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- /* example.c -- usage example of the zlib compression library
- * Copyright (C) 1995-1996 Jean-loup Gailly.
- * For conditions of distribution and use, see copyright notice in zlib.h
- */
-
- /* $Id: example.c,v 1.16 1996/05/23 17:11:28 me Exp $ */
-
- #include <stdio.h>
- #include "zlib.h"
- #include "zutil.h"
-
- #ifdef STDC
- # include <string.h>
- # include <stdlib.h>
- #else
- extern void exit OF((int));
- #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 *out, const char *in,
- Byte *uncompr, int 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));
-
- /* ===========================================================================
- * Test compress() and uncompress()
- */
- void test_compress(compr, comprLen, uncompr, uncomprLen)
- Byte *compr, *uncompr;
- uLong comprLen, uncomprLen;
- {
- int err;
- uLong len = 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");
- } else {
- printf("uncompress(): %s\n", uncompr);
- }
- }
-
- /* ===========================================================================
- * Test read/write of .gz files
- */
- void test_gzio(
- const char *out, /* output file */
- const char *in, /* input file */
- Byte *uncompr,
- int uncomprLen)
- {
- int err;
- int len = strlen(hello)+1;
- gzFile file;
-
- file = gzopen(out, "wb");
- if (file == NULL) {
- fprintf(stderr, "gzopen error\n");
- exit(1);
- }
-
- if (gzwrite(file, (const voidp)hello, (unsigned)len) != len) {
- fprintf(stderr, "gzwrite err: %s\n", gzerror(file, &err));
- }
- gzclose(file);
-
- file = gzopen(in, "rb");
- if (file == NULL) {
- fprintf(stderr, "gzopen error\n");
- }
- strcpy((char*)uncompr, "garbage");
-
- uncomprLen = gzread(file, uncompr, (unsigned)uncomprLen);
- if (uncomprLen != len) {
- fprintf(stderr, "gzread err: %s\n", gzerror(file, &err));
- }
- gzclose(file);
-
- if (strcmp((char*)uncompr, hello)) {
- fprintf(stderr, "bad gzread\n");
- } else {
- printf("gzread(): %s\n", uncompr);
- }
- }
-
- /* ===========================================================================
- * Test deflate() with small buffers
- */
- void test_deflate(compr, comprLen)
- Byte *compr;
- uLong comprLen;
- {
- z_stream c_stream; /* compression stream */
- int err;
- int len = strlen(hello)+1;
-
- c_stream.zalloc = zcalloc;
- c_stream.zfree = zcfree;
- 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 != (uLong)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 = zcalloc;
- d_stream.zfree = zcfree;
- d_stream.opaque = (voidpf)0;
-
- err = inflateInit(&d_stream);
- CHECK_ERR(err, "inflateInit");
-
- d_stream.next_in = compr;
- d_stream.next_out = uncompr;
-
- 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");
- } else {
- printf("inflate(): %s\n", 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 = zcalloc;
- c_stream.zfree = zcfree;
- 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");
- }
-
- /* 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");
- }
- 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 = zcalloc;
- d_stream.zfree = zcfree;
- d_stream.opaque = (voidpf)0;
-
- err = inflateInit(&d_stream);
- CHECK_ERR(err, "inflateInit");
-
- d_stream.next_in = compr;
- d_stream.avail_in = (uInt)comprLen;
-
- 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);
- } 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;
- int len = strlen(hello)+1;
-
- c_stream.zalloc = zcalloc;
- c_stream.zfree = zcfree;
- 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");
- }
-
- /* ===========================================================================
- * 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 = zcalloc;
- d_stream.zfree = zcfree;
- d_stream.opaque = (voidpf)0;
-
- err = inflateInit(&d_stream);
- CHECK_ERR(err, "inflateInit");
-
- d_stream.next_in = compr;
- d_stream.next_out = uncompr;
- d_stream.avail_in = 2; /* just read the zlib header */
- 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 */
- }
- err = inflateEnd(&d_stream);
- CHECK_ERR(err, "inflateEnd");
-
- printf("after inflateSync(): hel%s\n", 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 = zcalloc;
- c_stream.zfree = zcfree;
- 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");
- }
- 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 = zcalloc;
- d_stream.zfree = zcfree;
- d_stream.opaque = (voidpf)0;
-
- err = inflateInit(&d_stream);
- CHECK_ERR(err, "inflateInit");
-
- d_stream.next_in = compr;
- d_stream.avail_in = (uInt)comprLen;
-
- 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");
- } else {
- printf("inflate with dictionary: %s\n", uncompr);
- }
- }
-
- /* ===========================================================================
- * Usage: example [output.gz [input.gz]]
- */
-
- int main(int argc, char *argv[])
- {
- Byte *compr, *uncompr;
- uLong comprLen = 10000*sizeof(int); /* don't overflow on MSDOS */
- uLong uncomprLen = comprLen;
-
- if (zlibVersion()[0] != ZLIB_VERSION[0]) {
- fprintf(stderr, "incompatible zlib version\n");
- exit(1);
-
- } else if (strcmp(zlibVersion(), ZLIB_VERSION) != 0) {
- fprintf(stderr, "warning: different zlib version\n");
- }
-
- 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] : "foo.gz"),
- (argc > 2 ? argv[2] : "foo.gz"),
- uncompr, (int)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);
-
- test_dict_deflate(compr, comprLen);
- test_dict_inflate(compr, comprLen, uncompr, uncomprLen);
-
- exit(0);
- return 0; /* to avoid warning */
- }
-