Update Zlib to version 1.2.8

third_party/zlib/zlib.h

 /* zlib.h -- interface of the 'zlib' general purpose compression library
-  version 1.2.5, April 19th, 2010
+  version 1.2.8, April 28th, 2013
 
-  Copyright (C) 1995-2010 Jean-loup Gailly and Mark Adler
+  Copyright (C) 1995-2013 Jean-loup Gailly and Mark Adler
 
   This software is provided 'as-is', without any express or implied
   warranty.  In no event will the authors be held liable for any damages
   arising from the use of this software.
 
   Permission is granted to anyone to use this software for any purpose,
   including commercial applications, and to alter it and redistribute it
   freely, subject to the following restrictions:
 
   1. The origin of this software must not be misrepresented; you must not
      claim that you wrote the original software. If you use this software
      in a product, an acknowledgment in the product documentation would be
      appreciated but is not required.
   2. Altered source versions must be plainly marked as such, and must not be
      misrepresented as being the original software.
   3. This notice may not be removed or altered from any source distribution.
 
   Jean-loup Gailly        Mark Adler
   jloup@gzip.org          madler@alumni.caltech.edu
 
 
   The data format used by the zlib library is described by RFCs (Request for
-  Comments) 1950 to 1952 in the files http://www.ietf.org/rfc/rfc1950.txt
-  (zlib format), rfc1951.txt (deflate format) and rfc1952.txt (gzip format).
+  Comments) 1950 to 1952 in the files http://tools.ietf.org/html/rfc1950
+  (zlib format), rfc1951 (deflate format) and rfc1952 (gzip format).
 */
 
 #ifndef ZLIB_H
 #define ZLIB_H
 
 #include "zconf.h"
 
 #ifdef __cplusplus
 extern "C" {
 #endif
 
-#define ZLIB_VERSION "1.2.5"
-#define ZLIB_VERNUM 0x1250
+#define ZLIB_VERSION "1.2.8"
+#define ZLIB_VERNUM 0x1280
 #define ZLIB_VER_MAJOR 1
 #define ZLIB_VER_MINOR 2
-#define ZLIB_VER_REVISION 5
+#define ZLIB_VER_REVISION 8
 #define ZLIB_VER_SUBREVISION 0
 
 /*
     The 'zlib' compression library provides in-memory compression and
   decompression functions, including integrity checks of the uncompressed data.
   This version of the library supports only one compression method (deflation)
   but other algorithms will be added later and will have the same stream
   interface.
 
     Compression can be done in a single step if the buffers are large enough,
@@ skipping 21 matching lines @@
   the consistency of the compressed data, so the library should never crash
   even in case of corrupted input.
 */
 
 typedef voidpf (*alloc_func) OF((voidpf opaque, uInt items, uInt size));
 typedef void   (*free_func)  OF((voidpf opaque, voidpf address));
 
 struct internal_state;
 
 typedef struct z_stream_s {
-    Bytef    *next_in;  /* next input byte */
+    z_const Bytef *next_in;     /* next input byte */
     uInt     avail_in;  /* number of bytes available at next_in */
-    uLong    total_in;  /* total nb of input bytes read so far */
+    uLong    total_in;  /* total number of input bytes read so far */
 
     Bytef    *next_out; /* next output byte should be put there */
     uInt     avail_out; /* remaining free space at next_out */
-    uLong    total_out; /* total nb of bytes output so far */
+    uLong    total_out; /* total number of bytes output so far */
 
-    char     *msg;      /* last error message, NULL if no error */
+    z_const char *msg;  /* last error message, NULL if no error */
     struct internal_state FAR *state; /* not visible by applications */
 
     alloc_func zalloc;  /* used to allocate the internal state */
     free_func  zfree;   /* used to free the internal state */
     voidpf     opaque;  /* private data object passed to zalloc and zfree */
 
     int     data_type;  /* best guess about the data type: binary or text */
     uLong   adler;      /* adler32 value of the uncompressed data */
     uLong   reserved;   /* reserved for future use */
     int     clas;
@@ skipping 220 matching lines @@
     If the parameter flush is set to Z_FINISH, pending input is processed,
   pending output is flushed and deflate returns with Z_STREAM_END if there was
   enough output space; if deflate returns with Z_OK, this function must be
   called again with Z_FINISH and more output space (updated avail_out) but no
   more input data, until it returns with Z_STREAM_END or an error.  After
   deflate has returned Z_STREAM_END, the only possible operations on the stream
   are deflateReset or deflateEnd.
 
     Z_FINISH can be used immediately after deflateInit if all the compression
   is to be done in a single step.  In this case, avail_out must be at least the
-  value returned by deflateBound (see below).  If deflate does not return
-  Z_STREAM_END, then it must be called again as described above.
+  value returned by deflateBound (see below).  Then deflate is guaranteed to
+  return Z_STREAM_END.  If not enough output space is provided, deflate will
+  not return Z_STREAM_END, and it must be called again as described above.
 
     deflate() sets strm->adler to the adler32 checksum of all input read
   so far (that is, total_in bytes).
 
     deflate() may update strm->data_type if it can make a good guess about
   the input data type (Z_BINARY or Z_TEXT).  In doubt, the data is considered
   binary.  This field is only for information purposes and does not affect the
   compression algorithm in any manner.
 
     deflate() returns Z_OK if some progress has been made (more input
@@ skipping 102 matching lines @@
   end of each deflate block header is reached, before any actual data in that
   block is decoded.  This allows the caller to determine the length of the
   deflate block header for later use in random access within a deflate block.
   256 is added to the value of strm->data_type when inflate() returns
   immediately after reaching the end of the deflate block header.
 
     inflate() should normally be called until it returns Z_STREAM_END or an
   error.  However if all decompression is to be performed in a single step (a
   single call of inflate), the parameter flush should be set to Z_FINISH.  In
   this case all pending input is processed and all pending output is flushed;
-  avail_out must be large enough to hold all the uncompressed data.  (The size
-  of the uncompressed data may have been saved by the compressor for this
-  purpose.) The next operation on this stream must be inflateEnd to deallocate
-  the decompression state.  The use of Z_FINISH is never required, but can be
-  used to inform inflate that a faster approach may be used for the single
-  inflate() call.
+  avail_out must be large enough to hold all of the uncompressed data for the
+  operation to complete.  (The size of the uncompressed data may have been
+  saved by the compressor for this purpose.) The use of Z_FINISH is not
+  required to perform an inflation in one step.  However it may be used to
+  inform inflate that a faster approach can be used for the single inflate()
+  call.  Z_FINISH also informs inflate to not maintain a sliding window if the
+  stream completes, which reduces inflate's memory footprint.  If the stream
+  does not complete, either because not all of the stream is provided or not
+  enough output space is provided, then a sliding window will be allocated and
+  inflate() can be called again to continue the operation as if Z_NO_FLUSH had
+  been used.
 
      In this implementation, inflate() always flushes as much output as
   possible to the output buffer, and always uses the faster approach on the
-  first call.  So the only effect of the flush parameter in this implementation
-  is on the return value of inflate(), as noted below, or when it returns early
-  because Z_BLOCK or Z_TREES is used.
+  first call.  So the effects of the flush parameter in this implementation are
+  on the return value of inflate() as noted below, when inflate() returns early
+  when Z_BLOCK or Z_TREES is used, and when inflate() avoids the allocation of
+  memory for a sliding window when Z_FINISH is used.
 
      If a preset dictionary is needed after this call (see inflateSetDictionary
-  below), inflate sets strm->adler to the adler32 checksum of the dictionary
+  below), inflate sets strm->adler to the Adler-32 checksum of the dictionary
   chosen by the compressor and returns Z_NEED_DICT; otherwise it sets
-  strm->adler to the adler32 checksum of all output produced so far (that is,
+  strm->adler to the Adler-32 checksum of all output produced so far (that is,
   total_out bytes) and returns Z_OK, Z_STREAM_END or an error code as described
   below.  At the end of the stream, inflate() checks that its computed adler32
   checksum is equal to that saved by the compressor and returns Z_STREAM_END
   only if the checksum is correct.
 
     inflate() can decompress and check either zlib-wrapped or gzip-wrapped
   deflate data.  The header type is detected automatically, if requested when
   initializing with inflateInit2().  Any information contained in the gzip
   header is not retained, so applications that need that information should
   instead use raw inflate, see inflateInit2() below, or inflateBack() and
-  perform their own processing of the gzip header and trailer.
+  perform their own processing of the gzip header and trailer.  When processing
+  gzip-wrapped deflate data, strm->adler32 is set to the CRC-32 of the output
+  producted so far.  The CRC-32 is checked against the gzip trailer.
 
     inflate() returns Z_OK if some progress has been made (more input processed
   or more output produced), Z_STREAM_END if the end of the compressed data has
   been reached and all uncompressed output has been produced, Z_NEED_DICT if a
   preset dictionary is needed at this point, Z_DATA_ERROR if the input data was
   corrupted (input stream not conforming to the zlib format or incorrect check
   value), Z_STREAM_ERROR if the stream structure was inconsistent (for example
   next_in or next_out was Z_NULL), Z_MEM_ERROR if there was not enough memory,
   Z_BUF_ERROR if no progress is possible or if there was not enough room in the
   output buffer when Z_FINISH is used.  Note that Z_BUF_ERROR is not fatal, and
@@ skipping 81 matching lines @@
    incompatible with the version assumed by the caller (ZLIB_VERSION).  msg is
    set to null if there is no error message.  deflateInit2 does not perform any
    compression: this will be done by deflate().
 */
 
 ZEXTERN int ZEXPORT deflateSetDictionary OF((z_streamp strm,
                                              const Bytef *dictionary,
                                              uInt  dictLength));
 /*
      Initializes the compression dictionary from the given byte sequence
-   without producing any compressed output.  This function must be called
-   immediately after deflateInit, deflateInit2 or deflateReset, before any call
-   of deflate.  The compressor and decompressor must use exactly the same
-   dictionary (see inflateSetDictionary).
+   without producing any compressed output.  When using the zlib format, this
+   function must be called immediately after deflateInit, deflateInit2 or
+   deflateReset, and before any call of deflate.  When doing raw deflate, this
+   function must be called either before any call of deflate, or immediately
+   after the completion of a deflate block, i.e. after all input has been
+   consumed and all output has been delivered when using any of the flush
+   options Z_BLOCK, Z_PARTIAL_FLUSH, Z_SYNC_FLUSH, or Z_FULL_FLUSH.  The
+   compressor and decompressor must use exactly the same dictionary (see
+   inflateSetDictionary).
 
      The dictionary should consist of strings (byte sequences) that are likely
    to be encountered later in the data to be compressed, with the most commonly
    used strings preferably put towards the end of the dictionary.  Using a
    dictionary is most useful when the data to be compressed is short and can be
    predicted with good accuracy; the data can then be compressed better than
    with the default empty dictionary.
 
      Depending on the size of the compression data structures selected by
    deflateInit or deflateInit2, a part of the dictionary may in effect be
    discarded, for example if the dictionary is larger than the window size
    provided in deflateInit or deflateInit2.  Thus the strings most likely to be
    useful should be put at the end of the dictionary, not at the front.  In
    addition, the current implementation of deflate will use at most the window
    size minus 262 bytes of the provided dictionary.
 
      Upon return of this function, strm->adler is set to the adler32 value
    of the dictionary; the decompressor may later use this value to determine
    which dictionary has been used by the compressor.  (The adler32 value
    applies to the whole dictionary even if only a subset of the dictionary is
    actually used by the compressor.) If a raw deflate was requested, then the
    adler32 value is not computed and strm->adler is not set.
 
      deflateSetDictionary returns Z_OK if success, or Z_STREAM_ERROR if a
    parameter is invalid (e.g.  dictionary being Z_NULL) or the stream state is
    inconsistent (for example if deflate has already been called for this stream
-   or if the compression method is bsort).  deflateSetDictionary does not
-   perform any compression: this will be done by deflate().
+   or if not at a block boundary for raw deflate).  deflateSetDictionary does
+   not perform any compression: this will be done by deflate().
 */
 
 ZEXTERN int ZEXPORT deflateCopy OF((z_streamp dest,
                                     z_streamp source));
 /*
      Sets the destination stream as a complete copy of the source stream.
 
      This function can be useful when several compression strategies will be
    tried, for example when there are several ways of pre-processing the input
    data with a filter.  The streams that will be discarded should then be freed
@@ skipping 56 matching lines @@
    returns Z_OK on success, or Z_STREAM_ERROR for an invalid deflate stream.
  */
 
 ZEXTERN uLong ZEXPORT deflateBound OF((z_streamp strm,
                                        uLong sourceLen));
 /*
      deflateBound() returns an upper bound on the compressed size after
    deflation of sourceLen bytes.  It must be called after deflateInit() or
    deflateInit2(), and after deflateSetHeader(), if used.  This would be used
    to allocate an output buffer for deflation in a single pass, and so would be
-   called before deflate().
+   called before deflate().  If that first deflate() call is provided the
+   sourceLen input bytes, an output buffer allocated to the size returned by
+   deflateBound(), and the flush value Z_FINISH, then deflate() is guaranteed
+   to return Z_STREAM_END.  Note that it is possible for the compressed size to
+   be larger than the value returned by deflateBound() if flush options other
+   than Z_FINISH or Z_NO_FLUSH are used.
 */
 
+ZEXTERN int ZEXPORT deflatePending OF((z_streamp strm,
+                                       unsigned *pending,
+                                       int *bits));
+/*
+     deflatePending() returns the number of bytes and bits of output that have
+   been generated, but not yet provided in the available output.  The bytes not
+   provided would be due to the available output space having being consumed.
+   The number of bits of output not provided are between 0 and 7, where they
+   await more bits to join them in order to fill out a full byte.  If pending
+   or bits are Z_NULL, then those values are not set.
+
+     deflatePending returns Z_OK if success, or Z_STREAM_ERROR if the source
+   stream state was inconsistent.
+ */
+
 ZEXTERN int ZEXPORT deflatePrime OF((z_streamp strm,
                                      int bits,
                                      int value));
 /*
      deflatePrime() inserts bits in the deflate output stream.  The intent
    is that this function is used to start off the deflate output with the bits
    leftover from a previous deflate stream when appending to it.  As such, this
    function can only be used for raw deflate, and must be used before the first
    deflate() call after a deflateInit2() or deflateReset().  bits must be less
    than or equal to 16, and that many of the least significant bits of value
    will be inserted in the output.
 
-     deflatePrime returns Z_OK if success, or Z_STREAM_ERROR if the source
-   stream state was inconsistent.
+     deflatePrime returns Z_OK if success, Z_BUF_ERROR if there was not enough
+   room in the internal buffer to insert the bits, or Z_STREAM_ERROR if the
+   source stream state was inconsistent.
 */
 
 ZEXTERN int ZEXPORT deflateSetHeader OF((z_streamp strm,
                                          gz_headerp head));
 /*
      deflateSetHeader() provides gzip header information for when a gzip
    stream is requested by deflateInit2().  deflateSetHeader() may be called
    after deflateInit2() or deflateReset() and before the first call of
    deflate().  The text, time, os, extra field, name, and comment information
    in the provided gz_header structure are written to the gzip header (xflag is
@@ skipping 65 matching lines @@
 
 ZEXTERN int ZEXPORT inflateSetDictionary OF((z_streamp strm,
                                              const Bytef *dictionary,
                                              uInt  dictLength));
 /*
      Initializes the decompression dictionary from the given uncompressed byte
    sequence.  This function must be called immediately after a call of inflate,
    if that call returned Z_NEED_DICT.  The dictionary chosen by the compressor
    can be determined from the adler32 value returned by that call of inflate.
    The compressor and decompressor must use exactly the same dictionary (see
-   deflateSetDictionary).  For raw inflate, this function can be called
-   immediately after inflateInit2() or inflateReset() and before any call of
-   inflate() to set the dictionary.  The application must insure that the
-   dictionary that was used for compression is provided.
+   deflateSetDictionary).  For raw inflate, this function can be called at any
+   time to set the dictionary.  If the provided dictionary is smaller than the
+   window and there is already data in the window, then the provided dictionary
+   will amend what's there.  The application must insure that the dictionary
+   that was used for compression is provided.
 
      inflateSetDictionary returns Z_OK if success, Z_STREAM_ERROR if a
    parameter is invalid (e.g.  dictionary being Z_NULL) or the stream state is
    inconsistent, Z_DATA_ERROR if the given dictionary doesn't match the
    expected one (incorrect adler32 value).  inflateSetDictionary does not
    perform any decompression: this will be done by subsequent calls of
    inflate().
 */
 
+ZEXTERN int ZEXPORT inflateGetDictionary OF((z_streamp strm,
+                                             Bytef *dictionary,
+                                             uInt  *dictLength));
+/*
+     Returns the sliding dictionary being maintained by inflate.  dictLength is
+   set to the number of bytes in the dictionary, and that many bytes are copied
+   to dictionary.  dictionary must have enough space, where 32768 bytes is
+   always enough.  If inflateGetDictionary() is called with dictionary equal to
+   Z_NULL, then only the dictionary length is returned, and nothing is copied.
+   Similary, if dictLength is Z_NULL, then it is not set.
+
+     inflateGetDictionary returns Z_OK on success, or Z_STREAM_ERROR if the
+   stream state is inconsistent.
+*/
+
 ZEXTERN int ZEXPORT inflateSync OF((z_streamp strm));
 /*
-     Skips invalid compressed data until a full flush point (see above the
-   description of deflate with Z_FULL_FLUSH) can be found, or until all
+     Skips invalid compressed data until a possible full flush point (see above
+   for the description of deflate with Z_FULL_FLUSH) can be found, or until all
    available input is skipped.  No output is provided.
 
-     inflateSync returns Z_OK if a full flush point has been found, Z_BUF_ERROR
-   if no more input was provided, Z_DATA_ERROR if no flush point has been
-   found, or Z_STREAM_ERROR if the stream structure was inconsistent.  In the
-   success case, the application may save the current current value of total_in
-   which indicates where valid compressed data was found.  In the error case,
-   the application may repeatedly call inflateSync, providing more input each
-   time, until success or end of the input data.
+     inflateSync searches for a 00 00 FF FF pattern in the compressed data.
+   All full flush points have this pattern, but not all occurrences of this
+   pattern are full flush points.
+
+     inflateSync returns Z_OK if a possible full flush point has been found,
+   Z_BUF_ERROR if no more input was provided, Z_DATA_ERROR if no flush point
+   has been found, or Z_STREAM_ERROR if the stream structure was inconsistent.
+   In the success case, the application may save the current current value of
+   total_in which indicates where valid compressed data was found.  In the
+   error case, the application may repeatedly call inflateSync, providing more
+   input each time, until success or end of the input data.
 */
 
 ZEXTERN int ZEXPORT inflateCopy OF((z_streamp dest,
                                     z_streamp source));
 /*
      Sets the destination stream as a complete copy of the source stream.
 
      This function can be useful when randomly accessing a large stream.  The
    first pass through the stream can periodically record the inflate state,
    allowing restarting inflate at those points when randomly accessing the
@@ skipping 126 matching lines @@
    derived memory allocation routines are used.  windowBits is the base two
    logarithm of the window size, in the range 8..15.  window is a caller
    supplied buffer of that size.  Except for special applications where it is
    assured that deflate was used with small window sizes, windowBits must be 15
    and a 32K byte window must be supplied to be able to decompress general
    deflate streams.
 
      See inflateBack() for the usage of these routines.
 
      inflateBackInit will return Z_OK on success, Z_STREAM_ERROR if any of
-   the paramaters are invalid, Z_MEM_ERROR if the internal state could not be
+   the parameters are invalid, Z_MEM_ERROR if the internal state could not be
    allocated, or Z_VERSION_ERROR if the version of the library does not match
    the version of the header file.
 */
 
-typedef unsigned (*in_func) OF((void FAR *, unsigned char FAR * FAR *));
+typedef unsigned (*in_func) OF((void FAR *,
+                                z_const unsigned char FAR * FAR *));
 typedef int (*out_func) OF((void FAR *, unsigned char FAR *, unsigned));
 
 ZEXTERN int ZEXPORT inflateBack OF((z_streamp strm,
                                     in_func in, void FAR *in_desc,
                                     out_func out, void FAR *out_desc));
 /*
      inflateBack() does a raw inflate with a single call using a call-back
-   interface for input and output.  This is more efficient than inflate() for
-   file i/o applications in that it avoids copying between the output and the
-   sliding window by simply making the window itself the output buffer.  This
-   function trusts the application to not change the output buffer passed by
-   the output function, at least until inflateBack() returns.
+   interface for input and output.  This is potentially more efficient than
+   inflate() for file i/o applications, in that it avoids copying between the
+   output and the sliding window by simply making the window itself the output
+   buffer.  inflate() can be faster on modern CPUs when used with large
+   buffers.  inflateBack() trusts the application to not change the output
+   buffer passed by the output function, at least until inflateBack() returns.
 
      inflateBackInit() must be called first to allocate the internal state
    and to initialize the state with the user-provided window buffer.
    inflateBack() may then be used multiple times to inflate a complete, raw
    deflate stream with each call.  inflateBackEnd() is then called to free the
    allocated state.
 
      A raw deflate stream is one with no zlib or gzip header or trailer.
    This routine would normally be used in a utility that reads zip or gzip
    files and writes out uncompressed files.  The utility would decode the
@@ skipping 88 matching lines @@
 
     The sprintf variant used by gzprintf (zero is best):
      24: 0 = vs*, 1 = s* -- 1 means limited to 20 arguments after the format
      25: 0 = *nprintf, 1 = *printf -- 1 means gzprintf() not secure!
      26: 0 = returns value, 1 = void -- 1 means inferred string length returned
 
     Remainder:
      27-31: 0 (reserved)
  */
 
+#ifndef Z_SOLO
 
                         /* utility functions */
 
 /*
      The following utility functions are implemented on top of the basic
    stream-oriented functions.  To simplify the interface, some default options
    are assumed (compression level and memory usage, standard memory allocation
    functions).  The source code of these utility functions can be modified if
    you need special options.
 */
@@ skipping 41 matching lines @@
      Decompresses the source buffer into the destination buffer.  sourceLen is
    the byte length of the source buffer.  Upon entry, destLen is the total size
    of the destination buffer, which must be large enough to hold the entire
    uncompressed data.  (The size of the uncompressed data must have been saved
    previously by the compressor and transmitted to the decompressor by some
    mechanism outside the scope of this compression library.) Upon exit, destLen
    is the actual size of the uncompressed buffer.
 
      uncompress returns Z_OK if success, Z_MEM_ERROR if there was not
    enough memory, Z_BUF_ERROR if there was not enough room in the output
-   buffer, or Z_DATA_ERROR if the input data was corrupted or incomplete.
+   buffer, or Z_DATA_ERROR if the input data was corrupted or incomplete.  In
+   the case where there is not enough room, uncompress() will fill the output
+   buffer with the uncompressed data up to that point.
 */
 
-
                         /* gzip file access functions */
 
 /*
      This library supports reading and writing files in gzip (.gz) format with
    an interface similar to that of stdio, using the functions that start with
    "gz".  The gzip format is different from the zlib format.  gzip is a gzip
    wrapper, documented in RFC 1952, wrapped around a deflate stream.
 */
 
-typedef voidp gzFile;       /* opaque gzip file descriptor */
+typedef struct gzFile_s *gzFile;    /* semi-opaque gzip file descriptor */
 
 /*
 ZEXTERN gzFile ZEXPORT gzopen OF((const char *path, const char *mode));
 
      Opens a gzip (.gz) file for reading or writing.  The mode parameter is as
    in fopen ("rb" or "wb") but can also include a compression level ("wb9") or
    a strategy: 'f' for filtered data as in "wb6f", 'h' for Huffman-only
    compression as in "wb1h", 'R' for run-length encoding as in "wb1R", or 'F'
    for fixed code compression as in "wb9F".  (See the description of
-   deflateInit2 for more information about the strategy parameter.) Also "a"
-   can be used instead of "w" to request that the gzip stream that will be
-   written be appended to the file.  "+" will result in an error, since reading
-   and writing to the same gzip file is not supported.
+   deflateInit2 for more information about the strategy parameter.)  'T' will
+   request transparent writing or appending with no compression and not using
+   the gzip format.
+
+     "a" can be used instead of "w" to request that the gzip stream that will
+   be written be appended to the file.  "+" will result in an error, since
+   reading and writing to the same gzip file is not supported.  The addition of
+   "x" when writing will create the file exclusively, which fails if the file
+   already exists.  On systems that support it, the addition of "e" when
+   reading or writing will set the flag to close the file on an execve() call.
+
+     These functions, as well as gzip, will read and decode a sequence of gzip
+   streams in a file.  The append function of gzopen() can be used to create
+   such a file.  (Also see gzflush() for another way to do this.)  When
+   appending, gzopen does not test whether the file begins with a gzip stream,
+   nor does it look for the end of the gzip streams to begin appending.  gzopen
+   will simply append a gzip stream to the existing file.
 
      gzopen can be used to read a file which is not in gzip format; in this
-   case gzread will directly read from the file without decompression.
+   case gzread will directly read from the file without decompression.  When
+   reading, this will be detected automatically by looking for the magic two-
+   byte gzip header.
 
      gzopen returns NULL if the file could not be opened, if there was
    insufficient memory to allocate the gzFile state, or if an invalid mode was
    specified (an 'r', 'w', or 'a' was not provided, or '+' was provided).
    errno can be checked to determine if the reason gzopen failed was that the
    file could not be opened.
 */
 
 ZEXTERN gzFile ZEXPORT gzdopen OF((int fd, const char *mode));
 /*
      gzdopen associates a gzFile with the file descriptor fd.  File descriptors
    are obtained from calls like open, dup, creat, pipe or fileno (if the file
    has been previously opened with fopen).  The mode parameter is as in gzopen.
 
      The next call of gzclose on the returned gzFile will also close the file
    descriptor fd, just like fclose(fdopen(fd, mode)) closes the file descriptor
    fd.  If you want to keep fd open, use fd = dup(fd_keep); gz = gzdopen(fd,
    mode);.  The duplicated descriptor should be saved to avoid a leak, since
-   gzdopen does not close fd if it fails.
+   gzdopen does not close fd if it fails.  If you are using fileno() to get the
+   file descriptor from a FILE *, then you will have to use dup() to avoid
+   double-close()ing the file descriptor.  Both gzclose() and fclose() will
+   close the associated file descriptor, so they need to have different file
+   descriptors.
 
      gzdopen returns NULL if there was insufficient memory to allocate the
    gzFile state, if an invalid mode was specified (an 'r', 'w', or 'a' was not
    provided, or '+' was provided), or if fd is -1.  The file descriptor is not
    used until the next gz* read, write, seek, or close operation, so gzdopen
    will not detect if fd is invalid (unless fd is -1).
 */
 
 ZEXTERN int ZEXPORT gzbuffer OF((gzFile file, unsigned size));
 /*
@@ skipping 17 matching lines @@
      Dynamically update the compression level or strategy.  See the description
    of deflateInit2 for the meaning of these parameters.
 
      gzsetparams returns Z_OK if success, or Z_STREAM_ERROR if the file was not
    opened for writing.
 */
 
 ZEXTERN int ZEXPORT gzread OF((gzFile file, voidp buf, unsigned len));
 /*
      Reads the given number of uncompressed bytes from the compressed file.  If
-   the input file was not in gzip format, gzread copies the given number of
-   bytes into the buffer.
+   the input file is not in gzip format, gzread copies the given number of
+   bytes into the buffer directly from the file.
 
      After reaching the end of a gzip stream in the input, gzread will continue
-   to read, looking for another gzip stream, or failing that, reading the rest
-   of the input file directly without decompression.  The entire input file
-   will be read if gzread is called until it returns less than the requested
-   len.
+   to read, looking for another gzip stream.  Any number of gzip streams may be
+   concatenated in the input file, and will all be decompressed by gzread().
+   If something other than a gzip stream is encountered after a gzip stream,
+   that remaining trailing garbage is ignored (and no error is returned).
+
+     gzread can be used to read a gzip file that is being concurrently written.
+   Upon reaching the end of the input, gzread will return with the available
+   data.  If the error code returned by gzerror is Z_OK or Z_BUF_ERROR, then
+   gzclearerr can be used to clear the end of file indicator in order to permit
+   gzread to be tried again.  Z_OK indicates that a gzip stream was completed
+   on the last gzread.  Z_BUF_ERROR indicates that the input file ended in the
+   middle of a gzip stream.  Note that gzread does not return -1 in the event
+   of an incomplete gzip stream.  This error is deferred until gzclose(), which
+   will return Z_BUF_ERROR if the last gzread ended in the middle of a gzip
+   stream.  Alternatively, gzerror can be used before gzclose to detect this
+   case.
 
      gzread returns the number of uncompressed bytes actually read, less than
    len for end of file, or -1 for error.
 */
 
 ZEXTERN int ZEXPORT gzwrite OF((gzFile file,
                                 voidpc buf, unsigned len));
 /*
      Writes the given number of uncompressed bytes into the compressed file.
    gzwrite returns the number of uncompressed bytes written or 0 in case of
    error.
 */
 
-ZEXTERN int ZEXPORTVA gzprintf OF((gzFile file, const char *format, ...));
+ZEXTERN int ZEXPORTVA gzprintf Z_ARG((gzFile file, const char *format, ...));
 /*
      Converts, formats, and writes the arguments to the compressed file under
    control of the format string, as in fprintf.  gzprintf returns the number of
    uncompressed bytes actually written, or 0 in case of error.  The number of
    uncompressed bytes written is limited to 8191, or one less than the buffer
    size given to gzbuffer().  The caller should assure that this limit is not
    exceeded.  If it is exceeded, then gzprintf() will return an error (0) with
    nothing written.  In this case, there may also be a buffer overflow with
    unpredictable consequences, which is possible only if zlib was compiled with
    the insecure functions sprintf() or vsprintf() because the secure snprintf()
@@ skipping 24 matching lines @@
 
 ZEXTERN int ZEXPORT gzputc OF((gzFile file, int c));
 /*
      Writes c, converted to an unsigned char, into the compressed file.  gzputc
    returns the value that was written, or -1 in case of error.
 */
 
 ZEXTERN int ZEXPORT gzgetc OF((gzFile file));
 /*
      Reads one byte from the compressed file.  gzgetc returns this byte or -1
-   in case of end of file or error.
+   in case of end of file or error.  This is implemented as a macro for speed.
+   As such, it does not do all of the checking the other functions do.  I.e.
+   it does not check to see if file is NULL, nor whether the structure file
+   points to has been clobbered or not.
 */
 
 ZEXTERN int ZEXPORT gzungetc OF((int c, gzFile file));
 /*
      Push one character back onto the stream to be read as the first character
    on the next read.  At least one character of push-back is allowed.
    gzungetc() returns the character pushed, or -1 on failure.  gzungetc() will
    fail if c is -1, and may fail if a character has been pushed but not read
    yet.  If gzungetc is used immediately after gzopen or gzdopen, at least the
    output buffer size of pushed characters is allowed.  (See gzbuffer above.)
@@ skipping 75 matching lines @@
    is an exact multiple of the buffer size.
 
      If gzeof() returns true, then the read functions will return no more data,
    unless the end-of-file indicator is reset by gzclearerr() and the input file
    has grown since the previous end of file was detected.
 */
 
 ZEXTERN int ZEXPORT gzdirect OF((gzFile file));
 /*
      Returns true (1) if file is being copied directly while reading, or false
-   (0) if file is a gzip stream being decompressed.  This state can change from
-   false to true while reading the input file if the end of a gzip stream is
-   reached, but is followed by data that is not another gzip stream.
+   (0) if file is a gzip stream being decompressed.
 
      If the input file is empty, gzdirect() will return true, since the input
    does not contain a gzip stream.
 
      If gzdirect() is used immediately after gzopen() or gzdopen() it will
    cause buffers to be allocated to allow reading the file to determine if it
    is a gzip file.  Therefore if gzbuffer() is used, it should be called before
    gzdirect().
+
+     When writing, gzdirect() returns true (1) if transparent writing was
+   requested ("wT" for the gzopen() mode), or false (0) otherwise.  (Note:
+   gzdirect() is not needed when writing.  Transparent writing must be
+   explicitly requested, so the application already knows the answer.  When
+   linking statically, using gzdirect() will include all of the zlib code for
+   gzip file reading and decompression, which may not be desired.)
 */
 
 ZEXTERN int ZEXPORT    gzclose OF((gzFile file));
 /*
      Flushes all pending output if necessary, closes the compressed file and
    deallocates the (de)compression state.  Note that once file is closed, you
    cannot call gzerror with file, since its structures have been deallocated.
    gzclose must not be called more than once on the same file, just as free
    must not be called more than once on the same allocation.
 
      gzclose will return Z_STREAM_ERROR if file is not valid, Z_ERRNO on a
-   file operation error, or Z_OK on success.
+   file operation error, Z_MEM_ERROR if out of memory, Z_BUF_ERROR if the
+   last read ended in the middle of a gzip stream, or Z_OK on success.
 */
 
 ZEXTERN int ZEXPORT gzclose_r OF((gzFile file));
 ZEXTERN int ZEXPORT gzclose_w OF((gzFile file));
 /*
      Same as gzclose(), but gzclose_r() is only for use when reading, and
    gzclose_w() is only for use when writing or appending.  The advantage to
    using these instead of gzclose() is that they avoid linking in zlib
    compression or decompression code that is not used when only reading or only
    writing respectively.  If gzclose() is used, then both compression and
@@ skipping 17 matching lines @@
    functions above that do not distinguish those cases in their return values.
 */
 
 ZEXTERN void ZEXPORT gzclearerr OF((gzFile file));
 /*
      Clears the error and end-of-file flags for file.  This is analogous to the
    clearerr() function in stdio.  This is useful for continuing to read a gzip
    file that is being written concurrently.
 */
 
+#endif /* !Z_SOLO */
 
                         /* checksum functions */
 
 /*
      These functions are not related to compression but are exported
    anyway because they might be useful in applications using the compression
    library.
 */
 
 ZEXTERN uLong ZEXPORT adler32 OF((uLong adler, const Bytef *buf, uInt len));
@@ skipping 15 matching lines @@
      if (adler != original_adler) error();
 */
 
 /*
 ZEXTERN uLong ZEXPORT adler32_combine OF((uLong adler1, uLong adler2,
                                           z_off_t len2));
 
      Combine two Adler-32 checksums into one.  For two sequences of bytes, seq1
    and seq2 with lengths len1 and len2, Adler-32 checksums were calculated for
    each, adler1 and adler2.  adler32_combine() returns the Adler-32 checksum of
-   seq1 and seq2 concatenated, requiring only adler1, adler2, and len2.
+   seq1 and seq2 concatenated, requiring only adler1, adler2, and len2.  Note
+   that the z_off_t type (like off_t) is a signed integer.  If len2 is
+   negative, the result has no meaning or utility.
 */
 
 ZEXTERN uLong ZEXPORT crc32   OF((uLong crc, const Bytef *buf, uInt len));
 /*
      Update a running CRC-32 with the bytes buf[0..len-1] and return the
    updated CRC-32.  If buf is Z_NULL, this function returns the required
-   initial value for the for the crc.  Pre- and post-conditioning (one's
-   complement) is performed within this function so it shouldn't be done by the
-   application.
+   initial value for the crc.  Pre- and post-conditioning (one's complement) is
+   performed within this function so it shouldn't be done by the application.
 
    Usage example:
 
      uLong crc = crc32(0L, Z_NULL, 0);
 
      while (read_buffer(buffer, length) != EOF) {
        crc = crc32(crc, buffer, length);
      }
      if (crc != original_crc) error();
 */
@@ skipping 22 matching lines @@
                                       int windowBits, int memLevel,
                                       int strategy, const char *version,
                                       int stream_size));
 ZEXTERN int ZEXPORT inflateInit2_ OF((z_streamp strm, int  windowBits,
                                       const char *version, int stream_size));
 ZEXTERN int ZEXPORT inflateBackInit_ OF((z_streamp strm, int windowBits,
                                          unsigned char FAR *window,
                                          const char *version,
                                          int stream_size));
 #define deflateInit(strm, level) \
-        deflateInit_((strm), (level),       ZLIB_VERSION, sizeof(z_stream))
+        deflateInit_((strm), (level), ZLIB_VERSION, (int)sizeof(z_stream))
 #define inflateInit(strm) \
-        inflateInit_((strm),                ZLIB_VERSION, sizeof(z_stream))
+        inflateInit_((strm), ZLIB_VERSION, (int)sizeof(z_stream))
 #define deflateInit2(strm, level, method, windowBits, memLevel, strategy) \
         deflateInit2_((strm),(level),(method),(windowBits),(memLevel),\
-                      (strategy),           ZLIB_VERSION, sizeof(z_stream))
+                      (strategy), ZLIB_VERSION, (int)sizeof(z_stream))
 #define inflateInit2(strm, windowBits) \
-        inflateInit2_((strm), (windowBits), ZLIB_VERSION, sizeof(z_stream))
+        inflateInit2_((strm), (windowBits), ZLIB_VERSION, \
+                      (int)sizeof(z_stream))
 #define inflateBackInit(strm, windowBits, window) \
         inflateBackInit_((strm), (windowBits), (window), \
-                                            ZLIB_VERSION, sizeof(z_stream))
+                      ZLIB_VERSION, (int)sizeof(z_stream))
+
+#ifndef Z_SOLO
+
+/* gzgetc() macro and its supporting function and exposed data structure.  Note
+ * that the real internal state is much larger than the exposed structure.
+ * This abbreviated structure exposes just enough for the gzgetc() macro.  The
+ * user should not mess with these exposed elements, since their names or
+ * behavior could change in the future, perhaps even capriciously.  They can
+ * only be used by the gzgetc() macro.  You have been warned.
+ */
+struct gzFile_s {
+    unsigned have;
+    unsigned char *next;
+    z_off64_t pos;
+};
+ZEXTERN int ZEXPORT gzgetc_ OF((gzFile file));  /* backward compatibility */
+#ifdef Z_PREFIX_SET
+#  undef z_gzgetc
+#  define z_gzgetc(g) \
+          ((g)->have ? ((g)->have--, (g)->pos++, *((g)->next)++) : gzgetc(g))
+#else
+#  ifdef MOZZCONF_H
+#    undef gzgetc
+#    define gzgetc(g) \
+          ((g)->have ? ((g)->have--, (g)->pos++, *((g)->next)++) : MOZ_Z_gzgetc(g))
+#  else
+#    define gzgetc(g) \
+          ((g)->have ? ((g)->have--, (g)->pos++, *((g)->next)++) : gzgetc(g))
+#  endif
+#endif
 
 /* provide 64-bit offset functions if _LARGEFILE64_SOURCE defined, and/or
  * change the regular functions to 64 bits if _FILE_OFFSET_BITS is 64 (if
  * both are true, the application gets the *64 functions, and the regular
  * functions are changed to 64 bits) -- in case these are set on systems
  * without large file support, _LFS64_LARGEFILE must also be true
  */
-#if defined(_LARGEFILE64_SOURCE) && _LFS64_LARGEFILE-0
+#ifdef Z_LARGE64
    ZEXTERN gzFile ZEXPORT gzopen64 OF((const char *, const char *));
    ZEXTERN z_off64_t ZEXPORT gzseek64 OF((gzFile, z_off64_t, int));
    ZEXTERN z_off64_t ZEXPORT gztell64 OF((gzFile));
    ZEXTERN z_off64_t ZEXPORT gzoffset64 OF((gzFile));
    ZEXTERN uLong ZEXPORT adler32_combine64 OF((uLong, uLong, z_off64_t));
    ZEXTERN uLong ZEXPORT crc32_combine64 OF((uLong, uLong, z_off64_t));
 #endif
 
-#if !defined(ZLIB_INTERNAL) && _FILE_OFFSET_BITS-0 == 64 && _LFS64_LARGEFILE-0
-#  ifdef gzopen
-#    undef gzopen
+#if !defined(ZLIB_INTERNAL) && defined(Z_WANT64)
+#  ifdef Z_PREFIX_SET
+#    define z_gzopen z_gzopen64
+#    define z_gzseek z_gzseek64
+#    define z_gztell z_gztell64
+#    define z_gzoffset z_gzoffset64
+#    define z_adler32_combine z_adler32_combine64
+#    define z_crc32_combine z_crc32_combine64
+#  else
+#    ifdef gzopen
+#      undef gzopen
+#    endif
+#    define gzopen gzopen64
+#    ifdef gzseek
+#      undef gzseek
+#    endif
+#    define gzseek gzseek64
+#    ifdef gztell
+#      undef gztell
+#    endif
+#    define gztell gztell64
+#    ifdef gzoffset
+#      undef gzoffset
+#    endif
+#    define gzoffset gzoffset64
+#    ifdef adler32_combine
+#      undef adler32_combine
+#    endif
+#    define adler32_combine adler32_combine64
+#    ifdef crc32_combine
+#      undef crc32_combine
+#    endif
+#    define crc32_combine crc32_combine64
 #  endif
-#  define gzopen gzopen64
-#  ifdef gzseek
-#    undef gzseek
-#  endif
-#  define gzseek gzseek64
-#  ifdef gztell
-#    undef gztell
-#  endif
-#  define gztell gztell64
-#  ifdef gzoffset
-#    undef gzoffset
-#  endif
-#  define gzoffset gzoffset64
-#  ifdef adler32_combine
-#    undef adler32_combine
-#  endif
-#  define adler32_combine adler32_combine64
-#  ifdef crc32_combine
-#    undef crc32_combine
-#  endif
-#  define crc32_combine crc32_combine64
-#  ifdef _LARGEFILE64_SOURCE
+#  ifndef Z_LARGE64
      ZEXTERN gzFile ZEXPORT gzopen64 OF((const char *, const char *));
      ZEXTERN z_off_t ZEXPORT gzseek64 OF((gzFile, z_off_t, int));
      ZEXTERN z_off_t ZEXPORT gztell64 OF((gzFile));
      ZEXTERN z_off_t ZEXPORT gzoffset64 OF((gzFile));
      ZEXTERN uLong ZEXPORT adler32_combine64 OF((uLong, uLong, z_off_t));
      ZEXTERN uLong ZEXPORT crc32_combine64 OF((uLong, uLong, z_off_t));
 #  else
      ZEXTERN gzFile ZEXPORT gzopen OF((const char *, const char *));
      ZEXTERN z_off_t ZEXPORT gzseek OF((gzFile, z_off_t, int));
      ZEXTERN z_off_t ZEXPORT gztell OF((gzFile));
      ZEXTERN z_off_t ZEXPORT gzoffset OF((gzFile));
      ZEXTERN uLong ZEXPORT adler32_combine OF((uLong, uLong, z_off_t));
      ZEXTERN uLong ZEXPORT crc32_combine OF((uLong, uLong, z_off_t));
 #  endif
 #else
    ZEXTERN gzFile ZEXPORT gzopen OF((const char *, const char *));
    ZEXTERN z_off_t ZEXPORT gzseek OF((gzFile, z_off_t, int));
    ZEXTERN z_off_t ZEXPORT gztell OF((gzFile));
    ZEXTERN z_off_t ZEXPORT gzoffset OF((gzFile));
    ZEXTERN uLong ZEXPORT adler32_combine OF((uLong, uLong, z_off_t));
    ZEXTERN uLong ZEXPORT crc32_combine OF((uLong, uLong, z_off_t));
 #endif
 
+#else /* Z_SOLO */
+
+   ZEXTERN uLong ZEXPORT adler32_combine OF((uLong, uLong, z_off_t));
+   ZEXTERN uLong ZEXPORT crc32_combine OF((uLong, uLong, z_off_t));
+
+#endif /* !Z_SOLO */
+
 /* hack for buggy compilers */
 #if !defined(ZUTIL_H) && !defined(NO_DUMMY_DECL)
     struct internal_state {int dummy;};
 #endif
 
 /* undocumented functions */
 ZEXTERN const char   * ZEXPORT zError           OF((int));
 ZEXTERN int            ZEXPORT inflateSyncPoint OF((z_streamp));
-ZEXTERN const uLongf * ZEXPORT get_crc_table    OF((void));
+ZEXTERN const z_crc_t FAR * ZEXPORT get_crc_table    OF((void));
 ZEXTERN int            ZEXPORT inflateUndermine OF((z_streamp, int));
+ZEXTERN int            ZEXPORT inflateResetKeep OF((z_streamp));
+ZEXTERN int            ZEXPORT deflateResetKeep OF((z_streamp));
+#if defined(_WIN32) && !defined(Z_SOLO)
+ZEXTERN gzFile         ZEXPORT gzopen_w OF((const wchar_t *path,
+                                            const char *mode));
+#endif
+#if defined(STDC) || defined(Z_HAVE_STDARG_H)
+#  ifndef Z_SOLO
+ZEXTERN int            ZEXPORTVA gzvprintf Z_ARG((gzFile file,
+                                                  const char *format,
+                                                  va_list va));
+#  endif
+#endif
 
 #ifdef __cplusplus
 }
 #endif
 
 #endif /* ZLIB_H */