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First entry of Paradise Server 2.9 patch 10 Beta
author darius
date Sat, 06 Dec 1997 04:37:18 +0000
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1 /* zlib.h -- interface of the 'zlib' general purpose compression library
2 version 0.92 May 3rd, 1995.
3
4 Copyright (C) 1995 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 gzip@prep.ai.mit.edu madler@cco.caltech.edu
24 */
25
26 #ifndef _ZLIB_H
27 #define _ZLIB_H
28
29 #include "zconf.h"
30
31 #define ZLIB_VERSION "0.92"
32
33 /*
34 The 'zlib' compression library provides in-memory compression and
35 decompression functions, including integrity checks of the uncompressed
36 data. This version of the library supports only one compression method
37 (deflation) but other algorithms may be added later and will have the same
38 stream interface.
39
40 For compression the application must provide the output buffer and
41 may optionally provide the input buffer for optimization. For decompression,
42 the application must provide the input buffer and may optionally provide
43 the output buffer for optimization.
44
45 Compression can be done in a single step if the buffers are large
46 enough (for example if an input file is mmap'ed), or can be done by
47 repeated calls of the compression function. In the latter case, the
48 application must provide more input and/or consume the output
49 (providing more output space) before each call.
50 */
51
52 typedef voidp (*alloc_func) __P((voidp opaque, uInt items, uInt size));
53 typedef void (*free_func) __P((voidp opaque, voidp address));
54
55 struct internal_state;
56
57 typedef struct z_stream_s {
58 Byte *next_in; /* next input byte */
59 uInt avail_in; /* number of bytes available at next_in */
60 uLong total_in; /* total nb of input bytes read so far */
61
62 Byte *next_out; /* next output byte should be put there */
63 uInt avail_out; /* remaining free space at next_out */
64 uLong total_out; /* total nb of bytes output so far */
65
66 char *msg; /* last error message, NULL if no error */
67 struct internal_state *state; /* not visible by applications */
68
69 alloc_func zalloc; /* used to allocate the internal state */
70 free_func zfree; /* used to free the internal state */
71 voidp opaque; /* private data object passed to zalloc and zfree */
72
73 Byte data_type; /* best guess about the data type: ascii or binary */
74
75 } z_stream;
76
77 /*
78 The application must update next_in and avail_in when avail_in has
79 dropped to zero. It must update next_out and avail_out when avail_out
80 has dropped to zero. The application must initialize zalloc, zfree and
81 opaque before calling the init function. All other fields are set by the
82 compression library and must not be updated by the application.
83
84 The opaque value provided by the application will be passed as the first
85 parameter for calls of zalloc and zfree. This can be useful for custom
86 memory management. The compression library attaches no meaning to the
87 opaque value.
88
89 zalloc must return Z_NULL if there is not enough memory for the object.
90 On 16-bit systems, the functions zalloc and zfree must be able to allocate
91 exactly 65536 bytes, but will not be required to allocate more than this
92 if the symbol MAXSEG_64K is defined (see zconf.h). WARNING: On MSDOS,
93 pointers returned by zalloc for objects of exactly 65536 bytes *must*
94 have their offset normalized to zero. The default allocation function
95 provided by this library ensures this (see zutil.c). To reduce memory
96 requirements and avoid any allocation of 64K objects, at the expense of
97 compression ratio, compile the library with -DMAX_WBITS=14 (see zconf.h).
98
99 The fields total_in and total_out can be used for statistics or
100 progress reports. After compression, total_in holds the total size of
101 the uncompressed data and may be saved for use in the decompressor
102 (particularly if the decompressor wants to decompress everything in
103 a single step).
104 */
105
106 /* constants */
107
108 #define Z_NO_FLUSH 0
109 #define Z_PARTIAL_FLUSH 1
110 #define Z_FULL_FLUSH 2
111 #define Z_FINISH 4
112 /* See deflate() below for the usage of these constants */
113
114 #define Z_OK 0
115 #define Z_STREAM_END 1
116 #define Z_ERRNO (-1)
117 #define Z_STREAM_ERROR (-2)
118 #define Z_DATA_ERROR (-3)
119 #define Z_MEM_ERROR (-4)
120 #define Z_BUF_ERROR (-5)
121 /* error codes for the compression/decompression functions */
122
123 #define Z_BEST_SPEED 1
124 #define Z_BEST_COMPRESSION 9
125 #define Z_DEFAULT_COMPRESSION (-1)
126 /* compression levels */
127
128 #define Z_FILTERED 1
129 #define Z_HUFFMAN_ONLY 2
130 #define Z_DEFAULT_STRATEGY 0
131
132 #define Z_BINARY 0
133 #define Z_ASCII 1
134 #define Z_UNKNOWN 2
135 /* Used to set the data_type field */
136
137 #define Z_NULL 0 /* for initializing zalloc, zfree, opaque */
138
139 extern char *zlib_version;
140 /* The application can compare zlib_version and ZLIB_VERSION for consistency.
141 If the first character differs, the library code actually used is
142 not compatible with the zlib.h header file used by the application.
143 */
144
145 /* basic functions */
146
147 extern int deflateInit __P((z_stream *strm, int level));
148 /*
149 Initializes the internal stream state for compression. The fields
150 zalloc, zfree and opaque must be initialized before by the caller.
151 If zalloc and zfree are set to Z_NULL, deflateInit updates them to
152 use default allocation functions.
153
154 The compression level must be Z_DEFAULT_COMPRESSION, or between 1 and 9:
155 1 gives best speed, 9 gives best compression. Z_DEFAULT_COMPRESSION requests
156 a default compromise between speed and compression (currently equivalent
157 to level 6).
158
159 deflateInit returns Z_OK if success, Z_MEM_ERROR if there was not
160 enough memory, Z_STREAM_ERROR if level is not a valid compression level.
161 msg is set to null if there is no error message. deflateInit does not
162 perform any compression: this will be done by deflate().
163 */
164
165
166 extern int deflate __P((z_stream *strm, int flush));
167 /*
168 Performs one or both of the following actions:
169
170 - Compress more input starting at next_in and update next_in and avail_in
171 accordingly. If not all input can be processed (because there is not
172 enough room in the output buffer), next_in and avail_in are updated and
173 processing will resume at this point for the next call of deflate().
174
175 - Provide more output starting at next_out and update next_out and avail_out
176 accordingly. This action is forced if the parameter flush is non zero.
177 Forcing flush frequently degrades the compression ratio, so this parameter
178 should be set only when necessary (in interactive applications).
179 Some output may be provided even if flush is not set.
180
181 Before the call of deflate(), the application should ensure that at least
182 one of the actions is possible, by providing more input and/or consuming
183 more output, and updating avail_in or avail_out accordingly; avail_out
184 should never be zero before the call. The application can consume the
185 compressed output when it wants, for example when the output buffer is full
186 (avail_out == 0), or after each call of deflate().
187
188 If the parameter flush is set to Z_PARTIAL_FLUSH, the current compression
189 block is terminated and flushed to the output buffer so that the
190 decompressor can get all input data available so far. For method 9, a future
191 variant on method 8, the current block will be flushed but not terminated.
192 If flush is set to Z_FULL_FLUSH, the compression block is terminated, a
193 special marker is output and the compression dictionary is discarded; this
194 is useful to allow the decompressor to synchronize if one compressed block
195 has been damaged (see inflateSync below). Flushing degrades compression and
196 so should be used only when necessary. Using Z_FULL_FLUSH too often can
197 seriously degrade the compression.
198
199 If the parameter flush is set to Z_FINISH, all pending input is processed,
200 all pending output is flushed and deflate returns with Z_STREAM_END if there
201 was enough output space; if deflate returns with Z_OK, this function must be
202 called again with Z_FINISH and more output space (updated avail_out) but no
203 more input data, until it returns with Z_STREAM_END or an error. After
204 deflate has returned Z_STREAM_END, the only possible operations on the
205 stream are deflateReset or deflateEnd.
206
207 Z_FINISH can be used immediately after deflateInit if all the compression
208 is to be done in a single step. In this case, avail_out must be at least
209 0.1% larger than avail_in plus 12 bytes. If deflate does not return
210 Z_STREAM_END, then it must be called again as described above.
211
212 deflate() may update data_type if it can make a good guess about
213 the input data type (Z_ASCII or Z_BINARY). In doubt, the data is considered
214 binary. This field is only for information purposes and does not affect
215 the compression algorithm in any manner.
216
217 deflate() returns Z_OK if some progress has been made (more input
218 processed or more output produced), Z_STREAM_END if all input has been
219 consumed and all output has been produced (only when flush is set to
220 Z_FINISH), Z_STREAM_ERROR if the stream state was inconsistent (for example
221 if next_in or next_out was NULL), Z_BUF_ERROR if no progress is possible.
222 */
223
224
225 extern int deflateEnd __P((z_stream *strm));
226 /*
227 All dynamically allocated data structures for this stream are freed.
228 This function discards any unprocessed input and does not flush any
229 pending output.
230
231 deflateEnd returns Z_OK if success, Z_STREAM_ERROR if the
232 stream state was inconsistent. In the error case, msg may be set
233 but then points to a static string (which must not be deallocated).
234 */
235
236
237 extern int inflateInit __P((z_stream *strm));
238 /*
239 Initializes the internal stream state for decompression. The fields
240 zalloc and zfree must be initialized before by the caller. If zalloc and
241 zfree are set to Z_NULL, deflateInit updates them to use default allocation
242 functions.
243
244 inflateInit returns Z_OK if success, Z_MEM_ERROR if there was not
245 enough memory. msg is set to null if there is no error message.
246 inflateInit does not perform any decompression: this will be done by
247 inflate().
248 */
249
250
251 extern int inflate __P((z_stream *strm, int flush));
252 /*
253 Performs one or both of the following actions:
254
255 - Decompress more input starting at next_in and update next_in and avail_in
256 accordingly. If not all input can be processed (because there is not
257 enough room in the output buffer), next_in is updated and processing
258 will resume at this point for the next call of inflate().
259
260 - Provide more output starting at next_out and update next_out and avail_out
261 accordingly. inflate() always provides as much output as possible
262 (until no more input data or no more space in the output buffer).
263
264 Before the call of inflate(), 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 the next_* and avail_* values accordingly.
267 The application can consume the uncompressed output when it wants, for
268 example when the output buffer is full (avail_out == 0), or after each
269 call of inflate().
270
271 If the parameter flush is set to Z_PARTIAL_FLUSH, inflate flushes as much
272 output as possible to the output buffer. The flushing behavior of inflate is
273 not specified for values of the flush parameter other than Z_PARTIAL_FLUSH
274 and Z_FINISH, but the current implementation actually flushes as much output
275 as possible anyway.
276
277 inflate() should normally be called until it returns Z_STREAM_END or an
278 error. However if all decompression is to be performed in a single step
279 (a single call of inflate), the parameter flush should be set to
280 Z_FINISH. In this case all pending input is processed and all pending
281 output is flushed; avail_out must be large enough to hold all the
282 uncompressed data. (The size of the uncompressed data may have been saved
283 by the compressor for this purpose.) The next operation on this stream must
284 be inflateEnd to deallocate the decompression state.
285
286 inflate() returns Z_OK if some progress has been made (more input
287 processed or more output produced), Z_STREAM_END if the end of the
288 compressed data has been reached and all uncompressed output has been
289 produced, Z_DATA_ERROR if the input data was corrupted, Z_STREAM_ERROR if
290 the stream structure was inconsistent (for example if next_in or next_out
291 was NULL), Z_MEM_ERROR if there was not enough memory, Z_BUF_ERROR if no
292 progress is possible or if there was not enough room in the output buffer
293 when Z_FINISH is used. In the Z_DATA_ERROR case, the application may then
294 call inflateSync to look for a good compression block.
295 */
296
297
298 extern int inflateEnd __P((z_stream *strm));
299 /*
300 All dynamically allocated data structures for this stream are freed.
301 This function discards any unprocessed input and does not flush any
302 pending output.
303
304 inflateEnd returns Z_OK if success, Z_STREAM_ERROR if the stream state
305 was inconsistent. In the error case, msg may be set but then points to a
306 static string (which must not be deallocated).
307 */
308
309 /* advanced functions */
310
311 /*
312 The following functions are needed only in some special applications.
313 */
314
315 extern int deflateInit2 __P((z_stream *strm,
316 int level,
317 int method,
318 int windowBits,
319 int memLevel,
320 int strategy));
321 /*
322 This is another version of deflateInit with more compression options. The
323 fields next_in, zalloc and zfree must be initialized before by the caller.
324
325 The method parameter is the compression method. It must be 8 in this
326 version of the library. (Method 9 will allow a 64K history buffer and
327 partial block flushes.)
328
329 The windowBits parameter is the base two logarithm of the window size
330 (the size of the history buffer). It should be in the range 8..15 for this
331 version of the library (the value 16 will be allowed for method 9). Larger
332 values of this parameter result in better compression at the expense of
333 memory usage. The default value is 15 if deflateInit is used instead.
334
335 The memLevel parameter specifies how much memory should be allocated
336 for the internal compression state. memLevel=1 uses minimum memory but
337 is slow and reduces compression ratio; memLevel=9 uses maximum memory
338 for optimal speed. The default value is 8. See zconf.h for total memory
339 usage as a function of windowBits and memLevel.
340
341 The strategy parameter is used to tune the compression algorithm. Use
342 the value Z_DEFAULT_STRATEGY for normal data, Z_FILTERED for data
343 produced by a filter (or predictor), or Z_HUFFMAN_ONLY to force Huffman
344 encoding only (no string match). Filtered data consists mostly of small
345 values with a somewhat random distribution. In this case, the
346 compression algorithm is tuned to compress them better. The strategy
347 parameter only affects the compression ratio but not the correctness of
348 the compressed output even if it is not set appropriately.
349
350 If next_in is not null, the library will use this buffer to hold also
351 some history information; the buffer must either hold the entire input
352 data, or have at least 1<<(windowBits+1) bytes and be writable. If next_in
353 is null, the library will allocate its own history buffer (and leave next_in
354 null). next_out need not be provided here but must be provided by the
355 application for the next call of deflate().
356
357 If the history buffer is provided by the application, next_in must
358 must never be changed by the application since the compressor maintains
359 information inside this buffer from call to call; the application
360 must provide more input only by increasing avail_in. next_in is always
361 reset by the library in this case.
362
363 deflateInit2 returns Z_OK if success, Z_MEM_ERROR if there was
364 not enough memory, Z_STREAM_ERROR if a parameter is invalid (such as
365 an invalid method). msg is set to null if there is no error message.
366 deflateInit2 does not perform any compression: this will be done by
367 deflate().
368 */
369
370 extern int deflateCopy __P((z_stream *dest,
371 z_stream *source));
372 /*
373 Sets the destination stream as a complete copy of the source stream. If
374 the source stream is using an application-supplied history buffer, a new
375 buffer is allocated for the destination stream. The compressed output
376 buffer is always application-supplied. It's the responsibility of the
377 application to provide the correct values of next_out and avail_out for the
378 next call of deflate.
379
380 This function is useful when several compression strategies will be
381 tried, for example when there are several ways of pre-processing the input
382 data with a filter. The streams that will be discarded should then be freed
383 by calling deflateEnd. Note that deflateCopy duplicates the internal
384 compression state which can be quite large, so this strategy is slow and
385 can consume lots of memory.
386
387 deflateCopy returns Z_OK if success, Z_MEM_ERROR if there was not
388 enough memory, Z_STREAM_ERROR if the source stream state was inconsistent
389 (such as zalloc being NULL). msg is left unchanged in both source and
390 destination.
391 */
392
393 extern int deflateReset __P((z_stream *strm));
394 /*
395 This function is equivalent to deflateEnd followed by deflateInit,
396 but does not free and reallocate all the internal compression state.
397 The stream will keep the same compression level and any other attributes
398 that may have been set by deflateInit2.
399
400 deflateReset returns Z_OK if success, or Z_STREAM_ERROR if the source
401 stream state was inconsistent (such as zalloc or state being NULL).
402 */
403
404 extern int inflateInit2 __P((z_stream *strm,
405 int windowBits));
406 /*
407 This is another version of inflateInit with more compression options. The
408 fields next_out, zalloc and zfree must be initialized before by the caller.
409
410 The windowBits parameter is the base two logarithm of the maximum window
411 size (the size of the history buffer). It should be in the range 8..15 for
412 this version of the library (the value 16 will be allowed soon). The
413 default value is 15 if inflateInit is used instead. If a compressed stream
414 with a larger window size is given as input, inflate() will return with
415 the error code Z_DATA_ERROR instead of trying to allocate a larger window.
416
417 If next_out is not null, the library will use this buffer for the history
418 buffer; the buffer must either be large enough to hold the entire output
419 data, or have at least 1<<windowBits bytes. If next_out is null, the
420 library will allocate its own buffer (and leave next_out null). next_in
421 need not be provided here but must be provided by the application for the
422 next call of inflate().
423
424 If the history buffer is provided by the application, next_out must
425 never be changed by the application since the decompressor maintains
426 history information inside this buffer from call to call; the application
427 can only reset next_out to the beginning of the history buffer when
428 avail_out is zero and all output has been consumed.
429
430 inflateInit2 returns Z_OK if success, Z_MEM_ERROR if there was
431 not enough memory, Z_STREAM_ERROR if a parameter is invalid (such as
432 windowBits < 8). msg is set to null if there is no error message.
433 inflateInit2 does not perform any compression: this will be done by
434 inflate().
435 */
436
437 extern int inflateSync __P((z_stream *strm));
438 /*
439 Skips invalid compressed data until the special marker (see deflate()
440 above) can be found, or until all available input is skipped. No output
441 is provided.
442
443 inflateSync returns Z_OK if the special marker has been found, Z_BUF_ERROR
444 if no more input was provided, Z_DATA_ERROR if no marker has been found,
445 or Z_STREAM_ERROR if the stream structure was inconsistent. In the success
446 case, the application may save the current current value of total_in which
447 indicates where valid compressed data was found. In the error case, the
448 application may repeatedly call inflateSync, providing more input each time,
449 until success or end of the input data.
450 */
451
452 extern int inflateReset __P((z_stream *strm));
453 /*
454 This function is equivalent to inflateEnd followed by inflateInit,
455 but does not free and reallocate all the internal decompression state.
456 The stream will keep attributes that may have been set by inflateInit2.
457
458 inflateReset returns Z_OK if success, or Z_STREAM_ERROR if the source
459 stream state was inconsistent (such as zalloc or state being NULL).
460 */
461
462
463 /* utility functions */
464
465 /*
466 The following utility functions are implemented on top of the
467 basic stream-oriented functions. To simplify the interface, some
468 default options are assumed (compression level, window size,
469 standard memory allocation functions). The source code of these
470 utility functions can easily be modified if you need special options.
471 */
472
473 extern int compress __P((Byte *dest, uLong *destLen,
474 Byte *source, uLong sourceLen));
475 /*
476 Compresses the source buffer into the destination buffer. sourceLen is
477 the byte length of the source buffer. Upon entry, destLen is the total
478 size of the destination buffer, which must be at least 0.1% larger than
479 sourceLen plus 12 bytes. Upon exit, destLen is the actual size of the
480 compressed buffer.
481 This function can be used to compress a whole file at once if the
482 input file is mmap'ed.
483 compress returns Z_OK if success, Z_MEM_ERROR if there was not
484 enough memory, Z_BUF_ERROR if there was not enough room in the output
485 buffer.
486 */
487
488 extern int uncompress __P((Byte *dest, uLong *destLen,
489 Byte *source, uLong sourceLen));
490 /*
491 Decompresses the source buffer into the destination buffer. sourceLen is
492 the byte length of the source buffer. Upon entry, destLen is the total
493 size of the destination buffer, which must be large enough to hold the
494 entire uncompressed data. (The size of the uncompressed data must have
495 been saved previously by the compressor and transmitted to the decompressor
496 by some mechanism outside the scope of this compression library.)
497 Upon exit, destLen is the actual size of the compressed buffer.
498 This function can be used to decompress a whole file at once if the
499 input file is mmap'ed.
500
501 uncompress returns Z_OK if success, Z_MEM_ERROR if there was not
502 enough memory, Z_BUF_ERROR if there was not enough room in the output
503 buffer, or Z_DATA_ERROR if the input data was corrupted.
504 */
505
506
507 typedef voidp gzFile;
508
509 extern gzFile gzopen __P((char *path, char *mode));
510 /*
511 Opens a gzip (.gz) file for reading or writing. The mode parameter
512 is as in fopen ("rb" or "wb"). gzopen can also be used to read a file
513 which is not in gzip format; in this case gzread will directly read from
514 the file without decompression.
515 gzopen returns NULL if the file could not be opened or if there was
516 insufficient memory to allocate the (de)compression state; errno
517 can be checked to distinguish the two cases (if errno is zero, the
518 zlib error is Z_MEM_ERROR).
519 */
520
521 extern gzFile gzdopen __P((int fd, char *mode));
522 /*
523 gzdopen() associates a gzFile with the file descriptor fd. File
524 descriptors are obtained from calls like open, dup, creat, or pipe.
525 The mode parameter is as in fopen ("rb" or "wb").
526 gzdopen returns NULL if there was insufficient memory to allocate
527 the (de)compression state.
528 */
529
530 extern int gzread __P((gzFile file, voidp buf, unsigned len));
531 /*
532 Reads the given number of uncompressed bytes from the compressed file.
533 If the input file was not in gzip format, gzread copies the given number
534 of bytes into the buffer.
535 gzread returns the number of uncompressed bytes actually read (0 for
536 end of file, -1 for error). */
537
538 extern int gzwrite __P((gzFile file, voidp buf, unsigned len));
539 /*
540 Writes the given number of uncompressed bytes into the compressed file.
541 gzwrite returns the number of uncompressed bytes actually written
542 (0 in case of error).
543 */
544
545 extern int gzflush __P((gzFile file, int flush));
546 /*
547 Flushes all pending output into the compressed file. The parameter
548 flush is as in the deflate() function. The return value is the zlib
549 error number (see function gzerror below). gzflush returns Z_OK if
550 the flush parameter is Z_FINISH and all output could be flushed.
551 gzflush should be called only when strictly necessary because it can
552 degrade compression.
553 */
554
555 extern int gzclose __P((gzFile file));
556 /*
557 Flushes all pending output if necessary, closes the compressed file
558 and deallocates all the (de)compression state. The return value is the zlib
559 error number (see function gzerror below).
560 */
561
562 extern char* gzerror __P((gzFile file, int *errnum));
563 /*
564 Returns the error message for the last error which occurred on the
565 given compressed file. errnum is set to zlib error number. If an
566 error occurred in the file system and not in the compression library,
567 errnum is set to Z_ERRNO and the application may consult errno
568 to get the exact error code.
569 */
570
571 /* checksum functions */
572
573 /*
574 These functions are not related to compression but are exported
575 anyway because they might be useful in applications using the
576 compression library.
577 */
578
579 extern uLong adler32 __P((uLong adler, Byte *buf, uInt len));
580 /*
581 Update a running Adler-32 checksum with the bytes buf[0..len-1] and
582 return the updated checksum. If buf is NULL, this function returns
583 the required initial value for the checksum.
584 An Adler-32 checksum is almost as reliable as a CRC32 but can be computed
585 much faster. Usage example:
586
587 uLong adler = adler32(0L, Z_NULL, 0);
588
589 while (read_buffer(buffer, length) != EOF) {
590 adler = adler32(adler, buffer, length);
591 }
592 if (adler != original_adler) error();
593 */
594
595 extern uLong crc32 __P((uLong crc, Byte *buf, uInt len));
596 /*
597 Update a running crc with the bytes buf[0..len-1] and return the updated
598 crc. If buf is NULL, this function returns the required initial value
599 for the crc. Pre- and post-conditioning (one's complement) is performed
600 within this function so it shouldn't be done by the application.
601 Usage example:
602
603 uLong crc = crc32(0L, Z_NULL, 0);
604
605 while (read_buffer(buffer, length) != EOF) {
606 crc = crc32(crc, buffer, length);
607 }
608 if (crc != original_crc) error();
609 */
610
611 #ifndef _Z_UTIL_H
612 struct internal_state {int dummy;}; /* hack for buggy compilers */
613 #endif
614
615 #endif /* _ZLIB_H */