You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
602 lines
16 KiB
602 lines
16 KiB
/* 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 */ |
|
|
|
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[])); |
|
|
|
|
|
#ifdef Z_SOLO |
|
|
|
void *myalloc OF((void *, unsigned, unsigned)); |
|
void myfree OF((void *, void *)); |
|
|
|
void *myalloc(q, n, m) |
|
void *q; |
|
unsigned n, m; |
|
{ |
|
(void)q; |
|
return calloc(n, m); |
|
} |
|
|
|
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; |
|
|
|
void test_compress OF((Byte *compr, uLong comprLen, |
|
Byte *uncompr, uLong uncomprLen)); |
|
void test_gzio OF((const char *fname, |
|
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 = (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 |
|
} |
|
|
|
#endif /* Z_SOLO */ |
|
|
|
/* =========================================================================== |
|
* 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 = 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 |
|
*/ |
|
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 = 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 |
|
*/ |
|
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 = 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)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 = 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 + 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 = 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() |
|
*/ |
|
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 = 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_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 = 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 |
|
*/ |
|
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 = 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(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); |
|
} |
|
|
|
#ifdef Z_SOLO |
|
(void)argc; |
|
(void)argv; |
|
#else |
|
test_compress(compr, comprLen, uncompr, uncomprLen); |
|
|
|
test_gzio((argc > 1 ? argv[1] : TESTFILE), |
|
uncompr, uncomprLen); |
|
#endif |
|
|
|
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; |
|
}
|
|
|