openshot-audio  0.1.6
zlib.h
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1 /* zlib.h -- interface of the 'zlib' general purpose compression library
2  version 1.2.3, July 18th, 2005
3 
4  Copyright (C) 1995-2005 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  jloup@gzip.org madler@alumni.caltech.edu
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://www.ietf.org/rfc/rfc1950.txt
28  (zlib format), rfc1951.txt (deflate format) and rfc1952.txt (gzip format).
29 */
30 
31 #ifndef ZLIB_H
32 #define ZLIB_H
33 
34 #include "zconf.h"
35 
36 #ifdef __cplusplus
37 //extern "C" {
38 #endif
39 
40 #define ZLIB_VERSION "1.2.3"
41 #define ZLIB_VERNUM 0x1230
42 
43 
44 /*
45  The 'zlib' compression library provides in-memory compression and
46  decompression functions, including integrity checks of the uncompressed
47  data. This version of the library supports only one compression method
48  (deflation) but other algorithms will be added later and will have the same
49  stream interface.
50 
51  Compression can be done in a single step if the buffers are large
52  enough (for example if an input file is mmap'ed), or can be done by
53  repeated calls of the compression function. In the latter case, the
54  application must provide more input and/or consume the output
55  (providing more output space) before each call.
56 
57  The compressed data format used by default by the in-memory functions is
58  the zlib format, which is a zlib wrapper documented in RFC 1950, wrapped
59  around a deflate stream, which is itself documented in RFC 1951.
60 
61  The library also supports reading and writing files in gzip (.gz) format
62  with an interface similar to that of stdio using the functions that start
63  with "gz". The gzip format is different from the zlib format. gzip is a
64  gzip wrapper, documented in RFC 1952, wrapped around a deflate stream.
65 
66  This library can optionally read and write gzip streams in memory as well.
67 
68  The zlib format was designed to be compact and fast for use in memory
69  and on communications channels. The gzip format was designed for single-
70  file compression on file systems, has a larger header than zlib to maintain
71  directory information, and uses a different, slower check method than zlib.
72 
73  The library does not install any signal handler. The decoder checks
74  the consistency of the compressed data, so the library should never
75  crash even in case of corrupted input.
76 */
77 
78 typedef voidpf (*alloc_func) OF((voidpf opaque, uInt items, uInt size));
79 typedef void (*free_func) OF((voidpf opaque, voidpf address));
80 
81 struct internal_state;
82 
83 typedef struct z_stream_s {
84  Bytef *next_in; /* next input byte */
85  uInt avail_in; /* number of bytes available at next_in */
86  uLong total_in; /* total nb of input bytes read so far */
87 
88  Bytef *next_out; /* next output byte should be put there */
89  uInt avail_out; /* remaining free space at next_out */
90  uLong total_out; /* total nb of bytes output so far */
91 
92  char *msg; /* last error message, NULL if no error */
93  struct internal_state FAR *state; /* not visible by applications */
94 
95  alloc_func zalloc; /* used to allocate the internal state */
96  free_func zfree; /* used to free the internal state */
97  voidpf opaque; /* private data object passed to zalloc and zfree */
98 
99  int data_type; /* best guess about the data type: binary or text */
100  uLong adler; /* adler32 value of the uncompressed data */
101  uLong reserved; /* reserved for future use */
102 } z_stream;
103 
105 
106 /*
107  gzip header information passed to and from zlib routines. See RFC 1952
108  for more details on the meanings of these fields.
109 */
110 typedef struct gz_header_s {
111  int text; /* true if compressed data believed to be text */
112  uLong time; /* modification time */
113  int xflags; /* extra flags (not used when writing a gzip file) */
114  int os; /* operating system */
115  Bytef *extra; /* pointer to extra field or Z_NULL if none */
116  uInt extra_len; /* extra field length (valid if extra != Z_NULL) */
117  uInt extra_max; /* space at extra (only when reading header) */
118  Bytef *name; /* pointer to zero-terminated file name or Z_NULL */
119  uInt name_max; /* space at name (only when reading header) */
120  Bytef *comment; /* pointer to zero-terminated comment or Z_NULL */
121  uInt comm_max; /* space at comment (only when reading header) */
122  int hcrc; /* true if there was or will be a header crc */
123  int done; /* true when done reading gzip header (not used
124  when writing a gzip file) */
125 } gz_header;
126 
128 
129 /*
130  The application must update next_in and avail_in when avail_in has
131  dropped to zero. It must update next_out and avail_out when avail_out
132  has dropped to zero. The application must initialize zalloc, zfree and
133  opaque before calling the init function. All other fields are set by the
134  compression library and must not be updated by the application.
135 
136  The opaque value provided by the application will be passed as the first
137  parameter for calls of zalloc and zfree. This can be useful for custom
138  memory management. The compression library attaches no meaning to the
139  opaque value.
140 
141  zalloc must return Z_NULL if there is not enough memory for the object.
142  If zlib is used in a multi-threaded application, zalloc and zfree must be
143  thread safe.
144 
145  On 16-bit systems, the functions zalloc and zfree must be able to allocate
146  exactly 65536 bytes, but will not be required to allocate more than this
147  if the symbol MAXSEG_64K is defined (see zconf.h). WARNING: On MSDOS,
148  pointers returned by zalloc for objects of exactly 65536 bytes *must*
149  have their offset normalized to zero. The default allocation function
150  provided by this library ensures this (see zutil.c). To reduce memory
151  requirements and avoid any allocation of 64K objects, at the expense of
152  compression ratio, compile the library with -DMAX_WBITS=14 (see zconf.h).
153 
154  The fields total_in and total_out can be used for statistics or
155  progress reports. After compression, total_in holds the total size of
156  the uncompressed data and may be saved for use in the decompressor
157  (particularly if the decompressor wants to decompress everything in
158  a single step).
159 */
160 
161  /* constants */
162 
163 #define Z_NO_FLUSH 0
164 #define Z_PARTIAL_FLUSH 1 /* will be removed, use Z_SYNC_FLUSH instead */
165 #define Z_SYNC_FLUSH 2
166 #define Z_FULL_FLUSH 3
167 #define Z_FINISH 4
168 #define Z_BLOCK 5
169 /* Allowed flush values; see deflate() and inflate() below for details */
170 
171 #define Z_OK 0
172 #define Z_STREAM_END 1
173 #define Z_NEED_DICT 2
174 #define Z_ERRNO (-1)
175 #define Z_STREAM_ERROR (-2)
176 #define Z_DATA_ERROR (-3)
177 #define Z_MEM_ERROR (-4)
178 #define Z_BUF_ERROR (-5)
179 #define Z_VERSION_ERROR (-6)
180 /* Return codes for the compression/decompression functions. Negative
181  * values are errors, positive values are used for special but normal events.
182  */
183 
184 #define Z_NO_COMPRESSION 0
185 #define Z_BEST_SPEED 1
186 #define Z_BEST_COMPRESSION 9
187 #define Z_DEFAULT_COMPRESSION (-1)
188 /* compression levels */
189 
190 #define Z_FILTERED 1
191 #define Z_HUFFMAN_ONLY 2
192 #define Z_RLE 3
193 #define Z_FIXED 4
194 #define Z_DEFAULT_STRATEGY 0
195 /* compression strategy; see deflateInit2() below for details */
196 
197 #define Z_BINARY 0
198 #define Z_TEXT 1
199 #define Z_ASCII Z_TEXT /* for compatibility with 1.2.2 and earlier */
200 #define Z_UNKNOWN 2
201 /* Possible values of the data_type field (though see inflate()) */
202 
203 #define Z_DEFLATED 8
204 /* The deflate compression method (the only one supported in this version) */
205 
206 #define Z_NULL 0 /* for initializing zalloc, zfree, opaque */
207 
208 #define zlib_version zlibVersion()
209 /* for compatibility with versions < 1.0.2 */
210 
211  /* basic functions */
212 
213 //ZEXTERN const char * ZEXPORT zlibVersion OF((void));
214 /* The application can compare zlibVersion and ZLIB_VERSION for consistency.
215  If the first character differs, the library code actually used is
216  not compatible with the zlib.h header file used by the application.
217  This check is automatically made by deflateInit and inflateInit.
218  */
219 
220 /*
221 ZEXTERN int ZEXPORT deflateInit OF((z_streamp strm, int level));
222 
223  Initializes the internal stream state for compression. The fields
224  zalloc, zfree and opaque must be initialized before by the caller.
225  If zalloc and zfree are set to Z_NULL, deflateInit updates them to
226  use default allocation functions.
227 
228  The compression level must be Z_DEFAULT_COMPRESSION, or between 0 and 9:
229  1 gives best speed, 9 gives best compression, 0 gives no compression at
230  all (the input data is simply copied a block at a time).
231  Z_DEFAULT_COMPRESSION requests a default compromise between speed and
232  compression (currently equivalent to level 6).
233 
234  deflateInit returns Z_OK if success, Z_MEM_ERROR if there was not
235  enough memory, Z_STREAM_ERROR if level is not a valid compression level,
236  Z_VERSION_ERROR if the zlib library version (zlib_version) is incompatible
237  with the version assumed by the caller (ZLIB_VERSION).
238  msg is set to null if there is no error message. deflateInit does not
239  perform any compression: this will be done by deflate().
240 */
241 
242 
243 ZEXTERN int ZEXPORT deflate OF((z_streamp strm, int flush));
244 /*
245  deflate compresses as much data as possible, and stops when the input
246  buffer becomes empty or the output buffer becomes full. It may introduce some
247  output latency (reading input without producing any output) except when
248  forced to flush.
249 
250  The detailed semantics are as follows. deflate performs one or both of the
251  following actions:
252 
253  - Compress more input starting at next_in and update next_in and avail_in
254  accordingly. If not all input can be processed (because there is not
255  enough room in the output buffer), next_in and avail_in are updated and
256  processing will resume at this point for the next call of deflate().
257 
258  - Provide more output starting at next_out and update next_out and avail_out
259  accordingly. This action is forced if the parameter flush is non zero.
260  Forcing flush frequently degrades the compression ratio, so this parameter
261  should be set only when necessary (in interactive applications).
262  Some output may be provided even if flush is not set.
263 
264  Before the call of deflate(), the application should ensure that at least
265  one of the actions is possible, by providing more input and/or consuming
266  more output, and updating avail_in or avail_out accordingly; avail_out
267  should never be zero before the call. The application can consume the
268  compressed output when it wants, for example when the output buffer is full
269  (avail_out == 0), or after each call of deflate(). If deflate returns Z_OK
270  and with zero avail_out, it must be called again after making room in the
271  output buffer because there might be more output pending.
272 
273  Normally the parameter flush is set to Z_NO_FLUSH, which allows deflate to
274  decide how much data to accumualte before producing output, in order to
275  maximize compression.
276 
277  If the parameter flush is set to Z_SYNC_FLUSH, all pending output is
278  flushed to the output buffer and the output is aligned on a byte boundary, so
279  that the decompressor can get all input data available so far. (In particular
280  avail_in is zero after the call if enough output space has been provided
281  before the call.) Flushing may degrade compression for some compression
282  algorithms and so it should be used only when necessary.
283 
284  If flush is set to Z_FULL_FLUSH, all output is flushed as with
285  Z_SYNC_FLUSH, and the compression state is reset so that decompression can
286  restart from this point if previous compressed data has been damaged or if
287  random access is desired. Using Z_FULL_FLUSH too often can seriously degrade
288  compression.
289 
290  If deflate returns with avail_out == 0, this function must be called again
291  with the same value of the flush parameter and more output space (updated
292  avail_out), until the flush is complete (deflate returns with non-zero
293  avail_out). In the case of a Z_FULL_FLUSH or Z_SYNC_FLUSH, make sure that
294  avail_out is greater than six to avoid repeated flush markers due to
295  avail_out == 0 on return.
296 
297  If the parameter flush is set to Z_FINISH, pending input is processed,
298  pending output is flushed and deflate returns with Z_STREAM_END if there
299  was enough output space; if deflate returns with Z_OK, this function must be
300  called again with Z_FINISH and more output space (updated avail_out) but no
301  more input data, until it returns with Z_STREAM_END or an error. After
302  deflate has returned Z_STREAM_END, the only possible operations on the
303  stream are deflateReset or deflateEnd.
304 
305  Z_FINISH can be used immediately after deflateInit if all the compression
306  is to be done in a single step. In this case, avail_out must be at least
307  the value returned by deflateBound (see below). If deflate does not return
308  Z_STREAM_END, then it must be called again as described above.
309 
310  deflate() sets strm->adler to the adler32 checksum of all input read
311  so far (that is, total_in bytes).
312 
313  deflate() may update strm->data_type if it can make a good guess about
314  the input data type (Z_BINARY or Z_TEXT). In doubt, the data is considered
315  binary. This field is only for information purposes and does not affect
316  the compression algorithm in any manner.
317 
318  deflate() returns Z_OK if some progress has been made (more input
319  processed or more output produced), Z_STREAM_END if all input has been
320  consumed and all output has been produced (only when flush is set to
321  Z_FINISH), Z_STREAM_ERROR if the stream state was inconsistent (for example
322  if next_in or next_out was NULL), Z_BUF_ERROR if no progress is possible
323  (for example avail_in or avail_out was zero). Note that Z_BUF_ERROR is not
324  fatal, and deflate() can be called again with more input and more output
325  space to continue compressing.
326 */
327 
328 
330 /*
331  All dynamically allocated data structures for this stream are freed.
332  This function discards any unprocessed input and does not flush any
333  pending output.
334 
335  deflateEnd returns Z_OK if success, Z_STREAM_ERROR if the
336  stream state was inconsistent, Z_DATA_ERROR if the stream was freed
337  prematurely (some input or output was discarded). In the error case,
338  msg may be set but then points to a static string (which must not be
339  deallocated).
340 */
341 
342 
343 /*
344 ZEXTERN int ZEXPORT inflateInit OF((z_streamp strm));
345 
346  Initializes the internal stream state for decompression. The fields
347  next_in, avail_in, zalloc, zfree and opaque must be initialized before by
348  the caller. If next_in is not Z_NULL and avail_in is large enough (the exact
349  value depends on the compression method), inflateInit determines the
350  compression method from the zlib header and allocates all data structures
351  accordingly; otherwise the allocation will be deferred to the first call of
352  inflate. If zalloc and zfree are set to Z_NULL, inflateInit updates them to
353  use default allocation functions.
354 
355  inflateInit returns Z_OK if success, Z_MEM_ERROR if there was not enough
356  memory, Z_VERSION_ERROR if the zlib library version is incompatible with the
357  version assumed by the caller. msg is set to null if there is no error
358  message. inflateInit does not perform any decompression apart from reading
359  the zlib header if present: this will be done by inflate(). (So next_in and
360  avail_in may be modified, but next_out and avail_out are unchanged.)
361 */
362 
363 
364 ZEXTERN int ZEXPORT inflate OF((z_streamp strm, int flush));
365 /*
366  inflate decompresses as much data as possible, and stops when the input
367  buffer becomes empty or the output buffer becomes full. It may introduce
368  some output latency (reading input without producing any output) except when
369  forced to flush.
370 
371  The detailed semantics are as follows. inflate performs one or both of the
372  following actions:
373 
374  - Decompress more input starting at next_in and update next_in and avail_in
375  accordingly. If not all input can be processed (because there is not
376  enough room in the output buffer), next_in is updated and processing
377  will resume at this point for the next call of inflate().
378 
379  - Provide more output starting at next_out and update next_out and avail_out
380  accordingly. inflate() provides as much output as possible, until there
381  is no more input data or no more space in the output buffer (see below
382  about the flush parameter).
383 
384  Before the call of inflate(), the application should ensure that at least
385  one of the actions is possible, by providing more input and/or consuming
386  more output, and updating the next_* and avail_* values accordingly.
387  The application can consume the uncompressed output when it wants, for
388  example when the output buffer is full (avail_out == 0), or after each
389  call of inflate(). If inflate returns Z_OK and with zero avail_out, it
390  must be called again after making room in the output buffer because there
391  might be more output pending.
392 
393  The flush parameter of inflate() can be Z_NO_FLUSH, Z_SYNC_FLUSH,
394  Z_FINISH, or Z_BLOCK. Z_SYNC_FLUSH requests that inflate() flush as much
395  output as possible to the output buffer. Z_BLOCK requests that inflate() stop
396  if and when it gets to the next deflate block boundary. When decoding the
397  zlib or gzip format, this will cause inflate() to return immediately after
398  the header and before the first block. When doing a raw inflate, inflate()
399  will go ahead and process the first block, and will return when it gets to
400  the end of that block, or when it runs out of data.
401 
402  The Z_BLOCK option assists in appending to or combining deflate streams.
403  Also to assist in this, on return inflate() will set strm->data_type to the
404  number of unused bits in the last byte taken from strm->next_in, plus 64
405  if inflate() is currently decoding the last block in the deflate stream,
406  plus 128 if inflate() returned immediately after decoding an end-of-block
407  code or decoding the complete header up to just before the first byte of the
408  deflate stream. The end-of-block will not be indicated until all of the
409  uncompressed data from that block has been written to strm->next_out. The
410  number of unused bits may in general be greater than seven, except when
411  bit 7 of data_type is set, in which case the number of unused bits will be
412  less than eight.
413 
414  inflate() should normally be called until it returns Z_STREAM_END or an
415  error. However if all decompression is to be performed in a single step
416  (a single call of inflate), the parameter flush should be set to
417  Z_FINISH. In this case all pending input is processed and all pending
418  output is flushed; avail_out must be large enough to hold all the
419  uncompressed data. (The size of the uncompressed data may have been saved
420  by the compressor for this purpose.) The next operation on this stream must
421  be inflateEnd to deallocate the decompression state. The use of Z_FINISH
422  is never required, but can be used to inform inflate that a faster approach
423  may be used for the single inflate() call.
424 
425  In this implementation, inflate() always flushes as much output as
426  possible to the output buffer, and always uses the faster approach on the
427  first call. So the only effect of the flush parameter in this implementation
428  is on the return value of inflate(), as noted below, or when it returns early
429  because Z_BLOCK is used.
430 
431  If a preset dictionary is needed after this call (see inflateSetDictionary
432  below), inflate sets strm->adler to the adler32 checksum of the dictionary
433  chosen by the compressor and returns Z_NEED_DICT; otherwise it sets
434  strm->adler to the adler32 checksum of all output produced so far (that is,
435  total_out bytes) and returns Z_OK, Z_STREAM_END or an error code as described
436  below. At the end of the stream, inflate() checks that its computed adler32
437  checksum is equal to that saved by the compressor and returns Z_STREAM_END
438  only if the checksum is correct.
439 
440  inflate() will decompress and check either zlib-wrapped or gzip-wrapped
441  deflate data. The header type is detected automatically. Any information
442  contained in the gzip header is not retained, so applications that need that
443  information should instead use raw inflate, see inflateInit2() below, or
444  inflateBack() and perform their own processing of the gzip header and
445  trailer.
446 
447  inflate() returns Z_OK if some progress has been made (more input processed
448  or more output produced), Z_STREAM_END if the end of the compressed data has
449  been reached and all uncompressed output has been produced, Z_NEED_DICT if a
450  preset dictionary is needed at this point, Z_DATA_ERROR if the input data was
451  corrupted (input stream not conforming to the zlib format or incorrect check
452  value), Z_STREAM_ERROR if the stream structure was inconsistent (for example
453  if next_in or next_out was NULL), Z_MEM_ERROR if there was not enough memory,
454  Z_BUF_ERROR if no progress is possible or if there was not enough room in the
455  output buffer when Z_FINISH is used. Note that Z_BUF_ERROR is not fatal, and
456  inflate() can be called again with more input and more output space to
457  continue decompressing. If Z_DATA_ERROR is returned, the application may then
458  call inflateSync() to look for a good compression block if a partial recovery
459  of the data is desired.
460 */
461 
462 
464 /*
465  All dynamically allocated data structures for this stream are freed.
466  This function discards any unprocessed input and does not flush any
467  pending output.
468 
469  inflateEnd returns Z_OK if success, Z_STREAM_ERROR if the stream state
470  was inconsistent. In the error case, msg may be set but then points to a
471  static string (which must not be deallocated).
472 */
473 
474  /* Advanced functions */
475 
476 /*
477  The following functions are needed only in some special applications.
478 */
479 
480 /*
481 ZEXTERN int ZEXPORT deflateInit2 OF((z_streamp strm,
482  int level,
483  int method,
484  int windowBits,
485  int memLevel,
486  int strategy));
487 
488  This is another version of deflateInit with more compression options. The
489  fields next_in, zalloc, zfree and opaque must be initialized before by
490  the caller.
491 
492  The method parameter is the compression method. It must be Z_DEFLATED in
493  this version of the library.
494 
495  The windowBits parameter is the base two logarithm of the window size
496  (the size of the history buffer). It should be in the range 8..15 for this
497  version of the library. Larger values of this parameter result in better
498  compression at the expense of memory usage. The default value is 15 if
499  deflateInit is used instead.
500 
501  windowBits can also be -8..-15 for raw deflate. In this case, -windowBits
502  determines the window size. deflate() will then generate raw deflate data
503  with no zlib header or trailer, and will not compute an adler32 check value.
504 
505  windowBits can also be greater than 15 for optional gzip encoding. Add
506  16 to windowBits to write a simple gzip header and trailer around the
507  compressed data instead of a zlib wrapper. The gzip header will have no
508  file name, no extra data, no comment, no modification time (set to zero),
509  no header crc, and the operating system will be set to 255 (unknown). If a
510  gzip stream is being written, strm->adler is a crc32 instead of an adler32.
511 
512  The memLevel parameter specifies how much memory should be allocated
513  for the internal compression state. memLevel=1 uses minimum memory but
514  is slow and reduces compression ratio; memLevel=9 uses maximum memory
515  for optimal speed. The default value is 8. See zconf.h for total memory
516  usage as a function of windowBits and memLevel.
517 
518  The strategy parameter is used to tune the compression algorithm. Use the
519  value Z_DEFAULT_STRATEGY for normal data, Z_FILTERED for data produced by a
520  filter (or predictor), Z_HUFFMAN_ONLY to force Huffman encoding only (no
521  string match), or Z_RLE to limit match distances to one (run-length
522  encoding). Filtered data consists mostly of small values with a somewhat
523  random distribution. In this case, the compression algorithm is tuned to
524  compress them better. The effect of Z_FILTERED is to force more Huffman
525  coding and less string matching; it is somewhat intermediate between
526  Z_DEFAULT and Z_HUFFMAN_ONLY. Z_RLE is designed to be almost as fast as
527  Z_HUFFMAN_ONLY, but give better compression for PNG image data. The strategy
528  parameter only affects the compression ratio but not the correctness of the
529  compressed output even if it is not set appropriately. Z_FIXED prevents the
530  use of dynamic Huffman codes, allowing for a simpler decoder for special
531  applications.
532 
533  deflateInit2 returns Z_OK if success, Z_MEM_ERROR if there was not enough
534  memory, Z_STREAM_ERROR if a parameter is invalid (such as an invalid
535  method). msg is set to null if there is no error message. deflateInit2 does
536  not perform any compression: this will be done by deflate().
537 */
538 
540  const Bytef *dictionary,
541  uInt dictLength));
542 /*
543  Initializes the compression dictionary from the given byte sequence
544  without producing any compressed output. This function must be called
545  immediately after deflateInit, deflateInit2 or deflateReset, before any
546  call of deflate. The compressor and decompressor must use exactly the same
547  dictionary (see inflateSetDictionary).
548 
549  The dictionary should consist of strings (byte sequences) that are likely
550  to be encountered later in the data to be compressed, with the most commonly
551  used strings preferably put towards the end of the dictionary. Using a
552  dictionary is most useful when the data to be compressed is short and can be
553  predicted with good accuracy; the data can then be compressed better than
554  with the default empty dictionary.
555 
556  Depending on the size of the compression data structures selected by
557  deflateInit or deflateInit2, a part of the dictionary may in effect be
558  discarded, for example if the dictionary is larger than the window size in
559  deflate or deflate2. Thus the strings most likely to be useful should be
560  put at the end of the dictionary, not at the front. In addition, the
561  current implementation of deflate will use at most the window size minus
562  262 bytes of the provided dictionary.
563 
564  Upon return of this function, strm->adler is set to the adler32 value
565  of the dictionary; the decompressor may later use this value to determine
566  which dictionary has been used by the compressor. (The adler32 value
567  applies to the whole dictionary even if only a subset of the dictionary is
568  actually used by the compressor.) If a raw deflate was requested, then the
569  adler32 value is not computed and strm->adler is not set.
570 
571  deflateSetDictionary returns Z_OK if success, or Z_STREAM_ERROR if a
572  parameter is invalid (such as NULL dictionary) or the stream state is
573  inconsistent (for example if deflate has already been called for this stream
574  or if the compression method is bsort). deflateSetDictionary does not
575  perform any compression: this will be done by deflate().
576 */
577 
579  z_streamp source));
580 /*
581  Sets the destination stream as a complete copy of the source stream.
582 
583  This function can be useful when several compression strategies will be
584  tried, for example when there are several ways of pre-processing the input
585  data with a filter. The streams that will be discarded should then be freed
586  by calling deflateEnd. Note that deflateCopy duplicates the internal
587  compression state which can be quite large, so this strategy is slow and
588  can consume lots of memory.
589 
590  deflateCopy returns Z_OK if success, Z_MEM_ERROR if there was not
591  enough memory, Z_STREAM_ERROR if the source stream state was inconsistent
592  (such as zalloc being NULL). msg is left unchanged in both source and
593  destination.
594 */
595 
597 /*
598  This function is equivalent to deflateEnd followed by deflateInit,
599  but does not free and reallocate all the internal compression state.
600  The stream will keep the same compression level and any other attributes
601  that may have been set by deflateInit2.
602 
603  deflateReset returns Z_OK if success, or Z_STREAM_ERROR if the source
604  stream state was inconsistent (such as zalloc or state being NULL).
605 */
606 
608  int level,
609  int strategy));
610 /*
611  Dynamically update the compression level and compression strategy. The
612  interpretation of level and strategy is as in deflateInit2. This can be
613  used to switch between compression and straight copy of the input data, or
614  to switch to a different kind of input data requiring a different
615  strategy. If the compression level is changed, the input available so far
616  is compressed with the old level (and may be flushed); the new level will
617  take effect only at the next call of deflate().
618 
619  Before the call of deflateParams, the stream state must be set as for
620  a call of deflate(), since the currently available input may have to
621  be compressed and flushed. In particular, strm->avail_out must be non-zero.
622 
623  deflateParams returns Z_OK if success, Z_STREAM_ERROR if the source
624  stream state was inconsistent or if a parameter was invalid, Z_BUF_ERROR
625  if strm->avail_out was zero.
626 */
627 
629  int good_length,
630  int max_lazy,
631  int nice_length,
632  int max_chain));
633 /*
634  Fine tune deflate's internal compression parameters. This should only be
635  used by someone who understands the algorithm used by zlib's deflate for
636  searching for the best matching string, and even then only by the most
637  fanatic optimizer trying to squeeze out the last compressed bit for their
638  specific input data. Read the deflate.c source code for the meaning of the
639  max_lazy, good_length, nice_length, and max_chain parameters.
640 
641  deflateTune() can be called after deflateInit() or deflateInit2(), and
642  returns Z_OK on success, or Z_STREAM_ERROR for an invalid deflate stream.
643  */
644 
646  uLong sourceLen));
647 /*
648  deflateBound() returns an upper bound on the compressed size after
649  deflation of sourceLen bytes. It must be called after deflateInit()
650  or deflateInit2(). This would be used to allocate an output buffer
651  for deflation in a single pass, and so would be called before deflate().
652 */
653 
655  int bits,
656  int value));
657 /*
658  deflatePrime() inserts bits in the deflate output stream. The intent
659  is that this function is used to start off the deflate output with the
660  bits leftover from a previous deflate stream when appending to it. As such,
661  this function can only be used for raw deflate, and must be used before the
662  first deflate() call after a deflateInit2() or deflateReset(). bits must be
663  less than or equal to 16, and that many of the least significant bits of
664  value will be inserted in the output.
665 
666  deflatePrime returns Z_OK if success, or Z_STREAM_ERROR if the source
667  stream state was inconsistent.
668 */
669 
671  gz_headerp head));
672 /*
673  deflateSetHeader() provides gzip header information for when a gzip
674  stream is requested by deflateInit2(). deflateSetHeader() may be called
675  after deflateInit2() or deflateReset() and before the first call of
676  deflate(). The text, time, os, extra field, name, and comment information
677  in the provided gz_header structure are written to the gzip header (xflag is
678  ignored -- the extra flags are set according to the compression level). The
679  caller must assure that, if not Z_NULL, name and comment are terminated with
680  a zero byte, and that if extra is not Z_NULL, that extra_len bytes are
681  available there. If hcrc is true, a gzip header crc is included. Note that
682  the current versions of the command-line version of gzip (up through version
683  1.3.x) do not support header crc's, and will report that it is a "multi-part
684  gzip file" and give up.
685 
686  If deflateSetHeader is not used, the default gzip header has text false,
687  the time set to zero, and os set to 255, with no extra, name, or comment
688  fields. The gzip header is returned to the default state by deflateReset().
689 
690  deflateSetHeader returns Z_OK if success, or Z_STREAM_ERROR if the source
691  stream state was inconsistent.
692 */
693 
694 /*
695 ZEXTERN int ZEXPORT inflateInit2 OF((z_streamp strm,
696  int windowBits));
697 
698  This is another version of inflateInit with an extra parameter. The
699  fields next_in, avail_in, zalloc, zfree and opaque must be initialized
700  before by the caller.
701 
702  The windowBits parameter is the base two logarithm of the maximum window
703  size (the size of the history buffer). It should be in the range 8..15 for
704  this version of the library. The default value is 15 if inflateInit is used
705  instead. windowBits must be greater than or equal to the windowBits value
706  provided to deflateInit2() while compressing, or it must be equal to 15 if
707  deflateInit2() was not used. If a compressed stream with a larger window
708  size is given as input, inflate() will return with the error code
709  Z_DATA_ERROR instead of trying to allocate a larger window.
710 
711  windowBits can also be -8..-15 for raw inflate. In this case, -windowBits
712  determines the window size. inflate() will then process raw deflate data,
713  not looking for a zlib or gzip header, not generating a check value, and not
714  looking for any check values for comparison at the end of the stream. This
715  is for use with other formats that use the deflate compressed data format
716  such as zip. Those formats provide their own check values. If a custom
717  format is developed using the raw deflate format for compressed data, it is
718  recommended that a check value such as an adler32 or a crc32 be applied to
719  the uncompressed data as is done in the zlib, gzip, and zip formats. For
720  most applications, the zlib format should be used as is. Note that comments
721  above on the use in deflateInit2() applies to the magnitude of windowBits.
722 
723  windowBits can also be greater than 15 for optional gzip decoding. Add
724  32 to windowBits to enable zlib and gzip decoding with automatic header
725  detection, or add 16 to decode only the gzip format (the zlib format will
726  return a Z_DATA_ERROR). If a gzip stream is being decoded, strm->adler is
727  a crc32 instead of an adler32.
728 
729  inflateInit2 returns Z_OK if success, Z_MEM_ERROR if there was not enough
730  memory, Z_STREAM_ERROR if a parameter is invalid (such as a null strm). msg
731  is set to null if there is no error message. inflateInit2 does not perform
732  any decompression apart from reading the zlib header if present: this will
733  be done by inflate(). (So next_in and avail_in may be modified, but next_out
734  and avail_out are unchanged.)
735 */
736 
738  const Bytef *dictionary,
739  uInt dictLength));
740 /*
741  Initializes the decompression dictionary from the given uncompressed byte
742  sequence. This function must be called immediately after a call of inflate,
743  if that call returned Z_NEED_DICT. The dictionary chosen by the compressor
744  can be determined from the adler32 value returned by that call of inflate.
745  The compressor and decompressor must use exactly the same dictionary (see
746  deflateSetDictionary). For raw inflate, this function can be called
747  immediately after inflateInit2() or inflateReset() and before any call of
748  inflate() to set the dictionary. The application must insure that the
749  dictionary that was used for compression is provided.
750 
751  inflateSetDictionary returns Z_OK if success, Z_STREAM_ERROR if a
752  parameter is invalid (such as NULL dictionary) or the stream state is
753  inconsistent, Z_DATA_ERROR if the given dictionary doesn't match the
754  expected one (incorrect adler32 value). inflateSetDictionary does not
755  perform any decompression: this will be done by subsequent calls of
756  inflate().
757 */
758 
760 /*
761  Skips invalid compressed data until a full flush point (see above the
762  description of deflate with Z_FULL_FLUSH) can be found, or until all
763  available input is skipped. No output is provided.
764 
765  inflateSync returns Z_OK if a full flush point has been found, Z_BUF_ERROR
766  if no more input was provided, Z_DATA_ERROR if no flush point has been found,
767  or Z_STREAM_ERROR if the stream structure was inconsistent. In the success
768  case, the application may save the current current value of total_in which
769  indicates where valid compressed data was found. In the error case, the
770  application may repeatedly call inflateSync, providing more input each time,
771  until success or end of the input data.
772 */
773 
775  z_streamp source));
776 /*
777  Sets the destination stream as a complete copy of the source stream.
778 
779  This function can be useful when randomly accessing a large stream. The
780  first pass through the stream can periodically record the inflate state,
781  allowing restarting inflate at those points when randomly accessing the
782  stream.
783 
784  inflateCopy returns Z_OK if success, Z_MEM_ERROR if there was not
785  enough memory, Z_STREAM_ERROR if the source stream state was inconsistent
786  (such as zalloc being NULL). msg is left unchanged in both source and
787  destination.
788 */
789 
791 /*
792  This function is equivalent to inflateEnd followed by inflateInit,
793  but does not free and reallocate all the internal decompression state.
794  The stream will keep attributes that may have been set by inflateInit2.
795 
796  inflateReset returns Z_OK if success, or Z_STREAM_ERROR if the source
797  stream state was inconsistent (such as zalloc or state being NULL).
798 */
799 
801  int bits,
802  int value));
803 /*
804  This function inserts bits in the inflate input stream. The intent is
805  that this function is used to start inflating at a bit position in the
806  middle of a byte. The provided bits will be used before any bytes are used
807  from next_in. This function should only be used with raw inflate, and
808  should be used before the first inflate() call after inflateInit2() or
809  inflateReset(). bits must be less than or equal to 16, and that many of the
810  least significant bits of value will be inserted in the input.
811 
812  inflatePrime returns Z_OK if success, or Z_STREAM_ERROR if the source
813  stream state was inconsistent.
814 */
815 
817  gz_headerp head));
818 /*
819  inflateGetHeader() requests that gzip header information be stored in the
820  provided gz_header structure. inflateGetHeader() may be called after
821  inflateInit2() or inflateReset(), and before the first call of inflate().
822  As inflate() processes the gzip stream, head->done is zero until the header
823  is completed, at which time head->done is set to one. If a zlib stream is
824  being decoded, then head->done is set to -1 to indicate that there will be
825  no gzip header information forthcoming. Note that Z_BLOCK can be used to
826  force inflate() to return immediately after header processing is complete
827  and before any actual data is decompressed.
828 
829  The text, time, xflags, and os fields are filled in with the gzip header
830  contents. hcrc is set to true if there is a header CRC. (The header CRC
831  was valid if done is set to one.) If extra is not Z_NULL, then extra_max
832  contains the maximum number of bytes to write to extra. Once done is true,
833  extra_len contains the actual extra field length, and extra contains the
834  extra field, or that field truncated if extra_max is less than extra_len.
835  If name is not Z_NULL, then up to name_max characters are written there,
836  terminated with a zero unless the length is greater than name_max. If
837  comment is not Z_NULL, then up to comm_max characters are written there,
838  terminated with a zero unless the length is greater than comm_max. When
839  any of extra, name, or comment are not Z_NULL and the respective field is
840  not present in the header, then that field is set to Z_NULL to signal its
841  absence. This allows the use of deflateSetHeader() with the returned
842  structure to duplicate the header. However if those fields are set to
843  allocated memory, then the application will need to save those pointers
844  elsewhere so that they can be eventually freed.
845 
846  If inflateGetHeader is not used, then the header information is simply
847  discarded. The header is always checked for validity, including the header
848  CRC if present. inflateReset() will reset the process to discard the header
849  information. The application would need to call inflateGetHeader() again to
850  retrieve the header from the next gzip stream.
851 
852  inflateGetHeader returns Z_OK if success, or Z_STREAM_ERROR if the source
853  stream state was inconsistent.
854 */
855 
856 /*
857 ZEXTERN int ZEXPORT inflateBackInit OF((z_streamp strm, int windowBits,
858  unsigned char FAR *window));
859 
860  Initialize the internal stream state for decompression using inflateBack()
861  calls. The fields zalloc, zfree and opaque in strm must be initialized
862  before the call. If zalloc and zfree are Z_NULL, then the default library-
863  derived memory allocation routines are used. windowBits is the base two
864  logarithm of the window size, in the range 8..15. window is a caller
865  supplied buffer of that size. Except for special applications where it is
866  assured that deflate was used with small window sizes, windowBits must be 15
867  and a 32K byte window must be supplied to be able to decompress general
868  deflate streams.
869 
870  See inflateBack() for the usage of these routines.
871 
872  inflateBackInit will return Z_OK on success, Z_STREAM_ERROR if any of
873  the paramaters are invalid, Z_MEM_ERROR if the internal state could not
874  be allocated, or Z_VERSION_ERROR if the version of the library does not
875  match the version of the header file.
876 */
877 
878 typedef unsigned (*in_func) OF((void FAR *, unsigned char FAR * FAR *));
879 typedef int (*out_func) OF((void FAR *, unsigned char FAR *, unsigned));
880 
882  in_func in, void FAR *in_desc,
883  out_func out, void FAR *out_desc));
884 /*
885  inflateBack() does a raw inflate with a single call using a call-back
886  interface for input and output. This is more efficient than inflate() for
887  file i/o applications in that it avoids copying between the output and the
888  sliding window by simply making the window itself the output buffer. This
889  function trusts the application to not change the output buffer passed by
890  the output function, at least until inflateBack() returns.
891 
892  inflateBackInit() must be called first to allocate the internal state
893  and to initialize the state with the user-provided window buffer.
894  inflateBack() may then be used multiple times to inflate a complete, raw
895  deflate stream with each call. inflateBackEnd() is then called to free
896  the allocated state.
897 
898  A raw deflate stream is one with no zlib or gzip header or trailer.
899  This routine would normally be used in a utility that reads zip or gzip
900  files and writes out uncompressed files. The utility would decode the
901  header and process the trailer on its own, hence this routine expects
902  only the raw deflate stream to decompress. This is different from the
903  normal behavior of inflate(), which expects either a zlib or gzip header and
904  trailer around the deflate stream.
905 
906  inflateBack() uses two subroutines supplied by the caller that are then
907  called by inflateBack() for input and output. inflateBack() calls those
908  routines until it reads a complete deflate stream and writes out all of the
909  uncompressed data, or until it encounters an error. The function's
910  parameters and return types are defined above in the in_func and out_func
911  typedefs. inflateBack() will call in(in_desc, &buf) which should return the
912  number of bytes of provided input, and a pointer to that input in buf. If
913  there is no input available, in() must return zero--buf is ignored in that
914  case--and inflateBack() will return a buffer error. inflateBack() will call
915  out(out_desc, buf, len) to write the uncompressed data buf[0..len-1]. out()
916  should return zero on success, or non-zero on failure. If out() returns
917  non-zero, inflateBack() will return with an error. Neither in() nor out()
918  are permitted to change the contents of the window provided to
919  inflateBackInit(), which is also the buffer that out() uses to write from.
920  The length written by out() will be at most the window size. Any non-zero
921  amount of input may be provided by in().
922 
923  For convenience, inflateBack() can be provided input on the first call by
924  setting strm->next_in and strm->avail_in. If that input is exhausted, then
925  in() will be called. Therefore strm->next_in must be initialized before
926  calling inflateBack(). If strm->next_in is Z_NULL, then in() will be called
927  immediately for input. If strm->next_in is not Z_NULL, then strm->avail_in
928  must also be initialized, and then if strm->avail_in is not zero, input will
929  initially be taken from strm->next_in[0 .. strm->avail_in - 1].
930 
931  The in_desc and out_desc parameters of inflateBack() is passed as the
932  first parameter of in() and out() respectively when they are called. These
933  descriptors can be optionally used to pass any information that the caller-
934  supplied in() and out() functions need to do their job.
935 
936  On return, inflateBack() will set strm->next_in and strm->avail_in to
937  pass back any unused input that was provided by the last in() call. The
938  return values of inflateBack() can be Z_STREAM_END on success, Z_BUF_ERROR
939  if in() or out() returned an error, Z_DATA_ERROR if there was a format
940  error in the deflate stream (in which case strm->msg is set to indicate the
941  nature of the error), or Z_STREAM_ERROR if the stream was not properly
942  initialized. In the case of Z_BUF_ERROR, an input or output error can be
943  distinguished using strm->next_in which will be Z_NULL only if in() returned
944  an error. If strm->next is not Z_NULL, then the Z_BUF_ERROR was due to
945  out() returning non-zero. (in() will always be called before out(), so
946  strm->next_in is assured to be defined if out() returns non-zero.) Note
947  that inflateBack() cannot return Z_OK.
948 */
949 
951 /*
952  All memory allocated by inflateBackInit() is freed.
953 
954  inflateBackEnd() returns Z_OK on success, or Z_STREAM_ERROR if the stream
955  state was inconsistent.
956 */
957 
958 //ZEXTERN uLong ZEXPORT zlibCompileFlags OF((void));
959 /* Return flags indicating compile-time options.
960 
961  Type sizes, two bits each, 00 = 16 bits, 01 = 32, 10 = 64, 11 = other:
962  1.0: size of uInt
963  3.2: size of uLong
964  5.4: size of voidpf (pointer)
965  7.6: size of z_off_t
966 
967  Compiler, assembler, and debug options:
968  8: DEBUG
969  9: ASMV or ASMINF -- use ASM code
970  10: ZLIB_WINAPI -- exported functions use the WINAPI calling convention
971  11: 0 (reserved)
972 
973  One-time table building (smaller code, but not thread-safe if true):
974  12: BUILDFIXED -- build static block decoding tables when needed
975  13: DYNAMIC_CRC_TABLE -- build CRC calculation tables when needed
976  14,15: 0 (reserved)
977 
978  Library content (indicates missing functionality):
979  16: NO_GZCOMPRESS -- gz* functions cannot compress (to avoid linking
980  deflate code when not needed)
981  17: NO_GZIP -- deflate can't write gzip streams, and inflate can't detect
982  and decode gzip streams (to avoid linking crc code)
983  18-19: 0 (reserved)
984 
985  Operation variations (changes in library functionality):
986  20: PKZIP_BUG_WORKAROUND -- slightly more permissive inflate
987  21: FASTEST -- deflate algorithm with only one, lowest compression level
988  22,23: 0 (reserved)
989 
990  The sprintf variant used by gzprintf (zero is best):
991  24: 0 = vs*, 1 = s* -- 1 means limited to 20 arguments after the format
992  25: 0 = *nprintf, 1 = *printf -- 1 means gzprintf() not secure!
993  26: 0 = returns value, 1 = void -- 1 means inferred string length returned
994 
995  Remainder:
996  27-31: 0 (reserved)
997  */
998 
999 
1000  /* utility functions */
1001 
1002 /*
1003  The following utility functions are implemented on top of the
1004  basic stream-oriented functions. To simplify the interface, some
1005  default options are assumed (compression level and memory usage,
1006  standard memory allocation functions). The source code of these
1007  utility functions can easily be modified if you need special options.
1008 */
1009 
1010 ZEXTERN int ZEXPORT compress OF((Bytef *dest, uLongf *destLen,
1011  const Bytef *source, uLong sourceLen));
1012 /*
1013  Compresses the source buffer into the destination buffer. sourceLen is
1014  the byte length of the source buffer. Upon entry, destLen is the total
1015  size of the destination buffer, which must be at least the value returned
1016  by compressBound(sourceLen). Upon exit, destLen is the actual size of the
1017  compressed buffer.
1018  This function can be used to compress a whole file at once if the
1019  input file is mmap'ed.
1020  compress returns Z_OK if success, Z_MEM_ERROR if there was not
1021  enough memory, Z_BUF_ERROR if there was not enough room in the output
1022  buffer.
1023 */
1024 
1025 ZEXTERN int ZEXPORT compress2 OF((Bytef *dest, uLongf *destLen,
1026  const Bytef *source, uLong sourceLen,
1027  int level));
1028 /*
1029  Compresses the source buffer into the destination buffer. The level
1030  parameter has the same meaning as in deflateInit. sourceLen is the byte
1031  length of the source buffer. Upon entry, destLen is the total size of the
1032  destination buffer, which must be at least the value returned by
1033  compressBound(sourceLen). Upon exit, destLen is the actual size of the
1034  compressed buffer.
1035 
1036  compress2 returns Z_OK if success, Z_MEM_ERROR if there was not enough
1037  memory, Z_BUF_ERROR if there was not enough room in the output buffer,
1038  Z_STREAM_ERROR if the level parameter is invalid.
1039 */
1040 
1041 ZEXTERN uLong ZEXPORT compressBound OF((uLong sourceLen));
1042 /*
1043  compressBound() returns an upper bound on the compressed size after
1044  compress() or compress2() on sourceLen bytes. It would be used before
1045  a compress() or compress2() call to allocate the destination buffer.
1046 */
1047 
1048 ZEXTERN int ZEXPORT uncompress OF((Bytef *dest, uLongf *destLen,
1049  const Bytef *source, uLong sourceLen));
1050 /*
1051  Decompresses the source buffer into the destination buffer. sourceLen is
1052  the byte length of the source buffer. Upon entry, destLen is the total
1053  size of the destination buffer, which must be large enough to hold the
1054  entire uncompressed data. (The size of the uncompressed data must have
1055  been saved previously by the compressor and transmitted to the decompressor
1056  by some mechanism outside the scope of this compression library.)
1057  Upon exit, destLen is the actual size of the compressed buffer.
1058  This function can be used to decompress a whole file at once if the
1059  input file is mmap'ed.
1060 
1061  uncompress returns Z_OK if success, Z_MEM_ERROR if there was not
1062  enough memory, Z_BUF_ERROR if there was not enough room in the output
1063  buffer, or Z_DATA_ERROR if the input data was corrupted or incomplete.
1064 */
1065 
1066 
1067 typedef voidp gzFile;
1068 
1069 ZEXTERN gzFile ZEXPORT gzopen OF((const char *path, const char *mode));
1070 /*
1071  Opens a gzip (.gz) file for reading or writing. The mode parameter
1072  is as in fopen ("rb" or "wb") but can also include a compression level
1073  ("wb9") or a strategy: 'f' for filtered data as in "wb6f", 'h' for
1074  Huffman only compression as in "wb1h", or 'R' for run-length encoding
1075  as in "wb1R". (See the description of deflateInit2 for more information
1076  about the strategy parameter.)
1077 
1078  gzopen can be used to read a file which is not in gzip format; in this
1079  case gzread will directly read from the file without decompression.
1080 
1081  gzopen returns NULL if the file could not be opened or if there was
1082  insufficient memory to allocate the (de)compression state; errno
1083  can be checked to distinguish the two cases (if errno is zero, the
1084  zlib error is Z_MEM_ERROR). */
1085 
1086 ZEXTERN gzFile ZEXPORT gzdopen OF((int fd, const char *mode));
1087 /*
1088  gzdopen() associates a gzFile with the file descriptor fd. File
1089  descriptors are obtained from calls like open, dup, creat, pipe or
1090  fileno (in the file has been previously opened with fopen).
1091  The mode parameter is as in gzopen.
1092  The next call of gzclose on the returned gzFile will also close the
1093  file descriptor fd, just like fclose(fdopen(fd), mode) closes the file
1094  descriptor fd. If you want to keep fd open, use gzdopen(dup(fd), mode).
1095  gzdopen returns NULL if there was insufficient memory to allocate
1096  the (de)compression state.
1097 */
1098 
1099 ZEXTERN int ZEXPORT gzsetparams OF((gzFile file, int level, int strategy));
1100 /*
1101  Dynamically update the compression level or strategy. See the description
1102  of deflateInit2 for the meaning of these parameters.
1103  gzsetparams returns Z_OK if success, or Z_STREAM_ERROR if the file was not
1104  opened for writing.
1105 */
1106 
1107 ZEXTERN int ZEXPORT gzread OF((gzFile file, voidp buf, unsigned len));
1108 /*
1109  Reads the given number of uncompressed bytes from the compressed file.
1110  If the input file was not in gzip format, gzread copies the given number
1111  of bytes into the buffer.
1112  gzread returns the number of uncompressed bytes actually read (0 for
1113  end of file, -1 for error). */
1114 
1115 ZEXTERN int ZEXPORT gzwrite OF((gzFile file,
1116  voidpc buf, unsigned len));
1117 /*
1118  Writes the given number of uncompressed bytes into the compressed file.
1119  gzwrite returns the number of uncompressed bytes actually written
1120  (0 in case of error).
1121 */
1122 
1123 ZEXTERN int ZEXPORTVA gzprintf OF((gzFile file, const char *format, ...));
1124 /*
1125  Converts, formats, and writes the args to the compressed file under
1126  control of the format string, as in fprintf. gzprintf returns the number of
1127  uncompressed bytes actually written (0 in case of error). The number of
1128  uncompressed bytes written is limited to 4095. The caller should assure that
1129  this limit is not exceeded. If it is exceeded, then gzprintf() will return
1130  return an error (0) with nothing written. In this case, there may also be a
1131  buffer overflow with unpredictable consequences, which is possible only if
1132  zlib was compiled with the insecure functions sprintf() or vsprintf()
1133  because the secure snprintf() or vsnprintf() functions were not available.
1134 */
1135 
1136 ZEXTERN int ZEXPORT gzputs OF((gzFile file, const char *s));
1137 /*
1138  Writes the given null-terminated string to the compressed file, excluding
1139  the terminating null character.
1140  gzputs returns the number of characters written, or -1 in case of error.
1141 */
1142 
1143 ZEXTERN char * ZEXPORT gzgets OF((gzFile file, char *buf, int len));
1144 /*
1145  Reads bytes from the compressed file until len-1 characters are read, or
1146  a newline character is read and transferred to buf, or an end-of-file
1147  condition is encountered. The string is then terminated with a null
1148  character.
1149  gzgets returns buf, or Z_NULL in case of error.
1150 */
1151 
1152 ZEXTERN int ZEXPORT gzputc OF((gzFile file, int c));
1153 /*
1154  Writes c, converted to an unsigned char, into the compressed file.
1155  gzputc returns the value that was written, or -1 in case of error.
1156 */
1157 
1158 ZEXTERN int ZEXPORT gzgetc OF((gzFile file));
1159 /*
1160  Reads one byte from the compressed file. gzgetc returns this byte
1161  or -1 in case of end of file or error.
1162 */
1163 
1164 ZEXTERN int ZEXPORT gzungetc OF((int c, gzFile file));
1165 /*
1166  Push one character back onto the stream to be read again later.
1167  Only one character of push-back is allowed. gzungetc() returns the
1168  character pushed, or -1 on failure. gzungetc() will fail if a
1169  character has been pushed but not read yet, or if c is -1. The pushed
1170  character will be discarded if the stream is repositioned with gzseek()
1171  or gzrewind().
1172 */
1173 
1174 ZEXTERN int ZEXPORT gzflush OF((gzFile file, int flush));
1175 /*
1176  Flushes all pending output into the compressed file. The parameter
1177  flush is as in the deflate() function. The return value is the zlib
1178  error number (see function gzerror below). gzflush returns Z_OK if
1179  the flush parameter is Z_FINISH and all output could be flushed.
1180  gzflush should be called only when strictly necessary because it can
1181  degrade compression.
1182 */
1183 
1184 ZEXTERN z_off_t ZEXPORT gzseek OF((gzFile file,
1185  z_off_t offset, int whence));
1186 /*
1187  Sets the starting position for the next gzread or gzwrite on the
1188  given compressed file. The offset represents a number of bytes in the
1189  uncompressed data stream. The whence parameter is defined as in lseek(2);
1190  the value SEEK_END is not supported.
1191  If the file is opened for reading, this function is emulated but can be
1192  extremely slow. If the file is opened for writing, only forward seeks are
1193  supported; gzseek then compresses a sequence of zeroes up to the new
1194  starting position.
1195 
1196  gzseek returns the resulting offset location as measured in bytes from
1197  the beginning of the uncompressed stream, or -1 in case of error, in
1198  particular if the file is opened for writing and the new starting position
1199  would be before the current position.
1200 */
1201 
1202 ZEXTERN int ZEXPORT gzrewind OF((gzFile file));
1203 /*
1204  Rewinds the given file. This function is supported only for reading.
1205 
1206  gzrewind(file) is equivalent to (int)gzseek(file, 0L, SEEK_SET)
1207 */
1208 
1209 ZEXTERN z_off_t ZEXPORT gztell OF((gzFile file));
1210 /*
1211  Returns the starting position for the next gzread or gzwrite on the
1212  given compressed file. This position represents a number of bytes in the
1213  uncompressed data stream.
1214 
1215  gztell(file) is equivalent to gzseek(file, 0L, SEEK_CUR)
1216 */
1217 
1218 ZEXTERN int ZEXPORT gzeof OF((gzFile file));
1219 /*
1220  Returns 1 when EOF has previously been detected reading the given
1221  input stream, otherwise zero.
1222 */
1223 
1224 ZEXTERN int ZEXPORT gzdirect OF((gzFile file));
1225 /*
1226  Returns 1 if file is being read directly without decompression, otherwise
1227  zero.
1228 */
1229 
1230 ZEXTERN int ZEXPORT gzclose OF((gzFile file));
1231 /*
1232  Flushes all pending output if necessary, closes the compressed file
1233  and deallocates all the (de)compression state. The return value is the zlib
1234  error number (see function gzerror below).
1235 */
1236 
1237 ZEXTERN const char * ZEXPORT gzerror OF((gzFile file, int *errnum));
1238 /*
1239  Returns the error message for the last error which occurred on the
1240  given compressed file. errnum is set to zlib error number. If an
1241  error occurred in the file system and not in the compression library,
1242  errnum is set to Z_ERRNO and the application may consult errno
1243  to get the exact error code.
1244 */
1245 
1246 ZEXTERN void ZEXPORT gzclearerr OF((gzFile file));
1247 /*
1248  Clears the error and end-of-file flags for file. This is analogous to the
1249  clearerr() function in stdio. This is useful for continuing to read a gzip
1250  file that is being written concurrently.
1251 */
1252 
1253  /* checksum functions */
1254 
1255 /*
1256  These functions are not related to compression but are exported
1257  anyway because they might be useful in applications using the
1258  compression library.
1259 */
1260 
1262 /*
1263  Update a running Adler-32 checksum with the bytes buf[0..len-1] and
1264  return the updated checksum. If buf is NULL, this function returns
1265  the required initial value for the checksum.
1266  An Adler-32 checksum is almost as reliable as a CRC32 but can be computed
1267  much faster. Usage example:
1268 
1269  uLong adler = adler32(0L, Z_NULL, 0);
1270 
1271  while (read_buffer(buffer, length) != EOF) {
1272  adler = adler32(adler, buffer, length);
1273  }
1274  if (adler != original_adler) error();
1275 */
1276 
1278  z_off_t len2));
1279 /*
1280  Combine two Adler-32 checksums into one. For two sequences of bytes, seq1
1281  and seq2 with lengths len1 and len2, Adler-32 checksums were calculated for
1282  each, adler1 and adler2. adler32_combine() returns the Adler-32 checksum of
1283  seq1 and seq2 concatenated, requiring only adler1, adler2, and len2.
1284 */
1285 
1287 /*
1288  Update a running CRC-32 with the bytes buf[0..len-1] and return the
1289  updated CRC-32. If buf is NULL, this function returns the required initial
1290  value for the for the crc. Pre- and post-conditioning (one's complement) is
1291  performed within this function so it shouldn't be done by the application.
1292  Usage example:
1293 
1294  uLong crc = crc32(0L, Z_NULL, 0);
1295 
1296  while (read_buffer(buffer, length) != EOF) {
1297  crc = crc32(crc, buffer, length);
1298  }
1299  if (crc != original_crc) error();
1300 */
1301 
1302 ZEXTERN uLong ZEXPORT crc32_combine OF((uLong crc1, uLong crc2, z_off_t len2));
1303 
1304 /*
1305  Combine two CRC-32 check values into one. For two sequences of bytes,
1306  seq1 and seq2 with lengths len1 and len2, CRC-32 check values were
1307  calculated for each, crc1 and crc2. crc32_combine() returns the CRC-32
1308  check value of seq1 and seq2 concatenated, requiring only crc1, crc2, and
1309  len2.
1310 */
1311 
1312 
1313  /* various hacks, don't look :) */
1314 
1315 /* deflateInit and inflateInit are macros to allow checking the zlib version
1316  * and the compiler's view of z_stream:
1317  */
1318 ZEXTERN int ZEXPORT deflateInit_ OF((z_streamp strm, int level,
1319  const char *version, int stream_size));
1321  const char *version, int stream_size));
1322 ZEXTERN int ZEXPORT deflateInit2_ OF((z_streamp strm, int level, int method,
1323  int windowBits, int memLevel,
1324  int strategy, const char *version,
1325  int stream_size));
1326 ZEXTERN int ZEXPORT inflateInit2_ OF((z_streamp strm, int windowBits,
1327  const char *version, int stream_size));
1328 ZEXTERN int ZEXPORT inflateBackInit_ OF((z_streamp strm, int windowBits,
1329  unsigned char FAR *window,
1330  const char *version,
1331  int stream_size));
1332 #define deflateInit(strm, level) \
1333  deflateInit_((strm), (level), ZLIB_VERSION, sizeof(z_stream))
1334 #define inflateInit(strm) \
1335  inflateInit_((strm), ZLIB_VERSION, sizeof(z_stream))
1336 #define deflateInit2(strm, level, method, windowBits, memLevel, strategy) \
1337  deflateInit2_((strm),(level),(method),(windowBits),(memLevel),\
1338  (strategy), ZLIB_VERSION, sizeof(z_stream))
1339 #define inflateInit2(strm, windowBits) \
1340  inflateInit2_((strm), (windowBits), ZLIB_VERSION, sizeof(z_stream))
1341 #define inflateBackInit(strm, windowBits, window) \
1342  inflateBackInit_((strm), (windowBits), (window), \
1343  ZLIB_VERSION, sizeof(z_stream))
1344 
1345 
1346 #if !defined(ZUTIL_H) && !defined(NO_DUMMY_DECL)
1347  struct internal_state {int dummy;}; /* hack for buggy compilers */
1348 #endif
1349 
1350 ZEXTERN const char * ZEXPORT zError OF((int));
1352 ZEXTERN const uLongf * ZEXPORT get_crc_table OF((void));
1353 
1354 #ifdef __cplusplus
1355 //}
1356 #endif
1357 
1358 #endif /* ZLIB_H */
int xflags
Definition: zlib.h:113
Bytef * extra
Definition: zlib.h:115
uLong ZEXPORT compressBound(uLong sourceLen)
Definition: compress.c:67
int ZEXPORT deflateParams(z_streamp strm, int level, int strategy)
Definition: deflate.c:395
Byte FAR * voidpf
Definition: zconf.h:296
int text
Definition: zlib.h:111
int ZEXPORT inflateReset(z_streamp strm)
Definition: inflate.c:103
Bytef * next_in
Definition: zlib.h:84
#define voidpf
#define ZEXPORT
int ZEXPORT uncompress(Bytef *dest, uLongf *destLen, const Bytef *source, uLong sourceLen)
Definition: uncompr.c:26
int hcrc
Definition: zlib.h:122
int ZEXPORT inflateBack(z_streamp strm, in_func in, void FAR *in_desc, out_func out, void FAR *out_desc)
Definition: infback.c:235
uLong time
Definition: zlib.h:112
uInt avail_in
Definition: zlib.h:85
int version
Definition: jpeglib.h:901
Bytef * name
Definition: zlib.h:118
int ZEXPORT inflateInit_(z_streamp strm, const char *version, int stream_size)
Definition: inflate.c:179
uInt extra_max
Definition: zlib.h:117
char * msg
Definition: zlib.h:92
uInt name_max
Definition: zlib.h:119
int done
Definition: zlib.h:123
Definition: zlib.h:110
unsigned long uLong
Definition: zconf.h:277
int ZEXPORT deflateInit2_(z_streamp strm, int level, int method, int windowBits, int memLevel, int strategy, const char *version, int stream_size)
Definition: deflate.c:212
uLong ZEXPORT deflateBound(z_streamp strm, uLong sourceLen)
Definition: deflate.c:460
int ZEXPORT deflateEnd(z_streamp strm)
Definition: deflate.c:823
struct gz_header_s gz_header
int ZEXPORT deflatePrime(z_streamp strm, int bits, int value)
Definition: deflate.c:386
gz_header FAR * gz_headerp
Definition: zlib.h:127
#define FAR
int ZEXPORT inflateBackInit_(z_streamp strm, int windowBits, unsigned char FAR *window, const char *version, int stream_size)
Definition: infback.c:28
#define in_func
Byte FAR Bytef
Definition: zconf.h:283
voidpf opaque
Definition: zlib.h:97
struct internal_state FAR * state
Definition: zlib.h:93
voidp gzFile
Definition: zlib.h:1067
free_func zfree
Definition: zlib.h:96
int ZEXPORT inflateSetDictionary(z_streamp strm, const Bytef *dictionary, uInt dictLength)
Definition: inflate.c:1152
int ZEXPORT inflateSyncPoint(z_streamp strm)
Definition: inflate.c:1287
uLong reserved
Definition: zlib.h:101
#define const
png_uint_32 adler
Definition: juce_PNGLoader.cpp:2078
uInt extra_len
Definition: zlib.h:116
const unsigned long FAR *ZEXPORT get_crc_table()
Definition: crc32.c:205
png_structrp int mode
Definition: juce_PNGLoader.cpp:1243
#define free_func
int data_type
Definition: zlib.h:99
unsigned long ZEXPORT crc32(unsigned long crc, const unsigned char FAR *buf, unsigned len)
Definition: crc32.c:219
uLong ZEXPORT crc32_combine(uLong crc1, uLong crc2, z_off_t len2)
Definition: crc32.c:357
#define ZEXTERN
png_uint_32 crc
Definition: juce_PNGLoader.cpp:2078
int ZEXPORT deflateCopy(z_streamp dest, z_streamp source)
Definition: deflate.c:857
int ZEXPORT deflateTune(z_streamp strm, int good_length, int max_lazy, int nice_length, int max_chain)
Definition: deflate.c:430
#define ZEXPORTVA
int os
Definition: zlib.h:114
uLong total_in
Definition: zlib.h:86
int ZEXPORT compress2(Bytef *dest, uLongf *destLen, const Bytef *source, uLong sourceLen, int level)
Definition: compress.c:22
alloc_func zalloc
Definition: zlib.h:95
Bytef * next_out
Definition: zlib.h:88
int ZEXPORT inflateBackEnd(z_streamp strm)
Definition: infback.c:603
int ZEXPORT inflateSync(z_streamp strm)
Definition: inflate.c:1237
Byte * voidp
Definition: zconf.h:297
int ZEXPORT deflate(z_streamp strm, int flush)
Definition: deflate.c:518
int ZEXPORT inflateGetHeader(z_streamp strm, gz_headerp head)
Definition: inflate.c:1191
#define alloc_func
Bytef * comment
Definition: zlib.h:120
int dummy
Definition: zlib.h:1347
uLong adler
Definition: zlib.h:100
uLong total_out
Definition: zlib.h:90
uLong ZEXPORT adler32(uLong adler, const Bytef *buf, uInt len)
Definition: adler32.c:57
int ZEXPORT inflateInit2_(z_streamp strm, int windowBits, const char *version, int stream_size)
Definition: inflate.c:140
uLong FAR uLongf
Definition: zconf.h:288
int ZEXPORT compress(Bytef *dest, uLongf *destLen, const Bytef *source, uLong sourceLen)
Definition: compress.c:58
Definition: deflate.h:96
int ZEXPORT inflatePrime(z_streamp strm, int bits, int value)
Definition: inflate.c:127
uInt comm_max
Definition: zlib.h:121
int ZEXPORT deflateSetDictionary(z_streamp strm, const Bytef *dictionary, uInt dictLength)
Definition: deflate.c:302
int ZEXPORT deflateSetHeader(z_streamp strm, gz_headerp head)
Definition: deflate.c:377
uInt avail_out
Definition: zlib.h:89
int ZEXPORT deflateInit_(z_streamp strm, int level, const char *version, int stream_size)
Definition: deflate.c:204
int ZEXPORT inflate(z_streamp strm, int flush)
Definition: inflate.c:540
const char *ZEXPORT zError(int err)
Definition: zutil.c:132
#define z_off_t
int ZEXPORT inflateCopy(z_streamp dest, z_streamp source)
Definition: inflate.c:1296
struct z_stream_s z_stream
z_stream FAR * z_streamp
Definition: zlib.h:104
int ZEXPORT deflateReset(z_streamp strm)
Definition: deflate.c:342
Byte const * voidpc
Definition: zconf.h:295
uLong ZEXPORT adler32_combine(uLong adler1, uLong adler2, z_off_t len2)
Definition: adler32.c:125
voidpf alloc_func OF((voidpf opaque, uInt items, uInt size))
Definition: zlib.h:78
#define out_func
int ZEXPORT inflateEnd(z_streamp strm)
Definition: inflate.c:1139
Definition: zlib.h:83
unsigned int uInt
Definition: zconf.h:276