text: ﻿/* zlib.h -- interface of the 'zlib' general purpose compression library
    version 1.2.1, November 17th, 2003
  
    Copyright (C) 1995-2003 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 "1.2.1"
  #define ZLIB_VERNUM 0x1210
  
  /*
       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 (for example if an input file is mmap'ed), 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 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.
  
       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.
  
       This library does not provide any functions to write gzip files in memory.
    However such functions could be easily written using zlib's deflate function,
    the documentation in the gzip RFC, and the examples in gzio.c.
  
       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: ascii or binary */
      uLong   adler;      /* adler32 value of the uncompressed data */
      uLong   reserved;   /* reserved for future use */
  } z_stream;
  
  typedef z_stream FAR *z_streamp;
  
  /*
     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 /* will be removed, use Z_SYNC_FLUSH instead */
  #define Z_SYNC_FLUSH    2
  #define Z_FULL_FLUSH    3
  #define Z_FINISH        4
  #define Z_BLOCK         5
  /* 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_DEFAULT_STRATEGY    0
  /* compression strategy; see deflateInit2() below for details */
  
  #define Z_BINARY   0
  #define Z_ASCII    1
  #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,
     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.
  
      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.
  
      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
    the 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 data_type if it can make a good guess about
    the input data type (Z_ASCII or Z_BINARY). 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 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.  msg is set to null if there is no error
     message. inflateInit does not perform any decompression apart from reading
     the zlib header if present: this will be done by inflate().  (So next_in and
     avail_in may be modified, but next_out and avail_out are unchanged.)
  */
  
  
  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, or Z_BLOCK. 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 get 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.
  
      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 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() will decompress and check either zlib-wrapped or gzip-wrapped
    deflate data.  The header type is detected automatically.  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
    if next_in or next_out was 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).
  
       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 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.
  
        deflateInit2 returns Z_OK if success, Z_MEM_ERROR if there was not enough
     memory, Z_STREAM_ERROR if a parameter is invalid (such as an invalid
     method). 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 in
     deflate or deflate2. Thus the strings most likely to be useful should be
     put at the end of the dictionary, not at the front.
  
       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 (such as NULL dictionary) 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 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 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 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().  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 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 -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).
  
       inflateInit2 returns Z_OK if success, Z_MEM_ERROR if there was not enough
     memory, Z_STREAM_ERROR if a parameter is invalid (such as a negative
     memLevel). msg is set to null if there is no error message.  inflateInit2
     does not perform any decompression apart from reading the zlib header if
     present: this will be done by inflate(). (So next_in and avail_in may be
     modified, but next_out and avail_out are unchanged.)
  */
  
  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 this call returned Z_NEED_DICT. The dictionary chosen by the compressor
     can be determined from the adler32 value returned by this call of
     inflate. The compressor and decompressor must use exactly the same
     dictionary (see deflateSetDictionary).
  
       inflateSetDictionary returns Z_OK if success, Z_STREAM_ERROR if a
     parameter is invalid (such as NULL dictionary) 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 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 NULL).
  */
  
  /*
  ZEXTERN int ZEXPORT inflateBackInit OF((z_stream FAR *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_stream FAR *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 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_stream FAR *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 easily 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.
       This function can be used to compress a whole file at once if the
     input file is mmap'ed.
       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 compressed buffer.
       This function can be used to decompress a whole file at once if the
     input file is mmap'ed.
  
       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.
  */
  
  
  typedef voidp gzFile;
  
  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", or 'R' for run-length encoding
     as in "wb1R". (See the description of deflateInit2 for more information
     about the strategy parameter.)
  
       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 or if there was
     insufficient memory to allocate the (de)compression state; errno
     can be checked to distinguish the two cases (if errno is zero, the
     zlib error is Z_MEM_ERROR).  */
  
  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 (in 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 gzdopen(dup(fd), mode).
       gzdopen returns NULL if there was insufficient memory to allocate
     the (de)compression state.
  */
  
  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.
       gzread returns the number of uncompressed bytes actually read (0 for
     end of file, -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 actually written
     (0 in case of error).
  */
  
  ZEXTERN int ZEXPORTVA   gzprintf OF((gzFile file, const char *format, ...));
  /*
       Converts, formats, and writes the args to the compressed file under
     control of the format string, as in fprintf. gzprintf returns the number of
     uncompressed bytes actually written (0 in case of error).  The number of
     uncompressed bytes written is limited to 4095. The caller should assure that
     this limit is not exceeded. If it is exceeded, then gzprintf() will return
     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.
  */
  
  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.  The string is then terminated with a null
     character.
        gzgets returns buf, or Z_NULL in case of error.
  */
  
  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 again later.
     Only one character of push-back is allowed.  gzungetc() returns the
     character pushed, or -1 on failure.  gzungetc() will fail if a
     character has been pushed but not read yet, or if c is -1. 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 returns Z_OK if
     the flush parameter is Z_FINISH and all output could be flushed.
       gzflush should be called only when strictly necessary because it can
     degrade compression.
  */
  
  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.
  
     gztell(file) is equivalent to gzseek(file, 0L, SEEK_CUR)
  */
  
  ZEXTERN int ZEXPORT gzeof OF((gzFile file));
  /*
       Returns 1 when EOF has previously been detected reading the given
     input stream, otherwise zero.
  */
  
  ZEXTERN int ZEXPORT    gzclose OF((gzFile file));
  /*
       Flushes all pending output if necessary, closes the compressed file
     and deallocates all the (de)compression state. The return value is the zlib
     error number (see function gzerror below).
  */
  
  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.
  */
  
  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 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 crc32   OF((uLong crc, const Bytef *buf, uInt len));
  /*
       Update a running crc with the bytes buf[0..len-1] and return the updated
     crc. If buf is 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();
  */
  
  
                          /* 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_stream FAR *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))
  
  
  #if !defined(ZUTIL_H) && !defined(NO_DUMMY_DECL)
      struct internal_state {int dummy;}; /* hack for buggy compilers */
  #endif
  
  ZEXTERN const char   * ZEXPORT zError           OF((int err));
  ZEXTERN int            ZEXPORT inflateSyncPoint OF((z_streamp z));
  ZEXTERN const uLongf * ZEXPORT get_crc_table    OF((void));
  
  #ifdef __cplusplus
  }
  #endif
  
  #endif /* ZLIB_H */
  