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libs/zlib-1.2.6: fix OSE

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1/* zlib.h -- interface of the 'zlib' general purpose compression library
2 version 1.2.6, January 29th, 2012
3
4 Copyright (C) 1995-2012 Jean-loup Gailly and Mark Adler
5
6 This software is provided 'as-is', without any express or implied
7 warranty. In no event will the authors be held liable for any damages
8 arising from the use of this software.
9
10 Permission is granted to anyone to use this software for any purpose,
11 including commercial applications, and to alter it and redistribute it
12 freely, subject to the following restrictions:
13
14 1. The origin of this software must not be misrepresented; you must not
15 claim that you wrote the original software. If you use this software
16 in a product, an acknowledgment in the product documentation would be
17 appreciated but is not required.
18 2. Altered source versions must be plainly marked as such, and must not be
19 misrepresented as being the original software.
20 3. This notice may not be removed or altered from any source distribution.
21
22 Jean-loup Gailly Mark Adler
23 [email protected] [email protected]
24
25
26 The data format used by the zlib library is described by RFCs (Request for
27 Comments) 1950 to 1952 in the files http://tools.ietf.org/html/rfc1950
28 (zlib format), rfc1951 (deflate format) and rfc1952 (gzip format).
29*/
30
31#ifndef ZLIB_H
32#define ZLIB_H
33
34#include "zconf.h"
35
36#ifdef __cplusplus
37extern "C" {
38#endif
39
40#define ZLIB_VERSION "1.2.6"
41#define ZLIB_VERNUM 0x1260
42#define ZLIB_VER_MAJOR 1
43#define ZLIB_VER_MINOR 2
44#define ZLIB_VER_REVISION 6
45#define ZLIB_VER_SUBREVISION 0
46
47/*
48 The 'zlib' compression library provides in-memory compression and
49 decompression functions, including integrity checks of the uncompressed data.
50 This version of the library supports only one compression method (deflation)
51 but other algorithms will be added later and will have the same stream
52 interface.
53
54 Compression can be done in a single step if the buffers are large enough,
55 or can be done by repeated calls of the compression function. In the latter
56 case, the application must provide more input and/or consume the output
57 (providing more output space) before each call.
58
59 The compressed data format used by default by the in-memory functions is
60 the zlib format, which is a zlib wrapper documented in RFC 1950, wrapped
61 around a deflate stream, which is itself documented in RFC 1951.
62
63 The library also supports reading and writing files in gzip (.gz) format
64 with an interface similar to that of stdio using the functions that start
65 with "gz". The gzip format is different from the zlib format. gzip is a
66 gzip wrapper, documented in RFC 1952, wrapped around a deflate stream.
67
68 This library can optionally read and write gzip streams in memory as well.
69
70 The zlib format was designed to be compact and fast for use in memory
71 and on communications channels. The gzip format was designed for single-
72 file compression on file systems, has a larger header than zlib to maintain
73 directory information, and uses a different, slower check method than zlib.
74
75 The library does not install any signal handler. The decoder checks
76 the consistency of the compressed data, so the library should never crash
77 even in case of corrupted input.
78*/
79
80typedef voidpf (*alloc_func) OF((voidpf opaque, uInt items, uInt size));
81typedef void (*free_func) OF((voidpf opaque, voidpf address));
82
83struct internal_state;
84
85typedef struct z_stream_s {
86 z_const Bytef *next_in; /* next input byte */
87 uInt avail_in; /* number of bytes available at next_in */
88 uLong total_in; /* total number of input bytes read so far */
89
90 Bytef *next_out; /* next output byte should be put there */
91 uInt avail_out; /* remaining free space at next_out */
92 uLong total_out; /* total number of bytes output so far */
93
94 z_const char *msg; /* last error message, NULL if no error */
95 struct internal_state FAR *state; /* not visible by applications */
96
97 alloc_func zalloc; /* used to allocate the internal state */
98 free_func zfree; /* used to free the internal state */
99 voidpf opaque; /* private data object passed to zalloc and zfree */
100
101 int data_type; /* best guess about the data type: binary or text */
102 uLong adler; /* adler32 value of the uncompressed data */
103 uLong reserved; /* reserved for future use */
104} z_stream;
105
106typedef z_stream FAR *z_streamp;
107
108/*
109 gzip header information passed to and from zlib routines. See RFC 1952
110 for more details on the meanings of these fields.
111*/
112typedef struct gz_header_s {
113 int text; /* true if compressed data believed to be text */
114 uLong time; /* modification time */
115 int xflags; /* extra flags (not used when writing a gzip file) */
116 int os; /* operating system */
117 Bytef *extra; /* pointer to extra field or Z_NULL if none */
118 uInt extra_len; /* extra field length (valid if extra != Z_NULL) */
119 uInt extra_max; /* space at extra (only when reading header) */
120 Bytef *name; /* pointer to zero-terminated file name or Z_NULL */
121 uInt name_max; /* space at name (only when reading header) */
122 Bytef *comment; /* pointer to zero-terminated comment or Z_NULL */
123 uInt comm_max; /* space at comment (only when reading header) */
124 int hcrc; /* true if there was or will be a header crc */
125 int done; /* true when done reading gzip header (not used
126 when writing a gzip file) */
127} gz_header;
128
129typedef gz_header FAR *gz_headerp;
130
131/*
132 The application must update next_in and avail_in when avail_in has dropped
133 to zero. It must update next_out and avail_out when avail_out has dropped
134 to zero. The application must initialize zalloc, zfree and opaque before
135 calling the init function. All other fields are set by the compression
136 library and must not be updated by the application.
137
138 The opaque value provided by the application will be passed as the first
139 parameter for calls of zalloc and zfree. This can be useful for custom
140 memory management. The compression library attaches no meaning to the
141 opaque value.
142
143 zalloc must return Z_NULL if there is not enough memory for the object.
144 If zlib is used in a multi-threaded application, zalloc and zfree must be
145 thread safe.
146
147 On 16-bit systems, the functions zalloc and zfree must be able to allocate
148 exactly 65536 bytes, but will not be required to allocate more than this if
149 the symbol MAXSEG_64K is defined (see zconf.h). WARNING: On MSDOS, pointers
150 returned by zalloc for objects of exactly 65536 bytes *must* have their
151 offset normalized to zero. The default allocation function provided by this
152 library ensures this (see zutil.c). To reduce memory requirements and avoid
153 any allocation of 64K objects, at the expense of compression ratio, compile
154 the library with -DMAX_WBITS=14 (see zconf.h).
155
156 The fields total_in and total_out can be used for statistics or progress
157 reports. After compression, total_in holds the total size of the
158 uncompressed data and may be saved for use in the decompressor (particularly
159 if the decompressor wants to decompress everything in a single step).
160*/
161
162 /* constants */
163
164#define Z_NO_FLUSH 0
165#define Z_PARTIAL_FLUSH 1
166#define Z_SYNC_FLUSH 2
167#define Z_FULL_FLUSH 3
168#define Z_FINISH 4
169#define Z_BLOCK 5
170#define Z_TREES 6
171/* Allowed flush values; see deflate() and inflate() below for details */
172
173#define Z_OK 0
174#define Z_STREAM_END 1
175#define Z_NEED_DICT 2
176#define Z_ERRNO (-1)
177#define Z_STREAM_ERROR (-2)
178#define Z_DATA_ERROR (-3)
179#define Z_MEM_ERROR (-4)
180#define Z_BUF_ERROR (-5)
181#define Z_VERSION_ERROR (-6)
182/* Return codes for the compression/decompression functions. Negative values
183 * are errors, positive values are used for special but normal events.
184 */
185
186#define Z_NO_COMPRESSION 0
187#define Z_BEST_SPEED 1
188#define Z_BEST_COMPRESSION 9
189#define Z_DEFAULT_COMPRESSION (-1)
190/* compression levels */
191
192#define Z_FILTERED 1
193#define Z_HUFFMAN_ONLY 2
194#define Z_RLE 3
195#define Z_FIXED 4
196#define Z_DEFAULT_STRATEGY 0
197/* compression strategy; see deflateInit2() below for details */
198
199#define Z_BINARY 0
200#define Z_TEXT 1
201#define Z_ASCII Z_TEXT /* for compatibility with 1.2.2 and earlier */
202#define Z_UNKNOWN 2
203/* Possible values of the data_type field (though see inflate()) */
204
205#define Z_DEFLATED 8
206/* The deflate compression method (the only one supported in this version) */
207
208#define Z_NULL 0 /* for initializing zalloc, zfree, opaque */
209
210#define zlib_version zlibVersion()
211/* for compatibility with versions < 1.0.2 */
212
213
214 /* basic functions */
215
216ZEXTERN const char * ZEXPORT zlibVersion OF((void));
217/* The application can compare zlibVersion and ZLIB_VERSION for consistency.
218 If the first character differs, the library code actually used is not
219 compatible with the zlib.h header file used by the application. This check
220 is automatically made by deflateInit and inflateInit.
221 */
222
223/*
224ZEXTERN int ZEXPORT deflateInit OF((z_streamp strm, int level));
225
226 Initializes the internal stream state for compression. The fields
227 zalloc, zfree and opaque must be initialized before by the caller. If
228 zalloc and zfree are set to Z_NULL, deflateInit updates them to use default
229 allocation functions.
230
231 The compression level must be Z_DEFAULT_COMPRESSION, or between 0 and 9:
232 1 gives best speed, 9 gives best compression, 0 gives no compression at all
233 (the input data is simply copied a block at a time). Z_DEFAULT_COMPRESSION
234 requests a default compromise between speed and compression (currently
235 equivalent to level 6).
236
237 deflateInit returns Z_OK if success, Z_MEM_ERROR if there was not enough
238 memory, Z_STREAM_ERROR if level is not a valid compression level, or
239 Z_VERSION_ERROR if the zlib library version (zlib_version) is incompatible
240 with the version assumed by the caller (ZLIB_VERSION). msg is set to null
241 if there is no error message. deflateInit does not perform any compression:
242 this will be done by deflate().
243*/
244
245
246ZEXTERN int ZEXPORT deflate OF((z_streamp strm, int flush));
247/*
248 deflate compresses as much data as possible, and stops when the input
249 buffer becomes empty or the output buffer becomes full. It may introduce
250 some output latency (reading input without producing any output) except when
251 forced to flush.
252
253 The detailed semantics are as follows. deflate performs one or both of the
254 following actions:
255
256 - Compress more input starting at next_in and update next_in and avail_in
257 accordingly. If not all input can be processed (because there is not
258 enough room in the output buffer), next_in and avail_in are updated and
259 processing will resume at this point for the next call of deflate().
260
261 - Provide more output starting at next_out and update next_out and avail_out
262 accordingly. This action is forced if the parameter flush is non zero.
263 Forcing flush frequently degrades the compression ratio, so this parameter
264 should be set only when necessary (in interactive applications). Some
265 output may be provided even if flush is not set.
266
267 Before the call of deflate(), the application should ensure that at least
268 one of the actions is possible, by providing more input and/or consuming more
269 output, and updating avail_in or avail_out accordingly; avail_out should
270 never be zero before the call. The application can consume the compressed
271 output when it wants, for example when the output buffer is full (avail_out
272 == 0), or after each call of deflate(). If deflate returns Z_OK and with
273 zero avail_out, it must be called again after making room in the output
274 buffer because there might be more output pending.
275
276 Normally the parameter flush is set to Z_NO_FLUSH, which allows deflate to
277 decide how much data to accumulate before producing output, in order to
278 maximize compression.
279
280 If the parameter flush is set to Z_SYNC_FLUSH, all pending output is
281 flushed to the output buffer and the output is aligned on a byte boundary, so
282 that the decompressor can get all input data available so far. (In
283 particular avail_in is zero after the call if enough output space has been
284 provided before the call.) Flushing may degrade compression for some
285 compression algorithms and so it should be used only when necessary. This
286 completes the current deflate block and follows it with an empty stored block
287 that is three bits plus filler bits to the next byte, followed by four bytes
288 (00 00 ff ff).
289
290 If flush is set to Z_PARTIAL_FLUSH, all pending output is flushed to the
291 output buffer, but the output is not aligned to a byte boundary. All of the
292 input data so far will be available to the decompressor, as for Z_SYNC_FLUSH.
293 This completes the current deflate block and follows it with an empty fixed
294 codes block that is 10 bits long. This assures that enough bytes are output
295 in order for the decompressor to finish the block before the empty fixed code
296 block.
297
298 If flush is set to Z_BLOCK, a deflate block is completed and emitted, as
299 for Z_SYNC_FLUSH, but the output is not aligned on a byte boundary, and up to
300 seven bits of the current block are held to be written as the next byte after
301 the next deflate block is completed. In this case, the decompressor may not
302 be provided enough bits at this point in order to complete decompression of
303 the data provided so far to the compressor. It may need to wait for the next
304 block to be emitted. This is for advanced applications that need to control
305 the emission of deflate blocks.
306
307 If flush is set to Z_FULL_FLUSH, all output is flushed as with
308 Z_SYNC_FLUSH, and the compression state is reset so that decompression can
309 restart from this point if previous compressed data has been damaged or if
310 random access is desired. Using Z_FULL_FLUSH too often can seriously degrade
311 compression.
312
313 If deflate returns with avail_out == 0, this function must be called again
314 with the same value of the flush parameter and more output space (updated
315 avail_out), until the flush is complete (deflate returns with non-zero
316 avail_out). In the case of a Z_FULL_FLUSH or Z_SYNC_FLUSH, make sure that
317 avail_out is greater than six to avoid repeated flush markers due to
318 avail_out == 0 on return.
319
320 If the parameter flush is set to Z_FINISH, pending input is processed,
321 pending output is flushed and deflate returns with Z_STREAM_END if there was
322 enough output space; if deflate returns with Z_OK, this function must be
323 called again with Z_FINISH and more output space (updated avail_out) but no
324 more input data, until it returns with Z_STREAM_END or an error. After
325 deflate has returned Z_STREAM_END, the only possible operations on the stream
326 are deflateReset or deflateEnd.
327
328 Z_FINISH can be used immediately after deflateInit if all the compression
329 is to be done in a single step. In this case, avail_out must be at least the
330 value returned by deflateBound (see below). Then deflate is guaranteed to
331 return Z_STREAM_END. If not enough output space is provided, deflate will
332 not return Z_STREAM_END, and it must be called again as described above.
333
334 deflate() sets strm->adler to the adler32 checksum of all input read
335 so far (that is, total_in bytes).
336
337 deflate() may update strm->data_type if it can make a good guess about
338 the input data type (Z_BINARY or Z_TEXT). In doubt, the data is considered
339 binary. This field is only for information purposes and does not affect the
340 compression algorithm in any manner.
341
342 deflate() returns Z_OK if some progress has been made (more input
343 processed or more output produced), Z_STREAM_END if all input has been
344 consumed and all output has been produced (only when flush is set to
345 Z_FINISH), Z_STREAM_ERROR if the stream state was inconsistent (for example
346 if next_in or next_out was Z_NULL), Z_BUF_ERROR if no progress is possible
347 (for example avail_in or avail_out was zero). Note that Z_BUF_ERROR is not
348 fatal, and deflate() can be called again with more input and more output
349 space to continue compressing.
350*/
351
352
353ZEXTERN int ZEXPORT deflateEnd OF((z_streamp strm));
354/*
355 All dynamically allocated data structures for this stream are freed.
356 This function discards any unprocessed input and does not flush any pending
357 output.
358
359 deflateEnd returns Z_OK if success, Z_STREAM_ERROR if the
360 stream state was inconsistent, Z_DATA_ERROR if the stream was freed
361 prematurely (some input or output was discarded). In the error case, msg
362 may be set but then points to a static string (which must not be
363 deallocated).
364*/
365
366
367/*
368ZEXTERN int ZEXPORT inflateInit OF((z_streamp strm));
369
370 Initializes the internal stream state for decompression. The fields
371 next_in, avail_in, zalloc, zfree and opaque must be initialized before by
372 the caller. If next_in is not Z_NULL and avail_in is large enough (the
373 exact value depends on the compression method), inflateInit determines the
374 compression method from the zlib header and allocates all data structures
375 accordingly; otherwise the allocation will be deferred to the first call of
376 inflate. If zalloc and zfree are set to Z_NULL, inflateInit updates them to
377 use default allocation functions.
378
379 inflateInit returns Z_OK if success, Z_MEM_ERROR if there was not enough
380 memory, Z_VERSION_ERROR if the zlib library version is incompatible with the
381 version assumed by the caller, or Z_STREAM_ERROR if the parameters are
382 invalid, such as a null pointer to the structure. msg is set to null if
383 there is no error message. inflateInit does not perform any decompression
384 apart from possibly reading the zlib header if present: actual decompression
385 will be done by inflate(). (So next_in and avail_in may be modified, but
386 next_out and avail_out are unused and unchanged.) The current implementation
387 of inflateInit() does not process any header information -- that is deferred
388 until inflate() is called.
389*/
390
391
392ZEXTERN int ZEXPORT inflate OF((z_streamp strm, int flush));
393/*
394 inflate decompresses as much data as possible, and stops when the input
395 buffer becomes empty or the output buffer becomes full. It may introduce
396 some output latency (reading input without producing any output) except when
397 forced to flush.
398
399 The detailed semantics are as follows. inflate performs one or both of the
400 following actions:
401
402 - Decompress more input starting at next_in and update next_in and avail_in
403 accordingly. If not all input can be processed (because there is not
404 enough room in the output buffer), next_in is updated and processing will
405 resume at this point for the next call of inflate().
406
407 - Provide more output starting at next_out and update next_out and avail_out
408 accordingly. inflate() provides as much output as possible, until there is
409 no more input data or no more space in the output buffer (see below about
410 the flush parameter).
411
412 Before the call of inflate(), the application should ensure that at least
413 one of the actions is possible, by providing more input and/or consuming more
414 output, and updating the next_* and avail_* values accordingly. The
415 application can consume the uncompressed output when it wants, for example
416 when the output buffer is full (avail_out == 0), or after each call of
417 inflate(). If inflate returns Z_OK and with zero avail_out, it must be
418 called again after making room in the output buffer because there might be
419 more output pending.
420
421 The flush parameter of inflate() can be Z_NO_FLUSH, Z_SYNC_FLUSH, Z_FINISH,
422 Z_BLOCK, or Z_TREES. Z_SYNC_FLUSH requests that inflate() flush as much
423 output as possible to the output buffer. Z_BLOCK requests that inflate()
424 stop if and when it gets to the next deflate block boundary. When decoding
425 the zlib or gzip format, this will cause inflate() to return immediately
426 after the header and before the first block. When doing a raw inflate,
427 inflate() will go ahead and process the first block, and will return when it
428 gets to the end of that block, or when it runs out of data.
429
430 The Z_BLOCK option assists in appending to or combining deflate streams.
431 Also to assist in this, on return inflate() will set strm->data_type to the
432 number of unused bits in the last byte taken from strm->next_in, plus 64 if
433 inflate() is currently decoding the last block in the deflate stream, plus
434 128 if inflate() returned immediately after decoding an end-of-block code or
435 decoding the complete header up to just before the first byte of the deflate
436 stream. The end-of-block will not be indicated until all of the uncompressed
437 data from that block has been written to strm->next_out. The number of
438 unused bits may in general be greater than seven, except when bit 7 of
439 data_type is set, in which case the number of unused bits will be less than
440 eight. data_type is set as noted here every time inflate() returns for all
441 flush options, and so can be used to determine the amount of currently
442 consumed input in bits.
443
444 The Z_TREES option behaves as Z_BLOCK does, but it also returns when the
445 end of each deflate block header is reached, before any actual data in that
446 block is decoded. This allows the caller to determine the length of the
447 deflate block header for later use in random access within a deflate block.
448 256 is added to the value of strm->data_type when inflate() returns
449 immediately after reaching the end of the deflate block header.
450
451 inflate() should normally be called until it returns Z_STREAM_END or an
452 error. However if all decompression is to be performed in a single step (a
453 single call of inflate), the parameter flush should be set to Z_FINISH. In
454 this case all pending input is processed and all pending output is flushed;
455 avail_out must be large enough to hold all the uncompressed data. (The size
456 of the uncompressed data may have been saved by the compressor for this
457 purpose.) The next operation on this stream must be inflateEnd to deallocate
458 the decompression state. The use of Z_FINISH is not required to perform an
459 inflation in one step. However it may be used to inform inflate that a
460 faster approach can be used for the single inflate() call. Z_FINISH also
461 informs inflate to not maintain a sliding window if the stream completes,
462 which reduces inflate's memory footprint.
463
464 In this implementation, inflate() always flushes as much output as
465 possible to the output buffer, and always uses the faster approach on the
466 first call. So the effects of the flush parameter in this implementation are
467 on the return value of inflate() as noted below, when inflate() returns early
468 when Z_BLOCK or Z_TREES is used, and when inflate() avoids the allocation of
469 memory for a sliding window when Z_FINISH is used.
470
471 If a preset dictionary is needed after this call (see inflateSetDictionary
472 below), inflate sets strm->adler to the Adler-32 checksum of the dictionary
473 chosen by the compressor and returns Z_NEED_DICT; otherwise it sets
474 strm->adler to the Adler-32 checksum of all output produced so far (that is,
475 total_out bytes) and returns Z_OK, Z_STREAM_END or an error code as described
476 below. At the end of the stream, inflate() checks that its computed adler32
477 checksum is equal to that saved by the compressor and returns Z_STREAM_END
478 only if the checksum is correct.
479
480 inflate() can decompress and check either zlib-wrapped or gzip-wrapped
481 deflate data. The header type is detected automatically, if requested when
482 initializing with inflateInit2(). Any information contained in the gzip
483 header is not retained, so applications that need that information should
484 instead use raw inflate, see inflateInit2() below, or inflateBack() and
485 perform their own processing of the gzip header and trailer. When processing
486 gzip-wrapped deflate data, strm->adler32 is set to the CRC-32 of the output
487 producted so far. The CRC-32 is checked against the gzip trailer.
488
489 inflate() returns Z_OK if some progress has been made (more input processed
490 or more output produced), Z_STREAM_END if the end of the compressed data has
491 been reached and all uncompressed output has been produced, Z_NEED_DICT if a
492 preset dictionary is needed at this point, Z_DATA_ERROR if the input data was
493 corrupted (input stream not conforming to the zlib format or incorrect check
494 value), Z_STREAM_ERROR if the stream structure was inconsistent (for example
495 next_in or next_out was Z_NULL), Z_MEM_ERROR if there was not enough memory,
496 Z_BUF_ERROR if no progress is possible or if there was not enough room in the
497 output buffer when Z_FINISH is used. Note that Z_BUF_ERROR is not fatal, and
498 inflate() can be called again with more input and more output space to
499 continue decompressing. If Z_DATA_ERROR is returned, the application may
500 then call inflateSync() to look for a good compression block if a partial
501 recovery of the data is desired.
502*/
503
504
505ZEXTERN int ZEXPORT inflateEnd OF((z_streamp strm));
506/*
507 All dynamically allocated data structures for this stream are freed.
508 This function discards any unprocessed input and does not flush any pending
509 output.
510
511 inflateEnd returns Z_OK if success, Z_STREAM_ERROR if the stream state
512 was inconsistent. In the error case, msg may be set but then points to a
513 static string (which must not be deallocated).
514*/
515
516
517 /* Advanced functions */
518
519/*
520 The following functions are needed only in some special applications.
521*/
522
523/*
524ZEXTERN int ZEXPORT deflateInit2 OF((z_streamp strm,
525 int level,
526 int method,
527 int windowBits,
528 int memLevel,
529 int strategy));
530
531 This is another version of deflateInit with more compression options. The
532 fields next_in, zalloc, zfree and opaque must be initialized before by the
533 caller.
534
535 The method parameter is the compression method. It must be Z_DEFLATED in
536 this version of the library.
537
538 The windowBits parameter is the base two logarithm of the window size
539 (the size of the history buffer). It should be in the range 8..15 for this
540 version of the library. Larger values of this parameter result in better
541 compression at the expense of memory usage. The default value is 15 if
542 deflateInit is used instead.
543
544 windowBits can also be -8..-15 for raw deflate. In this case, -windowBits
545 determines the window size. deflate() will then generate raw deflate data
546 with no zlib header or trailer, and will not compute an adler32 check value.
547
548 windowBits can also be greater than 15 for optional gzip encoding. Add
549 16 to windowBits to write a simple gzip header and trailer around the
550 compressed data instead of a zlib wrapper. The gzip header will have no
551 file name, no extra data, no comment, no modification time (set to zero), no
552 header crc, and the operating system will be set to 255 (unknown). If a
553 gzip stream is being written, strm->adler is a crc32 instead of an adler32.
554
555 The memLevel parameter specifies how much memory should be allocated
556 for the internal compression state. memLevel=1 uses minimum memory but is
557 slow and reduces compression ratio; memLevel=9 uses maximum memory for
558 optimal speed. The default value is 8. See zconf.h for total memory usage
559 as a function of windowBits and memLevel.
560
561 The strategy parameter is used to tune the compression algorithm. Use the
562 value Z_DEFAULT_STRATEGY for normal data, Z_FILTERED for data produced by a
563 filter (or predictor), Z_HUFFMAN_ONLY to force Huffman encoding only (no
564 string match), or Z_RLE to limit match distances to one (run-length
565 encoding). Filtered data consists mostly of small values with a somewhat
566 random distribution. In this case, the compression algorithm is tuned to
567 compress them better. The effect of Z_FILTERED is to force more Huffman
568 coding and less string matching; it is somewhat intermediate between
569 Z_DEFAULT_STRATEGY and Z_HUFFMAN_ONLY. Z_RLE is designed to be almost as
570 fast as Z_HUFFMAN_ONLY, but give better compression for PNG image data. The
571 strategy parameter only affects the compression ratio but not the
572 correctness of the compressed output even if it is not set appropriately.
573 Z_FIXED prevents the use of dynamic Huffman codes, allowing for a simpler
574 decoder for special applications.
575
576 deflateInit2 returns Z_OK if success, Z_MEM_ERROR if there was not enough
577 memory, Z_STREAM_ERROR if any parameter is invalid (such as an invalid
578 method), or Z_VERSION_ERROR if the zlib library version (zlib_version) is
579 incompatible with the version assumed by the caller (ZLIB_VERSION). msg is
580 set to null if there is no error message. deflateInit2 does not perform any
581 compression: this will be done by deflate().
582*/
583
584ZEXTERN int ZEXPORT deflateSetDictionary OF((z_streamp strm,
585 const Bytef *dictionary,
586 uInt dictLength));
587/*
588 Initializes the compression dictionary from the given byte sequence
589 without producing any compressed output. When using the zlib format, this
590 function must be called immediately after deflateInit, deflateInit2 or
591 deflateReset, and before any call of deflate. When doing raw deflate, this
592 function must be called either before any call of deflate, or immediately
593 after the completion of a deflate block, i.e. after all input has been
594 consumed and all output has been delivered when using any of the flush
595 options Z_BLOCK, Z_PARTIAL_FLUSH, Z_SYNC_FLUSH, or Z_FULL_FLUSH. The
596 compressor and decompressor must use exactly the same dictionary (see
597 inflateSetDictionary).
598
599 The dictionary should consist of strings (byte sequences) that are likely
600 to be encountered later in the data to be compressed, with the most commonly
601 used strings preferably put towards the end of the dictionary. Using a
602 dictionary is most useful when the data to be compressed is short and can be
603 predicted with good accuracy; the data can then be compressed better than
604 with the default empty dictionary.
605
606 Depending on the size of the compression data structures selected by
607 deflateInit or deflateInit2, a part of the dictionary may in effect be
608 discarded, for example if the dictionary is larger than the window size
609 provided in deflateInit or deflateInit2. Thus the strings most likely to be
610 useful should be put at the end of the dictionary, not at the front. In
611 addition, the current implementation of deflate will use at most the window
612 size minus 262 bytes of the provided dictionary.
613
614 Upon return of this function, strm->adler is set to the adler32 value
615 of the dictionary; the decompressor may later use this value to determine
616 which dictionary has been used by the compressor. (The adler32 value
617 applies to the whole dictionary even if only a subset of the dictionary is
618 actually used by the compressor.) If a raw deflate was requested, then the
619 adler32 value is not computed and strm->adler is not set.
620
621 deflateSetDictionary returns Z_OK if success, or Z_STREAM_ERROR if a
622 parameter is invalid (e.g. dictionary being Z_NULL) or the stream state is
623 inconsistent (for example if deflate has already been called for this stream
624 or if not at a block boundary for raw deflate). deflateSetDictionary does
625 not perform any compression: this will be done by deflate().
626*/
627
628ZEXTERN int ZEXPORT deflateCopy OF((z_streamp dest,
629 z_streamp source));
630/*
631 Sets the destination stream as a complete copy of the source stream.
632
633 This function can be useful when several compression strategies will be
634 tried, for example when there are several ways of pre-processing the input
635 data with a filter. The streams that will be discarded should then be freed
636 by calling deflateEnd. Note that deflateCopy duplicates the internal
637 compression state which can be quite large, so this strategy is slow and can
638 consume lots of memory.
639
640 deflateCopy returns Z_OK if success, Z_MEM_ERROR if there was not
641 enough memory, Z_STREAM_ERROR if the source stream state was inconsistent
642 (such as zalloc being Z_NULL). msg is left unchanged in both source and
643 destination.
644*/
645
646ZEXTERN int ZEXPORT deflateReset OF((z_streamp strm));
647/*
648 This function is equivalent to deflateEnd followed by deflateInit,
649 but does not free and reallocate all the internal compression state. The
650 stream will keep the same compression level and any other attributes that
651 may have been set by deflateInit2.
652
653 deflateReset returns Z_OK if success, or Z_STREAM_ERROR if the source
654 stream state was inconsistent (such as zalloc or state being Z_NULL).
655*/
656
657ZEXTERN int ZEXPORT deflateParams OF((z_streamp strm,
658 int level,
659 int strategy));
660/*
661 Dynamically update the compression level and compression strategy. The
662 interpretation of level and strategy is as in deflateInit2. This can be
663 used to switch between compression and straight copy of the input data, or
664 to switch to a different kind of input data requiring a different strategy.
665 If the compression level is changed, the input available so far is
666 compressed with the old level (and may be flushed); the new level will take
667 effect only at the next call of deflate().
668
669 Before the call of deflateParams, the stream state must be set as for
670 a call of deflate(), since the currently available input may have to be
671 compressed and flushed. In particular, strm->avail_out must be non-zero.
672
673 deflateParams returns Z_OK if success, Z_STREAM_ERROR if the source
674 stream state was inconsistent or if a parameter was invalid, Z_BUF_ERROR if
675 strm->avail_out was zero.
676*/
677
678ZEXTERN int ZEXPORT deflateTune OF((z_streamp strm,
679 int good_length,
680 int max_lazy,
681 int nice_length,
682 int max_chain));
683/*
684 Fine tune deflate's internal compression parameters. This should only be
685 used by someone who understands the algorithm used by zlib's deflate for
686 searching for the best matching string, and even then only by the most
687 fanatic optimizer trying to squeeze out the last compressed bit for their
688 specific input data. Read the deflate.c source code for the meaning of the
689 max_lazy, good_length, nice_length, and max_chain parameters.
690
691 deflateTune() can be called after deflateInit() or deflateInit2(), and
692 returns Z_OK on success, or Z_STREAM_ERROR for an invalid deflate stream.
693 */
694
695ZEXTERN uLong ZEXPORT deflateBound OF((z_streamp strm,
696 uLong sourceLen));
697/*
698 deflateBound() returns an upper bound on the compressed size after
699 deflation of sourceLen bytes. It must be called after deflateInit() or
700 deflateInit2(), and after deflateSetHeader(), if used. This would be used
701 to allocate an output buffer for deflation in a single pass, and so would be
702 called before deflate(). If that first deflate() call is provided the
703 sourceLen input bytes, an output buffer allocated to the size returned by
704 deflateBound(), and the flush value Z_FINISH, then deflate() is guaranteed
705 to return Z_STREAM_END. Note that it is possible for the compressed size to
706 be larger than the value returned by deflateBound() if flush options other
707 than Z_FINISH or Z_NO_FLUSH are used.
708*/
709
710ZEXTERN int ZEXPORT deflatePending OF((z_streamp strm,
711 unsigned *pending,
712 int *bits));
713/*
714 deflatePending() returns the number of bytes and bits of output that have
715 been generated, but not yet provided in the available output. The bytes not
716 provided would be due to the available output space having being consumed.
717 The number of bits of output not provided are between 0 and 7, where they
718 await more bits to join them in order to fill out a full byte. If pending
719 or bits are Z_NULL, then those values are not set.
720
721 deflatePending returns Z_OK if success, or Z_STREAM_ERROR if the source
722 stream state was inconsistent.
723 */
724
725ZEXTERN int ZEXPORT deflatePrime OF((z_streamp strm,
726 int bits,
727 int value));
728/*
729 deflatePrime() inserts bits in the deflate output stream. The intent
730 is that this function is used to start off the deflate output with the bits
731 leftover from a previous deflate stream when appending to it. As such, this
732 function can only be used for raw deflate, and must be used before the first
733 deflate() call after a deflateInit2() or deflateReset(). bits must be less
734 than or equal to 16, and that many of the least significant bits of value
735 will be inserted in the output.
736
737 deflatePrime returns Z_OK if success, Z_BUF_ERROR if there was not enough
738 room in the internal buffer to insert the bits, or Z_STREAM_ERROR if the
739 source stream state was inconsistent.
740*/
741
742ZEXTERN int ZEXPORT deflateSetHeader OF((z_streamp strm,
743 gz_headerp head));
744/*
745 deflateSetHeader() provides gzip header information for when a gzip
746 stream is requested by deflateInit2(). deflateSetHeader() may be called
747 after deflateInit2() or deflateReset() and before the first call of
748 deflate(). The text, time, os, extra field, name, and comment information
749 in the provided gz_header structure are written to the gzip header (xflag is
750 ignored -- the extra flags are set according to the compression level). The
751 caller must assure that, if not Z_NULL, name and comment are terminated with
752 a zero byte, and that if extra is not Z_NULL, that extra_len bytes are
753 available there. If hcrc is true, a gzip header crc is included. Note that
754 the current versions of the command-line version of gzip (up through version
755 1.3.x) do not support header crc's, and will report that it is a "multi-part
756 gzip file" and give up.
757
758 If deflateSetHeader is not used, the default gzip header has text false,
759 the time set to zero, and os set to 255, with no extra, name, or comment
760 fields. The gzip header is returned to the default state by deflateReset().
761
762 deflateSetHeader returns Z_OK if success, or Z_STREAM_ERROR if the source
763 stream state was inconsistent.
764*/
765
766/*
767ZEXTERN int ZEXPORT inflateInit2 OF((z_streamp strm,
768 int windowBits));
769
770 This is another version of inflateInit with an extra parameter. The
771 fields next_in, avail_in, zalloc, zfree and opaque must be initialized
772 before by the caller.
773
774 The windowBits parameter is the base two logarithm of the maximum window
775 size (the size of the history buffer). It should be in the range 8..15 for
776 this version of the library. The default value is 15 if inflateInit is used
777 instead. windowBits must be greater than or equal to the windowBits value
778 provided to deflateInit2() while compressing, or it must be equal to 15 if
779 deflateInit2() was not used. If a compressed stream with a larger window
780 size is given as input, inflate() will return with the error code
781 Z_DATA_ERROR instead of trying to allocate a larger window.
782
783 windowBits can also be zero to request that inflate use the window size in
784 the zlib header of the compressed stream.
785
786 windowBits can also be -8..-15 for raw inflate. In this case, -windowBits
787 determines the window size. inflate() will then process raw deflate data,
788 not looking for a zlib or gzip header, not generating a check value, and not
789 looking for any check values for comparison at the end of the stream. This
790 is for use with other formats that use the deflate compressed data format
791 such as zip. Those formats provide their own check values. If a custom
792 format is developed using the raw deflate format for compressed data, it is
793 recommended that a check value such as an adler32 or a crc32 be applied to
794 the uncompressed data as is done in the zlib, gzip, and zip formats. For
795 most applications, the zlib format should be used as is. Note that comments
796 above on the use in deflateInit2() applies to the magnitude of windowBits.
797
798 windowBits can also be greater than 15 for optional gzip decoding. Add
799 32 to windowBits to enable zlib and gzip decoding with automatic header
800 detection, or add 16 to decode only the gzip format (the zlib format will
801 return a Z_DATA_ERROR). If a gzip stream is being decoded, strm->adler is a
802 crc32 instead of an adler32.
803
804 inflateInit2 returns Z_OK if success, Z_MEM_ERROR if there was not enough
805 memory, Z_VERSION_ERROR if the zlib library version is incompatible with the
806 version assumed by the caller, or Z_STREAM_ERROR if the parameters are
807 invalid, such as a null pointer to the structure. msg is set to null if
808 there is no error message. inflateInit2 does not perform any decompression
809 apart from possibly reading the zlib header if present: actual decompression
810 will be done by inflate(). (So next_in and avail_in may be modified, but
811 next_out and avail_out are unused and unchanged.) The current implementation
812 of inflateInit2() does not process any header information -- that is
813 deferred until inflate() is called.
814*/
815
816ZEXTERN int ZEXPORT inflateSetDictionary OF((z_streamp strm,
817 const Bytef *dictionary,
818 uInt dictLength));
819/*
820 Initializes the decompression dictionary from the given uncompressed byte
821 sequence. This function must be called immediately after a call of inflate,
822 if that call returned Z_NEED_DICT. The dictionary chosen by the compressor
823 can be determined from the adler32 value returned by that call of inflate.
824 The compressor and decompressor must use exactly the same dictionary (see
825 deflateSetDictionary). For raw inflate, this function can be called at any
826 time to set the dictionary. If the provided dictionary is smaller than the
827 window and there is already data in the window, then the provided dictionary
828 will amend what's there. The application must insure that the dictionary
829 that was used for compression is provided.
830
831 inflateSetDictionary returns Z_OK if success, Z_STREAM_ERROR if a
832 parameter is invalid (e.g. dictionary being Z_NULL) or the stream state is
833 inconsistent, Z_DATA_ERROR if the given dictionary doesn't match the
834 expected one (incorrect adler32 value). inflateSetDictionary does not
835 perform any decompression: this will be done by subsequent calls of
836 inflate().
837*/
838
839ZEXTERN int ZEXPORT inflateSync OF((z_streamp strm));
840/*
841 Skips invalid compressed data until a possible full flush point (see above
842 for the description of deflate with Z_FULL_FLUSH) can be found, or until all
843 available input is skipped. No output is provided.
844
845 inflateSync searches for a 00 00 FF FF pattern in the compressed data.
846 All full flush points have this pattern, but not all occurences of this
847 pattern are full flush points.
848
849 inflateSync returns Z_OK if a possible full flush point has been found,
850 Z_BUF_ERROR if no more input was provided, Z_DATA_ERROR if no flush point
851 has been found, or Z_STREAM_ERROR if the stream structure was inconsistent.
852 In the success case, the application may save the current current value of
853 total_in which indicates where valid compressed data was found. In the
854 error case, the application may repeatedly call inflateSync, providing more
855 input each time, until success or end of the input data.
856*/
857
858ZEXTERN int ZEXPORT inflateCopy OF((z_streamp dest,
859 z_streamp source));
860/*
861 Sets the destination stream as a complete copy of the source stream.
862
863 This function can be useful when randomly accessing a large stream. The
864 first pass through the stream can periodically record the inflate state,
865 allowing restarting inflate at those points when randomly accessing the
866 stream.
867
868 inflateCopy returns Z_OK if success, Z_MEM_ERROR if there was not
869 enough memory, Z_STREAM_ERROR if the source stream state was inconsistent
870 (such as zalloc being Z_NULL). msg is left unchanged in both source and
871 destination.
872*/
873
874ZEXTERN int ZEXPORT inflateReset OF((z_streamp strm));
875/*
876 This function is equivalent to inflateEnd followed by inflateInit,
877 but does not free and reallocate all the internal decompression state. The
878 stream will keep attributes that may have been set by inflateInit2.
879
880 inflateReset returns Z_OK if success, or Z_STREAM_ERROR if the source
881 stream state was inconsistent (such as zalloc or state being Z_NULL).
882*/
883
884ZEXTERN int ZEXPORT inflateReset2 OF((z_streamp strm,
885 int windowBits));
886/*
887 This function is the same as inflateReset, but it also permits changing
888 the wrap and window size requests. The windowBits parameter is interpreted
889 the same as it is for inflateInit2.
890
891 inflateReset2 returns Z_OK if success, or Z_STREAM_ERROR if the source
892 stream state was inconsistent (such as zalloc or state being Z_NULL), or if
893 the windowBits parameter is invalid.
894*/
895
896ZEXTERN int ZEXPORT inflatePrime OF((z_streamp strm,
897 int bits,
898 int value));
899/*
900 This function inserts bits in the inflate input stream. The intent is
901 that this function is used to start inflating at a bit position in the
902 middle of a byte. The provided bits will be used before any bytes are used
903 from next_in. This function should only be used with raw inflate, and
904 should be used before the first inflate() call after inflateInit2() or
905 inflateReset(). bits must be less than or equal to 16, and that many of the
906 least significant bits of value will be inserted in the input.
907
908 If bits is negative, then the input stream bit buffer is emptied. Then
909 inflatePrime() can be called again to put bits in the buffer. This is used
910 to clear out bits leftover after feeding inflate a block description prior
911 to feeding inflate codes.
912
913 inflatePrime returns Z_OK if success, or Z_STREAM_ERROR if the source
914 stream state was inconsistent.
915*/
916
917ZEXTERN long ZEXPORT inflateMark OF((z_streamp strm));
918/*
919 This function returns two values, one in the lower 16 bits of the return
920 value, and the other in the remaining upper bits, obtained by shifting the
921 return value down 16 bits. If the upper value is -1 and the lower value is
922 zero, then inflate() is currently decoding information outside of a block.
923 If the upper value is -1 and the lower value is non-zero, then inflate is in
924 the middle of a stored block, with the lower value equaling the number of
925 bytes from the input remaining to copy. If the upper value is not -1, then
926 it is the number of bits back from the current bit position in the input of
927 the code (literal or length/distance pair) currently being processed. In
928 that case the lower value is the number of bytes already emitted for that
929 code.
930
931 A code is being processed if inflate is waiting for more input to complete
932 decoding of the code, or if it has completed decoding but is waiting for
933 more output space to write the literal or match data.
934
935 inflateMark() is used to mark locations in the input data for random
936 access, which may be at bit positions, and to note those cases where the
937 output of a code may span boundaries of random access blocks. The current
938 location in the input stream can be determined from avail_in and data_type
939 as noted in the description for the Z_BLOCK flush parameter for inflate.
940
941 inflateMark returns the value noted above or -1 << 16 if the provided
942 source stream state was inconsistent.
943*/
944
945ZEXTERN int ZEXPORT inflateGetHeader OF((z_streamp strm,
946 gz_headerp head));
947/*
948 inflateGetHeader() requests that gzip header information be stored in the
949 provided gz_header structure. inflateGetHeader() may be called after
950 inflateInit2() or inflateReset(), and before the first call of inflate().
951 As inflate() processes the gzip stream, head->done is zero until the header
952 is completed, at which time head->done is set to one. If a zlib stream is
953 being decoded, then head->done is set to -1 to indicate that there will be
954 no gzip header information forthcoming. Note that Z_BLOCK or Z_TREES can be
955 used to force inflate() to return immediately after header processing is
956 complete and before any actual data is decompressed.
957
958 The text, time, xflags, and os fields are filled in with the gzip header
959 contents. hcrc is set to true if there is a header CRC. (The header CRC
960 was valid if done is set to one.) If extra is not Z_NULL, then extra_max
961 contains the maximum number of bytes to write to extra. Once done is true,
962 extra_len contains the actual extra field length, and extra contains the
963 extra field, or that field truncated if extra_max is less than extra_len.
964 If name is not Z_NULL, then up to name_max characters are written there,
965 terminated with a zero unless the length is greater than name_max. If
966 comment is not Z_NULL, then up to comm_max characters are written there,
967 terminated with a zero unless the length is greater than comm_max. When any
968 of extra, name, or comment are not Z_NULL and the respective field is not
969 present in the header, then that field is set to Z_NULL to signal its
970 absence. This allows the use of deflateSetHeader() with the returned
971 structure to duplicate the header. However if those fields are set to
972 allocated memory, then the application will need to save those pointers
973 elsewhere so that they can be eventually freed.
974
975 If inflateGetHeader is not used, then the header information is simply
976 discarded. The header is always checked for validity, including the header
977 CRC if present. inflateReset() will reset the process to discard the header
978 information. The application would need to call inflateGetHeader() again to
979 retrieve the header from the next gzip stream.
980
981 inflateGetHeader returns Z_OK if success, or Z_STREAM_ERROR if the source
982 stream state was inconsistent.
983*/
984
985/*
986ZEXTERN int ZEXPORT inflateBackInit OF((z_streamp strm, int windowBits,
987 unsigned char FAR *window));
988
989 Initialize the internal stream state for decompression using inflateBack()
990 calls. The fields zalloc, zfree and opaque in strm must be initialized
991 before the call. If zalloc and zfree are Z_NULL, then the default library-
992 derived memory allocation routines are used. windowBits is the base two
993 logarithm of the window size, in the range 8..15. window is a caller
994 supplied buffer of that size. Except for special applications where it is
995 assured that deflate was used with small window sizes, windowBits must be 15
996 and a 32K byte window must be supplied to be able to decompress general
997 deflate streams.
998
999 See inflateBack() for the usage of these routines.
1000
1001 inflateBackInit will return Z_OK on success, Z_STREAM_ERROR if any of
1002 the parameters are invalid, Z_MEM_ERROR if the internal state could not be
1003 allocated, or Z_VERSION_ERROR if the version of the library does not match
1004 the version of the header file.
1005*/
1006
1007typedef unsigned (*in_func) OF((void FAR *, unsigned char FAR * FAR *));
1008typedef int (*out_func) OF((void FAR *, unsigned char FAR *, unsigned));
1009
1010ZEXTERN int ZEXPORT inflateBack OF((z_streamp strm,
1011 in_func in, void FAR *in_desc,
1012 out_func out, void FAR *out_desc));
1013/*
1014 inflateBack() does a raw inflate with a single call using a call-back
1015 interface for input and output. This is more efficient than inflate() for
1016 file i/o applications in that it avoids copying between the output and the
1017 sliding window by simply making the window itself the output buffer. This
1018 function trusts the application to not change the output buffer passed by
1019 the output function, at least until inflateBack() returns.
1020
1021 inflateBackInit() must be called first to allocate the internal state
1022 and to initialize the state with the user-provided window buffer.
1023 inflateBack() may then be used multiple times to inflate a complete, raw
1024 deflate stream with each call. inflateBackEnd() is then called to free the
1025 allocated state.
1026
1027 A raw deflate stream is one with no zlib or gzip header or trailer.
1028 This routine would normally be used in a utility that reads zip or gzip
1029 files and writes out uncompressed files. The utility would decode the
1030 header and process the trailer on its own, hence this routine expects only
1031 the raw deflate stream to decompress. This is different from the normal
1032 behavior of inflate(), which expects either a zlib or gzip header and
1033 trailer around the deflate stream.
1034
1035 inflateBack() uses two subroutines supplied by the caller that are then
1036 called by inflateBack() for input and output. inflateBack() calls those
1037 routines until it reads a complete deflate stream and writes out all of the
1038 uncompressed data, or until it encounters an error. The function's
1039 parameters and return types are defined above in the in_func and out_func
1040 typedefs. inflateBack() will call in(in_desc, &buf) which should return the
1041 number of bytes of provided input, and a pointer to that input in buf. If
1042 there is no input available, in() must return zero--buf is ignored in that
1043 case--and inflateBack() will return a buffer error. inflateBack() will call
1044 out(out_desc, buf, len) to write the uncompressed data buf[0..len-1]. out()
1045 should return zero on success, or non-zero on failure. If out() returns
1046 non-zero, inflateBack() will return with an error. Neither in() nor out()
1047 are permitted to change the contents of the window provided to
1048 inflateBackInit(), which is also the buffer that out() uses to write from.
1049 The length written by out() will be at most the window size. Any non-zero
1050 amount of input may be provided by in().
1051
1052 For convenience, inflateBack() can be provided input on the first call by
1053 setting strm->next_in and strm->avail_in. If that input is exhausted, then
1054 in() will be called. Therefore strm->next_in must be initialized before
1055 calling inflateBack(). If strm->next_in is Z_NULL, then in() will be called
1056 immediately for input. If strm->next_in is not Z_NULL, then strm->avail_in
1057 must also be initialized, and then if strm->avail_in is not zero, input will
1058 initially be taken from strm->next_in[0 .. strm->avail_in - 1].
1059
1060 The in_desc and out_desc parameters of inflateBack() is passed as the
1061 first parameter of in() and out() respectively when they are called. These
1062 descriptors can be optionally used to pass any information that the caller-
1063 supplied in() and out() functions need to do their job.
1064
1065 On return, inflateBack() will set strm->next_in and strm->avail_in to
1066 pass back any unused input that was provided by the last in() call. The
1067 return values of inflateBack() can be Z_STREAM_END on success, Z_BUF_ERROR
1068 if in() or out() returned an error, Z_DATA_ERROR if there was a format error
1069 in the deflate stream (in which case strm->msg is set to indicate the nature
1070 of the error), or Z_STREAM_ERROR if the stream was not properly initialized.
1071 In the case of Z_BUF_ERROR, an input or output error can be distinguished
1072 using strm->next_in which will be Z_NULL only if in() returned an error. If
1073 strm->next_in is not Z_NULL, then the Z_BUF_ERROR was due to out() returning
1074 non-zero. (in() will always be called before out(), so strm->next_in is
1075 assured to be defined if out() returns non-zero.) Note that inflateBack()
1076 cannot return Z_OK.
1077*/
1078
1079ZEXTERN int ZEXPORT inflateBackEnd OF((z_streamp strm));
1080/*
1081 All memory allocated by inflateBackInit() is freed.
1082
1083 inflateBackEnd() returns Z_OK on success, or Z_STREAM_ERROR if the stream
1084 state was inconsistent.
1085*/
1086
1087ZEXTERN uLong ZEXPORT zlibCompileFlags OF((void));
1088/* Return flags indicating compile-time options.
1089
1090 Type sizes, two bits each, 00 = 16 bits, 01 = 32, 10 = 64, 11 = other:
1091 1.0: size of uInt
1092 3.2: size of uLong
1093 5.4: size of voidpf (pointer)
1094 7.6: size of z_off_t
1095
1096 Compiler, assembler, and debug options:
1097 8: DEBUG
1098 9: ASMV or ASMINF -- use ASM code
1099 10: ZLIB_WINAPI -- exported functions use the WINAPI calling convention
1100 11: 0 (reserved)
1101
1102 One-time table building (smaller code, but not thread-safe if true):
1103 12: BUILDFIXED -- build static block decoding tables when needed
1104 13: DYNAMIC_CRC_TABLE -- build CRC calculation tables when needed
1105 14,15: 0 (reserved)
1106
1107 Library content (indicates missing functionality):
1108 16: NO_GZCOMPRESS -- gz* functions cannot compress (to avoid linking
1109 deflate code when not needed)
1110 17: NO_GZIP -- deflate can't write gzip streams, and inflate can't detect
1111 and decode gzip streams (to avoid linking crc code)
1112 18-19: 0 (reserved)
1113
1114 Operation variations (changes in library functionality):
1115 20: PKZIP_BUG_WORKAROUND -- slightly more permissive inflate
1116 21: FASTEST -- deflate algorithm with only one, lowest compression level
1117 22,23: 0 (reserved)
1118
1119 The sprintf variant used by gzprintf (zero is best):
1120 24: 0 = vs*, 1 = s* -- 1 means limited to 20 arguments after the format
1121 25: 0 = *nprintf, 1 = *printf -- 1 means gzprintf() not secure!
1122 26: 0 = returns value, 1 = void -- 1 means inferred string length returned
1123
1124 Remainder:
1125 27-31: 0 (reserved)
1126 */
1127
1128#ifndef Z_SOLO
1129
1130 /* utility functions */
1131
1132/*
1133 The following utility functions are implemented on top of the basic
1134 stream-oriented functions. To simplify the interface, some default options
1135 are assumed (compression level and memory usage, standard memory allocation
1136 functions). The source code of these utility functions can be modified if
1137 you need special options.
1138*/
1139
1140ZEXTERN int ZEXPORT compress OF((Bytef *dest, uLongf *destLen,
1141 const Bytef *source, uLong sourceLen));
1142/*
1143 Compresses the source buffer into the destination buffer. sourceLen is
1144 the byte length of the source buffer. Upon entry, destLen is the total size
1145 of the destination buffer, which must be at least the value returned by
1146 compressBound(sourceLen). Upon exit, destLen is the actual size of the
1147 compressed buffer.
1148
1149 compress returns Z_OK if success, Z_MEM_ERROR if there was not
1150 enough memory, Z_BUF_ERROR if there was not enough room in the output
1151 buffer.
1152*/
1153
1154ZEXTERN int ZEXPORT compress2 OF((Bytef *dest, uLongf *destLen,
1155 const Bytef *source, uLong sourceLen,
1156 int level));
1157/*
1158 Compresses the source buffer into the destination buffer. The level
1159 parameter has the same meaning as in deflateInit. sourceLen is the byte
1160 length of the source buffer. Upon entry, destLen is the total size of the
1161 destination buffer, which must be at least the value returned by
1162 compressBound(sourceLen). Upon exit, destLen is the actual size of the
1163 compressed buffer.
1164
1165 compress2 returns Z_OK if success, Z_MEM_ERROR if there was not enough
1166 memory, Z_BUF_ERROR if there was not enough room in the output buffer,
1167 Z_STREAM_ERROR if the level parameter is invalid.
1168*/
1169
1170ZEXTERN uLong ZEXPORT compressBound OF((uLong sourceLen));
1171/*
1172 compressBound() returns an upper bound on the compressed size after
1173 compress() or compress2() on sourceLen bytes. It would be used before a
1174 compress() or compress2() call to allocate the destination buffer.
1175*/
1176
1177ZEXTERN int ZEXPORT uncompress OF((Bytef *dest, uLongf *destLen,
1178 const Bytef *source, uLong sourceLen));
1179/*
1180 Decompresses the source buffer into the destination buffer. sourceLen is
1181 the byte length of the source buffer. Upon entry, destLen is the total size
1182 of the destination buffer, which must be large enough to hold the entire
1183 uncompressed data. (The size of the uncompressed data must have been saved
1184 previously by the compressor and transmitted to the decompressor by some
1185 mechanism outside the scope of this compression library.) Upon exit, destLen
1186 is the actual size of the uncompressed buffer.
1187
1188 uncompress returns Z_OK if success, Z_MEM_ERROR if there was not
1189 enough memory, Z_BUF_ERROR if there was not enough room in the output
1190 buffer, or Z_DATA_ERROR if the input data was corrupted or incomplete. In
1191 the case where there is not enough room, uncompress() will fill the output
1192 buffer with the uncompressed data up to that point.
1193*/
1194
1195 /* gzip file access functions */
1196
1197/*
1198 This library supports reading and writing files in gzip (.gz) format with
1199 an interface similar to that of stdio, using the functions that start with
1200 "gz". The gzip format is different from the zlib format. gzip is a gzip
1201 wrapper, documented in RFC 1952, wrapped around a deflate stream.
1202*/
1203
1204typedef struct gzFile_s *gzFile; /* semi-opaque gzip file descriptor */
1205
1206/*
1207ZEXTERN gzFile ZEXPORT gzopen OF((const char *path, const char *mode));
1208
1209 Opens a gzip (.gz) file for reading or writing. The mode parameter is as
1210 in fopen ("rb" or "wb") but can also include a compression level ("wb9") or
1211 a strategy: 'f' for filtered data as in "wb6f", 'h' for Huffman-only
1212 compression as in "wb1h", 'R' for run-length encoding as in "wb1R", or 'F'
1213 for fixed code compression as in "wb9F". (See the description of
1214 deflateInit2 for more information about the strategy parameter.) 'T' will
1215 request transparent writing or appending with no compression and not using
1216 the gzip format.
1217
1218 "a" can be used instead of "w" to request that the gzip stream that will
1219 be written be appended to the file. "+" will result in an error, since
1220 reading and writing to the same gzip file is not supported.
1221
1222 These functions, as well as gzip, will read and decode a sequence of gzip
1223 streams in a file. The append function of gzopen() can be used to create
1224 such a file. (Also see gzflush() for another way to do this.) When
1225 appending, gzopen does not test whether the file begins with a gzip stream,
1226 nor does it look for the end of the gzip streams to begin appending. gzopen
1227 will simply append a gzip stream to the existing file.
1228
1229 gzopen can be used to read a file which is not in gzip format; in this
1230 case gzread will directly read from the file without decompression. When
1231 reading, this will be detected automatically by looking for the magic two-
1232 byte gzip header.
1233
1234 gzopen returns NULL if the file could not be opened, if there was
1235 insufficient memory to allocate the gzFile state, or if an invalid mode was
1236 specified (an 'r', 'w', or 'a' was not provided, or '+' was provided).
1237 errno can be checked to determine if the reason gzopen failed was that the
1238 file could not be opened.
1239*/
1240
1241ZEXTERN gzFile ZEXPORT gzdopen OF((int fd, const char *mode));
1242/*
1243 gzdopen associates a gzFile with the file descriptor fd. File descriptors
1244 are obtained from calls like open, dup, creat, pipe or fileno (if the file
1245 has been previously opened with fopen). The mode parameter is as in gzopen.
1246
1247 The next call of gzclose on the returned gzFile will also close the file
1248 descriptor fd, just like fclose(fdopen(fd, mode)) closes the file descriptor
1249 fd. If you want to keep fd open, use fd = dup(fd_keep); gz = gzdopen(fd,
1250 mode);. The duplicated descriptor should be saved to avoid a leak, since
1251 gzdopen does not close fd if it fails. If you are using fileno() to get the
1252 file descriptor from a FILE *, then you will have to use dup() to avoid
1253 double-close()ing the file descriptor. Both gzclose() and fclose() will
1254 close the associated file descriptor, so they need to have different file
1255 descriptors.
1256
1257 gzdopen returns NULL if there was insufficient memory to allocate the
1258 gzFile state, if an invalid mode was specified (an 'r', 'w', or 'a' was not
1259 provided, or '+' was provided), or if fd is -1. The file descriptor is not
1260 used until the next gz* read, write, seek, or close operation, so gzdopen
1261 will not detect if fd is invalid (unless fd is -1).
1262*/
1263
1264ZEXTERN int ZEXPORT gzbuffer OF((gzFile file, unsigned size));
1265/*
1266 Set the internal buffer size used by this library's functions. The
1267 default buffer size is 8192 bytes. This function must be called after
1268 gzopen() or gzdopen(), and before any other calls that read or write the
1269 file. The buffer memory allocation is always deferred to the first read or
1270 write. Two buffers are allocated, either both of the specified size when
1271 writing, or one of the specified size and the other twice that size when
1272 reading. A larger buffer size of, for example, 64K or 128K bytes will
1273 noticeably increase the speed of decompression (reading).
1274
1275 The new buffer size also affects the maximum length for gzprintf().
1276
1277 gzbuffer() returns 0 on success, or -1 on failure, such as being called
1278 too late.
1279*/
1280
1281ZEXTERN int ZEXPORT gzsetparams OF((gzFile file, int level, int strategy));
1282/*
1283 Dynamically update the compression level or strategy. See the description
1284 of deflateInit2 for the meaning of these parameters.
1285
1286 gzsetparams returns Z_OK if success, or Z_STREAM_ERROR if the file was not
1287 opened for writing.
1288*/
1289
1290ZEXTERN int ZEXPORT gzread OF((gzFile file, voidp buf, unsigned len));
1291/*
1292 Reads the given number of uncompressed bytes from the compressed file. If
1293 the input file is not in gzip format, gzread copies the given number of
1294 bytes into the buffer directly from the file.
1295
1296 After reaching the end of a gzip stream in the input, gzread will continue
1297 to read, looking for another gzip stream. Any number of gzip streams may be
1298 concatenated in the input file, and will all be decompressed by gzread().
1299 If something other than a gzip stream is encountered after a gzip stream,
1300 that remaining trailing garbage is ignored (and no error is returned).
1301
1302 gzread can be used to read a gzip file that is being concurrently written.
1303 Upon reaching the end of the input, gzread will return with the available
1304 data. If the error code returned by gzerror is Z_OK or Z_BUF_ERROR, then
1305 gzclearerr can be used to clear the end of file indicator in order to permit
1306 gzread to be tried again. Z_OK indicates that a gzip stream was completed
1307 on the last gzread. Z_BUF_ERROR indicates that the input file ended in the
1308 middle of a gzip stream. Note that gzread does not return -1 in the event
1309 of an incomplete gzip stream. This error is deferred until gzclose(), which
1310 will return Z_BUF_ERROR if the last gzread ended in the middle of a gzip
1311 stream. Alternatively, gzerror can be used before gzclose to detect this
1312 case.
1313
1314 gzread returns the number of uncompressed bytes actually read, less than
1315 len for end of file, or -1 for error.
1316*/
1317
1318ZEXTERN int ZEXPORT gzwrite OF((gzFile file,
1319 voidpc buf, unsigned len));
1320/*
1321 Writes the given number of uncompressed bytes into the compressed file.
1322 gzwrite returns the number of uncompressed bytes written or 0 in case of
1323 error.
1324*/
1325
1326ZEXTERN int ZEXPORTVA gzprintf Z_ARG((gzFile file, const char *format, ...));
1327/*
1328 Converts, formats, and writes the arguments to the compressed file under
1329 control of the format string, as in fprintf. gzprintf returns the number of
1330 uncompressed bytes actually written, or 0 in case of error. The number of
1331 uncompressed bytes written is limited to 8191, or one less than the buffer
1332 size given to gzbuffer(). The caller should assure that this limit is not
1333 exceeded. If it is exceeded, then gzprintf() will return an error (0) with
1334 nothing written. In this case, there may also be a buffer overflow with
1335 unpredictable consequences, which is possible only if zlib was compiled with
1336 the insecure functions sprintf() or vsprintf() because the secure snprintf()
1337 or vsnprintf() functions were not available. This can be determined using
1338 zlibCompileFlags().
1339*/
1340
1341ZEXTERN int ZEXPORT gzputs OF((gzFile file, const char *s));
1342/*
1343 Writes the given null-terminated string to the compressed file, excluding
1344 the terminating null character.
1345
1346 gzputs returns the number of characters written, or -1 in case of error.
1347*/
1348
1349ZEXTERN char * ZEXPORT gzgets OF((gzFile file, char *buf, int len));
1350/*
1351 Reads bytes from the compressed file until len-1 characters are read, or a
1352 newline character is read and transferred to buf, or an end-of-file
1353 condition is encountered. If any characters are read or if len == 1, the
1354 string is terminated with a null character. If no characters are read due
1355 to an end-of-file or len < 1, then the buffer is left untouched.
1356
1357 gzgets returns buf which is a null-terminated string, or it returns NULL
1358 for end-of-file or in case of error. If there was an error, the contents at
1359 buf are indeterminate.
1360*/
1361
1362ZEXTERN int ZEXPORT gzputc OF((gzFile file, int c));
1363/*
1364 Writes c, converted to an unsigned char, into the compressed file. gzputc
1365 returns the value that was written, or -1 in case of error.
1366*/
1367
1368ZEXTERN int ZEXPORT gzgetc OF((gzFile file));
1369/*
1370 Reads one byte from the compressed file. gzgetc returns this byte or -1
1371 in case of end of file or error. This is implemented as a macro for speed.
1372 As such, it does not do all of the checking the other functions do. I.e.
1373 it does not check to see if file is NULL, nor whether the structure file
1374 points to has been clobbered or not.
1375*/
1376
1377ZEXTERN int ZEXPORT gzungetc OF((int c, gzFile file));
1378/*
1379 Push one character back onto the stream to be read as the first character
1380 on the next read. At least one character of push-back is allowed.
1381 gzungetc() returns the character pushed, or -1 on failure. gzungetc() will
1382 fail if c is -1, and may fail if a character has been pushed but not read
1383 yet. If gzungetc is used immediately after gzopen or gzdopen, at least the
1384 output buffer size of pushed characters is allowed. (See gzbuffer above.)
1385 The pushed character will be discarded if the stream is repositioned with
1386 gzseek() or gzrewind().
1387*/
1388
1389ZEXTERN int ZEXPORT gzflush OF((gzFile file, int flush));
1390/*
1391 Flushes all pending output into the compressed file. The parameter flush
1392 is as in the deflate() function. The return value is the zlib error number
1393 (see function gzerror below). gzflush is only permitted when writing.
1394
1395 If the flush parameter is Z_FINISH, the remaining data is written and the
1396 gzip stream is completed in the output. If gzwrite() is called again, a new
1397 gzip stream will be started in the output. gzread() is able to read such
1398 concatented gzip streams.
1399
1400 gzflush should be called only when strictly necessary because it will
1401 degrade compression if called too often.
1402*/
1403
1404/*
1405ZEXTERN z_off_t ZEXPORT gzseek OF((gzFile file,
1406 z_off_t offset, int whence));
1407
1408 Sets the starting position for the next gzread or gzwrite on the given
1409 compressed file. The offset represents a number of bytes in the
1410 uncompressed data stream. The whence parameter is defined as in lseek(2);
1411 the value SEEK_END is not supported.
1412
1413 If the file is opened for reading, this function is emulated but can be
1414 extremely slow. If the file is opened for writing, only forward seeks are
1415 supported; gzseek then compresses a sequence of zeroes up to the new
1416 starting position.
1417
1418 gzseek returns the resulting offset location as measured in bytes from
1419 the beginning of the uncompressed stream, or -1 in case of error, in
1420 particular if the file is opened for writing and the new starting position
1421 would be before the current position.
1422*/
1423
1424ZEXTERN int ZEXPORT gzrewind OF((gzFile file));
1425/*
1426 Rewinds the given file. This function is supported only for reading.
1427
1428 gzrewind(file) is equivalent to (int)gzseek(file, 0L, SEEK_SET)
1429*/
1430
1431/*
1432ZEXTERN z_off_t ZEXPORT gztell OF((gzFile file));
1433
1434 Returns the starting position for the next gzread or gzwrite on the given
1435 compressed file. This position represents a number of bytes in the
1436 uncompressed data stream, and is zero when starting, even if appending or
1437 reading a gzip stream from the middle of a file using gzdopen().
1438
1439 gztell(file) is equivalent to gzseek(file, 0L, SEEK_CUR)
1440*/
1441
1442/*
1443ZEXTERN z_off_t ZEXPORT gzoffset OF((gzFile file));
1444
1445 Returns the current offset in the file being read or written. This offset
1446 includes the count of bytes that precede the gzip stream, for example when
1447 appending or when using gzdopen() for reading. When reading, the offset
1448 does not include as yet unused buffered input. This information can be used
1449 for a progress indicator. On error, gzoffset() returns -1.
1450*/
1451
1452ZEXTERN int ZEXPORT gzeof OF((gzFile file));
1453/*
1454 Returns true (1) if the end-of-file indicator has been set while reading,
1455 false (0) otherwise. Note that the end-of-file indicator is set only if the
1456 read tried to go past the end of the input, but came up short. Therefore,
1457 just like feof(), gzeof() may return false even if there is no more data to
1458 read, in the event that the last read request was for the exact number of
1459 bytes remaining in the input file. This will happen if the input file size
1460 is an exact multiple of the buffer size.
1461
1462 If gzeof() returns true, then the read functions will return no more data,
1463 unless the end-of-file indicator is reset by gzclearerr() and the input file
1464 has grown since the previous end of file was detected.
1465*/
1466
1467ZEXTERN int ZEXPORT gzdirect OF((gzFile file));
1468/*
1469 Returns true (1) if file is being copied directly while reading, or false
1470 (0) if file is a gzip stream being decompressed.
1471
1472 If the input file is empty, gzdirect() will return true, since the input
1473 does not contain a gzip stream.
1474
1475 If gzdirect() is used immediately after gzopen() or gzdopen() it will
1476 cause buffers to be allocated to allow reading the file to determine if it
1477 is a gzip file. Therefore if gzbuffer() is used, it should be called before
1478 gzdirect().
1479
1480 When writing, gzdirect() returns true (1) if transparent writing was
1481 requested ("wT" for the gzopen() mode), or false (0) otherwise. (Note:
1482 gzdirect() is not needed when writing. Transparent writing must be
1483 explicitly requested, so the application already knows the answer. When
1484 linking statically, using gzdirect() will include all of the zlib code for
1485 gzip file reading and decompression, which may not be desired.)
1486*/
1487
1488ZEXTERN int ZEXPORT gzclose OF((gzFile file));
1489/*
1490 Flushes all pending output if necessary, closes the compressed file and
1491 deallocates the (de)compression state. Note that once file is closed, you
1492 cannot call gzerror with file, since its structures have been deallocated.
1493 gzclose must not be called more than once on the same file, just as free
1494 must not be called more than once on the same allocation.
1495
1496 gzclose will return Z_STREAM_ERROR if file is not valid, Z_ERRNO on a
1497 file operation error, Z_MEM_ERROR if out of memory, Z_BUF_ERROR if the
1498 last read ended in the middle of a gzip stream, or Z_OK on success.
1499*/
1500
1501ZEXTERN int ZEXPORT gzclose_r OF((gzFile file));
1502ZEXTERN int ZEXPORT gzclose_w OF((gzFile file));
1503/*
1504 Same as gzclose(), but gzclose_r() is only for use when reading, and
1505 gzclose_w() is only for use when writing or appending. The advantage to
1506 using these instead of gzclose() is that they avoid linking in zlib
1507 compression or decompression code that is not used when only reading or only
1508 writing respectively. If gzclose() is used, then both compression and
1509 decompression code will be included the application when linking to a static
1510 zlib library.
1511*/
1512
1513ZEXTERN const char * ZEXPORT gzerror OF((gzFile file, int *errnum));
1514/*
1515 Returns the error message for the last error which occurred on the given
1516 compressed file. errnum is set to zlib error number. If an error occurred
1517 in the file system and not in the compression library, errnum is set to
1518 Z_ERRNO and the application may consult errno to get the exact error code.
1519
1520 The application must not modify the returned string. Future calls to
1521 this function may invalidate the previously returned string. If file is
1522 closed, then the string previously returned by gzerror will no longer be
1523 available.
1524
1525 gzerror() should be used to distinguish errors from end-of-file for those
1526 functions above that do not distinguish those cases in their return values.
1527*/
1528
1529ZEXTERN void ZEXPORT gzclearerr OF((gzFile file));
1530/*
1531 Clears the error and end-of-file flags for file. This is analogous to the
1532 clearerr() function in stdio. This is useful for continuing to read a gzip
1533 file that is being written concurrently.
1534*/
1535
1536#endif /* !Z_SOLO */
1537
1538 /* checksum functions */
1539
1540/*
1541 These functions are not related to compression but are exported
1542 anyway because they might be useful in applications using the compression
1543 library.
1544*/
1545
1546ZEXTERN uLong ZEXPORT adler32 OF((uLong adler, const Bytef *buf, uInt len));
1547/*
1548 Update a running Adler-32 checksum with the bytes buf[0..len-1] and
1549 return the updated checksum. If buf is Z_NULL, this function returns the
1550 required initial value for the checksum.
1551
1552 An Adler-32 checksum is almost as reliable as a CRC32 but can be computed
1553 much faster.
1554
1555 Usage example:
1556
1557 uLong adler = adler32(0L, Z_NULL, 0);
1558
1559 while (read_buffer(buffer, length) != EOF) {
1560 adler = adler32(adler, buffer, length);
1561 }
1562 if (adler != original_adler) error();
1563*/
1564
1565/*
1566ZEXTERN uLong ZEXPORT adler32_combine OF((uLong adler1, uLong adler2,
1567 z_off_t len2));
1568
1569 Combine two Adler-32 checksums into one. For two sequences of bytes, seq1
1570 and seq2 with lengths len1 and len2, Adler-32 checksums were calculated for
1571 each, adler1 and adler2. adler32_combine() returns the Adler-32 checksum of
1572 seq1 and seq2 concatenated, requiring only adler1, adler2, and len2. Note
1573 that the z_off_t type (like off_t) is a signed integer. If len2 is
1574 negative, the result has no meaning or utility.
1575*/
1576
1577ZEXTERN uLong ZEXPORT crc32 OF((uLong crc, const Bytef *buf, uInt len));
1578/*
1579 Update a running CRC-32 with the bytes buf[0..len-1] and return the
1580 updated CRC-32. If buf is Z_NULL, this function returns the required
1581 initial value for the for the crc. Pre- and post-conditioning (one's
1582 complement) is performed within this function so it shouldn't be done by the
1583 application.
1584
1585 Usage example:
1586
1587 uLong crc = crc32(0L, Z_NULL, 0);
1588
1589 while (read_buffer(buffer, length) != EOF) {
1590 crc = crc32(crc, buffer, length);
1591 }
1592 if (crc != original_crc) error();
1593*/
1594
1595/*
1596ZEXTERN uLong ZEXPORT crc32_combine OF((uLong crc1, uLong crc2, z_off_t len2));
1597
1598 Combine two CRC-32 check values into one. For two sequences of bytes,
1599 seq1 and seq2 with lengths len1 and len2, CRC-32 check values were
1600 calculated for each, crc1 and crc2. crc32_combine() returns the CRC-32
1601 check value of seq1 and seq2 concatenated, requiring only crc1, crc2, and
1602 len2.
1603*/
1604
1605
1606 /* various hacks, don't look :) */
1607
1608/* deflateInit and inflateInit are macros to allow checking the zlib version
1609 * and the compiler's view of z_stream:
1610 */
1611ZEXTERN int ZEXPORT deflateInit_ OF((z_streamp strm, int level,
1612 const char *version, int stream_size));
1613ZEXTERN int ZEXPORT inflateInit_ OF((z_streamp strm,
1614 const char *version, int stream_size));
1615ZEXTERN int ZEXPORT deflateInit2_ OF((z_streamp strm, int level, int method,
1616 int windowBits, int memLevel,
1617 int strategy, const char *version,
1618 int stream_size));
1619ZEXTERN int ZEXPORT inflateInit2_ OF((z_streamp strm, int windowBits,
1620 const char *version, int stream_size));
1621ZEXTERN int ZEXPORT inflateBackInit_ OF((z_streamp strm, int windowBits,
1622 unsigned char FAR *window,
1623 const char *version,
1624 int stream_size));
1625#define deflateInit(strm, level) \
1626 deflateInit_((strm), (level), ZLIB_VERSION, (int)sizeof(z_stream))
1627#define inflateInit(strm) \
1628 inflateInit_((strm), ZLIB_VERSION, (int)sizeof(z_stream))
1629#define deflateInit2(strm, level, method, windowBits, memLevel, strategy) \
1630 deflateInit2_((strm),(level),(method),(windowBits),(memLevel),\
1631 (strategy), ZLIB_VERSION, (int)sizeof(z_stream))
1632#define inflateInit2(strm, windowBits) \
1633 inflateInit2_((strm), (windowBits), ZLIB_VERSION, \
1634 (int)sizeof(z_stream))
1635#define inflateBackInit(strm, windowBits, window) \
1636 inflateBackInit_((strm), (windowBits), (window), \
1637 ZLIB_VERSION, (int)sizeof(z_stream))
1638
1639#ifndef Z_SOLO
1640
1641/* gzgetc() macro and its supporting function and exposed data structure. Note
1642 * that the real internal state is much larger than the exposed structure.
1643 * This abbreviated structure exposes just enough for the gzgetc() macro. The
1644 * user should not mess with these exposed elements, since their names or
1645 * behavior could change in the future, perhaps even capriciously. They can
1646 * only be used by the gzgetc() macro. You have been warned.
1647 */
1648struct gzFile_s {
1649 unsigned have;
1650 unsigned char *next;
1651 z_off64_t pos;
1652};
1653ZEXTERN int ZEXPORT gzgetc_ OF((gzFile file));
1654#define gzgetc(g) \
1655 ((g)->have ? ((g)->have--, (g)->pos++, *((g)->next)++) : gzgetc_(g))
1656
1657/* provide 64-bit offset functions if _LARGEFILE64_SOURCE defined, and/or
1658 * change the regular functions to 64 bits if _FILE_OFFSET_BITS is 64 (if
1659 * both are true, the application gets the *64 functions, and the regular
1660 * functions are changed to 64 bits) -- in case these are set on systems
1661 * without large file support, _LFS64_LARGEFILE must also be true
1662 */
1663#if defined(_LARGEFILE64_SOURCE) && _LFS64_LARGEFILE-0
1664 ZEXTERN gzFile ZEXPORT gzopen64 OF((const char *, const char *));
1665 ZEXTERN z_off64_t ZEXPORT gzseek64 OF((gzFile, z_off64_t, int));
1666 ZEXTERN z_off64_t ZEXPORT gztell64 OF((gzFile));
1667 ZEXTERN z_off64_t ZEXPORT gzoffset64 OF((gzFile));
1668 ZEXTERN uLong ZEXPORT adler32_combine64 OF((uLong, uLong, z_off64_t));
1669 ZEXTERN uLong ZEXPORT crc32_combine64 OF((uLong, uLong, z_off64_t));
1670#endif
1671
1672#if !defined(ZLIB_INTERNAL) && _FILE_OFFSET_BITS-0 == 64 && _LFS64_LARGEFILE-0
1673# if defined(VBOX)
1674# define vboxzlib_gzopen vboxzlib_gzopen64
1675# define vboxzlib_gzseek vboxzlib_gzseek64
1676# define vboxzlib_gztell vboxzlib_gztell64
1677# define vboxzlib_gzoffset vboxzlib_gzoffset64
1678# define vboxzlib_adler32_combine vboxzlib_adler32_combine64
1679# define vboxzlib_crc32_combine vboxzlib_crc32_combine64
1680# elif defined(Z_PREFIX_SET)
1681# define z_gzopen z_gzopen64
1682# define z_gzseek z_gzseek64
1683# define z_gztell z_gztell64
1684# define z_gzoffset z_gzoffset64
1685# define z_adler32_combine z_adler32_combine64
1686# define z_crc32_combine z_crc32_combine64
1687# else
1688# define gzopen gzopen64
1689# define gzseek gzseek64
1690# define gztell gztell64
1691# define gzoffset gzoffset64
1692# define adler32_combine adler32_combine64
1693# define crc32_combine crc32_combine64
1694# endif
1695# ifndef _LARGEFILE64_SOURCE
1696 ZEXTERN gzFile ZEXPORT gzopen64 OF((const char *, const char *));
1697 ZEXTERN z_off_t ZEXPORT gzseek64 OF((gzFile, z_off_t, int));
1698 ZEXTERN z_off_t ZEXPORT gztell64 OF((gzFile));
1699 ZEXTERN z_off_t ZEXPORT gzoffset64 OF((gzFile));
1700 ZEXTERN uLong ZEXPORT adler32_combine64 OF((uLong, uLong, z_off_t));
1701 ZEXTERN uLong ZEXPORT crc32_combine64 OF((uLong, uLong, z_off_t));
1702# endif
1703#else
1704 ZEXTERN gzFile ZEXPORT gzopen OF((const char *, const char *));
1705 ZEXTERN z_off_t ZEXPORT gzseek OF((gzFile, z_off_t, int));
1706 ZEXTERN z_off_t ZEXPORT gztell OF((gzFile));
1707 ZEXTERN z_off_t ZEXPORT gzoffset OF((gzFile));
1708 ZEXTERN uLong ZEXPORT adler32_combine OF((uLong, uLong, z_off_t));
1709 ZEXTERN uLong ZEXPORT crc32_combine OF((uLong, uLong, z_off_t));
1710#endif
1711
1712#else /* Z_SOLO */
1713
1714 ZEXTERN uLong ZEXPORT adler32_combine OF((uLong, uLong, z_off_t));
1715 ZEXTERN uLong ZEXPORT crc32_combine OF((uLong, uLong, z_off_t));
1716
1717#endif /* !Z_SOLO */
1718
1719/* hack for buggy compilers */
1720#if !defined(ZUTIL_H) && !defined(NO_DUMMY_DECL)
1721 struct internal_state {int dummy;};
1722#endif
1723
1724/* undocumented functions */
1725ZEXTERN const char * ZEXPORT zError OF((int));
1726ZEXTERN int ZEXPORT inflateSyncPoint OF((z_streamp));
1727ZEXTERN const uLongf * ZEXPORT get_crc_table OF((void));
1728ZEXTERN int ZEXPORT inflateUndermine OF((z_streamp, int));
1729ZEXTERN int ZEXPORT inflateResetKeep OF((z_streamp));
1730ZEXTERN int ZEXPORT deflateResetKeep OF((z_streamp));
1731#ifndef Z_SOLO
1732 ZEXTERN unsigned long ZEXPORT gzflags OF((void));
1733#endif
1734
1735#ifdef __cplusplus
1736}
1737#endif
1738
1739#endif /* ZLIB_H */
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