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-/* zlib.h -- interface of the 'zlib' general purpose compression library
- version 1.2.5, April 19th, 2010
-
- Copyright (C) 1995-2010 Jean-loup Gailly and Mark Adler
-
- This software is provided 'as-is', without any express or implied
- warranty. In no event will the authors be held liable for any damages
- arising from the use of this software.
-
- Permission is granted to anyone to use this software for any purpose,
- including commercial applications, and to alter it and redistribute it
- freely, subject to the following restrictions:
-
- 1. The origin of this software must not be misrepresented; you must not
- claim that you wrote the original software. If you use this software
- in a product, an acknowledgment in the product documentation would be
- appreciated but is not required.
- 2. Altered source versions must be plainly marked as such, and must not be
- misrepresented as being the original software.
- 3. This notice may not be removed or altered from any source distribution.
-
- Jean-loup Gailly Mark Adler
- jloup@gzip.org madler@alumni.caltech.edu
-
-
- The data format used by the zlib library is described by RFCs (Request for
- Comments) 1950 to 1952 in the files http://www.ietf.org/rfc/rfc1950.txt
- (zlib format), rfc1951.txt (deflate format) and rfc1952.txt (gzip format).
-*/
-
-#ifndef ZLIB_H
-#define ZLIB_H
-
-#include "zconf.h"
-
-#ifdef __cplusplus
-extern "C" {
-#endif
-
-#define ZLIB_VERSION "1.2.5"
-#define ZLIB_VERNUM 0x1250
-#define ZLIB_VER_MAJOR 1
-#define ZLIB_VER_MINOR 2
-#define ZLIB_VER_REVISION 5
-#define ZLIB_VER_SUBREVISION 0
-
-/*
- The 'zlib' compression library provides in-memory compression and
- decompression functions, including integrity checks of the uncompressed data.
- This version of the library supports only one compression method (deflation)
- but other algorithms will be added later and will have the same stream
- interface.
-
- Compression can be done in a single step if the buffers are large enough,
- or can be done by repeated calls of the compression function. In the latter
- case, the application must provide more input and/or consume the output
- (providing more output space) before each call.
-
- The compressed data format used by default by the in-memory functions is
- the zlib format, which is a zlib wrapper documented in RFC 1950, wrapped
- around a deflate stream, which is itself documented in RFC 1951.
-
- The library also supports reading and writing files in gzip (.gz) format
- with an interface similar to that of stdio using the functions that start
- with "gz". The gzip format is different from the zlib format. gzip is a
- gzip wrapper, documented in RFC 1952, wrapped around a deflate stream.
-
- This library can optionally read and write gzip streams in memory as well.
-
- The zlib format was designed to be compact and fast for use in memory
- and on communications channels. The gzip format was designed for single-
- file compression on file systems, has a larger header than zlib to maintain
- directory information, and uses a different, slower check method than zlib.
-
- The library does not install any signal handler. The decoder checks
- the consistency of the compressed data, so the library should never crash
- even in case of corrupted input.
-*/
-
-typedef voidpf (*alloc_func) OF((voidpf opaque, uInt items, uInt size));
-typedef void (*free_func) OF((voidpf opaque, voidpf address));
-
-struct internal_state;
-
-typedef struct z_stream_s {
- Bytef *next_in; /* next input byte */
- uInt avail_in; /* number of bytes available at next_in */
- uLong total_in; /* total nb of input bytes read so far */
-
- Bytef *next_out; /* next output byte should be put there */
- uInt avail_out; /* remaining free space at next_out */
- uLong total_out; /* total nb of bytes output so far */
-
- char *msg; /* last error message, NULL if no error */
- struct internal_state FAR *state; /* not visible by applications */
-
- alloc_func zalloc; /* used to allocate the internal state */
- free_func zfree; /* used to free the internal state */
- voidpf opaque; /* private data object passed to zalloc and zfree */
-
- int data_type; /* best guess about the data type: binary or text */
- uLong adler; /* adler32 value of the uncompressed data */
- uLong reserved; /* reserved for future use */
-} z_stream;
-
-typedef z_stream FAR *z_streamp;
-
-/*
- gzip header information passed to and from zlib routines. See RFC 1952
- for more details on the meanings of these fields.
-*/
-typedef struct gz_header_s {
- int text; /* true if compressed data believed to be text */
- uLong time; /* modification time */
- int xflags; /* extra flags (not used when writing a gzip file) */
- int os; /* operating system */
- Bytef *extra; /* pointer to extra field or Z_NULL if none */
- uInt extra_len; /* extra field length (valid if extra != Z_NULL) */
- uInt extra_max; /* space at extra (only when reading header) */
- Bytef *name; /* pointer to zero-terminated file name or Z_NULL */
- uInt name_max; /* space at name (only when reading header) */
- Bytef *comment; /* pointer to zero-terminated comment or Z_NULL */
- uInt comm_max; /* space at comment (only when reading header) */
- int hcrc; /* true if there was or will be a header crc */
- int done; /* true when done reading gzip header (not used
- when writing a gzip file) */
-} gz_header;
-
-typedef gz_header FAR *gz_headerp;
-
-/*
- The application must update next_in and avail_in when avail_in has dropped
- to zero. It must update next_out and avail_out when avail_out has dropped
- to zero. The application must initialize zalloc, zfree and opaque before
- calling the init function. All other fields are set by the compression
- library and must not be updated by the application.
-
- The opaque value provided by the application will be passed as the first
- parameter for calls of zalloc and zfree. This can be useful for custom
- memory management. The compression library attaches no meaning to the
- opaque value.
-
- zalloc must return Z_NULL if there is not enough memory for the object.
- If zlib is used in a multi-threaded application, zalloc and zfree must be
- thread safe.
-
- On 16-bit systems, the functions zalloc and zfree must be able to allocate
- exactly 65536 bytes, but will not be required to allocate more than this if
- the symbol MAXSEG_64K is defined (see zconf.h). WARNING: On MSDOS, pointers
- returned by zalloc for objects of exactly 65536 bytes *must* have their
- offset normalized to zero. The default allocation function provided by this
- library ensures this (see zutil.c). To reduce memory requirements and avoid
- any allocation of 64K objects, at the expense of compression ratio, compile
- the library with -DMAX_WBITS=14 (see zconf.h).
-
- The fields total_in and total_out can be used for statistics or progress
- reports. After compression, total_in holds the total size of the
- uncompressed data and may be saved for use in the decompressor (particularly
- if the decompressor wants to decompress everything in a single step).
-*/
-
- /* constants */
-
-#define Z_NO_FLUSH 0
-#define Z_PARTIAL_FLUSH 1
-#define Z_SYNC_FLUSH 2
-#define Z_FULL_FLUSH 3
-#define Z_FINISH 4
-#define Z_BLOCK 5
-#define Z_TREES 6
-/* Allowed flush values; see deflate() and inflate() below for details */
-
-#define Z_OK 0
-#define Z_STREAM_END 1
-#define Z_NEED_DICT 2
-#define Z_ERRNO (-1)
-#define Z_STREAM_ERROR (-2)
-#define Z_DATA_ERROR (-3)
-#define Z_MEM_ERROR (-4)
-#define Z_BUF_ERROR (-5)
-#define Z_VERSION_ERROR (-6)
-/* Return codes for the compression/decompression functions. Negative values
- * are errors, positive values are used for special but normal events.
- */
-
-#define Z_NO_COMPRESSION 0
-#define Z_BEST_SPEED 1
-#define Z_BEST_COMPRESSION 9
-#define Z_DEFAULT_COMPRESSION (-1)
-/* compression levels */
-
-#define Z_FILTERED 1
-#define Z_HUFFMAN_ONLY 2
-#define Z_RLE 3
-#define Z_FIXED 4
-#define Z_DEFAULT_STRATEGY 0
-/* compression strategy; see deflateInit2() below for details */
-
-#define Z_BINARY 0
-#define Z_TEXT 1
-#define Z_ASCII Z_TEXT /* for compatibility with 1.2.2 and earlier */
-#define Z_UNKNOWN 2
-/* Possible values of the data_type field (though see inflate()) */
-
-#define Z_DEFLATED 8
-/* The deflate compression method (the only one supported in this version) */
-
-#define Z_NULL 0 /* for initializing zalloc, zfree, opaque */
-
-#define zlib_version zlibVersion()
-/* for compatibility with versions < 1.0.2 */
-
-
- /* basic functions */
-
-ZEXTERN const char * ZEXPORT zlibVersion OF((void));
-/* The application can compare zlibVersion and ZLIB_VERSION for consistency.
- If the first character differs, the library code actually used is not
- compatible with the zlib.h header file used by the application. This check
- is automatically made by deflateInit and inflateInit.
- */
-
-/*
-ZEXTERN int ZEXPORT deflateInit OF((z_streamp strm, int level));
-
- Initializes the internal stream state for compression. The fields
- zalloc, zfree and opaque must be initialized before by the caller. If
- zalloc and zfree are set to Z_NULL, deflateInit updates them to use default
- allocation functions.
-
- The compression level must be Z_DEFAULT_COMPRESSION, or between 0 and 9:
- 1 gives best speed, 9 gives best compression, 0 gives no compression at all
- (the input data is simply copied a block at a time). Z_DEFAULT_COMPRESSION
- requests a default compromise between speed and compression (currently
- equivalent to level 6).
-
- deflateInit returns Z_OK if success, Z_MEM_ERROR if there was not enough
- memory, Z_STREAM_ERROR if level is not a valid compression level, or
- Z_VERSION_ERROR if the zlib library version (zlib_version) is incompatible
- with the version assumed by the caller (ZLIB_VERSION). msg is set to null
- if there is no error message. deflateInit does not perform any compression:
- this will be done by deflate().
-*/
-
-
-ZEXTERN int ZEXPORT deflate OF((z_streamp strm, int flush));
-/*
- deflate compresses as much data as possible, and stops when the input
- buffer becomes empty or the output buffer becomes full. It may introduce
- some output latency (reading input without producing any output) except when
- forced to flush.
-
- The detailed semantics are as follows. deflate performs one or both of the
- following actions:
-
- - Compress more input starting at next_in and update next_in and avail_in
- accordingly. If not all input can be processed (because there is not
- enough room in the output buffer), next_in and avail_in are updated and
- processing will resume at this point for the next call of deflate().
-
- - Provide more output starting at next_out and update next_out and avail_out
- accordingly. This action is forced if the parameter flush is non zero.
- Forcing flush frequently degrades the compression ratio, so this parameter
- should be set only when necessary (in interactive applications). Some
- output may be provided even if flush is not set.
-
- Before the call of deflate(), the application should ensure that at least
- one of the actions is possible, by providing more input and/or consuming more
- output, and updating avail_in or avail_out accordingly; avail_out should
- never be zero before the call. The application can consume the compressed
- output when it wants, for example when the output buffer is full (avail_out
- == 0), or after each call of deflate(). If deflate returns Z_OK and with
- zero avail_out, it must be called again after making room in the output
- buffer because there might be more output pending.
-
- Normally the parameter flush is set to Z_NO_FLUSH, which allows deflate to
- decide how much data to accumulate before producing output, in order to
- maximize compression.
-
- If the parameter flush is set to Z_SYNC_FLUSH, all pending output is
- flushed to the output buffer and the output is aligned on a byte boundary, so
- that the decompressor can get all input data available so far. (In
- particular avail_in is zero after the call if enough output space has been
- provided before the call.) Flushing may degrade compression for some
- compression algorithms and so it should be used only when necessary. This
- completes the current deflate block and follows it with an empty stored block
- that is three bits plus filler bits to the next byte, followed by four bytes
- (00 00 ff ff).
-
- If flush is set to Z_PARTIAL_FLUSH, all pending output is flushed to the
- output buffer, but the output is not aligned to a byte boundary. All of the
- input data so far will be available to the decompressor, as for Z_SYNC_FLUSH.
- This completes the current deflate block and follows it with an empty fixed
- codes block that is 10 bits long. This assures that enough bytes are output
- in order for the decompressor to finish the block before the empty fixed code
- block.
-
- If flush is set to Z_BLOCK, a deflate block is completed and emitted, as
- for Z_SYNC_FLUSH, but the output is not aligned on a byte boundary, and up to
- seven bits of the current block are held to be written as the next byte after
- the next deflate block is completed. In this case, the decompressor may not
- be provided enough bits at this point in order to complete decompression of
- the data provided so far to the compressor. It may need to wait for the next
- block to be emitted. This is for advanced applications that need to control
- the emission of deflate blocks.
-
- If flush is set to Z_FULL_FLUSH, all output is flushed as with
- Z_SYNC_FLUSH, and the compression state is reset so that decompression can
- restart from this point if previous compressed data has been damaged or if
- random access is desired. Using Z_FULL_FLUSH too often can seriously degrade
- compression.
-
- If deflate returns with avail_out == 0, this function must be called again
- with the same value of the flush parameter and more output space (updated
- avail_out), until the flush is complete (deflate returns with non-zero
- avail_out). In the case of a Z_FULL_FLUSH or Z_SYNC_FLUSH, make sure that
- avail_out is greater than six to avoid repeated flush markers due to
- avail_out == 0 on return.
-
- If the parameter flush is set to Z_FINISH, pending input is processed,
- pending output is flushed and deflate returns with Z_STREAM_END if there was
- enough output space; if deflate returns with Z_OK, this function must be
- called again with Z_FINISH and more output space (updated avail_out) but no
- more input data, until it returns with Z_STREAM_END or an error. After
- deflate has returned Z_STREAM_END, the only possible operations on the stream
- are deflateReset or deflateEnd.
-
- Z_FINISH can be used immediately after deflateInit if all the compression
- is to be done in a single step. In this case, avail_out must be at least the
- value returned by deflateBound (see below). If deflate does not return
- Z_STREAM_END, then it must be called again as described above.
-
- deflate() sets strm->adler to the adler32 checksum of all input read
- so far (that is, total_in bytes).
-
- deflate() may update strm->data_type if it can make a good guess about
- the input data type (Z_BINARY or Z_TEXT). In doubt, the data is considered
- binary. This field is only for information purposes and does not affect the
- compression algorithm in any manner.
-
- deflate() returns Z_OK if some progress has been made (more input
- processed or more output produced), Z_STREAM_END if all input has been
- consumed and all output has been produced (only when flush is set to
- Z_FINISH), Z_STREAM_ERROR if the stream state was inconsistent (for example
- if next_in or next_out was Z_NULL), Z_BUF_ERROR if no progress is possible
- (for example avail_in or avail_out was zero). Note that Z_BUF_ERROR is not
- fatal, and deflate() can be called again with more input and more output
- space to continue compressing.
-*/
-
-
-ZEXTERN int ZEXPORT deflateEnd OF((z_streamp strm));
-/*
- All dynamically allocated data structures for this stream are freed.
- This function discards any unprocessed input and does not flush any pending
- output.
-
- deflateEnd returns Z_OK if success, Z_STREAM_ERROR if the
- stream state was inconsistent, Z_DATA_ERROR if the stream was freed
- prematurely (some input or output was discarded). In the error case, msg
- may be set but then points to a static string (which must not be
- deallocated).
-*/
-
-
-/*
-ZEXTERN int ZEXPORT inflateInit OF((z_streamp strm));
-
- Initializes the internal stream state for decompression. The fields
- next_in, avail_in, zalloc, zfree and opaque must be initialized before by
- the caller. If next_in is not Z_NULL and avail_in is large enough (the
- exact value depends on the compression method), inflateInit determines the
- compression method from the zlib header and allocates all data structures
- accordingly; otherwise the allocation will be deferred to the first call of
- inflate. If zalloc and zfree are set to Z_NULL, inflateInit updates them to
- use default allocation functions.
-
- inflateInit returns Z_OK if success, Z_MEM_ERROR if there was not enough
- memory, Z_VERSION_ERROR if the zlib library version is incompatible with the
- version assumed by the caller, or Z_STREAM_ERROR if the parameters are
- invalid, such as a null pointer to the structure. msg is set to null if
- there is no error message. inflateInit does not perform any decompression
- apart from possibly reading the zlib header if present: actual decompression
- will be done by inflate(). (So next_in and avail_in may be modified, but
- next_out and avail_out are unused and unchanged.) The current implementation
- of inflateInit() does not process any header information -- that is deferred
- until inflate() is called.
-*/
-
-
-ZEXTERN int ZEXPORT inflate OF((z_streamp strm, int flush));
-/*
- inflate decompresses as much data as possible, and stops when the input
- buffer becomes empty or the output buffer becomes full. It may introduce
- some output latency (reading input without producing any output) except when
- forced to flush.
-
- The detailed semantics are as follows. inflate performs one or both of the
- following actions:
-
- - Decompress more input starting at next_in and update next_in and avail_in
- accordingly. If not all input can be processed (because there is not
- enough room in the output buffer), next_in is updated and processing will
- resume at this point for the next call of inflate().
-
- - Provide more output starting at next_out and update next_out and avail_out
- accordingly. inflate() provides as much output as possible, until there is
- no more input data or no more space in the output buffer (see below about
- the flush parameter).
-
- Before the call of inflate(), the application should ensure that at least
- one of the actions is possible, by providing more input and/or consuming more
- output, and updating the next_* and avail_* values accordingly. The
- application can consume the uncompressed output when it wants, for example
- when the output buffer is full (avail_out == 0), or after each call of
- inflate(). If inflate returns Z_OK and with zero avail_out, it must be
- called again after making room in the output buffer because there might be
- more output pending.
-
- The flush parameter of inflate() can be Z_NO_FLUSH, Z_SYNC_FLUSH, Z_FINISH,
- Z_BLOCK, or Z_TREES. Z_SYNC_FLUSH requests that inflate() flush as much
- output as possible to the output buffer. Z_BLOCK requests that inflate()
- stop if and when it gets to the next deflate block boundary. When decoding
- the zlib or gzip format, this will cause inflate() to return immediately
- after the header and before the first block. When doing a raw inflate,
- inflate() will go ahead and process the first block, and will return when it
- gets to the end of that block, or when it runs out of data.
-
- The Z_BLOCK option assists in appending to or combining deflate streams.
- Also to assist in this, on return inflate() will set strm->data_type to the
- number of unused bits in the last byte taken from strm->next_in, plus 64 if
- inflate() is currently decoding the last block in the deflate stream, plus
- 128 if inflate() returned immediately after decoding an end-of-block code or
- decoding the complete header up to just before the first byte of the deflate
- stream. The end-of-block will not be indicated until all of the uncompressed
- data from that block has been written to strm->next_out. The number of
- unused bits may in general be greater than seven, except when bit 7 of
- data_type is set, in which case the number of unused bits will be less than
- eight. data_type is set as noted here every time inflate() returns for all
- flush options, and so can be used to determine the amount of currently
- consumed input in bits.
-
- The Z_TREES option behaves as Z_BLOCK does, but it also returns when the
- end of each deflate block header is reached, before any actual data in that
- block is decoded. This allows the caller to determine the length of the
- deflate block header for later use in random access within a deflate block.
- 256 is added to the value of strm->data_type when inflate() returns
- immediately after reaching the end of the deflate block header.
-
- inflate() should normally be called until it returns Z_STREAM_END or an
- error. However if all decompression is to be performed in a single step (a
- single call of inflate), the parameter flush should be set to Z_FINISH. In
- this case all pending input is processed and all pending output is flushed;
- avail_out must be large enough to hold all the uncompressed data. (The size
- of the uncompressed data may have been saved by the compressor for this
- purpose.) The next operation on this stream must be inflateEnd to deallocate
- the decompression state. The use of Z_FINISH is never required, but can be
- used to inform inflate that a faster approach may be used for the single
- inflate() call.
-
- In this implementation, inflate() always flushes as much output as
- possible to the output buffer, and always uses the faster approach on the
- first call. So the only effect of the flush parameter in this implementation
- is on the return value of inflate(), as noted below, or when it returns early
- because Z_BLOCK or Z_TREES is used.
-
- If a preset dictionary is needed after this call (see inflateSetDictionary
- below), inflate sets strm->adler to the adler32 checksum of the dictionary
- chosen by the compressor and returns Z_NEED_DICT; otherwise it sets
- strm->adler to the adler32 checksum of all output produced so far (that is,
- total_out bytes) and returns Z_OK, Z_STREAM_END or an error code as described
- below. At the end of the stream, inflate() checks that its computed adler32
- checksum is equal to that saved by the compressor and returns Z_STREAM_END
- only if the checksum is correct.
-
- inflate() can decompress and check either zlib-wrapped or gzip-wrapped
- deflate data. The header type is detected automatically, if requested when
- initializing with inflateInit2(). Any information contained in the gzip
- header is not retained, so applications that need that information should
- instead use raw inflate, see inflateInit2() below, or inflateBack() and
- perform their own processing of the gzip header and trailer.
-
- inflate() returns Z_OK if some progress has been made (more input processed
- or more output produced), Z_STREAM_END if the end of the compressed data has
- been reached and all uncompressed output has been produced, Z_NEED_DICT if a
- preset dictionary is needed at this point, Z_DATA_ERROR if the input data was
- corrupted (input stream not conforming to the zlib format or incorrect check
- value), Z_STREAM_ERROR if the stream structure was inconsistent (for example
- next_in or next_out was Z_NULL), Z_MEM_ERROR if there was not enough memory,
- Z_BUF_ERROR if no progress is possible or if there was not enough room in the
- output buffer when Z_FINISH is used. Note that Z_BUF_ERROR is not fatal, and
- inflate() can be called again with more input and more output space to
- continue decompressing. If Z_DATA_ERROR is returned, the application may
- then call inflateSync() to look for a good compression block if a partial
- recovery of the data is desired.
-*/
-
-
-ZEXTERN int ZEXPORT inflateEnd OF((z_streamp strm));
-/*
- All dynamically allocated data structures for this stream are freed.
- This function discards any unprocessed input and does not flush any pending
- output.
-
- inflateEnd returns Z_OK if success, Z_STREAM_ERROR if the stream state
- was inconsistent. In the error case, msg may be set but then points to a
- static string (which must not be deallocated).
-*/
-
-
- /* Advanced functions */
-
-/*
- The following functions are needed only in some special applications.
-*/
-
-/*
-ZEXTERN int ZEXPORT deflateInit2 OF((z_streamp strm,
- int level,
- int method,
- int windowBits,
- int memLevel,
- int strategy));
-
- This is another version of deflateInit with more compression options. The
- fields next_in, zalloc, zfree and opaque must be initialized before by the
- caller.
-
- The method parameter is the compression method. It must be Z_DEFLATED in
- this version of the library.
-
- The windowBits parameter is the base two logarithm of the window size
- (the size of the history buffer). It should be in the range 8..15 for this
- version of the library. Larger values of this parameter result in better
- compression at the expense of memory usage. The default value is 15 if
- deflateInit is used instead.
-
- windowBits can also be -8..-15 for raw deflate. In this case, -windowBits
- determines the window size. deflate() will then generate raw deflate data
- with no zlib header or trailer, and will not compute an adler32 check value.
-
- windowBits can also be greater than 15 for optional gzip encoding. Add
- 16 to windowBits to write a simple gzip header and trailer around the
- compressed data instead of a zlib wrapper. The gzip header will have no
- file name, no extra data, no comment, no modification time (set to zero), no
- header crc, and the operating system will be set to 255 (unknown). If a
- gzip stream is being written, strm->adler is a crc32 instead of an adler32.
-
- The memLevel parameter specifies how much memory should be allocated
- for the internal compression state. memLevel=1 uses minimum memory but is
- slow and reduces compression ratio; memLevel=9 uses maximum memory for
- optimal speed. The default value is 8. See zconf.h for total memory usage
- as a function of windowBits and memLevel.
-
- The strategy parameter is used to tune the compression algorithm. Use the
- value Z_DEFAULT_STRATEGY for normal data, Z_FILTERED for data produced by a
- filter (or predictor), Z_HUFFMAN_ONLY to force Huffman encoding only (no
- string match), or Z_RLE to limit match distances to one (run-length
- encoding). Filtered data consists mostly of small values with a somewhat
- random distribution. In this case, the compression algorithm is tuned to
- compress them better. The effect of Z_FILTERED is to force more Huffman
- coding and less string matching; it is somewhat intermediate between
- Z_DEFAULT_STRATEGY and Z_HUFFMAN_ONLY. Z_RLE is designed to be almost as
- fast as Z_HUFFMAN_ONLY, but give better compression for PNG image data. The
- strategy parameter only affects the compression ratio but not the
- correctness of the compressed output even if it is not set appropriately.
- Z_FIXED prevents the use of dynamic Huffman codes, allowing for a simpler
- decoder for special applications.
-
- deflateInit2 returns Z_OK if success, Z_MEM_ERROR if there was not enough
- memory, Z_STREAM_ERROR if any parameter is invalid (such as an invalid
- method), or Z_VERSION_ERROR if the zlib library version (zlib_version) is
- incompatible with the version assumed by the caller (ZLIB_VERSION). msg is
- set to null if there is no error message. deflateInit2 does not perform any
- compression: this will be done by deflate().
-*/
-
-ZEXTERN int ZEXPORT deflateSetDictionary OF((z_streamp strm,
- const Bytef *dictionary,
- uInt dictLength));
-/*
- Initializes the compression dictionary from the given byte sequence
- without producing any compressed output. This function must be called
- immediately after deflateInit, deflateInit2 or deflateReset, before any call
- of deflate. The compressor and decompressor must use exactly the same
- dictionary (see inflateSetDictionary).
-
- The dictionary should consist of strings (byte sequences) that are likely
- to be encountered later in the data to be compressed, with the most commonly
- used strings preferably put towards the end of the dictionary. Using a
- dictionary is most useful when the data to be compressed is short and can be
- predicted with good accuracy; the data can then be compressed better than
- with the default empty dictionary.
-
- Depending on the size of the compression data structures selected by
- deflateInit or deflateInit2, a part of the dictionary may in effect be
- discarded, for example if the dictionary is larger than the window size
- provided in deflateInit or deflateInit2. Thus the strings most likely to be
- useful should be put at the end of the dictionary, not at the front. In
- addition, the current implementation of deflate will use at most the window
- size minus 262 bytes of the provided dictionary.
-
- Upon return of this function, strm->adler is set to the adler32 value
- of the dictionary; the decompressor may later use this value to determine
- which dictionary has been used by the compressor. (The adler32 value
- applies to the whole dictionary even if only a subset of the dictionary is
- actually used by the compressor.) If a raw deflate was requested, then the
- adler32 value is not computed and strm->adler is not set.
-
- deflateSetDictionary returns Z_OK if success, or Z_STREAM_ERROR if a
- parameter is invalid (e.g. dictionary being Z_NULL) or the stream state is
- inconsistent (for example if deflate has already been called for this stream
- or if the compression method is bsort). deflateSetDictionary does not
- perform any compression: this will be done by deflate().
-*/
-
-ZEXTERN int ZEXPORT deflateCopy OF((z_streamp dest,
- z_streamp source));
-/*
- Sets the destination stream as a complete copy of the source stream.
-
- This function can be useful when several compression strategies will be
- tried, for example when there are several ways of pre-processing the input
- data with a filter. The streams that will be discarded should then be freed
- by calling deflateEnd. Note that deflateCopy duplicates the internal
- compression state which can be quite large, so this strategy is slow and can
- consume lots of memory.
-
- deflateCopy returns Z_OK if success, Z_MEM_ERROR if there was not
- enough memory, Z_STREAM_ERROR if the source stream state was inconsistent
- (such as zalloc being Z_NULL). msg is left unchanged in both source and
- destination.
-*/
-
-ZEXTERN int ZEXPORT deflateReset OF((z_streamp strm));
-/*
- This function is equivalent to deflateEnd followed by deflateInit,
- but does not free and reallocate all the internal compression state. The
- stream will keep the same compression level and any other attributes that
- may have been set by deflateInit2.
-
- deflateReset returns Z_OK if success, or Z_STREAM_ERROR if the source
- stream state was inconsistent (such as zalloc or state being Z_NULL).
-*/
-
-ZEXTERN int ZEXPORT deflateParams OF((z_streamp strm,
- int level,
- int strategy));
-/*
- Dynamically update the compression level and compression strategy. The
- interpretation of level and strategy is as in deflateInit2. This can be
- used to switch between compression and straight copy of the input data, or
- to switch to a different kind of input data requiring a different strategy.
- If the compression level is changed, the input available so far is
- compressed with the old level (and may be flushed); the new level will take
- effect only at the next call of deflate().
-
- Before the call of deflateParams, the stream state must be set as for
- a call of deflate(), since the currently available input may have to be
- compressed and flushed. In particular, strm->avail_out must be non-zero.
-
- deflateParams returns Z_OK if success, Z_STREAM_ERROR if the source
- stream state was inconsistent or if a parameter was invalid, Z_BUF_ERROR if
- strm->avail_out was zero.
-*/
-
-ZEXTERN int ZEXPORT deflateTune OF((z_streamp strm,
- int good_length,
- int max_lazy,
- int nice_length,
- int max_chain));
-/*
- Fine tune deflate's internal compression parameters. This should only be
- used by someone who understands the algorithm used by zlib's deflate for
- searching for the best matching string, and even then only by the most
- fanatic optimizer trying to squeeze out the last compressed bit for their
- specific input data. Read the deflate.c source code for the meaning of the
- max_lazy, good_length, nice_length, and max_chain parameters.
-
- deflateTune() can be called after deflateInit() or deflateInit2(), and
- returns Z_OK on success, or Z_STREAM_ERROR for an invalid deflate stream.
- */
-
-ZEXTERN uLong ZEXPORT deflateBound OF((z_streamp strm,
- uLong sourceLen));
-/*
- deflateBound() returns an upper bound on the compressed size after
- deflation of sourceLen bytes. It must be called after deflateInit() or
- deflateInit2(), and after deflateSetHeader(), if used. This would be used
- to allocate an output buffer for deflation in a single pass, and so would be
- called before deflate().
-*/
-
-ZEXTERN int ZEXPORT deflatePrime OF((z_streamp strm,
- int bits,
- int value));
-/*
- deflatePrime() inserts bits in the deflate output stream. The intent
- is that this function is used to start off the deflate output with the bits
- leftover from a previous deflate stream when appending to it. As such, this
- function can only be used for raw deflate, and must be used before the first
- deflate() call after a deflateInit2() or deflateReset(). bits must be less
- than or equal to 16, and that many of the least significant bits of value
- will be inserted in the output.
-
- deflatePrime returns Z_OK if success, or Z_STREAM_ERROR if the source
- stream state was inconsistent.
-*/
-
-ZEXTERN int ZEXPORT deflateSetHeader OF((z_streamp strm,
- gz_headerp head));
-/*
- deflateSetHeader() provides gzip header information for when a gzip
- stream is requested by deflateInit2(). deflateSetHeader() may be called
- after deflateInit2() or deflateReset() and before the first call of
- deflate(). The text, time, os, extra field, name, and comment information
- in the provided gz_header structure are written to the gzip header (xflag is
- ignored -- the extra flags are set according to the compression level). The
- caller must assure that, if not Z_NULL, name and comment are terminated with
- a zero byte, and that if extra is not Z_NULL, that extra_len bytes are
- available there. If hcrc is true, a gzip header crc is included. Note that
- the current versions of the command-line version of gzip (up through version
- 1.3.x) do not support header crc's, and will report that it is a "multi-part
- gzip file" and give up.
-
- If deflateSetHeader is not used, the default gzip header has text false,
- the time set to zero, and os set to 255, with no extra, name, or comment
- fields. The gzip header is returned to the default state by deflateReset().
-
- deflateSetHeader returns Z_OK if success, or Z_STREAM_ERROR if the source
- stream state was inconsistent.
-*/
-
-/*
-ZEXTERN int ZEXPORT inflateInit2 OF((z_streamp strm,
- int windowBits));
-
- This is another version of inflateInit with an extra parameter. The
- fields next_in, avail_in, zalloc, zfree and opaque must be initialized
- before by the caller.
-
- The windowBits parameter is the base two logarithm of the maximum window
- size (the size of the history buffer). It should be in the range 8..15 for
- this version of the library. The default value is 15 if inflateInit is used
- instead. windowBits must be greater than or equal to the windowBits value
- provided to deflateInit2() while compressing, or it must be equal to 15 if
- deflateInit2() was not used. If a compressed stream with a larger window
- size is given as input, inflate() will return with the error code
- Z_DATA_ERROR instead of trying to allocate a larger window.
-
- windowBits can also be zero to request that inflate use the window size in
- the zlib header of the compressed stream.
-
- windowBits can also be -8..-15 for raw inflate. In this case, -windowBits
- determines the window size. inflate() will then process raw deflate data,
- not looking for a zlib or gzip header, not generating a check value, and not
- looking for any check values for comparison at the end of the stream. This
- is for use with other formats that use the deflate compressed data format
- such as zip. Those formats provide their own check values. If a custom
- format is developed using the raw deflate format for compressed data, it is
- recommended that a check value such as an adler32 or a crc32 be applied to
- the uncompressed data as is done in the zlib, gzip, and zip formats. For
- most applications, the zlib format should be used as is. Note that comments
- above on the use in deflateInit2() applies to the magnitude of windowBits.
-
- windowBits can also be greater than 15 for optional gzip decoding. Add
- 32 to windowBits to enable zlib and gzip decoding with automatic header
- detection, or add 16 to decode only the gzip format (the zlib format will
- return a Z_DATA_ERROR). If a gzip stream is being decoded, strm->adler is a
- crc32 instead of an adler32.
-
- inflateInit2 returns Z_OK if success, Z_MEM_ERROR if there was not enough
- memory, Z_VERSION_ERROR if the zlib library version is incompatible with the
- version assumed by the caller, or Z_STREAM_ERROR if the parameters are
- invalid, such as a null pointer to the structure. msg is set to null if
- there is no error message. inflateInit2 does not perform any decompression
- apart from possibly reading the zlib header if present: actual decompression
- will be done by inflate(). (So next_in and avail_in may be modified, but
- next_out and avail_out are unused and unchanged.) The current implementation
- of inflateInit2() does not process any header information -- that is
- deferred until inflate() is called.
-*/
-
-ZEXTERN int ZEXPORT inflateSetDictionary OF((z_streamp strm,
- const Bytef *dictionary,
- uInt dictLength));
-/*
- Initializes the decompression dictionary from the given uncompressed byte
- sequence. This function must be called immediately after a call of inflate,
- if that call returned Z_NEED_DICT. The dictionary chosen by the compressor
- can be determined from the adler32 value returned by that call of inflate.
- The compressor and decompressor must use exactly the same dictionary (see
- deflateSetDictionary). For raw inflate, this function can be called
- immediately after inflateInit2() or inflateReset() and before any call of
- inflate() to set the dictionary. The application must insure that the
- dictionary that was used for compression is provided.
-
- inflateSetDictionary returns Z_OK if success, Z_STREAM_ERROR if a
- parameter is invalid (e.g. dictionary being Z_NULL) or the stream state is
- inconsistent, Z_DATA_ERROR if the given dictionary doesn't match the
- expected one (incorrect adler32 value). inflateSetDictionary does not
- perform any decompression: this will be done by subsequent calls of
- inflate().
-*/
-
-ZEXTERN int ZEXPORT inflateSync OF((z_streamp strm));
-/*
- Skips invalid compressed data until a full flush point (see above the
- description of deflate with Z_FULL_FLUSH) can be found, or until all
- available input is skipped. No output is provided.
-
- inflateSync returns Z_OK if a full flush point has been found, Z_BUF_ERROR
- if no more input was provided, Z_DATA_ERROR if no flush point has been
- found, or Z_STREAM_ERROR if the stream structure was inconsistent. In the
- success case, the application may save the current current value of total_in
- which indicates where valid compressed data was found. In the error case,
- the application may repeatedly call inflateSync, providing more input each
- time, until success or end of the input data.
-*/
-
-ZEXTERN int ZEXPORT inflateCopy OF((z_streamp dest,
- z_streamp source));
-/*
- Sets the destination stream as a complete copy of the source stream.
-
- This function can be useful when randomly accessing a large stream. The
- first pass through the stream can periodically record the inflate state,
- allowing restarting inflate at those points when randomly accessing the
- stream.
-
- inflateCopy returns Z_OK if success, Z_MEM_ERROR if there was not
- enough memory, Z_STREAM_ERROR if the source stream state was inconsistent
- (such as zalloc being Z_NULL). msg is left unchanged in both source and
- destination.
-*/
-
-ZEXTERN int ZEXPORT inflateReset OF((z_streamp strm));
-/*
- This function is equivalent to inflateEnd followed by inflateInit,
- but does not free and reallocate all the internal decompression state. The
- stream will keep attributes that may have been set by inflateInit2.
-
- inflateReset returns Z_OK if success, or Z_STREAM_ERROR if the source
- stream state was inconsistent (such as zalloc or state being Z_NULL).
-*/
-
-ZEXTERN int ZEXPORT inflateReset2 OF((z_streamp strm,
- int windowBits));
-/*
- This function is the same as inflateReset, but it also permits changing
- the wrap and window size requests. The windowBits parameter is interpreted
- the same as it is for inflateInit2.
-
- inflateReset2 returns Z_OK if success, or Z_STREAM_ERROR if the source
- stream state was inconsistent (such as zalloc or state being Z_NULL), or if
- the windowBits parameter is invalid.
-*/
-
-ZEXTERN int ZEXPORT inflatePrime OF((z_streamp strm,
- int bits,
- int value));
-/*
- This function inserts bits in the inflate input stream. The intent is
- that this function is used to start inflating at a bit position in the
- middle of a byte. The provided bits will be used before any bytes are used
- from next_in. This function should only be used with raw inflate, and
- should be used before the first inflate() call after inflateInit2() or
- inflateReset(). bits must be less than or equal to 16, and that many of the
- least significant bits of value will be inserted in the input.
-
- If bits is negative, then the input stream bit buffer is emptied. Then
- inflatePrime() can be called again to put bits in the buffer. This is used
- to clear out bits leftover after feeding inflate a block description prior
- to feeding inflate codes.
-
- inflatePrime returns Z_OK if success, or Z_STREAM_ERROR if the source
- stream state was inconsistent.
-*/
-
-ZEXTERN long ZEXPORT inflateMark OF((z_streamp strm));
-/*
- This function returns two values, one in the lower 16 bits of the return
- value, and the other in the remaining upper bits, obtained by shifting the
- return value down 16 bits. If the upper value is -1 and the lower value is
- zero, then inflate() is currently decoding information outside of a block.
- If the upper value is -1 and the lower value is non-zero, then inflate is in
- the middle of a stored block, with the lower value equaling the number of
- bytes from the input remaining to copy. If the upper value is not -1, then
- it is the number of bits back from the current bit position in the input of
- the code (literal or length/distance pair) currently being processed. In
- that case the lower value is the number of bytes already emitted for that
- code.
-
- A code is being processed if inflate is waiting for more input to complete
- decoding of the code, or if it has completed decoding but is waiting for
- more output space to write the literal or match data.
-
- inflateMark() is used to mark locations in the input data for random
- access, which may be at bit positions, and to note those cases where the
- output of a code may span boundaries of random access blocks. The current
- location in the input stream can be determined from avail_in and data_type
- as noted in the description for the Z_BLOCK flush parameter for inflate.
-
- inflateMark returns the value noted above or -1 << 16 if the provided
- source stream state was inconsistent.
-*/
-
-ZEXTERN int ZEXPORT inflateGetHeader OF((z_streamp strm,
- gz_headerp head));
-/*
- inflateGetHeader() requests that gzip header information be stored in the
- provided gz_header structure. inflateGetHeader() may be called after
- inflateInit2() or inflateReset(), and before the first call of inflate().
- As inflate() processes the gzip stream, head->done is zero until the header
- is completed, at which time head->done is set to one. If a zlib stream is
- being decoded, then head->done is set to -1 to indicate that there will be
- no gzip header information forthcoming. Note that Z_BLOCK or Z_TREES can be
- used to force inflate() to return immediately after header processing is
- complete and before any actual data is decompressed.
-
- The text, time, xflags, and os fields are filled in with the gzip header
- contents. hcrc is set to true if there is a header CRC. (The header CRC
- was valid if done is set to one.) If extra is not Z_NULL, then extra_max
- contains the maximum number of bytes to write to extra. Once done is true,
- extra_len contains the actual extra field length, and extra contains the
- extra field, or that field truncated if extra_max is less than extra_len.
- If name is not Z_NULL, then up to name_max characters are written there,
- terminated with a zero unless the length is greater than name_max. If
- comment is not Z_NULL, then up to comm_max characters are written there,
- terminated with a zero unless the length is greater than comm_max. When any
- of extra, name, or comment are not Z_NULL and the respective field is not
- present in the header, then that field is set to Z_NULL to signal its
- absence. This allows the use of deflateSetHeader() with the returned
- structure to duplicate the header. However if those fields are set to
- allocated memory, then the application will need to save those pointers
- elsewhere so that they can be eventually freed.
-
- If inflateGetHeader is not used, then the header information is simply
- discarded. The header is always checked for validity, including the header
- CRC if present. inflateReset() will reset the process to discard the header
- information. The application would need to call inflateGetHeader() again to
- retrieve the header from the next gzip stream.
-
- inflateGetHeader returns Z_OK if success, or Z_STREAM_ERROR if the source
- stream state was inconsistent.
-*/
-
-/*
-ZEXTERN int ZEXPORT inflateBackInit OF((z_streamp strm, int windowBits,
- unsigned char FAR *window));
-
- Initialize the internal stream state for decompression using inflateBack()
- calls. The fields zalloc, zfree and opaque in strm must be initialized
- before the call. If zalloc and zfree are Z_NULL, then the default library-
- derived memory allocation routines are used. windowBits is the base two
- logarithm of the window size, in the range 8..15. window is a caller
- supplied buffer of that size. Except for special applications where it is
- assured that deflate was used with small window sizes, windowBits must be 15
- and a 32K byte window must be supplied to be able to decompress general
- deflate streams.
-
- See inflateBack() for the usage of these routines.
-
- inflateBackInit will return Z_OK on success, Z_STREAM_ERROR if any of
- the paramaters are invalid, Z_MEM_ERROR if the internal state could not be
- allocated, or Z_VERSION_ERROR if the version of the library does not match
- the version of the header file.
-*/
-
-typedef unsigned (*in_func) OF((void FAR *, unsigned char FAR * FAR *));
-typedef int (*out_func) OF((void FAR *, unsigned char FAR *, unsigned));
-
-ZEXTERN int ZEXPORT inflateBack OF((z_streamp strm,
- in_func in, void FAR *in_desc,
- out_func out, void FAR *out_desc));
-/*
- inflateBack() does a raw inflate with a single call using a call-back
- interface for input and output. This is more efficient than inflate() for
- file i/o applications in that it avoids copying between the output and the
- sliding window by simply making the window itself the output buffer. This
- function trusts the application to not change the output buffer passed by
- the output function, at least until inflateBack() returns.
-
- inflateBackInit() must be called first to allocate the internal state
- and to initialize the state with the user-provided window buffer.
- inflateBack() may then be used multiple times to inflate a complete, raw
- deflate stream with each call. inflateBackEnd() is then called to free the
- allocated state.
-
- A raw deflate stream is one with no zlib or gzip header or trailer.
- This routine would normally be used in a utility that reads zip or gzip
- files and writes out uncompressed files. The utility would decode the
- header and process the trailer on its own, hence this routine expects only
- the raw deflate stream to decompress. This is different from the normal
- behavior of inflate(), which expects either a zlib or gzip header and
- trailer around the deflate stream.
-
- inflateBack() uses two subroutines supplied by the caller that are then
- called by inflateBack() for input and output. inflateBack() calls those
- routines until it reads a complete deflate stream and writes out all of the
- uncompressed data, or until it encounters an error. The function's
- parameters and return types are defined above in the in_func and out_func
- typedefs. inflateBack() will call in(in_desc, &buf) which should return the
- number of bytes of provided input, and a pointer to that input in buf. If
- there is no input available, in() must return zero--buf is ignored in that
- case--and inflateBack() will return a buffer error. inflateBack() will call
- out(out_desc, buf, len) to write the uncompressed data buf[0..len-1]. out()
- should return zero on success, or non-zero on failure. If out() returns
- non-zero, inflateBack() will return with an error. Neither in() nor out()
- are permitted to change the contents of the window provided to
- inflateBackInit(), which is also the buffer that out() uses to write from.
- The length written by out() will be at most the window size. Any non-zero
- amount of input may be provided by in().
-
- For convenience, inflateBack() can be provided input on the first call by
- setting strm->next_in and strm->avail_in. If that input is exhausted, then
- in() will be called. Therefore strm->next_in must be initialized before
- calling inflateBack(). If strm->next_in is Z_NULL, then in() will be called
- immediately for input. If strm->next_in is not Z_NULL, then strm->avail_in
- must also be initialized, and then if strm->avail_in is not zero, input will
- initially be taken from strm->next_in[0 .. strm->avail_in - 1].
-
- The in_desc and out_desc parameters of inflateBack() is passed as the
- first parameter of in() and out() respectively when they are called. These
- descriptors can be optionally used to pass any information that the caller-
- supplied in() and out() functions need to do their job.
-
- On return, inflateBack() will set strm->next_in and strm->avail_in to
- pass back any unused input that was provided by the last in() call. The
- return values of inflateBack() can be Z_STREAM_END on success, Z_BUF_ERROR
- if in() or out() returned an error, Z_DATA_ERROR if there was a format error
- in the deflate stream (in which case strm->msg is set to indicate the nature
- of the error), or Z_STREAM_ERROR if the stream was not properly initialized.
- In the case of Z_BUF_ERROR, an input or output error can be distinguished
- using strm->next_in which will be Z_NULL only if in() returned an error. If
- strm->next_in is not Z_NULL, then the Z_BUF_ERROR was due to out() returning
- non-zero. (in() will always be called before out(), so strm->next_in is
- assured to be defined if out() returns non-zero.) Note that inflateBack()
- cannot return Z_OK.
-*/
-
-ZEXTERN int ZEXPORT inflateBackEnd OF((z_streamp strm));
-/*
- All memory allocated by inflateBackInit() is freed.
-
- inflateBackEnd() returns Z_OK on success, or Z_STREAM_ERROR if the stream
- state was inconsistent.
-*/
-
-ZEXTERN uLong ZEXPORT zlibCompileFlags OF((void));
-/* Return flags indicating compile-time options.
-
- Type sizes, two bits each, 00 = 16 bits, 01 = 32, 10 = 64, 11 = other:
- 1.0: size of uInt
- 3.2: size of uLong
- 5.4: size of voidpf (pointer)
- 7.6: size of z_off_t
-
- Compiler, assembler, and debug options:
- 8: DEBUG
- 9: ASMV or ASMINF -- use ASM code
- 10: ZLIB_WINAPI -- exported functions use the WINAPI calling convention
- 11: 0 (reserved)
-
- One-time table building (smaller code, but not thread-safe if true):
- 12: BUILDFIXED -- build static block decoding tables when needed
- 13: DYNAMIC_CRC_TABLE -- build CRC calculation tables when needed
- 14,15: 0 (reserved)
-
- Library content (indicates missing functionality):
- 16: NO_GZCOMPRESS -- gz* functions cannot compress (to avoid linking
- deflate code when not needed)
- 17: NO_GZIP -- deflate can't write gzip streams, and inflate can't detect
- and decode gzip streams (to avoid linking crc code)
- 18-19: 0 (reserved)
-
- Operation variations (changes in library functionality):
- 20: PKZIP_BUG_WORKAROUND -- slightly more permissive inflate
- 21: FASTEST -- deflate algorithm with only one, lowest compression level
- 22,23: 0 (reserved)
-
- The sprintf variant used by gzprintf (zero is best):
- 24: 0 = vs*, 1 = s* -- 1 means limited to 20 arguments after the format
- 25: 0 = *nprintf, 1 = *printf -- 1 means gzprintf() not secure!
- 26: 0 = returns value, 1 = void -- 1 means inferred string length returned
-
- Remainder:
- 27-31: 0 (reserved)
- */
-
-
- /* utility functions */
-
-/*
- The following utility functions are implemented on top of the basic
- stream-oriented functions. To simplify the interface, some default options
- are assumed (compression level and memory usage, standard memory allocation
- functions). The source code of these utility functions can be modified if
- you need special options.
-*/
-
-ZEXTERN int ZEXPORT compress OF((Bytef *dest, uLongf *destLen,
- const Bytef *source, uLong sourceLen));
-/*
- Compresses the source buffer into the destination buffer. sourceLen is
- the byte length of the source buffer. Upon entry, destLen is the total size
- of the destination buffer, which must be at least the value returned by
- compressBound(sourceLen). Upon exit, destLen is the actual size of the
- compressed buffer.
-
- compress returns Z_OK if success, Z_MEM_ERROR if there was not
- enough memory, Z_BUF_ERROR if there was not enough room in the output
- buffer.
-*/
-
-ZEXTERN int ZEXPORT compress2 OF((Bytef *dest, uLongf *destLen,
- const Bytef *source, uLong sourceLen,
- int level));
-/*
- Compresses the source buffer into the destination buffer. The level
- parameter has the same meaning as in deflateInit. sourceLen is the byte
- length of the source buffer. Upon entry, destLen is the total size of the
- destination buffer, which must be at least the value returned by
- compressBound(sourceLen). Upon exit, destLen is the actual size of the
- compressed buffer.
-
- compress2 returns Z_OK if success, Z_MEM_ERROR if there was not enough
- memory, Z_BUF_ERROR if there was not enough room in the output buffer,
- Z_STREAM_ERROR if the level parameter is invalid.
-*/
-
-ZEXTERN uLong ZEXPORT compressBound OF((uLong sourceLen));
-/*
- compressBound() returns an upper bound on the compressed size after
- compress() or compress2() on sourceLen bytes. It would be used before a
- compress() or compress2() call to allocate the destination buffer.
-*/
-
-ZEXTERN int ZEXPORT uncompress OF((Bytef *dest, uLongf *destLen,
- const Bytef *source, uLong sourceLen));
-/*
- Decompresses the source buffer into the destination buffer. sourceLen is
- the byte length of the source buffer. Upon entry, destLen is the total size
- of the destination buffer, which must be large enough to hold the entire
- uncompressed data. (The size of the uncompressed data must have been saved
- previously by the compressor and transmitted to the decompressor by some
- mechanism outside the scope of this compression library.) Upon exit, destLen
- is the actual size of the uncompressed buffer.
-
- uncompress returns Z_OK if success, Z_MEM_ERROR if there was not
- enough memory, Z_BUF_ERROR if there was not enough room in the output
- buffer, or Z_DATA_ERROR if the input data was corrupted or incomplete.
-*/
-
-
- /* gzip file access functions */
-
-/*
- This library supports reading and writing files in gzip (.gz) format with
- an interface similar to that of stdio, using the functions that start with
- "gz". The gzip format is different from the zlib format. gzip is a gzip
- wrapper, documented in RFC 1952, wrapped around a deflate stream.
-*/
-
-typedef voidp gzFile; /* opaque gzip file descriptor */
-
-/*
-ZEXTERN gzFile ZEXPORT gzopen OF((const char *path, const char *mode));
-
- Opens a gzip (.gz) file for reading or writing. The mode parameter is as
- in fopen ("rb" or "wb") but can also include a compression level ("wb9") or
- a strategy: 'f' for filtered data as in "wb6f", 'h' for Huffman-only
- compression as in "wb1h", 'R' for run-length encoding as in "wb1R", or 'F'
- for fixed code compression as in "wb9F". (See the description of
- deflateInit2 for more information about the strategy parameter.) Also "a"
- can be used instead of "w" to request that the gzip stream that will be
- written be appended to the file. "+" will result in an error, since reading
- and writing to the same gzip file is not supported.
-
- gzopen can be used to read a file which is not in gzip format; in this
- case gzread will directly read from the file without decompression.
-
- gzopen returns NULL if the file could not be opened, if there was
- insufficient memory to allocate the gzFile state, or if an invalid mode was
- specified (an 'r', 'w', or 'a' was not provided, or '+' was provided).
- errno can be checked to determine if the reason gzopen failed was that the
- file could not be opened.
-*/
-
-ZEXTERN gzFile ZEXPORT gzdopen OF((int fd, const char *mode));
-/*
- gzdopen associates a gzFile with the file descriptor fd. File descriptors
- are obtained from calls like open, dup, creat, pipe or fileno (if the file
- has been previously opened with fopen). The mode parameter is as in gzopen.
-
- The next call of gzclose on the returned gzFile will also close the file
- descriptor fd, just like fclose(fdopen(fd, mode)) closes the file descriptor
- fd. If you want to keep fd open, use fd = dup(fd_keep); gz = gzdopen(fd,
- mode);. The duplicated descriptor should be saved to avoid a leak, since
- gzdopen does not close fd if it fails.
-
- gzdopen returns NULL if there was insufficient memory to allocate the
- gzFile state, if an invalid mode was specified (an 'r', 'w', or 'a' was not
- provided, or '+' was provided), or if fd is -1. The file descriptor is not
- used until the next gz* read, write, seek, or close operation, so gzdopen
- will not detect if fd is invalid (unless fd is -1).
-*/
-
-ZEXTERN int ZEXPORT gzbuffer OF((gzFile file, unsigned size));
-/*
- Set the internal buffer size used by this library's functions. The
- default buffer size is 8192 bytes. This function must be called after
- gzopen() or gzdopen(), and before any other calls that read or write the
- file. The buffer memory allocation is always deferred to the first read or
- write. Two buffers are allocated, either both of the specified size when
- writing, or one of the specified size and the other twice that size when
- reading. A larger buffer size of, for example, 64K or 128K bytes will
- noticeably increase the speed of decompression (reading).
-
- The new buffer size also affects the maximum length for gzprintf().
-
- gzbuffer() returns 0 on success, or -1 on failure, such as being called
- too late.
-*/
-
-ZEXTERN int ZEXPORT gzsetparams OF((gzFile file, int level, int strategy));
-/*
- Dynamically update the compression level or strategy. See the description
- of deflateInit2 for the meaning of these parameters.
-
- gzsetparams returns Z_OK if success, or Z_STREAM_ERROR if the file was not
- opened for writing.
-*/
-
-ZEXTERN int ZEXPORT gzread OF((gzFile file, voidp buf, unsigned len));
-/*
- Reads the given number of uncompressed bytes from the compressed file. If
- the input file was not in gzip format, gzread copies the given number of
- bytes into the buffer.
-
- After reaching the end of a gzip stream in the input, gzread will continue
- to read, looking for another gzip stream, or failing that, reading the rest
- of the input file directly without decompression. The entire input file
- will be read if gzread is called until it returns less than the requested
- len.
-
- gzread returns the number of uncompressed bytes actually read, less than
- len for end of file, or -1 for error.
-*/
-
-ZEXTERN int ZEXPORT gzwrite OF((gzFile file,
- voidpc buf, unsigned len));
-/*
- Writes the given number of uncompressed bytes into the compressed file.
- gzwrite returns the number of uncompressed bytes written or 0 in case of
- error.
-*/
-
-ZEXTERN int ZEXPORTVA gzprintf OF((gzFile file, const char *format, ...));
-/*
- Converts, formats, and writes the arguments to the compressed file under
- control of the format string, as in fprintf. gzprintf returns the number of
- uncompressed bytes actually written, or 0 in case of error. The number of
- uncompressed bytes written is limited to 8191, or one less than the buffer
- size given to gzbuffer(). The caller should assure that this limit is not
- exceeded. If it is exceeded, then gzprintf() will return an error (0) with
- nothing written. In this case, there may also be a buffer overflow with
- unpredictable consequences, which is possible only if zlib was compiled with
- the insecure functions sprintf() or vsprintf() because the secure snprintf()
- or vsnprintf() functions were not available. This can be determined using
- zlibCompileFlags().
-*/
-
-ZEXTERN int ZEXPORT gzputs OF((gzFile file, const char *s));
-/*
- Writes the given null-terminated string to the compressed file, excluding
- the terminating null character.
-
- gzputs returns the number of characters written, or -1 in case of error.
-*/
-
-ZEXTERN char * ZEXPORT gzgets OF((gzFile file, char *buf, int len));
-/*
- Reads bytes from the compressed file until len-1 characters are read, or a
- newline character is read and transferred to buf, or an end-of-file
- condition is encountered. If any characters are read or if len == 1, the
- string is terminated with a null character. If no characters are read due
- to an end-of-file or len < 1, then the buffer is left untouched.
-
- gzgets returns buf which is a null-terminated string, or it returns NULL
- for end-of-file or in case of error. If there was an error, the contents at
- buf are indeterminate.
-*/
-
-ZEXTERN int ZEXPORT gzputc OF((gzFile file, int c));
-/*
- Writes c, converted to an unsigned char, into the compressed file. gzputc
- returns the value that was written, or -1 in case of error.
-*/
-
-ZEXTERN int ZEXPORT gzgetc OF((gzFile file));
-/*
- Reads one byte from the compressed file. gzgetc returns this byte or -1
- in case of end of file or error.
-*/
-
-ZEXTERN int ZEXPORT gzungetc OF((int c, gzFile file));
-/*
- Push one character back onto the stream to be read as the first character
- on the next read. At least one character of push-back is allowed.
- gzungetc() returns the character pushed, or -1 on failure. gzungetc() will
- fail if c is -1, and may fail if a character has been pushed but not read
- yet. If gzungetc is used immediately after gzopen or gzdopen, at least the
- output buffer size of pushed characters is allowed. (See gzbuffer above.)
- The pushed character will be discarded if the stream is repositioned with
- gzseek() or gzrewind().
-*/
-
-ZEXTERN int ZEXPORT gzflush OF((gzFile file, int flush));
-/*
- Flushes all pending output into the compressed file. The parameter flush
- is as in the deflate() function. The return value is the zlib error number
- (see function gzerror below). gzflush is only permitted when writing.
-
- If the flush parameter is Z_FINISH, the remaining data is written and the
- gzip stream is completed in the output. If gzwrite() is called again, a new
- gzip stream will be started in the output. gzread() is able to read such
- concatented gzip streams.
-
- gzflush should be called only when strictly necessary because it will
- degrade compression if called too often.
-*/
-
-/*
-ZEXTERN z_off_t ZEXPORT gzseek OF((gzFile file,
- z_off_t offset, int whence));
-
- Sets the starting position for the next gzread or gzwrite on the given
- compressed file. The offset represents a number of bytes in the
- uncompressed data stream. The whence parameter is defined as in lseek(2);
- the value SEEK_END is not supported.
-
- If the file is opened for reading, this function is emulated but can be
- extremely slow. If the file is opened for writing, only forward seeks are
- supported; gzseek then compresses a sequence of zeroes up to the new
- starting position.
-
- gzseek returns the resulting offset location as measured in bytes from
- the beginning of the uncompressed stream, or -1 in case of error, in
- particular if the file is opened for writing and the new starting position
- would be before the current position.
-*/
-
-ZEXTERN int ZEXPORT gzrewind OF((gzFile file));
-/*
- Rewinds the given file. This function is supported only for reading.
-
- gzrewind(file) is equivalent to (int)gzseek(file, 0L, SEEK_SET)
-*/
-
-/*
-ZEXTERN z_off_t ZEXPORT gztell OF((gzFile file));
-
- Returns the starting position for the next gzread or gzwrite on the given
- compressed file. This position represents a number of bytes in the
- uncompressed data stream, and is zero when starting, even if appending or
- reading a gzip stream from the middle of a file using gzdopen().
-
- gztell(file) is equivalent to gzseek(file, 0L, SEEK_CUR)
-*/
-
-/*
-ZEXTERN z_off_t ZEXPORT gzoffset OF((gzFile file));
-
- Returns the current offset in the file being read or written. This offset
- includes the count of bytes that precede the gzip stream, for example when
- appending or when using gzdopen() for reading. When reading, the offset
- does not include as yet unused buffered input. This information can be used
- for a progress indicator. On error, gzoffset() returns -1.
-*/
-
-ZEXTERN int ZEXPORT gzeof OF((gzFile file));
-/*
- Returns true (1) if the end-of-file indicator has been set while reading,
- false (0) otherwise. Note that the end-of-file indicator is set only if the
- read tried to go past the end of the input, but came up short. Therefore,
- just like feof(), gzeof() may return false even if there is no more data to
- read, in the event that the last read request was for the exact number of
- bytes remaining in the input file. This will happen if the input file size
- is an exact multiple of the buffer size.
-
- If gzeof() returns true, then the read functions will return no more data,
- unless the end-of-file indicator is reset by gzclearerr() and the input file
- has grown since the previous end of file was detected.
-*/
-
-ZEXTERN int ZEXPORT gzdirect OF((gzFile file));
-/*
- Returns true (1) if file is being copied directly while reading, or false
- (0) if file is a gzip stream being decompressed. This state can change from
- false to true while reading the input file if the end of a gzip stream is
- reached, but is followed by data that is not another gzip stream.
-
- If the input file is empty, gzdirect() will return true, since the input
- does not contain a gzip stream.
-
- If gzdirect() is used immediately after gzopen() or gzdopen() it will
- cause buffers to be allocated to allow reading the file to determine if it
- is a gzip file. Therefore if gzbuffer() is used, it should be called before
- gzdirect().
-*/
-
-ZEXTERN int ZEXPORT gzclose OF((gzFile file));
-/*
- Flushes all pending output if necessary, closes the compressed file and
- deallocates the (de)compression state. Note that once file is closed, you
- cannot call gzerror with file, since its structures have been deallocated.
- gzclose must not be called more than once on the same file, just as free
- must not be called more than once on the same allocation.
-
- gzclose will return Z_STREAM_ERROR if file is not valid, Z_ERRNO on a
- file operation error, or Z_OK on success.
-*/
-
-ZEXTERN int ZEXPORT gzclose_r OF((gzFile file));
-ZEXTERN int ZEXPORT gzclose_w OF((gzFile file));
-/*
- Same as gzclose(), but gzclose_r() is only for use when reading, and
- gzclose_w() is only for use when writing or appending. The advantage to
- using these instead of gzclose() is that they avoid linking in zlib
- compression or decompression code that is not used when only reading or only
- writing respectively. If gzclose() is used, then both compression and
- decompression code will be included the application when linking to a static
- zlib library.
-*/
-
-ZEXTERN const char * ZEXPORT gzerror OF((gzFile file, int *errnum));
-/*
- Returns the error message for the last error which occurred on the given
- compressed file. errnum is set to zlib error number. If an error occurred
- in the file system and not in the compression library, errnum is set to
- Z_ERRNO and the application may consult errno to get the exact error code.
-
- The application must not modify the returned string. Future calls to
- this function may invalidate the previously returned string. If file is
- closed, then the string previously returned by gzerror will no longer be
- available.
-
- gzerror() should be used to distinguish errors from end-of-file for those
- functions above that do not distinguish those cases in their return values.
-*/
-
-ZEXTERN void ZEXPORT gzclearerr OF((gzFile file));
-/*
- Clears the error and end-of-file flags for file. This is analogous to the
- clearerr() function in stdio. This is useful for continuing to read a gzip
- file that is being written concurrently.
-*/
-
-
- /* checksum functions */
-
-/*
- These functions are not related to compression but are exported
- anyway because they might be useful in applications using the compression
- library.
-*/
-
-ZEXTERN uLong ZEXPORT adler32 OF((uLong adler, const Bytef *buf, uInt len));
-/*
- Update a running Adler-32 checksum with the bytes buf[0..len-1] and
- return the updated checksum. If buf is Z_NULL, this function returns the
- required initial value for the checksum.
-
- An Adler-32 checksum is almost as reliable as a CRC32 but can be computed
- much faster.
-
- Usage example:
-
- uLong adler = adler32(0L, Z_NULL, 0);
-
- while (read_buffer(buffer, length) != EOF) {
- adler = adler32(adler, buffer, length);
- }
- if (adler != original_adler) error();
-*/
-
-/*
-ZEXTERN uLong ZEXPORT adler32_combine OF((uLong adler1, uLong adler2,
- z_off_t len2));
-
- Combine two Adler-32 checksums into one. For two sequences of bytes, seq1
- and seq2 with lengths len1 and len2, Adler-32 checksums were calculated for
- each, adler1 and adler2. adler32_combine() returns the Adler-32 checksum of
- seq1 and seq2 concatenated, requiring only adler1, adler2, and len2.
-*/
-
-ZEXTERN uLong ZEXPORT crc32 OF((uLong crc, const Bytef *buf, uInt len));
-/*
- Update a running CRC-32 with the bytes buf[0..len-1] and return the
- updated CRC-32. If buf is Z_NULL, this function returns the required
- initial value for the for the crc. Pre- and post-conditioning (one's
- complement) is performed within this function so it shouldn't be done by the
- application.
-
- Usage example:
-
- uLong crc = crc32(0L, Z_NULL, 0);
-
- while (read_buffer(buffer, length) != EOF) {
- crc = crc32(crc, buffer, length);
- }
- if (crc != original_crc) error();
-*/
-
-/*
-ZEXTERN uLong ZEXPORT crc32_combine OF((uLong crc1, uLong crc2, z_off_t len2));
-
- Combine two CRC-32 check values into one. For two sequences of bytes,
- seq1 and seq2 with lengths len1 and len2, CRC-32 check values were
- calculated for each, crc1 and crc2. crc32_combine() returns the CRC-32
- check value of seq1 and seq2 concatenated, requiring only crc1, crc2, and
- len2.
-*/
-
-
- /* various hacks, don't look :) */
-
-/* deflateInit and inflateInit are macros to allow checking the zlib version
- * and the compiler's view of z_stream:
- */
-ZEXTERN int ZEXPORT deflateInit_ OF((z_streamp strm, int level,
- const char *version, int stream_size));
-ZEXTERN int ZEXPORT inflateInit_ OF((z_streamp strm,
- const char *version, int stream_size));
-ZEXTERN int ZEXPORT deflateInit2_ OF((z_streamp strm, int level, int method,
- int windowBits, int memLevel,
- int strategy, const char *version,
- int stream_size));
-ZEXTERN int ZEXPORT inflateInit2_ OF((z_streamp strm, int windowBits,
- const char *version, int stream_size));
-ZEXTERN int ZEXPORT inflateBackInit_ OF((z_streamp strm, int windowBits,
- unsigned char FAR *window,
- const char *version,
- int stream_size));
-#define deflateInit(strm, level) \
- deflateInit_((strm), (level), ZLIB_VERSION, sizeof(z_stream))
-#define inflateInit(strm) \
- inflateInit_((strm), ZLIB_VERSION, sizeof(z_stream))
-#define deflateInit2(strm, level, method, windowBits, memLevel, strategy) \
- deflateInit2_((strm),(level),(method),(windowBits),(memLevel),\
- (strategy), ZLIB_VERSION, sizeof(z_stream))
-#define inflateInit2(strm, windowBits) \
- inflateInit2_((strm), (windowBits), ZLIB_VERSION, sizeof(z_stream))
-#define inflateBackInit(strm, windowBits, window) \
- inflateBackInit_((strm), (windowBits), (window), \
- ZLIB_VERSION, sizeof(z_stream))
-
-/* provide 64-bit offset functions if _LARGEFILE64_SOURCE defined, and/or
- * change the regular functions to 64 bits if _FILE_OFFSET_BITS is 64 (if
- * both are true, the application gets the *64 functions, and the regular
- * functions are changed to 64 bits) -- in case these are set on systems
- * without large file support, _LFS64_LARGEFILE must also be true
- */
-#if defined(_LARGEFILE64_SOURCE) && _LFS64_LARGEFILE-0
- ZEXTERN gzFile ZEXPORT gzopen64 OF((const char *, const char *));
- ZEXTERN z_off64_t ZEXPORT gzseek64 OF((gzFile, z_off64_t, int));
- ZEXTERN z_off64_t ZEXPORT gztell64 OF((gzFile));
- ZEXTERN z_off64_t ZEXPORT gzoffset64 OF((gzFile));
- ZEXTERN uLong ZEXPORT adler32_combine64 OF((uLong, uLong, z_off64_t));
- ZEXTERN uLong ZEXPORT crc32_combine64 OF((uLong, uLong, z_off64_t));
-#endif
-
-#if !defined(ZLIB_INTERNAL) && _FILE_OFFSET_BITS-0 == 64 && _LFS64_LARGEFILE-0
-# define gzopen gzopen64
-# define gzseek gzseek64
-# define gztell gztell64
-# define gzoffset gzoffset64
-# define adler32_combine adler32_combine64
-# define crc32_combine crc32_combine64
-# ifdef _LARGEFILE64_SOURCE
- ZEXTERN gzFile ZEXPORT gzopen64 OF((const char *, const char *));
- ZEXTERN z_off_t ZEXPORT gzseek64 OF((gzFile, z_off_t, int));
- ZEXTERN z_off_t ZEXPORT gztell64 OF((gzFile));
- ZEXTERN z_off_t ZEXPORT gzoffset64 OF((gzFile));
- ZEXTERN uLong ZEXPORT adler32_combine64 OF((uLong, uLong, z_off_t));
- ZEXTERN uLong ZEXPORT crc32_combine64 OF((uLong, uLong, z_off_t));
-# endif
-#else
- ZEXTERN gzFile ZEXPORT gzopen OF((const char *, const char *));
- ZEXTERN z_off_t ZEXPORT gzseek OF((gzFile, z_off_t, int));
- ZEXTERN z_off_t ZEXPORT gztell OF((gzFile));
- ZEXTERN z_off_t ZEXPORT gzoffset OF((gzFile));
- ZEXTERN uLong ZEXPORT adler32_combine OF((uLong, uLong, z_off_t));
- ZEXTERN uLong ZEXPORT crc32_combine OF((uLong, uLong, z_off_t));
-#endif
-
-/* hack for buggy compilers */
-#if !defined(ZUTIL_H) && !defined(NO_DUMMY_DECL)
- struct internal_state {int dummy;};
-#endif
-
-/* undocumented functions */
-ZEXTERN const char * ZEXPORT zError OF((int));
-ZEXTERN int ZEXPORT inflateSyncPoint OF((z_streamp));
-ZEXTERN const uLongf * ZEXPORT get_crc_table OF((void));
-ZEXTERN int ZEXPORT inflateUndermine OF((z_streamp, int));
-
-#ifdef __cplusplus
-}
-#endif
-
-#endif /* ZLIB_H */