jdk/src/share/native/java/util/zip/zlib-1.2.8/zlib.h
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     1 /*
       
     2  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
       
     3  *
       
     4  * This code is free software; you can redistribute it and/or modify it
       
     5  * under the terms of the GNU General Public License version 2 only, as
       
     6  * published by the Free Software Foundation.  Oracle designates this
       
     7  * particular file as subject to the "Classpath" exception as provided
       
     8  * by Oracle in the LICENSE file that accompanied this code.
       
     9  *
       
    10  * This code is distributed in the hope that it will be useful, but WITHOUT
       
    11  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
       
    12  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
       
    13  * version 2 for more details (a copy is included in the LICENSE file that
       
    14  * accompanied this code).
       
    15  *
       
    16  * You should have received a copy of the GNU General Public License version
       
    17  * 2 along with this work; if not, write to the Free Software Foundation,
       
    18  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
       
    19  *
       
    20  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
       
    21  * or visit www.oracle.com if you need additional information or have any
       
    22  * questions.
       
    23  */
       
    24 
       
    25 /* zlib.h -- interface of the 'zlib' general purpose compression library
       
    26   version 1.2.8, April 28th, 2013
       
    27 
       
    28   Copyright (C) 1995-2013 Jean-loup Gailly and Mark Adler
       
    29 
       
    30   This software is provided 'as-is', without any express or implied
       
    31   warranty.  In no event will the authors be held liable for any damages
       
    32   arising from the use of this software.
       
    33 
       
    34   Permission is granted to anyone to use this software for any purpose,
       
    35   including commercial applications, and to alter it and redistribute it
       
    36   freely, subject to the following restrictions:
       
    37 
       
    38   1. The origin of this software must not be misrepresented; you must not
       
    39      claim that you wrote the original software. If you use this software
       
    40      in a product, an acknowledgment in the product documentation would be
       
    41      appreciated but is not required.
       
    42   2. Altered source versions must be plainly marked as such, and must not be
       
    43      misrepresented as being the original software.
       
    44   3. This notice may not be removed or altered from any source distribution.
       
    45 
       
    46   Jean-loup Gailly        Mark Adler
       
    47   jloup@gzip.org          madler@alumni.caltech.edu
       
    48 
       
    49 
       
    50   The data format used by the zlib library is described by RFCs (Request for
       
    51   Comments) 1950 to 1952 in the files http://tools.ietf.org/html/rfc1950
       
    52   (zlib format), rfc1951 (deflate format) and rfc1952 (gzip format).
       
    53 */
       
    54 
       
    55 #ifndef ZLIB_H
       
    56 #define ZLIB_H
       
    57 
       
    58 #include "zconf.h"
       
    59 
       
    60 #ifdef __cplusplus
       
    61 extern "C" {
       
    62 #endif
       
    63 
       
    64 #define ZLIB_VERSION "1.2.8"
       
    65 #define ZLIB_VERNUM 0x1280
       
    66 #define ZLIB_VER_MAJOR 1
       
    67 #define ZLIB_VER_MINOR 2
       
    68 #define ZLIB_VER_REVISION 8
       
    69 #define ZLIB_VER_SUBREVISION 0
       
    70 
       
    71 /*
       
    72     The 'zlib' compression library provides in-memory compression and
       
    73   decompression functions, including integrity checks of the uncompressed data.
       
    74   This version of the library supports only one compression method (deflation)
       
    75   but other algorithms will be added later and will have the same stream
       
    76   interface.
       
    77 
       
    78     Compression can be done in a single step if the buffers are large enough,
       
    79   or can be done by repeated calls of the compression function.  In the latter
       
    80   case, the application must provide more input and/or consume the output
       
    81   (providing more output space) before each call.
       
    82 
       
    83     The compressed data format used by default by the in-memory functions is
       
    84   the zlib format, which is a zlib wrapper documented in RFC 1950, wrapped
       
    85   around a deflate stream, which is itself documented in RFC 1951.
       
    86 
       
    87     The library also supports reading and writing files in gzip (.gz) format
       
    88   with an interface similar to that of stdio using the functions that start
       
    89   with "gz".  The gzip format is different from the zlib format.  gzip is a
       
    90   gzip wrapper, documented in RFC 1952, wrapped around a deflate stream.
       
    91 
       
    92     This library can optionally read and write gzip streams in memory as well.
       
    93 
       
    94     The zlib format was designed to be compact and fast for use in memory
       
    95   and on communications channels.  The gzip format was designed for single-
       
    96   file compression on file systems, has a larger header than zlib to maintain
       
    97   directory information, and uses a different, slower check method than zlib.
       
    98 
       
    99     The library does not install any signal handler.  The decoder checks
       
   100   the consistency of the compressed data, so the library should never crash
       
   101   even in case of corrupted input.
       
   102 */
       
   103 
       
   104 typedef voidpf (*alloc_func) OF((voidpf opaque, uInt items, uInt size));
       
   105 typedef void   (*free_func)  OF((voidpf opaque, voidpf address));
       
   106 
       
   107 struct internal_state;
       
   108 
       
   109 typedef struct z_stream_s {
       
   110     z_const Bytef *next_in;     /* next input byte */
       
   111     uInt     avail_in;  /* number of bytes available at next_in */
       
   112     uLong    total_in;  /* total number of input bytes read so far */
       
   113 
       
   114     Bytef    *next_out; /* next output byte should be put there */
       
   115     uInt     avail_out; /* remaining free space at next_out */
       
   116     uLong    total_out; /* total number of bytes output so far */
       
   117 
       
   118     z_const char *msg;  /* last error message, NULL if no error */
       
   119     struct internal_state FAR *state; /* not visible by applications */
       
   120 
       
   121     alloc_func zalloc;  /* used to allocate the internal state */
       
   122     free_func  zfree;   /* used to free the internal state */
       
   123     voidpf     opaque;  /* private data object passed to zalloc and zfree */
       
   124 
       
   125     int     data_type;  /* best guess about the data type: binary or text */
       
   126     uLong   adler;      /* adler32 value of the uncompressed data */
       
   127     uLong   reserved;   /* reserved for future use */
       
   128 } z_stream;
       
   129 
       
   130 typedef z_stream FAR *z_streamp;
       
   131 
       
   132 /*
       
   133      gzip header information passed to and from zlib routines.  See RFC 1952
       
   134   for more details on the meanings of these fields.
       
   135 */
       
   136 typedef struct gz_header_s {
       
   137     int     text;       /* true if compressed data believed to be text */
       
   138     uLong   time;       /* modification time */
       
   139     int     xflags;     /* extra flags (not used when writing a gzip file) */
       
   140     int     os;         /* operating system */
       
   141     Bytef   *extra;     /* pointer to extra field or Z_NULL if none */
       
   142     uInt    extra_len;  /* extra field length (valid if extra != Z_NULL) */
       
   143     uInt    extra_max;  /* space at extra (only when reading header) */
       
   144     Bytef   *name;      /* pointer to zero-terminated file name or Z_NULL */
       
   145     uInt    name_max;   /* space at name (only when reading header) */
       
   146     Bytef   *comment;   /* pointer to zero-terminated comment or Z_NULL */
       
   147     uInt    comm_max;   /* space at comment (only when reading header) */
       
   148     int     hcrc;       /* true if there was or will be a header crc */
       
   149     int     done;       /* true when done reading gzip header (not used
       
   150                            when writing a gzip file) */
       
   151 } gz_header;
       
   152 
       
   153 typedef gz_header FAR *gz_headerp;
       
   154 
       
   155 /*
       
   156      The application must update next_in and avail_in when avail_in has dropped
       
   157    to zero.  It must update next_out and avail_out when avail_out has dropped
       
   158    to zero.  The application must initialize zalloc, zfree and opaque before
       
   159    calling the init function.  All other fields are set by the compression
       
   160    library and must not be updated by the application.
       
   161 
       
   162      The opaque value provided by the application will be passed as the first
       
   163    parameter for calls of zalloc and zfree.  This can be useful for custom
       
   164    memory management.  The compression library attaches no meaning to the
       
   165    opaque value.
       
   166 
       
   167      zalloc must return Z_NULL if there is not enough memory for the object.
       
   168    If zlib is used in a multi-threaded application, zalloc and zfree must be
       
   169    thread safe.
       
   170 
       
   171      On 16-bit systems, the functions zalloc and zfree must be able to allocate
       
   172    exactly 65536 bytes, but will not be required to allocate more than this if
       
   173    the symbol MAXSEG_64K is defined (see zconf.h).  WARNING: On MSDOS, pointers
       
   174    returned by zalloc for objects of exactly 65536 bytes *must* have their
       
   175    offset normalized to zero.  The default allocation function provided by this
       
   176    library ensures this (see zutil.c).  To reduce memory requirements and avoid
       
   177    any allocation of 64K objects, at the expense of compression ratio, compile
       
   178    the library with -DMAX_WBITS=14 (see zconf.h).
       
   179 
       
   180      The fields total_in and total_out can be used for statistics or progress
       
   181    reports.  After compression, total_in holds the total size of the
       
   182    uncompressed data and may be saved for use in the decompressor (particularly
       
   183    if the decompressor wants to decompress everything in a single step).
       
   184 */
       
   185 
       
   186                         /* constants */
       
   187 
       
   188 #define Z_NO_FLUSH      0
       
   189 #define Z_PARTIAL_FLUSH 1
       
   190 #define Z_SYNC_FLUSH    2
       
   191 #define Z_FULL_FLUSH    3
       
   192 #define Z_FINISH        4
       
   193 #define Z_BLOCK         5
       
   194 #define Z_TREES         6
       
   195 /* Allowed flush values; see deflate() and inflate() below for details */
       
   196 
       
   197 #define Z_OK            0
       
   198 #define Z_STREAM_END    1
       
   199 #define Z_NEED_DICT     2
       
   200 #define Z_ERRNO        (-1)
       
   201 #define Z_STREAM_ERROR (-2)
       
   202 #define Z_DATA_ERROR   (-3)
       
   203 #define Z_MEM_ERROR    (-4)
       
   204 #define Z_BUF_ERROR    (-5)
       
   205 #define Z_VERSION_ERROR (-6)
       
   206 /* Return codes for the compression/decompression functions. Negative values
       
   207  * are errors, positive values are used for special but normal events.
       
   208  */
       
   209 
       
   210 #define Z_NO_COMPRESSION         0
       
   211 #define Z_BEST_SPEED             1
       
   212 #define Z_BEST_COMPRESSION       9
       
   213 #define Z_DEFAULT_COMPRESSION  (-1)
       
   214 /* compression levels */
       
   215 
       
   216 #define Z_FILTERED            1
       
   217 #define Z_HUFFMAN_ONLY        2
       
   218 #define Z_RLE                 3
       
   219 #define Z_FIXED               4
       
   220 #define Z_DEFAULT_STRATEGY    0
       
   221 /* compression strategy; see deflateInit2() below for details */
       
   222 
       
   223 #define Z_BINARY   0
       
   224 #define Z_TEXT     1
       
   225 #define Z_ASCII    Z_TEXT   /* for compatibility with 1.2.2 and earlier */
       
   226 #define Z_UNKNOWN  2
       
   227 /* Possible values of the data_type field (though see inflate()) */
       
   228 
       
   229 #define Z_DEFLATED   8
       
   230 /* The deflate compression method (the only one supported in this version) */
       
   231 
       
   232 #define Z_NULL  0  /* for initializing zalloc, zfree, opaque */
       
   233 
       
   234 #define zlib_version zlibVersion()
       
   235 /* for compatibility with versions < 1.0.2 */
       
   236 
       
   237 
       
   238                         /* basic functions */
       
   239 
       
   240 ZEXTERN const char * ZEXPORT zlibVersion OF((void));
       
   241 /* The application can compare zlibVersion and ZLIB_VERSION for consistency.
       
   242    If the first character differs, the library code actually used is not
       
   243    compatible with the zlib.h header file used by the application.  This check
       
   244    is automatically made by deflateInit and inflateInit.
       
   245  */
       
   246 
       
   247 /*
       
   248 ZEXTERN int ZEXPORT deflateInit OF((z_streamp strm, int level));
       
   249 
       
   250      Initializes the internal stream state for compression.  The fields
       
   251    zalloc, zfree and opaque must be initialized before by the caller.  If
       
   252    zalloc and zfree are set to Z_NULL, deflateInit updates them to use default
       
   253    allocation functions.
       
   254 
       
   255      The compression level must be Z_DEFAULT_COMPRESSION, or between 0 and 9:
       
   256    1 gives best speed, 9 gives best compression, 0 gives no compression at all
       
   257    (the input data is simply copied a block at a time).  Z_DEFAULT_COMPRESSION
       
   258    requests a default compromise between speed and compression (currently
       
   259    equivalent to level 6).
       
   260 
       
   261      deflateInit returns Z_OK if success, Z_MEM_ERROR if there was not enough
       
   262    memory, Z_STREAM_ERROR if level is not a valid compression level, or
       
   263    Z_VERSION_ERROR if the zlib library version (zlib_version) is incompatible
       
   264    with the version assumed by the caller (ZLIB_VERSION).  msg is set to null
       
   265    if there is no error message.  deflateInit does not perform any compression:
       
   266    this will be done by deflate().
       
   267 */
       
   268 
       
   269 
       
   270 ZEXTERN int ZEXPORT deflate OF((z_streamp strm, int flush));
       
   271 /*
       
   272     deflate compresses as much data as possible, and stops when the input
       
   273   buffer becomes empty or the output buffer becomes full.  It may introduce
       
   274   some output latency (reading input without producing any output) except when
       
   275   forced to flush.
       
   276 
       
   277     The detailed semantics are as follows.  deflate performs one or both of the
       
   278   following actions:
       
   279 
       
   280   - Compress more input starting at next_in and update next_in and avail_in
       
   281     accordingly.  If not all input can be processed (because there is not
       
   282     enough room in the output buffer), next_in and avail_in are updated and
       
   283     processing will resume at this point for the next call of deflate().
       
   284 
       
   285   - Provide more output starting at next_out and update next_out and avail_out
       
   286     accordingly.  This action is forced if the parameter flush is non zero.
       
   287     Forcing flush frequently degrades the compression ratio, so this parameter
       
   288     should be set only when necessary (in interactive applications).  Some
       
   289     output may be provided even if flush is not set.
       
   290 
       
   291     Before the call of deflate(), the application should ensure that at least
       
   292   one of the actions is possible, by providing more input and/or consuming more
       
   293   output, and updating avail_in or avail_out accordingly; avail_out should
       
   294   never be zero before the call.  The application can consume the compressed
       
   295   output when it wants, for example when the output buffer is full (avail_out
       
   296   == 0), or after each call of deflate().  If deflate returns Z_OK and with
       
   297   zero avail_out, it must be called again after making room in the output
       
   298   buffer because there might be more output pending.
       
   299 
       
   300     Normally the parameter flush is set to Z_NO_FLUSH, which allows deflate to
       
   301   decide how much data to accumulate before producing output, in order to
       
   302   maximize compression.
       
   303 
       
   304     If the parameter flush is set to Z_SYNC_FLUSH, all pending output is
       
   305   flushed to the output buffer and the output is aligned on a byte boundary, so
       
   306   that the decompressor can get all input data available so far.  (In
       
   307   particular avail_in is zero after the call if enough output space has been
       
   308   provided before the call.) Flushing may degrade compression for some
       
   309   compression algorithms and so it should be used only when necessary.  This
       
   310   completes the current deflate block and follows it with an empty stored block
       
   311   that is three bits plus filler bits to the next byte, followed by four bytes
       
   312   (00 00 ff ff).
       
   313 
       
   314     If flush is set to Z_PARTIAL_FLUSH, all pending output is flushed to the
       
   315   output buffer, but the output is not aligned to a byte boundary.  All of the
       
   316   input data so far will be available to the decompressor, as for Z_SYNC_FLUSH.
       
   317   This completes the current deflate block and follows it with an empty fixed
       
   318   codes block that is 10 bits long.  This assures that enough bytes are output
       
   319   in order for the decompressor to finish the block before the empty fixed code
       
   320   block.
       
   321 
       
   322     If flush is set to Z_BLOCK, a deflate block is completed and emitted, as
       
   323   for Z_SYNC_FLUSH, but the output is not aligned on a byte boundary, and up to
       
   324   seven bits of the current block are held to be written as the next byte after
       
   325   the next deflate block is completed.  In this case, the decompressor may not
       
   326   be provided enough bits at this point in order to complete decompression of
       
   327   the data provided so far to the compressor.  It may need to wait for the next
       
   328   block to be emitted.  This is for advanced applications that need to control
       
   329   the emission of deflate blocks.
       
   330 
       
   331     If flush is set to Z_FULL_FLUSH, all output is flushed as with
       
   332   Z_SYNC_FLUSH, and the compression state is reset so that decompression can
       
   333   restart from this point if previous compressed data has been damaged or if
       
   334   random access is desired.  Using Z_FULL_FLUSH too often can seriously degrade
       
   335   compression.
       
   336 
       
   337     If deflate returns with avail_out == 0, this function must be called again
       
   338   with the same value of the flush parameter and more output space (updated
       
   339   avail_out), until the flush is complete (deflate returns with non-zero
       
   340   avail_out).  In the case of a Z_FULL_FLUSH or Z_SYNC_FLUSH, make sure that
       
   341   avail_out is greater than six to avoid repeated flush markers due to
       
   342   avail_out == 0 on return.
       
   343 
       
   344     If the parameter flush is set to Z_FINISH, pending input is processed,
       
   345   pending output is flushed and deflate returns with Z_STREAM_END if there was
       
   346   enough output space; if deflate returns with Z_OK, this function must be
       
   347   called again with Z_FINISH and more output space (updated avail_out) but no
       
   348   more input data, until it returns with Z_STREAM_END or an error.  After
       
   349   deflate has returned Z_STREAM_END, the only possible operations on the stream
       
   350   are deflateReset or deflateEnd.
       
   351 
       
   352     Z_FINISH can be used immediately after deflateInit if all the compression
       
   353   is to be done in a single step.  In this case, avail_out must be at least the
       
   354   value returned by deflateBound (see below).  Then deflate is guaranteed to
       
   355   return Z_STREAM_END.  If not enough output space is provided, deflate will
       
   356   not return Z_STREAM_END, and it must be called again as described above.
       
   357 
       
   358     deflate() sets strm->adler to the adler32 checksum of all input read
       
   359   so far (that is, total_in bytes).
       
   360 
       
   361     deflate() may update strm->data_type if it can make a good guess about
       
   362   the input data type (Z_BINARY or Z_TEXT).  In doubt, the data is considered
       
   363   binary.  This field is only for information purposes and does not affect the
       
   364   compression algorithm in any manner.
       
   365 
       
   366     deflate() returns Z_OK if some progress has been made (more input
       
   367   processed or more output produced), Z_STREAM_END if all input has been
       
   368   consumed and all output has been produced (only when flush is set to
       
   369   Z_FINISH), Z_STREAM_ERROR if the stream state was inconsistent (for example
       
   370   if next_in or next_out was Z_NULL), Z_BUF_ERROR if no progress is possible
       
   371   (for example avail_in or avail_out was zero).  Note that Z_BUF_ERROR is not
       
   372   fatal, and deflate() can be called again with more input and more output
       
   373   space to continue compressing.
       
   374 */
       
   375 
       
   376 
       
   377 ZEXTERN int ZEXPORT deflateEnd OF((z_streamp strm));
       
   378 /*
       
   379      All dynamically allocated data structures for this stream are freed.
       
   380    This function discards any unprocessed input and does not flush any pending
       
   381    output.
       
   382 
       
   383      deflateEnd returns Z_OK if success, Z_STREAM_ERROR if the
       
   384    stream state was inconsistent, Z_DATA_ERROR if the stream was freed
       
   385    prematurely (some input or output was discarded).  In the error case, msg
       
   386    may be set but then points to a static string (which must not be
       
   387    deallocated).
       
   388 */
       
   389 
       
   390 
       
   391 /*
       
   392 ZEXTERN int ZEXPORT inflateInit OF((z_streamp strm));
       
   393 
       
   394      Initializes the internal stream state for decompression.  The fields
       
   395    next_in, avail_in, zalloc, zfree and opaque must be initialized before by
       
   396    the caller.  If next_in is not Z_NULL and avail_in is large enough (the
       
   397    exact value depends on the compression method), inflateInit determines the
       
   398    compression method from the zlib header and allocates all data structures
       
   399    accordingly; otherwise the allocation will be deferred to the first call of
       
   400    inflate.  If zalloc and zfree are set to Z_NULL, inflateInit updates them to
       
   401    use default allocation functions.
       
   402 
       
   403      inflateInit returns Z_OK if success, Z_MEM_ERROR if there was not enough
       
   404    memory, Z_VERSION_ERROR if the zlib library version is incompatible with the
       
   405    version assumed by the caller, or Z_STREAM_ERROR if the parameters are
       
   406    invalid, such as a null pointer to the structure.  msg is set to null if
       
   407    there is no error message.  inflateInit does not perform any decompression
       
   408    apart from possibly reading the zlib header if present: actual decompression
       
   409    will be done by inflate().  (So next_in and avail_in may be modified, but
       
   410    next_out and avail_out are unused and unchanged.) The current implementation
       
   411    of inflateInit() does not process any header information -- that is deferred
       
   412    until inflate() is called.
       
   413 */
       
   414 
       
   415 
       
   416 ZEXTERN int ZEXPORT inflate OF((z_streamp strm, int flush));
       
   417 /*
       
   418     inflate decompresses as much data as possible, and stops when the input
       
   419   buffer becomes empty or the output buffer becomes full.  It may introduce
       
   420   some output latency (reading input without producing any output) except when
       
   421   forced to flush.
       
   422 
       
   423   The detailed semantics are as follows.  inflate performs one or both of the
       
   424   following actions:
       
   425 
       
   426   - Decompress more input starting at next_in and update next_in and avail_in
       
   427     accordingly.  If not all input can be processed (because there is not
       
   428     enough room in the output buffer), next_in is updated and processing will
       
   429     resume at this point for the next call of inflate().
       
   430 
       
   431   - Provide more output starting at next_out and update next_out and avail_out
       
   432     accordingly.  inflate() provides as much output as possible, until there is
       
   433     no more input data or no more space in the output buffer (see below about
       
   434     the flush parameter).
       
   435 
       
   436     Before the call of inflate(), the application should ensure that at least
       
   437   one of the actions is possible, by providing more input and/or consuming more
       
   438   output, and updating the next_* and avail_* values accordingly.  The
       
   439   application can consume the uncompressed output when it wants, for example
       
   440   when the output buffer is full (avail_out == 0), or after each call of
       
   441   inflate().  If inflate returns Z_OK and with zero avail_out, it must be
       
   442   called again after making room in the output buffer because there might be
       
   443   more output pending.
       
   444 
       
   445     The flush parameter of inflate() can be Z_NO_FLUSH, Z_SYNC_FLUSH, Z_FINISH,
       
   446   Z_BLOCK, or Z_TREES.  Z_SYNC_FLUSH requests that inflate() flush as much
       
   447   output as possible to the output buffer.  Z_BLOCK requests that inflate()
       
   448   stop if and when it gets to the next deflate block boundary.  When decoding
       
   449   the zlib or gzip format, this will cause inflate() to return immediately
       
   450   after the header and before the first block.  When doing a raw inflate,
       
   451   inflate() will go ahead and process the first block, and will return when it
       
   452   gets to the end of that block, or when it runs out of data.
       
   453 
       
   454     The Z_BLOCK option assists in appending to or combining deflate streams.
       
   455   Also to assist in this, on return inflate() will set strm->data_type to the
       
   456   number of unused bits in the last byte taken from strm->next_in, plus 64 if
       
   457   inflate() is currently decoding the last block in the deflate stream, plus
       
   458   128 if inflate() returned immediately after decoding an end-of-block code or
       
   459   decoding the complete header up to just before the first byte of the deflate
       
   460   stream.  The end-of-block will not be indicated until all of the uncompressed
       
   461   data from that block has been written to strm->next_out.  The number of
       
   462   unused bits may in general be greater than seven, except when bit 7 of
       
   463   data_type is set, in which case the number of unused bits will be less than
       
   464   eight.  data_type is set as noted here every time inflate() returns for all
       
   465   flush options, and so can be used to determine the amount of currently
       
   466   consumed input in bits.
       
   467 
       
   468     The Z_TREES option behaves as Z_BLOCK does, but it also returns when the
       
   469   end of each deflate block header is reached, before any actual data in that
       
   470   block is decoded.  This allows the caller to determine the length of the
       
   471   deflate block header for later use in random access within a deflate block.
       
   472   256 is added to the value of strm->data_type when inflate() returns
       
   473   immediately after reaching the end of the deflate block header.
       
   474 
       
   475     inflate() should normally be called until it returns Z_STREAM_END or an
       
   476   error.  However if all decompression is to be performed in a single step (a
       
   477   single call of inflate), the parameter flush should be set to Z_FINISH.  In
       
   478   this case all pending input is processed and all pending output is flushed;
       
   479   avail_out must be large enough to hold all of the uncompressed data for the
       
   480   operation to complete.  (The size of the uncompressed data may have been
       
   481   saved by the compressor for this purpose.) The use of Z_FINISH is not
       
   482   required to perform an inflation in one step.  However it may be used to
       
   483   inform inflate that a faster approach can be used for the single inflate()
       
   484   call.  Z_FINISH also informs inflate to not maintain a sliding window if the
       
   485   stream completes, which reduces inflate's memory footprint.  If the stream
       
   486   does not complete, either because not all of the stream is provided or not
       
   487   enough output space is provided, then a sliding window will be allocated and
       
   488   inflate() can be called again to continue the operation as if Z_NO_FLUSH had
       
   489   been used.
       
   490 
       
   491      In this implementation, inflate() always flushes as much output as
       
   492   possible to the output buffer, and always uses the faster approach on the
       
   493   first call.  So the effects of the flush parameter in this implementation are
       
   494   on the return value of inflate() as noted below, when inflate() returns early
       
   495   when Z_BLOCK or Z_TREES is used, and when inflate() avoids the allocation of
       
   496   memory for a sliding window when Z_FINISH is used.
       
   497 
       
   498      If a preset dictionary is needed after this call (see inflateSetDictionary
       
   499   below), inflate sets strm->adler to the Adler-32 checksum of the dictionary
       
   500   chosen by the compressor and returns Z_NEED_DICT; otherwise it sets
       
   501   strm->adler to the Adler-32 checksum of all output produced so far (that is,
       
   502   total_out bytes) and returns Z_OK, Z_STREAM_END or an error code as described
       
   503   below.  At the end of the stream, inflate() checks that its computed adler32
       
   504   checksum is equal to that saved by the compressor and returns Z_STREAM_END
       
   505   only if the checksum is correct.
       
   506 
       
   507     inflate() can decompress and check either zlib-wrapped or gzip-wrapped
       
   508   deflate data.  The header type is detected automatically, if requested when
       
   509   initializing with inflateInit2().  Any information contained in the gzip
       
   510   header is not retained, so applications that need that information should
       
   511   instead use raw inflate, see inflateInit2() below, or inflateBack() and
       
   512   perform their own processing of the gzip header and trailer.  When processing
       
   513   gzip-wrapped deflate data, strm->adler32 is set to the CRC-32 of the output
       
   514   producted so far.  The CRC-32 is checked against the gzip trailer.
       
   515 
       
   516     inflate() returns Z_OK if some progress has been made (more input processed
       
   517   or more output produced), Z_STREAM_END if the end of the compressed data has
       
   518   been reached and all uncompressed output has been produced, Z_NEED_DICT if a
       
   519   preset dictionary is needed at this point, Z_DATA_ERROR if the input data was
       
   520   corrupted (input stream not conforming to the zlib format or incorrect check
       
   521   value), Z_STREAM_ERROR if the stream structure was inconsistent (for example
       
   522   next_in or next_out was Z_NULL), Z_MEM_ERROR if there was not enough memory,
       
   523   Z_BUF_ERROR if no progress is possible or if there was not enough room in the
       
   524   output buffer when Z_FINISH is used.  Note that Z_BUF_ERROR is not fatal, and
       
   525   inflate() can be called again with more input and more output space to
       
   526   continue decompressing.  If Z_DATA_ERROR is returned, the application may
       
   527   then call inflateSync() to look for a good compression block if a partial
       
   528   recovery of the data is desired.
       
   529 */
       
   530 
       
   531 
       
   532 ZEXTERN int ZEXPORT inflateEnd OF((z_streamp strm));
       
   533 /*
       
   534      All dynamically allocated data structures for this stream are freed.
       
   535    This function discards any unprocessed input and does not flush any pending
       
   536    output.
       
   537 
       
   538      inflateEnd returns Z_OK if success, Z_STREAM_ERROR if the stream state
       
   539    was inconsistent.  In the error case, msg may be set but then points to a
       
   540    static string (which must not be deallocated).
       
   541 */
       
   542 
       
   543 
       
   544                         /* Advanced functions */
       
   545 
       
   546 /*
       
   547     The following functions are needed only in some special applications.
       
   548 */
       
   549 
       
   550 /*
       
   551 ZEXTERN int ZEXPORT deflateInit2 OF((z_streamp strm,
       
   552                                      int  level,
       
   553                                      int  method,
       
   554                                      int  windowBits,
       
   555                                      int  memLevel,
       
   556                                      int  strategy));
       
   557 
       
   558      This is another version of deflateInit with more compression options.  The
       
   559    fields next_in, zalloc, zfree and opaque must be initialized before by the
       
   560    caller.
       
   561 
       
   562      The method parameter is the compression method.  It must be Z_DEFLATED in
       
   563    this version of the library.
       
   564 
       
   565      The windowBits parameter is the base two logarithm of the window size
       
   566    (the size of the history buffer).  It should be in the range 8..15 for this
       
   567    version of the library.  Larger values of this parameter result in better
       
   568    compression at the expense of memory usage.  The default value is 15 if
       
   569    deflateInit is used instead.
       
   570 
       
   571      windowBits can also be -8..-15 for raw deflate.  In this case, -windowBits
       
   572    determines the window size.  deflate() will then generate raw deflate data
       
   573    with no zlib header or trailer, and will not compute an adler32 check value.
       
   574 
       
   575      windowBits can also be greater than 15 for optional gzip encoding.  Add
       
   576    16 to windowBits to write a simple gzip header and trailer around the
       
   577    compressed data instead of a zlib wrapper.  The gzip header will have no
       
   578    file name, no extra data, no comment, no modification time (set to zero), no
       
   579    header crc, and the operating system will be set to 255 (unknown).  If a
       
   580    gzip stream is being written, strm->adler is a crc32 instead of an adler32.
       
   581 
       
   582      The memLevel parameter specifies how much memory should be allocated
       
   583    for the internal compression state.  memLevel=1 uses minimum memory but is
       
   584    slow and reduces compression ratio; memLevel=9 uses maximum memory for
       
   585    optimal speed.  The default value is 8.  See zconf.h for total memory usage
       
   586    as a function of windowBits and memLevel.
       
   587 
       
   588      The strategy parameter is used to tune the compression algorithm.  Use the
       
   589    value Z_DEFAULT_STRATEGY for normal data, Z_FILTERED for data produced by a
       
   590    filter (or predictor), Z_HUFFMAN_ONLY to force Huffman encoding only (no
       
   591    string match), or Z_RLE to limit match distances to one (run-length
       
   592    encoding).  Filtered data consists mostly of small values with a somewhat
       
   593    random distribution.  In this case, the compression algorithm is tuned to
       
   594    compress them better.  The effect of Z_FILTERED is to force more Huffman
       
   595    coding and less string matching; it is somewhat intermediate between
       
   596    Z_DEFAULT_STRATEGY and Z_HUFFMAN_ONLY.  Z_RLE is designed to be almost as
       
   597    fast as Z_HUFFMAN_ONLY, but give better compression for PNG image data.  The
       
   598    strategy parameter only affects the compression ratio but not the
       
   599    correctness of the compressed output even if it is not set appropriately.
       
   600    Z_FIXED prevents the use of dynamic Huffman codes, allowing for a simpler
       
   601    decoder for special applications.
       
   602 
       
   603      deflateInit2 returns Z_OK if success, Z_MEM_ERROR if there was not enough
       
   604    memory, Z_STREAM_ERROR if any parameter is invalid (such as an invalid
       
   605    method), or Z_VERSION_ERROR if the zlib library version (zlib_version) is
       
   606    incompatible with the version assumed by the caller (ZLIB_VERSION).  msg is
       
   607    set to null if there is no error message.  deflateInit2 does not perform any
       
   608    compression: this will be done by deflate().
       
   609 */
       
   610 
       
   611 ZEXTERN int ZEXPORT deflateSetDictionary OF((z_streamp strm,
       
   612                                              const Bytef *dictionary,
       
   613                                              uInt  dictLength));
       
   614 /*
       
   615      Initializes the compression dictionary from the given byte sequence
       
   616    without producing any compressed output.  When using the zlib format, this
       
   617    function must be called immediately after deflateInit, deflateInit2 or
       
   618    deflateReset, and before any call of deflate.  When doing raw deflate, this
       
   619    function must be called either before any call of deflate, or immediately
       
   620    after the completion of a deflate block, i.e. after all input has been
       
   621    consumed and all output has been delivered when using any of the flush
       
   622    options Z_BLOCK, Z_PARTIAL_FLUSH, Z_SYNC_FLUSH, or Z_FULL_FLUSH.  The
       
   623    compressor and decompressor must use exactly the same dictionary (see
       
   624    inflateSetDictionary).
       
   625 
       
   626      The dictionary should consist of strings (byte sequences) that are likely
       
   627    to be encountered later in the data to be compressed, with the most commonly
       
   628    used strings preferably put towards the end of the dictionary.  Using a
       
   629    dictionary is most useful when the data to be compressed is short and can be
       
   630    predicted with good accuracy; the data can then be compressed better than
       
   631    with the default empty dictionary.
       
   632 
       
   633      Depending on the size of the compression data structures selected by
       
   634    deflateInit or deflateInit2, a part of the dictionary may in effect be
       
   635    discarded, for example if the dictionary is larger than the window size
       
   636    provided in deflateInit or deflateInit2.  Thus the strings most likely to be
       
   637    useful should be put at the end of the dictionary, not at the front.  In
       
   638    addition, the current implementation of deflate will use at most the window
       
   639    size minus 262 bytes of the provided dictionary.
       
   640 
       
   641      Upon return of this function, strm->adler is set to the adler32 value
       
   642    of the dictionary; the decompressor may later use this value to determine
       
   643    which dictionary has been used by the compressor.  (The adler32 value
       
   644    applies to the whole dictionary even if only a subset of the dictionary is
       
   645    actually used by the compressor.) If a raw deflate was requested, then the
       
   646    adler32 value is not computed and strm->adler is not set.
       
   647 
       
   648      deflateSetDictionary returns Z_OK if success, or Z_STREAM_ERROR if a
       
   649    parameter is invalid (e.g.  dictionary being Z_NULL) or the stream state is
       
   650    inconsistent (for example if deflate has already been called for this stream
       
   651    or if not at a block boundary for raw deflate).  deflateSetDictionary does
       
   652    not perform any compression: this will be done by deflate().
       
   653 */
       
   654 
       
   655 ZEXTERN int ZEXPORT deflateCopy OF((z_streamp dest,
       
   656                                     z_streamp source));
       
   657 /*
       
   658      Sets the destination stream as a complete copy of the source stream.
       
   659 
       
   660      This function can be useful when several compression strategies will be
       
   661    tried, for example when there are several ways of pre-processing the input
       
   662    data with a filter.  The streams that will be discarded should then be freed
       
   663    by calling deflateEnd.  Note that deflateCopy duplicates the internal
       
   664    compression state which can be quite large, so this strategy is slow and can
       
   665    consume lots of memory.
       
   666 
       
   667      deflateCopy returns Z_OK if success, Z_MEM_ERROR if there was not
       
   668    enough memory, Z_STREAM_ERROR if the source stream state was inconsistent
       
   669    (such as zalloc being Z_NULL).  msg is left unchanged in both source and
       
   670    destination.
       
   671 */
       
   672 
       
   673 ZEXTERN int ZEXPORT deflateReset OF((z_streamp strm));
       
   674 /*
       
   675      This function is equivalent to deflateEnd followed by deflateInit,
       
   676    but does not free and reallocate all the internal compression state.  The
       
   677    stream will keep the same compression level and any other attributes that
       
   678    may have been set by deflateInit2.
       
   679 
       
   680      deflateReset returns Z_OK if success, or Z_STREAM_ERROR if the source
       
   681    stream state was inconsistent (such as zalloc or state being Z_NULL).
       
   682 */
       
   683 
       
   684 ZEXTERN int ZEXPORT deflateParams OF((z_streamp strm,
       
   685                                       int level,
       
   686                                       int strategy));
       
   687 /*
       
   688      Dynamically update the compression level and compression strategy.  The
       
   689    interpretation of level and strategy is as in deflateInit2.  This can be
       
   690    used to switch between compression and straight copy of the input data, or
       
   691    to switch to a different kind of input data requiring a different strategy.
       
   692    If the compression level is changed, the input available so far is
       
   693    compressed with the old level (and may be flushed); the new level will take
       
   694    effect only at the next call of deflate().
       
   695 
       
   696      Before the call of deflateParams, the stream state must be set as for
       
   697    a call of deflate(), since the currently available input may have to be
       
   698    compressed and flushed.  In particular, strm->avail_out must be non-zero.
       
   699 
       
   700      deflateParams returns Z_OK if success, Z_STREAM_ERROR if the source
       
   701    stream state was inconsistent or if a parameter was invalid, Z_BUF_ERROR if
       
   702    strm->avail_out was zero.
       
   703 */
       
   704 
       
   705 ZEXTERN int ZEXPORT deflateTune OF((z_streamp strm,
       
   706                                     int good_length,
       
   707                                     int max_lazy,
       
   708                                     int nice_length,
       
   709                                     int max_chain));
       
   710 /*
       
   711      Fine tune deflate's internal compression parameters.  This should only be
       
   712    used by someone who understands the algorithm used by zlib's deflate for
       
   713    searching for the best matching string, and even then only by the most
       
   714    fanatic optimizer trying to squeeze out the last compressed bit for their
       
   715    specific input data.  Read the deflate.c source code for the meaning of the
       
   716    max_lazy, good_length, nice_length, and max_chain parameters.
       
   717 
       
   718      deflateTune() can be called after deflateInit() or deflateInit2(), and
       
   719    returns Z_OK on success, or Z_STREAM_ERROR for an invalid deflate stream.
       
   720  */
       
   721 
       
   722 ZEXTERN uLong ZEXPORT deflateBound OF((z_streamp strm,
       
   723                                        uLong sourceLen));
       
   724 /*
       
   725      deflateBound() returns an upper bound on the compressed size after
       
   726    deflation of sourceLen bytes.  It must be called after deflateInit() or
       
   727    deflateInit2(), and after deflateSetHeader(), if used.  This would be used
       
   728    to allocate an output buffer for deflation in a single pass, and so would be
       
   729    called before deflate().  If that first deflate() call is provided the
       
   730    sourceLen input bytes, an output buffer allocated to the size returned by
       
   731    deflateBound(), and the flush value Z_FINISH, then deflate() is guaranteed
       
   732    to return Z_STREAM_END.  Note that it is possible for the compressed size to
       
   733    be larger than the value returned by deflateBound() if flush options other
       
   734    than Z_FINISH or Z_NO_FLUSH are used.
       
   735 */
       
   736 
       
   737 ZEXTERN int ZEXPORT deflatePending OF((z_streamp strm,
       
   738                                        unsigned *pending,
       
   739                                        int *bits));
       
   740 /*
       
   741      deflatePending() returns the number of bytes and bits of output that have
       
   742    been generated, but not yet provided in the available output.  The bytes not
       
   743    provided would be due to the available output space having being consumed.
       
   744    The number of bits of output not provided are between 0 and 7, where they
       
   745    await more bits to join them in order to fill out a full byte.  If pending
       
   746    or bits are Z_NULL, then those values are not set.
       
   747 
       
   748      deflatePending returns Z_OK if success, or Z_STREAM_ERROR if the source
       
   749    stream state was inconsistent.
       
   750  */
       
   751 
       
   752 ZEXTERN int ZEXPORT deflatePrime OF((z_streamp strm,
       
   753                                      int bits,
       
   754                                      int value));
       
   755 /*
       
   756      deflatePrime() inserts bits in the deflate output stream.  The intent
       
   757    is that this function is used to start off the deflate output with the bits
       
   758    leftover from a previous deflate stream when appending to it.  As such, this
       
   759    function can only be used for raw deflate, and must be used before the first
       
   760    deflate() call after a deflateInit2() or deflateReset().  bits must be less
       
   761    than or equal to 16, and that many of the least significant bits of value
       
   762    will be inserted in the output.
       
   763 
       
   764      deflatePrime returns Z_OK if success, Z_BUF_ERROR if there was not enough
       
   765    room in the internal buffer to insert the bits, or Z_STREAM_ERROR if the
       
   766    source stream state was inconsistent.
       
   767 */
       
   768 
       
   769 ZEXTERN int ZEXPORT deflateSetHeader OF((z_streamp strm,
       
   770                                          gz_headerp head));
       
   771 /*
       
   772      deflateSetHeader() provides gzip header information for when a gzip
       
   773    stream is requested by deflateInit2().  deflateSetHeader() may be called
       
   774    after deflateInit2() or deflateReset() and before the first call of
       
   775    deflate().  The text, time, os, extra field, name, and comment information
       
   776    in the provided gz_header structure are written to the gzip header (xflag is
       
   777    ignored -- the extra flags are set according to the compression level).  The
       
   778    caller must assure that, if not Z_NULL, name and comment are terminated with
       
   779    a zero byte, and that if extra is not Z_NULL, that extra_len bytes are
       
   780    available there.  If hcrc is true, a gzip header crc is included.  Note that
       
   781    the current versions of the command-line version of gzip (up through version
       
   782    1.3.x) do not support header crc's, and will report that it is a "multi-part
       
   783    gzip file" and give up.
       
   784 
       
   785      If deflateSetHeader is not used, the default gzip header has text false,
       
   786    the time set to zero, and os set to 255, with no extra, name, or comment
       
   787    fields.  The gzip header is returned to the default state by deflateReset().
       
   788 
       
   789      deflateSetHeader returns Z_OK if success, or Z_STREAM_ERROR if the source
       
   790    stream state was inconsistent.
       
   791 */
       
   792 
       
   793 /*
       
   794 ZEXTERN int ZEXPORT inflateInit2 OF((z_streamp strm,
       
   795                                      int  windowBits));
       
   796 
       
   797      This is another version of inflateInit with an extra parameter.  The
       
   798    fields next_in, avail_in, zalloc, zfree and opaque must be initialized
       
   799    before by the caller.
       
   800 
       
   801      The windowBits parameter is the base two logarithm of the maximum window
       
   802    size (the size of the history buffer).  It should be in the range 8..15 for
       
   803    this version of the library.  The default value is 15 if inflateInit is used
       
   804    instead.  windowBits must be greater than or equal to the windowBits value
       
   805    provided to deflateInit2() while compressing, or it must be equal to 15 if
       
   806    deflateInit2() was not used.  If a compressed stream with a larger window
       
   807    size is given as input, inflate() will return with the error code
       
   808    Z_DATA_ERROR instead of trying to allocate a larger window.
       
   809 
       
   810      windowBits can also be zero to request that inflate use the window size in
       
   811    the zlib header of the compressed stream.
       
   812 
       
   813      windowBits can also be -8..-15 for raw inflate.  In this case, -windowBits
       
   814    determines the window size.  inflate() will then process raw deflate data,
       
   815    not looking for a zlib or gzip header, not generating a check value, and not
       
   816    looking for any check values for comparison at the end of the stream.  This
       
   817    is for use with other formats that use the deflate compressed data format
       
   818    such as zip.  Those formats provide their own check values.  If a custom
       
   819    format is developed using the raw deflate format for compressed data, it is
       
   820    recommended that a check value such as an adler32 or a crc32 be applied to
       
   821    the uncompressed data as is done in the zlib, gzip, and zip formats.  For
       
   822    most applications, the zlib format should be used as is.  Note that comments
       
   823    above on the use in deflateInit2() applies to the magnitude of windowBits.
       
   824 
       
   825      windowBits can also be greater than 15 for optional gzip decoding.  Add
       
   826    32 to windowBits to enable zlib and gzip decoding with automatic header
       
   827    detection, or add 16 to decode only the gzip format (the zlib format will
       
   828    return a Z_DATA_ERROR).  If a gzip stream is being decoded, strm->adler is a
       
   829    crc32 instead of an adler32.
       
   830 
       
   831      inflateInit2 returns Z_OK if success, Z_MEM_ERROR if there was not enough
       
   832    memory, Z_VERSION_ERROR if the zlib library version is incompatible with the
       
   833    version assumed by the caller, or Z_STREAM_ERROR if the parameters are
       
   834    invalid, such as a null pointer to the structure.  msg is set to null if
       
   835    there is no error message.  inflateInit2 does not perform any decompression
       
   836    apart from possibly reading the zlib header if present: actual decompression
       
   837    will be done by inflate().  (So next_in and avail_in may be modified, but
       
   838    next_out and avail_out are unused and unchanged.) The current implementation
       
   839    of inflateInit2() does not process any header information -- that is
       
   840    deferred until inflate() is called.
       
   841 */
       
   842 
       
   843 ZEXTERN int ZEXPORT inflateSetDictionary OF((z_streamp strm,
       
   844                                              const Bytef *dictionary,
       
   845                                              uInt  dictLength));
       
   846 /*
       
   847      Initializes the decompression dictionary from the given uncompressed byte
       
   848    sequence.  This function must be called immediately after a call of inflate,
       
   849    if that call returned Z_NEED_DICT.  The dictionary chosen by the compressor
       
   850    can be determined from the adler32 value returned by that call of inflate.
       
   851    The compressor and decompressor must use exactly the same dictionary (see
       
   852    deflateSetDictionary).  For raw inflate, this function can be called at any
       
   853    time to set the dictionary.  If the provided dictionary is smaller than the
       
   854    window and there is already data in the window, then the provided dictionary
       
   855    will amend what's there.  The application must insure that the dictionary
       
   856    that was used for compression is provided.
       
   857 
       
   858      inflateSetDictionary returns Z_OK if success, Z_STREAM_ERROR if a
       
   859    parameter is invalid (e.g.  dictionary being Z_NULL) or the stream state is
       
   860    inconsistent, Z_DATA_ERROR if the given dictionary doesn't match the
       
   861    expected one (incorrect adler32 value).  inflateSetDictionary does not
       
   862    perform any decompression: this will be done by subsequent calls of
       
   863    inflate().
       
   864 */
       
   865 
       
   866 ZEXTERN int ZEXPORT inflateGetDictionary OF((z_streamp strm,
       
   867                                              Bytef *dictionary,
       
   868                                              uInt  *dictLength));
       
   869 /*
       
   870      Returns the sliding dictionary being maintained by inflate.  dictLength is
       
   871    set to the number of bytes in the dictionary, and that many bytes are copied
       
   872    to dictionary.  dictionary must have enough space, where 32768 bytes is
       
   873    always enough.  If inflateGetDictionary() is called with dictionary equal to
       
   874    Z_NULL, then only the dictionary length is returned, and nothing is copied.
       
   875    Similary, if dictLength is Z_NULL, then it is not set.
       
   876 
       
   877      inflateGetDictionary returns Z_OK on success, or Z_STREAM_ERROR if the
       
   878    stream state is inconsistent.
       
   879 */
       
   880 
       
   881 ZEXTERN int ZEXPORT inflateSync OF((z_streamp strm));
       
   882 /*
       
   883      Skips invalid compressed data until a possible full flush point (see above
       
   884    for the description of deflate with Z_FULL_FLUSH) can be found, or until all
       
   885    available input is skipped.  No output is provided.
       
   886 
       
   887      inflateSync searches for a 00 00 FF FF pattern in the compressed data.
       
   888    All full flush points have this pattern, but not all occurrences of this
       
   889    pattern are full flush points.
       
   890 
       
   891      inflateSync returns Z_OK if a possible full flush point has been found,
       
   892    Z_BUF_ERROR if no more input was provided, Z_DATA_ERROR if no flush point
       
   893    has been found, or Z_STREAM_ERROR if the stream structure was inconsistent.
       
   894    In the success case, the application may save the current current value of
       
   895    total_in which indicates where valid compressed data was found.  In the
       
   896    error case, the application may repeatedly call inflateSync, providing more
       
   897    input each time, until success or end of the input data.
       
   898 */
       
   899 
       
   900 ZEXTERN int ZEXPORT inflateCopy OF((z_streamp dest,
       
   901                                     z_streamp source));
       
   902 /*
       
   903      Sets the destination stream as a complete copy of the source stream.
       
   904 
       
   905      This function can be useful when randomly accessing a large stream.  The
       
   906    first pass through the stream can periodically record the inflate state,
       
   907    allowing restarting inflate at those points when randomly accessing the
       
   908    stream.
       
   909 
       
   910      inflateCopy returns Z_OK if success, Z_MEM_ERROR if there was not
       
   911    enough memory, Z_STREAM_ERROR if the source stream state was inconsistent
       
   912    (such as zalloc being Z_NULL).  msg is left unchanged in both source and
       
   913    destination.
       
   914 */
       
   915 
       
   916 ZEXTERN int ZEXPORT inflateReset OF((z_streamp strm));
       
   917 /*
       
   918      This function is equivalent to inflateEnd followed by inflateInit,
       
   919    but does not free and reallocate all the internal decompression state.  The
       
   920    stream will keep attributes that may have been set by inflateInit2.
       
   921 
       
   922      inflateReset returns Z_OK if success, or Z_STREAM_ERROR if the source
       
   923    stream state was inconsistent (such as zalloc or state being Z_NULL).
       
   924 */
       
   925 
       
   926 ZEXTERN int ZEXPORT inflateReset2 OF((z_streamp strm,
       
   927                                       int windowBits));
       
   928 /*
       
   929      This function is the same as inflateReset, but it also permits changing
       
   930    the wrap and window size requests.  The windowBits parameter is interpreted
       
   931    the same as it is for inflateInit2.
       
   932 
       
   933      inflateReset2 returns Z_OK if success, or Z_STREAM_ERROR if the source
       
   934    stream state was inconsistent (such as zalloc or state being Z_NULL), or if
       
   935    the windowBits parameter is invalid.
       
   936 */
       
   937 
       
   938 ZEXTERN int ZEXPORT inflatePrime OF((z_streamp strm,
       
   939                                      int bits,
       
   940                                      int value));
       
   941 /*
       
   942      This function inserts bits in the inflate input stream.  The intent is
       
   943    that this function is used to start inflating at a bit position in the
       
   944    middle of a byte.  The provided bits will be used before any bytes are used
       
   945    from next_in.  This function should only be used with raw inflate, and
       
   946    should be used before the first inflate() call after inflateInit2() or
       
   947    inflateReset().  bits must be less than or equal to 16, and that many of the
       
   948    least significant bits of value will be inserted in the input.
       
   949 
       
   950      If bits is negative, then the input stream bit buffer is emptied.  Then
       
   951    inflatePrime() can be called again to put bits in the buffer.  This is used
       
   952    to clear out bits leftover after feeding inflate a block description prior
       
   953    to feeding inflate codes.
       
   954 
       
   955      inflatePrime returns Z_OK if success, or Z_STREAM_ERROR if the source
       
   956    stream state was inconsistent.
       
   957 */
       
   958 
       
   959 ZEXTERN long ZEXPORT inflateMark OF((z_streamp strm));
       
   960 /*
       
   961      This function returns two values, one in the lower 16 bits of the return
       
   962    value, and the other in the remaining upper bits, obtained by shifting the
       
   963    return value down 16 bits.  If the upper value is -1 and the lower value is
       
   964    zero, then inflate() is currently decoding information outside of a block.
       
   965    If the upper value is -1 and the lower value is non-zero, then inflate is in
       
   966    the middle of a stored block, with the lower value equaling the number of
       
   967    bytes from the input remaining to copy.  If the upper value is not -1, then
       
   968    it is the number of bits back from the current bit position in the input of
       
   969    the code (literal or length/distance pair) currently being processed.  In
       
   970    that case the lower value is the number of bytes already emitted for that
       
   971    code.
       
   972 
       
   973      A code is being processed if inflate is waiting for more input to complete
       
   974    decoding of the code, or if it has completed decoding but is waiting for
       
   975    more output space to write the literal or match data.
       
   976 
       
   977      inflateMark() is used to mark locations in the input data for random
       
   978    access, which may be at bit positions, and to note those cases where the
       
   979    output of a code may span boundaries of random access blocks.  The current
       
   980    location in the input stream can be determined from avail_in and data_type
       
   981    as noted in the description for the Z_BLOCK flush parameter for inflate.
       
   982 
       
   983      inflateMark returns the value noted above or -1 << 16 if the provided
       
   984    source stream state was inconsistent.
       
   985 */
       
   986 
       
   987 ZEXTERN int ZEXPORT inflateGetHeader OF((z_streamp strm,
       
   988                                          gz_headerp head));
       
   989 /*
       
   990      inflateGetHeader() requests that gzip header information be stored in the
       
   991    provided gz_header structure.  inflateGetHeader() may be called after
       
   992    inflateInit2() or inflateReset(), and before the first call of inflate().
       
   993    As inflate() processes the gzip stream, head->done is zero until the header
       
   994    is completed, at which time head->done is set to one.  If a zlib stream is
       
   995    being decoded, then head->done is set to -1 to indicate that there will be
       
   996    no gzip header information forthcoming.  Note that Z_BLOCK or Z_TREES can be
       
   997    used to force inflate() to return immediately after header processing is
       
   998    complete and before any actual data is decompressed.
       
   999 
       
  1000      The text, time, xflags, and os fields are filled in with the gzip header
       
  1001    contents.  hcrc is set to true if there is a header CRC.  (The header CRC
       
  1002    was valid if done is set to one.) If extra is not Z_NULL, then extra_max
       
  1003    contains the maximum number of bytes to write to extra.  Once done is true,
       
  1004    extra_len contains the actual extra field length, and extra contains the
       
  1005    extra field, or that field truncated if extra_max is less than extra_len.
       
  1006    If name is not Z_NULL, then up to name_max characters are written there,
       
  1007    terminated with a zero unless the length is greater than name_max.  If
       
  1008    comment is not Z_NULL, then up to comm_max characters are written there,
       
  1009    terminated with a zero unless the length is greater than comm_max.  When any
       
  1010    of extra, name, or comment are not Z_NULL and the respective field is not
       
  1011    present in the header, then that field is set to Z_NULL to signal its
       
  1012    absence.  This allows the use of deflateSetHeader() with the returned
       
  1013    structure to duplicate the header.  However if those fields are set to
       
  1014    allocated memory, then the application will need to save those pointers
       
  1015    elsewhere so that they can be eventually freed.
       
  1016 
       
  1017      If inflateGetHeader is not used, then the header information is simply
       
  1018    discarded.  The header is always checked for validity, including the header
       
  1019    CRC if present.  inflateReset() will reset the process to discard the header
       
  1020    information.  The application would need to call inflateGetHeader() again to
       
  1021    retrieve the header from the next gzip stream.
       
  1022 
       
  1023      inflateGetHeader returns Z_OK if success, or Z_STREAM_ERROR if the source
       
  1024    stream state was inconsistent.
       
  1025 */
       
  1026 
       
  1027 /*
       
  1028 ZEXTERN int ZEXPORT inflateBackInit OF((z_streamp strm, int windowBits,
       
  1029                                         unsigned char FAR *window));
       
  1030 
       
  1031      Initialize the internal stream state for decompression using inflateBack()
       
  1032    calls.  The fields zalloc, zfree and opaque in strm must be initialized
       
  1033    before the call.  If zalloc and zfree are Z_NULL, then the default library-
       
  1034    derived memory allocation routines are used.  windowBits is the base two
       
  1035    logarithm of the window size, in the range 8..15.  window is a caller
       
  1036    supplied buffer of that size.  Except for special applications where it is
       
  1037    assured that deflate was used with small window sizes, windowBits must be 15
       
  1038    and a 32K byte window must be supplied to be able to decompress general
       
  1039    deflate streams.
       
  1040 
       
  1041      See inflateBack() for the usage of these routines.
       
  1042 
       
  1043      inflateBackInit will return Z_OK on success, Z_STREAM_ERROR if any of
       
  1044    the parameters are invalid, Z_MEM_ERROR if the internal state could not be
       
  1045    allocated, or Z_VERSION_ERROR if the version of the library does not match
       
  1046    the version of the header file.
       
  1047 */
       
  1048 
       
  1049 typedef unsigned (*in_func) OF((void FAR *,
       
  1050                                 z_const unsigned char FAR * FAR *));
       
  1051 typedef int (*out_func) OF((void FAR *, unsigned char FAR *, unsigned));
       
  1052 
       
  1053 ZEXTERN int ZEXPORT inflateBack OF((z_streamp strm,
       
  1054                                     in_func in, void FAR *in_desc,
       
  1055                                     out_func out, void FAR *out_desc));
       
  1056 /*
       
  1057      inflateBack() does a raw inflate with a single call using a call-back
       
  1058    interface for input and output.  This is potentially more efficient than
       
  1059    inflate() for file i/o applications, in that it avoids copying between the
       
  1060    output and the sliding window by simply making the window itself the output
       
  1061    buffer.  inflate() can be faster on modern CPUs when used with large
       
  1062    buffers.  inflateBack() trusts the application to not change the output
       
  1063    buffer passed by the output function, at least until inflateBack() returns.
       
  1064 
       
  1065      inflateBackInit() must be called first to allocate the internal state
       
  1066    and to initialize the state with the user-provided window buffer.
       
  1067    inflateBack() may then be used multiple times to inflate a complete, raw
       
  1068    deflate stream with each call.  inflateBackEnd() is then called to free the
       
  1069    allocated state.
       
  1070 
       
  1071      A raw deflate stream is one with no zlib or gzip header or trailer.
       
  1072    This routine would normally be used in a utility that reads zip or gzip
       
  1073    files and writes out uncompressed files.  The utility would decode the
       
  1074    header and process the trailer on its own, hence this routine expects only
       
  1075    the raw deflate stream to decompress.  This is different from the normal
       
  1076    behavior of inflate(), which expects either a zlib or gzip header and
       
  1077    trailer around the deflate stream.
       
  1078 
       
  1079      inflateBack() uses two subroutines supplied by the caller that are then
       
  1080    called by inflateBack() for input and output.  inflateBack() calls those
       
  1081    routines until it reads a complete deflate stream and writes out all of the
       
  1082    uncompressed data, or until it encounters an error.  The function's
       
  1083    parameters and return types are defined above in the in_func and out_func
       
  1084    typedefs.  inflateBack() will call in(in_desc, &buf) which should return the
       
  1085    number of bytes of provided input, and a pointer to that input in buf.  If
       
  1086    there is no input available, in() must return zero--buf is ignored in that
       
  1087    case--and inflateBack() will return a buffer error.  inflateBack() will call
       
  1088    out(out_desc, buf, len) to write the uncompressed data buf[0..len-1].  out()
       
  1089    should return zero on success, or non-zero on failure.  If out() returns
       
  1090    non-zero, inflateBack() will return with an error.  Neither in() nor out()
       
  1091    are permitted to change the contents of the window provided to
       
  1092    inflateBackInit(), which is also the buffer that out() uses to write from.
       
  1093    The length written by out() will be at most the window size.  Any non-zero
       
  1094    amount of input may be provided by in().
       
  1095 
       
  1096      For convenience, inflateBack() can be provided input on the first call by
       
  1097    setting strm->next_in and strm->avail_in.  If that input is exhausted, then
       
  1098    in() will be called.  Therefore strm->next_in must be initialized before
       
  1099    calling inflateBack().  If strm->next_in is Z_NULL, then in() will be called
       
  1100    immediately for input.  If strm->next_in is not Z_NULL, then strm->avail_in
       
  1101    must also be initialized, and then if strm->avail_in is not zero, input will
       
  1102    initially be taken from strm->next_in[0 ..  strm->avail_in - 1].
       
  1103 
       
  1104      The in_desc and out_desc parameters of inflateBack() is passed as the
       
  1105    first parameter of in() and out() respectively when they are called.  These
       
  1106    descriptors can be optionally used to pass any information that the caller-
       
  1107    supplied in() and out() functions need to do their job.
       
  1108 
       
  1109      On return, inflateBack() will set strm->next_in and strm->avail_in to
       
  1110    pass back any unused input that was provided by the last in() call.  The
       
  1111    return values of inflateBack() can be Z_STREAM_END on success, Z_BUF_ERROR
       
  1112    if in() or out() returned an error, Z_DATA_ERROR if there was a format error
       
  1113    in the deflate stream (in which case strm->msg is set to indicate the nature
       
  1114    of the error), or Z_STREAM_ERROR if the stream was not properly initialized.
       
  1115    In the case of Z_BUF_ERROR, an input or output error can be distinguished
       
  1116    using strm->next_in which will be Z_NULL only if in() returned an error.  If
       
  1117    strm->next_in is not Z_NULL, then the Z_BUF_ERROR was due to out() returning
       
  1118    non-zero.  (in() will always be called before out(), so strm->next_in is
       
  1119    assured to be defined if out() returns non-zero.) Note that inflateBack()
       
  1120    cannot return Z_OK.
       
  1121 */
       
  1122 
       
  1123 ZEXTERN int ZEXPORT inflateBackEnd OF((z_streamp strm));
       
  1124 /*
       
  1125      All memory allocated by inflateBackInit() is freed.
       
  1126 
       
  1127      inflateBackEnd() returns Z_OK on success, or Z_STREAM_ERROR if the stream
       
  1128    state was inconsistent.
       
  1129 */
       
  1130 
       
  1131 ZEXTERN uLong ZEXPORT zlibCompileFlags OF((void));
       
  1132 /* Return flags indicating compile-time options.
       
  1133 
       
  1134     Type sizes, two bits each, 00 = 16 bits, 01 = 32, 10 = 64, 11 = other:
       
  1135      1.0: size of uInt
       
  1136      3.2: size of uLong
       
  1137      5.4: size of voidpf (pointer)
       
  1138      7.6: size of z_off_t
       
  1139 
       
  1140     Compiler, assembler, and debug options:
       
  1141      8: DEBUG
       
  1142      9: ASMV or ASMINF -- use ASM code
       
  1143      10: ZLIB_WINAPI -- exported functions use the WINAPI calling convention
       
  1144      11: 0 (reserved)
       
  1145 
       
  1146     One-time table building (smaller code, but not thread-safe if true):
       
  1147      12: BUILDFIXED -- build static block decoding tables when needed
       
  1148      13: DYNAMIC_CRC_TABLE -- build CRC calculation tables when needed
       
  1149      14,15: 0 (reserved)
       
  1150 
       
  1151     Library content (indicates missing functionality):
       
  1152      16: NO_GZCOMPRESS -- gz* functions cannot compress (to avoid linking
       
  1153                           deflate code when not needed)
       
  1154      17: NO_GZIP -- deflate can't write gzip streams, and inflate can't detect
       
  1155                     and decode gzip streams (to avoid linking crc code)
       
  1156      18-19: 0 (reserved)
       
  1157 
       
  1158     Operation variations (changes in library functionality):
       
  1159      20: PKZIP_BUG_WORKAROUND -- slightly more permissive inflate
       
  1160      21: FASTEST -- deflate algorithm with only one, lowest compression level
       
  1161      22,23: 0 (reserved)
       
  1162 
       
  1163     The sprintf variant used by gzprintf (zero is best):
       
  1164      24: 0 = vs*, 1 = s* -- 1 means limited to 20 arguments after the format
       
  1165      25: 0 = *nprintf, 1 = *printf -- 1 means gzprintf() not secure!
       
  1166      26: 0 = returns value, 1 = void -- 1 means inferred string length returned
       
  1167 
       
  1168     Remainder:
       
  1169      27-31: 0 (reserved)
       
  1170  */
       
  1171 
       
  1172 #ifndef Z_SOLO
       
  1173 
       
  1174                         /* utility functions */
       
  1175 
       
  1176 /*
       
  1177      The following utility functions are implemented on top of the basic
       
  1178    stream-oriented functions.  To simplify the interface, some default options
       
  1179    are assumed (compression level and memory usage, standard memory allocation
       
  1180    functions).  The source code of these utility functions can be modified if
       
  1181    you need special options.
       
  1182 */
       
  1183 
       
  1184 ZEXTERN int ZEXPORT compress OF((Bytef *dest,   uLongf *destLen,
       
  1185                                  const Bytef *source, uLong sourceLen));
       
  1186 /*
       
  1187      Compresses the source buffer into the destination buffer.  sourceLen is
       
  1188    the byte length of the source buffer.  Upon entry, destLen is the total size
       
  1189    of the destination buffer, which must be at least the value returned by
       
  1190    compressBound(sourceLen).  Upon exit, destLen is the actual size of the
       
  1191    compressed buffer.
       
  1192 
       
  1193      compress returns Z_OK if success, Z_MEM_ERROR if there was not
       
  1194    enough memory, Z_BUF_ERROR if there was not enough room in the output
       
  1195    buffer.
       
  1196 */
       
  1197 
       
  1198 ZEXTERN int ZEXPORT compress2 OF((Bytef *dest,   uLongf *destLen,
       
  1199                                   const Bytef *source, uLong sourceLen,
       
  1200                                   int level));
       
  1201 /*
       
  1202      Compresses the source buffer into the destination buffer.  The level
       
  1203    parameter has the same meaning as in deflateInit.  sourceLen is the byte
       
  1204    length of the source buffer.  Upon entry, destLen is the total size of the
       
  1205    destination buffer, which must be at least the value returned by
       
  1206    compressBound(sourceLen).  Upon exit, destLen is the actual size of the
       
  1207    compressed buffer.
       
  1208 
       
  1209      compress2 returns Z_OK if success, Z_MEM_ERROR if there was not enough
       
  1210    memory, Z_BUF_ERROR if there was not enough room in the output buffer,
       
  1211    Z_STREAM_ERROR if the level parameter is invalid.
       
  1212 */
       
  1213 
       
  1214 ZEXTERN uLong ZEXPORT compressBound OF((uLong sourceLen));
       
  1215 /*
       
  1216      compressBound() returns an upper bound on the compressed size after
       
  1217    compress() or compress2() on sourceLen bytes.  It would be used before a
       
  1218    compress() or compress2() call to allocate the destination buffer.
       
  1219 */
       
  1220 
       
  1221 ZEXTERN int ZEXPORT uncompress OF((Bytef *dest,   uLongf *destLen,
       
  1222                                    const Bytef *source, uLong sourceLen));
       
  1223 /*
       
  1224      Decompresses the source buffer into the destination buffer.  sourceLen is
       
  1225    the byte length of the source buffer.  Upon entry, destLen is the total size
       
  1226    of the destination buffer, which must be large enough to hold the entire
       
  1227    uncompressed data.  (The size of the uncompressed data must have been saved
       
  1228    previously by the compressor and transmitted to the decompressor by some
       
  1229    mechanism outside the scope of this compression library.) Upon exit, destLen
       
  1230    is the actual size of the uncompressed buffer.
       
  1231 
       
  1232      uncompress returns Z_OK if success, Z_MEM_ERROR if there was not
       
  1233    enough memory, Z_BUF_ERROR if there was not enough room in the output
       
  1234    buffer, or Z_DATA_ERROR if the input data was corrupted or incomplete.  In
       
  1235    the case where there is not enough room, uncompress() will fill the output
       
  1236    buffer with the uncompressed data up to that point.
       
  1237 */
       
  1238 
       
  1239                         /* gzip file access functions */
       
  1240 
       
  1241 /*
       
  1242      This library supports reading and writing files in gzip (.gz) format with
       
  1243    an interface similar to that of stdio, using the functions that start with
       
  1244    "gz".  The gzip format is different from the zlib format.  gzip is a gzip
       
  1245    wrapper, documented in RFC 1952, wrapped around a deflate stream.
       
  1246 */
       
  1247 
       
  1248 typedef struct gzFile_s *gzFile;    /* semi-opaque gzip file descriptor */
       
  1249 
       
  1250 /*
       
  1251 ZEXTERN gzFile ZEXPORT gzopen OF((const char *path, const char *mode));
       
  1252 
       
  1253      Opens a gzip (.gz) file for reading or writing.  The mode parameter is as
       
  1254    in fopen ("rb" or "wb") but can also include a compression level ("wb9") or
       
  1255    a strategy: 'f' for filtered data as in "wb6f", 'h' for Huffman-only
       
  1256    compression as in "wb1h", 'R' for run-length encoding as in "wb1R", or 'F'
       
  1257    for fixed code compression as in "wb9F".  (See the description of
       
  1258    deflateInit2 for more information about the strategy parameter.)  'T' will
       
  1259    request transparent writing or appending with no compression and not using
       
  1260    the gzip format.
       
  1261 
       
  1262      "a" can be used instead of "w" to request that the gzip stream that will
       
  1263    be written be appended to the file.  "+" will result in an error, since
       
  1264    reading and writing to the same gzip file is not supported.  The addition of
       
  1265    "x" when writing will create the file exclusively, which fails if the file
       
  1266    already exists.  On systems that support it, the addition of "e" when
       
  1267    reading or writing will set the flag to close the file on an execve() call.
       
  1268 
       
  1269      These functions, as well as gzip, will read and decode a sequence of gzip
       
  1270    streams in a file.  The append function of gzopen() can be used to create
       
  1271    such a file.  (Also see gzflush() for another way to do this.)  When
       
  1272    appending, gzopen does not test whether the file begins with a gzip stream,
       
  1273    nor does it look for the end of the gzip streams to begin appending.  gzopen
       
  1274    will simply append a gzip stream to the existing file.
       
  1275 
       
  1276      gzopen can be used to read a file which is not in gzip format; in this
       
  1277    case gzread will directly read from the file without decompression.  When
       
  1278    reading, this will be detected automatically by looking for the magic two-
       
  1279    byte gzip header.
       
  1280 
       
  1281      gzopen returns NULL if the file could not be opened, if there was
       
  1282    insufficient memory to allocate the gzFile state, or if an invalid mode was
       
  1283    specified (an 'r', 'w', or 'a' was not provided, or '+' was provided).
       
  1284    errno can be checked to determine if the reason gzopen failed was that the
       
  1285    file could not be opened.
       
  1286 */
       
  1287 
       
  1288 ZEXTERN gzFile ZEXPORT gzdopen OF((int fd, const char *mode));
       
  1289 /*
       
  1290      gzdopen associates a gzFile with the file descriptor fd.  File descriptors
       
  1291    are obtained from calls like open, dup, creat, pipe or fileno (if the file
       
  1292    has been previously opened with fopen).  The mode parameter is as in gzopen.
       
  1293 
       
  1294      The next call of gzclose on the returned gzFile will also close the file
       
  1295    descriptor fd, just like fclose(fdopen(fd, mode)) closes the file descriptor
       
  1296    fd.  If you want to keep fd open, use fd = dup(fd_keep); gz = gzdopen(fd,
       
  1297    mode);.  The duplicated descriptor should be saved to avoid a leak, since
       
  1298    gzdopen does not close fd if it fails.  If you are using fileno() to get the
       
  1299    file descriptor from a FILE *, then you will have to use dup() to avoid
       
  1300    double-close()ing the file descriptor.  Both gzclose() and fclose() will
       
  1301    close the associated file descriptor, so they need to have different file
       
  1302    descriptors.
       
  1303 
       
  1304      gzdopen returns NULL if there was insufficient memory to allocate the
       
  1305    gzFile state, if an invalid mode was specified (an 'r', 'w', or 'a' was not
       
  1306    provided, or '+' was provided), or if fd is -1.  The file descriptor is not
       
  1307    used until the next gz* read, write, seek, or close operation, so gzdopen
       
  1308    will not detect if fd is invalid (unless fd is -1).
       
  1309 */
       
  1310 
       
  1311 ZEXTERN int ZEXPORT gzbuffer OF((gzFile file, unsigned size));
       
  1312 /*
       
  1313      Set the internal buffer size used by this library's functions.  The
       
  1314    default buffer size is 8192 bytes.  This function must be called after
       
  1315    gzopen() or gzdopen(), and before any other calls that read or write the
       
  1316    file.  The buffer memory allocation is always deferred to the first read or
       
  1317    write.  Two buffers are allocated, either both of the specified size when
       
  1318    writing, or one of the specified size and the other twice that size when
       
  1319    reading.  A larger buffer size of, for example, 64K or 128K bytes will
       
  1320    noticeably increase the speed of decompression (reading).
       
  1321 
       
  1322      The new buffer size also affects the maximum length for gzprintf().
       
  1323 
       
  1324      gzbuffer() returns 0 on success, or -1 on failure, such as being called
       
  1325    too late.
       
  1326 */
       
  1327 
       
  1328 ZEXTERN int ZEXPORT gzsetparams OF((gzFile file, int level, int strategy));
       
  1329 /*
       
  1330      Dynamically update the compression level or strategy.  See the description
       
  1331    of deflateInit2 for the meaning of these parameters.
       
  1332 
       
  1333      gzsetparams returns Z_OK if success, or Z_STREAM_ERROR if the file was not
       
  1334    opened for writing.
       
  1335 */
       
  1336 
       
  1337 ZEXTERN int ZEXPORT gzread OF((gzFile file, voidp buf, unsigned len));
       
  1338 /*
       
  1339      Reads the given number of uncompressed bytes from the compressed file.  If
       
  1340    the input file is not in gzip format, gzread copies the given number of
       
  1341    bytes into the buffer directly from the file.
       
  1342 
       
  1343      After reaching the end of a gzip stream in the input, gzread will continue
       
  1344    to read, looking for another gzip stream.  Any number of gzip streams may be
       
  1345    concatenated in the input file, and will all be decompressed by gzread().
       
  1346    If something other than a gzip stream is encountered after a gzip stream,
       
  1347    that remaining trailing garbage is ignored (and no error is returned).
       
  1348 
       
  1349      gzread can be used to read a gzip file that is being concurrently written.
       
  1350    Upon reaching the end of the input, gzread will return with the available
       
  1351    data.  If the error code returned by gzerror is Z_OK or Z_BUF_ERROR, then
       
  1352    gzclearerr can be used to clear the end of file indicator in order to permit
       
  1353    gzread to be tried again.  Z_OK indicates that a gzip stream was completed
       
  1354    on the last gzread.  Z_BUF_ERROR indicates that the input file ended in the
       
  1355    middle of a gzip stream.  Note that gzread does not return -1 in the event
       
  1356    of an incomplete gzip stream.  This error is deferred until gzclose(), which
       
  1357    will return Z_BUF_ERROR if the last gzread ended in the middle of a gzip
       
  1358    stream.  Alternatively, gzerror can be used before gzclose to detect this
       
  1359    case.
       
  1360 
       
  1361      gzread returns the number of uncompressed bytes actually read, less than
       
  1362    len for end of file, or -1 for error.
       
  1363 */
       
  1364 
       
  1365 ZEXTERN int ZEXPORT gzwrite OF((gzFile file,
       
  1366                                 voidpc buf, unsigned len));
       
  1367 /*
       
  1368      Writes the given number of uncompressed bytes into the compressed file.
       
  1369    gzwrite returns the number of uncompressed bytes written or 0 in case of
       
  1370    error.
       
  1371 */
       
  1372 
       
  1373 ZEXTERN int ZEXPORTVA gzprintf Z_ARG((gzFile file, const char *format, ...));
       
  1374 /*
       
  1375      Converts, formats, and writes the arguments to the compressed file under
       
  1376    control of the format string, as in fprintf.  gzprintf returns the number of
       
  1377    uncompressed bytes actually written, or 0 in case of error.  The number of
       
  1378    uncompressed bytes written is limited to 8191, or one less than the buffer
       
  1379    size given to gzbuffer().  The caller should assure that this limit is not
       
  1380    exceeded.  If it is exceeded, then gzprintf() will return an error (0) with
       
  1381    nothing written.  In this case, there may also be a buffer overflow with
       
  1382    unpredictable consequences, which is possible only if zlib was compiled with
       
  1383    the insecure functions sprintf() or vsprintf() because the secure snprintf()
       
  1384    or vsnprintf() functions were not available.  This can be determined using
       
  1385    zlibCompileFlags().
       
  1386 */
       
  1387 
       
  1388 ZEXTERN int ZEXPORT gzputs OF((gzFile file, const char *s));
       
  1389 /*
       
  1390      Writes the given null-terminated string to the compressed file, excluding
       
  1391    the terminating null character.
       
  1392 
       
  1393      gzputs returns the number of characters written, or -1 in case of error.
       
  1394 */
       
  1395 
       
  1396 ZEXTERN char * ZEXPORT gzgets OF((gzFile file, char *buf, int len));
       
  1397 /*
       
  1398      Reads bytes from the compressed file until len-1 characters are read, or a
       
  1399    newline character is read and transferred to buf, or an end-of-file
       
  1400    condition is encountered.  If any characters are read or if len == 1, the
       
  1401    string is terminated with a null character.  If no characters are read due
       
  1402    to an end-of-file or len < 1, then the buffer is left untouched.
       
  1403 
       
  1404      gzgets returns buf which is a null-terminated string, or it returns NULL
       
  1405    for end-of-file or in case of error.  If there was an error, the contents at
       
  1406    buf are indeterminate.
       
  1407 */
       
  1408 
       
  1409 ZEXTERN int ZEXPORT gzputc OF((gzFile file, int c));
       
  1410 /*
       
  1411      Writes c, converted to an unsigned char, into the compressed file.  gzputc
       
  1412    returns the value that was written, or -1 in case of error.
       
  1413 */
       
  1414 
       
  1415 ZEXTERN int ZEXPORT gzgetc OF((gzFile file));
       
  1416 /*
       
  1417      Reads one byte from the compressed file.  gzgetc returns this byte or -1
       
  1418    in case of end of file or error.  This is implemented as a macro for speed.
       
  1419    As such, it does not do all of the checking the other functions do.  I.e.
       
  1420    it does not check to see if file is NULL, nor whether the structure file
       
  1421    points to has been clobbered or not.
       
  1422 */
       
  1423 
       
  1424 ZEXTERN int ZEXPORT gzungetc OF((int c, gzFile file));
       
  1425 /*
       
  1426      Push one character back onto the stream to be read as the first character
       
  1427    on the next read.  At least one character of push-back is allowed.
       
  1428    gzungetc() returns the character pushed, or -1 on failure.  gzungetc() will
       
  1429    fail if c is -1, and may fail if a character has been pushed but not read
       
  1430    yet.  If gzungetc is used immediately after gzopen or gzdopen, at least the
       
  1431    output buffer size of pushed characters is allowed.  (See gzbuffer above.)
       
  1432    The pushed character will be discarded if the stream is repositioned with
       
  1433    gzseek() or gzrewind().
       
  1434 */
       
  1435 
       
  1436 ZEXTERN int ZEXPORT gzflush OF((gzFile file, int flush));
       
  1437 /*
       
  1438      Flushes all pending output into the compressed file.  The parameter flush
       
  1439    is as in the deflate() function.  The return value is the zlib error number
       
  1440    (see function gzerror below).  gzflush is only permitted when writing.
       
  1441 
       
  1442      If the flush parameter is Z_FINISH, the remaining data is written and the
       
  1443    gzip stream is completed in the output.  If gzwrite() is called again, a new
       
  1444    gzip stream will be started in the output.  gzread() is able to read such
       
  1445    concatented gzip streams.
       
  1446 
       
  1447      gzflush should be called only when strictly necessary because it will
       
  1448    degrade compression if called too often.
       
  1449 */
       
  1450 
       
  1451 /*
       
  1452 ZEXTERN z_off_t ZEXPORT gzseek OF((gzFile file,
       
  1453                                    z_off_t offset, int whence));
       
  1454 
       
  1455      Sets the starting position for the next gzread or gzwrite on the given
       
  1456    compressed file.  The offset represents a number of bytes in the
       
  1457    uncompressed data stream.  The whence parameter is defined as in lseek(2);
       
  1458    the value SEEK_END is not supported.
       
  1459 
       
  1460      If the file is opened for reading, this function is emulated but can be
       
  1461    extremely slow.  If the file is opened for writing, only forward seeks are
       
  1462    supported; gzseek then compresses a sequence of zeroes up to the new
       
  1463    starting position.
       
  1464 
       
  1465      gzseek returns the resulting offset location as measured in bytes from
       
  1466    the beginning of the uncompressed stream, or -1 in case of error, in
       
  1467    particular if the file is opened for writing and the new starting position
       
  1468    would be before the current position.
       
  1469 */
       
  1470 
       
  1471 ZEXTERN int ZEXPORT    gzrewind OF((gzFile file));
       
  1472 /*
       
  1473      Rewinds the given file. This function is supported only for reading.
       
  1474 
       
  1475      gzrewind(file) is equivalent to (int)gzseek(file, 0L, SEEK_SET)
       
  1476 */
       
  1477 
       
  1478 /*
       
  1479 ZEXTERN z_off_t ZEXPORT    gztell OF((gzFile file));
       
  1480 
       
  1481      Returns the starting position for the next gzread or gzwrite on the given
       
  1482    compressed file.  This position represents a number of bytes in the
       
  1483    uncompressed data stream, and is zero when starting, even if appending or
       
  1484    reading a gzip stream from the middle of a file using gzdopen().
       
  1485 
       
  1486      gztell(file) is equivalent to gzseek(file, 0L, SEEK_CUR)
       
  1487 */
       
  1488 
       
  1489 /*
       
  1490 ZEXTERN z_off_t ZEXPORT gzoffset OF((gzFile file));
       
  1491 
       
  1492      Returns the current offset in the file being read or written.  This offset
       
  1493    includes the count of bytes that precede the gzip stream, for example when
       
  1494    appending or when using gzdopen() for reading.  When reading, the offset
       
  1495    does not include as yet unused buffered input.  This information can be used
       
  1496    for a progress indicator.  On error, gzoffset() returns -1.
       
  1497 */
       
  1498 
       
  1499 ZEXTERN int ZEXPORT gzeof OF((gzFile file));
       
  1500 /*
       
  1501      Returns true (1) if the end-of-file indicator has been set while reading,
       
  1502    false (0) otherwise.  Note that the end-of-file indicator is set only if the
       
  1503    read tried to go past the end of the input, but came up short.  Therefore,
       
  1504    just like feof(), gzeof() may return false even if there is no more data to
       
  1505    read, in the event that the last read request was for the exact number of
       
  1506    bytes remaining in the input file.  This will happen if the input file size
       
  1507    is an exact multiple of the buffer size.
       
  1508 
       
  1509      If gzeof() returns true, then the read functions will return no more data,
       
  1510    unless the end-of-file indicator is reset by gzclearerr() and the input file
       
  1511    has grown since the previous end of file was detected.
       
  1512 */
       
  1513 
       
  1514 ZEXTERN int ZEXPORT gzdirect OF((gzFile file));
       
  1515 /*
       
  1516      Returns true (1) if file is being copied directly while reading, or false
       
  1517    (0) if file is a gzip stream being decompressed.
       
  1518 
       
  1519      If the input file is empty, gzdirect() will return true, since the input
       
  1520    does not contain a gzip stream.
       
  1521 
       
  1522      If gzdirect() is used immediately after gzopen() or gzdopen() it will
       
  1523    cause buffers to be allocated to allow reading the file to determine if it
       
  1524    is a gzip file.  Therefore if gzbuffer() is used, it should be called before
       
  1525    gzdirect().
       
  1526 
       
  1527      When writing, gzdirect() returns true (1) if transparent writing was
       
  1528    requested ("wT" for the gzopen() mode), or false (0) otherwise.  (Note:
       
  1529    gzdirect() is not needed when writing.  Transparent writing must be
       
  1530    explicitly requested, so the application already knows the answer.  When
       
  1531    linking statically, using gzdirect() will include all of the zlib code for
       
  1532    gzip file reading and decompression, which may not be desired.)
       
  1533 */
       
  1534 
       
  1535 ZEXTERN int ZEXPORT    gzclose OF((gzFile file));
       
  1536 /*
       
  1537      Flushes all pending output if necessary, closes the compressed file and
       
  1538    deallocates the (de)compression state.  Note that once file is closed, you
       
  1539    cannot call gzerror with file, since its structures have been deallocated.
       
  1540    gzclose must not be called more than once on the same file, just as free
       
  1541    must not be called more than once on the same allocation.
       
  1542 
       
  1543      gzclose will return Z_STREAM_ERROR if file is not valid, Z_ERRNO on a
       
  1544    file operation error, Z_MEM_ERROR if out of memory, Z_BUF_ERROR if the
       
  1545    last read ended in the middle of a gzip stream, or Z_OK on success.
       
  1546 */
       
  1547 
       
  1548 ZEXTERN int ZEXPORT gzclose_r OF((gzFile file));
       
  1549 ZEXTERN int ZEXPORT gzclose_w OF((gzFile file));
       
  1550 /*
       
  1551      Same as gzclose(), but gzclose_r() is only for use when reading, and
       
  1552    gzclose_w() is only for use when writing or appending.  The advantage to
       
  1553    using these instead of gzclose() is that they avoid linking in zlib
       
  1554    compression or decompression code that is not used when only reading or only
       
  1555    writing respectively.  If gzclose() is used, then both compression and
       
  1556    decompression code will be included the application when linking to a static
       
  1557    zlib library.
       
  1558 */
       
  1559 
       
  1560 ZEXTERN const char * ZEXPORT gzerror OF((gzFile file, int *errnum));
       
  1561 /*
       
  1562      Returns the error message for the last error which occurred on the given
       
  1563    compressed file.  errnum is set to zlib error number.  If an error occurred
       
  1564    in the file system and not in the compression library, errnum is set to
       
  1565    Z_ERRNO and the application may consult errno to get the exact error code.
       
  1566 
       
  1567      The application must not modify the returned string.  Future calls to
       
  1568    this function may invalidate the previously returned string.  If file is
       
  1569    closed, then the string previously returned by gzerror will no longer be
       
  1570    available.
       
  1571 
       
  1572      gzerror() should be used to distinguish errors from end-of-file for those
       
  1573    functions above that do not distinguish those cases in their return values.
       
  1574 */
       
  1575 
       
  1576 ZEXTERN void ZEXPORT gzclearerr OF((gzFile file));
       
  1577 /*
       
  1578      Clears the error and end-of-file flags for file.  This is analogous to the
       
  1579    clearerr() function in stdio.  This is useful for continuing to read a gzip
       
  1580    file that is being written concurrently.
       
  1581 */
       
  1582 
       
  1583 #endif /* !Z_SOLO */
       
  1584 
       
  1585                         /* checksum functions */
       
  1586 
       
  1587 /*
       
  1588      These functions are not related to compression but are exported
       
  1589    anyway because they might be useful in applications using the compression
       
  1590    library.
       
  1591 */
       
  1592 
       
  1593 ZEXTERN uLong ZEXPORT adler32 OF((uLong adler, const Bytef *buf, uInt len));
       
  1594 /*
       
  1595      Update a running Adler-32 checksum with the bytes buf[0..len-1] and
       
  1596    return the updated checksum.  If buf is Z_NULL, this function returns the
       
  1597    required initial value for the checksum.
       
  1598 
       
  1599      An Adler-32 checksum is almost as reliable as a CRC32 but can be computed
       
  1600    much faster.
       
  1601 
       
  1602    Usage example:
       
  1603 
       
  1604      uLong adler = adler32(0L, Z_NULL, 0);
       
  1605 
       
  1606      while (read_buffer(buffer, length) != EOF) {
       
  1607        adler = adler32(adler, buffer, length);
       
  1608      }
       
  1609      if (adler != original_adler) error();
       
  1610 */
       
  1611 
       
  1612 /*
       
  1613 ZEXTERN uLong ZEXPORT adler32_combine OF((uLong adler1, uLong adler2,
       
  1614                                           z_off_t len2));
       
  1615 
       
  1616      Combine two Adler-32 checksums into one.  For two sequences of bytes, seq1
       
  1617    and seq2 with lengths len1 and len2, Adler-32 checksums were calculated for
       
  1618    each, adler1 and adler2.  adler32_combine() returns the Adler-32 checksum of
       
  1619    seq1 and seq2 concatenated, requiring only adler1, adler2, and len2.  Note
       
  1620    that the z_off_t type (like off_t) is a signed integer.  If len2 is
       
  1621    negative, the result has no meaning or utility.
       
  1622 */
       
  1623 
       
  1624 ZEXTERN uLong ZEXPORT crc32   OF((uLong crc, const Bytef *buf, uInt len));
       
  1625 /*
       
  1626      Update a running CRC-32 with the bytes buf[0..len-1] and return the
       
  1627    updated CRC-32.  If buf is Z_NULL, this function returns the required
       
  1628    initial value for the crc.  Pre- and post-conditioning (one's complement) is
       
  1629    performed within this function so it shouldn't be done by the application.
       
  1630 
       
  1631    Usage example:
       
  1632 
       
  1633      uLong crc = crc32(0L, Z_NULL, 0);
       
  1634 
       
  1635      while (read_buffer(buffer, length) != EOF) {
       
  1636        crc = crc32(crc, buffer, length);
       
  1637      }
       
  1638      if (crc != original_crc) error();
       
  1639 */
       
  1640 
       
  1641 /*
       
  1642 ZEXTERN uLong ZEXPORT crc32_combine OF((uLong crc1, uLong crc2, z_off_t len2));
       
  1643 
       
  1644      Combine two CRC-32 check values into one.  For two sequences of bytes,
       
  1645    seq1 and seq2 with lengths len1 and len2, CRC-32 check values were
       
  1646    calculated for each, crc1 and crc2.  crc32_combine() returns the CRC-32
       
  1647    check value of seq1 and seq2 concatenated, requiring only crc1, crc2, and
       
  1648    len2.
       
  1649 */
       
  1650 
       
  1651 
       
  1652                         /* various hacks, don't look :) */
       
  1653 
       
  1654 /* deflateInit and inflateInit are macros to allow checking the zlib version
       
  1655  * and the compiler's view of z_stream:
       
  1656  */
       
  1657 ZEXTERN int ZEXPORT deflateInit_ OF((z_streamp strm, int level,
       
  1658                                      const char *version, int stream_size));
       
  1659 ZEXTERN int ZEXPORT inflateInit_ OF((z_streamp strm,
       
  1660                                      const char *version, int stream_size));
       
  1661 ZEXTERN int ZEXPORT deflateInit2_ OF((z_streamp strm, int  level, int  method,
       
  1662                                       int windowBits, int memLevel,
       
  1663                                       int strategy, const char *version,
       
  1664                                       int stream_size));
       
  1665 ZEXTERN int ZEXPORT inflateInit2_ OF((z_streamp strm, int  windowBits,
       
  1666                                       const char *version, int stream_size));
       
  1667 ZEXTERN int ZEXPORT inflateBackInit_ OF((z_streamp strm, int windowBits,
       
  1668                                          unsigned char FAR *window,
       
  1669                                          const char *version,
       
  1670                                          int stream_size));
       
  1671 #define deflateInit(strm, level) \
       
  1672         deflateInit_((strm), (level), ZLIB_VERSION, (int)sizeof(z_stream))
       
  1673 #define inflateInit(strm) \
       
  1674         inflateInit_((strm), ZLIB_VERSION, (int)sizeof(z_stream))
       
  1675 #define deflateInit2(strm, level, method, windowBits, memLevel, strategy) \
       
  1676         deflateInit2_((strm),(level),(method),(windowBits),(memLevel),\
       
  1677                       (strategy), ZLIB_VERSION, (int)sizeof(z_stream))
       
  1678 #define inflateInit2(strm, windowBits) \
       
  1679         inflateInit2_((strm), (windowBits), ZLIB_VERSION, \
       
  1680                       (int)sizeof(z_stream))
       
  1681 #define inflateBackInit(strm, windowBits, window) \
       
  1682         inflateBackInit_((strm), (windowBits), (window), \
       
  1683                       ZLIB_VERSION, (int)sizeof(z_stream))
       
  1684 
       
  1685 #ifndef Z_SOLO
       
  1686 
       
  1687 /* gzgetc() macro and its supporting function and exposed data structure.  Note
       
  1688  * that the real internal state is much larger than the exposed structure.
       
  1689  * This abbreviated structure exposes just enough for the gzgetc() macro.  The
       
  1690  * user should not mess with these exposed elements, since their names or
       
  1691  * behavior could change in the future, perhaps even capriciously.  They can
       
  1692  * only be used by the gzgetc() macro.  You have been warned.
       
  1693  */
       
  1694 struct gzFile_s {
       
  1695     unsigned have;
       
  1696     unsigned char *next;
       
  1697     z_off64_t pos;
       
  1698 };
       
  1699 ZEXTERN int ZEXPORT gzgetc_ OF((gzFile file));  /* backward compatibility */
       
  1700 #ifdef Z_PREFIX_SET
       
  1701 #  undef z_gzgetc
       
  1702 #  define z_gzgetc(g) \
       
  1703           ((g)->have ? ((g)->have--, (g)->pos++, *((g)->next)++) : gzgetc(g))
       
  1704 #else
       
  1705 #  define gzgetc(g) \
       
  1706           ((g)->have ? ((g)->have--, (g)->pos++, *((g)->next)++) : gzgetc(g))
       
  1707 #endif
       
  1708 
       
  1709 /* provide 64-bit offset functions if _LARGEFILE64_SOURCE defined, and/or
       
  1710  * change the regular functions to 64 bits if _FILE_OFFSET_BITS is 64 (if
       
  1711  * both are true, the application gets the *64 functions, and the regular
       
  1712  * functions are changed to 64 bits) -- in case these are set on systems
       
  1713  * without large file support, _LFS64_LARGEFILE must also be true
       
  1714  */
       
  1715 #ifdef Z_LARGE64
       
  1716    ZEXTERN gzFile ZEXPORT gzopen64 OF((const char *, const char *));
       
  1717    ZEXTERN z_off64_t ZEXPORT gzseek64 OF((gzFile, z_off64_t, int));
       
  1718    ZEXTERN z_off64_t ZEXPORT gztell64 OF((gzFile));
       
  1719    ZEXTERN z_off64_t ZEXPORT gzoffset64 OF((gzFile));
       
  1720    ZEXTERN uLong ZEXPORT adler32_combine64 OF((uLong, uLong, z_off64_t));
       
  1721    ZEXTERN uLong ZEXPORT crc32_combine64 OF((uLong, uLong, z_off64_t));
       
  1722 #endif
       
  1723 
       
  1724 #if !defined(ZLIB_INTERNAL) && defined(Z_WANT64)
       
  1725 #  ifdef Z_PREFIX_SET
       
  1726 #    define z_gzopen z_gzopen64
       
  1727 #    define z_gzseek z_gzseek64
       
  1728 #    define z_gztell z_gztell64
       
  1729 #    define z_gzoffset z_gzoffset64
       
  1730 #    define z_adler32_combine z_adler32_combine64
       
  1731 #    define z_crc32_combine z_crc32_combine64
       
  1732 #  else
       
  1733 #    define gzopen gzopen64
       
  1734 #    define gzseek gzseek64
       
  1735 #    define gztell gztell64
       
  1736 #    define gzoffset gzoffset64
       
  1737 #    define adler32_combine adler32_combine64
       
  1738 #    define crc32_combine crc32_combine64
       
  1739 #  endif
       
  1740 #  ifndef Z_LARGE64
       
  1741      ZEXTERN gzFile ZEXPORT gzopen64 OF((const char *, const char *));
       
  1742      ZEXTERN z_off_t ZEXPORT gzseek64 OF((gzFile, z_off_t, int));
       
  1743      ZEXTERN z_off_t ZEXPORT gztell64 OF((gzFile));
       
  1744      ZEXTERN z_off_t ZEXPORT gzoffset64 OF((gzFile));
       
  1745      ZEXTERN uLong ZEXPORT adler32_combine64 OF((uLong, uLong, z_off_t));
       
  1746      ZEXTERN uLong ZEXPORT crc32_combine64 OF((uLong, uLong, z_off_t));
       
  1747 #  endif
       
  1748 #else
       
  1749    ZEXTERN gzFile ZEXPORT gzopen OF((const char *, const char *));
       
  1750    ZEXTERN z_off_t ZEXPORT gzseek OF((gzFile, z_off_t, int));
       
  1751    ZEXTERN z_off_t ZEXPORT gztell OF((gzFile));
       
  1752    ZEXTERN z_off_t ZEXPORT gzoffset OF((gzFile));
       
  1753    ZEXTERN uLong ZEXPORT adler32_combine OF((uLong, uLong, z_off_t));
       
  1754    ZEXTERN uLong ZEXPORT crc32_combine OF((uLong, uLong, z_off_t));
       
  1755 #endif
       
  1756 
       
  1757 #else /* Z_SOLO */
       
  1758 
       
  1759    ZEXTERN uLong ZEXPORT adler32_combine OF((uLong, uLong, z_off_t));
       
  1760    ZEXTERN uLong ZEXPORT crc32_combine OF((uLong, uLong, z_off_t));
       
  1761 
       
  1762 #endif /* !Z_SOLO */
       
  1763 
       
  1764 /* hack for buggy compilers */
       
  1765 #if !defined(ZUTIL_H) && !defined(NO_DUMMY_DECL)
       
  1766     struct internal_state {int dummy;};
       
  1767 #endif
       
  1768 
       
  1769 /* undocumented functions */
       
  1770 ZEXTERN const char   * ZEXPORT zError           OF((int));
       
  1771 ZEXTERN int            ZEXPORT inflateSyncPoint OF((z_streamp));
       
  1772 ZEXTERN const z_crc_t FAR * ZEXPORT get_crc_table    OF((void));
       
  1773 ZEXTERN int            ZEXPORT inflateUndermine OF((z_streamp, int));
       
  1774 ZEXTERN int            ZEXPORT inflateResetKeep OF((z_streamp));
       
  1775 ZEXTERN int            ZEXPORT deflateResetKeep OF((z_streamp));
       
  1776 #if defined(_WIN32) && !defined(Z_SOLO)
       
  1777 ZEXTERN gzFile         ZEXPORT gzopen_w OF((const wchar_t *path,
       
  1778                                             const char *mode));
       
  1779 #endif
       
  1780 #if defined(STDC) || defined(Z_HAVE_STDARG_H)
       
  1781 #  ifndef Z_SOLO
       
  1782 ZEXTERN int            ZEXPORTVA gzvprintf Z_ARG((gzFile file,
       
  1783                                                   const char *format,
       
  1784                                                   va_list va));
       
  1785 #  endif
       
  1786 #endif
       
  1787 
       
  1788 #ifdef __cplusplus
       
  1789 }
       
  1790 #endif
       
  1791 
       
  1792 #endif /* ZLIB_H */