zlib.h

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   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.