zlib.h

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#ifndef _COMPAT_ZLIB_H
#define _COMPAT_ZLIB_H

#ifdef WANT_ZLIB

#ifdef RARCH_INTERNAL
#include "zconf.h.in"
#endif

/* zlib.h -- interface of the 'zlib' general purpose compression library
 version 1.2.8, April 28th, 2013

 Copyright (C) 1995-2013 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
 [email protected] [email protected]


 The data format used by the zlib library is described by RFCs (Request for
 Comments) 1950 to 1952 in the files http://tools.ietf.org/html/rfc1950
 (zlib format), rfc1951 (deflate format) and rfc1952 (gzip format).
*/

#ifndef ZLIB_H
#define ZLIB_H

#include <stdint.h>
#include "zconf.h"

#ifdef __cplusplus
extern "C" {
#endif

#define ZLIB_VERSION "1.2.8"
#define ZLIB_VERNUM 0x1280
#define ZLIB_VER_MAJOR 1
#define ZLIB_VER_MINOR 2
#define ZLIB_VER_REVISION 8
#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) (voidpf opaque, uInt items, uInt size);
typedef void (*free_func) (voidpf opaque, voidpf address);

struct internal_state;

typedef struct z_stream_s {
 z_const Bytef *next_in; /* next input byte */
 uInt avail_in; /* number of bytes available at next_in */
 uLong total_in; /* total number 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 number of bytes output so far */

 z_const char *msg; /* last error message, NULL if no error */
 void *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 */

 const char * zlibVersion (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.
 */

/*
 int deflateInit (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().
*/


 int deflate (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). Then deflate is guaranteed to
 return Z_STREAM_END. If not enough output space is provided, deflate will
 not return Z_STREAM_END, and 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.
*/


 int deflateEnd (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).
*/


/*
 int inflateInit (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.
*/


 int inflate (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 of the uncompressed data for the
 operation to complete. (The size of the uncompressed data may have been
 saved by the compressor for this purpose.) The use of Z_FINISH is not
 required to perform an inflation in one step. However it may be used to
 inform inflate that a faster approach can be used for the single inflate()
 call. Z_FINISH also informs inflate to not maintain a sliding window if the
 stream completes, which reduces inflate's memory footprint. If the stream
 does not complete, either because not all of the stream is provided or not
 enough output space is provided, then a sliding window will be allocated and
 inflate() can be called again to continue the operation as if Z_NO_FLUSH had
 been used.

 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 effects of the flush parameter in this implementation are
 on the return value of inflate() as noted below, when inflate() returns early
 when Z_BLOCK or Z_TREES is used, and when inflate() avoids the allocation of
 memory for a sliding window when Z_FINISH is used.

 If a preset dictionary is needed after this call (see inflateSetDictionary
 below), inflate sets strm->adler to the Adler-32 checksum of the dictionary
 chosen by the compressor and returns Z_NEED_DICT; otherwise it sets
 strm->adler to the Adler-32 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. When processing
 gzip-wrapped deflate data, strm->adler32 is set to the CRC-32 of the output
 producted so far. The CRC-32 is checked against the gzip 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.
*/


 int inflateEnd (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.
*/

/*
 int deflateInit2 (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().
*/

 int deflateSetDictionary (z_streamp strm,
 const Bytef *dictionary,
 uInt dictLength);
/*
 Initializes the compression dictionary from the given byte sequence
 without producing any compressed output. When using the zlib format, this
 function must be called immediately after deflateInit, deflateInit2 or
 deflateReset, and before any call of deflate. When doing raw deflate, this
 function must be called either before any call of deflate, or immediately
 after the completion of a deflate block, i.e. after all input has been
 consumed and all output has been delivered when using any of the flush
 options Z_BLOCK, Z_PARTIAL_FLUSH, Z_SYNC_FLUSH, or Z_FULL_FLUSH. 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 not at a block boundary for raw deflate). deflateSetDictionary does
 not perform any compression: this will be done by deflate().
*/

 int deflateCopy (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.
*/

 int deflateReset (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).
*/

 int deflateParams (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.
*/

 int deflateTune (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.
 */

 uLong deflateBound (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(). If that first deflate() call is provided the
 sourceLen input bytes, an output buffer allocated to the size returned by
 deflateBound(), and the flush value Z_FINISH, then deflate() is guaranteed
 to return Z_STREAM_END. Note that it is possible for the compressed size to
 be larger than the value returned by deflateBound() if flush options other
 than Z_FINISH or Z_NO_FLUSH are used.
*/

 int deflatePending (z_streamp strm,
 unsigned *pending,
 int *bits);
/*
 deflatePending() returns the number of bytes and bits of output that have
 been generated, but not yet provided in the available output. The bytes not
 provided would be due to the available output space having being consumed.
 The number of bits of output not provided are between 0 and 7, where they
 await more bits to join them in order to fill out a full byte. If pending
 or bits are Z_NULL, then those values are not set.

 deflatePending returns Z_OK if success, or Z_STREAM_ERROR if the source
 stream state was inconsistent.
 */

 int deflatePrime (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, Z_BUF_ERROR if there was not enough
 room in the internal buffer to insert the bits, or Z_STREAM_ERROR if the
 source stream state was inconsistent.
*/

 int deflateSetHeader (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.
*/

/*
 int inflateInit2 (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.
*/

 int inflateSetDictionary (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 at any
 time to set the dictionary. If the provided dictionary is smaller than the
 window and there is already data in the window, then the provided dictionary
 will amend what's there. 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().
*/

 int inflateGetDictionary (z_streamp strm,
 Bytef *dictionary,
 uInt *dictLength);
/*
 Returns the sliding dictionary being maintained by inflate. dictLength is
 set to the number of bytes in the dictionary, and that many bytes are copied
 to dictionary. dictionary must have enough space, where 32768 bytes is
 always enough. If inflateGetDictionary() is called with dictionary equal to
 Z_NULL, then only the dictionary length is returned, and nothing is copied.
 Similary, if dictLength is Z_NULL, then it is not set.

 inflateGetDictionary returns Z_OK on success, or Z_STREAM_ERROR if the
 stream state is inconsistent.
*/

 int inflateSync (z_streamp strm);
/*
 Skips invalid compressed data until a possible full flush point (see above
 for the description of deflate with Z_FULL_FLUSH) can be found, or until all
 available input is skipped. No output is provided.

 inflateSync searches for a 00 00 FF FF pattern in the compressed data.
 All full flush points have this pattern, but not all occurrences of this
 pattern are full flush points.

 inflateSync returns Z_OK if a possible 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.
*/

 int inflateCopy (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.
*/

 int inflateReset (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).
*/

 int inflateReset2 (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.
*/

 int inflatePrime (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.
*/

 long inflateMark (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.
*/

 int inflateGetHeader (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.
*/

/*
 int inflateBackInit (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 parameters 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) (void FAR *,
 z_const unsigned char FAR * FAR *);
typedef int (*out_func) (void FAR *, unsigned char FAR *, unsigned);

 int inflateBack (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 potentially 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. inflate() can be faster on modern CPUs when used with large
 buffers. inflateBack() 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.
*/

 int inflateBackEnd (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.
*/

 uLong zlibCompileFlags (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)
 */

#ifndef Z_SOLO

 /* 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.
*/

 int compress (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.
*/

 int compress2 (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.
*/

 uLong compressBound (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.
*/

 int uncompress (unsigned char *dest, uint32_t *destLen,
 const unsigned char *source, uint32_t 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. In
 the case where there is not enough room, uncompress() will fill the output
 buffer with the uncompressed data up to that point.
*/

 /* 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 struct gzFile_s *gzFile; /* semi-opaque gzip file descriptor */

/*
 gzFile gzopen (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.) 'T' will
 request transparent writing or appending with no compression and not using
 the gzip format.

 "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. The addition of
 "x" when writing will create the file exclusively, which fails if the file
 already exists. On systems that support it, the addition of "e" when
 reading or writing will set the flag to close the file on an execve() call.

 These functions, as well as gzip, will read and decode a sequence of gzip
 streams in a file. The append function of gzopen() can be used to create
 such a file. (Also see gzflush() for another way to do this.) When
 appending, gzopen does not test whether the file begins with a gzip stream,
 nor does it look for the end of the gzip streams to begin appending. gzopen
 will simply append a gzip stream to the existing file.

 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. When
 reading, this will be detected automatically by looking for the magic two-
 byte gzip header.

 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.
*/

 gzFile gzdopen (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. If you are using fileno() to get the
 file descriptor from a FILE *, then you will have to use dup() to avoid
 double-close()ing the file descriptor. Both gzclose() and fclose() will
 close the associated file descriptor, so they need to have different file
 descriptors.

 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).
*/

 int gzbuffer (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.
*/

 int gzsetparams (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.
*/

 int gzread (gzFile file, voidp buf, unsigned len);
/*
 Reads the given number of uncompressed bytes from the compressed file. If
 the input file is not in gzip format, gzread copies the given number of
 bytes into the buffer directly from the file.

 After reaching the end of a gzip stream in the input, gzread will continue
 to read, looking for another gzip stream. Any number of gzip streams may be
 concatenated in the input file, and will all be decompressed by gzread().
 If something other than a gzip stream is encountered after a gzip stream,
 that remaining trailing garbage is ignored (and no error is returned).

 gzread can be used to read a gzip file that is being concurrently written.
 Upon reaching the end of the input, gzread will return with the available
 data. If the error code returned by gzerror is Z_OK or Z_BUF_ERROR, then
 gzclearerr can be used to clear the end of file indicator in order to permit
 gzread to be tried again. Z_OK indicates that a gzip stream was completed
 on the last gzread. Z_BUF_ERROR indicates that the input file ended in the
 middle of a gzip stream. Note that gzread does not return -1 in the event
 of an incomplete gzip stream. This error is deferred until gzclose(), which
 will return Z_BUF_ERROR if the last gzread ended in the middle of a gzip
 stream. Alternatively, gzerror can be used before gzclose to detect this
 case.

 gzread returns the number of uncompressed bytes actually read, less than
 len for end of file, or -1 for error.
*/

 int gzwrite (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.
*/

 int gzprintf Z_ARG((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().
*/

 int gzputs (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.
*/

 char * gzgets (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.
*/

 int gzputc (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.
*/

 int gzgetc (gzFile file);
/*
 Reads one byte from the compressed file. gzgetc returns this byte or -1
 in case of end of file or error. This is implemented as a macro for speed.
 As such, it does not do all of the checking the other functions do. I.e.
 it does not check to see if file is NULL, nor whether the structure file
 points to has been clobbered or not.
*/

 int gzungetc (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().
*/

 int gzflush (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.
*/

/*
 z_off_t gzseek (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.
*/

 int gzrewind (gzFile file);
/*
 Rewinds the given file. This function is supported only for reading.

 gzrewind(file) is equivalent to (int)gzseek(file, 0L, SEEK_SET)
*/

/*
 z_off_t gztell (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)
*/

/*
 z_off_t gzoffset (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.
*/

 int gzeof (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.
*/

 int gzdirect (gzFile file);
/*
 Returns true (1) if file is being copied directly while reading, or false
 (0) if file is a gzip stream being decompressed.

 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().

 When writing, gzdirect() returns true (1) if transparent writing was
 requested ("wT" for the gzopen() mode), or false (0) otherwise. (Note:
 gzdirect() is not needed when writing. Transparent writing must be
 explicitly requested, so the application already knows the answer. When
 linking statically, using gzdirect() will include all of the zlib code for
 gzip file reading and decompression, which may not be desired.)
*/

 int gzclose (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, Z_MEM_ERROR if out of memory, Z_BUF_ERROR if the
 last read ended in the middle of a gzip stream, or Z_OK on success.
*/

 int gzclose_r (gzFile file);
 int gzclose_w (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.
*/

 const char * gzerror (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.
*/

 void gzclearerr (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.
*/

#endif /* !Z_SOLO */

 /* checksum functions */

/*
 These functions are not related to compression but are exported
 anyway because they might be useful in applications using the compression
 library.
*/

uint32_t adler32 (uint32_t adler, const uint8_t *buf, size_t 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();
*/

/*
 uLong adler32_combine (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. Note
 that the z_off_t type (like off_t) is a signed integer. If len2 is
 negative, the result has no meaning or utility.
*/

 uLong crc32 (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 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();
*/

/*
 uLong crc32_combine (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:
 */
 int deflateInit_ (z_streamp strm, int level,
 const char *version, int stream_size);
 int inflateInit_ (z_streamp strm,
 const char *version, int stream_size);
 int deflateInit2_ (z_streamp strm, int level, int method,
 int windowBits, int memLevel,
 int strategy, const char *version,
 int stream_size);
 int inflateInit2_ (z_streamp strm, int windowBits,
 const char *version, int stream_size);
 int inflateBackInit_ (z_streamp strm, int windowBits,
 unsigned char FAR *window,
 const char *version,
 int stream_size);
#define deflateInit(strm, level) \
 deflateInit_((strm), (level), ZLIB_VERSION, (int)sizeof(z_stream))
#define inflateInit(strm) \
 inflateInit_((strm), ZLIB_VERSION, (int)sizeof(z_stream))
#define deflateInit2(strm, level, method, windowBits, memLevel, strategy) \
 deflateInit2_((strm),(level),(method),(windowBits),(memLevel),\
 (strategy), ZLIB_VERSION, (int)sizeof(z_stream))
#define inflateInit2(strm, windowBits) \
 inflateInit2_((strm), (windowBits), ZLIB_VERSION, \
 (int)sizeof(z_stream))
#define inflateBackInit(strm, windowBits, window) \
 inflateBackInit_((strm), (windowBits), (window), \
 ZLIB_VERSION, (int)sizeof(z_stream))

#ifndef Z_SOLO

/* gzgetc() macro and its supporting function and exposed data structure. Note
 * that the real internal state is much larger than the exposed structure.
 * This abbreviated structure exposes just enough for the gzgetc() macro. The
 * user should not mess with these exposed elements, since their names or
 * behavior could change in the future, perhaps even capriciously. They can
 * only be used by the gzgetc() macro. You have been warned.
 */
 int gzgetc_ (gzFile file); /* backward compatibility */
#ifdef Z_PREFIX_SET
# undef z_gzgetc
# define z_gzgetc(g) \
 ((g)->have ? ((g)->have--, (g)->pos++, *((g)->next)++) : gzgetc(g))
#else
# define gzgetc(g) \
 ((g)->have ? ((g)->have--, (g)->pos++, *((g)->next)++) : gzgetc(g))
#endif

/* 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
 */
#ifdef Z_LARGE64
 gzFile gzopen64 (const char *, const char *);
 z_off64_t gzseek64 (gzFile, z_off64_t, int);
 z_off64_t gztell64 (gzFile);
 z_off64_t gzoffset64 (gzFile);
 uLong adler32_combine64 (uLong, uLong, z_off64_t);
 uLong crc32_combine64 (uLong, uLong, z_off64_t);
#endif

#if !defined(ZLIB_INTERNAL) && defined(Z_WANT64)
# ifdef Z_PREFIX_SET
# define z_gzopen z_gzopen64
# define z_gzseek z_gzseek64
# define z_gztell z_gztell64
# define z_gzoffset z_gzoffset64
# define z_adler32_combine z_adler32_combine64
# define z_crc32_combine z_crc32_combine64
# else
# define gzopen gzopen64
# define gzseek gzseek64
# define gztell gztell64
# define gzoffset gzoffset64
# define adler32_combine adler32_combine64
# define crc32_combine crc32_combine64
# endif
# ifndef Z_LARGE64
 gzFile gzopen64 (const char *, const char *);
 z_off_t gzseek64 (gzFile, z_off_t, int);
 z_off_t gztell64 (gzFile);
 z_off_t gzoffset64 (gzFile);
 uLong adler32_combine64 (uLong, uLong, z_off_t);
 uLong crc32_combine64 (uLong, uLong, z_off_t);
# endif
#else
 gzFile gzopen (const char *, const char *);
 z_off_t gzseek (gzFile, z_off_t, int);
 z_off_t gztell (gzFile);
 z_off_t gzoffset (gzFile);
 uLong adler32_combine (uLong, uLong, z_off_t);
 uLong crc32_combine (uLong, uLong, z_off_t);
#endif

#else /* Z_SOLO */

 uLong adler32_combine (uLong, uLong, z_off_t);
 uLong crc32_combine (uLong, uLong, z_off_t);

#endif /* !Z_SOLO */

/* hack for buggy compilers */
#if !defined(ZUTIL_H) && !defined(NO_DUMMY_DECL)
 struct internal_state {int dummy;};
#endif

/* undocumented functions */
 const char * zError (int);
 int inflateSyncPoint (z_streamp);

const uint32_t * get_crc_table(void);
 int inflateUndermine (z_streamp, int);
 int inflateResetKeep (z_streamp);
 int deflateResetKeep (z_streamp);
#if defined(_WIN32) && !defined(Z_SOLO)
 gzFile gzopen_w (const wchar_t *path,
 const char *mode);
#endif
#if defined(STDC) || defined(Z_HAVE_STDARG_H)
# ifndef Z_SOLO
 int gzvprintf Z_ARG((gzFile file,
 const char *format,
 va_list va));
# endif
#endif

#ifdef __cplusplus
}
#endif

#endif /* ZLIB_H */

#else
#include <zlib.h>
#endif

#endif