1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/compiler-init/zlib/zlib.h Sat Jul 15 04:51:28 2006 +0000
1.3 @@ -0,0 +1,1357 @@
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 */
