hedgewars: comparison misc/winutils/include/zlib.h

equal deleted inserted replaced

-:49ab679cb384
+:00696c1450da
+/* zlib.h -- interface of the 'zlib' general purpose compression library
+version 1.2.5, April 19th, 2010
+Copyright (C) 1995-2010 Jean-loup Gailly and Mark Adler
+This software is provided 'as-is', without any express or implied
+warranty.  In no event will the authors be held liable for any damages
+arising from the use of this software.
+Permission is granted to anyone to use this software for any purpose,
+including commercial applications, and to alter it and redistribute it
+freely, subject to the following restrictions:
+1. The origin of this software must not be misrepresented; you must not
+claim that you wrote the original software. If you use this software
+in a product, an acknowledgment in the product documentation would be
+appreciated but is not required.
+2. Altered source versions must be plainly marked as such, and must not be
+misrepresented as being the original software.
+3. This notice may not be removed or altered from any source distribution.
+Jean-loup Gailly        Mark Adler
+jloup@gzip.org          madler@alumni.caltech.edu
+The data format used by the zlib library is described by RFCs (Request for
+Comments) 1950 to 1952 in the files http://www.ietf.org/rfc/rfc1950.txt
+(zlib format), rfc1951.txt (deflate format) and rfc1952.txt (gzip format).
+*/
+#ifndef ZLIB_H
+#define ZLIB_H
+#include "zconf.h"
+#ifdef __cplusplus
+extern "C" {
+#endif
+#define ZLIB_VERSION "1.2.5"
+#define ZLIB_VERNUM 0x1250
+#define ZLIB_VER_MAJOR 1
+#define ZLIB_VER_MINOR 2
+#define ZLIB_VER_REVISION 5
+#define ZLIB_VER_SUBREVISION 0
+/*
+The 'zlib' compression library provides in-memory compression and
+decompression functions, including integrity checks of the uncompressed data.
+This version of the library supports only one compression method (deflation)
+but other algorithms will be added later and will have the same stream
+interface.
+Compression can be done in a single step if the buffers are large enough,
+or can be done by repeated calls of the compression function.  In the latter
+case, the application must provide more input and/or consume the output
+(providing more output space) before each call.
+The compressed data format used by default by the in-memory functions is
+the zlib format, which is a zlib wrapper documented in RFC 1950, wrapped
+around a deflate stream, which is itself documented in RFC 1951.
+The library also supports reading and writing files in gzip (.gz) format
+with an interface similar to that of stdio using the functions that start
+with "gz".  The gzip format is different from the zlib format.  gzip is a
+gzip wrapper, documented in RFC 1952, wrapped around a deflate stream.
+This library can optionally read and write gzip streams in memory as well.
+The zlib format was designed to be compact and fast for use in memory
+and on communications channels.  The gzip format was designed for single-
+file compression on file systems, has a larger header than zlib to maintain
+directory information, and uses a different, slower check method than zlib.
+The library does not install any signal handler.  The decoder checks
+the consistency of the compressed data, so the library should never crash
+even in case of corrupted input.
+*/
+typedef voidpf (*alloc_func) OF((voidpf opaque, uInt items, uInt size));
+typedef void   (*free_func)  OF((voidpf opaque, voidpf address));
+struct internal_state;
+typedef struct z_stream_s {
+Bytef    *next_in;  /* next input byte */
+uInt     avail_in;  /* number of bytes available at next_in */
+uLong    total_in;  /* total nb of input bytes read so far */
+Bytef    *next_out; /* next output byte should be put there */
+uInt     avail_out; /* remaining free space at next_out */
+uLong    total_out; /* total nb of bytes output so far */
+char     *msg;      /* last error message, NULL if no error */
+struct internal_state FAR *state; /* not visible by applications */
+alloc_func zalloc;  /* used to allocate the internal state */
+free_func  zfree;   /* used to free the internal state */
+voidpf     opaque;  /* private data object passed to zalloc and zfree */
+int     data_type;  /* best guess about the data type: binary or text */
+uLong   adler;      /* adler32 value of the uncompressed data */
+uLong   reserved;   /* reserved for future use */
+} z_stream;
+typedef z_stream FAR *z_streamp;
+/*
+gzip header information passed to and from zlib routines.  See RFC 1952
+for more details on the meanings of these fields.
+*/
+typedef struct gz_header_s {
+int     text;       /* true if compressed data believed to be text */
+uLong   time;       /* modification time */
+int     xflags;     /* extra flags (not used when writing a gzip file) */
+int     os;         /* operating system */
+Bytef   *extra;     /* pointer to extra field or Z_NULL if none */
+uInt    extra_len;  /* extra field length (valid if extra != Z_NULL) */
+uInt    extra_max;  /* space at extra (only when reading header) */
+Bytef   *name;      /* pointer to zero-terminated file name or Z_NULL */
+uInt    name_max;   /* space at name (only when reading header) */
+Bytef   *comment;   /* pointer to zero-terminated comment or Z_NULL */
+uInt    comm_max;   /* space at comment (only when reading header) */
+int     hcrc;       /* true if there was or will be a header crc */
+int     done;       /* true when done reading gzip header (not used
+when writing a gzip file) */
+} gz_header;
+typedef gz_header FAR *gz_headerp;
+/*
+The application must update next_in and avail_in when avail_in has dropped
+to zero.  It must update next_out and avail_out when avail_out has dropped
+to zero.  The application must initialize zalloc, zfree and opaque before
+calling the init function.  All other fields are set by the compression
+library and must not be updated by the application.
+The opaque value provided by the application will be passed as the first
+parameter for calls of zalloc and zfree.  This can be useful for custom
+memory management.  The compression library attaches no meaning to the
+opaque value.
+zalloc must return Z_NULL if there is not enough memory for the object.
+If zlib is used in a multi-threaded application, zalloc and zfree must be
+thread safe.
+On 16-bit systems, the functions zalloc and zfree must be able to allocate
+exactly 65536 bytes, but will not be required to allocate more than this if
+the symbol MAXSEG_64K is defined (see zconf.h).  WARNING: On MSDOS, pointers
+returned by zalloc for objects of exactly 65536 bytes *must* have their
+offset normalized to zero.  The default allocation function provided by this
+library ensures this (see zutil.c).  To reduce memory requirements and avoid
+any allocation of 64K objects, at the expense of compression ratio, compile
+the library with -DMAX_WBITS=14 (see zconf.h).
+The fields total_in and total_out can be used for statistics or progress
+reports.  After compression, total_in holds the total size of the
+uncompressed data and may be saved for use in the decompressor (particularly
+if the decompressor wants to decompress everything in a single step).
+*/
+/* constants */
+#define Z_NO_FLUSH      0
+#define Z_PARTIAL_FLUSH 1
+#define Z_SYNC_FLUSH    2
+#define Z_FULL_FLUSH    3
+#define Z_FINISH        4
+#define Z_BLOCK         5
+#define Z_TREES         6
+/* Allowed flush values; see deflate() and inflate() below for details */
+#define Z_OK            0
+#define Z_STREAM_END    1
+#define Z_NEED_DICT     2
+#define Z_ERRNO        (-1)
+#define Z_STREAM_ERROR (-2)
+#define Z_DATA_ERROR   (-3)
+#define Z_MEM_ERROR    (-4)
+#define Z_BUF_ERROR    (-5)
+#define Z_VERSION_ERROR (-6)
+/* Return codes for the compression/decompression functions. Negative values
+* are errors, positive values are used for special but normal events.
+*/
+#define Z_NO_COMPRESSION         0
+#define Z_BEST_SPEED             1
+#define Z_BEST_COMPRESSION       9
+#define Z_DEFAULT_COMPRESSION  (-1)
+/* compression levels */
+#define Z_FILTERED            1
+#define Z_HUFFMAN_ONLY        2
+#define Z_RLE                 3
+#define Z_FIXED               4
+#define Z_DEFAULT_STRATEGY    0
+/* compression strategy; see deflateInit2() below for details */
+#define Z_BINARY   0
+#define Z_TEXT     1
+#define Z_ASCII    Z_TEXT   /* for compatibility with 1.2.2 and earlier */
+#define Z_UNKNOWN  2
+/* Possible values of the data_type field (though see inflate()) */
+#define Z_DEFLATED   8
+/* The deflate compression method (the only one supported in this version) */
+#define Z_NULL  0  /* for initializing zalloc, zfree, opaque */
+#define zlib_version zlibVersion()
+/* for compatibility with versions < 1.0.2 */
+/* basic functions */
+ZEXTERN const char * ZEXPORT zlibVersion OF((void));
+/* The application can compare zlibVersion and ZLIB_VERSION for consistency.
+If the first character differs, the library code actually used is not
+compatible with the zlib.h header file used by the application.  This check
+is automatically made by deflateInit and inflateInit.
+*/
+/*
+ZEXTERN int ZEXPORT deflateInit OF((z_streamp strm, int level));
+Initializes the internal stream state for compression.  The fields
+zalloc, zfree and opaque must be initialized before by the caller.  If
+zalloc and zfree are set to Z_NULL, deflateInit updates them to use default
+allocation functions.
+The compression level must be Z_DEFAULT_COMPRESSION, or between 0 and 9:
+1 gives best speed, 9 gives best compression, 0 gives no compression at all
+(the input data is simply copied a block at a time).  Z_DEFAULT_COMPRESSION
+requests a default compromise between speed and compression (currently
+equivalent to level 6).
+deflateInit returns Z_OK if success, Z_MEM_ERROR if there was not enough
+memory, Z_STREAM_ERROR if level is not a valid compression level, or
+Z_VERSION_ERROR if the zlib library version (zlib_version) is incompatible
+with the version assumed by the caller (ZLIB_VERSION).  msg is set to null
+if there is no error message.  deflateInit does not perform any compression:
+this will be done by deflate().
+*/
+ZEXTERN int ZEXPORT deflate OF((z_streamp strm, int flush));
+/*
+deflate compresses as much data as possible, and stops when the input
+buffer becomes empty or the output buffer becomes full.  It may introduce
+some output latency (reading input without producing any output) except when
+forced to flush.
+The detailed semantics are as follows.  deflate performs one or both of the
+following actions:
+- Compress more input starting at next_in and update next_in and avail_in
+accordingly.  If not all input can be processed (because there is not
+enough room in the output buffer), next_in and avail_in are updated and
+processing will resume at this point for the next call of deflate().
+- Provide more output starting at next_out and update next_out and avail_out
+accordingly.  This action is forced if the parameter flush is non zero.
+Forcing flush frequently degrades the compression ratio, so this parameter
+should be set only when necessary (in interactive applications).  Some
+output may be provided even if flush is not set.
+Before the call of deflate(), the application should ensure that at least
+one of the actions is possible, by providing more input and/or consuming more
+output, and updating avail_in or avail_out accordingly; avail_out should
+never be zero before the call.  The application can consume the compressed
+output when it wants, for example when the output buffer is full (avail_out
+== 0), or after each call of deflate().  If deflate returns Z_OK and with
+zero avail_out, it must be called again after making room in the output
+buffer because there might be more output pending.
+Normally the parameter flush is set to Z_NO_FLUSH, which allows deflate to
+decide how much data to accumulate before producing output, in order to
+maximize compression.
+If the parameter flush is set to Z_SYNC_FLUSH, all pending output is
+flushed to the output buffer and the output is aligned on a byte boundary, so
+that the decompressor can get all input data available so far.  (In
+particular avail_in is zero after the call if enough output space has been
+provided before the call.) Flushing may degrade compression for some
+compression algorithms and so it should be used only when necessary.  This
+completes the current deflate block and follows it with an empty stored block
+that is three bits plus filler bits to the next byte, followed by four bytes
+(00 00 ff ff).
+If flush is set to Z_PARTIAL_FLUSH, all pending output is flushed to the
+output buffer, but the output is not aligned to a byte boundary.  All of the
+input data so far will be available to the decompressor, as for Z_SYNC_FLUSH.
+This completes the current deflate block and follows it with an empty fixed
+codes block that is 10 bits long.  This assures that enough bytes are output
+in order for the decompressor to finish the block before the empty fixed code
+block.
+If flush is set to Z_BLOCK, a deflate block is completed and emitted, as
+for Z_SYNC_FLUSH, but the output is not aligned on a byte boundary, and up to
+seven bits of the current block are held to be written as the next byte after
+the next deflate block is completed.  In this case, the decompressor may not
+be provided enough bits at this point in order to complete decompression of
+the data provided so far to the compressor.  It may need to wait for the next
+block to be emitted.  This is for advanced applications that need to control
+the emission of deflate blocks.
+If flush is set to Z_FULL_FLUSH, all output is flushed as with
+Z_SYNC_FLUSH, and the compression state is reset so that decompression can
+restart from this point if previous compressed data has been damaged or if
+random access is desired.  Using Z_FULL_FLUSH too often can seriously degrade
+compression.
+If deflate returns with avail_out == 0, this function must be called again
+with the same value of the flush parameter and more output space (updated
+avail_out), until the flush is complete (deflate returns with non-zero
+avail_out).  In the case of a Z_FULL_FLUSH or Z_SYNC_FLUSH, make sure that
+avail_out is greater than six to avoid repeated flush markers due to
+avail_out == 0 on return.
+If the parameter flush is set to Z_FINISH, pending input is processed,
+pending output is flushed and deflate returns with Z_STREAM_END if there was
+enough output space; if deflate returns with Z_OK, this function must be
+called again with Z_FINISH and more output space (updated avail_out) but no
+more input data, until it returns with Z_STREAM_END or an error.  After
+deflate has returned Z_STREAM_END, the only possible operations on the stream
+are deflateReset or deflateEnd.
+Z_FINISH can be used immediately after deflateInit if all the compression
+is to be done in a single step.  In this case, avail_out must be at least the
+value returned by deflateBound (see below).  If deflate does not return
+Z_STREAM_END, then it must be called again as described above.
+deflate() sets strm->adler to the adler32 checksum of all input read
+so far (that is, total_in bytes).
+deflate() may update strm->data_type if it can make a good guess about
+the input data type (Z_BINARY or Z_TEXT).  In doubt, the data is considered
+binary.  This field is only for information purposes and does not affect the
+compression algorithm in any manner.
+deflate() returns Z_OK if some progress has been made (more input
+processed or more output produced), Z_STREAM_END if all input has been
+consumed and all output has been produced (only when flush is set to
+Z_FINISH), Z_STREAM_ERROR if the stream state was inconsistent (for example
+if next_in or next_out was Z_NULL), Z_BUF_ERROR if no progress is possible
+(for example avail_in or avail_out was zero).  Note that Z_BUF_ERROR is not
+fatal, and deflate() can be called again with more input and more output
+space to continue compressing.
+*/
+ZEXTERN int ZEXPORT deflateEnd OF((z_streamp strm));
+/*
+All dynamically allocated data structures for this stream are freed.
+This function discards any unprocessed input and does not flush any pending
+output.
+deflateEnd returns Z_OK if success, Z_STREAM_ERROR if the
+stream state was inconsistent, Z_DATA_ERROR if the stream was freed
+prematurely (some input or output was discarded).  In the error case, msg
+may be set but then points to a static string (which must not be
+deallocated).
+*/
+/*
+ZEXTERN int ZEXPORT inflateInit OF((z_streamp strm));
+Initializes the internal stream state for decompression.  The fields
+next_in, avail_in, zalloc, zfree and opaque must be initialized before by
+the caller.  If next_in is not Z_NULL and avail_in is large enough (the
+exact value depends on the compression method), inflateInit determines the
+compression method from the zlib header and allocates all data structures
+accordingly; otherwise the allocation will be deferred to the first call of
+inflate.  If zalloc and zfree are set to Z_NULL, inflateInit updates them to
+use default allocation functions.
+inflateInit returns Z_OK if success, Z_MEM_ERROR if there was not enough
+memory, Z_VERSION_ERROR if the zlib library version is incompatible with the
+version assumed by the caller, or Z_STREAM_ERROR if the parameters are
+invalid, such as a null pointer to the structure.  msg is set to null if
+there is no error message.  inflateInit does not perform any decompression
+apart from possibly reading the zlib header if present: actual decompression
+will be done by inflate().  (So next_in and avail_in may be modified, but
+next_out and avail_out are unused and unchanged.) The current implementation
+of inflateInit() does not process any header information -- that is deferred
+until inflate() is called.
+*/
+ZEXTERN int ZEXPORT inflate OF((z_streamp strm, int flush));
+/*
+inflate decompresses as much data as possible, and stops when the input
+buffer becomes empty or the output buffer becomes full.  It may introduce
+some output latency (reading input without producing any output) except when
+forced to flush.
+The detailed semantics are as follows.  inflate performs one or both of the
+following actions:
+- Decompress more input starting at next_in and update next_in and avail_in
+accordingly.  If not all input can be processed (because there is not
+enough room in the output buffer), next_in is updated and processing will
+resume at this point for the next call of inflate().
+- Provide more output starting at next_out and update next_out and avail_out
+accordingly.  inflate() provides as much output as possible, until there is
+no more input data or no more space in the output buffer (see below about
+the flush parameter).
+Before the call of inflate(), the application should ensure that at least
+one of the actions is possible, by providing more input and/or consuming more
+output, and updating the next_* and avail_* values accordingly.  The
+application can consume the uncompressed output when it wants, for example
+when the output buffer is full (avail_out == 0), or after each call of
+inflate().  If inflate returns Z_OK and with zero avail_out, it must be
+called again after making room in the output buffer because there might be
+more output pending.
+The flush parameter of inflate() can be Z_NO_FLUSH, Z_SYNC_FLUSH, Z_FINISH,
+Z_BLOCK, or Z_TREES.  Z_SYNC_FLUSH requests that inflate() flush as much
+output as possible to the output buffer.  Z_BLOCK requests that inflate()
+stop if and when it gets to the next deflate block boundary.  When decoding
+the zlib or gzip format, this will cause inflate() to return immediately
+after the header and before the first block.  When doing a raw inflate,
+inflate() will go ahead and process the first block, and will return when it
+gets to the end of that block, or when it runs out of data.
+The Z_BLOCK option assists in appending to or combining deflate streams.
+Also to assist in this, on return inflate() will set strm->data_type to the
+number of unused bits in the last byte taken from strm->next_in, plus 64 if
+inflate() is currently decoding the last block in the deflate stream, plus
+128 if inflate() returned immediately after decoding an end-of-block code or
+decoding the complete header up to just before the first byte of the deflate
+stream.  The end-of-block will not be indicated until all of the uncompressed
+data from that block has been written to strm->next_out.  The number of
+unused bits may in general be greater than seven, except when bit 7 of
+data_type is set, in which case the number of unused bits will be less than
+eight.  data_type is set as noted here every time inflate() returns for all
+flush options, and so can be used to determine the amount of currently
+consumed input in bits.
+The Z_TREES option behaves as Z_BLOCK does, but it also returns when the
+end of each deflate block header is reached, before any actual data in that
+block is decoded.  This allows the caller to determine the length of the
+deflate block header for later use in random access within a deflate block.
+256 is added to the value of strm->data_type when inflate() returns
+immediately after reaching the end of the deflate block header.
+inflate() should normally be called until it returns Z_STREAM_END or an
+error.  However if all decompression is to be performed in a single step (a
+single call of inflate), the parameter flush should be set to Z_FINISH.  In
+this case all pending input is processed and all pending output is flushed;
+avail_out must be large enough to hold all the uncompressed data.  (The size
+of the uncompressed data may have been saved by the compressor for this
+purpose.) The next operation on this stream must be inflateEnd to deallocate
+the decompression state.  The use of Z_FINISH is never required, but can be
+used to inform inflate that a faster approach may be used for the single
+inflate() call.
+In this implementation, inflate() always flushes as much output as
+possible to the output buffer, and always uses the faster approach on the
+first call.  So the only effect of the flush parameter in this implementation
+is on the return value of inflate(), as noted below, or when it returns early
+because Z_BLOCK or Z_TREES is used.
+If a preset dictionary is needed after this call (see inflateSetDictionary
+below), inflate sets strm->adler to the adler32 checksum of the dictionary
+chosen by the compressor and returns Z_NEED_DICT; otherwise it sets
+strm->adler to the adler32 checksum of all output produced so far (that is,
+total_out bytes) and returns Z_OK, Z_STREAM_END or an error code as described
+below.  At the end of the stream, inflate() checks that its computed adler32
+checksum is equal to that saved by the compressor and returns Z_STREAM_END
+only if the checksum is correct.
+inflate() can decompress and check either zlib-wrapped or gzip-wrapped
+deflate data.  The header type is detected automatically, if requested when
+initializing with inflateInit2().  Any information contained in the gzip
+header is not retained, so applications that need that information should
+instead use raw inflate, see inflateInit2() below, or inflateBack() and
+perform their own processing of the gzip header and trailer.
+inflate() returns Z_OK if some progress has been made (more input processed
+or more output produced), Z_STREAM_END if the end of the compressed data has
+been reached and all uncompressed output has been produced, Z_NEED_DICT if a
+preset dictionary is needed at this point, Z_DATA_ERROR if the input data was
+corrupted (input stream not conforming to the zlib format or incorrect check
+value), Z_STREAM_ERROR if the stream structure was inconsistent (for example
+next_in or next_out was Z_NULL), Z_MEM_ERROR if there was not enough memory,
+Z_BUF_ERROR if no progress is possible or if there was not enough room in the
+output buffer when Z_FINISH is used.  Note that Z_BUF_ERROR is not fatal, and
+inflate() can be called again with more input and more output space to
+continue decompressing.  If Z_DATA_ERROR is returned, the application may
+then call inflateSync() to look for a good compression block if a partial
+recovery of the data is desired.
+*/
+ZEXTERN int ZEXPORT inflateEnd OF((z_streamp strm));
+/*
+All dynamically allocated data structures for this stream are freed.
+This function discards any unprocessed input and does not flush any pending
+output.
+inflateEnd returns Z_OK if success, Z_STREAM_ERROR if the stream state
+was inconsistent.  In the error case, msg may be set but then points to a
+static string (which must not be deallocated).
+*/
+/* Advanced functions */
+/*
+The following functions are needed only in some special applications.
+*/
+/*
+ZEXTERN int ZEXPORT deflateInit2 OF((z_streamp strm,
+int  level,
+int  method,
+int  windowBits,
+int  memLevel,
+int  strategy));
+This is another version of deflateInit with more compression options.  The
+fields next_in, zalloc, zfree and opaque must be initialized before by the
+caller.
+The method parameter is the compression method.  It must be Z_DEFLATED in
+this version of the library.
+The windowBits parameter is the base two logarithm of the window size
+(the size of the history buffer).  It should be in the range 8..15 for this
+version of the library.  Larger values of this parameter result in better
+compression at the expense of memory usage.  The default value is 15 if
+deflateInit is used instead.
+windowBits can also be -8..-15 for raw deflate.  In this case, -windowBits
+determines the window size.  deflate() will then generate raw deflate data
+with no zlib header or trailer, and will not compute an adler32 check value.
+windowBits can also be greater than 15 for optional gzip encoding.  Add
+16 to windowBits to write a simple gzip header and trailer around the
+compressed data instead of a zlib wrapper.  The gzip header will have no
+file name, no extra data, no comment, no modification time (set to zero), no
+header crc, and the operating system will be set to 255 (unknown).  If a
+gzip stream is being written, strm->adler is a crc32 instead of an adler32.
+The memLevel parameter specifies how much memory should be allocated
+for the internal compression state.  memLevel=1 uses minimum memory but is
+slow and reduces compression ratio; memLevel=9 uses maximum memory for
+optimal speed.  The default value is 8.  See zconf.h for total memory usage
+as a function of windowBits and memLevel.
+The strategy parameter is used to tune the compression algorithm.  Use the
+value Z_DEFAULT_STRATEGY for normal data, Z_FILTERED for data produced by a
+filter (or predictor), Z_HUFFMAN_ONLY to force Huffman encoding only (no
+string match), or Z_RLE to limit match distances to one (run-length
+encoding).  Filtered data consists mostly of small values with a somewhat
+random distribution.  In this case, the compression algorithm is tuned to
+compress them better.  The effect of Z_FILTERED is to force more Huffman
+coding and less string matching; it is somewhat intermediate between
+Z_DEFAULT_STRATEGY and Z_HUFFMAN_ONLY.  Z_RLE is designed to be almost as
+fast as Z_HUFFMAN_ONLY, but give better compression for PNG image data.  The
+strategy parameter only affects the compression ratio but not the
+correctness of the compressed output even if it is not set appropriately.
+Z_FIXED prevents the use of dynamic Huffman codes, allowing for a simpler
+decoder for special applications.
+deflateInit2 returns Z_OK if success, Z_MEM_ERROR if there was not enough
+memory, Z_STREAM_ERROR if any parameter is invalid (such as an invalid
+method), or Z_VERSION_ERROR if the zlib library version (zlib_version) is
+incompatible with the version assumed by the caller (ZLIB_VERSION).  msg is
+set to null if there is no error message.  deflateInit2 does not perform any
+compression: this will be done by deflate().
+*/
+ZEXTERN int ZEXPORT deflateSetDictionary OF((z_streamp strm,
+const Bytef *dictionary,
+uInt  dictLength));
+/*
+Initializes the compression dictionary from the given byte sequence
+without producing any compressed output.  This function must be called
+immediately after deflateInit, deflateInit2 or deflateReset, before any call
+of deflate.  The compressor and decompressor must use exactly the same
+dictionary (see inflateSetDictionary).
+The dictionary should consist of strings (byte sequences) that are likely
+to be encountered later in the data to be compressed, with the most commonly
+used strings preferably put towards the end of the dictionary.  Using a
+dictionary is most useful when the data to be compressed is short and can be
+predicted with good accuracy; the data can then be compressed better than
+with the default empty dictionary.
+Depending on the size of the compression data structures selected by
+deflateInit or deflateInit2, a part of the dictionary may in effect be
+discarded, for example if the dictionary is larger than the window size
+provided in deflateInit or deflateInit2.  Thus the strings most likely to be
+useful should be put at the end of the dictionary, not at the front.  In
+addition, the current implementation of deflate will use at most the window
+size minus 262 bytes of the provided dictionary.
+Upon return of this function, strm->adler is set to the adler32 value
+of the dictionary; the decompressor may later use this value to determine
+which dictionary has been used by the compressor.  (The adler32 value
+applies to the whole dictionary even if only a subset of the dictionary is
+actually used by the compressor.) If a raw deflate was requested, then the
+adler32 value is not computed and strm->adler is not set.
+deflateSetDictionary returns Z_OK if success, or Z_STREAM_ERROR if a
+parameter is invalid (e.g.  dictionary being Z_NULL) or the stream state is
+inconsistent (for example if deflate has already been called for this stream
+or if the compression method is bsort).  deflateSetDictionary does not
+perform any compression: this will be done by deflate().
+*/
+ZEXTERN int ZEXPORT deflateCopy OF((z_streamp dest,
+z_streamp source));
+/*
+Sets the destination stream as a complete copy of the source stream.
+This function can be useful when several compression strategies will be
+tried, for example when there are several ways of pre-processing the input
+data with a filter.  The streams that will be discarded should then be freed
+by calling deflateEnd.  Note that deflateCopy duplicates the internal
+compression state which can be quite large, so this strategy is slow and can
+consume lots of memory.
+deflateCopy returns Z_OK if success, Z_MEM_ERROR if there was not
+enough memory, Z_STREAM_ERROR if the source stream state was inconsistent
+(such as zalloc being Z_NULL).  msg is left unchanged in both source and
+destination.
+*/
+ZEXTERN int ZEXPORT deflateReset OF((z_streamp strm));
+/*
+This function is equivalent to deflateEnd followed by deflateInit,
+but does not free and reallocate all the internal compression state.  The
+stream will keep the same compression level and any other attributes that
+may have been set by deflateInit2.
+deflateReset returns Z_OK if success, or Z_STREAM_ERROR if the source
+stream state was inconsistent (such as zalloc or state being Z_NULL).
+*/
+ZEXTERN int ZEXPORT deflateParams OF((z_streamp strm,
+int level,
+int strategy));
+/*
+Dynamically update the compression level and compression strategy.  The
+interpretation of level and strategy is as in deflateInit2.  This can be
+used to switch between compression and straight copy of the input data, or
+to switch to a different kind of input data requiring a different strategy.
+If the compression level is changed, the input available so far is
+compressed with the old level (and may be flushed); the new level will take
+effect only at the next call of deflate().
+Before the call of deflateParams, the stream state must be set as for
+a call of deflate(), since the currently available input may have to be
+compressed and flushed.  In particular, strm->avail_out must be non-zero.
+deflateParams returns Z_OK if success, Z_STREAM_ERROR if the source
+stream state was inconsistent or if a parameter was invalid, Z_BUF_ERROR if
+strm->avail_out was zero.
+*/
+ZEXTERN int ZEXPORT deflateTune OF((z_streamp strm,
+int good_length,
+int max_lazy,
+int nice_length,
+int max_chain));
+/*
+Fine tune deflate's internal compression parameters.  This should only be
+used by someone who understands the algorithm used by zlib's deflate for
+searching for the best matching string, and even then only by the most
+fanatic optimizer trying to squeeze out the last compressed bit for their
+specific input data.  Read the deflate.c source code for the meaning of the
+max_lazy, good_length, nice_length, and max_chain parameters.
+deflateTune() can be called after deflateInit() or deflateInit2(), and
+returns Z_OK on success, or Z_STREAM_ERROR for an invalid deflate stream.
+*/
+ZEXTERN uLong ZEXPORT deflateBound OF((z_streamp strm,
+uLong sourceLen));
+/*
+deflateBound() returns an upper bound on the compressed size after
+deflation of sourceLen bytes.  It must be called after deflateInit() or
+deflateInit2(), and after deflateSetHeader(), if used.  This would be used
+to allocate an output buffer for deflation in a single pass, and so would be
+called before deflate().
+*/
+ZEXTERN int ZEXPORT deflatePrime OF((z_streamp strm,
+int bits,
+int value));
+/*
+deflatePrime() inserts bits in the deflate output stream.  The intent
+is that this function is used to start off the deflate output with the bits
+leftover from a previous deflate stream when appending to it.  As such, this
+function can only be used for raw deflate, and must be used before the first
+deflate() call after a deflateInit2() or deflateReset().  bits must be less
+than or equal to 16, and that many of the least significant bits of value
+will be inserted in the output.
+deflatePrime returns Z_OK if success, or Z_STREAM_ERROR if the source
+stream state was inconsistent.
+*/
+ZEXTERN int ZEXPORT deflateSetHeader OF((z_streamp strm,
+gz_headerp head));
+/*
+deflateSetHeader() provides gzip header information for when a gzip
+stream is requested by deflateInit2().  deflateSetHeader() may be called
+after deflateInit2() or deflateReset() and before the first call of
+deflate().  The text, time, os, extra field, name, and comment information
+in the provided gz_header structure are written to the gzip header (xflag is
+ignored -- the extra flags are set according to the compression level).  The
+caller must assure that, if not Z_NULL, name and comment are terminated with
+a zero byte, and that if extra is not Z_NULL, that extra_len bytes are
+available there.  If hcrc is true, a gzip header crc is included.  Note that
+the current versions of the command-line version of gzip (up through version
+1.3.x) do not support header crc's, and will report that it is a "multi-part
+gzip file" and give up.
+If deflateSetHeader is not used, the default gzip header has text false,
+the time set to zero, and os set to 255, with no extra, name, or comment
+fields.  The gzip header is returned to the default state by deflateReset().
+deflateSetHeader returns Z_OK if success, or Z_STREAM_ERROR if the source
+stream state was inconsistent.
+*/
+/*
+ZEXTERN int ZEXPORT inflateInit2 OF((z_streamp strm,
+int  windowBits));
+This is another version of inflateInit with an extra parameter.  The
+fields next_in, avail_in, zalloc, zfree and opaque must be initialized
+before by the caller.
+The windowBits parameter is the base two logarithm of the maximum window
+size (the size of the history buffer).  It should be in the range 8..15 for
+this version of the library.  The default value is 15 if inflateInit is used
+instead.  windowBits must be greater than or equal to the windowBits value
+provided to deflateInit2() while compressing, or it must be equal to 15 if
+deflateInit2() was not used.  If a compressed stream with a larger window
+size is given as input, inflate() will return with the error code
+Z_DATA_ERROR instead of trying to allocate a larger window.
+windowBits can also be zero to request that inflate use the window size in
+the zlib header of the compressed stream.
+windowBits can also be -8..-15 for raw inflate.  In this case, -windowBits
+determines the window size.  inflate() will then process raw deflate data,
+not looking for a zlib or gzip header, not generating a check value, and not
+looking for any check values for comparison at the end of the stream.  This
+is for use with other formats that use the deflate compressed data format
+such as zip.  Those formats provide their own check values.  If a custom
+format is developed using the raw deflate format for compressed data, it is
+recommended that a check value such as an adler32 or a crc32 be applied to
+the uncompressed data as is done in the zlib, gzip, and zip formats.  For
+most applications, the zlib format should be used as is.  Note that comments
+above on the use in deflateInit2() applies to the magnitude of windowBits.
+windowBits can also be greater than 15 for optional gzip decoding.  Add
+32 to windowBits to enable zlib and gzip decoding with automatic header
+detection, or add 16 to decode only the gzip format (the zlib format will
+return a Z_DATA_ERROR).  If a gzip stream is being decoded, strm->adler is a
+crc32 instead of an adler32.
+inflateInit2 returns Z_OK if success, Z_MEM_ERROR if there was not enough
+memory, Z_VERSION_ERROR if the zlib library version is incompatible with the
+version assumed by the caller, or Z_STREAM_ERROR if the parameters are
+invalid, such as a null pointer to the structure.  msg is set to null if
+there is no error message.  inflateInit2 does not perform any decompression
+apart from possibly reading the zlib header if present: actual decompression
+will be done by inflate().  (So next_in and avail_in may be modified, but
+next_out and avail_out are unused and unchanged.) The current implementation
+of inflateInit2() does not process any header information -- that is
+deferred until inflate() is called.
+*/
+ZEXTERN int ZEXPORT inflateSetDictionary OF((z_streamp strm,
+const Bytef *dictionary,
+uInt  dictLength));
+/*
+Initializes the decompression dictionary from the given uncompressed byte
+sequence.  This function must be called immediately after a call of inflate,
+if that call returned Z_NEED_DICT.  The dictionary chosen by the compressor
+can be determined from the adler32 value returned by that call of inflate.
+The compressor and decompressor must use exactly the same dictionary (see
+deflateSetDictionary).  For raw inflate, this function can be called
+immediately after inflateInit2() or inflateReset() and before any call of
+inflate() to set the dictionary.  The application must insure that the
+dictionary that was used for compression is provided.
+inflateSetDictionary returns Z_OK if success, Z_STREAM_ERROR if a
+parameter is invalid (e.g.  dictionary being Z_NULL) or the stream state is
+inconsistent, Z_DATA_ERROR if the given dictionary doesn't match the
+expected one (incorrect adler32 value).  inflateSetDictionary does not
+perform any decompression: this will be done by subsequent calls of
+inflate().
+*/
+ZEXTERN int ZEXPORT inflateSync OF((z_streamp strm));
+/*
+Skips invalid compressed data until a full flush point (see above the
+description of deflate with Z_FULL_FLUSH) can be found, or until all
+available input is skipped.  No output is provided.
+inflateSync returns Z_OK if a full flush point has been found, Z_BUF_ERROR
+if no more input was provided, Z_DATA_ERROR if no flush point has been
+found, or Z_STREAM_ERROR if the stream structure was inconsistent.  In the
+success case, the application may save the current current value of total_in
+which indicates where valid compressed data was found.  In the error case,
+the application may repeatedly call inflateSync, providing more input each
+time, until success or end of the input data.
+*/
+ZEXTERN int ZEXPORT inflateCopy OF((z_streamp dest,
+z_streamp source));
+/*
+Sets the destination stream as a complete copy of the source stream.
+This function can be useful when randomly accessing a large stream.  The
+first pass through the stream can periodically record the inflate state,
+allowing restarting inflate at those points when randomly accessing the
+stream.
+inflateCopy returns Z_OK if success, Z_MEM_ERROR if there was not
+enough memory, Z_STREAM_ERROR if the source stream state was inconsistent
+(such as zalloc being Z_NULL).  msg is left unchanged in both source and
+destination.
+*/
+ZEXTERN int ZEXPORT inflateReset OF((z_streamp strm));
+/*
+This function is equivalent to inflateEnd followed by inflateInit,
+but does not free and reallocate all the internal decompression state.  The
+stream will keep attributes that may have been set by inflateInit2.
+inflateReset returns Z_OK if success, or Z_STREAM_ERROR if the source
+stream state was inconsistent (such as zalloc or state being Z_NULL).
+*/
+ZEXTERN int ZEXPORT inflateReset2 OF((z_streamp strm,
+int windowBits));
+/*
+This function is the same as inflateReset, but it also permits changing
+the wrap and window size requests.  The windowBits parameter is interpreted
+the same as it is for inflateInit2.
+inflateReset2 returns Z_OK if success, or Z_STREAM_ERROR if the source
+stream state was inconsistent (such as zalloc or state being Z_NULL), or if
+the windowBits parameter is invalid.
+*/
+ZEXTERN int ZEXPORT inflatePrime OF((z_streamp strm,
+int bits,
+int value));
+/*
+This function inserts bits in the inflate input stream.  The intent is
+that this function is used to start inflating at a bit position in the
+middle of a byte.  The provided bits will be used before any bytes are used
+from next_in.  This function should only be used with raw inflate, and
+should be used before the first inflate() call after inflateInit2() or
+inflateReset().  bits must be less than or equal to 16, and that many of the
+least significant bits of value will be inserted in the input.
+If bits is negative, then the input stream bit buffer is emptied.  Then
+inflatePrime() can be called again to put bits in the buffer.  This is used
+to clear out bits leftover after feeding inflate a block description prior
+to feeding inflate codes.
+inflatePrime returns Z_OK if success, or Z_STREAM_ERROR if the source
+stream state was inconsistent.
+*/
+ZEXTERN long ZEXPORT inflateMark OF((z_streamp strm));
+/*
+This function returns two values, one in the lower 16 bits of the return
+value, and the other in the remaining upper bits, obtained by shifting the
+return value down 16 bits.  If the upper value is -1 and the lower value is
+zero, then inflate() is currently decoding information outside of a block.
+If the upper value is -1 and the lower value is non-zero, then inflate is in
+the middle of a stored block, with the lower value equaling the number of
+bytes from the input remaining to copy.  If the upper value is not -1, then
+it is the number of bits back from the current bit position in the input of
+the code (literal or length/distance pair) currently being processed.  In
+that case the lower value is the number of bytes already emitted for that
+code.
+A code is being processed if inflate is waiting for more input to complete
+decoding of the code, or if it has completed decoding but is waiting for
+more output space to write the literal or match data.
+inflateMark() is used to mark locations in the input data for random
+access, which may be at bit positions, and to note those cases where the
+output of a code may span boundaries of random access blocks.  The current
+location in the input stream can be determined from avail_in and data_type
+as noted in the description for the Z_BLOCK flush parameter for inflate.
+inflateMark returns the value noted above or -1 << 16 if the provided
+source stream state was inconsistent.
+*/
+ZEXTERN int ZEXPORT inflateGetHeader OF((z_streamp strm,
+gz_headerp head));
+/*
+inflateGetHeader() requests that gzip header information be stored in the
+provided gz_header structure.  inflateGetHeader() may be called after
+inflateInit2() or inflateReset(), and before the first call of inflate().
+As inflate() processes the gzip stream, head->done is zero until the header
+is completed, at which time head->done is set to one.  If a zlib stream is
+being decoded, then head->done is set to -1 to indicate that there will be
+no gzip header information forthcoming.  Note that Z_BLOCK or Z_TREES can be
+used to force inflate() to return immediately after header processing is
+complete and before any actual data is decompressed.
+The text, time, xflags, and os fields are filled in with the gzip header
+contents.  hcrc is set to true if there is a header CRC.  (The header CRC
+was valid if done is set to one.) If extra is not Z_NULL, then extra_max
+contains the maximum number of bytes to write to extra.  Once done is true,
+extra_len contains the actual extra field length, and extra contains the
+extra field, or that field truncated if extra_max is less than extra_len.
+If name is not Z_NULL, then up to name_max characters are written there,
+terminated with a zero unless the length is greater than name_max.  If
+comment is not Z_NULL, then up to comm_max characters are written there,
+terminated with a zero unless the length is greater than comm_max.  When any
+of extra, name, or comment are not Z_NULL and the respective field is not
+present in the header, then that field is set to Z_NULL to signal its
+absence.  This allows the use of deflateSetHeader() with the returned
+structure to duplicate the header.  However if those fields are set to
+allocated memory, then the application will need to save those pointers
+elsewhere so that they can be eventually freed.
+If inflateGetHeader is not used, then the header information is simply
+discarded.  The header is always checked for validity, including the header
+CRC if present.  inflateReset() will reset the process to discard the header
+information.  The application would need to call inflateGetHeader() again to
+retrieve the header from the next gzip stream.
+inflateGetHeader returns Z_OK if success, or Z_STREAM_ERROR if the source
+stream state was inconsistent.
+*/
+/*
+ZEXTERN int ZEXPORT inflateBackInit OF((z_streamp strm, int windowBits,
+unsigned char FAR *window));
+Initialize the internal stream state for decompression using inflateBack()
+calls.  The fields zalloc, zfree and opaque in strm must be initialized
+before the call.  If zalloc and zfree are Z_NULL, then the default library-
+derived memory allocation routines are used.  windowBits is the base two
+logarithm of the window size, in the range 8..15.  window is a caller
+supplied buffer of that size.  Except for special applications where it is
+assured that deflate was used with small window sizes, windowBits must be 15
+and a 32K byte window must be supplied to be able to decompress general
+deflate streams.
+See inflateBack() for the usage of these routines.
+inflateBackInit will return Z_OK on success, Z_STREAM_ERROR if any of
+the paramaters are invalid, Z_MEM_ERROR if the internal state could not be
+allocated, or Z_VERSION_ERROR if the version of the library does not match
+the version of the header file.
+*/
+typedef unsigned (*in_func) OF((void FAR *, unsigned char FAR * FAR *));
+typedef int (*out_func) OF((void FAR *, unsigned char FAR *, unsigned));
+ZEXTERN int ZEXPORT inflateBack OF((z_streamp strm,
+in_func in, void FAR *in_desc,
+out_func out, void FAR *out_desc));
+/*
+inflateBack() does a raw inflate with a single call using a call-back
+interface for input and output.  This is more efficient than inflate() for
+file i/o applications in that it avoids copying between the output and the
+sliding window by simply making the window itself the output buffer.  This
+function trusts the application to not change the output buffer passed by
+the output function, at least until inflateBack() returns.
+inflateBackInit() must be called first to allocate the internal state
+and to initialize the state with the user-provided window buffer.
+inflateBack() may then be used multiple times to inflate a complete, raw
+deflate stream with each call.  inflateBackEnd() is then called to free the
+allocated state.
+A raw deflate stream is one with no zlib or gzip header or trailer.
+This routine would normally be used in a utility that reads zip or gzip
+files and writes out uncompressed files.  The utility would decode the
+header and process the trailer on its own, hence this routine expects only
+the raw deflate stream to decompress.  This is different from the normal
+behavior of inflate(), which expects either a zlib or gzip header and
+trailer around the deflate stream.
+inflateBack() uses two subroutines supplied by the caller that are then
+called by inflateBack() for input and output.  inflateBack() calls those
+routines until it reads a complete deflate stream and writes out all of the
+uncompressed data, or until it encounters an error.  The function's
+parameters and return types are defined above in the in_func and out_func
+typedefs.  inflateBack() will call in(in_desc, &buf) which should return the
+number of bytes of provided input, and a pointer to that input in buf.  If
+there is no input available, in() must return zero--buf is ignored in that
+case--and inflateBack() will return a buffer error.  inflateBack() will call
+out(out_desc, buf, len) to write the uncompressed data buf[0..len-1].  out()
+should return zero on success, or non-zero on failure.  If out() returns
+non-zero, inflateBack() will return with an error.  Neither in() nor out()
+are permitted to change the contents of the window provided to
+inflateBackInit(), which is also the buffer that out() uses to write from.
+The length written by out() will be at most the window size.  Any non-zero
+amount of input may be provided by in().
+For convenience, inflateBack() can be provided input on the first call by
+setting strm->next_in and strm->avail_in.  If that input is exhausted, then
+in() will be called.  Therefore strm->next_in must be initialized before
+calling inflateBack().  If strm->next_in is Z_NULL, then in() will be called
+immediately for input.  If strm->next_in is not Z_NULL, then strm->avail_in
+must also be initialized, and then if strm->avail_in is not zero, input will
+initially be taken from strm->next_in[0 ..  strm->avail_in - 1].
+The in_desc and out_desc parameters of inflateBack() is passed as the
+first parameter of in() and out() respectively when they are called.  These
+descriptors can be optionally used to pass any information that the caller-
+supplied in() and out() functions need to do their job.
+On return, inflateBack() will set strm->next_in and strm->avail_in to
+pass back any unused input that was provided by the last in() call.  The
+return values of inflateBack() can be Z_STREAM_END on success, Z_BUF_ERROR
+if in() or out() returned an error, Z_DATA_ERROR if there was a format error
+in the deflate stream (in which case strm->msg is set to indicate the nature
+of the error), or Z_STREAM_ERROR if the stream was not properly initialized.
+In the case of Z_BUF_ERROR, an input or output error can be distinguished
+using strm->next_in which will be Z_NULL only if in() returned an error.  If
+strm->next_in is not Z_NULL, then the Z_BUF_ERROR was due to out() returning
+non-zero.  (in() will always be called before out(), so strm->next_in is
+assured to be defined if out() returns non-zero.) Note that inflateBack()
+cannot return Z_OK.
+*/
+ZEXTERN int ZEXPORT inflateBackEnd OF((z_streamp strm));
+/*
+All memory allocated by inflateBackInit() is freed.
+inflateBackEnd() returns Z_OK on success, or Z_STREAM_ERROR if the stream
+state was inconsistent.
+*/
+ZEXTERN uLong ZEXPORT zlibCompileFlags OF((void));
+/* Return flags indicating compile-time options.
+Type sizes, two bits each, 00 = 16 bits, 01 = 32, 10 = 64, 11 = other:
+1.0: size of uInt
+3.2: size of uLong
+5.4: size of voidpf (pointer)
+7.6: size of z_off_t
+Compiler, assembler, and debug options:
+8: DEBUG
+9: ASMV or ASMINF -- use ASM code
+10: ZLIB_WINAPI -- exported functions use the WINAPI calling convention
+11: 0 (reserved)
+One-time table building (smaller code, but not thread-safe if true):
+12: BUILDFIXED -- build static block decoding tables when needed
+13: DYNAMIC_CRC_TABLE -- build CRC calculation tables when needed
+14,15: 0 (reserved)
+Library content (indicates missing functionality):
+16: NO_GZCOMPRESS -- gz* functions cannot compress (to avoid linking
+deflate code when not needed)
+17: NO_GZIP -- deflate can't write gzip streams, and inflate can't detect
+and decode gzip streams (to avoid linking crc code)
+18-19: 0 (reserved)
+Operation variations (changes in library functionality):
+20: PKZIP_BUG_WORKAROUND -- slightly more permissive inflate
+21: FASTEST -- deflate algorithm with only one, lowest compression level
+22,23: 0 (reserved)
+The sprintf variant used by gzprintf (zero is best):
+24: 0 = vs*, 1 = s* -- 1 means limited to 20 arguments after the format
+25: 0 = *nprintf, 1 = *printf -- 1 means gzprintf() not secure!
+26: 0 = returns value, 1 = void -- 1 means inferred string length returned
+Remainder:
+27-31: 0 (reserved)
+*/
+/* utility functions */
+/*
+The following utility functions are implemented on top of the basic
+stream-oriented functions.  To simplify the interface, some default options
+are assumed (compression level and memory usage, standard memory allocation
+functions).  The source code of these utility functions can be modified if
+you need special options.
+*/
+ZEXTERN int ZEXPORT compress OF((Bytef *dest,   uLongf *destLen,
+const Bytef *source, uLong sourceLen));
+/*
+Compresses the source buffer into the destination buffer.  sourceLen is
+the byte length of the source buffer.  Upon entry, destLen is the total size
+of the destination buffer, which must be at least the value returned by
+compressBound(sourceLen).  Upon exit, destLen is the actual size of the
+compressed buffer.
+compress returns Z_OK if success, Z_MEM_ERROR if there was not
+enough memory, Z_BUF_ERROR if there was not enough room in the output
+buffer.
+*/
+ZEXTERN int ZEXPORT compress2 OF((Bytef *dest,   uLongf *destLen,
+const Bytef *source, uLong sourceLen,
+int level));
+/*
+Compresses the source buffer into the destination buffer.  The level
+parameter has the same meaning as in deflateInit.  sourceLen is the byte
+length of the source buffer.  Upon entry, destLen is the total size of the
+destination buffer, which must be at least the value returned by
+compressBound(sourceLen).  Upon exit, destLen is the actual size of the
+compressed buffer.
+compress2 returns Z_OK if success, Z_MEM_ERROR if there was not enough
+memory, Z_BUF_ERROR if there was not enough room in the output buffer,
+Z_STREAM_ERROR if the level parameter is invalid.
+*/
+ZEXTERN uLong ZEXPORT compressBound OF((uLong sourceLen));
+/*
+compressBound() returns an upper bound on the compressed size after
+compress() or compress2() on sourceLen bytes.  It would be used before a
+compress() or compress2() call to allocate the destination buffer.
+*/
+ZEXTERN int ZEXPORT uncompress OF((Bytef *dest,   uLongf *destLen,
+const Bytef *source, uLong sourceLen));
+/*
+Decompresses the source buffer into the destination buffer.  sourceLen is
+the byte length of the source buffer.  Upon entry, destLen is the total size
+of the destination buffer, which must be large enough to hold the entire
+uncompressed data.  (The size of the uncompressed data must have been saved
+previously by the compressor and transmitted to the decompressor by some
+mechanism outside the scope of this compression library.) Upon exit, destLen
+is the actual size of the uncompressed buffer.
+uncompress returns Z_OK if success, Z_MEM_ERROR if there was not
+enough memory, Z_BUF_ERROR if there was not enough room in the output
+buffer, or Z_DATA_ERROR if the input data was corrupted or incomplete.
+*/
+/* gzip file access functions */
+/*
+This library supports reading and writing files in gzip (.gz) format with
+an interface similar to that of stdio, using the functions that start with
+"gz".  The gzip format is different from the zlib format.  gzip is a gzip
+wrapper, documented in RFC 1952, wrapped around a deflate stream.
+*/
+typedef voidp gzFile;       /* opaque gzip file descriptor */
+/*
+ZEXTERN gzFile ZEXPORT gzopen OF((const char *path, const char *mode));
+Opens a gzip (.gz) file for reading or writing.  The mode parameter is as
+in fopen ("rb" or "wb") but can also include a compression level ("wb9") or
+a strategy: 'f' for filtered data as in "wb6f", 'h' for Huffman-only
+compression as in "wb1h", 'R' for run-length encoding as in "wb1R", or 'F'
+for fixed code compression as in "wb9F".  (See the description of
+deflateInit2 for more information about the strategy parameter.) Also "a"
+can be used instead of "w" to request that the gzip stream that will be
+written be appended to the file.  "+" will result in an error, since reading
+and writing to the same gzip file is not supported.
+gzopen can be used to read a file which is not in gzip format; in this
+case gzread will directly read from the file without decompression.
+gzopen returns NULL if the file could not be opened, if there was
+insufficient memory to allocate the gzFile state, or if an invalid mode was
+specified (an 'r', 'w', or 'a' was not provided, or '+' was provided).
+errno can be checked to determine if the reason gzopen failed was that the
+file could not be opened.
+*/
+ZEXTERN gzFile ZEXPORT gzdopen OF((int fd, const char *mode));
+/*
+gzdopen associates a gzFile with the file descriptor fd.  File descriptors
+are obtained from calls like open, dup, creat, pipe or fileno (if the file
+has been previously opened with fopen).  The mode parameter is as in gzopen.
+The next call of gzclose on the returned gzFile will also close the file
+descriptor fd, just like fclose(fdopen(fd, mode)) closes the file descriptor
+fd.  If you want to keep fd open, use fd = dup(fd_keep); gz = gzdopen(fd,
+mode);.  The duplicated descriptor should be saved to avoid a leak, since
+gzdopen does not close fd if it fails.
+gzdopen returns NULL if there was insufficient memory to allocate the
+gzFile state, if an invalid mode was specified (an 'r', 'w', or 'a' was not
+provided, or '+' was provided), or if fd is -1.  The file descriptor is not
+used until the next gz* read, write, seek, or close operation, so gzdopen
+will not detect if fd is invalid (unless fd is -1).
+*/
+ZEXTERN int ZEXPORT gzbuffer OF((gzFile file, unsigned size));
+/*
+Set the internal buffer size used by this library's functions.  The
+default buffer size is 8192 bytes.  This function must be called after
+gzopen() or gzdopen(), and before any other calls that read or write the
+file.  The buffer memory allocation is always deferred to the first read or
+write.  Two buffers are allocated, either both of the specified size when
+writing, or one of the specified size and the other twice that size when
+reading.  A larger buffer size of, for example, 64K or 128K bytes will
+noticeably increase the speed of decompression (reading).
+The new buffer size also affects the maximum length for gzprintf().
+gzbuffer() returns 0 on success, or -1 on failure, such as being called
+too late.
+*/
+ZEXTERN int ZEXPORT gzsetparams OF((gzFile file, int level, int strategy));
+/*
+Dynamically update the compression level or strategy.  See the description
+of deflateInit2 for the meaning of these parameters.
+gzsetparams returns Z_OK if success, or Z_STREAM_ERROR if the file was not
+opened for writing.
+*/
+ZEXTERN int ZEXPORT gzread OF((gzFile file, voidp buf, unsigned len));
+/*
+Reads the given number of uncompressed bytes from the compressed file.  If
+the input file was not in gzip format, gzread copies the given number of
+bytes into the buffer.
+After reaching the end of a gzip stream in the input, gzread will continue
+to read, looking for another gzip stream, or failing that, reading the rest
+of the input file directly without decompression.  The entire input file
+will be read if gzread is called until it returns less than the requested
+len.
+gzread returns the number of uncompressed bytes actually read, less than
+len for end of file, or -1 for error.
+*/
+ZEXTERN int ZEXPORT gzwrite OF((gzFile file,
+voidpc buf, unsigned len));
+/*
+Writes the given number of uncompressed bytes into the compressed file.
+gzwrite returns the number of uncompressed bytes written or 0 in case of
+error.
+*/
+ZEXTERN int ZEXPORTVA gzprintf OF((gzFile file, const char *format, ...));
+/*
+Converts, formats, and writes the arguments to the compressed file under
+control of the format string, as in fprintf.  gzprintf returns the number of
+uncompressed bytes actually written, or 0 in case of error.  The number of
+uncompressed bytes written is limited to 8191, or one less than the buffer
+size given to gzbuffer().  The caller should assure that this limit is not
+exceeded.  If it is exceeded, then gzprintf() will return an error (0) with
+nothing written.  In this case, there may also be a buffer overflow with
+unpredictable consequences, which is possible only if zlib was compiled with
+the insecure functions sprintf() or vsprintf() because the secure snprintf()
+or vsnprintf() functions were not available.  This can be determined using
+zlibCompileFlags().
+*/
+ZEXTERN int ZEXPORT gzputs OF((gzFile file, const char *s));
+/*
+Writes the given null-terminated string to the compressed file, excluding
+the terminating null character.
+gzputs returns the number of characters written, or -1 in case of error.
+*/
+ZEXTERN char * ZEXPORT gzgets OF((gzFile file, char *buf, int len));
+/*
+Reads bytes from the compressed file until len-1 characters are read, or a
+newline character is read and transferred to buf, or an end-of-file
+condition is encountered.  If any characters are read or if len == 1, the
+string is terminated with a null character.  If no characters are read due
+to an end-of-file or len < 1, then the buffer is left untouched.
+gzgets returns buf which is a null-terminated string, or it returns NULL
+for end-of-file or in case of error.  If there was an error, the contents at
+buf are indeterminate.
+*/
+ZEXTERN int ZEXPORT gzputc OF((gzFile file, int c));
+/*
+Writes c, converted to an unsigned char, into the compressed file.  gzputc
+returns the value that was written, or -1 in case of error.
+*/
+ZEXTERN int ZEXPORT gzgetc OF((gzFile file));
+/*
+Reads one byte from the compressed file.  gzgetc returns this byte or -1
+in case of end of file or error.
+*/
+ZEXTERN int ZEXPORT gzungetc OF((int c, gzFile file));
+/*
+Push one character back onto the stream to be read as the first character
+on the next read.  At least one character of push-back is allowed.
+gzungetc() returns the character pushed, or -1 on failure.  gzungetc() will
+fail if c is -1, and may fail if a character has been pushed but not read
+yet.  If gzungetc is used immediately after gzopen or gzdopen, at least the
+output buffer size of pushed characters is allowed.  (See gzbuffer above.)
+The pushed character will be discarded if the stream is repositioned with
+gzseek() or gzrewind().
+*/
+ZEXTERN int ZEXPORT gzflush OF((gzFile file, int flush));
+/*
+Flushes all pending output into the compressed file.  The parameter flush
+is as in the deflate() function.  The return value is the zlib error number
+(see function gzerror below).  gzflush is only permitted when writing.
+If the flush parameter is Z_FINISH, the remaining data is written and the
+gzip stream is completed in the output.  If gzwrite() is called again, a new
+gzip stream will be started in the output.  gzread() is able to read such
+concatented gzip streams.
+gzflush should be called only when strictly necessary because it will
+degrade compression if called too often.
+*/
+/*
+ZEXTERN z_off_t ZEXPORT gzseek OF((gzFile file,
+z_off_t offset, int whence));
+Sets the starting position for the next gzread or gzwrite on the given
+compressed file.  The offset represents a number of bytes in the
+uncompressed data stream.  The whence parameter is defined as in lseek(2);
+the value SEEK_END is not supported.
+If the file is opened for reading, this function is emulated but can be
+extremely slow.  If the file is opened for writing, only forward seeks are
+supported; gzseek then compresses a sequence of zeroes up to the new
+starting position.
+gzseek returns the resulting offset location as measured in bytes from
+the beginning of the uncompressed stream, or -1 in case of error, in
+particular if the file is opened for writing and the new starting position
+would be before the current position.
+*/
+ZEXTERN int ZEXPORT    gzrewind OF((gzFile file));
+/*
+Rewinds the given file. This function is supported only for reading.
+gzrewind(file) is equivalent to (int)gzseek(file, 0L, SEEK_SET)
+*/
+/*
+ZEXTERN z_off_t ZEXPORT    gztell OF((gzFile file));
+Returns the starting position for the next gzread or gzwrite on the given
+compressed file.  This position represents a number of bytes in the
+uncompressed data stream, and is zero when starting, even if appending or
+reading a gzip stream from the middle of a file using gzdopen().
+gztell(file) is equivalent to gzseek(file, 0L, SEEK_CUR)
+*/
+/*
+ZEXTERN z_off_t ZEXPORT gzoffset OF((gzFile file));
+Returns the current offset in the file being read or written.  This offset
+includes the count of bytes that precede the gzip stream, for example when
+appending or when using gzdopen() for reading.  When reading, the offset
+does not include as yet unused buffered input.  This information can be used
+for a progress indicator.  On error, gzoffset() returns -1.
+*/
+ZEXTERN int ZEXPORT gzeof OF((gzFile file));
+/*
+Returns true (1) if the end-of-file indicator has been set while reading,
+false (0) otherwise.  Note that the end-of-file indicator is set only if the
+read tried to go past the end of the input, but came up short.  Therefore,
+just like feof(), gzeof() may return false even if there is no more data to
+read, in the event that the last read request was for the exact number of
+bytes remaining in the input file.  This will happen if the input file size
+is an exact multiple of the buffer size.
+If gzeof() returns true, then the read functions will return no more data,
+unless the end-of-file indicator is reset by gzclearerr() and the input file
+has grown since the previous end of file was detected.
+*/
+ZEXTERN int ZEXPORT gzdirect OF((gzFile file));
+/*
+Returns true (1) if file is being copied directly while reading, or false
+(0) if file is a gzip stream being decompressed.  This state can change from
+false to true while reading the input file if the end of a gzip stream is
+reached, but is followed by data that is not another gzip stream.
+If the input file is empty, gzdirect() will return true, since the input
+does not contain a gzip stream.
+If gzdirect() is used immediately after gzopen() or gzdopen() it will
+cause buffers to be allocated to allow reading the file to determine if it
+is a gzip file.  Therefore if gzbuffer() is used, it should be called before
+gzdirect().
+*/
+ZEXTERN int ZEXPORT    gzclose OF((gzFile file));
+/*
+Flushes all pending output if necessary, closes the compressed file and
+deallocates the (de)compression state.  Note that once file is closed, you
+cannot call gzerror with file, since its structures have been deallocated.
+gzclose must not be called more than once on the same file, just as free
+must not be called more than once on the same allocation.
+gzclose will return Z_STREAM_ERROR if file is not valid, Z_ERRNO on a
+file operation error, or Z_OK on success.
+*/
+ZEXTERN int ZEXPORT gzclose_r OF((gzFile file));
+ZEXTERN int ZEXPORT gzclose_w OF((gzFile file));
+/*
+Same as gzclose(), but gzclose_r() is only for use when reading, and
+gzclose_w() is only for use when writing or appending.  The advantage to
+using these instead of gzclose() is that they avoid linking in zlib
+compression or decompression code that is not used when only reading or only
+writing respectively.  If gzclose() is used, then both compression and
+decompression code will be included the application when linking to a static
+zlib library.
+*/
+ZEXTERN const char * ZEXPORT gzerror OF((gzFile file, int *errnum));
+/*
+Returns the error message for the last error which occurred on the given
+compressed file.  errnum is set to zlib error number.  If an error occurred
+in the file system and not in the compression library, errnum is set to
+Z_ERRNO and the application may consult errno to get the exact error code.
+The application must not modify the returned string.  Future calls to
+this function may invalidate the previously returned string.  If file is
+closed, then the string previously returned by gzerror will no longer be
+available.
+gzerror() should be used to distinguish errors from end-of-file for those
+functions above that do not distinguish those cases in their return values.
+*/
+ZEXTERN void ZEXPORT gzclearerr OF((gzFile file));
+/*
+Clears the error and end-of-file flags for file.  This is analogous to the
+clearerr() function in stdio.  This is useful for continuing to read a gzip
+file that is being written concurrently.
+*/
+/* checksum functions */
+/*
+These functions are not related to compression but are exported
+anyway because they might be useful in applications using the compression
+library.
+*/
+ZEXTERN uLong ZEXPORT adler32 OF((uLong adler, const Bytef *buf, uInt len));
+/*
+Update a running Adler-32 checksum with the bytes buf[0..len-1] and
+return the updated checksum.  If buf is Z_NULL, this function returns the
+required initial value for the checksum.
+An Adler-32 checksum is almost as reliable as a CRC32 but can be computed
+much faster.
+Usage example:
+uLong adler = adler32(0L, Z_NULL, 0);
+while (read_buffer(buffer, length) != EOF) {
+adler = adler32(adler, buffer, length);
+}
+if (adler != original_adler) error();
+*/
+/*
+ZEXTERN uLong ZEXPORT adler32_combine OF((uLong adler1, uLong adler2,
+z_off_t len2));
+Combine two Adler-32 checksums into one.  For two sequences of bytes, seq1
+and seq2 with lengths len1 and len2, Adler-32 checksums were calculated for
+each, adler1 and adler2.  adler32_combine() returns the Adler-32 checksum of
+seq1 and seq2 concatenated, requiring only adler1, adler2, and len2.
+*/
+ZEXTERN uLong ZEXPORT crc32   OF((uLong crc, const Bytef *buf, uInt len));
+/*
+Update a running CRC-32 with the bytes buf[0..len-1] and return the
+updated CRC-32.  If buf is Z_NULL, this function returns the required
+initial value for the for the crc.  Pre- and post-conditioning (one's
+complement) is performed within this function so it shouldn't be done by the
+application.
+Usage example:
+uLong crc = crc32(0L, Z_NULL, 0);
+while (read_buffer(buffer, length) != EOF) {
+crc = crc32(crc, buffer, length);
+}
+if (crc != original_crc) error();
+*/
+/*
+ZEXTERN uLong ZEXPORT crc32_combine OF((uLong crc1, uLong crc2, z_off_t len2));
+Combine two CRC-32 check values into one.  For two sequences of bytes,
+seq1 and seq2 with lengths len1 and len2, CRC-32 check values were
+calculated for each, crc1 and crc2.  crc32_combine() returns the CRC-32
+check value of seq1 and seq2 concatenated, requiring only crc1, crc2, and
+len2.
+*/
+/* various hacks, don't look :) */
+/* deflateInit and inflateInit are macros to allow checking the zlib version
+* and the compiler's view of z_stream:
+*/
+ZEXTERN int ZEXPORT deflateInit_ OF((z_streamp strm, int level,
+const char *version, int stream_size));
+ZEXTERN int ZEXPORT inflateInit_ OF((z_streamp strm,
+const char *version, int stream_size));
+ZEXTERN int ZEXPORT deflateInit2_ OF((z_streamp strm, int  level, int  method,
+int windowBits, int memLevel,
+int strategy, const char *version,
+int stream_size));
+ZEXTERN int ZEXPORT inflateInit2_ OF((z_streamp strm, int  windowBits,
+const char *version, int stream_size));
+ZEXTERN int ZEXPORT inflateBackInit_ OF((z_streamp strm, int windowBits,
+unsigned char FAR *window,
+const char *version,
+int stream_size));
+#define deflateInit(strm, level) \
+deflateInit_((strm), (level),       ZLIB_VERSION, sizeof(z_stream))
+#define inflateInit(strm) \
+inflateInit_((strm),                ZLIB_VERSION, sizeof(z_stream))
+#define deflateInit2(strm, level, method, windowBits, memLevel, strategy) \
+deflateInit2_((strm),(level),(method),(windowBits),(memLevel),\
+(strategy),           ZLIB_VERSION, sizeof(z_stream))
+#define inflateInit2(strm, windowBits) \
+inflateInit2_((strm), (windowBits), ZLIB_VERSION, sizeof(z_stream))
+#define inflateBackInit(strm, windowBits, window) \
+inflateBackInit_((strm), (windowBits), (window), \
+ZLIB_VERSION, sizeof(z_stream))
+/* provide 64-bit offset functions if _LARGEFILE64_SOURCE defined, and/or
+* change the regular functions to 64 bits if _FILE_OFFSET_BITS is 64 (if
+* both are true, the application gets the *64 functions, and the regular
+* functions are changed to 64 bits) -- in case these are set on systems
+* without large file support, _LFS64_LARGEFILE must also be true
+*/
+#if defined(_LARGEFILE64_SOURCE) && _LFS64_LARGEFILE-0
+ZEXTERN gzFile ZEXPORT gzopen64 OF((const char *, const char *));
+ZEXTERN z_off64_t ZEXPORT gzseek64 OF((gzFile, z_off64_t, int));
+ZEXTERN z_off64_t ZEXPORT gztell64 OF((gzFile));
+ZEXTERN z_off64_t ZEXPORT gzoffset64 OF((gzFile));
+ZEXTERN uLong ZEXPORT adler32_combine64 OF((uLong, uLong, z_off64_t));
+ZEXTERN uLong ZEXPORT crc32_combine64 OF((uLong, uLong, z_off64_t));
+#endif
+#if !defined(ZLIB_INTERNAL) && _FILE_OFFSET_BITS-0 == 64 && _LFS64_LARGEFILE-0
+#  define gzopen gzopen64
+#  define gzseek gzseek64
+#  define gztell gztell64
+#  define gzoffset gzoffset64
+#  define adler32_combine adler32_combine64
+#  define crc32_combine crc32_combine64
+#  ifdef _LARGEFILE64_SOURCE
+ZEXTERN gzFile ZEXPORT gzopen64 OF((const char *, const char *));
+ZEXTERN z_off_t ZEXPORT gzseek64 OF((gzFile, z_off_t, int));
+ZEXTERN z_off_t ZEXPORT gztell64 OF((gzFile));
+ZEXTERN z_off_t ZEXPORT gzoffset64 OF((gzFile));
+ZEXTERN uLong ZEXPORT adler32_combine64 OF((uLong, uLong, z_off_t));
+ZEXTERN uLong ZEXPORT crc32_combine64 OF((uLong, uLong, z_off_t));
+#  endif
+#else
+ZEXTERN gzFile ZEXPORT gzopen OF((const char *, const char *));
+ZEXTERN z_off_t ZEXPORT gzseek OF((gzFile, z_off_t, int));
+ZEXTERN z_off_t ZEXPORT gztell OF((gzFile));
+ZEXTERN z_off_t ZEXPORT gzoffset OF((gzFile));
+ZEXTERN uLong ZEXPORT adler32_combine OF((uLong, uLong, z_off_t));
+ZEXTERN uLong ZEXPORT crc32_combine OF((uLong, uLong, z_off_t));
+#endif
+/* hack for buggy compilers */
+#if !defined(ZUTIL_H) && !defined(NO_DUMMY_DECL)
+struct internal_state {int dummy;};
+#endif
+/* undocumented functions */
+ZEXTERN const char   * ZEXPORT zError           OF((int));
+ZEXTERN int            ZEXPORT inflateSyncPoint OF((z_streamp));
+ZEXTERN const uLongf * ZEXPORT get_crc_table    OF((void));
+ZEXTERN int            ZEXPORT inflateUndermine OF((z_streamp, int));
+#ifdef __cplusplus
+}
+#endif
+#endif /* ZLIB_H */