1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/modules/zlib/src/zlib.h Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,1769 @@
1.4 +/* zlib.h -- interface of the 'zlib' general purpose compression library
1.5 + version 1.2.8, April 28th, 2013
1.6 +
1.7 + Copyright (C) 1995-2013 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 + jloup@gzip.org madler@alumni.caltech.edu
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://tools.ietf.org/html/rfc1950
1.31 + (zlib format), rfc1951 (deflate format) and rfc1952 (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 "1.2.8"
1.44 +#define ZLIB_VERNUM 0x1280
1.45 +#define ZLIB_VER_MAJOR 1
1.46 +#define ZLIB_VER_MINOR 2
1.47 +#define ZLIB_VER_REVISION 8
1.48 +#define ZLIB_VER_SUBREVISION 0
1.49 +
1.50 +/*
1.51 + The 'zlib' compression library provides in-memory compression and
1.52 + decompression functions, including integrity checks of the uncompressed data.
1.53 + This version of the library supports only one compression method (deflation)
1.54 + but other algorithms will be added later and will have the same stream
1.55 + interface.
1.56 +
1.57 + Compression can be done in a single step if the buffers are large enough,
1.58 + or can be done by repeated calls of the compression function. In the latter
1.59 + case, the application must provide more input and/or consume the output
1.60 + (providing more output space) before each call.
1.61 +
1.62 + The compressed data format used by default by the in-memory functions is
1.63 + the zlib format, which is a zlib wrapper documented in RFC 1950, wrapped
1.64 + around a deflate stream, which is itself documented in RFC 1951.
1.65 +
1.66 + The library also supports reading and writing files in gzip (.gz) format
1.67 + with an interface similar to that of stdio using the functions that start
1.68 + with "gz". The gzip format is different from the zlib format. gzip is a
1.69 + gzip wrapper, documented in RFC 1952, wrapped around a deflate stream.
1.70 +
1.71 + This library can optionally read and write gzip streams in memory as well.
1.72 +
1.73 + The zlib format was designed to be compact and fast for use in memory
1.74 + and on communications channels. The gzip format was designed for single-
1.75 + file compression on file systems, has a larger header than zlib to maintain
1.76 + directory information, and uses a different, slower check method than zlib.
1.77 +
1.78 + The library does not install any signal handler. The decoder checks
1.79 + the consistency of the compressed data, so the library should never crash
1.80 + even in case of corrupted input.
1.81 +*/
1.82 +
1.83 +typedef voidpf (*alloc_func) OF((voidpf opaque, uInt items, uInt size));
1.84 +typedef void (*free_func) OF((voidpf opaque, voidpf address));
1.85 +
1.86 +struct internal_state;
1.87 +
1.88 +typedef struct z_stream_s {
1.89 + z_const Bytef *next_in; /* next input byte */
1.90 + uInt avail_in; /* number of bytes available at next_in */
1.91 + uLong total_in; /* total number of input bytes read so far */
1.92 +
1.93 + Bytef *next_out; /* next output byte should be put there */
1.94 + uInt avail_out; /* remaining free space at next_out */
1.95 + uLong total_out; /* total number of bytes output so far */
1.96 +
1.97 + z_const char *msg; /* last error message, NULL if no error */
1.98 + struct internal_state FAR *state; /* not visible by applications */
1.99 +
1.100 + alloc_func zalloc; /* used to allocate the internal state */
1.101 + free_func zfree; /* used to free the internal state */
1.102 + voidpf opaque; /* private data object passed to zalloc and zfree */
1.103 +
1.104 + int data_type; /* best guess about the data type: binary or text */
1.105 + uLong adler; /* adler32 value of the uncompressed data */
1.106 + uLong reserved; /* reserved for future use */
1.107 +} z_stream;
1.108 +
1.109 +typedef z_stream FAR *z_streamp;
1.110 +
1.111 +/*
1.112 + gzip header information passed to and from zlib routines. See RFC 1952
1.113 + for more details on the meanings of these fields.
1.114 +*/
1.115 +typedef struct gz_header_s {
1.116 + int text; /* true if compressed data believed to be text */
1.117 + uLong time; /* modification time */
1.118 + int xflags; /* extra flags (not used when writing a gzip file) */
1.119 + int os; /* operating system */
1.120 + Bytef *extra; /* pointer to extra field or Z_NULL if none */
1.121 + uInt extra_len; /* extra field length (valid if extra != Z_NULL) */
1.122 + uInt extra_max; /* space at extra (only when reading header) */
1.123 + Bytef *name; /* pointer to zero-terminated file name or Z_NULL */
1.124 + uInt name_max; /* space at name (only when reading header) */
1.125 + Bytef *comment; /* pointer to zero-terminated comment or Z_NULL */
1.126 + uInt comm_max; /* space at comment (only when reading header) */
1.127 + int hcrc; /* true if there was or will be a header crc */
1.128 + int done; /* true when done reading gzip header (not used
1.129 + when writing a gzip file) */
1.130 +} gz_header;
1.131 +
1.132 +typedef gz_header FAR *gz_headerp;
1.133 +
1.134 +/*
1.135 + The application must update next_in and avail_in when avail_in has dropped
1.136 + to zero. It must update next_out and avail_out when avail_out has dropped
1.137 + to zero. The application must initialize zalloc, zfree and opaque before
1.138 + calling the init function. All other fields are set by the compression
1.139 + library and must not be updated by the application.
1.140 +
1.141 + The opaque value provided by the application will be passed as the first
1.142 + parameter for calls of zalloc and zfree. This can be useful for custom
1.143 + memory management. The compression library attaches no meaning to the
1.144 + opaque value.
1.145 +
1.146 + zalloc must return Z_NULL if there is not enough memory for the object.
1.147 + If zlib is used in a multi-threaded application, zalloc and zfree must be
1.148 + thread safe.
1.149 +
1.150 + On 16-bit systems, the functions zalloc and zfree must be able to allocate
1.151 + exactly 65536 bytes, but will not be required to allocate more than this if
1.152 + the symbol MAXSEG_64K is defined (see zconf.h). WARNING: On MSDOS, pointers
1.153 + returned by zalloc for objects of exactly 65536 bytes *must* have their
1.154 + offset normalized to zero. The default allocation function provided by this
1.155 + library ensures this (see zutil.c). To reduce memory requirements and avoid
1.156 + any allocation of 64K objects, at the expense of compression ratio, compile
1.157 + the library with -DMAX_WBITS=14 (see zconf.h).
1.158 +
1.159 + The fields total_in and total_out can be used for statistics or progress
1.160 + reports. After compression, total_in holds the total size of the
1.161 + uncompressed data and may be saved for use in the decompressor (particularly
1.162 + if the decompressor wants to decompress everything in a single step).
1.163 +*/
1.164 +
1.165 + /* constants */
1.166 +
1.167 +#define Z_NO_FLUSH 0
1.168 +#define Z_PARTIAL_FLUSH 1
1.169 +#define Z_SYNC_FLUSH 2
1.170 +#define Z_FULL_FLUSH 3
1.171 +#define Z_FINISH 4
1.172 +#define Z_BLOCK 5
1.173 +#define Z_TREES 6
1.174 +/* Allowed flush values; see deflate() and inflate() below for details */
1.175 +
1.176 +#define Z_OK 0
1.177 +#define Z_STREAM_END 1
1.178 +#define Z_NEED_DICT 2
1.179 +#define Z_ERRNO (-1)
1.180 +#define Z_STREAM_ERROR (-2)
1.181 +#define Z_DATA_ERROR (-3)
1.182 +#define Z_MEM_ERROR (-4)
1.183 +#define Z_BUF_ERROR (-5)
1.184 +#define Z_VERSION_ERROR (-6)
1.185 +/* Return codes for the compression/decompression functions. Negative values
1.186 + * are errors, positive values are used for special but normal events.
1.187 + */
1.188 +
1.189 +#define Z_NO_COMPRESSION 0
1.190 +#define Z_BEST_SPEED 1
1.191 +#define Z_BEST_COMPRESSION 9
1.192 +#define Z_DEFAULT_COMPRESSION (-1)
1.193 +/* compression levels */
1.194 +
1.195 +#define Z_FILTERED 1
1.196 +#define Z_HUFFMAN_ONLY 2
1.197 +#define Z_RLE 3
1.198 +#define Z_FIXED 4
1.199 +#define Z_DEFAULT_STRATEGY 0
1.200 +/* compression strategy; see deflateInit2() below for details */
1.201 +
1.202 +#define Z_BINARY 0
1.203 +#define Z_TEXT 1
1.204 +#define Z_ASCII Z_TEXT /* for compatibility with 1.2.2 and earlier */
1.205 +#define Z_UNKNOWN 2
1.206 +/* Possible values of the data_type field (though see inflate()) */
1.207 +
1.208 +#define Z_DEFLATED 8
1.209 +/* The deflate compression method (the only one supported in this version) */
1.210 +
1.211 +#define Z_NULL 0 /* for initializing zalloc, zfree, opaque */
1.212 +
1.213 +#define zlib_version zlibVersion()
1.214 +/* for compatibility with versions < 1.0.2 */
1.215 +
1.216 +
1.217 + /* basic functions */
1.218 +
1.219 +ZEXTERN const char * ZEXPORT zlibVersion OF((void));
1.220 +/* The application can compare zlibVersion and ZLIB_VERSION for consistency.
1.221 + If the first character differs, the library code actually used is not
1.222 + compatible with the zlib.h header file used by the application. This check
1.223 + is automatically made by deflateInit and inflateInit.
1.224 + */
1.225 +
1.226 +/*
1.227 +ZEXTERN int ZEXPORT deflateInit OF((z_streamp strm, int level));
1.228 +
1.229 + Initializes the internal stream state for compression. The fields
1.230 + zalloc, zfree and opaque must be initialized before by the caller. If
1.231 + zalloc and zfree are set to Z_NULL, deflateInit updates them to use default
1.232 + allocation functions.
1.233 +
1.234 + The compression level must be Z_DEFAULT_COMPRESSION, or between 0 and 9:
1.235 + 1 gives best speed, 9 gives best compression, 0 gives no compression at all
1.236 + (the input data is simply copied a block at a time). Z_DEFAULT_COMPRESSION
1.237 + requests a default compromise between speed and compression (currently
1.238 + equivalent to level 6).
1.239 +
1.240 + deflateInit returns Z_OK if success, Z_MEM_ERROR if there was not enough
1.241 + memory, Z_STREAM_ERROR if level is not a valid compression level, or
1.242 + Z_VERSION_ERROR if the zlib library version (zlib_version) is incompatible
1.243 + with the version assumed by the caller (ZLIB_VERSION). msg is set to null
1.244 + if there is no error message. deflateInit does not perform any compression:
1.245 + this will be done by deflate().
1.246 +*/
1.247 +
1.248 +
1.249 +ZEXTERN int ZEXPORT deflate OF((z_streamp strm, int flush));
1.250 +/*
1.251 + deflate compresses as much data as possible, and stops when the input
1.252 + buffer becomes empty or the output buffer becomes full. It may introduce
1.253 + some output latency (reading input without producing any output) except when
1.254 + forced to flush.
1.255 +
1.256 + The detailed semantics are as follows. deflate performs one or both of the
1.257 + following actions:
1.258 +
1.259 + - Compress more input starting at next_in and update next_in and avail_in
1.260 + accordingly. If not all input can be processed (because there is not
1.261 + enough room in the output buffer), next_in and avail_in are updated and
1.262 + processing will resume at this point for the next call of deflate().
1.263 +
1.264 + - Provide more output starting at next_out and update next_out and avail_out
1.265 + accordingly. This action is forced if the parameter flush is non zero.
1.266 + Forcing flush frequently degrades the compression ratio, so this parameter
1.267 + should be set only when necessary (in interactive applications). Some
1.268 + output may be provided even if flush is not set.
1.269 +
1.270 + Before the call of deflate(), the application should ensure that at least
1.271 + one of the actions is possible, by providing more input and/or consuming more
1.272 + output, and updating avail_in or avail_out accordingly; avail_out should
1.273 + never be zero before the call. The application can consume the compressed
1.274 + output when it wants, for example when the output buffer is full (avail_out
1.275 + == 0), or after each call of deflate(). If deflate returns Z_OK and with
1.276 + zero avail_out, it must be called again after making room in the output
1.277 + buffer because there might be more output pending.
1.278 +
1.279 + Normally the parameter flush is set to Z_NO_FLUSH, which allows deflate to
1.280 + decide how much data to accumulate before producing output, in order to
1.281 + maximize compression.
1.282 +
1.283 + If the parameter flush is set to Z_SYNC_FLUSH, all pending output is
1.284 + flushed to the output buffer and the output is aligned on a byte boundary, so
1.285 + that the decompressor can get all input data available so far. (In
1.286 + particular avail_in is zero after the call if enough output space has been
1.287 + provided before the call.) Flushing may degrade compression for some
1.288 + compression algorithms and so it should be used only when necessary. This
1.289 + completes the current deflate block and follows it with an empty stored block
1.290 + that is three bits plus filler bits to the next byte, followed by four bytes
1.291 + (00 00 ff ff).
1.292 +
1.293 + If flush is set to Z_PARTIAL_FLUSH, all pending output is flushed to the
1.294 + output buffer, but the output is not aligned to a byte boundary. All of the
1.295 + input data so far will be available to the decompressor, as for Z_SYNC_FLUSH.
1.296 + This completes the current deflate block and follows it with an empty fixed
1.297 + codes block that is 10 bits long. This assures that enough bytes are output
1.298 + in order for the decompressor to finish the block before the empty fixed code
1.299 + block.
1.300 +
1.301 + If flush is set to Z_BLOCK, a deflate block is completed and emitted, as
1.302 + for Z_SYNC_FLUSH, but the output is not aligned on a byte boundary, and up to
1.303 + seven bits of the current block are held to be written as the next byte after
1.304 + the next deflate block is completed. In this case, the decompressor may not
1.305 + be provided enough bits at this point in order to complete decompression of
1.306 + the data provided so far to the compressor. It may need to wait for the next
1.307 + block to be emitted. This is for advanced applications that need to control
1.308 + the emission of deflate blocks.
1.309 +
1.310 + If flush is set to Z_FULL_FLUSH, all output is flushed as with
1.311 + Z_SYNC_FLUSH, and the compression state is reset so that decompression can
1.312 + restart from this point if previous compressed data has been damaged or if
1.313 + random access is desired. Using Z_FULL_FLUSH too often can seriously degrade
1.314 + compression.
1.315 +
1.316 + If deflate returns with avail_out == 0, this function must be called again
1.317 + with the same value of the flush parameter and more output space (updated
1.318 + avail_out), until the flush is complete (deflate returns with non-zero
1.319 + avail_out). In the case of a Z_FULL_FLUSH or Z_SYNC_FLUSH, make sure that
1.320 + avail_out is greater than six to avoid repeated flush markers due to
1.321 + avail_out == 0 on return.
1.322 +
1.323 + If the parameter flush is set to Z_FINISH, pending input is processed,
1.324 + pending output is flushed and deflate returns with Z_STREAM_END if there was
1.325 + enough output space; if deflate returns with Z_OK, this function must be
1.326 + called again with Z_FINISH and more output space (updated avail_out) but no
1.327 + more input data, until it returns with Z_STREAM_END or an error. After
1.328 + deflate has returned Z_STREAM_END, the only possible operations on the stream
1.329 + are deflateReset or deflateEnd.
1.330 +
1.331 + Z_FINISH can be used immediately after deflateInit if all the compression
1.332 + is to be done in a single step. In this case, avail_out must be at least the
1.333 + value returned by deflateBound (see below). Then deflate is guaranteed to
1.334 + return Z_STREAM_END. If not enough output space is provided, deflate will
1.335 + not return Z_STREAM_END, and it must be called again as described above.
1.336 +
1.337 + deflate() sets strm->adler to the adler32 checksum of all input read
1.338 + so far (that is, total_in bytes).
1.339 +
1.340 + deflate() may update strm->data_type if it can make a good guess about
1.341 + the input data type (Z_BINARY or Z_TEXT). In doubt, the data is considered
1.342 + binary. This field is only for information purposes and does not affect the
1.343 + compression algorithm in any manner.
1.344 +
1.345 + deflate() returns Z_OK if some progress has been made (more input
1.346 + processed or more output produced), Z_STREAM_END if all input has been
1.347 + consumed and all output has been produced (only when flush is set to
1.348 + Z_FINISH), Z_STREAM_ERROR if the stream state was inconsistent (for example
1.349 + if next_in or next_out was Z_NULL), Z_BUF_ERROR if no progress is possible
1.350 + (for example avail_in or avail_out was zero). Note that Z_BUF_ERROR is not
1.351 + fatal, and deflate() can be called again with more input and more output
1.352 + space to continue compressing.
1.353 +*/
1.354 +
1.355 +
1.356 +ZEXTERN int ZEXPORT deflateEnd OF((z_streamp strm));
1.357 +/*
1.358 + All dynamically allocated data structures for this stream are freed.
1.359 + This function discards any unprocessed input and does not flush any pending
1.360 + output.
1.361 +
1.362 + deflateEnd returns Z_OK if success, Z_STREAM_ERROR if the
1.363 + stream state was inconsistent, Z_DATA_ERROR if the stream was freed
1.364 + prematurely (some input or output was discarded). In the error case, msg
1.365 + may be set but then points to a static string (which must not be
1.366 + deallocated).
1.367 +*/
1.368 +
1.369 +
1.370 +/*
1.371 +ZEXTERN int ZEXPORT inflateInit OF((z_streamp strm));
1.372 +
1.373 + Initializes the internal stream state for decompression. The fields
1.374 + next_in, avail_in, zalloc, zfree and opaque must be initialized before by
1.375 + the caller. If next_in is not Z_NULL and avail_in is large enough (the
1.376 + exact value depends on the compression method), inflateInit determines the
1.377 + compression method from the zlib header and allocates all data structures
1.378 + accordingly; otherwise the allocation will be deferred to the first call of
1.379 + inflate. If zalloc and zfree are set to Z_NULL, inflateInit updates them to
1.380 + use default allocation functions.
1.381 +
1.382 + inflateInit returns Z_OK if success, Z_MEM_ERROR if there was not enough
1.383 + memory, Z_VERSION_ERROR if the zlib library version is incompatible with the
1.384 + version assumed by the caller, or Z_STREAM_ERROR if the parameters are
1.385 + invalid, such as a null pointer to the structure. msg is set to null if
1.386 + there is no error message. inflateInit does not perform any decompression
1.387 + apart from possibly reading the zlib header if present: actual decompression
1.388 + will be done by inflate(). (So next_in and avail_in may be modified, but
1.389 + next_out and avail_out are unused and unchanged.) The current implementation
1.390 + of inflateInit() does not process any header information -- that is deferred
1.391 + until inflate() is called.
1.392 +*/
1.393 +
1.394 +
1.395 +ZEXTERN int ZEXPORT inflate OF((z_streamp strm, int flush));
1.396 +/*
1.397 + inflate decompresses as much data as possible, and stops when the input
1.398 + buffer becomes empty or the output buffer becomes full. It may introduce
1.399 + some output latency (reading input without producing any output) except when
1.400 + forced to flush.
1.401 +
1.402 + The detailed semantics are as follows. inflate performs one or both of the
1.403 + following actions:
1.404 +
1.405 + - Decompress more input starting at next_in and update next_in and avail_in
1.406 + accordingly. If not all input can be processed (because there is not
1.407 + enough room in the output buffer), next_in is updated and processing will
1.408 + resume at this point for the next call of inflate().
1.409 +
1.410 + - Provide more output starting at next_out and update next_out and avail_out
1.411 + accordingly. inflate() provides as much output as possible, until there is
1.412 + no more input data or no more space in the output buffer (see below about
1.413 + the flush parameter).
1.414 +
1.415 + Before the call of inflate(), the application should ensure that at least
1.416 + one of the actions is possible, by providing more input and/or consuming more
1.417 + output, and updating the next_* and avail_* values accordingly. The
1.418 + application can consume the uncompressed output when it wants, for example
1.419 + when the output buffer is full (avail_out == 0), or after each call of
1.420 + inflate(). If inflate returns Z_OK and with zero avail_out, it must be
1.421 + called again after making room in the output buffer because there might be
1.422 + more output pending.
1.423 +
1.424 + The flush parameter of inflate() can be Z_NO_FLUSH, Z_SYNC_FLUSH, Z_FINISH,
1.425 + Z_BLOCK, or Z_TREES. Z_SYNC_FLUSH requests that inflate() flush as much
1.426 + output as possible to the output buffer. Z_BLOCK requests that inflate()
1.427 + stop if and when it gets to the next deflate block boundary. When decoding
1.428 + the zlib or gzip format, this will cause inflate() to return immediately
1.429 + after the header and before the first block. When doing a raw inflate,
1.430 + inflate() will go ahead and process the first block, and will return when it
1.431 + gets to the end of that block, or when it runs out of data.
1.432 +
1.433 + The Z_BLOCK option assists in appending to or combining deflate streams.
1.434 + Also to assist in this, on return inflate() will set strm->data_type to the
1.435 + number of unused bits in the last byte taken from strm->next_in, plus 64 if
1.436 + inflate() is currently decoding the last block in the deflate stream, plus
1.437 + 128 if inflate() returned immediately after decoding an end-of-block code or
1.438 + decoding the complete header up to just before the first byte of the deflate
1.439 + stream. The end-of-block will not be indicated until all of the uncompressed
1.440 + data from that block has been written to strm->next_out. The number of
1.441 + unused bits may in general be greater than seven, except when bit 7 of
1.442 + data_type is set, in which case the number of unused bits will be less than
1.443 + eight. data_type is set as noted here every time inflate() returns for all
1.444 + flush options, and so can be used to determine the amount of currently
1.445 + consumed input in bits.
1.446 +
1.447 + The Z_TREES option behaves as Z_BLOCK does, but it also returns when the
1.448 + end of each deflate block header is reached, before any actual data in that
1.449 + block is decoded. This allows the caller to determine the length of the
1.450 + deflate block header for later use in random access within a deflate block.
1.451 + 256 is added to the value of strm->data_type when inflate() returns
1.452 + immediately after reaching the end of the deflate block header.
1.453 +
1.454 + inflate() should normally be called until it returns Z_STREAM_END or an
1.455 + error. However if all decompression is to be performed in a single step (a
1.456 + single call of inflate), the parameter flush should be set to Z_FINISH. In
1.457 + this case all pending input is processed and all pending output is flushed;
1.458 + avail_out must be large enough to hold all of the uncompressed data for the
1.459 + operation to complete. (The size of the uncompressed data may have been
1.460 + saved by the compressor for this purpose.) The use of Z_FINISH is not
1.461 + required to perform an inflation in one step. However it may be used to
1.462 + inform inflate that a faster approach can be used for the single inflate()
1.463 + call. Z_FINISH also informs inflate to not maintain a sliding window if the
1.464 + stream completes, which reduces inflate's memory footprint. If the stream
1.465 + does not complete, either because not all of the stream is provided or not
1.466 + enough output space is provided, then a sliding window will be allocated and
1.467 + inflate() can be called again to continue the operation as if Z_NO_FLUSH had
1.468 + been used.
1.469 +
1.470 + In this implementation, inflate() always flushes as much output as
1.471 + possible to the output buffer, and always uses the faster approach on the
1.472 + first call. So the effects of the flush parameter in this implementation are
1.473 + on the return value of inflate() as noted below, when inflate() returns early
1.474 + when Z_BLOCK or Z_TREES is used, and when inflate() avoids the allocation of
1.475 + memory for a sliding window when Z_FINISH is used.
1.476 +
1.477 + If a preset dictionary is needed after this call (see inflateSetDictionary
1.478 + below), inflate sets strm->adler to the Adler-32 checksum of the dictionary
1.479 + chosen by the compressor and returns Z_NEED_DICT; otherwise it sets
1.480 + strm->adler to the Adler-32 checksum of all output produced so far (that is,
1.481 + total_out bytes) and returns Z_OK, Z_STREAM_END or an error code as described
1.482 + below. At the end of the stream, inflate() checks that its computed adler32
1.483 + checksum is equal to that saved by the compressor and returns Z_STREAM_END
1.484 + only if the checksum is correct.
1.485 +
1.486 + inflate() can decompress and check either zlib-wrapped or gzip-wrapped
1.487 + deflate data. The header type is detected automatically, if requested when
1.488 + initializing with inflateInit2(). Any information contained in the gzip
1.489 + header is not retained, so applications that need that information should
1.490 + instead use raw inflate, see inflateInit2() below, or inflateBack() and
1.491 + perform their own processing of the gzip header and trailer. When processing
1.492 + gzip-wrapped deflate data, strm->adler32 is set to the CRC-32 of the output
1.493 + producted so far. The CRC-32 is checked against the gzip trailer.
1.494 +
1.495 + inflate() returns Z_OK if some progress has been made (more input processed
1.496 + or more output produced), Z_STREAM_END if the end of the compressed data has
1.497 + been reached and all uncompressed output has been produced, Z_NEED_DICT if a
1.498 + preset dictionary is needed at this point, Z_DATA_ERROR if the input data was
1.499 + corrupted (input stream not conforming to the zlib format or incorrect check
1.500 + value), Z_STREAM_ERROR if the stream structure was inconsistent (for example
1.501 + next_in or next_out was Z_NULL), Z_MEM_ERROR if there was not enough memory,
1.502 + Z_BUF_ERROR if no progress is possible or if there was not enough room in the
1.503 + output buffer when Z_FINISH is used. Note that Z_BUF_ERROR is not fatal, and
1.504 + inflate() can be called again with more input and more output space to
1.505 + continue decompressing. If Z_DATA_ERROR is returned, the application may
1.506 + then call inflateSync() to look for a good compression block if a partial
1.507 + recovery of the data is desired.
1.508 +*/
1.509 +
1.510 +
1.511 +ZEXTERN int ZEXPORT inflateEnd OF((z_streamp strm));
1.512 +/*
1.513 + All dynamically allocated data structures for this stream are freed.
1.514 + This function discards any unprocessed input and does not flush any pending
1.515 + output.
1.516 +
1.517 + inflateEnd returns Z_OK if success, Z_STREAM_ERROR if the stream state
1.518 + was inconsistent. In the error case, msg may be set but then points to a
1.519 + static string (which must not be deallocated).
1.520 +*/
1.521 +
1.522 +
1.523 + /* Advanced functions */
1.524 +
1.525 +/*
1.526 + The following functions are needed only in some special applications.
1.527 +*/
1.528 +
1.529 +/*
1.530 +ZEXTERN int ZEXPORT deflateInit2 OF((z_streamp strm,
1.531 + int level,
1.532 + int method,
1.533 + int windowBits,
1.534 + int memLevel,
1.535 + int strategy));
1.536 +
1.537 + This is another version of deflateInit with more compression options. The
1.538 + fields next_in, zalloc, zfree and opaque must be initialized before by the
1.539 + caller.
1.540 +
1.541 + The method parameter is the compression method. It must be Z_DEFLATED in
1.542 + this version of the library.
1.543 +
1.544 + The windowBits parameter is the base two logarithm of the window size
1.545 + (the size of the history buffer). It should be in the range 8..15 for this
1.546 + version of the library. Larger values of this parameter result in better
1.547 + compression at the expense of memory usage. The default value is 15 if
1.548 + deflateInit is used instead.
1.549 +
1.550 + windowBits can also be -8..-15 for raw deflate. In this case, -windowBits
1.551 + determines the window size. deflate() will then generate raw deflate data
1.552 + with no zlib header or trailer, and will not compute an adler32 check value.
1.553 +
1.554 + windowBits can also be greater than 15 for optional gzip encoding. Add
1.555 + 16 to windowBits to write a simple gzip header and trailer around the
1.556 + compressed data instead of a zlib wrapper. The gzip header will have no
1.557 + file name, no extra data, no comment, no modification time (set to zero), no
1.558 + header crc, and the operating system will be set to 255 (unknown). If a
1.559 + gzip stream is being written, strm->adler is a crc32 instead of an adler32.
1.560 +
1.561 + The memLevel parameter specifies how much memory should be allocated
1.562 + for the internal compression state. memLevel=1 uses minimum memory but is
1.563 + slow and reduces compression ratio; memLevel=9 uses maximum memory for
1.564 + optimal speed. The default value is 8. See zconf.h for total memory usage
1.565 + as a function of windowBits and memLevel.
1.566 +
1.567 + The strategy parameter is used to tune the compression algorithm. Use the
1.568 + value Z_DEFAULT_STRATEGY for normal data, Z_FILTERED for data produced by a
1.569 + filter (or predictor), Z_HUFFMAN_ONLY to force Huffman encoding only (no
1.570 + string match), or Z_RLE to limit match distances to one (run-length
1.571 + encoding). Filtered data consists mostly of small values with a somewhat
1.572 + random distribution. In this case, the compression algorithm is tuned to
1.573 + compress them better. The effect of Z_FILTERED is to force more Huffman
1.574 + coding and less string matching; it is somewhat intermediate between
1.575 + Z_DEFAULT_STRATEGY and Z_HUFFMAN_ONLY. Z_RLE is designed to be almost as
1.576 + fast as Z_HUFFMAN_ONLY, but give better compression for PNG image data. The
1.577 + strategy parameter only affects the compression ratio but not the
1.578 + correctness of the compressed output even if it is not set appropriately.
1.579 + Z_FIXED prevents the use of dynamic Huffman codes, allowing for a simpler
1.580 + decoder for special applications.
1.581 +
1.582 + deflateInit2 returns Z_OK if success, Z_MEM_ERROR if there was not enough
1.583 + memory, Z_STREAM_ERROR if any parameter is invalid (such as an invalid
1.584 + method), or Z_VERSION_ERROR if the zlib library version (zlib_version) is
1.585 + incompatible with the version assumed by the caller (ZLIB_VERSION). msg is
1.586 + set to null if there is no error message. deflateInit2 does not perform any
1.587 + compression: this will be done by deflate().
1.588 +*/
1.589 +
1.590 +ZEXTERN int ZEXPORT deflateSetDictionary OF((z_streamp strm,
1.591 + const Bytef *dictionary,
1.592 + uInt dictLength));
1.593 +/*
1.594 + Initializes the compression dictionary from the given byte sequence
1.595 + without producing any compressed output. When using the zlib format, this
1.596 + function must be called immediately after deflateInit, deflateInit2 or
1.597 + deflateReset, and before any call of deflate. When doing raw deflate, this
1.598 + function must be called either before any call of deflate, or immediately
1.599 + after the completion of a deflate block, i.e. after all input has been
1.600 + consumed and all output has been delivered when using any of the flush
1.601 + options Z_BLOCK, Z_PARTIAL_FLUSH, Z_SYNC_FLUSH, or Z_FULL_FLUSH. The
1.602 + compressor and decompressor must use exactly the same dictionary (see
1.603 + inflateSetDictionary).
1.604 +
1.605 + The dictionary should consist of strings (byte sequences) that are likely
1.606 + to be encountered later in the data to be compressed, with the most commonly
1.607 + used strings preferably put towards the end of the dictionary. Using a
1.608 + dictionary is most useful when the data to be compressed is short and can be
1.609 + predicted with good accuracy; the data can then be compressed better than
1.610 + with the default empty dictionary.
1.611 +
1.612 + Depending on the size of the compression data structures selected by
1.613 + deflateInit or deflateInit2, a part of the dictionary may in effect be
1.614 + discarded, for example if the dictionary is larger than the window size
1.615 + provided in deflateInit or deflateInit2. Thus the strings most likely to be
1.616 + useful should be put at the end of the dictionary, not at the front. In
1.617 + addition, the current implementation of deflate will use at most the window
1.618 + size minus 262 bytes of the provided dictionary.
1.619 +
1.620 + Upon return of this function, strm->adler is set to the adler32 value
1.621 + of the dictionary; the decompressor may later use this value to determine
1.622 + which dictionary has been used by the compressor. (The adler32 value
1.623 + applies to the whole dictionary even if only a subset of the dictionary is
1.624 + actually used by the compressor.) If a raw deflate was requested, then the
1.625 + adler32 value is not computed and strm->adler is not set.
1.626 +
1.627 + deflateSetDictionary returns Z_OK if success, or Z_STREAM_ERROR if a
1.628 + parameter is invalid (e.g. dictionary being Z_NULL) or the stream state is
1.629 + inconsistent (for example if deflate has already been called for this stream
1.630 + or if not at a block boundary for raw deflate). deflateSetDictionary does
1.631 + not perform any compression: this will be done by deflate().
1.632 +*/
1.633 +
1.634 +ZEXTERN int ZEXPORT deflateCopy OF((z_streamp dest,
1.635 + z_streamp source));
1.636 +/*
1.637 + Sets the destination stream as a complete copy of the source stream.
1.638 +
1.639 + This function can be useful when several compression strategies will be
1.640 + tried, for example when there are several ways of pre-processing the input
1.641 + data with a filter. The streams that will be discarded should then be freed
1.642 + by calling deflateEnd. Note that deflateCopy duplicates the internal
1.643 + compression state which can be quite large, so this strategy is slow and can
1.644 + consume lots of memory.
1.645 +
1.646 + deflateCopy returns Z_OK if success, Z_MEM_ERROR if there was not
1.647 + enough memory, Z_STREAM_ERROR if the source stream state was inconsistent
1.648 + (such as zalloc being Z_NULL). msg is left unchanged in both source and
1.649 + destination.
1.650 +*/
1.651 +
1.652 +ZEXTERN int ZEXPORT deflateReset OF((z_streamp strm));
1.653 +/*
1.654 + This function is equivalent to deflateEnd followed by deflateInit,
1.655 + but does not free and reallocate all the internal compression state. The
1.656 + stream will keep the same compression level and any other attributes that
1.657 + may have been set by deflateInit2.
1.658 +
1.659 + deflateReset returns Z_OK if success, or Z_STREAM_ERROR if the source
1.660 + stream state was inconsistent (such as zalloc or state being Z_NULL).
1.661 +*/
1.662 +
1.663 +ZEXTERN int ZEXPORT deflateParams OF((z_streamp strm,
1.664 + int level,
1.665 + int strategy));
1.666 +/*
1.667 + Dynamically update the compression level and compression strategy. The
1.668 + interpretation of level and strategy is as in deflateInit2. This can be
1.669 + used to switch between compression and straight copy of the input data, or
1.670 + to switch to a different kind of input data requiring a different strategy.
1.671 + If the compression level is changed, the input available so far is
1.672 + compressed with the old level (and may be flushed); the new level will take
1.673 + effect only at the next call of deflate().
1.674 +
1.675 + Before the call of deflateParams, the stream state must be set as for
1.676 + a call of deflate(), since the currently available input may have to be
1.677 + compressed and flushed. In particular, strm->avail_out must be non-zero.
1.678 +
1.679 + deflateParams returns Z_OK if success, Z_STREAM_ERROR if the source
1.680 + stream state was inconsistent or if a parameter was invalid, Z_BUF_ERROR if
1.681 + strm->avail_out was zero.
1.682 +*/
1.683 +
1.684 +ZEXTERN int ZEXPORT deflateTune OF((z_streamp strm,
1.685 + int good_length,
1.686 + int max_lazy,
1.687 + int nice_length,
1.688 + int max_chain));
1.689 +/*
1.690 + Fine tune deflate's internal compression parameters. This should only be
1.691 + used by someone who understands the algorithm used by zlib's deflate for
1.692 + searching for the best matching string, and even then only by the most
1.693 + fanatic optimizer trying to squeeze out the last compressed bit for their
1.694 + specific input data. Read the deflate.c source code for the meaning of the
1.695 + max_lazy, good_length, nice_length, and max_chain parameters.
1.696 +
1.697 + deflateTune() can be called after deflateInit() or deflateInit2(), and
1.698 + returns Z_OK on success, or Z_STREAM_ERROR for an invalid deflate stream.
1.699 + */
1.700 +
1.701 +ZEXTERN uLong ZEXPORT deflateBound OF((z_streamp strm,
1.702 + uLong sourceLen));
1.703 +/*
1.704 + deflateBound() returns an upper bound on the compressed size after
1.705 + deflation of sourceLen bytes. It must be called after deflateInit() or
1.706 + deflateInit2(), and after deflateSetHeader(), if used. This would be used
1.707 + to allocate an output buffer for deflation in a single pass, and so would be
1.708 + called before deflate(). If that first deflate() call is provided the
1.709 + sourceLen input bytes, an output buffer allocated to the size returned by
1.710 + deflateBound(), and the flush value Z_FINISH, then deflate() is guaranteed
1.711 + to return Z_STREAM_END. Note that it is possible for the compressed size to
1.712 + be larger than the value returned by deflateBound() if flush options other
1.713 + than Z_FINISH or Z_NO_FLUSH are used.
1.714 +*/
1.715 +
1.716 +ZEXTERN int ZEXPORT deflatePending OF((z_streamp strm,
1.717 + unsigned *pending,
1.718 + int *bits));
1.719 +/*
1.720 + deflatePending() returns the number of bytes and bits of output that have
1.721 + been generated, but not yet provided in the available output. The bytes not
1.722 + provided would be due to the available output space having being consumed.
1.723 + The number of bits of output not provided are between 0 and 7, where they
1.724 + await more bits to join them in order to fill out a full byte. If pending
1.725 + or bits are Z_NULL, then those values are not set.
1.726 +
1.727 + deflatePending returns Z_OK if success, or Z_STREAM_ERROR if the source
1.728 + stream state was inconsistent.
1.729 + */
1.730 +
1.731 +ZEXTERN int ZEXPORT deflatePrime OF((z_streamp strm,
1.732 + int bits,
1.733 + int value));
1.734 +/*
1.735 + deflatePrime() inserts bits in the deflate output stream. The intent
1.736 + is that this function is used to start off the deflate output with the bits
1.737 + leftover from a previous deflate stream when appending to it. As such, this
1.738 + function can only be used for raw deflate, and must be used before the first
1.739 + deflate() call after a deflateInit2() or deflateReset(). bits must be less
1.740 + than or equal to 16, and that many of the least significant bits of value
1.741 + will be inserted in the output.
1.742 +
1.743 + deflatePrime returns Z_OK if success, Z_BUF_ERROR if there was not enough
1.744 + room in the internal buffer to insert the bits, or Z_STREAM_ERROR if the
1.745 + source stream state was inconsistent.
1.746 +*/
1.747 +
1.748 +ZEXTERN int ZEXPORT deflateSetHeader OF((z_streamp strm,
1.749 + gz_headerp head));
1.750 +/*
1.751 + deflateSetHeader() provides gzip header information for when a gzip
1.752 + stream is requested by deflateInit2(). deflateSetHeader() may be called
1.753 + after deflateInit2() or deflateReset() and before the first call of
1.754 + deflate(). The text, time, os, extra field, name, and comment information
1.755 + in the provided gz_header structure are written to the gzip header (xflag is
1.756 + ignored -- the extra flags are set according to the compression level). The
1.757 + caller must assure that, if not Z_NULL, name and comment are terminated with
1.758 + a zero byte, and that if extra is not Z_NULL, that extra_len bytes are
1.759 + available there. If hcrc is true, a gzip header crc is included. Note that
1.760 + the current versions of the command-line version of gzip (up through version
1.761 + 1.3.x) do not support header crc's, and will report that it is a "multi-part
1.762 + gzip file" and give up.
1.763 +
1.764 + If deflateSetHeader is not used, the default gzip header has text false,
1.765 + the time set to zero, and os set to 255, with no extra, name, or comment
1.766 + fields. The gzip header is returned to the default state by deflateReset().
1.767 +
1.768 + deflateSetHeader returns Z_OK if success, or Z_STREAM_ERROR if the source
1.769 + stream state was inconsistent.
1.770 +*/
1.771 +
1.772 +/*
1.773 +ZEXTERN int ZEXPORT inflateInit2 OF((z_streamp strm,
1.774 + int windowBits));
1.775 +
1.776 + This is another version of inflateInit with an extra parameter. The
1.777 + fields next_in, avail_in, zalloc, zfree and opaque must be initialized
1.778 + before by the caller.
1.779 +
1.780 + The windowBits parameter is the base two logarithm of the maximum window
1.781 + size (the size of the history buffer). It should be in the range 8..15 for
1.782 + this version of the library. The default value is 15 if inflateInit is used
1.783 + instead. windowBits must be greater than or equal to the windowBits value
1.784 + provided to deflateInit2() while compressing, or it must be equal to 15 if
1.785 + deflateInit2() was not used. If a compressed stream with a larger window
1.786 + size is given as input, inflate() will return with the error code
1.787 + Z_DATA_ERROR instead of trying to allocate a larger window.
1.788 +
1.789 + windowBits can also be zero to request that inflate use the window size in
1.790 + the zlib header of the compressed stream.
1.791 +
1.792 + windowBits can also be -8..-15 for raw inflate. In this case, -windowBits
1.793 + determines the window size. inflate() will then process raw deflate data,
1.794 + not looking for a zlib or gzip header, not generating a check value, and not
1.795 + looking for any check values for comparison at the end of the stream. This
1.796 + is for use with other formats that use the deflate compressed data format
1.797 + such as zip. Those formats provide their own check values. If a custom
1.798 + format is developed using the raw deflate format for compressed data, it is
1.799 + recommended that a check value such as an adler32 or a crc32 be applied to
1.800 + the uncompressed data as is done in the zlib, gzip, and zip formats. For
1.801 + most applications, the zlib format should be used as is. Note that comments
1.802 + above on the use in deflateInit2() applies to the magnitude of windowBits.
1.803 +
1.804 + windowBits can also be greater than 15 for optional gzip decoding. Add
1.805 + 32 to windowBits to enable zlib and gzip decoding with automatic header
1.806 + detection, or add 16 to decode only the gzip format (the zlib format will
1.807 + return a Z_DATA_ERROR). If a gzip stream is being decoded, strm->adler is a
1.808 + crc32 instead of an adler32.
1.809 +
1.810 + inflateInit2 returns Z_OK if success, Z_MEM_ERROR if there was not enough
1.811 + memory, Z_VERSION_ERROR if the zlib library version is incompatible with the
1.812 + version assumed by the caller, or Z_STREAM_ERROR if the parameters are
1.813 + invalid, such as a null pointer to the structure. msg is set to null if
1.814 + there is no error message. inflateInit2 does not perform any decompression
1.815 + apart from possibly reading the zlib header if present: actual decompression
1.816 + will be done by inflate(). (So next_in and avail_in may be modified, but
1.817 + next_out and avail_out are unused and unchanged.) The current implementation
1.818 + of inflateInit2() does not process any header information -- that is
1.819 + deferred until inflate() is called.
1.820 +*/
1.821 +
1.822 +ZEXTERN int ZEXPORT inflateSetDictionary OF((z_streamp strm,
1.823 + const Bytef *dictionary,
1.824 + uInt dictLength));
1.825 +/*
1.826 + Initializes the decompression dictionary from the given uncompressed byte
1.827 + sequence. This function must be called immediately after a call of inflate,
1.828 + if that call returned Z_NEED_DICT. The dictionary chosen by the compressor
1.829 + can be determined from the adler32 value returned by that call of inflate.
1.830 + The compressor and decompressor must use exactly the same dictionary (see
1.831 + deflateSetDictionary). For raw inflate, this function can be called at any
1.832 + time to set the dictionary. If the provided dictionary is smaller than the
1.833 + window and there is already data in the window, then the provided dictionary
1.834 + will amend what's there. The application must insure that the dictionary
1.835 + that was used for compression is provided.
1.836 +
1.837 + inflateSetDictionary returns Z_OK if success, Z_STREAM_ERROR if a
1.838 + parameter is invalid (e.g. dictionary being Z_NULL) or the stream state is
1.839 + inconsistent, Z_DATA_ERROR if the given dictionary doesn't match the
1.840 + expected one (incorrect adler32 value). inflateSetDictionary does not
1.841 + perform any decompression: this will be done by subsequent calls of
1.842 + inflate().
1.843 +*/
1.844 +
1.845 +ZEXTERN int ZEXPORT inflateGetDictionary OF((z_streamp strm,
1.846 + Bytef *dictionary,
1.847 + uInt *dictLength));
1.848 +/*
1.849 + Returns the sliding dictionary being maintained by inflate. dictLength is
1.850 + set to the number of bytes in the dictionary, and that many bytes are copied
1.851 + to dictionary. dictionary must have enough space, where 32768 bytes is
1.852 + always enough. If inflateGetDictionary() is called with dictionary equal to
1.853 + Z_NULL, then only the dictionary length is returned, and nothing is copied.
1.854 + Similary, if dictLength is Z_NULL, then it is not set.
1.855 +
1.856 + inflateGetDictionary returns Z_OK on success, or Z_STREAM_ERROR if the
1.857 + stream state is inconsistent.
1.858 +*/
1.859 +
1.860 +ZEXTERN int ZEXPORT inflateSync OF((z_streamp strm));
1.861 +/*
1.862 + Skips invalid compressed data until a possible full flush point (see above
1.863 + for the description of deflate with Z_FULL_FLUSH) can be found, or until all
1.864 + available input is skipped. No output is provided.
1.865 +
1.866 + inflateSync searches for a 00 00 FF FF pattern in the compressed data.
1.867 + All full flush points have this pattern, but not all occurrences of this
1.868 + pattern are full flush points.
1.869 +
1.870 + inflateSync returns Z_OK if a possible full flush point has been found,
1.871 + Z_BUF_ERROR if no more input was provided, Z_DATA_ERROR if no flush point
1.872 + has been found, or Z_STREAM_ERROR if the stream structure was inconsistent.
1.873 + In the success case, the application may save the current current value of
1.874 + total_in which indicates where valid compressed data was found. In the
1.875 + error case, the application may repeatedly call inflateSync, providing more
1.876 + input each time, until success or end of the input data.
1.877 +*/
1.878 +
1.879 +ZEXTERN int ZEXPORT inflateCopy OF((z_streamp dest,
1.880 + z_streamp source));
1.881 +/*
1.882 + Sets the destination stream as a complete copy of the source stream.
1.883 +
1.884 + This function can be useful when randomly accessing a large stream. The
1.885 + first pass through the stream can periodically record the inflate state,
1.886 + allowing restarting inflate at those points when randomly accessing the
1.887 + stream.
1.888 +
1.889 + inflateCopy returns Z_OK if success, Z_MEM_ERROR if there was not
1.890 + enough memory, Z_STREAM_ERROR if the source stream state was inconsistent
1.891 + (such as zalloc being Z_NULL). msg is left unchanged in both source and
1.892 + destination.
1.893 +*/
1.894 +
1.895 +ZEXTERN int ZEXPORT inflateReset OF((z_streamp strm));
1.896 +/*
1.897 + This function is equivalent to inflateEnd followed by inflateInit,
1.898 + but does not free and reallocate all the internal decompression state. The
1.899 + stream will keep attributes that may have been set by inflateInit2.
1.900 +
1.901 + inflateReset returns Z_OK if success, or Z_STREAM_ERROR if the source
1.902 + stream state was inconsistent (such as zalloc or state being Z_NULL).
1.903 +*/
1.904 +
1.905 +ZEXTERN int ZEXPORT inflateReset2 OF((z_streamp strm,
1.906 + int windowBits));
1.907 +/*
1.908 + This function is the same as inflateReset, but it also permits changing
1.909 + the wrap and window size requests. The windowBits parameter is interpreted
1.910 + the same as it is for inflateInit2.
1.911 +
1.912 + inflateReset2 returns Z_OK if success, or Z_STREAM_ERROR if the source
1.913 + stream state was inconsistent (such as zalloc or state being Z_NULL), or if
1.914 + the windowBits parameter is invalid.
1.915 +*/
1.916 +
1.917 +ZEXTERN int ZEXPORT inflatePrime OF((z_streamp strm,
1.918 + int bits,
1.919 + int value));
1.920 +/*
1.921 + This function inserts bits in the inflate input stream. The intent is
1.922 + that this function is used to start inflating at a bit position in the
1.923 + middle of a byte. The provided bits will be used before any bytes are used
1.924 + from next_in. This function should only be used with raw inflate, and
1.925 + should be used before the first inflate() call after inflateInit2() or
1.926 + inflateReset(). bits must be less than or equal to 16, and that many of the
1.927 + least significant bits of value will be inserted in the input.
1.928 +
1.929 + If bits is negative, then the input stream bit buffer is emptied. Then
1.930 + inflatePrime() can be called again to put bits in the buffer. This is used
1.931 + to clear out bits leftover after feeding inflate a block description prior
1.932 + to feeding inflate codes.
1.933 +
1.934 + inflatePrime returns Z_OK if success, or Z_STREAM_ERROR if the source
1.935 + stream state was inconsistent.
1.936 +*/
1.937 +
1.938 +ZEXTERN long ZEXPORT inflateMark OF((z_streamp strm));
1.939 +/*
1.940 + This function returns two values, one in the lower 16 bits of the return
1.941 + value, and the other in the remaining upper bits, obtained by shifting the
1.942 + return value down 16 bits. If the upper value is -1 and the lower value is
1.943 + zero, then inflate() is currently decoding information outside of a block.
1.944 + If the upper value is -1 and the lower value is non-zero, then inflate is in
1.945 + the middle of a stored block, with the lower value equaling the number of
1.946 + bytes from the input remaining to copy. If the upper value is not -1, then
1.947 + it is the number of bits back from the current bit position in the input of
1.948 + the code (literal or length/distance pair) currently being processed. In
1.949 + that case the lower value is the number of bytes already emitted for that
1.950 + code.
1.951 +
1.952 + A code is being processed if inflate is waiting for more input to complete
1.953 + decoding of the code, or if it has completed decoding but is waiting for
1.954 + more output space to write the literal or match data.
1.955 +
1.956 + inflateMark() is used to mark locations in the input data for random
1.957 + access, which may be at bit positions, and to note those cases where the
1.958 + output of a code may span boundaries of random access blocks. The current
1.959 + location in the input stream can be determined from avail_in and data_type
1.960 + as noted in the description for the Z_BLOCK flush parameter for inflate.
1.961 +
1.962 + inflateMark returns the value noted above or -1 << 16 if the provided
1.963 + source stream state was inconsistent.
1.964 +*/
1.965 +
1.966 +ZEXTERN int ZEXPORT inflateGetHeader OF((z_streamp strm,
1.967 + gz_headerp head));
1.968 +/*
1.969 + inflateGetHeader() requests that gzip header information be stored in the
1.970 + provided gz_header structure. inflateGetHeader() may be called after
1.971 + inflateInit2() or inflateReset(), and before the first call of inflate().
1.972 + As inflate() processes the gzip stream, head->done is zero until the header
1.973 + is completed, at which time head->done is set to one. If a zlib stream is
1.974 + being decoded, then head->done is set to -1 to indicate that there will be
1.975 + no gzip header information forthcoming. Note that Z_BLOCK or Z_TREES can be
1.976 + used to force inflate() to return immediately after header processing is
1.977 + complete and before any actual data is decompressed.
1.978 +
1.979 + The text, time, xflags, and os fields are filled in with the gzip header
1.980 + contents. hcrc is set to true if there is a header CRC. (The header CRC
1.981 + was valid if done is set to one.) If extra is not Z_NULL, then extra_max
1.982 + contains the maximum number of bytes to write to extra. Once done is true,
1.983 + extra_len contains the actual extra field length, and extra contains the
1.984 + extra field, or that field truncated if extra_max is less than extra_len.
1.985 + If name is not Z_NULL, then up to name_max characters are written there,
1.986 + terminated with a zero unless the length is greater than name_max. If
1.987 + comment is not Z_NULL, then up to comm_max characters are written there,
1.988 + terminated with a zero unless the length is greater than comm_max. When any
1.989 + of extra, name, or comment are not Z_NULL and the respective field is not
1.990 + present in the header, then that field is set to Z_NULL to signal its
1.991 + absence. This allows the use of deflateSetHeader() with the returned
1.992 + structure to duplicate the header. However if those fields are set to
1.993 + allocated memory, then the application will need to save those pointers
1.994 + elsewhere so that they can be eventually freed.
1.995 +
1.996 + If inflateGetHeader is not used, then the header information is simply
1.997 + discarded. The header is always checked for validity, including the header
1.998 + CRC if present. inflateReset() will reset the process to discard the header
1.999 + information. The application would need to call inflateGetHeader() again to
1.1000 + retrieve the header from the next gzip stream.
1.1001 +
1.1002 + inflateGetHeader returns Z_OK if success, or Z_STREAM_ERROR if the source
1.1003 + stream state was inconsistent.
1.1004 +*/
1.1005 +
1.1006 +/*
1.1007 +ZEXTERN int ZEXPORT inflateBackInit OF((z_streamp strm, int windowBits,
1.1008 + unsigned char FAR *window));
1.1009 +
1.1010 + Initialize the internal stream state for decompression using inflateBack()
1.1011 + calls. The fields zalloc, zfree and opaque in strm must be initialized
1.1012 + before the call. If zalloc and zfree are Z_NULL, then the default library-
1.1013 + derived memory allocation routines are used. windowBits is the base two
1.1014 + logarithm of the window size, in the range 8..15. window is a caller
1.1015 + supplied buffer of that size. Except for special applications where it is
1.1016 + assured that deflate was used with small window sizes, windowBits must be 15
1.1017 + and a 32K byte window must be supplied to be able to decompress general
1.1018 + deflate streams.
1.1019 +
1.1020 + See inflateBack() for the usage of these routines.
1.1021 +
1.1022 + inflateBackInit will return Z_OK on success, Z_STREAM_ERROR if any of
1.1023 + the parameters are invalid, Z_MEM_ERROR if the internal state could not be
1.1024 + allocated, or Z_VERSION_ERROR if the version of the library does not match
1.1025 + the version of the header file.
1.1026 +*/
1.1027 +
1.1028 +typedef unsigned (*in_func) OF((void FAR *,
1.1029 + z_const unsigned char FAR * FAR *));
1.1030 +typedef int (*out_func) OF((void FAR *, unsigned char FAR *, unsigned));
1.1031 +
1.1032 +ZEXTERN int ZEXPORT inflateBack OF((z_streamp strm,
1.1033 + in_func in, void FAR *in_desc,
1.1034 + out_func out, void FAR *out_desc));
1.1035 +/*
1.1036 + inflateBack() does a raw inflate with a single call using a call-back
1.1037 + interface for input and output. This is potentially more efficient than
1.1038 + inflate() for file i/o applications, in that it avoids copying between the
1.1039 + output and the sliding window by simply making the window itself the output
1.1040 + buffer. inflate() can be faster on modern CPUs when used with large
1.1041 + buffers. inflateBack() trusts the application to not change the output
1.1042 + buffer passed by the output function, at least until inflateBack() returns.
1.1043 +
1.1044 + inflateBackInit() must be called first to allocate the internal state
1.1045 + and to initialize the state with the user-provided window buffer.
1.1046 + inflateBack() may then be used multiple times to inflate a complete, raw
1.1047 + deflate stream with each call. inflateBackEnd() is then called to free the
1.1048 + allocated state.
1.1049 +
1.1050 + A raw deflate stream is one with no zlib or gzip header or trailer.
1.1051 + This routine would normally be used in a utility that reads zip or gzip
1.1052 + files and writes out uncompressed files. The utility would decode the
1.1053 + header and process the trailer on its own, hence this routine expects only
1.1054 + the raw deflate stream to decompress. This is different from the normal
1.1055 + behavior of inflate(), which expects either a zlib or gzip header and
1.1056 + trailer around the deflate stream.
1.1057 +
1.1058 + inflateBack() uses two subroutines supplied by the caller that are then
1.1059 + called by inflateBack() for input and output. inflateBack() calls those
1.1060 + routines until it reads a complete deflate stream and writes out all of the
1.1061 + uncompressed data, or until it encounters an error. The function's
1.1062 + parameters and return types are defined above in the in_func and out_func
1.1063 + typedefs. inflateBack() will call in(in_desc, &buf) which should return the
1.1064 + number of bytes of provided input, and a pointer to that input in buf. If
1.1065 + there is no input available, in() must return zero--buf is ignored in that
1.1066 + case--and inflateBack() will return a buffer error. inflateBack() will call
1.1067 + out(out_desc, buf, len) to write the uncompressed data buf[0..len-1]. out()
1.1068 + should return zero on success, or non-zero on failure. If out() returns
1.1069 + non-zero, inflateBack() will return with an error. Neither in() nor out()
1.1070 + are permitted to change the contents of the window provided to
1.1071 + inflateBackInit(), which is also the buffer that out() uses to write from.
1.1072 + The length written by out() will be at most the window size. Any non-zero
1.1073 + amount of input may be provided by in().
1.1074 +
1.1075 + For convenience, inflateBack() can be provided input on the first call by
1.1076 + setting strm->next_in and strm->avail_in. If that input is exhausted, then
1.1077 + in() will be called. Therefore strm->next_in must be initialized before
1.1078 + calling inflateBack(). If strm->next_in is Z_NULL, then in() will be called
1.1079 + immediately for input. If strm->next_in is not Z_NULL, then strm->avail_in
1.1080 + must also be initialized, and then if strm->avail_in is not zero, input will
1.1081 + initially be taken from strm->next_in[0 .. strm->avail_in - 1].
1.1082 +
1.1083 + The in_desc and out_desc parameters of inflateBack() is passed as the
1.1084 + first parameter of in() and out() respectively when they are called. These
1.1085 + descriptors can be optionally used to pass any information that the caller-
1.1086 + supplied in() and out() functions need to do their job.
1.1087 +
1.1088 + On return, inflateBack() will set strm->next_in and strm->avail_in to
1.1089 + pass back any unused input that was provided by the last in() call. The
1.1090 + return values of inflateBack() can be Z_STREAM_END on success, Z_BUF_ERROR
1.1091 + if in() or out() returned an error, Z_DATA_ERROR if there was a format error
1.1092 + in the deflate stream (in which case strm->msg is set to indicate the nature
1.1093 + of the error), or Z_STREAM_ERROR if the stream was not properly initialized.
1.1094 + In the case of Z_BUF_ERROR, an input or output error can be distinguished
1.1095 + using strm->next_in which will be Z_NULL only if in() returned an error. If
1.1096 + strm->next_in is not Z_NULL, then the Z_BUF_ERROR was due to out() returning
1.1097 + non-zero. (in() will always be called before out(), so strm->next_in is
1.1098 + assured to be defined if out() returns non-zero.) Note that inflateBack()
1.1099 + cannot return Z_OK.
1.1100 +*/
1.1101 +
1.1102 +ZEXTERN int ZEXPORT inflateBackEnd OF((z_streamp strm));
1.1103 +/*
1.1104 + All memory allocated by inflateBackInit() is freed.
1.1105 +
1.1106 + inflateBackEnd() returns Z_OK on success, or Z_STREAM_ERROR if the stream
1.1107 + state was inconsistent.
1.1108 +*/
1.1109 +
1.1110 +ZEXTERN uLong ZEXPORT zlibCompileFlags OF((void));
1.1111 +/* Return flags indicating compile-time options.
1.1112 +
1.1113 + Type sizes, two bits each, 00 = 16 bits, 01 = 32, 10 = 64, 11 = other:
1.1114 + 1.0: size of uInt
1.1115 + 3.2: size of uLong
1.1116 + 5.4: size of voidpf (pointer)
1.1117 + 7.6: size of z_off_t
1.1118 +
1.1119 + Compiler, assembler, and debug options:
1.1120 + 8: DEBUG
1.1121 + 9: ASMV or ASMINF -- use ASM code
1.1122 + 10: ZLIB_WINAPI -- exported functions use the WINAPI calling convention
1.1123 + 11: 0 (reserved)
1.1124 +
1.1125 + One-time table building (smaller code, but not thread-safe if true):
1.1126 + 12: BUILDFIXED -- build static block decoding tables when needed
1.1127 + 13: DYNAMIC_CRC_TABLE -- build CRC calculation tables when needed
1.1128 + 14,15: 0 (reserved)
1.1129 +
1.1130 + Library content (indicates missing functionality):
1.1131 + 16: NO_GZCOMPRESS -- gz* functions cannot compress (to avoid linking
1.1132 + deflate code when not needed)
1.1133 + 17: NO_GZIP -- deflate can't write gzip streams, and inflate can't detect
1.1134 + and decode gzip streams (to avoid linking crc code)
1.1135 + 18-19: 0 (reserved)
1.1136 +
1.1137 + Operation variations (changes in library functionality):
1.1138 + 20: PKZIP_BUG_WORKAROUND -- slightly more permissive inflate
1.1139 + 21: FASTEST -- deflate algorithm with only one, lowest compression level
1.1140 + 22,23: 0 (reserved)
1.1141 +
1.1142 + The sprintf variant used by gzprintf (zero is best):
1.1143 + 24: 0 = vs*, 1 = s* -- 1 means limited to 20 arguments after the format
1.1144 + 25: 0 = *nprintf, 1 = *printf -- 1 means gzprintf() not secure!
1.1145 + 26: 0 = returns value, 1 = void -- 1 means inferred string length returned
1.1146 +
1.1147 + Remainder:
1.1148 + 27-31: 0 (reserved)
1.1149 + */
1.1150 +
1.1151 +#ifndef Z_SOLO
1.1152 +
1.1153 + /* utility functions */
1.1154 +
1.1155 +/*
1.1156 + The following utility functions are implemented on top of the basic
1.1157 + stream-oriented functions. To simplify the interface, some default options
1.1158 + are assumed (compression level and memory usage, standard memory allocation
1.1159 + functions). The source code of these utility functions can be modified if
1.1160 + you need special options.
1.1161 +*/
1.1162 +
1.1163 +ZEXTERN int ZEXPORT compress OF((Bytef *dest, uLongf *destLen,
1.1164 + const Bytef *source, uLong sourceLen));
1.1165 +/*
1.1166 + Compresses the source buffer into the destination buffer. sourceLen is
1.1167 + the byte length of the source buffer. Upon entry, destLen is the total size
1.1168 + of the destination buffer, which must be at least the value returned by
1.1169 + compressBound(sourceLen). Upon exit, destLen is the actual size of the
1.1170 + compressed buffer.
1.1171 +
1.1172 + compress returns Z_OK if success, Z_MEM_ERROR if there was not
1.1173 + enough memory, Z_BUF_ERROR if there was not enough room in the output
1.1174 + buffer.
1.1175 +*/
1.1176 +
1.1177 +ZEXTERN int ZEXPORT compress2 OF((Bytef *dest, uLongf *destLen,
1.1178 + const Bytef *source, uLong sourceLen,
1.1179 + int level));
1.1180 +/*
1.1181 + Compresses the source buffer into the destination buffer. The level
1.1182 + parameter has the same meaning as in deflateInit. sourceLen is the byte
1.1183 + length of the source buffer. Upon entry, destLen is the total size of the
1.1184 + destination buffer, which must be at least the value returned by
1.1185 + compressBound(sourceLen). Upon exit, destLen is the actual size of the
1.1186 + compressed buffer.
1.1187 +
1.1188 + compress2 returns Z_OK if success, Z_MEM_ERROR if there was not enough
1.1189 + memory, Z_BUF_ERROR if there was not enough room in the output buffer,
1.1190 + Z_STREAM_ERROR if the level parameter is invalid.
1.1191 +*/
1.1192 +
1.1193 +ZEXTERN uLong ZEXPORT compressBound OF((uLong sourceLen));
1.1194 +/*
1.1195 + compressBound() returns an upper bound on the compressed size after
1.1196 + compress() or compress2() on sourceLen bytes. It would be used before a
1.1197 + compress() or compress2() call to allocate the destination buffer.
1.1198 +*/
1.1199 +
1.1200 +ZEXTERN int ZEXPORT uncompress OF((Bytef *dest, uLongf *destLen,
1.1201 + const Bytef *source, uLong sourceLen));
1.1202 +/*
1.1203 + Decompresses the source buffer into the destination buffer. sourceLen is
1.1204 + the byte length of the source buffer. Upon entry, destLen is the total size
1.1205 + of the destination buffer, which must be large enough to hold the entire
1.1206 + uncompressed data. (The size of the uncompressed data must have been saved
1.1207 + previously by the compressor and transmitted to the decompressor by some
1.1208 + mechanism outside the scope of this compression library.) Upon exit, destLen
1.1209 + is the actual size of the uncompressed buffer.
1.1210 +
1.1211 + uncompress returns Z_OK if success, Z_MEM_ERROR if there was not
1.1212 + enough memory, Z_BUF_ERROR if there was not enough room in the output
1.1213 + buffer, or Z_DATA_ERROR if the input data was corrupted or incomplete. In
1.1214 + the case where there is not enough room, uncompress() will fill the output
1.1215 + buffer with the uncompressed data up to that point.
1.1216 +*/
1.1217 +
1.1218 + /* gzip file access functions */
1.1219 +
1.1220 +/*
1.1221 + This library supports reading and writing files in gzip (.gz) format with
1.1222 + an interface similar to that of stdio, using the functions that start with
1.1223 + "gz". The gzip format is different from the zlib format. gzip is a gzip
1.1224 + wrapper, documented in RFC 1952, wrapped around a deflate stream.
1.1225 +*/
1.1226 +
1.1227 +typedef struct gzFile_s *gzFile; /* semi-opaque gzip file descriptor */
1.1228 +
1.1229 +/*
1.1230 +ZEXTERN gzFile ZEXPORT gzopen OF((const char *path, const char *mode));
1.1231 +
1.1232 + Opens a gzip (.gz) file for reading or writing. The mode parameter is as
1.1233 + in fopen ("rb" or "wb") but can also include a compression level ("wb9") or
1.1234 + a strategy: 'f' for filtered data as in "wb6f", 'h' for Huffman-only
1.1235 + compression as in "wb1h", 'R' for run-length encoding as in "wb1R", or 'F'
1.1236 + for fixed code compression as in "wb9F". (See the description of
1.1237 + deflateInit2 for more information about the strategy parameter.) 'T' will
1.1238 + request transparent writing or appending with no compression and not using
1.1239 + the gzip format.
1.1240 +
1.1241 + "a" can be used instead of "w" to request that the gzip stream that will
1.1242 + be written be appended to the file. "+" will result in an error, since
1.1243 + reading and writing to the same gzip file is not supported. The addition of
1.1244 + "x" when writing will create the file exclusively, which fails if the file
1.1245 + already exists. On systems that support it, the addition of "e" when
1.1246 + reading or writing will set the flag to close the file on an execve() call.
1.1247 +
1.1248 + These functions, as well as gzip, will read and decode a sequence of gzip
1.1249 + streams in a file. The append function of gzopen() can be used to create
1.1250 + such a file. (Also see gzflush() for another way to do this.) When
1.1251 + appending, gzopen does not test whether the file begins with a gzip stream,
1.1252 + nor does it look for the end of the gzip streams to begin appending. gzopen
1.1253 + will simply append a gzip stream to the existing file.
1.1254 +
1.1255 + gzopen can be used to read a file which is not in gzip format; in this
1.1256 + case gzread will directly read from the file without decompression. When
1.1257 + reading, this will be detected automatically by looking for the magic two-
1.1258 + byte gzip header.
1.1259 +
1.1260 + gzopen returns NULL if the file could not be opened, if there was
1.1261 + insufficient memory to allocate the gzFile state, or if an invalid mode was
1.1262 + specified (an 'r', 'w', or 'a' was not provided, or '+' was provided).
1.1263 + errno can be checked to determine if the reason gzopen failed was that the
1.1264 + file could not be opened.
1.1265 +*/
1.1266 +
1.1267 +ZEXTERN gzFile ZEXPORT gzdopen OF((int fd, const char *mode));
1.1268 +/*
1.1269 + gzdopen associates a gzFile with the file descriptor fd. File descriptors
1.1270 + are obtained from calls like open, dup, creat, pipe or fileno (if the file
1.1271 + has been previously opened with fopen). The mode parameter is as in gzopen.
1.1272 +
1.1273 + The next call of gzclose on the returned gzFile will also close the file
1.1274 + descriptor fd, just like fclose(fdopen(fd, mode)) closes the file descriptor
1.1275 + fd. If you want to keep fd open, use fd = dup(fd_keep); gz = gzdopen(fd,
1.1276 + mode);. The duplicated descriptor should be saved to avoid a leak, since
1.1277 + gzdopen does not close fd if it fails. If you are using fileno() to get the
1.1278 + file descriptor from a FILE *, then you will have to use dup() to avoid
1.1279 + double-close()ing the file descriptor. Both gzclose() and fclose() will
1.1280 + close the associated file descriptor, so they need to have different file
1.1281 + descriptors.
1.1282 +
1.1283 + gzdopen returns NULL if there was insufficient memory to allocate the
1.1284 + gzFile state, if an invalid mode was specified (an 'r', 'w', or 'a' was not
1.1285 + provided, or '+' was provided), or if fd is -1. The file descriptor is not
1.1286 + used until the next gz* read, write, seek, or close operation, so gzdopen
1.1287 + will not detect if fd is invalid (unless fd is -1).
1.1288 +*/
1.1289 +
1.1290 +ZEXTERN int ZEXPORT gzbuffer OF((gzFile file, unsigned size));
1.1291 +/*
1.1292 + Set the internal buffer size used by this library's functions. The
1.1293 + default buffer size is 8192 bytes. This function must be called after
1.1294 + gzopen() or gzdopen(), and before any other calls that read or write the
1.1295 + file. The buffer memory allocation is always deferred to the first read or
1.1296 + write. Two buffers are allocated, either both of the specified size when
1.1297 + writing, or one of the specified size and the other twice that size when
1.1298 + reading. A larger buffer size of, for example, 64K or 128K bytes will
1.1299 + noticeably increase the speed of decompression (reading).
1.1300 +
1.1301 + The new buffer size also affects the maximum length for gzprintf().
1.1302 +
1.1303 + gzbuffer() returns 0 on success, or -1 on failure, such as being called
1.1304 + too late.
1.1305 +*/
1.1306 +
1.1307 +ZEXTERN int ZEXPORT gzsetparams OF((gzFile file, int level, int strategy));
1.1308 +/*
1.1309 + Dynamically update the compression level or strategy. See the description
1.1310 + of deflateInit2 for the meaning of these parameters.
1.1311 +
1.1312 + gzsetparams returns Z_OK if success, or Z_STREAM_ERROR if the file was not
1.1313 + opened for writing.
1.1314 +*/
1.1315 +
1.1316 +ZEXTERN int ZEXPORT gzread OF((gzFile file, voidp buf, unsigned len));
1.1317 +/*
1.1318 + Reads the given number of uncompressed bytes from the compressed file. If
1.1319 + the input file is not in gzip format, gzread copies the given number of
1.1320 + bytes into the buffer directly from the file.
1.1321 +
1.1322 + After reaching the end of a gzip stream in the input, gzread will continue
1.1323 + to read, looking for another gzip stream. Any number of gzip streams may be
1.1324 + concatenated in the input file, and will all be decompressed by gzread().
1.1325 + If something other than a gzip stream is encountered after a gzip stream,
1.1326 + that remaining trailing garbage is ignored (and no error is returned).
1.1327 +
1.1328 + gzread can be used to read a gzip file that is being concurrently written.
1.1329 + Upon reaching the end of the input, gzread will return with the available
1.1330 + data. If the error code returned by gzerror is Z_OK or Z_BUF_ERROR, then
1.1331 + gzclearerr can be used to clear the end of file indicator in order to permit
1.1332 + gzread to be tried again. Z_OK indicates that a gzip stream was completed
1.1333 + on the last gzread. Z_BUF_ERROR indicates that the input file ended in the
1.1334 + middle of a gzip stream. Note that gzread does not return -1 in the event
1.1335 + of an incomplete gzip stream. This error is deferred until gzclose(), which
1.1336 + will return Z_BUF_ERROR if the last gzread ended in the middle of a gzip
1.1337 + stream. Alternatively, gzerror can be used before gzclose to detect this
1.1338 + case.
1.1339 +
1.1340 + gzread returns the number of uncompressed bytes actually read, less than
1.1341 + len for end of file, or -1 for error.
1.1342 +*/
1.1343 +
1.1344 +ZEXTERN int ZEXPORT gzwrite OF((gzFile file,
1.1345 + voidpc buf, unsigned len));
1.1346 +/*
1.1347 + Writes the given number of uncompressed bytes into the compressed file.
1.1348 + gzwrite returns the number of uncompressed bytes written or 0 in case of
1.1349 + error.
1.1350 +*/
1.1351 +
1.1352 +ZEXTERN int ZEXPORTVA gzprintf Z_ARG((gzFile file, const char *format, ...));
1.1353 +/*
1.1354 + Converts, formats, and writes the arguments to the compressed file under
1.1355 + control of the format string, as in fprintf. gzprintf returns the number of
1.1356 + uncompressed bytes actually written, or 0 in case of error. The number of
1.1357 + uncompressed bytes written is limited to 8191, or one less than the buffer
1.1358 + size given to gzbuffer(). The caller should assure that this limit is not
1.1359 + exceeded. If it is exceeded, then gzprintf() will return an error (0) with
1.1360 + nothing written. In this case, there may also be a buffer overflow with
1.1361 + unpredictable consequences, which is possible only if zlib was compiled with
1.1362 + the insecure functions sprintf() or vsprintf() because the secure snprintf()
1.1363 + or vsnprintf() functions were not available. This can be determined using
1.1364 + zlibCompileFlags().
1.1365 +*/
1.1366 +
1.1367 +ZEXTERN int ZEXPORT gzputs OF((gzFile file, const char *s));
1.1368 +/*
1.1369 + Writes the given null-terminated string to the compressed file, excluding
1.1370 + the terminating null character.
1.1371 +
1.1372 + gzputs returns the number of characters written, or -1 in case of error.
1.1373 +*/
1.1374 +
1.1375 +ZEXTERN char * ZEXPORT gzgets OF((gzFile file, char *buf, int len));
1.1376 +/*
1.1377 + Reads bytes from the compressed file until len-1 characters are read, or a
1.1378 + newline character is read and transferred to buf, or an end-of-file
1.1379 + condition is encountered. If any characters are read or if len == 1, the
1.1380 + string is terminated with a null character. If no characters are read due
1.1381 + to an end-of-file or len < 1, then the buffer is left untouched.
1.1382 +
1.1383 + gzgets returns buf which is a null-terminated string, or it returns NULL
1.1384 + for end-of-file or in case of error. If there was an error, the contents at
1.1385 + buf are indeterminate.
1.1386 +*/
1.1387 +
1.1388 +ZEXTERN int ZEXPORT gzputc OF((gzFile file, int c));
1.1389 +/*
1.1390 + Writes c, converted to an unsigned char, into the compressed file. gzputc
1.1391 + returns the value that was written, or -1 in case of error.
1.1392 +*/
1.1393 +
1.1394 +ZEXTERN int ZEXPORT gzgetc OF((gzFile file));
1.1395 +/*
1.1396 + Reads one byte from the compressed file. gzgetc returns this byte or -1
1.1397 + in case of end of file or error. This is implemented as a macro for speed.
1.1398 + As such, it does not do all of the checking the other functions do. I.e.
1.1399 + it does not check to see if file is NULL, nor whether the structure file
1.1400 + points to has been clobbered or not.
1.1401 +*/
1.1402 +
1.1403 +ZEXTERN int ZEXPORT gzungetc OF((int c, gzFile file));
1.1404 +/*
1.1405 + Push one character back onto the stream to be read as the first character
1.1406 + on the next read. At least one character of push-back is allowed.
1.1407 + gzungetc() returns the character pushed, or -1 on failure. gzungetc() will
1.1408 + fail if c is -1, and may fail if a character has been pushed but not read
1.1409 + yet. If gzungetc is used immediately after gzopen or gzdopen, at least the
1.1410 + output buffer size of pushed characters is allowed. (See gzbuffer above.)
1.1411 + The pushed character will be discarded if the stream is repositioned with
1.1412 + gzseek() or gzrewind().
1.1413 +*/
1.1414 +
1.1415 +ZEXTERN int ZEXPORT gzflush OF((gzFile file, int flush));
1.1416 +/*
1.1417 + Flushes all pending output into the compressed file. The parameter flush
1.1418 + is as in the deflate() function. The return value is the zlib error number
1.1419 + (see function gzerror below). gzflush is only permitted when writing.
1.1420 +
1.1421 + If the flush parameter is Z_FINISH, the remaining data is written and the
1.1422 + gzip stream is completed in the output. If gzwrite() is called again, a new
1.1423 + gzip stream will be started in the output. gzread() is able to read such
1.1424 + concatented gzip streams.
1.1425 +
1.1426 + gzflush should be called only when strictly necessary because it will
1.1427 + degrade compression if called too often.
1.1428 +*/
1.1429 +
1.1430 +/*
1.1431 +ZEXTERN z_off_t ZEXPORT gzseek OF((gzFile file,
1.1432 + z_off_t offset, int whence));
1.1433 +
1.1434 + Sets the starting position for the next gzread or gzwrite on the given
1.1435 + compressed file. The offset represents a number of bytes in the
1.1436 + uncompressed data stream. The whence parameter is defined as in lseek(2);
1.1437 + the value SEEK_END is not supported.
1.1438 +
1.1439 + If the file is opened for reading, this function is emulated but can be
1.1440 + extremely slow. If the file is opened for writing, only forward seeks are
1.1441 + supported; gzseek then compresses a sequence of zeroes up to the new
1.1442 + starting position.
1.1443 +
1.1444 + gzseek returns the resulting offset location as measured in bytes from
1.1445 + the beginning of the uncompressed stream, or -1 in case of error, in
1.1446 + particular if the file is opened for writing and the new starting position
1.1447 + would be before the current position.
1.1448 +*/
1.1449 +
1.1450 +ZEXTERN int ZEXPORT gzrewind OF((gzFile file));
1.1451 +/*
1.1452 + Rewinds the given file. This function is supported only for reading.
1.1453 +
1.1454 + gzrewind(file) is equivalent to (int)gzseek(file, 0L, SEEK_SET)
1.1455 +*/
1.1456 +
1.1457 +/*
1.1458 +ZEXTERN z_off_t ZEXPORT gztell OF((gzFile file));
1.1459 +
1.1460 + Returns the starting position for the next gzread or gzwrite on the given
1.1461 + compressed file. This position represents a number of bytes in the
1.1462 + uncompressed data stream, and is zero when starting, even if appending or
1.1463 + reading a gzip stream from the middle of a file using gzdopen().
1.1464 +
1.1465 + gztell(file) is equivalent to gzseek(file, 0L, SEEK_CUR)
1.1466 +*/
1.1467 +
1.1468 +/*
1.1469 +ZEXTERN z_off_t ZEXPORT gzoffset OF((gzFile file));
1.1470 +
1.1471 + Returns the current offset in the file being read or written. This offset
1.1472 + includes the count of bytes that precede the gzip stream, for example when
1.1473 + appending or when using gzdopen() for reading. When reading, the offset
1.1474 + does not include as yet unused buffered input. This information can be used
1.1475 + for a progress indicator. On error, gzoffset() returns -1.
1.1476 +*/
1.1477 +
1.1478 +ZEXTERN int ZEXPORT gzeof OF((gzFile file));
1.1479 +/*
1.1480 + Returns true (1) if the end-of-file indicator has been set while reading,
1.1481 + false (0) otherwise. Note that the end-of-file indicator is set only if the
1.1482 + read tried to go past the end of the input, but came up short. Therefore,
1.1483 + just like feof(), gzeof() may return false even if there is no more data to
1.1484 + read, in the event that the last read request was for the exact number of
1.1485 + bytes remaining in the input file. This will happen if the input file size
1.1486 + is an exact multiple of the buffer size.
1.1487 +
1.1488 + If gzeof() returns true, then the read functions will return no more data,
1.1489 + unless the end-of-file indicator is reset by gzclearerr() and the input file
1.1490 + has grown since the previous end of file was detected.
1.1491 +*/
1.1492 +
1.1493 +ZEXTERN int ZEXPORT gzdirect OF((gzFile file));
1.1494 +/*
1.1495 + Returns true (1) if file is being copied directly while reading, or false
1.1496 + (0) if file is a gzip stream being decompressed.
1.1497 +
1.1498 + If the input file is empty, gzdirect() will return true, since the input
1.1499 + does not contain a gzip stream.
1.1500 +
1.1501 + If gzdirect() is used immediately after gzopen() or gzdopen() it will
1.1502 + cause buffers to be allocated to allow reading the file to determine if it
1.1503 + is a gzip file. Therefore if gzbuffer() is used, it should be called before
1.1504 + gzdirect().
1.1505 +
1.1506 + When writing, gzdirect() returns true (1) if transparent writing was
1.1507 + requested ("wT" for the gzopen() mode), or false (0) otherwise. (Note:
1.1508 + gzdirect() is not needed when writing. Transparent writing must be
1.1509 + explicitly requested, so the application already knows the answer. When
1.1510 + linking statically, using gzdirect() will include all of the zlib code for
1.1511 + gzip file reading and decompression, which may not be desired.)
1.1512 +*/
1.1513 +
1.1514 +ZEXTERN int ZEXPORT gzclose OF((gzFile file));
1.1515 +/*
1.1516 + Flushes all pending output if necessary, closes the compressed file and
1.1517 + deallocates the (de)compression state. Note that once file is closed, you
1.1518 + cannot call gzerror with file, since its structures have been deallocated.
1.1519 + gzclose must not be called more than once on the same file, just as free
1.1520 + must not be called more than once on the same allocation.
1.1521 +
1.1522 + gzclose will return Z_STREAM_ERROR if file is not valid, Z_ERRNO on a
1.1523 + file operation error, Z_MEM_ERROR if out of memory, Z_BUF_ERROR if the
1.1524 + last read ended in the middle of a gzip stream, or Z_OK on success.
1.1525 +*/
1.1526 +
1.1527 +ZEXTERN int ZEXPORT gzclose_r OF((gzFile file));
1.1528 +ZEXTERN int ZEXPORT gzclose_w OF((gzFile file));
1.1529 +/*
1.1530 + Same as gzclose(), but gzclose_r() is only for use when reading, and
1.1531 + gzclose_w() is only for use when writing or appending. The advantage to
1.1532 + using these instead of gzclose() is that they avoid linking in zlib
1.1533 + compression or decompression code that is not used when only reading or only
1.1534 + writing respectively. If gzclose() is used, then both compression and
1.1535 + decompression code will be included the application when linking to a static
1.1536 + zlib library.
1.1537 +*/
1.1538 +
1.1539 +ZEXTERN const char * ZEXPORT gzerror OF((gzFile file, int *errnum));
1.1540 +/*
1.1541 + Returns the error message for the last error which occurred on the given
1.1542 + compressed file. errnum is set to zlib error number. If an error occurred
1.1543 + in the file system and not in the compression library, errnum is set to
1.1544 + Z_ERRNO and the application may consult errno to get the exact error code.
1.1545 +
1.1546 + The application must not modify the returned string. Future calls to
1.1547 + this function may invalidate the previously returned string. If file is
1.1548 + closed, then the string previously returned by gzerror will no longer be
1.1549 + available.
1.1550 +
1.1551 + gzerror() should be used to distinguish errors from end-of-file for those
1.1552 + functions above that do not distinguish those cases in their return values.
1.1553 +*/
1.1554 +
1.1555 +ZEXTERN void ZEXPORT gzclearerr OF((gzFile file));
1.1556 +/*
1.1557 + Clears the error and end-of-file flags for file. This is analogous to the
1.1558 + clearerr() function in stdio. This is useful for continuing to read a gzip
1.1559 + file that is being written concurrently.
1.1560 +*/
1.1561 +
1.1562 +#endif /* !Z_SOLO */
1.1563 +
1.1564 + /* checksum functions */
1.1565 +
1.1566 +/*
1.1567 + These functions are not related to compression but are exported
1.1568 + anyway because they might be useful in applications using the compression
1.1569 + library.
1.1570 +*/
1.1571 +
1.1572 +ZEXTERN uLong ZEXPORT adler32 OF((uLong adler, const Bytef *buf, uInt len));
1.1573 +/*
1.1574 + Update a running Adler-32 checksum with the bytes buf[0..len-1] and
1.1575 + return the updated checksum. If buf is Z_NULL, this function returns the
1.1576 + required initial value for the checksum.
1.1577 +
1.1578 + An Adler-32 checksum is almost as reliable as a CRC32 but can be computed
1.1579 + much faster.
1.1580 +
1.1581 + Usage example:
1.1582 +
1.1583 + uLong adler = adler32(0L, Z_NULL, 0);
1.1584 +
1.1585 + while (read_buffer(buffer, length) != EOF) {
1.1586 + adler = adler32(adler, buffer, length);
1.1587 + }
1.1588 + if (adler != original_adler) error();
1.1589 +*/
1.1590 +
1.1591 +/*
1.1592 +ZEXTERN uLong ZEXPORT adler32_combine OF((uLong adler1, uLong adler2,
1.1593 + z_off_t len2));
1.1594 +
1.1595 + Combine two Adler-32 checksums into one. For two sequences of bytes, seq1
1.1596 + and seq2 with lengths len1 and len2, Adler-32 checksums were calculated for
1.1597 + each, adler1 and adler2. adler32_combine() returns the Adler-32 checksum of
1.1598 + seq1 and seq2 concatenated, requiring only adler1, adler2, and len2. Note
1.1599 + that the z_off_t type (like off_t) is a signed integer. If len2 is
1.1600 + negative, the result has no meaning or utility.
1.1601 +*/
1.1602 +
1.1603 +ZEXTERN uLong ZEXPORT crc32 OF((uLong crc, const Bytef *buf, uInt len));
1.1604 +/*
1.1605 + Update a running CRC-32 with the bytes buf[0..len-1] and return the
1.1606 + updated CRC-32. If buf is Z_NULL, this function returns the required
1.1607 + initial value for the crc. Pre- and post-conditioning (one's complement) is
1.1608 + performed within this function so it shouldn't be done by the application.
1.1609 +
1.1610 + Usage example:
1.1611 +
1.1612 + uLong crc = crc32(0L, Z_NULL, 0);
1.1613 +
1.1614 + while (read_buffer(buffer, length) != EOF) {
1.1615 + crc = crc32(crc, buffer, length);
1.1616 + }
1.1617 + if (crc != original_crc) error();
1.1618 +*/
1.1619 +
1.1620 +/*
1.1621 +ZEXTERN uLong ZEXPORT crc32_combine OF((uLong crc1, uLong crc2, z_off_t len2));
1.1622 +
1.1623 + Combine two CRC-32 check values into one. For two sequences of bytes,
1.1624 + seq1 and seq2 with lengths len1 and len2, CRC-32 check values were
1.1625 + calculated for each, crc1 and crc2. crc32_combine() returns the CRC-32
1.1626 + check value of seq1 and seq2 concatenated, requiring only crc1, crc2, and
1.1627 + len2.
1.1628 +*/
1.1629 +
1.1630 +
1.1631 + /* various hacks, don't look :) */
1.1632 +
1.1633 +/* deflateInit and inflateInit are macros to allow checking the zlib version
1.1634 + * and the compiler's view of z_stream:
1.1635 + */
1.1636 +ZEXTERN int ZEXPORT deflateInit_ OF((z_streamp strm, int level,
1.1637 + const char *version, int stream_size));
1.1638 +ZEXTERN int ZEXPORT inflateInit_ OF((z_streamp strm,
1.1639 + const char *version, int stream_size));
1.1640 +ZEXTERN int ZEXPORT deflateInit2_ OF((z_streamp strm, int level, int method,
1.1641 + int windowBits, int memLevel,
1.1642 + int strategy, const char *version,
1.1643 + int stream_size));
1.1644 +ZEXTERN int ZEXPORT inflateInit2_ OF((z_streamp strm, int windowBits,
1.1645 + const char *version, int stream_size));
1.1646 +ZEXTERN int ZEXPORT inflateBackInit_ OF((z_streamp strm, int windowBits,
1.1647 + unsigned char FAR *window,
1.1648 + const char *version,
1.1649 + int stream_size));
1.1650 +#define deflateInit(strm, level) \
1.1651 + deflateInit_((strm), (level), ZLIB_VERSION, (int)sizeof(z_stream))
1.1652 +#define inflateInit(strm) \
1.1653 + inflateInit_((strm), ZLIB_VERSION, (int)sizeof(z_stream))
1.1654 +#define deflateInit2(strm, level, method, windowBits, memLevel, strategy) \
1.1655 + deflateInit2_((strm),(level),(method),(windowBits),(memLevel),\
1.1656 + (strategy), ZLIB_VERSION, (int)sizeof(z_stream))
1.1657 +#define inflateInit2(strm, windowBits) \
1.1658 + inflateInit2_((strm), (windowBits), ZLIB_VERSION, \
1.1659 + (int)sizeof(z_stream))
1.1660 +#define inflateBackInit(strm, windowBits, window) \
1.1661 + inflateBackInit_((strm), (windowBits), (window), \
1.1662 + ZLIB_VERSION, (int)sizeof(z_stream))
1.1663 +
1.1664 +#ifndef Z_SOLO
1.1665 +
1.1666 +/* gzgetc() macro and its supporting function and exposed data structure. Note
1.1667 + * that the real internal state is much larger than the exposed structure.
1.1668 + * This abbreviated structure exposes just enough for the gzgetc() macro. The
1.1669 + * user should not mess with these exposed elements, since their names or
1.1670 + * behavior could change in the future, perhaps even capriciously. They can
1.1671 + * only be used by the gzgetc() macro. You have been warned.
1.1672 + */
1.1673 +struct gzFile_s {
1.1674 + unsigned have;
1.1675 + unsigned char *next;
1.1676 + z_off64_t pos;
1.1677 +};
1.1678 +ZEXTERN int ZEXPORT gzgetc_ OF((gzFile file)); /* backward compatibility */
1.1679 +#ifdef Z_PREFIX_SET
1.1680 +# undef z_gzgetc
1.1681 +# define z_gzgetc(g) \
1.1682 + ((g)->have ? ((g)->have--, (g)->pos++, *((g)->next)++) : gzgetc(g))
1.1683 +#else
1.1684 +# undef gzgetc
1.1685 +# define gzgetc(g) \
1.1686 + ((g)->have ? ((g)->have--, (g)->pos++, *((g)->next)++) : gzgetc(g))
1.1687 +#endif
1.1688 +
1.1689 +/* provide 64-bit offset functions if _LARGEFILE64_SOURCE defined, and/or
1.1690 + * change the regular functions to 64 bits if _FILE_OFFSET_BITS is 64 (if
1.1691 + * both are true, the application gets the *64 functions, and the regular
1.1692 + * functions are changed to 64 bits) -- in case these are set on systems
1.1693 + * without large file support, _LFS64_LARGEFILE must also be true
1.1694 + */
1.1695 +#ifdef Z_LARGE64
1.1696 + ZEXTERN gzFile ZEXPORT gzopen64 OF((const char *, const char *));
1.1697 + ZEXTERN z_off64_t ZEXPORT gzseek64 OF((gzFile, z_off64_t, int));
1.1698 + ZEXTERN z_off64_t ZEXPORT gztell64 OF((gzFile));
1.1699 + ZEXTERN z_off64_t ZEXPORT gzoffset64 OF((gzFile));
1.1700 + ZEXTERN uLong ZEXPORT adler32_combine64 OF((uLong, uLong, z_off64_t));
1.1701 + ZEXTERN uLong ZEXPORT crc32_combine64 OF((uLong, uLong, z_off64_t));
1.1702 +#endif
1.1703 +
1.1704 +#if !defined(ZLIB_INTERNAL) && defined(Z_WANT64)
1.1705 +# ifdef Z_PREFIX_SET
1.1706 +# define z_gzopen z_gzopen64
1.1707 +# define z_gzseek z_gzseek64
1.1708 +# define z_gztell z_gztell64
1.1709 +# define z_gzoffset z_gzoffset64
1.1710 +# define z_adler32_combine z_adler32_combine64
1.1711 +# define z_crc32_combine z_crc32_combine64
1.1712 +# else
1.1713 +# define gzopen gzopen64
1.1714 +# define gzseek gzseek64
1.1715 +# define gztell gztell64
1.1716 +# define gzoffset gzoffset64
1.1717 +# define adler32_combine adler32_combine64
1.1718 +# define crc32_combine crc32_combine64
1.1719 +# endif
1.1720 +# ifndef Z_LARGE64
1.1721 + ZEXTERN gzFile ZEXPORT gzopen64 OF((const char *, const char *));
1.1722 + ZEXTERN z_off_t ZEXPORT gzseek64 OF((gzFile, z_off_t, int));
1.1723 + ZEXTERN z_off_t ZEXPORT gztell64 OF((gzFile));
1.1724 + ZEXTERN z_off_t ZEXPORT gzoffset64 OF((gzFile));
1.1725 + ZEXTERN uLong ZEXPORT adler32_combine64 OF((uLong, uLong, z_off_t));
1.1726 + ZEXTERN uLong ZEXPORT crc32_combine64 OF((uLong, uLong, z_off_t));
1.1727 +# endif
1.1728 +#else
1.1729 + ZEXTERN gzFile ZEXPORT gzopen OF((const char *, const char *));
1.1730 + ZEXTERN z_off_t ZEXPORT gzseek OF((gzFile, z_off_t, int));
1.1731 + ZEXTERN z_off_t ZEXPORT gztell OF((gzFile));
1.1732 + ZEXTERN z_off_t ZEXPORT gzoffset OF((gzFile));
1.1733 + ZEXTERN uLong ZEXPORT adler32_combine OF((uLong, uLong, z_off_t));
1.1734 + ZEXTERN uLong ZEXPORT crc32_combine OF((uLong, uLong, z_off_t));
1.1735 +#endif
1.1736 +
1.1737 +#else /* Z_SOLO */
1.1738 +
1.1739 + ZEXTERN uLong ZEXPORT adler32_combine OF((uLong, uLong, z_off_t));
1.1740 + ZEXTERN uLong ZEXPORT crc32_combine OF((uLong, uLong, z_off_t));
1.1741 +
1.1742 +#endif /* !Z_SOLO */
1.1743 +
1.1744 +/* hack for buggy compilers */
1.1745 +#if !defined(ZUTIL_H) && !defined(NO_DUMMY_DECL)
1.1746 + struct internal_state {int dummy;};
1.1747 +#endif
1.1748 +
1.1749 +/* undocumented functions */
1.1750 +ZEXTERN const char * ZEXPORT zError OF((int));
1.1751 +ZEXTERN int ZEXPORT inflateSyncPoint OF((z_streamp));
1.1752 +ZEXTERN const z_crc_t FAR * ZEXPORT get_crc_table OF((void));
1.1753 +ZEXTERN int ZEXPORT inflateUndermine OF((z_streamp, int));
1.1754 +ZEXTERN int ZEXPORT inflateResetKeep OF((z_streamp));
1.1755 +ZEXTERN int ZEXPORT deflateResetKeep OF((z_streamp));
1.1756 +#if defined(_WIN32) && !defined(Z_SOLO)
1.1757 +ZEXTERN gzFile ZEXPORT gzopen_w OF((const wchar_t *path,
1.1758 + const char *mode));
1.1759 +#endif
1.1760 +#if defined(STDC) || defined(Z_HAVE_STDARG_H)
1.1761 +# ifndef Z_SOLO
1.1762 +ZEXTERN int ZEXPORTVA gzvprintf Z_ARG((gzFile file,
1.1763 + const char *format,
1.1764 + va_list va));
1.1765 +# endif
1.1766 +#endif
1.1767 +
1.1768 +#ifdef __cplusplus
1.1769 +}
1.1770 +#endif
1.1771 +
1.1772 +#endif /* ZLIB_H */
