1 /*
2 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
3 *
4 * This code is free software; you can redistribute it and/or modify it
5 * under the terms of the GNU General Public License version 2 only, as
6 * published by the Free Software Foundation. Oracle designates this
7 * particular file as subject to the "Classpath" exception as provided
8 * by Oracle in the LICENSE file that accompanied this code.
9 *
10 * This code is distributed in the hope that it will be useful, but WITHOUT
11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
13 * version 2 for more details (a copy is included in the LICENSE file that
14 * accompanied this code).
15 *
16 * You should have received a copy of the GNU General Public License version
17 * 2 along with this work; if not, write to the Free Software Foundation,
18 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
19 *
20 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
21 * or visit www.oracle.com if you need additional information or have any
22 * questions.
23 */
24
25 /* zlib.h -- interface of the 'zlib' general purpose compression library
26 version 1.2.5, April 19th, 2010
27
28 Copyright (C) 1995-2010 Jean-loup Gailly and Mark Adler
29
30 This software is provided 'as-is', without any express or implied
31 warranty. In no event will the authors be held liable for any damages
32 arising from the use of this software.
33
34 Permission is granted to anyone to use this software for any purpose,
35 including commercial applications, and to alter it and redistribute it
36 freely, subject to the following restrictions:
37
38 1. The origin of this software must not be misrepresented; you must not
39 claim that you wrote the original software. If you use this software
40 in a product, an acknowledgment in the product documentation would be
41 appreciated but is not required.
42 2. Altered source versions must be plainly marked as such, and must not be
43 misrepresented as being the original software.
44 3. This notice may not be removed or altered from any source distribution.
45
46 Jean-loup Gailly Mark Adler
47 jloup@gzip.org madler@alumni.caltech.edu
48
49
50 The data format used by the zlib library is described by RFCs (Request for
51 Comments) 1950 to 1952 in the files http://www.ietf.org/rfc/rfc1950.txt
52 (zlib format), rfc1951.txt (deflate format) and rfc1952.txt (gzip format).
53 */
54
55 #ifndef ZLIB_H
56 #define ZLIB_H
57
58 #include "zconf.h"
59
60 #ifdef __cplusplus
61 extern "C" {
62 #endif
63
64 #define ZLIB_VERSION "1.2.5"
65 #define ZLIB_VERNUM 0x1250
66 #define ZLIB_VER_MAJOR 1
67 #define ZLIB_VER_MINOR 2
68 #define ZLIB_VER_REVISION 5
69 #define ZLIB_VER_SUBREVISION 0
70
71 /*
72 The 'zlib' compression library provides in-memory compression and
73 decompression functions, including integrity checks of the uncompressed data.
74 This version of the library supports only one compression method (deflation)
75 but other algorithms will be added later and will have the same stream
76 interface.
77
78 Compression can be done in a single step if the buffers are large enough,
79 or can be done by repeated calls of the compression function. In the latter
80 case, the application must provide more input and/or consume the output
81 (providing more output space) before each call.
82
83 The compressed data format used by default by the in-memory functions is
84 the zlib format, which is a zlib wrapper documented in RFC 1950, wrapped
85 around a deflate stream, which is itself documented in RFC 1951.
86
87 The library also supports reading and writing files in gzip (.gz) format
88 with an interface similar to that of stdio using the functions that start
89 with "gz". The gzip format is different from the zlib format. gzip is a
90 gzip wrapper, documented in RFC 1952, wrapped around a deflate stream.
91
92 This library can optionally read and write gzip streams in memory as well.
93
94 The zlib format was designed to be compact and fast for use in memory
95 and on communications channels. The gzip format was designed for single-
96 file compression on file systems, has a larger header than zlib to maintain
97 directory information, and uses a different, slower check method than zlib.
98
99 The library does not install any signal handler. The decoder checks
100 the consistency of the compressed data, so the library should never crash
101 even in case of corrupted input.
102 */
103
104 typedef voidpf (*alloc_func) OF((voidpf opaque, uInt items, uInt size));
105 typedef void (*free_func) OF((voidpf opaque, voidpf address));
106
107 struct internal_state;
108
109 typedef struct z_stream_s {
110 Bytef *next_in; /* next input byte */
111 uInt avail_in; /* number of bytes available at next_in */
112 uLong total_in; /* total nb of input bytes read so far */
113
114 Bytef *next_out; /* next output byte should be put there */
115 uInt avail_out; /* remaining free space at next_out */
116 uLong total_out; /* total nb of bytes output so far */
117
118 char *msg; /* last error message, NULL if no error */
119 struct internal_state FAR *state; /* not visible by applications */
120
121 alloc_func zalloc; /* used to allocate the internal state */
122 free_func zfree; /* used to free the internal state */
123 voidpf opaque; /* private data object passed to zalloc and zfree */
124
125 int data_type; /* best guess about the data type: binary or text */
126 uLong adler; /* adler32 value of the uncompressed data */
127 uLong reserved; /* reserved for future use */
128 } z_stream;
129
130 typedef z_stream FAR *z_streamp;
131
132 /*
133 gzip header information passed to and from zlib routines. See RFC 1952
134 for more details on the meanings of these fields.
135 */
136 typedef struct gz_header_s {
137 int text; /* true if compressed data believed to be text */
138 uLong time; /* modification time */
139 int xflags; /* extra flags (not used when writing a gzip file) */
140 int os; /* operating system */
141 Bytef *extra; /* pointer to extra field or Z_NULL if none */
142 uInt extra_len; /* extra field length (valid if extra != Z_NULL) */
143 uInt extra_max; /* space at extra (only when reading header) */
144 Bytef *name; /* pointer to zero-terminated file name or Z_NULL */
145 uInt name_max; /* space at name (only when reading header) */
146 Bytef *comment; /* pointer to zero-terminated comment or Z_NULL */
147 uInt comm_max; /* space at comment (only when reading header) */
148 int hcrc; /* true if there was or will be a header crc */
149 int done; /* true when done reading gzip header (not used
150 when writing a gzip file) */
151 } gz_header;
152
153 typedef gz_header FAR *gz_headerp;
154
155 /*
156 The application must update next_in and avail_in when avail_in has dropped
157 to zero. It must update next_out and avail_out when avail_out has dropped
158 to zero. The application must initialize zalloc, zfree and opaque before
159 calling the init function. All other fields are set by the compression
160 library and must not be updated by the application.
161
162 The opaque value provided by the application will be passed as the first
163 parameter for calls of zalloc and zfree. This can be useful for custom
164 memory management. The compression library attaches no meaning to the
165 opaque value.
166
167 zalloc must return Z_NULL if there is not enough memory for the object.
168 If zlib is used in a multi-threaded application, zalloc and zfree must be
169 thread safe.
170
171 On 16-bit systems, the functions zalloc and zfree must be able to allocate
172 exactly 65536 bytes, but will not be required to allocate more than this if
173 the symbol MAXSEG_64K is defined (see zconf.h). WARNING: On MSDOS, pointers
174 returned by zalloc for objects of exactly 65536 bytes *must* have their
175 offset normalized to zero. The default allocation function provided by this
176 library ensures this (see zutil.c). To reduce memory requirements and avoid
177 any allocation of 64K objects, at the expense of compression ratio, compile
178 the library with -DMAX_WBITS=14 (see zconf.h).
179
180 The fields total_in and total_out can be used for statistics or progress
181 reports. After compression, total_in holds the total size of the
182 uncompressed data and may be saved for use in the decompressor (particularly
183 if the decompressor wants to decompress everything in a single step).
184 */
185
186 /* constants */
187
188 #define Z_NO_FLUSH 0
189 #define Z_PARTIAL_FLUSH 1
190 #define Z_SYNC_FLUSH 2
191 #define Z_FULL_FLUSH 3
192 #define Z_FINISH 4
193 #define Z_BLOCK 5
194 #define Z_TREES 6
195 /* Allowed flush values; see deflate() and inflate() below for details */
196
197 #define Z_OK 0
198 #define Z_STREAM_END 1
199 #define Z_NEED_DICT 2
200 #define Z_ERRNO (-1)
201 #define Z_STREAM_ERROR (-2)
202 #define Z_DATA_ERROR (-3)
203 #define Z_MEM_ERROR (-4)
204 #define Z_BUF_ERROR (-5)
205 #define Z_VERSION_ERROR (-6)
206 /* Return codes for the compression/decompression functions. Negative values
207 * are errors, positive values are used for special but normal events.
208 */
209
210 #define Z_NO_COMPRESSION 0
211 #define Z_BEST_SPEED 1
212 #define Z_BEST_COMPRESSION 9
213 #define Z_DEFAULT_COMPRESSION (-1)
214 /* compression levels */
215
216 #define Z_FILTERED 1
217 #define Z_HUFFMAN_ONLY 2
218 #define Z_RLE 3
219 #define Z_FIXED 4
220 #define Z_DEFAULT_STRATEGY 0
221 /* compression strategy; see deflateInit2() below for details */
222
223 #define Z_BINARY 0
224 #define Z_TEXT 1
225 #define Z_ASCII Z_TEXT /* for compatibility with 1.2.2 and earlier */
226 #define Z_UNKNOWN 2
227 /* Possible values of the data_type field (though see inflate()) */
228
229 #define Z_DEFLATED 8
230 /* The deflate compression method (the only one supported in this version) */
231
232 #define Z_NULL 0 /* for initializing zalloc, zfree, opaque */
233
234 #define zlib_version zlibVersion()
235 /* for compatibility with versions < 1.0.2 */
236
237
238 /* basic functions */
239
240 ZEXTERN const char * ZEXPORT zlibVersion OF((void));
241 /* The application can compare zlibVersion and ZLIB_VERSION for consistency.
242 If the first character differs, the library code actually used is not
243 compatible with the zlib.h header file used by the application. This check
244 is automatically made by deflateInit and inflateInit.
245 */
246
247 /*
248 ZEXTERN int ZEXPORT deflateInit OF((z_streamp strm, int level));
249
250 Initializes the internal stream state for compression. The fields
251 zalloc, zfree and opaque must be initialized before by the caller. If
252 zalloc and zfree are set to Z_NULL, deflateInit updates them to use default
253 allocation functions.
254
255 The compression level must be Z_DEFAULT_COMPRESSION, or between 0 and 9:
256 1 gives best speed, 9 gives best compression, 0 gives no compression at all
257 (the input data is simply copied a block at a time). Z_DEFAULT_COMPRESSION
258 requests a default compromise between speed and compression (currently
259 equivalent to level 6).
260
261 deflateInit returns Z_OK if success, Z_MEM_ERROR if there was not enough
262 memory, Z_STREAM_ERROR if level is not a valid compression level, or
263 Z_VERSION_ERROR if the zlib library version (zlib_version) is incompatible
264 with the version assumed by the caller (ZLIB_VERSION). msg is set to null
265 if there is no error message. deflateInit does not perform any compression:
266 this will be done by deflate().
267 */
268
269
270 ZEXTERN int ZEXPORT deflate OF((z_streamp strm, int flush));
271 /*
272 deflate compresses as much data as possible, and stops when the input
273 buffer becomes empty or the output buffer becomes full. It may introduce
274 some output latency (reading input without producing any output) except when
275 forced to flush.
276
277 The detailed semantics are as follows. deflate performs one or both of the
278 following actions:
279
280 - Compress more input starting at next_in and update next_in and avail_in
281 accordingly. If not all input can be processed (because there is not
282 enough room in the output buffer), next_in and avail_in are updated and
283 processing will resume at this point for the next call of deflate().
284
285 - Provide more output starting at next_out and update next_out and avail_out
286 accordingly. This action is forced if the parameter flush is non zero.
287 Forcing flush frequently degrades the compression ratio, so this parameter
288 should be set only when necessary (in interactive applications). Some
289 output may be provided even if flush is not set.
290
291 Before the call of deflate(), the application should ensure that at least
292 one of the actions is possible, by providing more input and/or consuming more
293 output, and updating avail_in or avail_out accordingly; avail_out should
294 never be zero before the call. The application can consume the compressed
295 output when it wants, for example when the output buffer is full (avail_out
296 == 0), or after each call of deflate(). If deflate returns Z_OK and with
297 zero avail_out, it must be called again after making room in the output
298 buffer because there might be more output pending.
299
300 Normally the parameter flush is set to Z_NO_FLUSH, which allows deflate to
301 decide how much data to accumulate before producing output, in order to
302 maximize compression.
303
304 If the parameter flush is set to Z_SYNC_FLUSH, all pending output is
305 flushed to the output buffer and the output is aligned on a byte boundary, so
306 that the decompressor can get all input data available so far. (In
307 particular avail_in is zero after the call if enough output space has been
308 provided before the call.) Flushing may degrade compression for some
309 compression algorithms and so it should be used only when necessary. This
310 completes the current deflate block and follows it with an empty stored block
311 that is three bits plus filler bits to the next byte, followed by four bytes
312 (00 00 ff ff).
313
314 If flush is set to Z_PARTIAL_FLUSH, all pending output is flushed to the
315 output buffer, but the output is not aligned to a byte boundary. All of the
316 input data so far will be available to the decompressor, as for Z_SYNC_FLUSH.
317 This completes the current deflate block and follows it with an empty fixed
318 codes block that is 10 bits long. This assures that enough bytes are output
319 in order for the decompressor to finish the block before the empty fixed code
320 block.
321
322 If flush is set to Z_BLOCK, a deflate block is completed and emitted, as
323 for Z_SYNC_FLUSH, but the output is not aligned on a byte boundary, and up to
324 seven bits of the current block are held to be written as the next byte after
325 the next deflate block is completed. In this case, the decompressor may not
326 be provided enough bits at this point in order to complete decompression of
327 the data provided so far to the compressor. It may need to wait for the next
328 block to be emitted. This is for advanced applications that need to control
329 the emission of deflate blocks.
330
331 If flush is set to Z_FULL_FLUSH, all output is flushed as with
332 Z_SYNC_FLUSH, and the compression state is reset so that decompression can
333 restart from this point if previous compressed data has been damaged or if
334 random access is desired. Using Z_FULL_FLUSH too often can seriously degrade
335 compression.
336
337 If deflate returns with avail_out == 0, this function must be called again
338 with the same value of the flush parameter and more output space (updated
339 avail_out), until the flush is complete (deflate returns with non-zero
340 avail_out). In the case of a Z_FULL_FLUSH or Z_SYNC_FLUSH, make sure that
341 avail_out is greater than six to avoid repeated flush markers due to
342 avail_out == 0 on return.
343
344 If the parameter flush is set to Z_FINISH, pending input is processed,
345 pending output is flushed and deflate returns with Z_STREAM_END if there was
346 enough output space; if deflate returns with Z_OK, this function must be
347 called again with Z_FINISH and more output space (updated avail_out) but no
348 more input data, until it returns with Z_STREAM_END or an error. After
349 deflate has returned Z_STREAM_END, the only possible operations on the stream
350 are deflateReset or deflateEnd.
351
352 Z_FINISH can be used immediately after deflateInit if all the compression
353 is to be done in a single step. In this case, avail_out must be at least the
354 value returned by deflateBound (see below). If deflate does not return
355 Z_STREAM_END, then it must be called again as described above.
356
357 deflate() sets strm->adler to the adler32 checksum of all input read
358 so far (that is, total_in bytes).
359
360 deflate() may update strm->data_type if it can make a good guess about
361 the input data type (Z_BINARY or Z_TEXT). In doubt, the data is considered
362 binary. This field is only for information purposes and does not affect the
363 compression algorithm in any manner.
364
365 deflate() returns Z_OK if some progress has been made (more input
366 processed or more output produced), Z_STREAM_END if all input has been
367 consumed and all output has been produced (only when flush is set to
368 Z_FINISH), Z_STREAM_ERROR if the stream state was inconsistent (for example
369 if next_in or next_out was Z_NULL), Z_BUF_ERROR if no progress is possible
370 (for example avail_in or avail_out was zero). Note that Z_BUF_ERROR is not
371 fatal, and deflate() can be called again with more input and more output
372 space to continue compressing.
373 */
374
375
376 ZEXTERN int ZEXPORT deflateEnd OF((z_streamp strm));
377 /*
378 All dynamically allocated data structures for this stream are freed.
379 This function discards any unprocessed input and does not flush any pending
380 output.
381
382 deflateEnd returns Z_OK if success, Z_STREAM_ERROR if the
383 stream state was inconsistent, Z_DATA_ERROR if the stream was freed
384 prematurely (some input or output was discarded). In the error case, msg
385 may be set but then points to a static string (which must not be
386 deallocated).
387 */
388
389
390 /*
391 ZEXTERN int ZEXPORT inflateInit OF((z_streamp strm));
392
393 Initializes the internal stream state for decompression. The fields
394 next_in, avail_in, zalloc, zfree and opaque must be initialized before by
395 the caller. If next_in is not Z_NULL and avail_in is large enough (the
396 exact value depends on the compression method), inflateInit determines the
397 compression method from the zlib header and allocates all data structures
398 accordingly; otherwise the allocation will be deferred to the first call of
399 inflate. If zalloc and zfree are set to Z_NULL, inflateInit updates them to
400 use default allocation functions.
401
402 inflateInit returns Z_OK if success, Z_MEM_ERROR if there was not enough
403 memory, Z_VERSION_ERROR if the zlib library version is incompatible with the
404 version assumed by the caller, or Z_STREAM_ERROR if the parameters are
405 invalid, such as a null pointer to the structure. msg is set to null if
406 there is no error message. inflateInit does not perform any decompression
407 apart from possibly reading the zlib header if present: actual decompression
408 will be done by inflate(). (So next_in and avail_in may be modified, but
409 next_out and avail_out are unused and unchanged.) The current implementation
410 of inflateInit() does not process any header information -- that is deferred
411 until inflate() is called.
412 */
413
414
415 ZEXTERN int ZEXPORT inflate OF((z_streamp strm, int flush));
416 /*
417 inflate decompresses as much data as possible, and stops when the input
418 buffer becomes empty or the output buffer becomes full. It may introduce
419 some output latency (reading input without producing any output) except when
420 forced to flush.
421
422 The detailed semantics are as follows. inflate performs one or both of the
423 following actions:
424
425 - Decompress more input starting at next_in and update next_in and avail_in
426 accordingly. If not all input can be processed (because there is not
427 enough room in the output buffer), next_in is updated and processing will
428 resume at this point for the next call of inflate().
429
430 - Provide more output starting at next_out and update next_out and avail_out
431 accordingly. inflate() provides as much output as possible, until there is
432 no more input data or no more space in the output buffer (see below about
433 the flush parameter).
434
435 Before the call of inflate(), the application should ensure that at least
436 one of the actions is possible, by providing more input and/or consuming more
437 output, and updating the next_* and avail_* values accordingly. The
438 application can consume the uncompressed output when it wants, for example
439 when the output buffer is full (avail_out == 0), or after each call of
440 inflate(). If inflate returns Z_OK and with zero avail_out, it must be
441 called again after making room in the output buffer because there might be
442 more output pending.
443
444 The flush parameter of inflate() can be Z_NO_FLUSH, Z_SYNC_FLUSH, Z_FINISH,
445 Z_BLOCK, or Z_TREES. Z_SYNC_FLUSH requests that inflate() flush as much
446 output as possible to the output buffer. Z_BLOCK requests that inflate()
447 stop if and when it gets to the next deflate block boundary. When decoding
448 the zlib or gzip format, this will cause inflate() to return immediately
449 after the header and before the first block. When doing a raw inflate,
450 inflate() will go ahead and process the first block, and will return when it
451 gets to the end of that block, or when it runs out of data.
452
453 The Z_BLOCK option assists in appending to or combining deflate streams.
454 Also to assist in this, on return inflate() will set strm->data_type to the
455 number of unused bits in the last byte taken from strm->next_in, plus 64 if
456 inflate() is currently decoding the last block in the deflate stream, plus
457 128 if inflate() returned immediately after decoding an end-of-block code or
458 decoding the complete header up to just before the first byte of the deflate
459 stream. The end-of-block will not be indicated until all of the uncompressed
460 data from that block has been written to strm->next_out. The number of
461 unused bits may in general be greater than seven, except when bit 7 of
462 data_type is set, in which case the number of unused bits will be less than
463 eight. data_type is set as noted here every time inflate() returns for all
464 flush options, and so can be used to determine the amount of currently
465 consumed input in bits.
466
467 The Z_TREES option behaves as Z_BLOCK does, but it also returns when the
468 end of each deflate block header is reached, before any actual data in that
469 block is decoded. This allows the caller to determine the length of the
470 deflate block header for later use in random access within a deflate block.
471 256 is added to the value of strm->data_type when inflate() returns
472 immediately after reaching the end of the deflate block header.
473
474 inflate() should normally be called until it returns Z_STREAM_END or an
475 error. However if all decompression is to be performed in a single step (a
476 single call of inflate), the parameter flush should be set to Z_FINISH. In
477 this case all pending input is processed and all pending output is flushed;
478 avail_out must be large enough to hold all the uncompressed data. (The size
479 of the uncompressed data may have been saved by the compressor for this
480 purpose.) The next operation on this stream must be inflateEnd to deallocate
481 the decompression state. The use of Z_FINISH is never required, but can be
482 used to inform inflate that a faster approach may be used for the single
483 inflate() call.
484
485 In this implementation, inflate() always flushes as much output as
486 possible to the output buffer, and always uses the faster approach on the
487 first call. So the only effect of the flush parameter in this implementation
488 is on the return value of inflate(), as noted below, or when it returns early
489 because Z_BLOCK or Z_TREES is used.
490
491 If a preset dictionary is needed after this call (see inflateSetDictionary
492 below), inflate sets strm->adler to the adler32 checksum of the dictionary
493 chosen by the compressor and returns Z_NEED_DICT; otherwise it sets
494 strm->adler to the adler32 checksum of all output produced so far (that is,
495 total_out bytes) and returns Z_OK, Z_STREAM_END or an error code as described
496 below. At the end of the stream, inflate() checks that its computed adler32
497 checksum is equal to that saved by the compressor and returns Z_STREAM_END
498 only if the checksum is correct.
499
500 inflate() can decompress and check either zlib-wrapped or gzip-wrapped
501 deflate data. The header type is detected automatically, if requested when
502 initializing with inflateInit2(). Any information contained in the gzip
503 header is not retained, so applications that need that information should
504 instead use raw inflate, see inflateInit2() below, or inflateBack() and
505 perform their own processing of the gzip header and trailer.
506
507 inflate() returns Z_OK if some progress has been made (more input processed
508 or more output produced), Z_STREAM_END if the end of the compressed data has
509 been reached and all uncompressed output has been produced, Z_NEED_DICT if a
510 preset dictionary is needed at this point, Z_DATA_ERROR if the input data was
511 corrupted (input stream not conforming to the zlib format or incorrect check
512 value), Z_STREAM_ERROR if the stream structure was inconsistent (for example
513 next_in or next_out was Z_NULL), Z_MEM_ERROR if there was not enough memory,
514 Z_BUF_ERROR if no progress is possible or if there was not enough room in the
515 output buffer when Z_FINISH is used. Note that Z_BUF_ERROR is not fatal, and
516 inflate() can be called again with more input and more output space to
517 continue decompressing. If Z_DATA_ERROR is returned, the application may
518 then call inflateSync() to look for a good compression block if a partial
519 recovery of the data is desired.
520 */
521
522
523 ZEXTERN int ZEXPORT inflateEnd OF((z_streamp strm));
524 /*
525 All dynamically allocated data structures for this stream are freed.
526 This function discards any unprocessed input and does not flush any pending
527 output.
528
529 inflateEnd returns Z_OK if success, Z_STREAM_ERROR if the stream state
530 was inconsistent. In the error case, msg may be set but then points to a
531 static string (which must not be deallocated).
532 */
533
534
535 /* Advanced functions */
536
537 /*
538 The following functions are needed only in some special applications.
539 */
540
541 /*
542 ZEXTERN int ZEXPORT deflateInit2 OF((z_streamp strm,
543 int level,
544 int method,
545 int windowBits,
546 int memLevel,
547 int strategy));
548
549 This is another version of deflateInit with more compression options. The
550 fields next_in, zalloc, zfree and opaque must be initialized before by the
551 caller.
552
553 The method parameter is the compression method. It must be Z_DEFLATED in
554 this version of the library.
555
556 The windowBits parameter is the base two logarithm of the window size
557 (the size of the history buffer). It should be in the range 8..15 for this
558 version of the library. Larger values of this parameter result in better
559 compression at the expense of memory usage. The default value is 15 if
560 deflateInit is used instead.
561
562 windowBits can also be -8..-15 for raw deflate. In this case, -windowBits
563 determines the window size. deflate() will then generate raw deflate data
564 with no zlib header or trailer, and will not compute an adler32 check value.
565
566 windowBits can also be greater than 15 for optional gzip encoding. Add
567 16 to windowBits to write a simple gzip header and trailer around the
568 compressed data instead of a zlib wrapper. The gzip header will have no
569 file name, no extra data, no comment, no modification time (set to zero), no
570 header crc, and the operating system will be set to 255 (unknown). If a
571 gzip stream is being written, strm->adler is a crc32 instead of an adler32.
572
573 The memLevel parameter specifies how much memory should be allocated
574 for the internal compression state. memLevel=1 uses minimum memory but is
575 slow and reduces compression ratio; memLevel=9 uses maximum memory for
576 optimal speed. The default value is 8. See zconf.h for total memory usage
577 as a function of windowBits and memLevel.
578
579 The strategy parameter is used to tune the compression algorithm. Use the
580 value Z_DEFAULT_STRATEGY for normal data, Z_FILTERED for data produced by a
581 filter (or predictor), Z_HUFFMAN_ONLY to force Huffman encoding only (no
582 string match), or Z_RLE to limit match distances to one (run-length
583 encoding). Filtered data consists mostly of small values with a somewhat
584 random distribution. In this case, the compression algorithm is tuned to
585 compress them better. The effect of Z_FILTERED is to force more Huffman
586 coding and less string matching; it is somewhat intermediate between
587 Z_DEFAULT_STRATEGY and Z_HUFFMAN_ONLY. Z_RLE is designed to be almost as
588 fast as Z_HUFFMAN_ONLY, but give better compression for PNG image data. The
589 strategy parameter only affects the compression ratio but not the
590 correctness of the compressed output even if it is not set appropriately.
591 Z_FIXED prevents the use of dynamic Huffman codes, allowing for a simpler
592 decoder for special applications.
593
594 deflateInit2 returns Z_OK if success, Z_MEM_ERROR if there was not enough
595 memory, Z_STREAM_ERROR if any parameter is invalid (such as an invalid
596 method), or Z_VERSION_ERROR if the zlib library version (zlib_version) is
597 incompatible with the version assumed by the caller (ZLIB_VERSION). msg is
598 set to null if there is no error message. deflateInit2 does not perform any
599 compression: this will be done by deflate().
600 */
601
602 ZEXTERN int ZEXPORT deflateSetDictionary OF((z_streamp strm,
603 const Bytef *dictionary,
604 uInt dictLength));
605 /*
606 Initializes the compression dictionary from the given byte sequence
607 without producing any compressed output. This function must be called
608 immediately after deflateInit, deflateInit2 or deflateReset, before any call
609 of deflate. The compressor and decompressor must use exactly the same
610 dictionary (see inflateSetDictionary).
611
612 The dictionary should consist of strings (byte sequences) that are likely
613 to be encountered later in the data to be compressed, with the most commonly
614 used strings preferably put towards the end of the dictionary. Using a
615 dictionary is most useful when the data to be compressed is short and can be
616 predicted with good accuracy; the data can then be compressed better than
617 with the default empty dictionary.
618
619 Depending on the size of the compression data structures selected by
620 deflateInit or deflateInit2, a part of the dictionary may in effect be
621 discarded, for example if the dictionary is larger than the window size
622 provided in deflateInit or deflateInit2. Thus the strings most likely to be
623 useful should be put at the end of the dictionary, not at the front. In
624 addition, the current implementation of deflate will use at most the window
625 size minus 262 bytes of the provided dictionary.
626
627 Upon return of this function, strm->adler is set to the adler32 value
628 of the dictionary; the decompressor may later use this value to determine
629 which dictionary has been used by the compressor. (The adler32 value
630 applies to the whole dictionary even if only a subset of the dictionary is
631 actually used by the compressor.) If a raw deflate was requested, then the
632 adler32 value is not computed and strm->adler is not set.
633
634 deflateSetDictionary returns Z_OK if success, or Z_STREAM_ERROR if a
635 parameter is invalid (e.g. dictionary being Z_NULL) or the stream state is
636 inconsistent (for example if deflate has already been called for this stream
637 or if the compression method is bsort). deflateSetDictionary does not
638 perform any compression: this will be done by deflate().
639 */
640
641 ZEXTERN int ZEXPORT deflateCopy OF((z_streamp dest,
642 z_streamp source));
643 /*
644 Sets the destination stream as a complete copy of the source stream.
645
646 This function can be useful when several compression strategies will be
647 tried, for example when there are several ways of pre-processing the input
648 data with a filter. The streams that will be discarded should then be freed
649 by calling deflateEnd. Note that deflateCopy duplicates the internal
650 compression state which can be quite large, so this strategy is slow and can
651 consume lots of memory.
652
653 deflateCopy returns Z_OK if success, Z_MEM_ERROR if there was not
654 enough memory, Z_STREAM_ERROR if the source stream state was inconsistent
655 (such as zalloc being Z_NULL). msg is left unchanged in both source and
656 destination.
657 */
658
659 ZEXTERN int ZEXPORT deflateReset OF((z_streamp strm));
660 /*
661 This function is equivalent to deflateEnd followed by deflateInit,
662 but does not free and reallocate all the internal compression state. The
663 stream will keep the same compression level and any other attributes that
664 may have been set by deflateInit2.
665
666 deflateReset returns Z_OK if success, or Z_STREAM_ERROR if the source
667 stream state was inconsistent (such as zalloc or state being Z_NULL).
668 */
669
670 ZEXTERN int ZEXPORT deflateParams OF((z_streamp strm,
671 int level,
672 int strategy));
673 /*
674 Dynamically update the compression level and compression strategy. The
675 interpretation of level and strategy is as in deflateInit2. This can be
676 used to switch between compression and straight copy of the input data, or
677 to switch to a different kind of input data requiring a different strategy.
678 If the compression level is changed, the input available so far is
679 compressed with the old level (and may be flushed); the new level will take
680 effect only at the next call of deflate().
681
682 Before the call of deflateParams, the stream state must be set as for
683 a call of deflate(), since the currently available input may have to be
684 compressed and flushed. In particular, strm->avail_out must be non-zero.
685
686 deflateParams returns Z_OK if success, Z_STREAM_ERROR if the source
687 stream state was inconsistent or if a parameter was invalid, Z_BUF_ERROR if
688 strm->avail_out was zero.
689 */
690
691 ZEXTERN int ZEXPORT deflateTune OF((z_streamp strm,
692 int good_length,
693 int max_lazy,
694 int nice_length,
695 int max_chain));
696 /*
697 Fine tune deflate's internal compression parameters. This should only be
698 used by someone who understands the algorithm used by zlib's deflate for
699 searching for the best matching string, and even then only by the most
700 fanatic optimizer trying to squeeze out the last compressed bit for their
701 specific input data. Read the deflate.c source code for the meaning of the
702 max_lazy, good_length, nice_length, and max_chain parameters.
703
704 deflateTune() can be called after deflateInit() or deflateInit2(), and
705 returns Z_OK on success, or Z_STREAM_ERROR for an invalid deflate stream.
706 */
707
708 ZEXTERN uLong ZEXPORT deflateBound OF((z_streamp strm,
709 uLong sourceLen));
710 /*
711 deflateBound() returns an upper bound on the compressed size after
712 deflation of sourceLen bytes. It must be called after deflateInit() or
713 deflateInit2(), and after deflateSetHeader(), if used. This would be used
714 to allocate an output buffer for deflation in a single pass, and so would be
715 called before deflate().
716 */
717
718 ZEXTERN int ZEXPORT deflatePrime OF((z_streamp strm,
719 int bits,
720 int value));
721 /*
722 deflatePrime() inserts bits in the deflate output stream. The intent
723 is that this function is used to start off the deflate output with the bits
724 leftover from a previous deflate stream when appending to it. As such, this
725 function can only be used for raw deflate, and must be used before the first
726 deflate() call after a deflateInit2() or deflateReset(). bits must be less
727 than or equal to 16, and that many of the least significant bits of value
728 will be inserted in the output.
729
730 deflatePrime returns Z_OK if success, or Z_STREAM_ERROR if the source
731 stream state was inconsistent.
732 */
733
734 ZEXTERN int ZEXPORT deflateSetHeader OF((z_streamp strm,
735 gz_headerp head));
736 /*
737 deflateSetHeader() provides gzip header information for when a gzip
738 stream is requested by deflateInit2(). deflateSetHeader() may be called
739 after deflateInit2() or deflateReset() and before the first call of
740 deflate(). The text, time, os, extra field, name, and comment information
741 in the provided gz_header structure are written to the gzip header (xflag is
742 ignored -- the extra flags are set according to the compression level). The
743 caller must assure that, if not Z_NULL, name and comment are terminated with
744 a zero byte, and that if extra is not Z_NULL, that extra_len bytes are
745 available there. If hcrc is true, a gzip header crc is included. Note that
746 the current versions of the command-line version of gzip (up through version
747 1.3.x) do not support header crc's, and will report that it is a "multi-part
748 gzip file" and give up.
749
750 If deflateSetHeader is not used, the default gzip header has text false,
751 the time set to zero, and os set to 255, with no extra, name, or comment
752 fields. The gzip header is returned to the default state by deflateReset().
753
754 deflateSetHeader returns Z_OK if success, or Z_STREAM_ERROR if the source
755 stream state was inconsistent.
756 */
757
758 /*
759 ZEXTERN int ZEXPORT inflateInit2 OF((z_streamp strm,
760 int windowBits));
761
762 This is another version of inflateInit with an extra parameter. The
763 fields next_in, avail_in, zalloc, zfree and opaque must be initialized
764 before by the caller.
765
766 The windowBits parameter is the base two logarithm of the maximum window
767 size (the size of the history buffer). It should be in the range 8..15 for
768 this version of the library. The default value is 15 if inflateInit is used
769 instead. windowBits must be greater than or equal to the windowBits value
770 provided to deflateInit2() while compressing, or it must be equal to 15 if
771 deflateInit2() was not used. If a compressed stream with a larger window
772 size is given as input, inflate() will return with the error code
773 Z_DATA_ERROR instead of trying to allocate a larger window.
774
775 windowBits can also be zero to request that inflate use the window size in
776 the zlib header of the compressed stream.
777
778 windowBits can also be -8..-15 for raw inflate. In this case, -windowBits
779 determines the window size. inflate() will then process raw deflate data,
780 not looking for a zlib or gzip header, not generating a check value, and not
781 looking for any check values for comparison at the end of the stream. This
782 is for use with other formats that use the deflate compressed data format
783 such as zip. Those formats provide their own check values. If a custom
784 format is developed using the raw deflate format for compressed data, it is
785 recommended that a check value such as an adler32 or a crc32 be applied to
786 the uncompressed data as is done in the zlib, gzip, and zip formats. For
787 most applications, the zlib format should be used as is. Note that comments
788 above on the use in deflateInit2() applies to the magnitude of windowBits.
789
790 windowBits can also be greater than 15 for optional gzip decoding. Add
791 32 to windowBits to enable zlib and gzip decoding with automatic header
792 detection, or add 16 to decode only the gzip format (the zlib format will
793 return a Z_DATA_ERROR). If a gzip stream is being decoded, strm->adler is a
794 crc32 instead of an adler32.
795
796 inflateInit2 returns Z_OK if success, Z_MEM_ERROR if there was not enough
797 memory, Z_VERSION_ERROR if the zlib library version is incompatible with the
798 version assumed by the caller, or Z_STREAM_ERROR if the parameters are
799 invalid, such as a null pointer to the structure. msg is set to null if
800 there is no error message. inflateInit2 does not perform any decompression
801 apart from possibly reading the zlib header if present: actual decompression
802 will be done by inflate(). (So next_in and avail_in may be modified, but
803 next_out and avail_out are unused and unchanged.) The current implementation
804 of inflateInit2() does not process any header information -- that is
805 deferred until inflate() is called.
806 */
807
808 ZEXTERN int ZEXPORT inflateSetDictionary OF((z_streamp strm,
809 const Bytef *dictionary,
810 uInt dictLength));
811 /*
812 Initializes the decompression dictionary from the given uncompressed byte
813 sequence. This function must be called immediately after a call of inflate,
814 if that call returned Z_NEED_DICT. The dictionary chosen by the compressor
815 can be determined from the adler32 value returned by that call of inflate.
816 The compressor and decompressor must use exactly the same dictionary (see
817 deflateSetDictionary). For raw inflate, this function can be called
818 immediately after inflateInit2() or inflateReset() and before any call of
819 inflate() to set the dictionary. The application must insure that the
820 dictionary that was used for compression is provided.
821
822 inflateSetDictionary returns Z_OK if success, Z_STREAM_ERROR if a
823 parameter is invalid (e.g. dictionary being Z_NULL) or the stream state is
824 inconsistent, Z_DATA_ERROR if the given dictionary doesn't match the
825 expected one (incorrect adler32 value). inflateSetDictionary does not
826 perform any decompression: this will be done by subsequent calls of
827 inflate().
828 */
829
830 ZEXTERN int ZEXPORT inflateSync OF((z_streamp strm));
831 /*
832 Skips invalid compressed data until a full flush point (see above the
833 description of deflate with Z_FULL_FLUSH) can be found, or until all
834 available input is skipped. No output is provided.
835
836 inflateSync returns Z_OK if a full flush point has been found, Z_BUF_ERROR
837 if no more input was provided, Z_DATA_ERROR if no flush point has been
838 found, or Z_STREAM_ERROR if the stream structure was inconsistent. In the
839 success case, the application may save the current current value of total_in
840 which indicates where valid compressed data was found. In the error case,
841 the application may repeatedly call inflateSync, providing more input each
842 time, until success or end of the input data.
843 */
844
845 ZEXTERN int ZEXPORT inflateCopy OF((z_streamp dest,
846 z_streamp source));
847 /*
848 Sets the destination stream as a complete copy of the source stream.
849
850 This function can be useful when randomly accessing a large stream. The
851 first pass through the stream can periodically record the inflate state,
852 allowing restarting inflate at those points when randomly accessing the
853 stream.
854
855 inflateCopy returns Z_OK if success, Z_MEM_ERROR if there was not
856 enough memory, Z_STREAM_ERROR if the source stream state was inconsistent
857 (such as zalloc being Z_NULL). msg is left unchanged in both source and
858 destination.
859 */
860
861 ZEXTERN int ZEXPORT inflateReset OF((z_streamp strm));
862 /*
863 This function is equivalent to inflateEnd followed by inflateInit,
864 but does not free and reallocate all the internal decompression state. The
865 stream will keep attributes that may have been set by inflateInit2.
866
867 inflateReset returns Z_OK if success, or Z_STREAM_ERROR if the source
868 stream state was inconsistent (such as zalloc or state being Z_NULL).
869 */
870
871 ZEXTERN int ZEXPORT inflateReset2 OF((z_streamp strm,
872 int windowBits));
873 /*
874 This function is the same as inflateReset, but it also permits changing
875 the wrap and window size requests. The windowBits parameter is interpreted
876 the same as it is for inflateInit2.
877
878 inflateReset2 returns Z_OK if success, or Z_STREAM_ERROR if the source
879 stream state was inconsistent (such as zalloc or state being Z_NULL), or if
880 the windowBits parameter is invalid.
881 */
882
883 ZEXTERN int ZEXPORT inflatePrime OF((z_streamp strm,
884 int bits,
885 int value));
886 /*
887 This function inserts bits in the inflate input stream. The intent is
888 that this function is used to start inflating at a bit position in the
889 middle of a byte. The provided bits will be used before any bytes are used
890 from next_in. This function should only be used with raw inflate, and
891 should be used before the first inflate() call after inflateInit2() or
892 inflateReset(). bits must be less than or equal to 16, and that many of the
893 least significant bits of value will be inserted in the input.
894
895 If bits is negative, then the input stream bit buffer is emptied. Then
896 inflatePrime() can be called again to put bits in the buffer. This is used
897 to clear out bits leftover after feeding inflate a block description prior
898 to feeding inflate codes.
899
900 inflatePrime returns Z_OK if success, or Z_STREAM_ERROR if the source
901 stream state was inconsistent.
902 */
903
904 ZEXTERN long ZEXPORT inflateMark OF((z_streamp strm));
905 /*
906 This function returns two values, one in the lower 16 bits of the return
907 value, and the other in the remaining upper bits, obtained by shifting the
908 return value down 16 bits. If the upper value is -1 and the lower value is
909 zero, then inflate() is currently decoding information outside of a block.
910 If the upper value is -1 and the lower value is non-zero, then inflate is in
911 the middle of a stored block, with the lower value equaling the number of
912 bytes from the input remaining to copy. If the upper value is not -1, then
913 it is the number of bits back from the current bit position in the input of
914 the code (literal or length/distance pair) currently being processed. In
915 that case the lower value is the number of bytes already emitted for that
916 code.
917
918 A code is being processed if inflate is waiting for more input to complete
919 decoding of the code, or if it has completed decoding but is waiting for
920 more output space to write the literal or match data.
921
922 inflateMark() is used to mark locations in the input data for random
923 access, which may be at bit positions, and to note those cases where the
924 output of a code may span boundaries of random access blocks. The current
925 location in the input stream can be determined from avail_in and data_type
926 as noted in the description for the Z_BLOCK flush parameter for inflate.
927
928 inflateMark returns the value noted above or -1 << 16 if the provided
929 source stream state was inconsistent.
930 */
931
932 ZEXTERN int ZEXPORT inflateGetHeader OF((z_streamp strm,
933 gz_headerp head));
934 /*
935 inflateGetHeader() requests that gzip header information be stored in the
936 provided gz_header structure. inflateGetHeader() may be called after
937 inflateInit2() or inflateReset(), and before the first call of inflate().
938 As inflate() processes the gzip stream, head->done is zero until the header
939 is completed, at which time head->done is set to one. If a zlib stream is
940 being decoded, then head->done is set to -1 to indicate that there will be
941 no gzip header information forthcoming. Note that Z_BLOCK or Z_TREES can be
942 used to force inflate() to return immediately after header processing is
943 complete and before any actual data is decompressed.
944
945 The text, time, xflags, and os fields are filled in with the gzip header
946 contents. hcrc is set to true if there is a header CRC. (The header CRC
947 was valid if done is set to one.) If extra is not Z_NULL, then extra_max
948 contains the maximum number of bytes to write to extra. Once done is true,
949 extra_len contains the actual extra field length, and extra contains the
950 extra field, or that field truncated if extra_max is less than extra_len.
951 If name is not Z_NULL, then up to name_max characters are written there,
952 terminated with a zero unless the length is greater than name_max. If
953 comment is not Z_NULL, then up to comm_max characters are written there,
954 terminated with a zero unless the length is greater than comm_max. When any
955 of extra, name, or comment are not Z_NULL and the respective field is not
956 present in the header, then that field is set to Z_NULL to signal its
957 absence. This allows the use of deflateSetHeader() with the returned
958 structure to duplicate the header. However if those fields are set to
959 allocated memory, then the application will need to save those pointers
960 elsewhere so that they can be eventually freed.
961
962 If inflateGetHeader is not used, then the header information is simply
963 discarded. The header is always checked for validity, including the header
964 CRC if present. inflateReset() will reset the process to discard the header
965 information. The application would need to call inflateGetHeader() again to
966 retrieve the header from the next gzip stream.
967
968 inflateGetHeader returns Z_OK if success, or Z_STREAM_ERROR if the source
969 stream state was inconsistent.
970 */
971
972 /*
973 ZEXTERN int ZEXPORT inflateBackInit OF((z_streamp strm, int windowBits,
974 unsigned char FAR *window));
975
976 Initialize the internal stream state for decompression using inflateBack()
977 calls. The fields zalloc, zfree and opaque in strm must be initialized
978 before the call. If zalloc and zfree are Z_NULL, then the default library-
979 derived memory allocation routines are used. windowBits is the base two
980 logarithm of the window size, in the range 8..15. window is a caller
981 supplied buffer of that size. Except for special applications where it is
982 assured that deflate was used with small window sizes, windowBits must be 15
983 and a 32K byte window must be supplied to be able to decompress general
984 deflate streams.
985
986 See inflateBack() for the usage of these routines.
987
988 inflateBackInit will return Z_OK on success, Z_STREAM_ERROR if any of
989 the paramaters are invalid, Z_MEM_ERROR if the internal state could not be
990 allocated, or Z_VERSION_ERROR if the version of the library does not match
991 the version of the header file.
992 */
993
994 typedef unsigned (*in_func) OF((void FAR *, unsigned char FAR * FAR *));
995 typedef int (*out_func) OF((void FAR *, unsigned char FAR *, unsigned));
996
997 ZEXTERN int ZEXPORT inflateBack OF((z_streamp strm,
998 in_func in, void FAR *in_desc,
999 out_func out, void FAR *out_desc));
1000 /*
1001 inflateBack() does a raw inflate with a single call using a call-back
1002 interface for input and output. This is more efficient than inflate() for
1003 file i/o applications in that it avoids copying between the output and the
1004 sliding window by simply making the window itself the output buffer. This
1005 function trusts the application to not change the output buffer passed by
1006 the output function, at least until inflateBack() returns.
1007
1008 inflateBackInit() must be called first to allocate the internal state
1009 and to initialize the state with the user-provided window buffer.
1010 inflateBack() may then be used multiple times to inflate a complete, raw
1011 deflate stream with each call. inflateBackEnd() is then called to free the
1012 allocated state.
1013
1014 A raw deflate stream is one with no zlib or gzip header or trailer.
1015 This routine would normally be used in a utility that reads zip or gzip
1016 files and writes out uncompressed files. The utility would decode the
1017 header and process the trailer on its own, hence this routine expects only
1018 the raw deflate stream to decompress. This is different from the normal
1019 behavior of inflate(), which expects either a zlib or gzip header and
1020 trailer around the deflate stream.
1021
1022 inflateBack() uses two subroutines supplied by the caller that are then
1023 called by inflateBack() for input and output. inflateBack() calls those
1024 routines until it reads a complete deflate stream and writes out all of the
1025 uncompressed data, or until it encounters an error. The function's
1026 parameters and return types are defined above in the in_func and out_func
1027 typedefs. inflateBack() will call in(in_desc, &buf) which should return the
1028 number of bytes of provided input, and a pointer to that input in buf. If
1029 there is no input available, in() must return zero--buf is ignored in that
1030 case--and inflateBack() will return a buffer error. inflateBack() will call
1031 out(out_desc, buf, len) to write the uncompressed data buf[0..len-1]. out()
1032 should return zero on success, or non-zero on failure. If out() returns
1033 non-zero, inflateBack() will return with an error. Neither in() nor out()
1034 are permitted to change the contents of the window provided to
1035 inflateBackInit(), which is also the buffer that out() uses to write from.
1036 The length written by out() will be at most the window size. Any non-zero
1037 amount of input may be provided by in().
1038
1039 For convenience, inflateBack() can be provided input on the first call by
1040 setting strm->next_in and strm->avail_in. If that input is exhausted, then
1041 in() will be called. Therefore strm->next_in must be initialized before
1042 calling inflateBack(). If strm->next_in is Z_NULL, then in() will be called
1043 immediately for input. If strm->next_in is not Z_NULL, then strm->avail_in
1044 must also be initialized, and then if strm->avail_in is not zero, input will
1045 initially be taken from strm->next_in[0 .. strm->avail_in - 1].
1046
1047 The in_desc and out_desc parameters of inflateBack() is passed as the
1048 first parameter of in() and out() respectively when they are called. These
1049 descriptors can be optionally used to pass any information that the caller-
1050 supplied in() and out() functions need to do their job.
1051
1052 On return, inflateBack() will set strm->next_in and strm->avail_in to
1053 pass back any unused input that was provided by the last in() call. The
1054 return values of inflateBack() can be Z_STREAM_END on success, Z_BUF_ERROR
1055 if in() or out() returned an error, Z_DATA_ERROR if there was a format error
1056 in the deflate stream (in which case strm->msg is set to indicate the nature
1057 of the error), or Z_STREAM_ERROR if the stream was not properly initialized.
1058 In the case of Z_BUF_ERROR, an input or output error can be distinguished
1059 using strm->next_in which will be Z_NULL only if in() returned an error. If
1060 strm->next_in is not Z_NULL, then the Z_BUF_ERROR was due to out() returning
1061 non-zero. (in() will always be called before out(), so strm->next_in is
1062 assured to be defined if out() returns non-zero.) Note that inflateBack()
1063 cannot return Z_OK.
1064 */
1065
1066 ZEXTERN int ZEXPORT inflateBackEnd OF((z_streamp strm));
1067 /*
1068 All memory allocated by inflateBackInit() is freed.
1069
1070 inflateBackEnd() returns Z_OK on success, or Z_STREAM_ERROR if the stream
1071 state was inconsistent.
1072 */
1073
1074 ZEXTERN uLong ZEXPORT zlibCompileFlags OF((void));
1075 /* Return flags indicating compile-time options.
1076
1077 Type sizes, two bits each, 00 = 16 bits, 01 = 32, 10 = 64, 11 = other:
1078 1.0: size of uInt
1079 3.2: size of uLong
1080 5.4: size of voidpf (pointer)
1081 7.6: size of z_off_t
1082
1083 Compiler, assembler, and debug options:
1084 8: DEBUG
1085 9: ASMV or ASMINF -- use ASM code
1086 10: ZLIB_WINAPI -- exported functions use the WINAPI calling convention
1087 11: 0 (reserved)
1088
1089 One-time table building (smaller code, but not thread-safe if true):
1090 12: BUILDFIXED -- build static block decoding tables when needed
1091 13: DYNAMIC_CRC_TABLE -- build CRC calculation tables when needed
1092 14,15: 0 (reserved)
1093
1094 Library content (indicates missing functionality):
1095 16: NO_GZCOMPRESS -- gz* functions cannot compress (to avoid linking
1096 deflate code when not needed)
1097 17: NO_GZIP -- deflate can't write gzip streams, and inflate can't detect
1098 and decode gzip streams (to avoid linking crc code)
1099 18-19: 0 (reserved)
1100
1101 Operation variations (changes in library functionality):
1102 20: PKZIP_BUG_WORKAROUND -- slightly more permissive inflate
1103 21: FASTEST -- deflate algorithm with only one, lowest compression level
1104 22,23: 0 (reserved)
1105
1106 The sprintf variant used by gzprintf (zero is best):
1107 24: 0 = vs*, 1 = s* -- 1 means limited to 20 arguments after the format
1108 25: 0 = *nprintf, 1 = *printf -- 1 means gzprintf() not secure!
1109 26: 0 = returns value, 1 = void -- 1 means inferred string length returned
1110
1111 Remainder:
1112 27-31: 0 (reserved)
1113 */
1114
1115
1116 /* utility functions */
1117
1118 /*
1119 The following utility functions are implemented on top of the basic
1120 stream-oriented functions. To simplify the interface, some default options
1121 are assumed (compression level and memory usage, standard memory allocation
1122 functions). The source code of these utility functions can be modified if
1123 you need special options.
1124 */
1125
1126 ZEXTERN int ZEXPORT compress OF((Bytef *dest, uLongf *destLen,
1127 const Bytef *source, uLong sourceLen));
1128 /*
1129 Compresses the source buffer into the destination buffer. sourceLen is
1130 the byte length of the source buffer. Upon entry, destLen is the total size
1131 of the destination buffer, which must be at least the value returned by
1132 compressBound(sourceLen). Upon exit, destLen is the actual size of the
1133 compressed buffer.
1134
1135 compress returns Z_OK if success, Z_MEM_ERROR if there was not
1136 enough memory, Z_BUF_ERROR if there was not enough room in the output
1137 buffer.
1138 */
1139
1140 ZEXTERN int ZEXPORT compress2 OF((Bytef *dest, uLongf *destLen,
1141 const Bytef *source, uLong sourceLen,
1142 int level));
1143 /*
1144 Compresses the source buffer into the destination buffer. The level
1145 parameter has the same meaning as in deflateInit. sourceLen is the byte
1146 length of the source buffer. Upon entry, destLen is the total size of the
1147 destination buffer, which must be at least the value returned by
1148 compressBound(sourceLen). Upon exit, destLen is the actual size of the
1149 compressed buffer.
1150
1151 compress2 returns Z_OK if success, Z_MEM_ERROR if there was not enough
1152 memory, Z_BUF_ERROR if there was not enough room in the output buffer,
1153 Z_STREAM_ERROR if the level parameter is invalid.
1154 */
1155
1156 ZEXTERN uLong ZEXPORT compressBound OF((uLong sourceLen));
1157 /*
1158 compressBound() returns an upper bound on the compressed size after
1159 compress() or compress2() on sourceLen bytes. It would be used before a
1160 compress() or compress2() call to allocate the destination buffer.
1161 */
1162
1163 ZEXTERN int ZEXPORT uncompress OF((Bytef *dest, uLongf *destLen,
1164 const Bytef *source, uLong sourceLen));
1165 /*
1166 Decompresses the source buffer into the destination buffer. sourceLen is
1167 the byte length of the source buffer. Upon entry, destLen is the total size
1168 of the destination buffer, which must be large enough to hold the entire
1169 uncompressed data. (The size of the uncompressed data must have been saved
1170 previously by the compressor and transmitted to the decompressor by some
1171 mechanism outside the scope of this compression library.) Upon exit, destLen
1172 is the actual size of the uncompressed buffer.
1173
1174 uncompress returns Z_OK if success, Z_MEM_ERROR if there was not
1175 enough memory, Z_BUF_ERROR if there was not enough room in the output
1176 buffer, or Z_DATA_ERROR if the input data was corrupted or incomplete.
1177 */
1178
1179
1180 /* gzip file access functions */
1181
1182 /*
1183 This library supports reading and writing files in gzip (.gz) format with
1184 an interface similar to that of stdio, using the functions that start with
1185 "gz". The gzip format is different from the zlib format. gzip is a gzip
1186 wrapper, documented in RFC 1952, wrapped around a deflate stream.
1187 */
1188
1189 typedef voidp gzFile; /* opaque gzip file descriptor */
1190
1191 /*
1192 ZEXTERN gzFile ZEXPORT gzopen OF((const char *path, const char *mode));
1193
1194 Opens a gzip (.gz) file for reading or writing. The mode parameter is as
1195 in fopen ("rb" or "wb") but can also include a compression level ("wb9") or
1196 a strategy: 'f' for filtered data as in "wb6f", 'h' for Huffman-only
1197 compression as in "wb1h", 'R' for run-length encoding as in "wb1R", or 'F'
1198 for fixed code compression as in "wb9F". (See the description of
1199 deflateInit2 for more information about the strategy parameter.) Also "a"
1200 can be used instead of "w" to request that the gzip stream that will be
1201 written be appended to the file. "+" will result in an error, since reading
1202 and writing to the same gzip file is not supported.
1203
1204 gzopen can be used to read a file which is not in gzip format; in this
1205 case gzread will directly read from the file without decompression.
1206
1207 gzopen returns NULL if the file could not be opened, if there was
1208 insufficient memory to allocate the gzFile state, or if an invalid mode was
1209 specified (an 'r', 'w', or 'a' was not provided, or '+' was provided).
1210 errno can be checked to determine if the reason gzopen failed was that the
1211 file could not be opened.
1212 */
1213
1214 ZEXTERN gzFile ZEXPORT gzdopen OF((int fd, const char *mode));
1215 /*
1216 gzdopen associates a gzFile with the file descriptor fd. File descriptors
1217 are obtained from calls like open, dup, creat, pipe or fileno (if the file
1218 has been previously opened with fopen). The mode parameter is as in gzopen.
1219
1220 The next call of gzclose on the returned gzFile will also close the file
1221 descriptor fd, just like fclose(fdopen(fd, mode)) closes the file descriptor
1222 fd. If you want to keep fd open, use fd = dup(fd_keep); gz = gzdopen(fd,
1223 mode);. The duplicated descriptor should be saved to avoid a leak, since
1224 gzdopen does not close fd if it fails.
1225
1226 gzdopen returns NULL if there was insufficient memory to allocate the
1227 gzFile state, if an invalid mode was specified (an 'r', 'w', or 'a' was not
1228 provided, or '+' was provided), or if fd is -1. The file descriptor is not
1229 used until the next gz* read, write, seek, or close operation, so gzdopen
1230 will not detect if fd is invalid (unless fd is -1).
1231 */
1232
1233 ZEXTERN int ZEXPORT gzbuffer OF((gzFile file, unsigned size));
1234 /*
1235 Set the internal buffer size used by this library's functions. The
1236 default buffer size is 8192 bytes. This function must be called after
1237 gzopen() or gzdopen(), and before any other calls that read or write the
1238 file. The buffer memory allocation is always deferred to the first read or
1239 write. Two buffers are allocated, either both of the specified size when
1240 writing, or one of the specified size and the other twice that size when
1241 reading. A larger buffer size of, for example, 64K or 128K bytes will
1242 noticeably increase the speed of decompression (reading).
1243
1244 The new buffer size also affects the maximum length for gzprintf().
1245
1246 gzbuffer() returns 0 on success, or -1 on failure, such as being called
1247 too late.
1248 */
1249
1250 ZEXTERN int ZEXPORT gzsetparams OF((gzFile file, int level, int strategy));
1251 /*
1252 Dynamically update the compression level or strategy. See the description
1253 of deflateInit2 for the meaning of these parameters.
1254
1255 gzsetparams returns Z_OK if success, or Z_STREAM_ERROR if the file was not
1256 opened for writing.
1257 */
1258
1259 ZEXTERN int ZEXPORT gzread OF((gzFile file, voidp buf, unsigned len));
1260 /*
1261 Reads the given number of uncompressed bytes from the compressed file. If
1262 the input file was not in gzip format, gzread copies the given number of
1263 bytes into the buffer.
1264
1265 After reaching the end of a gzip stream in the input, gzread will continue
1266 to read, looking for another gzip stream, or failing that, reading the rest
1267 of the input file directly without decompression. The entire input file
1268 will be read if gzread is called until it returns less than the requested
1269 len.
1270
1271 gzread returns the number of uncompressed bytes actually read, less than
1272 len for end of file, or -1 for error.
1273 */
1274
1275 ZEXTERN int ZEXPORT gzwrite OF((gzFile file,
1276 voidpc buf, unsigned len));
1277 /*
1278 Writes the given number of uncompressed bytes into the compressed file.
1279 gzwrite returns the number of uncompressed bytes written or 0 in case of
1280 error.
1281 */
1282
1283 ZEXTERN int ZEXPORTVA gzprintf OF((gzFile file, const char *format, ...));
1284 /*
1285 Converts, formats, and writes the arguments to the compressed file under
1286 control of the format string, as in fprintf. gzprintf returns the number of
1287 uncompressed bytes actually written, or 0 in case of error. The number of
1288 uncompressed bytes written is limited to 8191, or one less than the buffer
1289 size given to gzbuffer(). The caller should assure that this limit is not
1290 exceeded. If it is exceeded, then gzprintf() will return an error (0) with
1291 nothing written. In this case, there may also be a buffer overflow with
1292 unpredictable consequences, which is possible only if zlib was compiled with
1293 the insecure functions sprintf() or vsprintf() because the secure snprintf()
1294 or vsnprintf() functions were not available. This can be determined using
1295 zlibCompileFlags().
1296 */
1297
1298 ZEXTERN int ZEXPORT gzputs OF((gzFile file, const char *s));
1299 /*
1300 Writes the given null-terminated string to the compressed file, excluding
1301 the terminating null character.
1302
1303 gzputs returns the number of characters written, or -1 in case of error.
1304 */
1305
1306 ZEXTERN char * ZEXPORT gzgets OF((gzFile file, char *buf, int len));
1307 /*
1308 Reads bytes from the compressed file until len-1 characters are read, or a
1309 newline character is read and transferred to buf, or an end-of-file
1310 condition is encountered. If any characters are read or if len == 1, the
1311 string is terminated with a null character. If no characters are read due
1312 to an end-of-file or len < 1, then the buffer is left untouched.
1313
1314 gzgets returns buf which is a null-terminated string, or it returns NULL
1315 for end-of-file or in case of error. If there was an error, the contents at
1316 buf are indeterminate.
1317 */
1318
1319 ZEXTERN int ZEXPORT gzputc OF((gzFile file, int c));
1320 /*
1321 Writes c, converted to an unsigned char, into the compressed file. gzputc
1322 returns the value that was written, or -1 in case of error.
1323 */
1324
1325 ZEXTERN int ZEXPORT gzgetc OF((gzFile file));
1326 /*
1327 Reads one byte from the compressed file. gzgetc returns this byte or -1
1328 in case of end of file or error.
1329 */
1330
1331 ZEXTERN int ZEXPORT gzungetc OF((int c, gzFile file));
1332 /*
1333 Push one character back onto the stream to be read as the first character
1334 on the next read. At least one character of push-back is allowed.
1335 gzungetc() returns the character pushed, or -1 on failure. gzungetc() will
1336 fail if c is -1, and may fail if a character has been pushed but not read
1337 yet. If gzungetc is used immediately after gzopen or gzdopen, at least the
1338 output buffer size of pushed characters is allowed. (See gzbuffer above.)
1339 The pushed character will be discarded if the stream is repositioned with
1340 gzseek() or gzrewind().
1341 */
1342
1343 ZEXTERN int ZEXPORT gzflush OF((gzFile file, int flush));
1344 /*
1345 Flushes all pending output into the compressed file. The parameter flush
1346 is as in the deflate() function. The return value is the zlib error number
1347 (see function gzerror below). gzflush is only permitted when writing.
1348
1349 If the flush parameter is Z_FINISH, the remaining data is written and the
1350 gzip stream is completed in the output. If gzwrite() is called again, a new
1351 gzip stream will be started in the output. gzread() is able to read such
1352 concatented gzip streams.
1353
1354 gzflush should be called only when strictly necessary because it will
1355 degrade compression if called too often.
1356 */
1357
1358 /*
1359 ZEXTERN z_off_t ZEXPORT gzseek OF((gzFile file,
1360 z_off_t offset, int whence));
1361
1362 Sets the starting position for the next gzread or gzwrite on the given
1363 compressed file. The offset represents a number of bytes in the
1364 uncompressed data stream. The whence parameter is defined as in lseek(2);
1365 the value SEEK_END is not supported.
1366
1367 If the file is opened for reading, this function is emulated but can be
1368 extremely slow. If the file is opened for writing, only forward seeks are
1369 supported; gzseek then compresses a sequence of zeroes up to the new
1370 starting position.
1371
1372 gzseek returns the resulting offset location as measured in bytes from
1373 the beginning of the uncompressed stream, or -1 in case of error, in
1374 particular if the file is opened for writing and the new starting position
1375 would be before the current position.
1376 */
1377
1378 ZEXTERN int ZEXPORT gzrewind OF((gzFile file));
1379 /*
1380 Rewinds the given file. This function is supported only for reading.
1381
1382 gzrewind(file) is equivalent to (int)gzseek(file, 0L, SEEK_SET)
1383 */
1384
1385 /*
1386 ZEXTERN z_off_t ZEXPORT gztell OF((gzFile file));
1387
1388 Returns the starting position for the next gzread or gzwrite on the given
1389 compressed file. This position represents a number of bytes in the
1390 uncompressed data stream, and is zero when starting, even if appending or
1391 reading a gzip stream from the middle of a file using gzdopen().
1392
1393 gztell(file) is equivalent to gzseek(file, 0L, SEEK_CUR)
1394 */
1395
1396 /*
1397 ZEXTERN z_off_t ZEXPORT gzoffset OF((gzFile file));
1398
1399 Returns the current offset in the file being read or written. This offset
1400 includes the count of bytes that precede the gzip stream, for example when
1401 appending or when using gzdopen() for reading. When reading, the offset
1402 does not include as yet unused buffered input. This information can be used
1403 for a progress indicator. On error, gzoffset() returns -1.
1404 */
1405
1406 ZEXTERN int ZEXPORT gzeof OF((gzFile file));
1407 /*
1408 Returns true (1) if the end-of-file indicator has been set while reading,
1409 false (0) otherwise. Note that the end-of-file indicator is set only if the
1410 read tried to go past the end of the input, but came up short. Therefore,
1411 just like feof(), gzeof() may return false even if there is no more data to
1412 read, in the event that the last read request was for the exact number of
1413 bytes remaining in the input file. This will happen if the input file size
1414 is an exact multiple of the buffer size.
1415
1416 If gzeof() returns true, then the read functions will return no more data,
1417 unless the end-of-file indicator is reset by gzclearerr() and the input file
1418 has grown since the previous end of file was detected.
1419 */
1420
1421 ZEXTERN int ZEXPORT gzdirect OF((gzFile file));
1422 /*
1423 Returns true (1) if file is being copied directly while reading, or false
1424 (0) if file is a gzip stream being decompressed. This state can change from
1425 false to true while reading the input file if the end of a gzip stream is
1426 reached, but is followed by data that is not another gzip stream.
1427
1428 If the input file is empty, gzdirect() will return true, since the input
1429 does not contain a gzip stream.
1430
1431 If gzdirect() is used immediately after gzopen() or gzdopen() it will
1432 cause buffers to be allocated to allow reading the file to determine if it
1433 is a gzip file. Therefore if gzbuffer() is used, it should be called before
1434 gzdirect().
1435 */
1436
1437 ZEXTERN int ZEXPORT gzclose OF((gzFile file));
1438 /*
1439 Flushes all pending output if necessary, closes the compressed file and
1440 deallocates the (de)compression state. Note that once file is closed, you
1441 cannot call gzerror with file, since its structures have been deallocated.
1442 gzclose must not be called more than once on the same file, just as free
1443 must not be called more than once on the same allocation.
1444
1445 gzclose will return Z_STREAM_ERROR if file is not valid, Z_ERRNO on a
1446 file operation error, or Z_OK on success.
1447 */
1448
1449 ZEXTERN int ZEXPORT gzclose_r OF((gzFile file));
1450 ZEXTERN int ZEXPORT gzclose_w OF((gzFile file));
1451 /*
1452 Same as gzclose(), but gzclose_r() is only for use when reading, and
1453 gzclose_w() is only for use when writing or appending. The advantage to
1454 using these instead of gzclose() is that they avoid linking in zlib
1455 compression or decompression code that is not used when only reading or only
1456 writing respectively. If gzclose() is used, then both compression and
1457 decompression code will be included the application when linking to a static
1458 zlib library.
1459 */
1460
1461 ZEXTERN const char * ZEXPORT gzerror OF((gzFile file, int *errnum));
1462 /*
1463 Returns the error message for the last error which occurred on the given
1464 compressed file. errnum is set to zlib error number. If an error occurred
1465 in the file system and not in the compression library, errnum is set to
1466 Z_ERRNO and the application may consult errno to get the exact error code.
1467
1468 The application must not modify the returned string. Future calls to
1469 this function may invalidate the previously returned string. If file is
1470 closed, then the string previously returned by gzerror will no longer be
1471 available.
1472
1473 gzerror() should be used to distinguish errors from end-of-file for those
1474 functions above that do not distinguish those cases in their return values.
1475 */
1476
1477 ZEXTERN void ZEXPORT gzclearerr OF((gzFile file));
1478 /*
1479 Clears the error and end-of-file flags for file. This is analogous to the
1480 clearerr() function in stdio. This is useful for continuing to read a gzip
1481 file that is being written concurrently.
1482 */
1483
1484
1485 /* checksum functions */
1486
1487 /*
1488 These functions are not related to compression but are exported
1489 anyway because they might be useful in applications using the compression
1490 library.
1491 */
1492
1493 ZEXTERN uLong ZEXPORT adler32 OF((uLong adler, const Bytef *buf, uInt len));
1494 /*
1495 Update a running Adler-32 checksum with the bytes buf[0..len-1] and
1496 return the updated checksum. If buf is Z_NULL, this function returns the
1497 required initial value for the checksum.
1498
1499 An Adler-32 checksum is almost as reliable as a CRC32 but can be computed
1500 much faster.
1501
1502 Usage example:
1503
1504 uLong adler = adler32(0L, Z_NULL, 0);
1505
1506 while (read_buffer(buffer, length) != EOF) {
1507 adler = adler32(adler, buffer, length);
1508 }
1509 if (adler != original_adler) error();
1510 */
1511
1512 /*
1513 ZEXTERN uLong ZEXPORT adler32_combine OF((uLong adler1, uLong adler2,
1514 z_off_t len2));
1515
1516 Combine two Adler-32 checksums into one. For two sequences of bytes, seq1
1517 and seq2 with lengths len1 and len2, Adler-32 checksums were calculated for
1518 each, adler1 and adler2. adler32_combine() returns the Adler-32 checksum of
1519 seq1 and seq2 concatenated, requiring only adler1, adler2, and len2.
1520 */
1521
1522 ZEXTERN uLong ZEXPORT crc32 OF((uLong crc, const Bytef *buf, uInt len));
1523 /*
1524 Update a running CRC-32 with the bytes buf[0..len-1] and return the
1525 updated CRC-32. If buf is Z_NULL, this function returns the required
1526 initial value for the for the crc. Pre- and post-conditioning (one's
1527 complement) is performed within this function so it shouldn't be done by the
1528 application.
1529
1530 Usage example:
1531
1532 uLong crc = crc32(0L, Z_NULL, 0);
1533
1534 while (read_buffer(buffer, length) != EOF) {
1535 crc = crc32(crc, buffer, length);
1536 }
1537 if (crc != original_crc) error();
1538 */
1539
1540 /*
1541 ZEXTERN uLong ZEXPORT crc32_combine OF((uLong crc1, uLong crc2, z_off_t len2));
1542
1543 Combine two CRC-32 check values into one. For two sequences of bytes,
1544 seq1 and seq2 with lengths len1 and len2, CRC-32 check values were
1545 calculated for each, crc1 and crc2. crc32_combine() returns the CRC-32
1546 check value of seq1 and seq2 concatenated, requiring only crc1, crc2, and
1547 len2.
1548 */
1549
1550
1551 /* various hacks, don't look :) */
1552
1553 /* deflateInit and inflateInit are macros to allow checking the zlib version
1554 * and the compiler's view of z_stream:
1555 */
1556 ZEXTERN int ZEXPORT deflateInit_ OF((z_streamp strm, int level,
1557 const char *version, int stream_size));
1558 ZEXTERN int ZEXPORT inflateInit_ OF((z_streamp strm,
1559 const char *version, int stream_size));
1560 ZEXTERN int ZEXPORT deflateInit2_ OF((z_streamp strm, int level, int method,
1561 int windowBits, int memLevel,
1562 int strategy, const char *version,
1563 int stream_size));
1564 ZEXTERN int ZEXPORT inflateInit2_ OF((z_streamp strm, int windowBits,
1565 const char *version, int stream_size));
1566 ZEXTERN int ZEXPORT inflateBackInit_ OF((z_streamp strm, int windowBits,
1567 unsigned char FAR *window,
1568 const char *version,
1569 int stream_size));
1570 #define deflateInit(strm, level) \
1571 deflateInit_((strm), (level), ZLIB_VERSION, sizeof(z_stream))
1572 #define inflateInit(strm) \
1573 inflateInit_((strm), ZLIB_VERSION, sizeof(z_stream))
1574 #define deflateInit2(strm, level, method, windowBits, memLevel, strategy) \
1575 deflateInit2_((strm),(level),(method),(windowBits),(memLevel),\
1576 (strategy), ZLIB_VERSION, sizeof(z_stream))
1577 #define inflateInit2(strm, windowBits) \
1578 inflateInit2_((strm), (windowBits), ZLIB_VERSION, sizeof(z_stream))
1579 #define inflateBackInit(strm, windowBits, window) \
1580 inflateBackInit_((strm), (windowBits), (window), \
1581 ZLIB_VERSION, sizeof(z_stream))
1582
1583 /* provide 64-bit offset functions if _LARGEFILE64_SOURCE defined, and/or
1584 * change the regular functions to 64 bits if _FILE_OFFSET_BITS is 64 (if
1585 * both are true, the application gets the *64 functions, and the regular
1586 * functions are changed to 64 bits) -- in case these are set on systems
1587 * without large file support, _LFS64_LARGEFILE must also be true
1588 */
1589 #if defined(_LARGEFILE64_SOURCE) && _LFS64_LARGEFILE-0
1590 ZEXTERN gzFile ZEXPORT gzopen64 OF((const char *, const char *));
1591 ZEXTERN z_off64_t ZEXPORT gzseek64 OF((gzFile, z_off64_t, int));
1592 ZEXTERN z_off64_t ZEXPORT gztell64 OF((gzFile));
1593 ZEXTERN z_off64_t ZEXPORT gzoffset64 OF((gzFile));
1594 ZEXTERN uLong ZEXPORT adler32_combine64 OF((uLong, uLong, z_off64_t));
1595 ZEXTERN uLong ZEXPORT crc32_combine64 OF((uLong, uLong, z_off64_t));
1596 #endif
1597
1598 #if !defined(ZLIB_INTERNAL) && _FILE_OFFSET_BITS-0 == 64 && _LFS64_LARGEFILE-0
1599 # define gzopen gzopen64
1600 # define gzseek gzseek64
1601 # define gztell gztell64
1602 # define gzoffset gzoffset64
1603 # define adler32_combine adler32_combine64
1604 # define crc32_combine crc32_combine64
1605 # ifdef _LARGEFILE64_SOURCE
1606 ZEXTERN gzFile ZEXPORT gzopen64 OF((const char *, const char *));
1607 ZEXTERN z_off_t ZEXPORT gzseek64 OF((gzFile, z_off_t, int));
1608 ZEXTERN z_off_t ZEXPORT gztell64 OF((gzFile));
1609 ZEXTERN z_off_t ZEXPORT gzoffset64 OF((gzFile));
1610 ZEXTERN uLong ZEXPORT adler32_combine64 OF((uLong, uLong, z_off_t));
1611 ZEXTERN uLong ZEXPORT crc32_combine64 OF((uLong, uLong, z_off_t));
1612 # endif
1613 #else
1614 ZEXTERN gzFile ZEXPORT gzopen OF((const char *, const char *));
1615 ZEXTERN z_off_t ZEXPORT gzseek OF((gzFile, z_off_t, int));
1616 ZEXTERN z_off_t ZEXPORT gztell OF((gzFile));
1617 ZEXTERN z_off_t ZEXPORT gzoffset OF((gzFile));
1618 ZEXTERN uLong ZEXPORT adler32_combine OF((uLong, uLong, z_off_t));
1619 ZEXTERN uLong ZEXPORT crc32_combine OF((uLong, uLong, z_off_t));
1620 #endif
1621
1622 /* hack for buggy compilers */
1623 #if !defined(ZUTIL_H) && !defined(NO_DUMMY_DECL)
1624 struct internal_state {int dummy;};
1625 #endif
1626
1627 /* undocumented functions */
1628 ZEXTERN const char * ZEXPORT zError OF((int));
1629 ZEXTERN int ZEXPORT inflateSyncPoint OF((z_streamp));
1630 ZEXTERN const unsigned long FAR * ZEXPORT get_crc_table OF((void));
1631 ZEXTERN int ZEXPORT inflateUndermine OF((z_streamp, int));
1632
1633 #ifdef __cplusplus
1634 }
1635 #endif
1636
1637 #endif /* ZLIB_H */