| /* example.c -- usage example of the zlib compression library |
| * Copyright (C) 1995-2006 Jean-loup Gailly. |
| * For conditions of distribution and use, see copyright notice in zlib.h |
| */ |
| |
| /* @(#) $Id: example.c,v 1.1.1.2 2002/03/11 21:53:23 tromey Exp $ */ |
| |
| #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); \ |
| } \ |
| } |
| |
| 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"); |
| |
| /* 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 |
| */ |
| void test_large_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 = (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 + comprLen/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 |
| */ |
| void test_flush(compr, comprLen) |
| Byte *compr; |
| uLong *comprLen; |
| { |
| z_stream c_stream; /* compression stream */ |
| int err; |
| uInt len = (uInt)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; |
| 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() |
| */ |
| void test_sync(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 = 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; |
| |
| 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_DATA_ERROR) { |
| fprintf(stderr, "inflate should report DATA_ERROR\n"); |
| /* Because of incorrect adler32 */ |
| exit(1); |
| } |
| err = inflateEnd(&d_stream); |
| CHECK_ERR(err, "inflateEnd"); |
| |
| printf("after inflateSync(): hel%s\n", (char *)uncompr); |
| } |
| |
| /* =========================================================================== |
| * Test deflate() with preset dictionary |
| */ |
| void test_dict_deflate(compr, comprLen) |
| Byte *compr; |
| uLong comprLen; |
| { |
| 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_COMPRESSION); |
| CHECK_ERR(err, "deflateInit"); |
| |
| err = deflateSetDictionary(&c_stream, |
| (const Bytef*)dictionary, 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 = (Bytef*)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 |
| */ |
| void test_dict_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 = (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, |
| 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(argc, argv) |
| int argc; |
| char *argv[]; |
| { |
| Byte *compr, *uncompr; |
| uLong comprLen = 10000*sizeof(int); /* don't overflow on MSDOS */ |
| uLong uncomprLen = comprLen; |
| static const char* myVersion = ZLIB_VERSION; |
| |
| if (zlibVersion()[0] != myVersion[0]) { |
| fprintf(stderr, "incompatible zlib version\n"); |
| exit(1); |
| |
| } else if (strcmp(zlibVersion(), ZLIB_VERSION) != 0) { |
| fprintf(stderr, "warning: different zlib version\n"); |
| } |
| |
| printf("zlib version %s = 0x%04x, compile flags = 0x%lx\n", |
| ZLIB_VERSION, ZLIB_VERNUM, zlibCompileFlags()); |
| |
| compr = (Byte*)calloc((uInt)comprLen, 1); |
| uncompr = (Byte*)calloc((uInt)uncomprLen, 1); |
| /* compr and uncompr are cleared to avoid reading uninitialized |
| * data and to ensure that uncompr compresses well. |
| */ |
| if (compr == Z_NULL || uncompr == Z_NULL) { |
| printf("out of memory\n"); |
| exit(1); |
| } |
| test_compress(compr, comprLen, uncompr, uncomprLen); |
| |
| test_gzio((argc > 1 ? argv[1] : TESTFILE), |
| uncompr, uncomprLen); |
| |
| test_deflate(compr, comprLen); |
| test_inflate(compr, comprLen, uncompr, uncomprLen); |
| |
| test_large_deflate(compr, comprLen, uncompr, uncomprLen); |
| test_large_inflate(compr, comprLen, uncompr, uncomprLen); |
| |
| test_flush(compr, &comprLen); |
| test_sync(compr, comprLen, uncompr, uncomprLen); |
| comprLen = uncomprLen; |
| |
| test_dict_deflate(compr, comprLen); |
| test_dict_inflate(compr, comprLen, uncompr, uncomprLen); |
| |
| free(compr); |
| free(uncompr); |
| |
| return 0; |
| } |
