1.1 --- a/core/zlib/zlib.h Fri Mar 28 06:21:34 2008 +0000
1.2 +++ /dev/null Thu Jan 01 00:00:00 1970 +0000
1.3 @@ -1,1357 +0,0 @@
1.4 -/* zlib.h -- interface of the 'zlib' general purpose compression library
1.5 - version 1.2.3, July 18th, 2005
1.6 -
1.7 - Copyright (C) 1995-2005 Jean-loup Gailly and Mark Adler
1.8 -
1.9 - This software is provided 'as-is', without any express or implied
1.10 - warranty. In no event will the authors be held liable for any damages
1.11 - arising from the use of this software.
1.12 -
1.13 - Permission is granted to anyone to use this software for any purpose,
1.14 - including commercial applications, and to alter it and redistribute it
1.15 - freely, subject to the following restrictions:
1.16 -
1.17 - 1. The origin of this software must not be misrepresented; you must not
1.18 - claim that you wrote the original software. If you use this software
1.19 - in a product, an acknowledgment in the product documentation would be
1.20 - appreciated but is not required.
1.21 - 2. Altered source versions must be plainly marked as such, and must not be
1.22 - misrepresented as being the original software.
1.23 - 3. This notice may not be removed or altered from any source distribution.
1.24 -
1.25 - Jean-loup Gailly Mark Adler
1.26 - [email protected] [email protected]
1.27 -
1.28 -
1.29 - The data format used by the zlib library is described by RFCs (Request for
1.30 - Comments) 1950 to 1952 in the files http://www.ietf.org/rfc/rfc1950.txt
1.31 - (zlib format), rfc1951.txt (deflate format) and rfc1952.txt (gzip format).
1.32 -*/
1.33 -
1.34 -#ifndef ZLIB_H
1.35 -#define ZLIB_H
1.36 -
1.37 -#include "zconf.h"
1.38 -
1.39 -#ifdef __cplusplus
1.40 -extern "C" {
1.41 -#endif
1.42 -
1.43 -#define ZLIB_VERSION "1.2.3"
1.44 -#define ZLIB_VERNUM 0x1230
1.45 -
1.46 -/*
1.47 - The 'zlib' compression library provides in-memory compression and
1.48 - decompression functions, including integrity checks of the uncompressed
1.49 - data. This version of the library supports only one compression method
1.50 - (deflation) but other algorithms will be added later and will have the same
1.51 - stream interface.
1.52 -
1.53 - Compression can be done in a single step if the buffers are large
1.54 - enough (for example if an input file is mmap'ed), or can be done by
1.55 - repeated calls of the compression function. In the latter case, the
1.56 - application must provide more input and/or consume the output
1.57 - (providing more output space) before each call.
1.58 -
1.59 - The compressed data format used by default by the in-memory functions is
1.60 - the zlib format, which is a zlib wrapper documented in RFC 1950, wrapped
1.61 - around a deflate stream, which is itself documented in RFC 1951.
1.62 -
1.63 - The library also supports reading and writing files in gzip (.gz) format
1.64 - with an interface similar to that of stdio using the functions that start
1.65 - with "gz". The gzip format is different from the zlib format. gzip is a
1.66 - gzip wrapper, documented in RFC 1952, wrapped around a deflate stream.
1.67 -
1.68 - This library can optionally read and write gzip streams in memory as well.
1.69 -
1.70 - The zlib format was designed to be compact and fast for use in memory
1.71 - and on communications channels. The gzip format was designed for single-
1.72 - file compression on file systems, has a larger header than zlib to maintain
1.73 - directory information, and uses a different, slower check method than zlib.
1.74 -
1.75 - The library does not install any signal handler. The decoder checks
1.76 - the consistency of the compressed data, so the library should never
1.77 - crash even in case of corrupted input.
1.78 -*/
1.79 -
1.80 -typedef voidpf (*alloc_func) OF((voidpf opaque, uInt items, uInt size));
1.81 -typedef void (*free_func) OF((voidpf opaque, voidpf address));
1.82 -
1.83 -struct internal_state;
1.84 -
1.85 -typedef struct z_stream_s {
1.86 - Bytef *next_in; /* next input byte */
1.87 - uInt avail_in; /* number of bytes available at next_in */
1.88 - uLong total_in; /* total nb of input bytes read so far */
1.89 -
1.90 - Bytef *next_out; /* next output byte should be put there */
1.91 - uInt avail_out; /* remaining free space at next_out */
1.92 - uLong total_out; /* total nb of bytes output so far */
1.93 -
1.94 - char *msg; /* last error message, NULL if no error */
1.95 - struct internal_state FAR *state; /* not visible by applications */
1.96 -
1.97 - alloc_func zalloc; /* used to allocate the internal state */
1.98 - free_func zfree; /* used to free the internal state */
1.99 - voidpf opaque; /* private data object passed to zalloc and zfree */
1.100 -
1.101 - int data_type; /* best guess about the data type: binary or text */
1.102 - uLong adler; /* adler32 value of the uncompressed data */
1.103 - uLong reserved; /* reserved for future use */
1.104 -} z_stream;
1.105 -
1.106 -typedef z_stream FAR *z_streamp;
1.107 -
1.108 -/*
1.109 - gzip header information passed to and from zlib routines. See RFC 1952
1.110 - for more details on the meanings of these fields.
1.111 -*/
1.112 -typedef struct gz_header_s {
1.113 - int text; /* true if compressed data believed to be text */
1.114 - uLong time; /* modification time */
1.115 - int xflags; /* extra flags (not used when writing a gzip file) */
1.116 - int os; /* operating system */
1.117 - Bytef *extra; /* pointer to extra field or Z_NULL if none */
1.118 - uInt extra_len; /* extra field length (valid if extra != Z_NULL) */
1.119 - uInt extra_max; /* space at extra (only when reading header) */
1.120 - Bytef *name; /* pointer to zero-terminated file name or Z_NULL */
1.121 - uInt name_max; /* space at name (only when reading header) */
1.122 - Bytef *comment; /* pointer to zero-terminated comment or Z_NULL */
1.123 - uInt comm_max; /* space at comment (only when reading header) */
1.124 - int hcrc; /* true if there was or will be a header crc */
1.125 - int done; /* true when done reading gzip header (not used
1.126 - when writing a gzip file) */
1.127 -} gz_header;
1.128 -
1.129 -typedef gz_header FAR *gz_headerp;
1.130 -
1.131 -/*
1.132 - The application must update next_in and avail_in when avail_in has
1.133 - dropped to zero. It must update next_out and avail_out when avail_out
1.134 - has dropped to zero. The application must initialize zalloc, zfree and
1.135 - opaque before calling the init function. All other fields are set by the
1.136 - compression library and must not be updated by the application.
1.137 -
1.138 - The opaque value provided by the application will be passed as the first
1.139 - parameter for calls of zalloc and zfree. This can be useful for custom
1.140 - memory management. The compression library attaches no meaning to the
1.141 - opaque value.
1.142 -
1.143 - zalloc must return Z_NULL if there is not enough memory for the object.
1.144 - If zlib is used in a multi-threaded application, zalloc and zfree must be
1.145 - thread safe.
1.146 -
1.147 - On 16-bit systems, the functions zalloc and zfree must be able to allocate
1.148 - exactly 65536 bytes, but will not be required to allocate more than this
1.149 - if the symbol MAXSEG_64K is defined (see zconf.h). WARNING: On MSDOS,
1.150 - pointers returned by zalloc for objects of exactly 65536 bytes *must*
1.151 - have their offset normalized to zero. The default allocation function
1.152 - provided by this library ensures this (see zutil.c). To reduce memory
1.153 - requirements and avoid any allocation of 64K objects, at the expense of
1.154 - compression ratio, compile the library with -DMAX_WBITS=14 (see zconf.h).
1.155 -
1.156 - The fields total_in and total_out can be used for statistics or
1.157 - progress reports. After compression, total_in holds the total size of
1.158 - the uncompressed data and may be saved for use in the decompressor
1.159 - (particularly if the decompressor wants to decompress everything in
1.160 - a single step).
1.161 -*/
1.162 -
1.163 - /* constants */
1.164 -
1.165 -#define Z_NO_FLUSH 0
1.166 -#define Z_PARTIAL_FLUSH 1 /* will be removed, use Z_SYNC_FLUSH instead */
1.167 -#define Z_SYNC_FLUSH 2
1.168 -#define Z_FULL_FLUSH 3
1.169 -#define Z_FINISH 4
1.170 -#define Z_BLOCK 5
1.171 -/* Allowed flush values; see deflate() and inflate() below for details */
1.172 -
1.173 -#define Z_OK 0
1.174 -#define Z_STREAM_END 1
1.175 -#define Z_NEED_DICT 2
1.176 -#define Z_ERRNO (-1)
1.177 -#define Z_STREAM_ERROR (-2)
1.178 -#define Z_DATA_ERROR (-3)
1.179 -#define Z_MEM_ERROR (-4)
1.180 -#define Z_BUF_ERROR (-5)
1.181 -#define Z_VERSION_ERROR (-6)
1.182 -/* Return codes for the compression/decompression functions. Negative
1.183 - * values are errors, positive values are used for special but normal events.
1.184 - */
1.185 -
1.186 -#define Z_NO_COMPRESSION 0
1.187 -#define Z_BEST_SPEED 1
1.188 -#define Z_BEST_COMPRESSION 9
1.189 -#define Z_DEFAULT_COMPRESSION (-1)
1.190 -/* compression levels */
1.191 -
1.192 -#define Z_FILTERED 1
1.193 -#define Z_HUFFMAN_ONLY 2
1.194 -#define Z_RLE 3
1.195 -#define Z_FIXED 4
1.196 -#define Z_DEFAULT_STRATEGY 0
1.197 -/* compression strategy; see deflateInit2() below for details */
1.198 -
1.199 -#define Z_BINARY 0
1.200 -#define Z_TEXT 1
1.201 -#define Z_ASCII Z_TEXT /* for compatibility with 1.2.2 and earlier */
1.202 -#define Z_UNKNOWN 2
1.203 -/* Possible values of the data_type field (though see inflate()) */
1.204 -
1.205 -#define Z_DEFLATED 8
1.206 -/* The deflate compression method (the only one supported in this version) */
1.207 -
1.208 -#define Z_NULL 0 /* for initializing zalloc, zfree, opaque */
1.209 -
1.210 -#define zlib_version zlibVersion()
1.211 -/* for compatibility with versions < 1.0.2 */
1.212 -
1.213 - /* basic functions */
1.214 -
1.215 -ZEXTERN const char * ZEXPORT zlibVersion OF((void));
1.216 -/* The application can compare zlibVersion and ZLIB_VERSION for consistency.
1.217 - If the first character differs, the library code actually used is
1.218 - not compatible with the zlib.h header file used by the application.
1.219 - This check is automatically made by deflateInit and inflateInit.
1.220 - */
1.221 -
1.222 -/*
1.223 -ZEXTERN int ZEXPORT deflateInit OF((z_streamp strm, int level));
1.224 -
1.225 - Initializes the internal stream state for compression. The fields
1.226 - zalloc, zfree and opaque must be initialized before by the caller.
1.227 - If zalloc and zfree are set to Z_NULL, deflateInit updates them to
1.228 - use default allocation functions.
1.229 -
1.230 - The compression level must be Z_DEFAULT_COMPRESSION, or between 0 and 9:
1.231 - 1 gives best speed, 9 gives best compression, 0 gives no compression at
1.232 - all (the input data is simply copied a block at a time).
1.233 - Z_DEFAULT_COMPRESSION requests a default compromise between speed and
1.234 - compression (currently equivalent to level 6).
1.235 -
1.236 - deflateInit returns Z_OK if success, Z_MEM_ERROR if there was not
1.237 - enough memory, Z_STREAM_ERROR if level is not a valid compression level,
1.238 - Z_VERSION_ERROR if the zlib library version (zlib_version) is incompatible
1.239 - with the version assumed by the caller (ZLIB_VERSION).
1.240 - msg is set to null if there is no error message. deflateInit does not
1.241 - perform any compression: this will be done by deflate().
1.242 -*/
1.243 -
1.244 -
1.245 -ZEXTERN int ZEXPORT deflate OF((z_streamp strm, int flush));
1.246 -/*
1.247 - deflate compresses as much data as possible, and stops when the input
1.248 - buffer becomes empty or the output buffer becomes full. It may introduce some
1.249 - output latency (reading input without producing any output) except when
1.250 - forced to flush.
1.251 -
1.252 - The detailed semantics are as follows. deflate performs one or both of the
1.253 - following actions:
1.254 -
1.255 - - Compress more input starting at next_in and update next_in and avail_in
1.256 - accordingly. If not all input can be processed (because there is not
1.257 - enough room in the output buffer), next_in and avail_in are updated and
1.258 - processing will resume at this point for the next call of deflate().
1.259 -
1.260 - - Provide more output starting at next_out and update next_out and avail_out
1.261 - accordingly. This action is forced if the parameter flush is non zero.
1.262 - Forcing flush frequently degrades the compression ratio, so this parameter
1.263 - should be set only when necessary (in interactive applications).
1.264 - Some output may be provided even if flush is not set.
1.265 -
1.266 - Before the call of deflate(), the application should ensure that at least
1.267 - one of the actions is possible, by providing more input and/or consuming
1.268 - more output, and updating avail_in or avail_out accordingly; avail_out
1.269 - should never be zero before the call. The application can consume the
1.270 - compressed output when it wants, for example when the output buffer is full
1.271 - (avail_out == 0), or after each call of deflate(). If deflate returns Z_OK
1.272 - and with zero avail_out, it must be called again after making room in the
1.273 - output buffer because there might be more output pending.
1.274 -
1.275 - Normally the parameter flush is set to Z_NO_FLUSH, which allows deflate to
1.276 - decide how much data to accumualte before producing output, in order to
1.277 - maximize compression.
1.278 -
1.279 - If the parameter flush is set to Z_SYNC_FLUSH, all pending output is
1.280 - flushed to the output buffer and the output is aligned on a byte boundary, so
1.281 - that the decompressor can get all input data available so far. (In particular
1.282 - avail_in is zero after the call if enough output space has been provided
1.283 - before the call.) Flushing may degrade compression for some compression
1.284 - algorithms and so it should be used only when necessary.
1.285 -
1.286 - If flush is set to Z_FULL_FLUSH, all output is flushed as with
1.287 - Z_SYNC_FLUSH, and the compression state is reset so that decompression can
1.288 - restart from this point if previous compressed data has been damaged or if
1.289 - random access is desired. Using Z_FULL_FLUSH too often can seriously degrade
1.290 - compression.
1.291 -
1.292 - If deflate returns with avail_out == 0, this function must be called again
1.293 - with the same value of the flush parameter and more output space (updated
1.294 - avail_out), until the flush is complete (deflate returns with non-zero
1.295 - avail_out). In the case of a Z_FULL_FLUSH or Z_SYNC_FLUSH, make sure that
1.296 - avail_out is greater than six to avoid repeated flush markers due to
1.297 - avail_out == 0 on return.
1.298 -
1.299 - If the parameter flush is set to Z_FINISH, pending input is processed,
1.300 - pending output is flushed and deflate returns with Z_STREAM_END if there
1.301 - was enough output space; if deflate returns with Z_OK, this function must be
1.302 - called again with Z_FINISH and more output space (updated avail_out) but no
1.303 - more input data, until it returns with Z_STREAM_END or an error. After
1.304 - deflate has returned Z_STREAM_END, the only possible operations on the
1.305 - stream are deflateReset or deflateEnd.
1.306 -
1.307 - Z_FINISH can be used immediately after deflateInit if all the compression
1.308 - is to be done in a single step. In this case, avail_out must be at least
1.309 - the value returned by deflateBound (see below). If deflate does not return
1.310 - Z_STREAM_END, then it must be called again as described above.
1.311 -
1.312 - deflate() sets strm->adler to the adler32 checksum of all input read
1.313 - so far (that is, total_in bytes).
1.314 -
1.315 - deflate() may update strm->data_type if it can make a good guess about
1.316 - the input data type (Z_BINARY or Z_TEXT). In doubt, the data is considered
1.317 - binary. This field is only for information purposes and does not affect
1.318 - the compression algorithm in any manner.
1.319 -
1.320 - deflate() returns Z_OK if some progress has been made (more input
1.321 - processed or more output produced), Z_STREAM_END if all input has been
1.322 - consumed and all output has been produced (only when flush is set to
1.323 - Z_FINISH), Z_STREAM_ERROR if the stream state was inconsistent (for example
1.324 - if next_in or next_out was NULL), Z_BUF_ERROR if no progress is possible
1.325 - (for example avail_in or avail_out was zero). Note that Z_BUF_ERROR is not
1.326 - fatal, and deflate() can be called again with more input and more output
1.327 - space to continue compressing.
1.328 -*/
1.329 -
1.330 -
1.331 -ZEXTERN int ZEXPORT deflateEnd OF((z_streamp strm));
1.332 -/*
1.333 - All dynamically allocated data structures for this stream are freed.
1.334 - This function discards any unprocessed input and does not flush any
1.335 - pending output.
1.336 -
1.337 - deflateEnd returns Z_OK if success, Z_STREAM_ERROR if the
1.338 - stream state was inconsistent, Z_DATA_ERROR if the stream was freed
1.339 - prematurely (some input or output was discarded). In the error case,
1.340 - msg may be set but then points to a static string (which must not be
1.341 - deallocated).
1.342 -*/
1.343 -
1.344 -
1.345 -/*
1.346 -ZEXTERN int ZEXPORT inflateInit OF((z_streamp strm));
1.347 -
1.348 - Initializes the internal stream state for decompression. The fields
1.349 - next_in, avail_in, zalloc, zfree and opaque must be initialized before by
1.350 - the caller. If next_in is not Z_NULL and avail_in is large enough (the exact
1.351 - value depends on the compression method), inflateInit determines the
1.352 - compression method from the zlib header and allocates all data structures
1.353 - accordingly; otherwise the allocation will be deferred to the first call of
1.354 - inflate. If zalloc and zfree are set to Z_NULL, inflateInit updates them to
1.355 - use default allocation functions.
1.356 -
1.357 - inflateInit returns Z_OK if success, Z_MEM_ERROR if there was not enough
1.358 - memory, Z_VERSION_ERROR if the zlib library version is incompatible with the
1.359 - version assumed by the caller. msg is set to null if there is no error
1.360 - message. inflateInit does not perform any decompression apart from reading
1.361 - the zlib header if present: this will be done by inflate(). (So next_in and
1.362 - avail_in may be modified, but next_out and avail_out are unchanged.)
1.363 -*/
1.364 -
1.365 -
1.366 -ZEXTERN int ZEXPORT inflate OF((z_streamp strm, int flush));
1.367 -/*
1.368 - inflate decompresses as much data as possible, and stops when the input
1.369 - buffer becomes empty or the output buffer becomes full. It may introduce
1.370 - some output latency (reading input without producing any output) except when
1.371 - forced to flush.
1.372 -
1.373 - The detailed semantics are as follows. inflate performs one or both of the
1.374 - following actions:
1.375 -
1.376 - - Decompress more input starting at next_in and update next_in and avail_in
1.377 - accordingly. If not all input can be processed (because there is not
1.378 - enough room in the output buffer), next_in is updated and processing
1.379 - will resume at this point for the next call of inflate().
1.380 -
1.381 - - Provide more output starting at next_out and update next_out and avail_out
1.382 - accordingly. inflate() provides as much output as possible, until there
1.383 - is no more input data or no more space in the output buffer (see below
1.384 - about the flush parameter).
1.385 -
1.386 - Before the call of inflate(), the application should ensure that at least
1.387 - one of the actions is possible, by providing more input and/or consuming
1.388 - more output, and updating the next_* and avail_* values accordingly.
1.389 - The application can consume the uncompressed output when it wants, for
1.390 - example when the output buffer is full (avail_out == 0), or after each
1.391 - call of inflate(). If inflate returns Z_OK and with zero avail_out, it
1.392 - must be called again after making room in the output buffer because there
1.393 - might be more output pending.
1.394 -
1.395 - The flush parameter of inflate() can be Z_NO_FLUSH, Z_SYNC_FLUSH,
1.396 - Z_FINISH, or Z_BLOCK. Z_SYNC_FLUSH requests that inflate() flush as much
1.397 - output as possible to the output buffer. Z_BLOCK requests that inflate() stop
1.398 - if and when it gets to the next deflate block boundary. When decoding the
1.399 - zlib or gzip format, this will cause inflate() to return immediately after
1.400 - the header and before the first block. When doing a raw inflate, inflate()
1.401 - will go ahead and process the first block, and will return when it gets to
1.402 - the end of that block, or when it runs out of data.
1.403 -
1.404 - The Z_BLOCK option assists in appending to or combining deflate streams.
1.405 - Also to assist in this, on return inflate() will set strm->data_type to the
1.406 - number of unused bits in the last byte taken from strm->next_in, plus 64
1.407 - if inflate() is currently decoding the last block in the deflate stream,
1.408 - plus 128 if inflate() returned immediately after decoding an end-of-block
1.409 - code or decoding the complete header up to just before the first byte of the
1.410 - deflate stream. The end-of-block will not be indicated until all of the
1.411 - uncompressed data from that block has been written to strm->next_out. The
1.412 - number of unused bits may in general be greater than seven, except when
1.413 - bit 7 of data_type is set, in which case the number of unused bits will be
1.414 - less than eight.
1.415 -
1.416 - inflate() should normally be called until it returns Z_STREAM_END or an
1.417 - error. However if all decompression is to be performed in a single step
1.418 - (a single call of inflate), the parameter flush should be set to
1.419 - Z_FINISH. In this case all pending input is processed and all pending
1.420 - output is flushed; avail_out must be large enough to hold all the
1.421 - uncompressed data. (The size of the uncompressed data may have been saved
1.422 - by the compressor for this purpose.) The next operation on this stream must
1.423 - be inflateEnd to deallocate the decompression state. The use of Z_FINISH
1.424 - is never required, but can be used to inform inflate that a faster approach
1.425 - may be used for the single inflate() call.
1.426 -
1.427 - In this implementation, inflate() always flushes as much output as
1.428 - possible to the output buffer, and always uses the faster approach on the
1.429 - first call. So the only effect of the flush parameter in this implementation
1.430 - is on the return value of inflate(), as noted below, or when it returns early
1.431 - because Z_BLOCK is used.
1.432 -
1.433 - If a preset dictionary is needed after this call (see inflateSetDictionary
1.434 - below), inflate sets strm->adler to the adler32 checksum of the dictionary
1.435 - chosen by the compressor and returns Z_NEED_DICT; otherwise it sets
1.436 - strm->adler to the adler32 checksum of all output produced so far (that is,
1.437 - total_out bytes) and returns Z_OK, Z_STREAM_END or an error code as described
1.438 - below. At the end of the stream, inflate() checks that its computed adler32
1.439 - checksum is equal to that saved by the compressor and returns Z_STREAM_END
1.440 - only if the checksum is correct.
1.441 -
1.442 - inflate() will decompress and check either zlib-wrapped or gzip-wrapped
1.443 - deflate data. The header type is detected automatically. Any information
1.444 - contained in the gzip header is not retained, so applications that need that
1.445 - information should instead use raw inflate, see inflateInit2() below, or
1.446 - inflateBack() and perform their own processing of the gzip header and
1.447 - trailer.
1.448 -
1.449 - inflate() returns Z_OK if some progress has been made (more input processed
1.450 - or more output produced), Z_STREAM_END if the end of the compressed data has
1.451 - been reached and all uncompressed output has been produced, Z_NEED_DICT if a
1.452 - preset dictionary is needed at this point, Z_DATA_ERROR if the input data was
1.453 - corrupted (input stream not conforming to the zlib format or incorrect check
1.454 - value), Z_STREAM_ERROR if the stream structure was inconsistent (for example
1.455 - if next_in or next_out was NULL), Z_MEM_ERROR if there was not enough memory,
1.456 - Z_BUF_ERROR if no progress is possible or if there was not enough room in the
1.457 - output buffer when Z_FINISH is used. Note that Z_BUF_ERROR is not fatal, and
1.458 - inflate() can be called again with more input and more output space to
1.459 - continue decompressing. If Z_DATA_ERROR is returned, the application may then
1.460 - call inflateSync() to look for a good compression block if a partial recovery
1.461 - of the data is desired.
1.462 -*/
1.463 -
1.464 -
1.465 -ZEXTERN int ZEXPORT inflateEnd OF((z_streamp strm));
1.466 -/*
1.467 - All dynamically allocated data structures for this stream are freed.
1.468 - This function discards any unprocessed input and does not flush any
1.469 - pending output.
1.470 -
1.471 - inflateEnd returns Z_OK if success, Z_STREAM_ERROR if the stream state
1.472 - was inconsistent. In the error case, msg may be set but then points to a
1.473 - static string (which must not be deallocated).
1.474 -*/
1.475 -
1.476 - /* Advanced functions */
1.477 -
1.478 -/*
1.479 - The following functions are needed only in some special applications.
1.480 -*/
1.481 -
1.482 -/*
1.483 -ZEXTERN int ZEXPORT deflateInit2 OF((z_streamp strm,
1.484 - int level,
1.485 - int method,
1.486 - int windowBits,
1.487 - int memLevel,
1.488 - int strategy));
1.489 -
1.490 - This is another version of deflateInit with more compression options. The
1.491 - fields next_in, zalloc, zfree and opaque must be initialized before by
1.492 - the caller.
1.493 -
1.494 - The method parameter is the compression method. It must be Z_DEFLATED in
1.495 - this version of the library.
1.496 -
1.497 - The windowBits parameter is the base two logarithm of the window size
1.498 - (the size of the history buffer). It should be in the range 8..15 for this
1.499 - version of the library. Larger values of this parameter result in better
1.500 - compression at the expense of memory usage. The default value is 15 if
1.501 - deflateInit is used instead.
1.502 -
1.503 - windowBits can also be -8..-15 for raw deflate. In this case, -windowBits
1.504 - determines the window size. deflate() will then generate raw deflate data
1.505 - with no zlib header or trailer, and will not compute an adler32 check value.
1.506 -
1.507 - windowBits can also be greater than 15 for optional gzip encoding. Add
1.508 - 16 to windowBits to write a simple gzip header and trailer around the
1.509 - compressed data instead of a zlib wrapper. The gzip header will have no
1.510 - file name, no extra data, no comment, no modification time (set to zero),
1.511 - no header crc, and the operating system will be set to 255 (unknown). If a
1.512 - gzip stream is being written, strm->adler is a crc32 instead of an adler32.
1.513 -
1.514 - The memLevel parameter specifies how much memory should be allocated
1.515 - for the internal compression state. memLevel=1 uses minimum memory but
1.516 - is slow and reduces compression ratio; memLevel=9 uses maximum memory
1.517 - for optimal speed. The default value is 8. See zconf.h for total memory
1.518 - usage as a function of windowBits and memLevel.
1.519 -
1.520 - The strategy parameter is used to tune the compression algorithm. Use the
1.521 - value Z_DEFAULT_STRATEGY for normal data, Z_FILTERED for data produced by a
1.522 - filter (or predictor), Z_HUFFMAN_ONLY to force Huffman encoding only (no
1.523 - string match), or Z_RLE to limit match distances to one (run-length
1.524 - encoding). Filtered data consists mostly of small values with a somewhat
1.525 - random distribution. In this case, the compression algorithm is tuned to
1.526 - compress them better. The effect of Z_FILTERED is to force more Huffman
1.527 - coding and less string matching; it is somewhat intermediate between
1.528 - Z_DEFAULT and Z_HUFFMAN_ONLY. Z_RLE is designed to be almost as fast as
1.529 - Z_HUFFMAN_ONLY, but give better compression for PNG image data. The strategy
1.530 - parameter only affects the compression ratio but not the correctness of the
1.531 - compressed output even if it is not set appropriately. Z_FIXED prevents the
1.532 - use of dynamic Huffman codes, allowing for a simpler decoder for special
1.533 - applications.
1.534 -
1.535 - deflateInit2 returns Z_OK if success, Z_MEM_ERROR if there was not enough
1.536 - memory, Z_STREAM_ERROR if a parameter is invalid (such as an invalid
1.537 - method). msg is set to null if there is no error message. deflateInit2 does
1.538 - not perform any compression: this will be done by deflate().
1.539 -*/
1.540 -
1.541 -ZEXTERN int ZEXPORT deflateSetDictionary OF((z_streamp strm,
1.542 - const Bytef *dictionary,
1.543 - uInt dictLength));
1.544 -/*
1.545 - Initializes the compression dictionary from the given byte sequence
1.546 - without producing any compressed output. This function must be called
1.547 - immediately after deflateInit, deflateInit2 or deflateReset, before any
1.548 - call of deflate. The compressor and decompressor must use exactly the same
1.549 - dictionary (see inflateSetDictionary).
1.550 -
1.551 - The dictionary should consist of strings (byte sequences) that are likely
1.552 - to be encountered later in the data to be compressed, with the most commonly
1.553 - used strings preferably put towards the end of the dictionary. Using a
1.554 - dictionary is most useful when the data to be compressed is short and can be
1.555 - predicted with good accuracy; the data can then be compressed better than
1.556 - with the default empty dictionary.
1.557 -
1.558 - Depending on the size of the compression data structures selected by
1.559 - deflateInit or deflateInit2, a part of the dictionary may in effect be
1.560 - discarded, for example if the dictionary is larger than the window size in
1.561 - deflate or deflate2. Thus the strings most likely to be useful should be
1.562 - put at the end of the dictionary, not at the front. In addition, the
1.563 - current implementation of deflate will use at most the window size minus
1.564 - 262 bytes of the provided dictionary.
1.565 -
1.566 - Upon return of this function, strm->adler is set to the adler32 value
1.567 - of the dictionary; the decompressor may later use this value to determine
1.568 - which dictionary has been used by the compressor. (The adler32 value
1.569 - applies to the whole dictionary even if only a subset of the dictionary is
1.570 - actually used by the compressor.) If a raw deflate was requested, then the
1.571 - adler32 value is not computed and strm->adler is not set.
1.572 -
1.573 - deflateSetDictionary returns Z_OK if success, or Z_STREAM_ERROR if a
1.574 - parameter is invalid (such as NULL dictionary) or the stream state is
1.575 - inconsistent (for example if deflate has already been called for this stream
1.576 - or if the compression method is bsort). deflateSetDictionary does not
1.577 - perform any compression: this will be done by deflate().
1.578 -*/
1.579 -
1.580 -ZEXTERN int ZEXPORT deflateCopy OF((z_streamp dest,
1.581 - z_streamp source));
1.582 -/*
1.583 - Sets the destination stream as a complete copy of the source stream.
1.584 -
1.585 - This function can be useful when several compression strategies will be
1.586 - tried, for example when there are several ways of pre-processing the input
1.587 - data with a filter. The streams that will be discarded should then be freed
1.588 - by calling deflateEnd. Note that deflateCopy duplicates the internal
1.589 - compression state which can be quite large, so this strategy is slow and
1.590 - can consume lots of memory.
1.591 -
1.592 - deflateCopy returns Z_OK if success, Z_MEM_ERROR if there was not
1.593 - enough memory, Z_STREAM_ERROR if the source stream state was inconsistent
1.594 - (such as zalloc being NULL). msg is left unchanged in both source and
1.595 - destination.
1.596 -*/
1.597 -
1.598 -ZEXTERN int ZEXPORT deflateReset OF((z_streamp strm));
1.599 -/*
1.600 - This function is equivalent to deflateEnd followed by deflateInit,
1.601 - but does not free and reallocate all the internal compression state.
1.602 - The stream will keep the same compression level and any other attributes
1.603 - that may have been set by deflateInit2.
1.604 -
1.605 - deflateReset returns Z_OK if success, or Z_STREAM_ERROR if the source
1.606 - stream state was inconsistent (such as zalloc or state being NULL).
1.607 -*/
1.608 -
1.609 -ZEXTERN int ZEXPORT deflateParams OF((z_streamp strm,
1.610 - int level,
1.611 - int strategy));
1.612 -/*
1.613 - Dynamically update the compression level and compression strategy. The
1.614 - interpretation of level and strategy is as in deflateInit2. This can be
1.615 - used to switch between compression and straight copy of the input data, or
1.616 - to switch to a different kind of input data requiring a different
1.617 - strategy. If the compression level is changed, the input available so far
1.618 - is compressed with the old level (and may be flushed); the new level will
1.619 - take effect only at the next call of deflate().
1.620 -
1.621 - Before the call of deflateParams, the stream state must be set as for
1.622 - a call of deflate(), since the currently available input may have to
1.623 - be compressed and flushed. In particular, strm->avail_out must be non-zero.
1.624 -
1.625 - deflateParams returns Z_OK if success, Z_STREAM_ERROR if the source
1.626 - stream state was inconsistent or if a parameter was invalid, Z_BUF_ERROR
1.627 - if strm->avail_out was zero.
1.628 -*/
1.629 -
1.630 -ZEXTERN int ZEXPORT deflateTune OF((z_streamp strm,
1.631 - int good_length,
1.632 - int max_lazy,
1.633 - int nice_length,
1.634 - int max_chain));
1.635 -/*
1.636 - Fine tune deflate's internal compression parameters. This should only be
1.637 - used by someone who understands the algorithm used by zlib's deflate for
1.638 - searching for the best matching string, and even then only by the most
1.639 - fanatic optimizer trying to squeeze out the last compressed bit for their
1.640 - specific input data. Read the deflate.c source code for the meaning of the
1.641 - max_lazy, good_length, nice_length, and max_chain parameters.
1.642 -
1.643 - deflateTune() can be called after deflateInit() or deflateInit2(), and
1.644 - returns Z_OK on success, or Z_STREAM_ERROR for an invalid deflate stream.
1.645 - */
1.646 -
1.647 -ZEXTERN uLong ZEXPORT deflateBound OF((z_streamp strm,
1.648 - uLong sourceLen));
1.649 -/*
1.650 - deflateBound() returns an upper bound on the compressed size after
1.651 - deflation of sourceLen bytes. It must be called after deflateInit()
1.652 - or deflateInit2(). This would be used to allocate an output buffer
1.653 - for deflation in a single pass, and so would be called before deflate().
1.654 -*/
1.655 -
1.656 -ZEXTERN int ZEXPORT deflatePrime OF((z_streamp strm,
1.657 - int bits,
1.658 - int value));
1.659 -/*
1.660 - deflatePrime() inserts bits in the deflate output stream. The intent
1.661 - is that this function is used to start off the deflate output with the
1.662 - bits leftover from a previous deflate stream when appending to it. As such,
1.663 - this function can only be used for raw deflate, and must be used before the
1.664 - first deflate() call after a deflateInit2() or deflateReset(). bits must be
1.665 - less than or equal to 16, and that many of the least significant bits of
1.666 - value will be inserted in the output.
1.667 -
1.668 - deflatePrime returns Z_OK if success, or Z_STREAM_ERROR if the source
1.669 - stream state was inconsistent.
1.670 -*/
1.671 -
1.672 -ZEXTERN int ZEXPORT deflateSetHeader OF((z_streamp strm,
1.673 - gz_headerp head));
1.674 -/*
1.675 - deflateSetHeader() provides gzip header information for when a gzip
1.676 - stream is requested by deflateInit2(). deflateSetHeader() may be called
1.677 - after deflateInit2() or deflateReset() and before the first call of
1.678 - deflate(). The text, time, os, extra field, name, and comment information
1.679 - in the provided gz_header structure are written to the gzip header (xflag is
1.680 - ignored -- the extra flags are set according to the compression level). The
1.681 - caller must assure that, if not Z_NULL, name and comment are terminated with
1.682 - a zero byte, and that if extra is not Z_NULL, that extra_len bytes are
1.683 - available there. If hcrc is true, a gzip header crc is included. Note that
1.684 - the current versions of the command-line version of gzip (up through version
1.685 - 1.3.x) do not support header crc's, and will report that it is a "multi-part
1.686 - gzip file" and give up.
1.687 -
1.688 - If deflateSetHeader is not used, the default gzip header has text false,
1.689 - the time set to zero, and os set to 255, with no extra, name, or comment
1.690 - fields. The gzip header is returned to the default state by deflateReset().
1.691 -
1.692 - deflateSetHeader returns Z_OK if success, or Z_STREAM_ERROR if the source
1.693 - stream state was inconsistent.
1.694 -*/
1.695 -
1.696 -/*
1.697 -ZEXTERN int ZEXPORT inflateInit2 OF((z_streamp strm,
1.698 - int windowBits));
1.699 -
1.700 - This is another version of inflateInit with an extra parameter. The
1.701 - fields next_in, avail_in, zalloc, zfree and opaque must be initialized
1.702 - before by the caller.
1.703 -
1.704 - The windowBits parameter is the base two logarithm of the maximum window
1.705 - size (the size of the history buffer). It should be in the range 8..15 for
1.706 - this version of the library. The default value is 15 if inflateInit is used
1.707 - instead. windowBits must be greater than or equal to the windowBits value
1.708 - provided to deflateInit2() while compressing, or it must be equal to 15 if
1.709 - deflateInit2() was not used. If a compressed stream with a larger window
1.710 - size is given as input, inflate() will return with the error code
1.711 - Z_DATA_ERROR instead of trying to allocate a larger window.
1.712 -
1.713 - windowBits can also be -8..-15 for raw inflate. In this case, -windowBits
1.714 - determines the window size. inflate() will then process raw deflate data,
1.715 - not looking for a zlib or gzip header, not generating a check value, and not
1.716 - looking for any check values for comparison at the end of the stream. This
1.717 - is for use with other formats that use the deflate compressed data format
1.718 - such as zip. Those formats provide their own check values. If a custom
1.719 - format is developed using the raw deflate format for compressed data, it is
1.720 - recommended that a check value such as an adler32 or a crc32 be applied to
1.721 - the uncompressed data as is done in the zlib, gzip, and zip formats. For
1.722 - most applications, the zlib format should be used as is. Note that comments
1.723 - above on the use in deflateInit2() applies to the magnitude of windowBits.
1.724 -
1.725 - windowBits can also be greater than 15 for optional gzip decoding. Add
1.726 - 32 to windowBits to enable zlib and gzip decoding with automatic header
1.727 - detection, or add 16 to decode only the gzip format (the zlib format will
1.728 - return a Z_DATA_ERROR). If a gzip stream is being decoded, strm->adler is
1.729 - a crc32 instead of an adler32.
1.730 -
1.731 - inflateInit2 returns Z_OK if success, Z_MEM_ERROR if there was not enough
1.732 - memory, Z_STREAM_ERROR if a parameter is invalid (such as a null strm). msg
1.733 - is set to null if there is no error message. inflateInit2 does not perform
1.734 - any decompression apart from reading the zlib header if present: this will
1.735 - be done by inflate(). (So next_in and avail_in may be modified, but next_out
1.736 - and avail_out are unchanged.)
1.737 -*/
1.738 -
1.739 -ZEXTERN int ZEXPORT inflateSetDictionary OF((z_streamp strm,
1.740 - const Bytef *dictionary,
1.741 - uInt dictLength));
1.742 -/*
1.743 - Initializes the decompression dictionary from the given uncompressed byte
1.744 - sequence. This function must be called immediately after a call of inflate,
1.745 - if that call returned Z_NEED_DICT. The dictionary chosen by the compressor
1.746 - can be determined from the adler32 value returned by that call of inflate.
1.747 - The compressor and decompressor must use exactly the same dictionary (see
1.748 - deflateSetDictionary). For raw inflate, this function can be called
1.749 - immediately after inflateInit2() or inflateReset() and before any call of
1.750 - inflate() to set the dictionary. The application must insure that the
1.751 - dictionary that was used for compression is provided.
1.752 -
1.753 - inflateSetDictionary returns Z_OK if success, Z_STREAM_ERROR if a
1.754 - parameter is invalid (such as NULL dictionary) or the stream state is
1.755 - inconsistent, Z_DATA_ERROR if the given dictionary doesn't match the
1.756 - expected one (incorrect adler32 value). inflateSetDictionary does not
1.757 - perform any decompression: this will be done by subsequent calls of
1.758 - inflate().
1.759 -*/
1.760 -
1.761 -ZEXTERN int ZEXPORT inflateSync OF((z_streamp strm));
1.762 -/*
1.763 - Skips invalid compressed data until a full flush point (see above the
1.764 - description of deflate with Z_FULL_FLUSH) can be found, or until all
1.765 - available input is skipped. No output is provided.
1.766 -
1.767 - inflateSync returns Z_OK if a full flush point has been found, Z_BUF_ERROR
1.768 - if no more input was provided, Z_DATA_ERROR if no flush point has been found,
1.769 - or Z_STREAM_ERROR if the stream structure was inconsistent. In the success
1.770 - case, the application may save the current current value of total_in which
1.771 - indicates where valid compressed data was found. In the error case, the
1.772 - application may repeatedly call inflateSync, providing more input each time,
1.773 - until success or end of the input data.
1.774 -*/
1.775 -
1.776 -ZEXTERN int ZEXPORT inflateCopy OF((z_streamp dest,
1.777 - z_streamp source));
1.778 -/*
1.779 - Sets the destination stream as a complete copy of the source stream.
1.780 -
1.781 - This function can be useful when randomly accessing a large stream. The
1.782 - first pass through the stream can periodically record the inflate state,
1.783 - allowing restarting inflate at those points when randomly accessing the
1.784 - stream.
1.785 -
1.786 - inflateCopy returns Z_OK if success, Z_MEM_ERROR if there was not
1.787 - enough memory, Z_STREAM_ERROR if the source stream state was inconsistent
1.788 - (such as zalloc being NULL). msg is left unchanged in both source and
1.789 - destination.
1.790 -*/
1.791 -
1.792 -ZEXTERN int ZEXPORT inflateReset OF((z_streamp strm));
1.793 -/*
1.794 - This function is equivalent to inflateEnd followed by inflateInit,
1.795 - but does not free and reallocate all the internal decompression state.
1.796 - The stream will keep attributes that may have been set by inflateInit2.
1.797 -
1.798 - inflateReset returns Z_OK if success, or Z_STREAM_ERROR if the source
1.799 - stream state was inconsistent (such as zalloc or state being NULL).
1.800 -*/
1.801 -
1.802 -ZEXTERN int ZEXPORT inflatePrime OF((z_streamp strm,
1.803 - int bits,
1.804 - int value));
1.805 -/*
1.806 - This function inserts bits in the inflate input stream. The intent is
1.807 - that this function is used to start inflating at a bit position in the
1.808 - middle of a byte. The provided bits will be used before any bytes are used
1.809 - from next_in. This function should only be used with raw inflate, and
1.810 - should be used before the first inflate() call after inflateInit2() or
1.811 - inflateReset(). bits must be less than or equal to 16, and that many of the
1.812 - least significant bits of value will be inserted in the input.
1.813 -
1.814 - inflatePrime returns Z_OK if success, or Z_STREAM_ERROR if the source
1.815 - stream state was inconsistent.
1.816 -*/
1.817 -
1.818 -ZEXTERN int ZEXPORT inflateGetHeader OF((z_streamp strm,
1.819 - gz_headerp head));
1.820 -/*
1.821 - inflateGetHeader() requests that gzip header information be stored in the
1.822 - provided gz_header structure. inflateGetHeader() may be called after
1.823 - inflateInit2() or inflateReset(), and before the first call of inflate().
1.824 - As inflate() processes the gzip stream, head->done is zero until the header
1.825 - is completed, at which time head->done is set to one. If a zlib stream is
1.826 - being decoded, then head->done is set to -1 to indicate that there will be
1.827 - no gzip header information forthcoming. Note that Z_BLOCK can be used to
1.828 - force inflate() to return immediately after header processing is complete
1.829 - and before any actual data is decompressed.
1.830 -
1.831 - The text, time, xflags, and os fields are filled in with the gzip header
1.832 - contents. hcrc is set to true if there is a header CRC. (The header CRC
1.833 - was valid if done is set to one.) If extra is not Z_NULL, then extra_max
1.834 - contains the maximum number of bytes to write to extra. Once done is true,
1.835 - extra_len contains the actual extra field length, and extra contains the
1.836 - extra field, or that field truncated if extra_max is less than extra_len.
1.837 - If name is not Z_NULL, then up to name_max characters are written there,
1.838 - terminated with a zero unless the length is greater than name_max. If
1.839 - comment is not Z_NULL, then up to comm_max characters are written there,
1.840 - terminated with a zero unless the length is greater than comm_max. When
1.841 - any of extra, name, or comment are not Z_NULL and the respective field is
1.842 - not present in the header, then that field is set to Z_NULL to signal its
1.843 - absence. This allows the use of deflateSetHeader() with the returned
1.844 - structure to duplicate the header. However if those fields are set to
1.845 - allocated memory, then the application will need to save those pointers
1.846 - elsewhere so that they can be eventually freed.
1.847 -
1.848 - If inflateGetHeader is not used, then the header information is simply
1.849 - discarded. The header is always checked for validity, including the header
1.850 - CRC if present. inflateReset() will reset the process to discard the header
1.851 - information. The application would need to call inflateGetHeader() again to
1.852 - retrieve the header from the next gzip stream.
1.853 -
1.854 - inflateGetHeader returns Z_OK if success, or Z_STREAM_ERROR if the source
1.855 - stream state was inconsistent.
1.856 -*/
1.857 -
1.858 -/*
1.859 -ZEXTERN int ZEXPORT inflateBackInit OF((z_streamp strm, int windowBits,
1.860 - unsigned char FAR *window));
1.861 -
1.862 - Initialize the internal stream state for decompression using inflateBack()
1.863 - calls. The fields zalloc, zfree and opaque in strm must be initialized
1.864 - before the call. If zalloc and zfree are Z_NULL, then the default library-
1.865 - derived memory allocation routines are used. windowBits is the base two
1.866 - logarithm of the window size, in the range 8..15. window is a caller
1.867 - supplied buffer of that size. Except for special applications where it is
1.868 - assured that deflate was used with small window sizes, windowBits must be 15
1.869 - and a 32K byte window must be supplied to be able to decompress general
1.870 - deflate streams.
1.871 -
1.872 - See inflateBack() for the usage of these routines.
1.873 -
1.874 - inflateBackInit will return Z_OK on success, Z_STREAM_ERROR if any of
1.875 - the paramaters are invalid, Z_MEM_ERROR if the internal state could not
1.876 - be allocated, or Z_VERSION_ERROR if the version of the library does not
1.877 - match the version of the header file.
1.878 -*/
1.879 -
1.880 -typedef unsigned (*in_func) OF((void FAR *, unsigned char FAR * FAR *));
1.881 -typedef int (*out_func) OF((void FAR *, unsigned char FAR *, unsigned));
1.882 -
1.883 -ZEXTERN int ZEXPORT inflateBack OF((z_streamp strm,
1.884 - in_func in, void FAR *in_desc,
1.885 - out_func out, void FAR *out_desc));
1.886 -/*
1.887 - inflateBack() does a raw inflate with a single call using a call-back
1.888 - interface for input and output. This is more efficient than inflate() for
1.889 - file i/o applications in that it avoids copying between the output and the
1.890 - sliding window by simply making the window itself the output buffer. This
1.891 - function trusts the application to not change the output buffer passed by
1.892 - the output function, at least until inflateBack() returns.
1.893 -
1.894 - inflateBackInit() must be called first to allocate the internal state
1.895 - and to initialize the state with the user-provided window buffer.
1.896 - inflateBack() may then be used multiple times to inflate a complete, raw
1.897 - deflate stream with each call. inflateBackEnd() is then called to free
1.898 - the allocated state.
1.899 -
1.900 - A raw deflate stream is one with no zlib or gzip header or trailer.
1.901 - This routine would normally be used in a utility that reads zip or gzip
1.902 - files and writes out uncompressed files. The utility would decode the
1.903 - header and process the trailer on its own, hence this routine expects
1.904 - only the raw deflate stream to decompress. This is different from the
1.905 - normal behavior of inflate(), which expects either a zlib or gzip header and
1.906 - trailer around the deflate stream.
1.907 -
1.908 - inflateBack() uses two subroutines supplied by the caller that are then
1.909 - called by inflateBack() for input and output. inflateBack() calls those
1.910 - routines until it reads a complete deflate stream and writes out all of the
1.911 - uncompressed data, or until it encounters an error. The function's
1.912 - parameters and return types are defined above in the in_func and out_func
1.913 - typedefs. inflateBack() will call in(in_desc, &buf) which should return the
1.914 - number of bytes of provided input, and a pointer to that input in buf. If
1.915 - there is no input available, in() must return zero--buf is ignored in that
1.916 - case--and inflateBack() will return a buffer error. inflateBack() will call
1.917 - out(out_desc, buf, len) to write the uncompressed data buf[0..len-1]. out()
1.918 - should return zero on success, or non-zero on failure. If out() returns
1.919 - non-zero, inflateBack() will return with an error. Neither in() nor out()
1.920 - are permitted to change the contents of the window provided to
1.921 - inflateBackInit(), which is also the buffer that out() uses to write from.
1.922 - The length written by out() will be at most the window size. Any non-zero
1.923 - amount of input may be provided by in().
1.924 -
1.925 - For convenience, inflateBack() can be provided input on the first call by
1.926 - setting strm->next_in and strm->avail_in. If that input is exhausted, then
1.927 - in() will be called. Therefore strm->next_in must be initialized before
1.928 - calling inflateBack(). If strm->next_in is Z_NULL, then in() will be called
1.929 - immediately for input. If strm->next_in is not Z_NULL, then strm->avail_in
1.930 - must also be initialized, and then if strm->avail_in is not zero, input will
1.931 - initially be taken from strm->next_in[0 .. strm->avail_in - 1].
1.932 -
1.933 - The in_desc and out_desc parameters of inflateBack() is passed as the
1.934 - first parameter of in() and out() respectively when they are called. These
1.935 - descriptors can be optionally used to pass any information that the caller-
1.936 - supplied in() and out() functions need to do their job.
1.937 -
1.938 - On return, inflateBack() will set strm->next_in and strm->avail_in to
1.939 - pass back any unused input that was provided by the last in() call. The
1.940 - return values of inflateBack() can be Z_STREAM_END on success, Z_BUF_ERROR
1.941 - if in() or out() returned an error, Z_DATA_ERROR if there was a format
1.942 - error in the deflate stream (in which case strm->msg is set to indicate the
1.943 - nature of the error), or Z_STREAM_ERROR if the stream was not properly
1.944 - initialized. In the case of Z_BUF_ERROR, an input or output error can be
1.945 - distinguished using strm->next_in which will be Z_NULL only if in() returned
1.946 - an error. If strm->next is not Z_NULL, then the Z_BUF_ERROR was due to
1.947 - out() returning non-zero. (in() will always be called before out(), so
1.948 - strm->next_in is assured to be defined if out() returns non-zero.) Note
1.949 - that inflateBack() cannot return Z_OK.
1.950 -*/
1.951 -
1.952 -ZEXTERN int ZEXPORT inflateBackEnd OF((z_streamp strm));
1.953 -/*
1.954 - All memory allocated by inflateBackInit() is freed.
1.955 -
1.956 - inflateBackEnd() returns Z_OK on success, or Z_STREAM_ERROR if the stream
1.957 - state was inconsistent.
1.958 -*/
1.959 -
1.960 -ZEXTERN uLong ZEXPORT zlibCompileFlags OF((void));
1.961 -/* Return flags indicating compile-time options.
1.962 -
1.963 - Type sizes, two bits each, 00 = 16 bits, 01 = 32, 10 = 64, 11 = other:
1.964 - 1.0: size of uInt
1.965 - 3.2: size of uLong
1.966 - 5.4: size of voidpf (pointer)
1.967 - 7.6: size of z_off_t
1.968 -
1.969 - Compiler, assembler, and debug options:
1.970 - 8: DEBUG
1.971 - 9: ASMV or ASMINF -- use ASM code
1.972 - 10: ZLIB_WINAPI -- exported functions use the WINAPI calling convention
1.973 - 11: 0 (reserved)
1.974 -
1.975 - One-time table building (smaller code, but not thread-safe if true):
1.976 - 12: BUILDFIXED -- build static block decoding tables when needed
1.977 - 13: DYNAMIC_CRC_TABLE -- build CRC calculation tables when needed
1.978 - 14,15: 0 (reserved)
1.979 -
1.980 - Library content (indicates missing functionality):
1.981 - 16: NO_GZCOMPRESS -- gz* functions cannot compress (to avoid linking
1.982 - deflate code when not needed)
1.983 - 17: NO_GZIP -- deflate can't write gzip streams, and inflate can't detect
1.984 - and decode gzip streams (to avoid linking crc code)
1.985 - 18-19: 0 (reserved)
1.986 -
1.987 - Operation variations (changes in library functionality):
1.988 - 20: PKZIP_BUG_WORKAROUND -- slightly more permissive inflate
1.989 - 21: FASTEST -- deflate algorithm with only one, lowest compression level
1.990 - 22,23: 0 (reserved)
1.991 -
1.992 - The sprintf variant used by gzprintf (zero is best):
1.993 - 24: 0 = vs*, 1 = s* -- 1 means limited to 20 arguments after the format
1.994 - 25: 0 = *nprintf, 1 = *printf -- 1 means gzprintf() not secure!
1.995 - 26: 0 = returns value, 1 = void -- 1 means inferred string length returned
1.996 -
1.997 - Remainder:
1.998 - 27-31: 0 (reserved)
1.999 - */
1.1000 -
1.1001 -
1.1002 - /* utility functions */
1.1003 -
1.1004 -/*
1.1005 - The following utility functions are implemented on top of the
1.1006 - basic stream-oriented functions. To simplify the interface, some
1.1007 - default options are assumed (compression level and memory usage,
1.1008 - standard memory allocation functions). The source code of these
1.1009 - utility functions can easily be modified if you need special options.
1.1010 -*/
1.1011 -
1.1012 -ZEXTERN int ZEXPORT compress OF((Bytef *dest, uLongf *destLen,
1.1013 - const Bytef *source, uLong sourceLen));
1.1014 -/*
1.1015 - Compresses the source buffer into the destination buffer. sourceLen is
1.1016 - the byte length of the source buffer. Upon entry, destLen is the total
1.1017 - size of the destination buffer, which must be at least the value returned
1.1018 - by compressBound(sourceLen). Upon exit, destLen is the actual size of the
1.1019 - compressed buffer.
1.1020 - This function can be used to compress a whole file at once if the
1.1021 - input file is mmap'ed.
1.1022 - compress returns Z_OK if success, Z_MEM_ERROR if there was not
1.1023 - enough memory, Z_BUF_ERROR if there was not enough room in the output
1.1024 - buffer.
1.1025 -*/
1.1026 -
1.1027 -ZEXTERN int ZEXPORT compress2 OF((Bytef *dest, uLongf *destLen,
1.1028 - const Bytef *source, uLong sourceLen,
1.1029 - int level));
1.1030 -/*
1.1031 - Compresses the source buffer into the destination buffer. The level
1.1032 - parameter has the same meaning as in deflateInit. sourceLen is the byte
1.1033 - length of the source buffer. Upon entry, destLen is the total size of the
1.1034 - destination buffer, which must be at least the value returned by
1.1035 - compressBound(sourceLen). Upon exit, destLen is the actual size of the
1.1036 - compressed buffer.
1.1037 -
1.1038 - compress2 returns Z_OK if success, Z_MEM_ERROR if there was not enough
1.1039 - memory, Z_BUF_ERROR if there was not enough room in the output buffer,
1.1040 - Z_STREAM_ERROR if the level parameter is invalid.
1.1041 -*/
1.1042 -
1.1043 -ZEXTERN uLong ZEXPORT compressBound OF((uLong sourceLen));
1.1044 -/*
1.1045 - compressBound() returns an upper bound on the compressed size after
1.1046 - compress() or compress2() on sourceLen bytes. It would be used before
1.1047 - a compress() or compress2() call to allocate the destination buffer.
1.1048 -*/
1.1049 -
1.1050 -ZEXTERN int ZEXPORT uncompress OF((Bytef *dest, uLongf *destLen,
1.1051 - const Bytef *source, uLong sourceLen));
1.1052 -/*
1.1053 - Decompresses the source buffer into the destination buffer. sourceLen is
1.1054 - the byte length of the source buffer. Upon entry, destLen is the total
1.1055 - size of the destination buffer, which must be large enough to hold the
1.1056 - entire uncompressed data. (The size of the uncompressed data must have
1.1057 - been saved previously by the compressor and transmitted to the decompressor
1.1058 - by some mechanism outside the scope of this compression library.)
1.1059 - Upon exit, destLen is the actual size of the compressed buffer.
1.1060 - This function can be used to decompress a whole file at once if the
1.1061 - input file is mmap'ed.
1.1062 -
1.1063 - uncompress returns Z_OK if success, Z_MEM_ERROR if there was not
1.1064 - enough memory, Z_BUF_ERROR if there was not enough room in the output
1.1065 - buffer, or Z_DATA_ERROR if the input data was corrupted or incomplete.
1.1066 -*/
1.1067 -
1.1068 -
1.1069 -typedef voidp gzFile;
1.1070 -
1.1071 -ZEXTERN gzFile ZEXPORT gzopen OF((const char *path, const char *mode));
1.1072 -/*
1.1073 - Opens a gzip (.gz) file for reading or writing. The mode parameter
1.1074 - is as in fopen ("rb" or "wb") but can also include a compression level
1.1075 - ("wb9") or a strategy: 'f' for filtered data as in "wb6f", 'h' for
1.1076 - Huffman only compression as in "wb1h", or 'R' for run-length encoding
1.1077 - as in "wb1R". (See the description of deflateInit2 for more information
1.1078 - about the strategy parameter.)
1.1079 -
1.1080 - gzopen can be used to read a file which is not in gzip format; in this
1.1081 - case gzread will directly read from the file without decompression.
1.1082 -
1.1083 - gzopen returns NULL if the file could not be opened or if there was
1.1084 - insufficient memory to allocate the (de)compression state; errno
1.1085 - can be checked to distinguish the two cases (if errno is zero, the
1.1086 - zlib error is Z_MEM_ERROR). */
1.1087 -
1.1088 -ZEXTERN gzFile ZEXPORT gzdopen OF((int fd, const char *mode));
1.1089 -/*
1.1090 - gzdopen() associates a gzFile with the file descriptor fd. File
1.1091 - descriptors are obtained from calls like open, dup, creat, pipe or
1.1092 - fileno (in the file has been previously opened with fopen).
1.1093 - The mode parameter is as in gzopen.
1.1094 - The next call of gzclose on the returned gzFile will also close the
1.1095 - file descriptor fd, just like fclose(fdopen(fd), mode) closes the file
1.1096 - descriptor fd. If you want to keep fd open, use gzdopen(dup(fd), mode).
1.1097 - gzdopen returns NULL if there was insufficient memory to allocate
1.1098 - the (de)compression state.
1.1099 -*/
1.1100 -
1.1101 -ZEXTERN int ZEXPORT gzsetparams OF((gzFile file, int level, int strategy));
1.1102 -/*
1.1103 - Dynamically update the compression level or strategy. See the description
1.1104 - of deflateInit2 for the meaning of these parameters.
1.1105 - gzsetparams returns Z_OK if success, or Z_STREAM_ERROR if the file was not
1.1106 - opened for writing.
1.1107 -*/
1.1108 -
1.1109 -ZEXTERN int ZEXPORT gzread OF((gzFile file, voidp buf, unsigned len));
1.1110 -/*
1.1111 - Reads the given number of uncompressed bytes from the compressed file.
1.1112 - If the input file was not in gzip format, gzread copies the given number
1.1113 - of bytes into the buffer.
1.1114 - gzread returns the number of uncompressed bytes actually read (0 for
1.1115 - end of file, -1 for error). */
1.1116 -
1.1117 -ZEXTERN int ZEXPORT gzwrite OF((gzFile file,
1.1118 - voidpc buf, unsigned len));
1.1119 -/*
1.1120 - Writes the given number of uncompressed bytes into the compressed file.
1.1121 - gzwrite returns the number of uncompressed bytes actually written
1.1122 - (0 in case of error).
1.1123 -*/
1.1124 -
1.1125 -ZEXTERN int ZEXPORTVA gzprintf OF((gzFile file, const char *format, ...));
1.1126 -/*
1.1127 - Converts, formats, and writes the args to the compressed file under
1.1128 - control of the format string, as in fprintf. gzprintf returns the number of
1.1129 - uncompressed bytes actually written (0 in case of error). The number of
1.1130 - uncompressed bytes written is limited to 4095. The caller should assure that
1.1131 - this limit is not exceeded. If it is exceeded, then gzprintf() will return
1.1132 - return an error (0) with nothing written. In this case, there may also be a
1.1133 - buffer overflow with unpredictable consequences, which is possible only if
1.1134 - zlib was compiled with the insecure functions sprintf() or vsprintf()
1.1135 - because the secure snprintf() or vsnprintf() functions were not available.
1.1136 -*/
1.1137 -
1.1138 -ZEXTERN int ZEXPORT gzputs OF((gzFile file, const char *s));
1.1139 -/*
1.1140 - Writes the given null-terminated string to the compressed file, excluding
1.1141 - the terminating null character.
1.1142 - gzputs returns the number of characters written, or -1 in case of error.
1.1143 -*/
1.1144 -
1.1145 -ZEXTERN char * ZEXPORT gzgets OF((gzFile file, char *buf, int len));
1.1146 -/*
1.1147 - Reads bytes from the compressed file until len-1 characters are read, or
1.1148 - a newline character is read and transferred to buf, or an end-of-file
1.1149 - condition is encountered. The string is then terminated with a null
1.1150 - character.
1.1151 - gzgets returns buf, or Z_NULL in case of error.
1.1152 -*/
1.1153 -
1.1154 -ZEXTERN int ZEXPORT gzputc OF((gzFile file, int c));
1.1155 -/*
1.1156 - Writes c, converted to an unsigned char, into the compressed file.
1.1157 - gzputc returns the value that was written, or -1 in case of error.
1.1158 -*/
1.1159 -
1.1160 -ZEXTERN int ZEXPORT gzgetc OF((gzFile file));
1.1161 -/*
1.1162 - Reads one byte from the compressed file. gzgetc returns this byte
1.1163 - or -1 in case of end of file or error.
1.1164 -*/
1.1165 -
1.1166 -ZEXTERN int ZEXPORT gzungetc OF((int c, gzFile file));
1.1167 -/*
1.1168 - Push one character back onto the stream to be read again later.
1.1169 - Only one character of push-back is allowed. gzungetc() returns the
1.1170 - character pushed, or -1 on failure. gzungetc() will fail if a
1.1171 - character has been pushed but not read yet, or if c is -1. The pushed
1.1172 - character will be discarded if the stream is repositioned with gzseek()
1.1173 - or gzrewind().
1.1174 -*/
1.1175 -
1.1176 -ZEXTERN int ZEXPORT gzflush OF((gzFile file, int flush));
1.1177 -/*
1.1178 - Flushes all pending output into the compressed file. The parameter
1.1179 - flush is as in the deflate() function. The return value is the zlib
1.1180 - error number (see function gzerror below). gzflush returns Z_OK if
1.1181 - the flush parameter is Z_FINISH and all output could be flushed.
1.1182 - gzflush should be called only when strictly necessary because it can
1.1183 - degrade compression.
1.1184 -*/
1.1185 -
1.1186 -ZEXTERN z_off_t ZEXPORT gzseek OF((gzFile file,
1.1187 - z_off_t offset, int whence));
1.1188 -/*
1.1189 - Sets the starting position for the next gzread or gzwrite on the
1.1190 - given compressed file. The offset represents a number of bytes in the
1.1191 - uncompressed data stream. The whence parameter is defined as in lseek(2);
1.1192 - the value SEEK_END is not supported.
1.1193 - If the file is opened for reading, this function is emulated but can be
1.1194 - extremely slow. If the file is opened for writing, only forward seeks are
1.1195 - supported; gzseek then compresses a sequence of zeroes up to the new
1.1196 - starting position.
1.1197 -
1.1198 - gzseek returns the resulting offset location as measured in bytes from
1.1199 - the beginning of the uncompressed stream, or -1 in case of error, in
1.1200 - particular if the file is opened for writing and the new starting position
1.1201 - would be before the current position.
1.1202 -*/
1.1203 -
1.1204 -ZEXTERN int ZEXPORT gzrewind OF((gzFile file));
1.1205 -/*
1.1206 - Rewinds the given file. This function is supported only for reading.
1.1207 -
1.1208 - gzrewind(file) is equivalent to (int)gzseek(file, 0L, SEEK_SET)
1.1209 -*/
1.1210 -
1.1211 -ZEXTERN z_off_t ZEXPORT gztell OF((gzFile file));
1.1212 -/*
1.1213 - Returns the starting position for the next gzread or gzwrite on the
1.1214 - given compressed file. This position represents a number of bytes in the
1.1215 - uncompressed data stream.
1.1216 -
1.1217 - gztell(file) is equivalent to gzseek(file, 0L, SEEK_CUR)
1.1218 -*/
1.1219 -
1.1220 -ZEXTERN int ZEXPORT gzeof OF((gzFile file));
1.1221 -/*
1.1222 - Returns 1 when EOF has previously been detected reading the given
1.1223 - input stream, otherwise zero.
1.1224 -*/
1.1225 -
1.1226 -ZEXTERN int ZEXPORT gzdirect OF((gzFile file));
1.1227 -/*
1.1228 - Returns 1 if file is being read directly without decompression, otherwise
1.1229 - zero.
1.1230 -*/
1.1231 -
1.1232 -ZEXTERN int ZEXPORT gzclose OF((gzFile file));
1.1233 -/*
1.1234 - Flushes all pending output if necessary, closes the compressed file
1.1235 - and deallocates all the (de)compression state. The return value is the zlib
1.1236 - error number (see function gzerror below).
1.1237 -*/
1.1238 -
1.1239 -ZEXTERN const char * ZEXPORT gzerror OF((gzFile file, int *errnum));
1.1240 -/*
1.1241 - Returns the error message for the last error which occurred on the
1.1242 - given compressed file. errnum is set to zlib error number. If an
1.1243 - error occurred in the file system and not in the compression library,
1.1244 - errnum is set to Z_ERRNO and the application may consult errno
1.1245 - to get the exact error code.
1.1246 -*/
1.1247 -
1.1248 -ZEXTERN void ZEXPORT gzclearerr OF((gzFile file));
1.1249 -/*
1.1250 - Clears the error and end-of-file flags for file. This is analogous to the
1.1251 - clearerr() function in stdio. This is useful for continuing to read a gzip
1.1252 - file that is being written concurrently.
1.1253 -*/
1.1254 -
1.1255 - /* checksum functions */
1.1256 -
1.1257 -/*
1.1258 - These functions are not related to compression but are exported
1.1259 - anyway because they might be useful in applications using the
1.1260 - compression library.
1.1261 -*/
1.1262 -
1.1263 -ZEXTERN uLong ZEXPORT adler32 OF((uLong adler, const Bytef *buf, uInt len));
1.1264 -/*
1.1265 - Update a running Adler-32 checksum with the bytes buf[0..len-1] and
1.1266 - return the updated checksum. If buf is NULL, this function returns
1.1267 - the required initial value for the checksum.
1.1268 - An Adler-32 checksum is almost as reliable as a CRC32 but can be computed
1.1269 - much faster. Usage example:
1.1270 -
1.1271 - uLong adler = adler32(0L, Z_NULL, 0);
1.1272 -
1.1273 - while (read_buffer(buffer, length) != EOF) {
1.1274 - adler = adler32(adler, buffer, length);
1.1275 - }
1.1276 - if (adler != original_adler) error();
1.1277 -*/
1.1278 -
1.1279 -ZEXTERN uLong ZEXPORT adler32_combine OF((uLong adler1, uLong adler2,
1.1280 - z_off_t len2));
1.1281 -/*
1.1282 - Combine two Adler-32 checksums into one. For two sequences of bytes, seq1
1.1283 - and seq2 with lengths len1 and len2, Adler-32 checksums were calculated for
1.1284 - each, adler1 and adler2. adler32_combine() returns the Adler-32 checksum of
1.1285 - seq1 and seq2 concatenated, requiring only adler1, adler2, and len2.
1.1286 -*/
1.1287 -
1.1288 -ZEXTERN uLong ZEXPORT crc32 OF((uLong crc, const Bytef *buf, uInt len));
1.1289 -/*
1.1290 - Update a running CRC-32 with the bytes buf[0..len-1] and return the
1.1291 - updated CRC-32. If buf is NULL, this function returns the required initial
1.1292 - value for the for the crc. Pre- and post-conditioning (one's complement) is
1.1293 - performed within this function so it shouldn't be done by the application.
1.1294 - Usage example:
1.1295 -
1.1296 - uLong crc = crc32(0L, Z_NULL, 0);
1.1297 -
1.1298 - while (read_buffer(buffer, length) != EOF) {
1.1299 - crc = crc32(crc, buffer, length);
1.1300 - }
1.1301 - if (crc != original_crc) error();
1.1302 -*/
1.1303 -
1.1304 -ZEXTERN uLong ZEXPORT crc32_combine OF((uLong crc1, uLong crc2, z_off_t len2));
1.1305 -
1.1306 -/*
1.1307 - Combine two CRC-32 check values into one. For two sequences of bytes,
1.1308 - seq1 and seq2 with lengths len1 and len2, CRC-32 check values were
1.1309 - calculated for each, crc1 and crc2. crc32_combine() returns the CRC-32
1.1310 - check value of seq1 and seq2 concatenated, requiring only crc1, crc2, and
1.1311 - len2.
1.1312 -*/
1.1313 -
1.1314 -
1.1315 - /* various hacks, don't look :) */
1.1316 -
1.1317 -/* deflateInit and inflateInit are macros to allow checking the zlib version
1.1318 - * and the compiler's view of z_stream:
1.1319 - */
1.1320 -ZEXTERN int ZEXPORT deflateInit_ OF((z_streamp strm, int level,
1.1321 - const char *version, int stream_size));
1.1322 -ZEXTERN int ZEXPORT inflateInit_ OF((z_streamp strm,
1.1323 - const char *version, int stream_size));
1.1324 -ZEXTERN int ZEXPORT deflateInit2_ OF((z_streamp strm, int level, int method,
1.1325 - int windowBits, int memLevel,
1.1326 - int strategy, const char *version,
1.1327 - int stream_size));
1.1328 -ZEXTERN int ZEXPORT inflateInit2_ OF((z_streamp strm, int windowBits,
1.1329 - const char *version, int stream_size));
1.1330 -ZEXTERN int ZEXPORT inflateBackInit_ OF((z_streamp strm, int windowBits,
1.1331 - unsigned char FAR *window,
1.1332 - const char *version,
1.1333 - int stream_size));
1.1334 -#define deflateInit(strm, level) \
1.1335 - deflateInit_((strm), (level), ZLIB_VERSION, sizeof(z_stream))
1.1336 -#define inflateInit(strm) \
1.1337 - inflateInit_((strm), ZLIB_VERSION, sizeof(z_stream))
1.1338 -#define deflateInit2(strm, level, method, windowBits, memLevel, strategy) \
1.1339 - deflateInit2_((strm),(level),(method),(windowBits),(memLevel),\
1.1340 - (strategy), ZLIB_VERSION, sizeof(z_stream))
1.1341 -#define inflateInit2(strm, windowBits) \
1.1342 - inflateInit2_((strm), (windowBits), ZLIB_VERSION, sizeof(z_stream))
1.1343 -#define inflateBackInit(strm, windowBits, window) \
1.1344 - inflateBackInit_((strm), (windowBits), (window), \
1.1345 - ZLIB_VERSION, sizeof(z_stream))
1.1346 -
1.1347 -
1.1348 -#if !defined(ZUTIL_H) && !defined(NO_DUMMY_DECL)
1.1349 - struct internal_state {int dummy;}; /* hack for buggy compilers */
1.1350 -#endif
1.1351 -
1.1352 -ZEXTERN const char * ZEXPORT zError OF((int));
1.1353 -ZEXTERN int ZEXPORT inflateSyncPoint OF((z_streamp z));
1.1354 -ZEXTERN const uLongf * ZEXPORT get_crc_table OF((void));
1.1355 -
1.1356 -#ifdef __cplusplus
1.1357 -}
1.1358 -#endif
1.1359 -
1.1360 -#endif /* ZLIB_H */
