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source: vbox/trunk/src/libs/zlib-1.2.1/example.c@ 7692

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export libpng and zlib so Windows and OS/2 builds cleanly.
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1/* example.c -- usage example of the zlib compression library
2 * Copyright (C) 1995-2003 Jean-loup Gailly.
3 * For conditions of distribution and use, see copyright notice in zlib.h
4 */
5
6/* @(#) $Id: example.c,v 1.1 2004/11/15 16:42:25 bird Exp $ */
7
8#include <stdio.h>
9#include "zlib.h"
10
11#ifdef STDC
12# include <string.h>
13# include <stdlib.h>
14#else
15 extern void exit OF((int));
16#endif
17
18#if defined(VMS) || defined(RISCOS)
19# define TESTFILE "foo-gz"
20#else
21# define TESTFILE "foo.gz"
22#endif
23
24#define CHECK_ERR(err, msg) { \
25 if (err != Z_OK) { \
26 fprintf(stderr, "%s error: %d\n", msg, err); \
27 exit(1); \
28 } \
29}
30
31const char hello[] = "hello, hello!";
32/* "hello world" would be more standard, but the repeated "hello"
33 * stresses the compression code better, sorry...
34 */
35
36const char dictionary[] = "hello";
37uLong dictId; /* Adler32 value of the dictionary */
38
39void test_compress OF((Byte *compr, uLong comprLen,
40 Byte *uncompr, uLong uncomprLen));
41void test_gzio OF((const char *fname,
42 Byte *uncompr, uLong uncomprLen));
43void test_deflate OF((Byte *compr, uLong comprLen));
44void test_inflate OF((Byte *compr, uLong comprLen,
45 Byte *uncompr, uLong uncomprLen));
46void test_large_deflate OF((Byte *compr, uLong comprLen,
47 Byte *uncompr, uLong uncomprLen));
48void test_large_inflate OF((Byte *compr, uLong comprLen,
49 Byte *uncompr, uLong uncomprLen));
50void test_flush OF((Byte *compr, uLong *comprLen));
51void test_sync OF((Byte *compr, uLong comprLen,
52 Byte *uncompr, uLong uncomprLen));
53void test_dict_deflate OF((Byte *compr, uLong comprLen));
54void test_dict_inflate OF((Byte *compr, uLong comprLen,
55 Byte *uncompr, uLong uncomprLen));
56int main OF((int argc, char *argv[]));
57
58/* ===========================================================================
59 * Test compress() and uncompress()
60 */
61void test_compress(compr, comprLen, uncompr, uncomprLen)
62 Byte *compr, *uncompr;
63 uLong comprLen, uncomprLen;
64{
65 int err;
66 uLong len = (uLong)strlen(hello)+1;
67
68 err = compress(compr, &comprLen, (const Bytef*)hello, len);
69 CHECK_ERR(err, "compress");
70
71 strcpy((char*)uncompr, "garbage");
72
73 err = uncompress(uncompr, &uncomprLen, compr, comprLen);
74 CHECK_ERR(err, "uncompress");
75
76 if (strcmp((char*)uncompr, hello)) {
77 fprintf(stderr, "bad uncompress\n");
78 exit(1);
79 } else {
80 printf("uncompress(): %s\n", (char *)uncompr);
81 }
82}
83
84/* ===========================================================================
85 * Test read/write of .gz files
86 */
87void test_gzio(fname, uncompr, uncomprLen)
88 const char *fname; /* compressed file name */
89 Byte *uncompr;
90 uLong uncomprLen;
91{
92#ifdef NO_GZCOMPRESS
93 fprintf(stderr, "NO_GZCOMPRESS -- gz* functions cannot compress\n");
94#else
95 int err;
96 int len = (int)strlen(hello)+1;
97 gzFile file;
98 z_off_t pos;
99
100 file = gzopen(fname, "wb");
101 if (file == NULL) {
102 fprintf(stderr, "gzopen error\n");
103 exit(1);
104 }
105 gzputc(file, 'h');
106 if (gzputs(file, "ello") != 4) {
107 fprintf(stderr, "gzputs err: %s\n", gzerror(file, &err));
108 exit(1);
109 }
110 if (gzprintf(file, ", %s!", "hello") != 8) {
111 fprintf(stderr, "gzprintf err: %s\n", gzerror(file, &err));
112 exit(1);
113 }
114 gzseek(file, 1L, SEEK_CUR); /* add one zero byte */
115 gzclose(file);
116
117 file = gzopen(fname, "rb");
118 if (file == NULL) {
119 fprintf(stderr, "gzopen error\n");
120 exit(1);
121 }
122 strcpy((char*)uncompr, "garbage");
123
124 if (gzread(file, uncompr, (unsigned)uncomprLen) != len) {
125 fprintf(stderr, "gzread err: %s\n", gzerror(file, &err));
126 exit(1);
127 }
128 if (strcmp((char*)uncompr, hello)) {
129 fprintf(stderr, "bad gzread: %s\n", (char*)uncompr);
130 exit(1);
131 } else {
132 printf("gzread(): %s\n", (char*)uncompr);
133 }
134
135 pos = gzseek(file, -8L, SEEK_CUR);
136 if (pos != 6 || gztell(file) != pos) {
137 fprintf(stderr, "gzseek error, pos=%ld, gztell=%ld\n",
138 (long)pos, (long)gztell(file));
139 exit(1);
140 }
141
142 if (gzgetc(file) != ' ') {
143 fprintf(stderr, "gzgetc error\n");
144 exit(1);
145 }
146
147 if (gzungetc(' ', file) != ' ') {
148 fprintf(stderr, "gzungetc error\n");
149 exit(1);
150 }
151
152 gzgets(file, (char*)uncompr, (int)uncomprLen);
153 if (strlen((char*)uncompr) != 7) { /* " hello!" */
154 fprintf(stderr, "gzgets err after gzseek: %s\n", gzerror(file, &err));
155 exit(1);
156 }
157 if (strcmp((char*)uncompr, hello + 6)) {
158 fprintf(stderr, "bad gzgets after gzseek\n");
159 exit(1);
160 } else {
161 printf("gzgets() after gzseek: %s\n", (char*)uncompr);
162 }
163
164 gzclose(file);
165#endif
166}
167
168/* ===========================================================================
169 * Test deflate() with small buffers
170 */
171void test_deflate(compr, comprLen)
172 Byte *compr;
173 uLong comprLen;
174{
175 z_stream c_stream; /* compression stream */
176 int err;
177 uLong len = (uLong)strlen(hello)+1;
178
179 c_stream.zalloc = (alloc_func)0;
180 c_stream.zfree = (free_func)0;
181 c_stream.opaque = (voidpf)0;
182
183 err = deflateInit(&c_stream, Z_DEFAULT_COMPRESSION);
184 CHECK_ERR(err, "deflateInit");
185
186 c_stream.next_in = (Bytef*)hello;
187 c_stream.next_out = compr;
188
189 while (c_stream.total_in != len && c_stream.total_out < comprLen) {
190 c_stream.avail_in = c_stream.avail_out = 1; /* force small buffers */
191 err = deflate(&c_stream, Z_NO_FLUSH);
192 CHECK_ERR(err, "deflate");
193 }
194 /* Finish the stream, still forcing small buffers: */
195 for (;;) {
196 c_stream.avail_out = 1;
197 err = deflate(&c_stream, Z_FINISH);
198 if (err == Z_STREAM_END) break;
199 CHECK_ERR(err, "deflate");
200 }
201
202 err = deflateEnd(&c_stream);
203 CHECK_ERR(err, "deflateEnd");
204}
205
206/* ===========================================================================
207 * Test inflate() with small buffers
208 */
209void test_inflate(compr, comprLen, uncompr, uncomprLen)
210 Byte *compr, *uncompr;
211 uLong comprLen, uncomprLen;
212{
213 int err;
214 z_stream d_stream; /* decompression stream */
215
216 strcpy((char*)uncompr, "garbage");
217
218 d_stream.zalloc = (alloc_func)0;
219 d_stream.zfree = (free_func)0;
220 d_stream.opaque = (voidpf)0;
221
222 d_stream.next_in = compr;
223 d_stream.avail_in = 0;
224 d_stream.next_out = uncompr;
225
226 err = inflateInit(&d_stream);
227 CHECK_ERR(err, "inflateInit");
228
229 while (d_stream.total_out < uncomprLen && d_stream.total_in < comprLen) {
230 d_stream.avail_in = d_stream.avail_out = 1; /* force small buffers */
231 err = inflate(&d_stream, Z_NO_FLUSH);
232 if (err == Z_STREAM_END) break;
233 CHECK_ERR(err, "inflate");
234 }
235
236 err = inflateEnd(&d_stream);
237 CHECK_ERR(err, "inflateEnd");
238
239 if (strcmp((char*)uncompr, hello)) {
240 fprintf(stderr, "bad inflate\n");
241 exit(1);
242 } else {
243 printf("inflate(): %s\n", (char *)uncompr);
244 }
245}
246
247/* ===========================================================================
248 * Test deflate() with large buffers and dynamic change of compression level
249 */
250void test_large_deflate(compr, comprLen, uncompr, uncomprLen)
251 Byte *compr, *uncompr;
252 uLong comprLen, uncomprLen;
253{
254 z_stream c_stream; /* compression stream */
255 int err;
256
257 c_stream.zalloc = (alloc_func)0;
258 c_stream.zfree = (free_func)0;
259 c_stream.opaque = (voidpf)0;
260
261 err = deflateInit(&c_stream, Z_BEST_SPEED);
262 CHECK_ERR(err, "deflateInit");
263
264 c_stream.next_out = compr;
265 c_stream.avail_out = (uInt)comprLen;
266
267 /* At this point, uncompr is still mostly zeroes, so it should compress
268 * very well:
269 */
270 c_stream.next_in = uncompr;
271 c_stream.avail_in = (uInt)uncomprLen;
272 err = deflate(&c_stream, Z_NO_FLUSH);
273 CHECK_ERR(err, "deflate");
274 if (c_stream.avail_in != 0) {
275 fprintf(stderr, "deflate not greedy\n");
276 exit(1);
277 }
278
279 /* Feed in already compressed data and switch to no compression: */
280 deflateParams(&c_stream, Z_NO_COMPRESSION, Z_DEFAULT_STRATEGY);
281 c_stream.next_in = compr;
282 c_stream.avail_in = (uInt)comprLen/2;
283 err = deflate(&c_stream, Z_NO_FLUSH);
284 CHECK_ERR(err, "deflate");
285
286 /* Switch back to compressing mode: */
287 deflateParams(&c_stream, Z_BEST_COMPRESSION, Z_FILTERED);
288 c_stream.next_in = uncompr;
289 c_stream.avail_in = (uInt)uncomprLen;
290 err = deflate(&c_stream, Z_NO_FLUSH);
291 CHECK_ERR(err, "deflate");
292
293 err = deflate(&c_stream, Z_FINISH);
294 if (err != Z_STREAM_END) {
295 fprintf(stderr, "deflate should report Z_STREAM_END\n");
296 exit(1);
297 }
298 err = deflateEnd(&c_stream);
299 CHECK_ERR(err, "deflateEnd");
300}
301
302/* ===========================================================================
303 * Test inflate() with large buffers
304 */
305void test_large_inflate(compr, comprLen, uncompr, uncomprLen)
306 Byte *compr, *uncompr;
307 uLong comprLen, uncomprLen;
308{
309 int err;
310 z_stream d_stream; /* decompression stream */
311
312 strcpy((char*)uncompr, "garbage");
313
314 d_stream.zalloc = (alloc_func)0;
315 d_stream.zfree = (free_func)0;
316 d_stream.opaque = (voidpf)0;
317
318 d_stream.next_in = compr;
319 d_stream.avail_in = (uInt)comprLen;
320
321 err = inflateInit(&d_stream);
322 CHECK_ERR(err, "inflateInit");
323
324 for (;;) {
325 d_stream.next_out = uncompr; /* discard the output */
326 d_stream.avail_out = (uInt)uncomprLen;
327 err = inflate(&d_stream, Z_NO_FLUSH);
328 if (err == Z_STREAM_END) break;
329 CHECK_ERR(err, "large inflate");
330 }
331
332 err = inflateEnd(&d_stream);
333 CHECK_ERR(err, "inflateEnd");
334
335 if (d_stream.total_out != 2*uncomprLen + comprLen/2) {
336 fprintf(stderr, "bad large inflate: %ld\n", d_stream.total_out);
337 exit(1);
338 } else {
339 printf("large_inflate(): OK\n");
340 }
341}
342
343/* ===========================================================================
344 * Test deflate() with full flush
345 */
346void test_flush(compr, comprLen)
347 Byte *compr;
348 uLong *comprLen;
349{
350 z_stream c_stream; /* compression stream */
351 int err;
352 uInt len = (uInt)strlen(hello)+1;
353
354 c_stream.zalloc = (alloc_func)0;
355 c_stream.zfree = (free_func)0;
356 c_stream.opaque = (voidpf)0;
357
358 err = deflateInit(&c_stream, Z_DEFAULT_COMPRESSION);
359 CHECK_ERR(err, "deflateInit");
360
361 c_stream.next_in = (Bytef*)hello;
362 c_stream.next_out = compr;
363 c_stream.avail_in = 3;
364 c_stream.avail_out = (uInt)*comprLen;
365 err = deflate(&c_stream, Z_FULL_FLUSH);
366 CHECK_ERR(err, "deflate");
367
368 compr[3]++; /* force an error in first compressed block */
369 c_stream.avail_in = len - 3;
370
371 err = deflate(&c_stream, Z_FINISH);
372 if (err != Z_STREAM_END) {
373 CHECK_ERR(err, "deflate");
374 }
375 err = deflateEnd(&c_stream);
376 CHECK_ERR(err, "deflateEnd");
377
378 *comprLen = c_stream.total_out;
379}
380
381/* ===========================================================================
382 * Test inflateSync()
383 */
384void test_sync(compr, comprLen, uncompr, uncomprLen)
385 Byte *compr, *uncompr;
386 uLong comprLen, uncomprLen;
387{
388 int err;
389 z_stream d_stream; /* decompression stream */
390
391 strcpy((char*)uncompr, "garbage");
392
393 d_stream.zalloc = (alloc_func)0;
394 d_stream.zfree = (free_func)0;
395 d_stream.opaque = (voidpf)0;
396
397 d_stream.next_in = compr;
398 d_stream.avail_in = 2; /* just read the zlib header */
399
400 err = inflateInit(&d_stream);
401 CHECK_ERR(err, "inflateInit");
402
403 d_stream.next_out = uncompr;
404 d_stream.avail_out = (uInt)uncomprLen;
405
406 inflate(&d_stream, Z_NO_FLUSH);
407 CHECK_ERR(err, "inflate");
408
409 d_stream.avail_in = (uInt)comprLen-2; /* read all compressed data */
410 err = inflateSync(&d_stream); /* but skip the damaged part */
411 CHECK_ERR(err, "inflateSync");
412
413 err = inflate(&d_stream, Z_FINISH);
414 if (err != Z_DATA_ERROR) {
415 fprintf(stderr, "inflate should report DATA_ERROR\n");
416 /* Because of incorrect adler32 */
417 exit(1);
418 }
419 err = inflateEnd(&d_stream);
420 CHECK_ERR(err, "inflateEnd");
421
422 printf("after inflateSync(): hel%s\n", (char *)uncompr);
423}
424
425/* ===========================================================================
426 * Test deflate() with preset dictionary
427 */
428void test_dict_deflate(compr, comprLen)
429 Byte *compr;
430 uLong comprLen;
431{
432 z_stream c_stream; /* compression stream */
433 int err;
434
435 c_stream.zalloc = (alloc_func)0;
436 c_stream.zfree = (free_func)0;
437 c_stream.opaque = (voidpf)0;
438
439 err = deflateInit(&c_stream, Z_BEST_COMPRESSION);
440 CHECK_ERR(err, "deflateInit");
441
442 err = deflateSetDictionary(&c_stream,
443 (const Bytef*)dictionary, sizeof(dictionary));
444 CHECK_ERR(err, "deflateSetDictionary");
445
446 dictId = c_stream.adler;
447 c_stream.next_out = compr;
448 c_stream.avail_out = (uInt)comprLen;
449
450 c_stream.next_in = (Bytef*)hello;
451 c_stream.avail_in = (uInt)strlen(hello)+1;
452
453 err = deflate(&c_stream, Z_FINISH);
454 if (err != Z_STREAM_END) {
455 fprintf(stderr, "deflate should report Z_STREAM_END\n");
456 exit(1);
457 }
458 err = deflateEnd(&c_stream);
459 CHECK_ERR(err, "deflateEnd");
460}
461
462/* ===========================================================================
463 * Test inflate() with a preset dictionary
464 */
465void test_dict_inflate(compr, comprLen, uncompr, uncomprLen)
466 Byte *compr, *uncompr;
467 uLong comprLen, uncomprLen;
468{
469 int err;
470 z_stream d_stream; /* decompression stream */
471
472 strcpy((char*)uncompr, "garbage");
473
474 d_stream.zalloc = (alloc_func)0;
475 d_stream.zfree = (free_func)0;
476 d_stream.opaque = (voidpf)0;
477
478 d_stream.next_in = compr;
479 d_stream.avail_in = (uInt)comprLen;
480
481 err = inflateInit(&d_stream);
482 CHECK_ERR(err, "inflateInit");
483
484 d_stream.next_out = uncompr;
485 d_stream.avail_out = (uInt)uncomprLen;
486
487 for (;;) {
488 err = inflate(&d_stream, Z_NO_FLUSH);
489 if (err == Z_STREAM_END) break;
490 if (err == Z_NEED_DICT) {
491 if (d_stream.adler != dictId) {
492 fprintf(stderr, "unexpected dictionary");
493 exit(1);
494 }
495 err = inflateSetDictionary(&d_stream, (const Bytef*)dictionary,
496 sizeof(dictionary));
497 }
498 CHECK_ERR(err, "inflate with dict");
499 }
500
501 err = inflateEnd(&d_stream);
502 CHECK_ERR(err, "inflateEnd");
503
504 if (strcmp((char*)uncompr, hello)) {
505 fprintf(stderr, "bad inflate with dict\n");
506 exit(1);
507 } else {
508 printf("inflate with dictionary: %s\n", (char *)uncompr);
509 }
510}
511
512/* ===========================================================================
513 * Usage: example [output.gz [input.gz]]
514 */
515
516int main(argc, argv)
517 int argc;
518 char *argv[];
519{
520 Byte *compr, *uncompr;
521 uLong comprLen = 10000*sizeof(int); /* don't overflow on MSDOS */
522 uLong uncomprLen = comprLen;
523 static const char* myVersion = ZLIB_VERSION;
524
525 if (zlibVersion()[0] != myVersion[0]) {
526 fprintf(stderr, "incompatible zlib version\n");
527 exit(1);
528
529 } else if (strcmp(zlibVersion(), ZLIB_VERSION) != 0) {
530 fprintf(stderr, "warning: different zlib version\n");
531 }
532
533 printf("zlib version %s = 0x%04x, compile flags = 0x%lx\n",
534 ZLIB_VERSION, ZLIB_VERNUM, zlibCompileFlags());
535
536 compr = (Byte*)calloc((uInt)comprLen, 1);
537 uncompr = (Byte*)calloc((uInt)uncomprLen, 1);
538 /* compr and uncompr are cleared to avoid reading uninitialized
539 * data and to ensure that uncompr compresses well.
540 */
541 if (compr == Z_NULL || uncompr == Z_NULL) {
542 printf("out of memory\n");
543 exit(1);
544 }
545 test_compress(compr, comprLen, uncompr, uncomprLen);
546
547 test_gzio((argc > 1 ? argv[1] : TESTFILE),
548 uncompr, uncomprLen);
549
550 test_deflate(compr, comprLen);
551 test_inflate(compr, comprLen, uncompr, uncomprLen);
552
553 test_large_deflate(compr, comprLen, uncompr, uncomprLen);
554 test_large_inflate(compr, comprLen, uncompr, uncomprLen);
555
556 test_flush(compr, &comprLen);
557 test_sync(compr, comprLen, uncompr, uncomprLen);
558 comprLen = uncomprLen;
559
560 test_dict_deflate(compr, comprLen);
561 test_dict_inflate(compr, comprLen, uncompr, uncomprLen);
562
563 free(compr);
564 free(uncompr);
565
566 return 0;
567}
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