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