfree = zfree; 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 */static void test_large_deflate(Byte *compr, uLong comprLen, Byte *uncompr, uLong uncomprLen) { z_stream c_stream; /* compression stream */ int err; c_stream.zalloc = zalloc; c_stream.zfree = zfree; 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)uncomprLen/2; err = deflate(&c_stream, Z_NO_FLUSH); CHECK_ERR(err, "deflate"); /* Switch back to compressing mode: */ deflateParams(&c_stream, Z_BEST_COMPRESSION, Z_FILTERED); c_stream.next_in = uncompr; c_stream.avail_in = (uInt)uncomprLen; err = deflate(&c_stream, Z_NO_FLUSH); CHECK_ERR(err, "deflate"); err = deflate(&c_stream, Z_FINISH); if (err != Z_STREAM_END) { fprintf(stderr, "deflate should report Z_STREAM_END\n"); exit(1); } err = deflateEnd(&c_stream); CHECK_ERR(err, "deflateEnd");} /* =========================================================================== * Test inflate() with large buffers */static void test_large_inflate(Byte *compr, uLong comprLen, Byte *uncompr, uLong uncomprLen) { int err; z_stream d_stream; /* decompression stream */ strcpy((char*)uncompr, "garbage"); d_stream.zalloc = zalloc; d_stream.zfree = zfree; d_stream.opaque = (voidpf)0; d_stream.next_in = compr; d_stream.avail_in = (uInt)comprLen; err = inflateInit(&d_stream); CHECK_ERR(err, "inflateInit"); for (;;) { d_stream.next_out = uncompr; /* discard the output */ d_stream.avail_out = (uInt)uncomprLen; err = inflate(&d_stream, Z_NO_FLUSH); if (err == Z_STREAM_END) break; CHECK_ERR(err, "large inflate"); } err = inflateEnd(&d_stream); CHECK_ERR(err, "inflateEnd"); if (d_stream.total_out != 2*uncomprLen + uncomprLen/2) { fprintf(stderr, "bad large inflate: %ld\n", d_stream.total_out); exit(1); } else { printf("large_inflate(): OK\n"); }} /* =========================================================================== * Test deflate() with full flush */static void test_flush(Byte *compr, uLong *comprLen) { z_stream c_stream; /* compression stream */ int err; uInt len = (uInt)strlen(hello)+1; c_stream.zalloc = zalloc; c_stream.zfree = zfree; c_stream.opaque = (voidpf)0; err = deflateInit(&c_stream, Z_DEFAULT_COMPRESSION); CHECK_ERR(err, "deflateInit"); c_stream.next_in = (z_const unsigned char *)hello; c_stream.next_out = compr; c_stream.avail_in = 3; c_stream.avail_out = (uInt)*comprLen; err = deflate(&c_stream, Z_FULL_FLUSH); CHECK_ERR(err, "deflate"); compr[3]++; /* force an error in first compressed block */ c_stream.avail_in = len - 3; err = deflate(&c_stream, Z_FINISH); if (err != Z_STREAM_END) { CHECK_ERR(err, "deflate"); } err = deflateEnd(&c_stream); CHECK_ERR(err, "deflateEnd"); *comprLen = c_stream.total_out;} /* =========================================================================== * Test inflateSync() */static void test_sync(Byte *compr, uLong comprLen, Byte *uncompr, uLong uncomprLen) { int err; z_stream d_stream; /* decompression stream */ strcpy((char*)uncompr, "garbage"); d_stream.zalloc = zalloc; d_stream.zfree = zfree; d_stream.opaque = (voidpf)0; d_stream.next_in = compr; d_stream.avail_in = 2; /* just read the zlib header */ err = inflateInit(&d_stream); CHECK_ERR(err, "inflateInit"); d_stream.next_out = uncompr; d_stream.avail_out = (uInt)uncomprLen; err = inflate(&d_stream, Z_NO_FLUSH); CHECK_ERR(err, "inflate"); d_stream.avail_in = (uInt)comprLen-2; /* read all compressed data */ err = inflateSync(&d_stream); /* but skip the damaged part */ CHECK_ERR(err, "inflateSync"); err = inflate(&d_stream, Z_FINISH); if (err != Z_STREAM_END) { fprintf(stderr, "inflate should report Z_STREAM_END\n"); exit(1); } err = inflateEnd(&d_stream); CHECK_ERR(err, "inflateEnd"); printf("after inflateSync(): hel%s\n", (char *)uncompr);} /* =========================================================================== * Test deflate() with preset dictionary */static void test_dict_deflate(Byte *compr, uLong comprLen) { z_stream c_stream; /* compression stream */ int err; c_stream.zalloc = zalloc; c_stream.zfree = zfree; c_stream.opaque = (voidpf)0; err = deflateInit(&c_stream, Z_BEST_COMPRESSION); CHECK_ERR(err, "deflateInit"); err = deflateSetDictionary(&c_stream, (const Bytef*)dictionary, (int)sizeof(dictionary)); CHECK_ERR(err, "deflateSetDictionary"); dictId = c_stream.adler; c_stream.next_out = compr; c_stream.avail_out = (uInt)comprLen; c_stream.next_in = (z_const unsigned char *)hello; c_stream.avail_in = (uInt)strlen(hello)+1; err = deflate(&c_stream, Z_FINISH); if (err != Z_STREAM_END) { fprintf(stderr, "deflate should report Z_STREAM_END\n"); exit(1); } err = deflateEnd(&c_stream); CHECK_ERR(err, "deflateEnd");} /* =========================================================================== * Test inflate() with a preset dictionary */static void test_dict_inflate(Byte *compr, uLong comprLen, Byte *uncompr, uLong uncomprLen) { int err; z_stream d_stream; /* decompression stream */ strcpy((char*)uncompr, "garbage"); d_stream.zalloc = zalloc; d_stream.zfree = zfree; d_stream.opaque = (voidpf)0; d_stream.next_in = compr; d_stream.avail_in = (uInt)comprLen; err = inflateInit(&d_stream); CHECK_ERR(err, "inflateInit"); d_stream.next_out = uncompr; d_stream.avail_out = (uInt)uncomprLen; for (;;) { err = inflate(&d_stream, Z_NO_FLUSH); if (err == Z_STREAM_END) break; if (err == Z_NEED_DICT) { if (d_stream.adler != dictId) { fprintf(stderr, "unexpected dictionary"); exit(1); } err = inflateSetDictionary(&d_stream, (const Bytef*)dictionary, (int)sizeof(dictionary)); } CHECK_ERR(err, "inflate with dict"); } err = inflateEnd(&d_stream); CHECK_ERR(err, "inflateEnd"); if (strcmp((char*)uncompr, hello)) { fprintf(stderr, "bad inflate with dict\n"); exit(1); } else { printf("inflate with dictionary: %s\n", (char *)uncompr); }} /* =========================================================================== * Usage: example [output.gz [input.gz]] */ int main(int argc, char *argv[]) { Byte *compr, *uncompr; uLong uncomprLen = 20000; uLong comprLen = 3 * uncomprLen; static const char* myVersion = ZLIB_VERSION; if (zlibVersion()[0] != myVersion[0]) { fprintf(stderr, "incompatible zlib version\n"); exit(1); Lines 1–500 of 546. 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/* example.c -- usage example of the zlib compression library * Copyright (C) 1995-2006, 2011, 2016 Jean-loup Gailly * For conditions of distribution and use, see copyright notice in zlib.h */ /* @(#) $Id$ */ #include "zlib.h" #include <stdio.h> #ifdef STDC # include <string.h> # include <stdlib.h> #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); \ } \ } static z_const char hello[] = "hello, hello!"; /* "hello world" would be more standard, but the repeated "hello" * stresses the compression code better, sorry... */ static const char dictionary[] = "hello"; static uLong dictId; /* Adler32 value of the dictionary */ #ifdef Z_SOLO static void *myalloc(void *q, unsigned n, unsigned m) { (void)q; return calloc(n, m); } static void myfree(void *q, void *p) { (void)q; free(p); } static alloc_func zalloc = myalloc; static free_func zfree = myfree; #else /* !Z_SOLO */ static alloc_func zalloc = (alloc_func)0; static free_func zfree = (free_func)0; /* =========================================================================== * Test compress() and uncompress() */ static void test_compress(Byte *compr, uLong comprLen, Byte *uncompr, uLong 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 */ static void test_gzio(const char *fname, 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 } #endif /* Z_SOLO */ /* =========================================================================== * Test deflate() with small buffers */ static void test_deflate(Byte *compr, uLong comprLen) { z_stream c_stream; /* compression stream */ int err; uLong len = (uLong)strlen(hello)+1; c_stream.zalloc = zalloc; c_stream.zfree = zfree; c_stream.opaque = (voidpf)0; err = deflateInit(&c_stream, Z_DEFAULT_COMPRESSION); CHECK_ERR(err, "deflateInit"); c_stream.next_in = (z_const unsigned char *)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 */ static void test_inflate(Byte *compr, uLong comprLen, Byte *uncompr, uLong uncomprLen) { int err; z_stream d_stream; /* decompression stream */ strcpy((char*)uncompr, "garbage"); d_stream.zalloc = zalloc; d_stream.zfree = zfree; 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 */ static void test_large_deflate(Byte *compr, uLong comprLen, Byte *uncompr, uLong uncomprLen) { z_stream c_stream; /* compression stream */ int err; c_stream.zalloc = zalloc; c_stream.zfree = zfree; 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)uncomprLen/2; err = deflate(&c_stream, Z_NO_FLUSH); CHECK_ERR(err, "deflate"); /* Switch back to compressing mode: */ deflateParams(&c_stream, Z_BEST_COMPRESSION, Z_FILTERED); c_stream.next_in = uncompr; c_stream.avail_in = (uInt)uncomprLen; err = deflate(&c_stream, Z_NO_FLUSH); CHECK_ERR(err, "deflate"); err = deflate(&c_stream, Z_FINISH); if (err != Z_STREAM_END) { fprintf(stderr, "deflate should report Z_STREAM_END\n"); exit(1); } err = deflateEnd(&c_stream); CHECK_ERR(err, "deflateEnd"); } /* =========================================================================== * Test inflate() with large buffers */ static void test_large_inflate(Byte *compr, uLong comprLen, Byte *uncompr, uLong uncomprLen) { int err; z_stream d_stream; /* decompression stream */ strcpy((char*)uncompr, "garbage"); d_stream.zalloc = zalloc; d_stream.zfree = zfree; d_stream.opaque = (voidpf)0; d_stream.next_in = compr; d_stream.avail_in = (uInt)comprLen; err = inflateInit(&d_stream); CHECK_ERR(err, "inflateInit"); for (;;) { d_stream.next_out = uncompr; /* discard the output */ d_stream.avail_out = (uInt)uncomprLen; err = inflate(&d_stream, Z_NO_FLUSH); if (err == Z_STREAM_END) break; CHECK_ERR(err, "large inflate"); } err = inflateEnd(&d_stream); CHECK_ERR(err, "inflateEnd"); if (d_stream.total_out != 2*uncomprLen + uncomprLen/2) { fprintf(stderr, "bad large inflate: %ld\n", d_stream.total_out); exit(1); } else { printf("large_inflate(): OK\n"); } } /* =========================================================================== * Test deflate() with full flush */ static void test_flush(Byte *compr, uLong *comprLen) { z_stream c_stream; /* compression stream */ int err; uInt len = (uInt)strlen(hello)+1; c_stream.zalloc = zalloc; c_stream.zfree = zfree; c_stream.opaque = (voidpf)0; err = deflateInit(&c_stream, Z_DEFAULT_COMPRESSION); CHECK_ERR(err, "deflateInit"); c_stream.next_in = (z_const unsigned char *)hello; c_stream.next_out = compr; c_stream.avail_in = 3; c_stream.avail_out = (uInt)*comprLen; err = deflate(&c_stream, Z_FULL_FLUSH); CHECK_ERR(err, "deflate"); compr[3]++; /* force an error in first compressed block */ c_stream.avail_in = len - 3; err = deflate(&c_stream, Z_FINISH); if (err != Z_STREAM_END) { CHECK_ERR(err, "deflate"); } err = deflateEnd(&c_stream); CHECK_ERR(err, "deflateEnd"); *comprLen = c_stream.total_out; } /* =========================================================================== * Test inflateSync() */ static void test_sync(Byte *compr, uLong comprLen, Byte *uncompr, uLong uncomprLen) { int err; z_stream d_stream; /* decompression stream */ strcpy((char*)uncompr, "garbage"); d_stream.zalloc = zalloc; d_stream.zfree = zfree; d_stream.opaque = (voidpf)0; d_stream.next_in = compr; d_stream.avail_in = 2; /* just read the zlib header */ err = inflateInit(&d_stream); CHECK_ERR(err, "inflateInit"); d_stream.next_out = uncompr; d_stream.avail_out = (uInt)uncomprLen; err = inflate(&d_stream, Z_NO_FLUSH); CHECK_ERR(err, "inflate"); d_stream.avail_in = (uInt)comprLen-2; /* read all compressed data */ err = inflateSync(&d_stream); /* but skip the damaged part */ CHECK_ERR(err, "inflateSync"); err = inflate(&d_stream, Z_FINISH); if (err != Z_STREAM_END) { fprintf(stderr, "inflate should report Z_STREAM_END\n"); exit(1); } err = inflateEnd(&d_stream); CHECK_ERR(err, "inflateEnd"); printf("after inflateSync(): hel%s\n", (char *)uncompr); } /* =========================================================================== * Test deflate() with preset dictionary */ static void test_dict_deflate(Byte *compr, uLong comprLen) { z_stream c_stream; /* compression stream */ int err; c_stream.zalloc = zalloc; c_stream.zfree = zfree; c_stream.opaque = (voidpf)0; err = deflateInit(&c_stream, Z_BEST_COMPRESSION); CHECK_ERR(err, "deflateInit"); err = deflateSetDictionary(&c_stream, (const Bytef*)dictionary, (int)sizeof(dictionary)); CHECK_ERR(err, "deflateSetDictionary"); dictId = c_stream.adler; c_stream.next_out = compr; c_stream.avail_out = (uInt)comprLen; c_stream.next_in = (z_const unsigned char *)hello; c_stream.avail_in = (uInt)strlen(hello)+1; err = deflate(&c_stream, Z_FINISH); if (err != Z_STREAM_END) { fprintf(stderr, "deflate should report Z_STREAM_END\n"); exit(1); } err = deflateEnd(&c_stream); CHECK_ERR(err, "deflateEnd"); } /* =========================================================================== * Test inflate() with a preset dictionary */ static void test_dict_inflate(Byte *compr, uLong comprLen, Byte *uncompr, uLong uncomprLen) { int err; z_stream d_stream; /* decompression stream */ strcpy((char*)uncompr, "garbage"); d_stream.zalloc = zalloc; d_stream.zfree = zfree; d_stream.opaque = (voidpf)0; d_stream.next_in = compr; d_stream.avail_in = (uInt)comprLen; err = inflateInit(&d_stream); CHECK_ERR(err, "inflateInit"); d_stream.next_out = uncompr; d_stream.avail_out = (uInt)uncomprLen; for (;;) { err = inflate(&d_stream, Z_NO_FLUSH); if (err == Z_STREAM_END) break; if (err == Z_NEED_DICT) { if (d_stream.adler != dictId) { fprintf(stderr, "unexpected dictionary"); exit(1); } err = inflateSetDictionary(&d_stream, (const Bytef*)dictionary, (int)sizeof(dictionary)); } CHECK_ERR(err, "inflate with dict"); } err = inflateEnd(&d_stream); CHECK_ERR(err, "inflateEnd"); if (strcmp((char*)uncompr, hello)) { fprintf(stderr, "bad inflate with dict\n"); exit(1); } else { printf("inflate with dictionary: %s\n", (char *)uncompr); } } /* =========================================================================== * Usage: example [output.gz [input.gz]] */ int main(int argc, char *argv[]) { Byte *compr, *uncompr; uLong uncomprLen = 20000; uLong comprLen = 3 * uncomprLen; static const char* myVersion = ZLIB_VERSION; if (zlibVersion()[0] != myVersion[0]) { fprintf(stderr, "incompatible zlib version\n"); exit(1);