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132
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1 /* zlib.h -- interface of the 'zlib' general purpose compression library
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2 version 1.2.3, July 18th, 2005
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3
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4 Copyright (C) 1995-2005 Jean-loup Gailly and Mark Adler
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5
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6 This software is provided 'as-is', without any express or implied
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7 warranty. In no event will the authors be held liable for any damages
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8 arising from the use of this software.
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9
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10 Permission is granted to anyone to use this software for any purpose,
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11 including commercial applications, and to alter it and redistribute it
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12 freely, subject to the following restrictions:
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13
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14 1. The origin of this software must not be misrepresented; you must not
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15 claim that you wrote the original software. If you use this software
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16 in a product, an acknowledgment in the product documentation would be
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17 appreciated but is not required.
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18 2. Altered source versions must be plainly marked as such, and must not be
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19 misrepresented as being the original software.
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20 3. This notice may not be removed or altered from any source distribution.
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21
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22 Jean-loup Gailly Mark Adler
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23 jloup@gzip.org madler@alumni.caltech.edu
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24
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25
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26 The data format used by the zlib library is described by RFCs (Request for
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27 Comments) 1950 to 1952 in the files http://www.ietf.org/rfc/rfc1950.txt
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28 (zlib format), rfc1951.txt (deflate format) and rfc1952.txt (gzip format).
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29 */
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30
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31 module tango.io.compress.c.zlib;
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32
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33 extern (C):
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34
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35 const char* ZLIB_VERSION = "1.2.3";
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36 const uint ZLIB_VERNUM = 0x1230;
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37
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38 /*
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39 The 'zlib' compression library provides in-memory compression and
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40 decompression functions, including integrity checks of the uncompressed
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41 data. This version of the library supports only one compression method
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42 (deflation) but other algorithms will be added later and will have the same
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43 stream interface.
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44
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45 Compression can be done in a single step if the buffers are large
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46 enough (for example if an input file is mmap'ed), or can be done by
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47 repeated calls of the compression function. In the latter case, the
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48 application must provide more input and/or consume the output
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49 (providing more output space) before each call.
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50
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51 The compressed data format used by default by the in-memory functions is
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52 the zlib format, which is a zlib wrapper documented in RFC 1950, wrapped
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53 around a deflate stream, which is itself documented in RFC 1951.
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54
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55 The library also supports reading and writing files in gzip (.gz) format
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56 with an interface similar to that of stdio using the functions that start
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57 with "gz". The gzip format is different from the zlib format. gzip is a
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58 gzip wrapper, documented in RFC 1952, wrapped around a deflate stream.
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59
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60 This library can optionally read and write gzip streams in memory as well.
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61
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62 The zlib format was designed to be compact and fast for use in memory
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63 and on communications channels. The gzip format was designed for single-
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64 file compression on file systems, has a larger header than zlib to maintain
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65 directory information, and uses a different, slower check method than zlib.
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66
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67 The library does not install any signal handler. The decoder checks
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68 the consistency of the compressed data, so the library should never
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69 crash even in case of corrupted input.
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70 */
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71
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72 private
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73 {
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74 import tango.stdc.config : c_long, c_ulong;
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75
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76 version( Posix )
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77 {
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78 import tango.stdc.posix.sys.types : z_off_t = off_t;
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79 }
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80 else
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81 {
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82 alias c_long z_off_t;
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83 }
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84
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85 alias ubyte Byte;
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86 alias uint uInt;
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87 alias c_ulong uLong;
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88
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89 alias Byte Bytef;
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90 alias char charf;
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91 alias int intf;
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92 alias uInt uIntf;
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93 alias uLong uLongf;
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94
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95 alias void* voidpc; // TODO: normally const
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96 alias void* voidpf;
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97 alias void* voidp;
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98
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99 alias voidpf function(voidpf opaque, uInt items, uInt size) alloc_func;
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100 alias void function(voidpf opaque, voidpf address) free_func;
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101
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102 struct internal_state {}
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103 }
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104
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105 struct z_stream
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106 {
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107 Bytef* next_in; /* next input byte */
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108 uInt avail_in; /* number of bytes available at next_in */
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109 uLong total_in; /* total nb of input bytes read so far */
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110
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111 Bytef* next_out; /* next output byte should be put there */
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112 uInt avail_out; /* remaining free space at next_out */
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113 uLong total_out; /* total nb of bytes output so far */
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114
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115 char* msg; /* last error message, NULL if no error */
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116 internal_state* state; /* not visible by applications */
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117
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118 alloc_func zalloc; /* used to allocate the internal state */
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119 free_func zfree; /* used to free the internal state */
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120 voidpf opaque; /* private data object passed to zalloc and zfree */
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121
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122 int data_type; /* best guess about the data type: binary or text */
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123 uLong adler; /* adler32 value of the uncompressed data */
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124 uLong reserved; /* reserved for future use */
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125 }
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126
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127 alias z_stream* z_streamp;
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128
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129 /*
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130 gzip header information passed to and from zlib routines. See RFC 1952
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131 for more details on the meanings of these fields.
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132 */
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133 struct gz_header
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134 {
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135 int text; /* true if compressed data believed to be text */
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136 uLong time; /* modification time */
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137 int xflags; /* extra flags (not used when writing a gzip file) */
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138 int os; /* operating system */
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139 Bytef* extra; /* pointer to extra field or Z_NULL if none */
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140 uInt extra_len; /* extra field length (valid if extra != Z_NULL) */
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141 uInt extra_max; /* space at extra (only when reading header) */
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142 Bytef* name; /* pointer to zero-terminated file name or Z_NULL */
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143 uInt name_max; /* space at name (only when reading header) */
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144 Bytef* comment; /* pointer to zero-terminated comment or Z_NULL */
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145 uInt comm_max; /* space at comment (only when reading header) */
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146 int hcrc; /* true if there was or will be a header crc */
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147 int done; /* true when done reading gzip header (not used
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148 when writing a gzip file) */
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149 }
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150
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151 alias gz_header* gz_headerp;
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152
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153 /*
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154 The application must update next_in and avail_in when avail_in has
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155 dropped to zero. It must update next_out and avail_out when avail_out
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156 has dropped to zero. The application must initialize zalloc, zfree and
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157 opaque before calling the init function. All other fields are set by the
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158 compression library and must not be updated by the application.
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159
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160 The opaque value provided by the application will be passed as the first
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161 parameter for calls of zalloc and zfree. This can be useful for custom
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162 memory management. The compression library attaches no meaning to the
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163 opaque value.
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164
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165 zalloc must return Z_NULL if there is not enough memory for the object.
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166 If zlib is used in a multi-threaded application, zalloc and zfree must be
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167 thread safe.
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168
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169 On 16-bit systems, the functions zalloc and zfree must be able to allocate
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170 exactly 65536 bytes, but will not be required to allocate more than this
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171 if the symbol MAXSEG_64K is defined (see zconf.h). WARNING: On MSDOS,
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172 pointers returned by zalloc for objects of exactly 65536 bytes *must*
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173 have their offset normalized to zero. The default allocation function
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174 provided by this library ensures this (see zutil.c). To reduce memory
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175 requirements and avoid any allocation of 64K objects, at the expense of
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176 compression ratio, compile the library with -DMAX_WBITS=14 (see zconf.h).
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177
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178 The fields total_in and total_out can be used for statistics or
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179 progress reports. After compression, total_in holds the total size of
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180 the uncompressed data and may be saved for use in the decompressor
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181 (particularly if the decompressor wants to decompress everything in
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182 a single step).
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183 */
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184
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185 /* constants */
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186
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187 enum
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188 {
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189 Z_NO_FLUSH = 0,
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190 Z_PARTIAL_FLUSH = 1, /* will be removed, use Z_SYNC_FLUSH instead */
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191 Z_SYNC_FLUSH = 2,
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192 Z_FULL_FLUSH = 3,
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193 Z_FINISH = 4,
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194 Z_BLOCK = 5,
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195 }
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196 /* Allowed flush values; see deflate() and inflate() below for details */
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197
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198 enum
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199 {
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200 Z_OK = 0,
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201 Z_STREAM_END = 1,
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202 Z_NEED_DICT = 2,
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203 Z_ERRNO = -1,
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204 Z_STREAM_ERROR = -2,
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205 Z_DATA_ERROR = -3,
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206 Z_MEM_ERROR = -4,
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207 Z_BUF_ERROR = -5,
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208 Z_VERSION_ERROR = -6,
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209 }
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210 /* Return codes for the compression/decompression functions. Negative
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211 * values are errors, positive values are used for special but normal events.
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212 */
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213
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214 enum
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215 {
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216 Z_NO_COMPRESSION = 0,
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217 Z_BEST_SPEED = 1,
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218 Z_BEST_COMPRESSION = 9,
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219 Z_DEFAULT_COMPRESSION = -1,
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220 }
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221 /* compression levels */
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222
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223 enum
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224 {
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225 Z_FILTERED = 1,
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226 Z_HUFFMAN_ONLY = 2,
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227 Z_RLE = 3,
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228 Z_FIXED = 4,
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229 Z_DEFAULT_STRATEGY = 0,
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230 }
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231 /* compression strategy; see deflateInit2() below for details */
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232
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233 enum
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234 {
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235 Z_BINARY = 0,
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236 Z_TEXT = 1,
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237 Z_ASCII = Z_TEXT, /* for compatibility with 1.2.2 and earlier */
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238 Z_UNKNOWN = 2,
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239 }
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240 /* Possible values of the data_type field (though see inflate()) */
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241
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242 enum
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243 {
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244 Z_DEFLATED = 8,
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245 }
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246 /* The deflate compression method (the only one supported in this version) */
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247
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248 const Z_NULL = null; /* for initializing zalloc, zfree, opaque */
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249
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250 alias zlibVersion zlib_version;
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251 /* for compatibility with versions < 1.0.2 */
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252
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253 /* basic functions */
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254
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255 char* zlibVersion();
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256 /* The application can compare zlibVersion and ZLIB_VERSION for consistency.
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257 If the first character differs, the library code actually used is
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258 not compatible with the zlib.h header file used by the application.
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259 This check is automatically made by deflateInit and inflateInit.
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260 */
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261
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262 /*
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263 int deflateInit (z_streamp strm, int level);
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264
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265 Initializes the internal stream state for compression. The fields
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266 zalloc, zfree and opaque must be initialized before by the caller.
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267 If zalloc and zfree are set to Z_NULL, deflateInit updates them to
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268 use default allocation functions.
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269
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270 The compression level must be Z_DEFAULT_COMPRESSION, or between 0 and 9:
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271 1 gives best speed, 9 gives best compression, 0 gives no compression at
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272 all (the input data is simply copied a block at a time).
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273 Z_DEFAULT_COMPRESSION requests a default compromise between speed and
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274 compression (currently equivalent to level 6).
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275
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276 deflateInit returns Z_OK if success, Z_MEM_ERROR if there was not
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277 enough memory, Z_STREAM_ERROR if level is not a valid compression level,
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278 Z_VERSION_ERROR if the zlib library version (zlib_version) is incompatible
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279 with the version assumed by the caller (ZLIB_VERSION).
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280 msg is set to null if there is no error message. deflateInit does not
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281 perform any compression: this will be done by deflate().
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282 */
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283
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284
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285 int deflate(z_streamp strm, int flush);
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286 /*
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287 deflate compresses as much data as possible, and stops when the input
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288 buffer becomes empty or the output buffer becomes full. It may introduce some
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289 output latency (reading input without producing any output) except when
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290 forced to flush.
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291
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292 The detailed semantics are as follows. deflate performs one or both of the
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293 following actions:
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294
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295 - Compress more input starting at next_in and update next_in and avail_in
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296 accordingly. If not all input can be processed (because there is not
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297 enough room in the output buffer), next_in and avail_in are updated and
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298 processing will resume at this point for the next call of deflate().
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299
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300 - Provide more output starting at next_out and update next_out and avail_out
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301 accordingly. This action is forced if the parameter flush is non zero.
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302 Forcing flush frequently degrades the compression ratio, so this parameter
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303 should be set only when necessary (in interactive applications).
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304 Some output may be provided even if flush is not set.
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305
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306 Before the call of deflate(), the application should ensure that at least
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307 one of the actions is possible, by providing more input and/or consuming
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308 more output, and updating avail_in or avail_out accordingly; avail_out
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309 should never be zero before the call. The application can consume the
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310 compressed output when it wants, for example when the output buffer is full
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311 (avail_out == 0), or after each call of deflate(). If deflate returns Z_OK
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312 and with zero avail_out, it must be called again after making room in the
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313 output buffer because there might be more output pending.
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314
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315 Normally the parameter flush is set to Z_NO_FLUSH, which allows deflate to
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316 decide how much data to accumualte before producing output, in order to
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317 maximize compression.
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318
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319 If the parameter flush is set to Z_SYNC_FLUSH, all pending output is
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320 flushed to the output buffer and the output is aligned on a byte boundary, so
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321 that the decompressor can get all input data available so far. (In particular
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322 avail_in is zero after the call if enough output space has been provided
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323 before the call.) Flushing may degrade compression for some compression
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324 algorithms and so it should be used only when necessary.
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325
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326 If flush is set to Z_FULL_FLUSH, all output is flushed as with
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327 Z_SYNC_FLUSH, and the compression state is reset so that decompression can
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328 restart from this point if previous compressed data has been damaged or if
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329 random access is desired. Using Z_FULL_FLUSH too often can seriously degrade
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330 compression.
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331
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332 If deflate returns with avail_out == 0, this function must be called again
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333 with the same value of the flush parameter and more output space (updated
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334 avail_out), until the flush is complete (deflate returns with non-zero
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335 avail_out). In the case of a Z_FULL_FLUSH or Z_SYNC_FLUSH, make sure that
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336 avail_out is greater than six to avoid repeated flush markers due to
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337 avail_out == 0 on return.
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338
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339 If the parameter flush is set to Z_FINISH, pending input is processed,
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340 pending output is flushed and deflate returns with Z_STREAM_END if there
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341 was enough output space; if deflate returns with Z_OK, this function must be
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342 called again with Z_FINISH and more output space (updated avail_out) but no
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343 more input data, until it returns with Z_STREAM_END or an error. After
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344 deflate has returned Z_STREAM_END, the only possible operations on the
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345 stream are deflateReset or deflateEnd.
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346
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347 Z_FINISH can be used immediately after deflateInit if all the compression
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348 is to be done in a single step. In this case, avail_out must be at least
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349 the value returned by deflateBound (see below). If deflate does not return
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350 Z_STREAM_END, then it must be called again as described above.
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351
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352 deflate() sets strm->adler to the adler32 checksum of all input read
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353 so far (that is, total_in bytes).
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354
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355 deflate() may update strm->data_type if it can make a good guess about
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356 the input data type (Z_BINARY or Z_TEXT). In doubt, the data is considered
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357 binary. This field is only for information purposes and does not affect
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358 the compression algorithm in any manner.
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359
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360 deflate() returns Z_OK if some progress has been made (more input
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361 processed or more output produced), Z_STREAM_END if all input has been
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362 consumed and all output has been produced (only when flush is set to
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363 Z_FINISH), Z_STREAM_ERROR if the stream state was inconsistent (for example
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364 if next_in or next_out was NULL), Z_BUF_ERROR if no progress is possible
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365 (for example avail_in or avail_out was zero). Note that Z_BUF_ERROR is not
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366 fatal, and deflate() can be called again with more input and more output
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367 space to continue compressing.
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368 */
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369
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370
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371 int deflateEnd(z_streamp strm);
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372 /*
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373 All dynamically allocated data structures for this stream are freed.
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374 This function discards any unprocessed input and does not flush any
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375 pending output.
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376
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377 deflateEnd returns Z_OK if success, Z_STREAM_ERROR if the
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378 stream state was inconsistent, Z_DATA_ERROR if the stream was freed
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379 prematurely (some input or output was discarded). In the error case,
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380 msg may be set but then points to a static string (which must not be
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381 deallocated).
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382 */
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383
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384
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385 /*
|
|
|
386 int inflateInit(z_streamp strm);
|
|
|
387
|
|
|
388 Initializes the internal stream state for decompression. The fields
|
|
|
389 next_in, avail_in, zalloc, zfree and opaque must be initialized before by
|
|
|
390 the caller. If next_in is not Z_NULL and avail_in is large enough (the exact
|
|
|
391 value depends on the compression method), inflateInit determines the
|
|
|
392 compression method from the zlib header and allocates all data structures
|
|
|
393 accordingly; otherwise the allocation will be deferred to the first call of
|
|
|
394 inflate. If zalloc and zfree are set to Z_NULL, inflateInit updates them to
|
|
|
395 use default allocation functions.
|
|
|
396
|
|
|
397 inflateInit returns Z_OK if success, Z_MEM_ERROR if there was not enough
|
|
|
398 memory, Z_VERSION_ERROR if the zlib library version is incompatible with the
|
|
|
399 version assumed by the caller. msg is set to null if there is no error
|
|
|
400 message. inflateInit does not perform any decompression apart from reading
|
|
|
401 the zlib header if present: this will be done by inflate(). (So next_in and
|
|
|
402 avail_in may be modified, but next_out and avail_out are unchanged.)
|
|
|
403 */
|
|
|
404
|
|
|
405
|
|
|
406 int inflate(z_streamp strm, int flush);
|
|
|
407 /*
|
|
|
408 inflate decompresses as much data as possible, and stops when the input
|
|
|
409 buffer becomes empty or the output buffer becomes full. It may introduce
|
|
|
410 some output latency (reading input without producing any output) except when
|
|
|
411 forced to flush.
|
|
|
412
|
|
|
413 The detailed semantics are as follows. inflate performs one or both of the
|
|
|
414 following actions:
|
|
|
415
|
|
|
416 - Decompress more input starting at next_in and update next_in and avail_in
|
|
|
417 accordingly. If not all input can be processed (because there is not
|
|
|
418 enough room in the output buffer), next_in is updated and processing
|
|
|
419 will resume at this point for the next call of inflate().
|
|
|
420
|
|
|
421 - Provide more output starting at next_out and update next_out and avail_out
|
|
|
422 accordingly. inflate() provides as much output as possible, until there
|
|
|
423 is no more input data or no more space in the output buffer (see below
|
|
|
424 about the flush parameter).
|
|
|
425
|
|
|
426 Before the call of inflate(), the application should ensure that at least
|
|
|
427 one of the actions is possible, by providing more input and/or consuming
|
|
|
428 more output, and updating the next_* and avail_* values accordingly.
|
|
|
429 The application can consume the uncompressed output when it wants, for
|
|
|
430 example when the output buffer is full (avail_out == 0), or after each
|
|
|
431 call of inflate(). If inflate returns Z_OK and with zero avail_out, it
|
|
|
432 must be called again after making room in the output buffer because there
|
|
|
433 might be more output pending.
|
|
|
434
|
|
|
435 The flush parameter of inflate() can be Z_NO_FLUSH, Z_SYNC_FLUSH,
|
|
|
436 Z_FINISH, or Z_BLOCK. Z_SYNC_FLUSH requests that inflate() flush as much
|
|
|
437 output as possible to the output buffer. Z_BLOCK requests that inflate() stop
|
|
|
438 if and when it gets to the next deflate block boundary. When decoding the
|
|
|
439 zlib or gzip format, this will cause inflate() to return immediately after
|
|
|
440 the header and before the first block. When doing a raw inflate, inflate()
|
|
|
441 will go ahead and process the first block, and will return when it gets to
|
|
|
442 the end of that block, or when it runs out of data.
|
|
|
443
|
|
|
444 The Z_BLOCK option assists in appending to or combining deflate streams.
|
|
|
445 Also to assist in this, on return inflate() will set strm->data_type to the
|
|
|
446 number of unused bits in the last byte taken from strm->next_in, plus 64
|
|
|
447 if inflate() is currently decoding the last block in the deflate stream,
|
|
|
448 plus 128 if inflate() returned immediately after decoding an end-of-block
|
|
|
449 code or decoding the complete header up to just before the first byte of the
|
|
|
450 deflate stream. The end-of-block will not be indicated until all of the
|
|
|
451 uncompressed data from that block has been written to strm->next_out. The
|
|
|
452 number of unused bits may in general be greater than seven, except when
|
|
|
453 bit 7 of data_type is set, in which case the number of unused bits will be
|
|
|
454 less than eight.
|
|
|
455
|
|
|
456 inflate() should normally be called until it returns Z_STREAM_END or an
|
|
|
457 error. However if all decompression is to be performed in a single step
|
|
|
458 (a single call of inflate), the parameter flush should be set to
|
|
|
459 Z_FINISH. In this case all pending input is processed and all pending
|
|
|
460 output is flushed; avail_out must be large enough to hold all the
|
|
|
461 uncompressed data. (The size of the uncompressed data may have been saved
|
|
|
462 by the compressor for this purpose.) The next operation on this stream must
|
|
|
463 be inflateEnd to deallocate the decompression state. The use of Z_FINISH
|
|
|
464 is never required, but can be used to inform inflate that a faster approach
|
|
|
465 may be used for the single inflate() call.
|
|
|
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 only effect of the flush parameter in this implementation
|
|
|
470 is on the return value of inflate(), as noted below, or when it returns early
|
|
|
471 because Z_BLOCK is used.
|
|
|
472
|
|
|
473 If a preset dictionary is needed after this call (see inflateSetDictionary
|
|
|
474 below), inflate sets strm->adler to the adler32 checksum of the dictionary
|
|
|
475 chosen by the compressor and returns Z_NEED_DICT; otherwise it sets
|
|
|
476 strm->adler to the adler32 checksum of all output produced so far (that is,
|
|
|
477 total_out bytes) and returns Z_OK, Z_STREAM_END or an error code as described
|
|
|
478 below. At the end of the stream, inflate() checks that its computed adler32
|
|
|
479 checksum is equal to that saved by the compressor and returns Z_STREAM_END
|
|
|
480 only if the checksum is correct.
|
|
|
481
|
|
|
482 inflate() will decompress and check either zlib-wrapped or gzip-wrapped
|
|
|
483 deflate data. The header type is detected automatically. Any information
|
|
|
484 contained in the gzip header is not retained, so applications that need that
|
|
|
485 information should instead use raw inflate, see inflateInit2() below, or
|
|
|
486 inflateBack() and perform their own processing of the gzip header and
|
|
|
487 trailer.
|
|
|
488
|
|
|
489 inflate() returns Z_OK if some progress has been made (more input processed
|
|
|
490 or more output produced), Z_STREAM_END if the end of the compressed data has
|
|
|
491 been reached and all uncompressed output has been produced, Z_NEED_DICT if a
|
|
|
492 preset dictionary is needed at this point, Z_DATA_ERROR if the input data was
|
|
|
493 corrupted (input stream not conforming to the zlib format or incorrect check
|
|
|
494 value), Z_STREAM_ERROR if the stream structure was inconsistent (for example
|
|
|
495 if next_in or next_out was NULL), Z_MEM_ERROR if there was not enough memory,
|
|
|
496 Z_BUF_ERROR if no progress is possible or if there was not enough room in the
|
|
|
497 output buffer when Z_FINISH is used. Note that Z_BUF_ERROR is not fatal, and
|
|
|
498 inflate() can be called again with more input and more output space to
|
|
|
499 continue decompressing. If Z_DATA_ERROR is returned, the application may then
|
|
|
500 call inflateSync() to look for a good compression block if a partial recovery
|
|
|
501 of the data is desired.
|
|
|
502 */
|
|
|
503
|
|
|
504
|
|
|
505 int inflateEnd(z_streamp strm);
|
|
|
506 /*
|
|
|
507 All dynamically allocated data structures for this stream are freed.
|
|
|
508 This function discards any unprocessed input and does not flush any
|
|
|
509 pending output.
|
|
|
510
|
|
|
511 inflateEnd returns Z_OK if success, Z_STREAM_ERROR if the stream state
|
|
|
512 was inconsistent. In the error case, msg may be set but then points to a
|
|
|
513 static string (which must not be deallocated).
|
|
|
514 */
|
|
|
515
|
|
|
516 /* Advanced functions */
|
|
|
517
|
|
|
518 /*
|
|
|
519 The following functions are needed only in some special applications.
|
|
|
520 */
|
|
|
521
|
|
|
522 /*
|
|
|
523 int deflateInit2 (z_streamp strm,
|
|
|
524 int level,
|
|
|
525 int method,
|
|
|
526 int windowBits,
|
|
|
527 int memLevel,
|
|
|
528 int strategy);
|
|
|
529
|
|
|
530 This is another version of deflateInit with more compression options. The
|
|
|
531 fields next_in, zalloc, zfree and opaque must be initialized before by
|
|
|
532 the caller.
|
|
|
533
|
|
|
534 The method parameter is the compression method. It must be Z_DEFLATED in
|
|
|
535 this version of the library.
|
|
|
536
|
|
|
537 The windowBits parameter is the base two logarithm of the window size
|
|
|
538 (the size of the history buffer). It should be in the range 8..15 for this
|
|
|
539 version of the library. Larger values of this parameter result in better
|
|
|
540 compression at the expense of memory usage. The default value is 15 if
|
|
|
541 deflateInit is used instead.
|
|
|
542
|
|
|
543 windowBits can also be -8..-15 for raw deflate. In this case, -windowBits
|
|
|
544 determines the window size. deflate() will then generate raw deflate data
|
|
|
545 with no zlib header or trailer, and will not compute an adler32 check value.
|
|
|
546
|
|
|
547 windowBits can also be greater than 15 for optional gzip encoding. Add
|
|
|
548 16 to windowBits to write a simple gzip header and trailer around the
|
|
|
549 compressed data instead of a zlib wrapper. The gzip header will have no
|
|
|
550 file name, no extra data, no comment, no modification time (set to zero),
|
|
|
551 no header crc, and the operating system will be set to 255 (unknown). If a
|
|
|
552 gzip stream is being written, strm->adler is a crc32 instead of an adler32.
|
|
|
553
|
|
|
554 The memLevel parameter specifies how much memory should be allocated
|
|
|
555 for the internal compression state. memLevel=1 uses minimum memory but
|
|
|
556 is slow and reduces compression ratio; memLevel=9 uses maximum memory
|
|
|
557 for optimal speed. The default value is 8. See zconf.h for total memory
|
|
|
558 usage as a function of windowBits and memLevel.
|
|
|
559
|
|
|
560 The strategy parameter is used to tune the compression algorithm. Use the
|
|
|
561 value Z_DEFAULT_STRATEGY for normal data, Z_FILTERED for data produced by a
|
|
|
562 filter (or predictor), Z_HUFFMAN_ONLY to force Huffman encoding only (no
|
|
|
563 string match), or Z_RLE to limit match distances to one (run-length
|
|
|
564 encoding). Filtered data consists mostly of small values with a somewhat
|
|
|
565 random distribution. In this case, the compression algorithm is tuned to
|
|
|
566 compress them better. The effect of Z_FILTERED is to force more Huffman
|
|
|
567 coding and less string matching; it is somewhat intermediate between
|
|
|
568 Z_DEFAULT and Z_HUFFMAN_ONLY. Z_RLE is designed to be almost as fast as
|
|
|
569 Z_HUFFMAN_ONLY, but give better compression for PNG image data. The strategy
|
|
|
570 parameter only affects the compression ratio but not the correctness of the
|
|
|
571 compressed output even if it is not set appropriately. Z_FIXED prevents the
|
|
|
572 use of dynamic Huffman codes, allowing for a simpler decoder for special
|
|
|
573 applications.
|
|
|
574
|
|
|
575 deflateInit2 returns Z_OK if success, Z_MEM_ERROR if there was not enough
|
|
|
576 memory, Z_STREAM_ERROR if a parameter is invalid (such as an invalid
|
|
|
577 method). msg is set to null if there is no error message. deflateInit2 does
|
|
|
578 not perform any compression: this will be done by deflate().
|
|
|
579 */
|
|
|
580
|
|
|
581 int deflateSetDictionary(z_streamp strm,
|
|
|
582 Bytef* dictionary,
|
|
|
583 uInt dictLength);
|
|
|
584 /*
|
|
|
585 Initializes the compression dictionary from the given byte sequence
|
|
|
586 without producing any compressed output. This function must be called
|
|
|
587 immediately after deflateInit, deflateInit2 or deflateReset, before any
|
|
|
588 call of deflate. The compressor and decompressor must use exactly the same
|
|
|
589 dictionary (see inflateSetDictionary).
|
|
|
590
|
|
|
591 The dictionary should consist of strings (byte sequences) that are likely
|
|
|
592 to be encountered later in the data to be compressed, with the most commonly
|
|
|
593 used strings preferably put towards the end of the dictionary. Using a
|
|
|
594 dictionary is most useful when the data to be compressed is short and can be
|
|
|
595 predicted with good accuracy; the data can then be compressed better than
|
|
|
596 with the default empty dictionary.
|
|
|
597
|
|
|
598 Depending on the size of the compression data structures selected by
|
|
|
599 deflateInit or deflateInit2, a part of the dictionary may in effect be
|
|
|
600 discarded, for example if the dictionary is larger than the window size in
|
|
|
601 deflate or deflate2. Thus the strings most likely to be useful should be
|
|
|
602 put at the end of the dictionary, not at the front. In addition, the
|
|
|
603 current implementation of deflate will use at most the window size minus
|
|
|
604 262 bytes of the provided dictionary.
|
|
|
605
|
|
|
606 Upon return of this function, strm->adler is set to the adler32 value
|
|
|
607 of the dictionary; the decompressor may later use this value to determine
|
|
|
608 which dictionary has been used by the compressor. (The adler32 value
|
|
|
609 applies to the whole dictionary even if only a subset of the dictionary is
|
|
|
610 actually used by the compressor.) If a raw deflate was requested, then the
|
|
|
611 adler32 value is not computed and strm->adler is not set.
|
|
|
612
|
|
|
613 deflateSetDictionary returns Z_OK if success, or Z_STREAM_ERROR if a
|
|
|
614 parameter is invalid (such as NULL dictionary) or the stream state is
|
|
|
615 inconsistent (for example if deflate has already been called for this stream
|
|
|
616 or if the compression method is bsort). deflateSetDictionary does not
|
|
|
617 perform any compression: this will be done by deflate().
|
|
|
618 */
|
|
|
619
|
|
|
620 int deflateCopy(z_streamp dest,
|
|
|
621 z_streamp source);
|
|
|
622 /*
|
|
|
623 Sets the destination stream as a complete copy of the source stream.
|
|
|
624
|
|
|
625 This function can be useful when several compression strategies will be
|
|
|
626 tried, for example when there are several ways of pre-processing the input
|
|
|
627 data with a filter. The streams that will be discarded should then be freed
|
|
|
628 by calling deflateEnd. Note that deflateCopy duplicates the internal
|
|
|
629 compression state which can be quite large, so this strategy is slow and
|
|
|
630 can consume lots of memory.
|
|
|
631
|
|
|
632 deflateCopy returns Z_OK if success, Z_MEM_ERROR if there was not
|
|
|
633 enough memory, Z_STREAM_ERROR if the source stream state was inconsistent
|
|
|
634 (such as zalloc being NULL). msg is left unchanged in both source and
|
|
|
635 destination.
|
|
|
636 */
|
|
|
637
|
|
|
638 int deflateReset(z_streamp strm);
|
|
|
639 /*
|
|
|
640 This function is equivalent to deflateEnd followed by deflateInit,
|
|
|
641 but does not free and reallocate all the internal compression state.
|
|
|
642 The stream will keep the same compression level and any other attributes
|
|
|
643 that may have been set by deflateInit2.
|
|
|
644
|
|
|
645 deflateReset returns Z_OK if success, or Z_STREAM_ERROR if the source
|
|
|
646 stream state was inconsistent (such as zalloc or state being NULL).
|
|
|
647 */
|
|
|
648
|
|
|
649 int deflateParams(z_streamp strm,
|
|
|
650 int level,
|
|
|
651 int strategy);
|
|
|
652 /*
|
|
|
653 Dynamically update the compression level and compression strategy. The
|
|
|
654 interpretation of level and strategy is as in deflateInit2. This can be
|
|
|
655 used to switch between compression and straight copy of the input data, or
|
|
|
656 to switch to a different kind of input data requiring a different
|
|
|
657 strategy. If the compression level is changed, the input available so far
|
|
|
658 is compressed with the old level (and may be flushed); the new level will
|
|
|
659 take effect only at the next call of deflate().
|
|
|
660
|
|
|
661 Before the call of deflateParams, the stream state must be set as for
|
|
|
662 a call of deflate(), since the currently available input may have to
|
|
|
663 be compressed and flushed. In particular, strm->avail_out must be non-zero.
|
|
|
664
|
|
|
665 deflateParams returns Z_OK if success, Z_STREAM_ERROR if the source
|
|
|
666 stream state was inconsistent or if a parameter was invalid, Z_BUF_ERROR
|
|
|
667 if strm->avail_out was zero.
|
|
|
668 */
|
|
|
669
|
|
|
670 int deflateTune(z_streamp strm,
|
|
|
671 int good_length,
|
|
|
672 int max_lazy,
|
|
|
673 int nice_length,
|
|
|
674 int max_chain);
|
|
|
675 /*
|
|
|
676 Fine tune deflate's internal compression parameters. This should only be
|
|
|
677 used by someone who understands the algorithm used by zlib's deflate for
|
|
|
678 searching for the best matching string, and even then only by the most
|
|
|
679 fanatic optimizer trying to squeeze out the last compressed bit for their
|
|
|
680 specific input data. Read the deflate.c source code for the meaning of the
|
|
|
681 max_lazy, good_length, nice_length, and max_chain parameters.
|
|
|
682
|
|
|
683 deflateTune() can be called after deflateInit() or deflateInit2(), and
|
|
|
684 returns Z_OK on success, or Z_STREAM_ERROR for an invalid deflate stream.
|
|
|
685 */
|
|
|
686
|
|
|
687 uLong deflateBound(z_streamp strm,
|
|
|
688 uLong sourceLen);
|
|
|
689 /*
|
|
|
690 deflateBound() returns an upper bound on the compressed size after
|
|
|
691 deflation of sourceLen bytes. It must be called after deflateInit()
|
|
|
692 or deflateInit2(). This would be used to allocate an output buffer
|
|
|
693 for deflation in a single pass, and so would be called before deflate().
|
|
|
694 */
|
|
|
695
|
|
|
696 int deflatePrime(z_streamp strm,
|
|
|
697 int bits,
|
|
|
698 int value);
|
|
|
699 /*
|
|
|
700 deflatePrime() inserts bits in the deflate output stream. The intent
|
|
|
701 is that this function is used to start off the deflate output with the
|
|
|
702 bits leftover from a previous deflate stream when appending to it. As such,
|
|
|
703 this function can only be used for raw deflate, and must be used before the
|
|
|
704 first deflate() call after a deflateInit2() or deflateReset(). bits must be
|
|
|
705 less than or equal to 16, and that many of the least significant bits of
|
|
|
706 value will be inserted in the output.
|
|
|
707
|
|
|
708 deflatePrime returns Z_OK if success, or Z_STREAM_ERROR if the source
|
|
|
709 stream state was inconsistent.
|
|
|
710 */
|
|
|
711
|
|
|
712 int deflateSetHeader(z_streamp strm,
|
|
|
713 gz_headerp head);
|
|
|
714 /*
|
|
|
715 deflateSetHeader() provides gzip header information for when a gzip
|
|
|
716 stream is requested by deflateInit2(). deflateSetHeader() may be called
|
|
|
717 after deflateInit2() or deflateReset() and before the first call of
|
|
|
718 deflate(). The text, time, os, extra field, name, and comment information
|
|
|
719 in the provided gz_header structure are written to the gzip header (xflag is
|
|
|
720 ignored -- the extra flags are set according to the compression level). The
|
|
|
721 caller must assure that, if not Z_NULL, name and comment are terminated with
|
|
|
722 a zero byte, and that if extra is not Z_NULL, that extra_len bytes are
|
|
|
723 available there. If hcrc is true, a gzip header crc is included. Note that
|
|
|
724 the current versions of the command-line version of gzip (up through version
|
|
|
725 1.3.x) do not support header crc's, and will report that it is a "multi-part
|
|
|
726 gzip file" and give up.
|
|
|
727
|
|
|
728 If deflateSetHeader is not used, the default gzip header has text false,
|
|
|
729 the time set to zero, and os set to 255, with no extra, name, or comment
|
|
|
730 fields. The gzip header is returned to the default state by deflateReset().
|
|
|
731
|
|
|
732 deflateSetHeader returns Z_OK if success, or Z_STREAM_ERROR if the source
|
|
|
733 stream state was inconsistent.
|
|
|
734 */
|
|
|
735
|
|
|
736 /*
|
|
|
737 int inflateInit2(z_streamp strm,
|
|
|
738 int windowBits);
|
|
|
739
|
|
|
740 This is another version of inflateInit with an extra parameter. The
|
|
|
741 fields next_in, avail_in, zalloc, zfree and opaque must be initialized
|
|
|
742 before by the caller.
|
|
|
743
|
|
|
744 The windowBits parameter is the base two logarithm of the maximum window
|
|
|
745 size (the size of the history buffer). It should be in the range 8..15 for
|
|
|
746 this version of the library. The default value is 15 if inflateInit is used
|
|
|
747 instead. windowBits must be greater than or equal to the windowBits value
|
|
|
748 provided to deflateInit2() while compressing, or it must be equal to 15 if
|
|
|
749 deflateInit2() was not used. If a compressed stream with a larger window
|
|
|
750 size is given as input, inflate() will return with the error code
|
|
|
751 Z_DATA_ERROR instead of trying to allocate a larger window.
|
|
|
752
|
|
|
753 windowBits can also be -8..-15 for raw inflate. In this case, -windowBits
|
|
|
754 determines the window size. inflate() will then process raw deflate data,
|
|
|
755 not looking for a zlib or gzip header, not generating a check value, and not
|
|
|
756 looking for any check values for comparison at the end of the stream. This
|
|
|
757 is for use with other formats that use the deflate compressed data format
|
|
|
758 such as zip. Those formats provide their own check values. If a custom
|
|
|
759 format is developed using the raw deflate format for compressed data, it is
|
|
|
760 recommended that a check value such as an adler32 or a crc32 be applied to
|
|
|
761 the uncompressed data as is done in the zlib, gzip, and zip formats. For
|
|
|
762 most applications, the zlib format should be used as is. Note that comments
|
|
|
763 above on the use in deflateInit2() applies to the magnitude of windowBits.
|
|
|
764
|
|
|
765 windowBits can also be greater than 15 for optional gzip decoding. Add
|
|
|
766 32 to windowBits to enable zlib and gzip decoding with automatic header
|
|
|
767 detection, or add 16 to decode only the gzip format (the zlib format will
|
|
|
768 return a Z_DATA_ERROR). If a gzip stream is being decoded, strm->adler is
|
|
|
769 a crc32 instead of an adler32.
|
|
|
770
|
|
|
771 inflateInit2 returns Z_OK if success, Z_MEM_ERROR if there was not enough
|
|
|
772 memory, Z_STREAM_ERROR if a parameter is invalid (such as a null strm). msg
|
|
|
773 is set to null if there is no error message. inflateInit2 does not perform
|
|
|
774 any decompression apart from reading the zlib header if present: this will
|
|
|
775 be done by inflate(). (So next_in and avail_in may be modified, but next_out
|
|
|
776 and avail_out are unchanged.)
|
|
|
777 */
|
|
|
778
|
|
|
779 int inflateSetDictionary(z_streamp strm,
|
|
|
780 Bytef* dictionary,
|
|
|
781 uInt dictLength);
|
|
|
782 /*
|
|
|
783 Initializes the decompression dictionary from the given uncompressed byte
|
|
|
784 sequence. This function must be called immediately after a call of inflate,
|
|
|
785 if that call returned Z_NEED_DICT. The dictionary chosen by the compressor
|
|
|
786 can be determined from the adler32 value returned by that call of inflate.
|
|
|
787 The compressor and decompressor must use exactly the same dictionary (see
|
|
|
788 deflateSetDictionary). For raw inflate, this function can be called
|
|
|
789 immediately after inflateInit2() or inflateReset() and before any call of
|
|
|
790 inflate() to set the dictionary. The application must insure that the
|
|
|
791 dictionary that was used for compression is provided.
|
|
|
792
|
|
|
793 inflateSetDictionary returns Z_OK if success, Z_STREAM_ERROR if a
|
|
|
794 parameter is invalid (such as NULL dictionary) or the stream state is
|
|
|
795 inconsistent, Z_DATA_ERROR if the given dictionary doesn't match the
|
|
|
796 expected one (incorrect adler32 value). inflateSetDictionary does not
|
|
|
797 perform any decompression: this will be done by subsequent calls of
|
|
|
798 inflate().
|
|
|
799 */
|
|
|
800
|
|
|
801 int inflateSync(z_streamp strm);
|
|
|
802 /*
|
|
|
803 Skips invalid compressed data until a full flush point (see above the
|
|
|
804 description of deflate with Z_FULL_FLUSH) can be found, or until all
|
|
|
805 available input is skipped. No output is provided.
|
|
|
806
|
|
|
807 inflateSync returns Z_OK if a full flush point has been found, Z_BUF_ERROR
|
|
|
808 if no more input was provided, Z_DATA_ERROR if no flush point has been found,
|
|
|
809 or Z_STREAM_ERROR if the stream structure was inconsistent. In the success
|
|
|
810 case, the application may save the current current value of total_in which
|
|
|
811 indicates where valid compressed data was found. In the error case, the
|
|
|
812 application may repeatedly call inflateSync, providing more input each time,
|
|
|
813 until success or end of the input data.
|
|
|
814 */
|
|
|
815
|
|
|
816 int inflateCopy(z_streamp dest,
|
|
|
817 z_streamp source);
|
|
|
818 /*
|
|
|
819 Sets the destination stream as a complete copy of the source stream.
|
|
|
820
|
|
|
821 This function can be useful when randomly accessing a large stream. The
|
|
|
822 first pass through the stream can periodically record the inflate state,
|
|
|
823 allowing restarting inflate at those points when randomly accessing the
|
|
|
824 stream.
|
|
|
825
|
|
|
826 inflateCopy returns Z_OK if success, Z_MEM_ERROR if there was not
|
|
|
827 enough memory, Z_STREAM_ERROR if the source stream state was inconsistent
|
|
|
828 (such as zalloc being NULL). msg is left unchanged in both source and
|
|
|
829 destination.
|
|
|
830 */
|
|
|
831
|
|
|
832 int inflateReset(z_streamp strm);
|
|
|
833 /*
|
|
|
834 This function is equivalent to inflateEnd followed by inflateInit,
|
|
|
835 but does not free and reallocate all the internal decompression state.
|
|
|
836 The stream will keep attributes that may have been set by inflateInit2.
|
|
|
837
|
|
|
838 inflateReset returns Z_OK if success, or Z_STREAM_ERROR if the source
|
|
|
839 stream state was inconsistent (such as zalloc or state being NULL).
|
|
|
840 */
|
|
|
841
|
|
|
842 int inflatePrime(z_streamp strm,
|
|
|
843 int bits,
|
|
|
844 int value);
|
|
|
845 /*
|
|
|
846 This function inserts bits in the inflate input stream. The intent is
|
|
|
847 that this function is used to start inflating at a bit position in the
|
|
|
848 middle of a byte. The provided bits will be used before any bytes are used
|
|
|
849 from next_in. This function should only be used with raw inflate, and
|
|
|
850 should be used before the first inflate() call after inflateInit2() or
|
|
|
851 inflateReset(). bits must be less than or equal to 16, and that many of the
|
|
|
852 least significant bits of value will be inserted in the input.
|
|
|
853
|
|
|
854 inflatePrime returns Z_OK if success, or Z_STREAM_ERROR if the source
|
|
|
855 stream state was inconsistent.
|
|
|
856 */
|
|
|
857
|
|
|
858 int inflateGetHeader(z_streamp strm,
|
|
|
859 gz_headerp head);
|
|
|
860 /*
|
|
|
861 inflateGetHeader() requests that gzip header information be stored in the
|
|
|
862 provided gz_header structure. inflateGetHeader() may be called after
|
|
|
863 inflateInit2() or inflateReset(), and before the first call of inflate().
|
|
|
864 As inflate() processes the gzip stream, head->done is zero until the header
|
|
|
865 is completed, at which time head->done is set to one. If a zlib stream is
|
|
|
866 being decoded, then head->done is set to -1 to indicate that there will be
|
|
|
867 no gzip header information forthcoming. Note that Z_BLOCK can be used to
|
|
|
868 force inflate() to return immediately after header processing is complete
|
|
|
869 and before any actual data is decompressed.
|
|
|
870
|
|
|
871 The text, time, xflags, and os fields are filled in with the gzip header
|
|
|
872 contents. hcrc is set to true if there is a header CRC. (The header CRC
|
|
|
873 was valid if done is set to one.) If extra is not Z_NULL, then extra_max
|
|
|
874 contains the maximum number of bytes to write to extra. Once done is true,
|
|
|
875 extra_len contains the actual extra field length, and extra contains the
|
|
|
876 extra field, or that field truncated if extra_max is less than extra_len.
|
|
|
877 If name is not Z_NULL, then up to name_max characters are written there,
|
|
|
878 terminated with a zero unless the length is greater than name_max. If
|
|
|
879 comment is not Z_NULL, then up to comm_max characters are written there,
|
|
|
880 terminated with a zero unless the length is greater than comm_max. When
|
|
|
881 any of extra, name, or comment are not Z_NULL and the respective field is
|
|
|
882 not present in the header, then that field is set to Z_NULL to signal its
|
|
|
883 absence. This allows the use of deflateSetHeader() with the returned
|
|
|
884 structure to duplicate the header. However if those fields are set to
|
|
|
885 allocated memory, then the application will need to save those pointers
|
|
|
886 elsewhere so that they can be eventually freed.
|
|
|
887
|
|
|
888 If inflateGetHeader is not used, then the header information is simply
|
|
|
889 discarded. The header is always checked for validity, including the header
|
|
|
890 CRC if present. inflateReset() will reset the process to discard the header
|
|
|
891 information. The application would need to call inflateGetHeader() again to
|
|
|
892 retrieve the header from the next gzip stream.
|
|
|
893
|
|
|
894 inflateGetHeader returns Z_OK if success, or Z_STREAM_ERROR if the source
|
|
|
895 stream state was inconsistent.
|
|
|
896 */
|
|
|
897
|
|
|
898 /*
|
|
|
899 int inflateBackInit(z_streamp strm,
|
|
|
900 int windowBits,
|
|
|
901 ubyte* window);
|
|
|
902
|
|
|
903 Initialize the internal stream state for decompression using inflateBack()
|
|
|
904 calls. The fields zalloc, zfree and opaque in strm must be initialized
|
|
|
905 before the call. If zalloc and zfree are Z_NULL, then the default library-
|
|
|
906 derived memory allocation routines are used. windowBits is the base two
|
|
|
907 logarithm of the window size, in the range 8..15. window is a caller
|
|
|
908 supplied buffer of that size. Except for special applications where it is
|
|
|
909 assured that deflate was used with small window sizes, windowBits must be 15
|
|
|
910 and a 32K byte window must be supplied to be able to decompress general
|
|
|
911 deflate streams.
|
|
|
912
|
|
|
913 See inflateBack() for the usage of these routines.
|
|
|
914
|
|
|
915 inflateBackInit will return Z_OK on success, Z_STREAM_ERROR if any of
|
|
|
916 the paramaters are invalid, Z_MEM_ERROR if the internal state could not
|
|
|
917 be allocated, or Z_VERSION_ERROR if the version of the library does not
|
|
|
918 match the version of the header file.
|
|
|
919 */
|
|
|
920
|
|
|
921 alias uint function(void*, ubyte**) in_func;
|
|
|
922 alias int function(void*, ubyte*, uint) out_func;
|
|
|
923
|
|
|
924 int inflateBack(z_streamp strm,
|
|
|
925 in_func in_fn,
|
|
|
926 void* in_desc,
|
|
|
927 out_func out_fn,
|
|
|
928 void* out_desc);
|
|
|
929 /*
|
|
|
930 inflateBack() does a raw inflate with a single call using a call-back
|
|
|
931 interface for input and output. This is more efficient than inflate() for
|
|
|
932 file i/o applications in that it avoids copying between the output and the
|
|
|
933 sliding window by simply making the window itself the output buffer. This
|
|
|
934 function trusts the application to not change the output buffer passed by
|
|
|
935 the output function, at least until inflateBack() returns.
|
|
|
936
|
|
|
937 inflateBackInit() must be called first to allocate the internal state
|
|
|
938 and to initialize the state with the user-provided window buffer.
|
|
|
939 inflateBack() may then be used multiple times to inflate a complete, raw
|
|
|
940 deflate stream with each call. inflateBackEnd() is then called to free
|
|
|
941 the allocated state.
|
|
|
942
|
|
|
943 A raw deflate stream is one with no zlib or gzip header or trailer.
|
|
|
944 This routine would normally be used in a utility that reads zip or gzip
|
|
|
945 files and writes out uncompressed files. The utility would decode the
|
|
|
946 header and process the trailer on its own, hence this routine expects
|
|
|
947 only the raw deflate stream to decompress. This is different from the
|
|
|
948 normal behavior of inflate(), which expects either a zlib or gzip header and
|
|
|
949 trailer around the deflate stream.
|
|
|
950
|
|
|
951 inflateBack() uses two subroutines supplied by the caller that are then
|
|
|
952 called by inflateBack() for input and output. inflateBack() calls those
|
|
|
953 routines until it reads a complete deflate stream and writes out all of the
|
|
|
954 uncompressed data, or until it encounters an error. The function's
|
|
|
955 parameters and return types are defined above in the in_func and out_func
|
|
|
956 typedefs. inflateBack() will call in(in_desc, &buf) which should return the
|
|
|
957 number of bytes of provided input, and a pointer to that input in buf. If
|
|
|
958 there is no input available, in() must return zero--buf is ignored in that
|
|
|
959 case--and inflateBack() will return a buffer error. inflateBack() will call
|
|
|
960 out(out_desc, buf, len) to write the uncompressed data buf[0..len-1]. out()
|
|
|
961 should return zero on success, or non-zero on failure. If out() returns
|
|
|
962 non-zero, inflateBack() will return with an error. Neither in() nor out()
|
|
|
963 are permitted to change the contents of the window provided to
|
|
|
964 inflateBackInit(), which is also the buffer that out() uses to write from.
|
|
|
965 The length written by out() will be at most the window size. Any non-zero
|
|
|
966 amount of input may be provided by in().
|
|
|
967
|
|
|
968 For convenience, inflateBack() can be provided input on the first call by
|
|
|
969 setting strm->next_in and strm->avail_in. If that input is exhausted, then
|
|
|
970 in() will be called. Therefore strm->next_in must be initialized before
|
|
|
971 calling inflateBack(). If strm->next_in is Z_NULL, then in() will be called
|
|
|
972 immediately for input. If strm->next_in is not Z_NULL, then strm->avail_in
|
|
|
973 must also be initialized, and then if strm->avail_in is not zero, input will
|
|
|
974 initially be taken from strm->next_in[0 .. strm->avail_in - 1].
|
|
|
975
|
|
|
976 The in_desc and out_desc parameters of inflateBack() is passed as the
|
|
|
977 first parameter of in() and out() respectively when they are called. These
|
|
|
978 descriptors can be optionally used to pass any information that the caller-
|
|
|
979 supplied in() and out() functions need to do their job.
|
|
|
980
|
|
|
981 On return, inflateBack() will set strm->next_in and strm->avail_in to
|
|
|
982 pass back any unused input that was provided by the last in() call. The
|
|
|
983 return values of inflateBack() can be Z_STREAM_END on success, Z_BUF_ERROR
|
|
|
984 if in() or out() returned an error, Z_DATA_ERROR if there was a format
|
|
|
985 error in the deflate stream (in which case strm->msg is set to indicate the
|
|
|
986 nature of the error), or Z_STREAM_ERROR if the stream was not properly
|
|
|
987 initialized. In the case of Z_BUF_ERROR, an input or output error can be
|
|
|
988 distinguished using strm->next_in which will be Z_NULL only if in() returned
|
|
|
989 an error. If strm->next is not Z_NULL, then the Z_BUF_ERROR was due to
|
|
|
990 out() returning non-zero. (in() will always be called before out(), so
|
|
|
991 strm->next_in is assured to be defined if out() returns non-zero.) Note
|
|
|
992 that inflateBack() cannot return Z_OK.
|
|
|
993 */
|
|
|
994
|
|
|
995 int inflateBackEnd(z_streamp strm);
|
|
|
996 /*
|
|
|
997 All memory allocated by inflateBackInit() is freed.
|
|
|
998
|
|
|
999 inflateBackEnd() returns Z_OK on success, or Z_STREAM_ERROR if the stream
|
|
|
1000 state was inconsistent.
|
|
|
1001 */
|
|
|
1002
|
|
|
1003 uLong zlibCompileFlags();
|
|
|
1004 /* Return flags indicating compile-time options.
|
|
|
1005
|
|
|
1006 Type sizes, two bits each, 00 = 16 bits, 01 = 32, 10 = 64, 11 = other:
|
|
|
1007 1.0: size of uInt
|
|
|
1008 3.2: size of uLong
|
|
|
1009 5.4: size of voidpf (pointer)
|
|
|
1010 7.6: size of z_off_t
|
|
|
1011
|
|
|
1012 Compiler, assembler, and debug options:
|
|
|
1013 8: DEBUG
|
|
|
1014 9: ASMV or ASMINF -- use ASM code
|
|
|
1015 10: ZLIB_WINAPI -- exported functions use the WINAPI calling convention
|
|
|
1016 11: 0 (reserved)
|
|
|
1017
|
|
|
1018 One-time table building (smaller code, but not thread-safe if true):
|
|
|
1019 12: BUILDFIXED -- build static block decoding tables when needed
|
|
|
1020 13: DYNAMIC_CRC_TABLE -- build CRC calculation tables when needed
|
|
|
1021 14,15: 0 (reserved)
|
|
|
1022
|
|
|
1023 Library content (indicates missing functionality):
|
|
|
1024 16: NO_GZCOMPRESS -- gz* functions cannot compress (to avoid linking
|
|
|
1025 deflate code when not needed)
|
|
|
1026 17: NO_GZIP -- deflate can't write gzip streams, and inflate can't detect
|
|
|
1027 and decode gzip streams (to avoid linking crc code)
|
|
|
1028 18-19: 0 (reserved)
|
|
|
1029
|
|
|
1030 Operation variations (changes in library functionality):
|
|
|
1031 20: PKZIP_BUG_WORKAROUND -- slightly more permissive inflate
|
|
|
1032 21: FASTEST -- deflate algorithm with only one, lowest compression level
|
|
|
1033 22,23: 0 (reserved)
|
|
|
1034
|
|
|
1035 The sprintf variant used by gzprintf (zero is best):
|
|
|
1036 24: 0 = vs*, 1 = s* -- 1 means limited to 20 arguments after the format
|
|
|
1037 25: 0 = *nprintf, 1 = *printf -- 1 means gzprintf() not secure!
|
|
|
1038 26: 0 = returns value, 1 = void -- 1 means inferred string length returned
|
|
|
1039
|
|
|
1040 Remainder:
|
|
|
1041 27-31: 0 (reserved)
|
|
|
1042 */
|
|
|
1043
|
|
|
1044
|
|
|
1045 /* utility functions */
|
|
|
1046
|
|
|
1047 /*
|
|
|
1048 The following utility functions are implemented on top of the
|
|
|
1049 basic stream-oriented functions. To simplify the interface, some
|
|
|
1050 default options are assumed (compression level and memory usage,
|
|
|
1051 standard memory allocation functions). The source code of these
|
|
|
1052 utility functions can easily be modified if you need special options.
|
|
|
1053 */
|
|
|
1054
|
|
|
1055 int compress(Bytef* dest,
|
|
|
1056 uLongf* destLen,
|
|
|
1057 Bytef* source,
|
|
|
1058 uLong sourceLen);
|
|
|
1059 /*
|
|
|
1060 Compresses the source buffer into the destination buffer. sourceLen is
|
|
|
1061 the byte length of the source buffer. Upon entry, destLen is the total
|
|
|
1062 size of the destination buffer, which must be at least the value returned
|
|
|
1063 by compressBound(sourceLen). Upon exit, destLen is the actual size of the
|
|
|
1064 compressed buffer.
|
|
|
1065 This function can be used to compress a whole file at once if the
|
|
|
1066 input file is mmap'ed.
|
|
|
1067 compress returns Z_OK if success, Z_MEM_ERROR if there was not
|
|
|
1068 enough memory, Z_BUF_ERROR if there was not enough room in the output
|
|
|
1069 buffer.
|
|
|
1070 */
|
|
|
1071
|
|
|
1072 int compress2(Bytef* dest,
|
|
|
1073 uLongf* destLen,
|
|
|
1074 Bytef* source,
|
|
|
1075 uLong sourceLen,
|
|
|
1076 int level);
|
|
|
1077 /*
|
|
|
1078 Compresses the source buffer into the destination buffer. The level
|
|
|
1079 parameter has the same meaning as in deflateInit. sourceLen is the byte
|
|
|
1080 length of the source buffer. Upon entry, destLen is the total size of the
|
|
|
1081 destination buffer, which must be at least the value returned by
|
|
|
1082 compressBound(sourceLen). Upon exit, destLen is the actual size of the
|
|
|
1083 compressed buffer.
|
|
|
1084
|
|
|
1085 compress2 returns Z_OK if success, Z_MEM_ERROR if there was not enough
|
|
|
1086 memory, Z_BUF_ERROR if there was not enough room in the output buffer,
|
|
|
1087 Z_STREAM_ERROR if the level parameter is invalid.
|
|
|
1088 */
|
|
|
1089
|
|
|
1090 uLong compressBound(uLong sourceLen);
|
|
|
1091 /*
|
|
|
1092 compressBound() returns an upper bound on the compressed size after
|
|
|
1093 compress() or compress2() on sourceLen bytes. It would be used before
|
|
|
1094 a compress() or compress2() call to allocate the destination buffer.
|
|
|
1095 */
|
|
|
1096
|
|
|
1097 int uncompress(Bytef* dest,
|
|
|
1098 uLongf* destLen,
|
|
|
1099 Bytef* source,
|
|
|
1100 uLong sourceLen);
|
|
|
1101 /*
|
|
|
1102 Decompresses the source buffer into the destination buffer. sourceLen is
|
|
|
1103 the byte length of the source buffer. Upon entry, destLen is the total
|
|
|
1104 size of the destination buffer, which must be large enough to hold the
|
|
|
1105 entire uncompressed data. (The size of the uncompressed data must have
|
|
|
1106 been saved previously by the compressor and transmitted to the decompressor
|
|
|
1107 by some mechanism outside the scope of this compression library.)
|
|
|
1108 Upon exit, destLen is the actual size of the compressed buffer.
|
|
|
1109 This function can be used to decompress a whole file at once if the
|
|
|
1110 input file is mmap'ed.
|
|
|
1111
|
|
|
1112 uncompress returns Z_OK if success, Z_MEM_ERROR if there was not
|
|
|
1113 enough memory, Z_BUF_ERROR if there was not enough room in the output
|
|
|
1114 buffer, or Z_DATA_ERROR if the input data was corrupted or incomplete.
|
|
|
1115 */
|
|
|
1116
|
|
|
1117
|
|
|
1118 typedef voidp gzFile;
|
|
|
1119
|
|
|
1120 gzFile gzopen(char* path, char* mode);
|
|
|
1121 /*
|
|
|
1122 Opens a gzip (.gz) file for reading or writing. The mode parameter
|
|
|
1123 is as in fopen ("rb" or "wb") but can also include a compression level
|
|
|
1124 ("wb9") or a strategy: 'f' for filtered data as in "wb6f", 'h' for
|
|
|
1125 Huffman only compression as in "wb1h", or 'R' for run-length encoding
|
|
|
1126 as in "wb1R". (See the description of deflateInit2 for more information
|
|
|
1127 about the strategy parameter.)
|
|
|
1128
|
|
|
1129 gzopen can be used to read a file which is not in gzip format; in this
|
|
|
1130 case gzread will directly read from the file without decompression.
|
|
|
1131
|
|
|
1132 gzopen returns NULL if the file could not be opened or if there was
|
|
|
1133 insufficient memory to allocate the (de)compression state; errno
|
|
|
1134 can be checked to distinguish the two cases (if errno is zero, the
|
|
|
1135 zlib error is Z_MEM_ERROR). */
|
|
|
1136
|
|
|
1137 gzFile gzdopen(int fd, char* mode);
|
|
|
1138 /*
|
|
|
1139 gzdopen() associates a gzFile with the file descriptor fd. File
|
|
|
1140 descriptors are obtained from calls like open, dup, creat, pipe or
|
|
|
1141 fileno (in the file has been previously opened with fopen).
|
|
|
1142 The mode parameter is as in gzopen.
|
|
|
1143 The next call of gzclose on the returned gzFile will also close the
|
|
|
1144 file descriptor fd, just like fclose(fdopen(fd), mode) closes the file
|
|
|
1145 descriptor fd. If you want to keep fd open, use gzdopen(dup(fd), mode).
|
|
|
1146 gzdopen returns NULL if there was insufficient memory to allocate
|
|
|
1147 the (de)compression state.
|
|
|
1148 */
|
|
|
1149
|
|
|
1150 int gzsetparams(gzFile file, int level, int strategy);
|
|
|
1151 /*
|
|
|
1152 Dynamically update the compression level or strategy. See the description
|
|
|
1153 of deflateInit2 for the meaning of these parameters.
|
|
|
1154 gzsetparams returns Z_OK if success, or Z_STREAM_ERROR if the file was not
|
|
|
1155 opened for writing.
|
|
|
1156 */
|
|
|
1157
|
|
|
1158 int gzread(gzFile file, voidp buf, uint len);
|
|
|
1159 /*
|
|
|
1160 Reads the given number of uncompressed bytes from the compressed file.
|
|
|
1161 If the input file was not in gzip format, gzread copies the given number
|
|
|
1162 of bytes into the buffer.
|
|
|
1163 gzread returns the number of uncompressed bytes actually read (0 for
|
|
|
1164 end of file, -1 for error). */
|
|
|
1165
|
|
|
1166 int gzwrite(gzFile file, voidpc buf, uint len);
|
|
|
1167 /*
|
|
|
1168 Writes the given number of uncompressed bytes into the compressed file.
|
|
|
1169 gzwrite returns the number of uncompressed bytes actually written
|
|
|
1170 (0 in case of error).
|
|
|
1171 */
|
|
|
1172
|
|
|
1173 int gzprintf (gzFile file, char* format, ...);
|
|
|
1174 /*
|
|
|
1175 Converts, formats, and writes the args to the compressed file under
|
|
|
1176 control of the format string, as in fprintf. gzprintf returns the number of
|
|
|
1177 uncompressed bytes actually written (0 in case of error). The number of
|
|
|
1178 uncompressed bytes written is limited to 4095. The caller should assure that
|
|
|
1179 this limit is not exceeded. If it is exceeded, then gzprintf() will return
|
|
|
1180 return an error (0) with nothing written. In this case, there may also be a
|
|
|
1181 buffer overflow with unpredictable consequences, which is possible only if
|
|
|
1182 zlib was compiled with the insecure functions sprintf() or vsprintf()
|
|
|
1183 because the secure snprintf() or vsnprintf() functions were not available.
|
|
|
1184 */
|
|
|
1185
|
|
|
1186 int gzputs(gzFile file, char* s);
|
|
|
1187 /*
|
|
|
1188 Writes the given null-terminated string to the compressed file, excluding
|
|
|
1189 the terminating null character.
|
|
|
1190 gzputs returns the number of characters written, or -1 in case of error.
|
|
|
1191 */
|
|
|
1192
|
|
|
1193 char* gzgets(gzFile file, char* buf, int len);
|
|
|
1194 /*
|
|
|
1195 Reads bytes from the compressed file until len-1 characters are read, or
|
|
|
1196 a newline character is read and transferred to buf, or an end-of-file
|
|
|
1197 condition is encountered. The string is then terminated with a null
|
|
|
1198 character.
|
|
|
1199 gzgets returns buf, or Z_NULL in case of error.
|
|
|
1200 */
|
|
|
1201
|
|
|
1202 int gzputc(gzFile file, int c);
|
|
|
1203 /*
|
|
|
1204 Writes c, converted to an unsigned char, into the compressed file.
|
|
|
1205 gzputc returns the value that was written, or -1 in case of error.
|
|
|
1206 */
|
|
|
1207
|
|
|
1208 int gzgetc (gzFile file);
|
|
|
1209 /*
|
|
|
1210 Reads one byte from the compressed file. gzgetc returns this byte
|
|
|
1211 or -1 in case of end of file or error.
|
|
|
1212 */
|
|
|
1213
|
|
|
1214 int gzungetc(int c, gzFile file);
|
|
|
1215 /*
|
|
|
1216 Push one character back onto the stream to be read again later.
|
|
|
1217 Only one character of push-back is allowed. gzungetc() returns the
|
|
|
1218 character pushed, or -1 on failure. gzungetc() will fail if a
|
|
|
1219 character has been pushed but not read yet, or if c is -1. The pushed
|
|
|
1220 character will be discarded if the stream is repositioned with gzseek()
|
|
|
1221 or gzrewind().
|
|
|
1222 */
|
|
|
1223
|
|
|
1224 int gzflush(gzFile file, int flush);
|
|
|
1225 /*
|
|
|
1226 Flushes all pending output into the compressed file. The parameter
|
|
|
1227 flush is as in the deflate() function. The return value is the zlib
|
|
|
1228 error number (see function gzerror below). gzflush returns Z_OK if
|
|
|
1229 the flush parameter is Z_FINISH and all output could be flushed.
|
|
|
1230 gzflush should be called only when strictly necessary because it can
|
|
|
1231 degrade compression.
|
|
|
1232 */
|
|
|
1233
|
|
|
1234 z_off_t gzseek (gzFile file, z_off_t offset, int whence);
|
|
|
1235 /*
|
|
|
1236 Sets the starting position for the next gzread or gzwrite on the
|
|
|
1237 given compressed file. The offset represents a number of bytes in the
|
|
|
1238 uncompressed data stream. The whence parameter is defined as in lseek(2);
|
|
|
1239 the value SEEK_END is not supported.
|
|
|
1240 If the file is opened for reading, this function is emulated but can be
|
|
|
1241 extremely slow. If the file is opened for writing, only forward seeks are
|
|
|
1242 supported; gzseek then compresses a sequence of zeroes up to the new
|
|
|
1243 starting position.
|
|
|
1244
|
|
|
1245 gzseek returns the resulting offset location as measured in bytes from
|
|
|
1246 the beginning of the uncompressed stream, or -1 in case of error, in
|
|
|
1247 particular if the file is opened for writing and the new starting position
|
|
|
1248 would be before the current position.
|
|
|
1249 */
|
|
|
1250
|
|
|
1251 int gzrewind(gzFile file);
|
|
|
1252 /*
|
|
|
1253 Rewinds the given file. This function is supported only for reading.
|
|
|
1254
|
|
|
1255 gzrewind(file) is equivalent to (int)gzseek(file, 0L, SEEK_SET)
|
|
|
1256 */
|
|
|
1257
|
|
|
1258 z_off_t gztell (gzFile file);
|
|
|
1259 /*
|
|
|
1260 Returns the starting position for the next gzread or gzwrite on the
|
|
|
1261 given compressed file. This position represents a number of bytes in the
|
|
|
1262 uncompressed data stream.
|
|
|
1263
|
|
|
1264 gztell(file) is equivalent to gzseek(file, 0L, SEEK_CUR)
|
|
|
1265 */
|
|
|
1266
|
|
|
1267 int gzeof(gzFile file);
|
|
|
1268 /*
|
|
|
1269 Returns 1 when EOF has previously been detected reading the given
|
|
|
1270 input stream, otherwise zero.
|
|
|
1271 */
|
|
|
1272
|
|
|
1273 int gzdirect(gzFile file);
|
|
|
1274 /*
|
|
|
1275 Returns 1 if file is being read directly without decompression, otherwise
|
|
|
1276 zero.
|
|
|
1277 */
|
|
|
1278
|
|
|
1279 int gzclose(gzFile file);
|
|
|
1280 /*
|
|
|
1281 Flushes all pending output if necessary, closes the compressed file
|
|
|
1282 and deallocates all the (de)compression state. The return value is the zlib
|
|
|
1283 error number (see function gzerror below).
|
|
|
1284 */
|
|
|
1285
|
|
|
1286 char* gzerror(gzFile file, int* errnum);
|
|
|
1287 /*
|
|
|
1288 Returns the error message for the last error which occurred on the
|
|
|
1289 given compressed file. errnum is set to zlib error number. If an
|
|
|
1290 error occurred in the file system and not in the compression library,
|
|
|
1291 errnum is set to Z_ERRNO and the application may consult errno
|
|
|
1292 to get the exact error code.
|
|
|
1293 */
|
|
|
1294
|
|
|
1295 void gzclearerr(gzFile file);
|
|
|
1296 /*
|
|
|
1297 Clears the error and end-of-file flags for file. This is analogous to the
|
|
|
1298 clearerr() function in stdio. This is useful for continuing to read a gzip
|
|
|
1299 file that is being written concurrently.
|
|
|
1300 */
|
|
|
1301
|
|
|
1302 /* checksum functions */
|
|
|
1303
|
|
|
1304 /*
|
|
|
1305 These functions are not related to compression but are exported
|
|
|
1306 anyway because they might be useful in applications using the
|
|
|
1307 compression library.
|
|
|
1308 */
|
|
|
1309
|
|
|
1310 uLong adler32(uLong adler, Bytef* buf, uInt len);
|
|
|
1311 /*
|
|
|
1312 Update a running Adler-32 checksum with the bytes buf[0..len-1] and
|
|
|
1313 return the updated checksum. If buf is NULL, this function returns
|
|
|
1314 the required initial value for the checksum.
|
|
|
1315 An Adler-32 checksum is almost as reliable as a CRC32 but can be computed
|
|
|
1316 much faster. Usage example:
|
|
|
1317
|
|
|
1318 uLong adler = adler32(0L, Z_NULL, 0);
|
|
|
1319
|
|
|
1320 while (read_buffer(buffer, length) != EOF) {
|
|
|
1321 adler = adler32(adler, buffer, length);
|
|
|
1322 }
|
|
|
1323 if (adler != original_adler) error();
|
|
|
1324 */
|
|
|
1325
|
|
|
1326 uLong adler32_combine(uLong adler1, uLong adler2, z_off_t len2);
|
|
|
1327 /*
|
|
|
1328 Combine two Adler-32 checksums into one. For two sequences of bytes, seq1
|
|
|
1329 and seq2 with lengths len1 and len2, Adler-32 checksums were calculated for
|
|
|
1330 each, adler1 and adler2. adler32_combine() returns the Adler-32 checksum of
|
|
|
1331 seq1 and seq2 concatenated, requiring only adler1, adler2, and len2.
|
|
|
1332 */
|
|
|
1333
|
|
|
1334 uLong crc32(uLong crc, Bytef* buf, uInt len);
|
|
|
1335 /*
|
|
|
1336 Update a running CRC-32 with the bytes buf[0..len-1] and return the
|
|
|
1337 updated CRC-32. If buf is NULL, this function returns the required initial
|
|
|
1338 value for the for the crc. Pre- and post-conditioning (one's complement) is
|
|
|
1339 performed within this function so it shouldn't be done by the application.
|
|
|
1340 Usage example:
|
|
|
1341
|
|
|
1342 uLong crc = crc32(0L, Z_NULL, 0);
|
|
|
1343
|
|
|
1344 while (read_buffer(buffer, length) != EOF) {
|
|
|
1345 crc = crc32(crc, buffer, length);
|
|
|
1346 }
|
|
|
1347 if (crc != original_crc) error();
|
|
|
1348 */
|
|
|
1349
|
|
|
1350 uLong crc32_combine(uLong crc1, uLong crc2, z_off_t len2);
|
|
|
1351
|
|
|
1352 /*
|
|
|
1353 Combine two CRC-32 check values into one. For two sequences of bytes,
|
|
|
1354 seq1 and seq2 with lengths len1 and len2, CRC-32 check values were
|
|
|
1355 calculated for each, crc1 and crc2. crc32_combine() returns the CRC-32
|
|
|
1356 check value of seq1 and seq2 concatenated, requiring only crc1, crc2, and
|
|
|
1357 len2.
|
|
|
1358 */
|
|
|
1359
|
|
|
1360
|
|
|
1361 /* various hacks, don't look :) */
|
|
|
1362
|
|
|
1363 /* deflateInit and inflateInit are macros to allow checking the zlib version
|
|
|
1364 * and the compiler's view of z_stream:
|
|
|
1365 */
|
|
|
1366 int deflateInit_(z_streamp strm,
|
|
|
1367 int level,
|
|
|
1368 char* ver,
|
|
|
1369 int stream_size);
|
|
|
1370 int inflateInit_(z_streamp strm,
|
|
|
1371 char* ver,
|
|
|
1372 int stream_size);
|
|
|
1373 int deflateInit2_(z_streamp strm,
|
|
|
1374 int level,
|
|
|
1375 int method,
|
|
|
1376 int windowBits,
|
|
|
1377 int memLevel,
|
|
|
1378 int strategy,
|
|
|
1379 char* ver,
|
|
|
1380 int stream_size);
|
|
|
1381 int inflateInit2_(z_streamp strm,
|
|
|
1382 int windowBits,
|
|
|
1383 char* ver,
|
|
|
1384 int stream_size);
|
|
|
1385 int inflateBackInit_(z_streamp strm,
|
|
|
1386 int windowBits,
|
|
|
1387 ubyte* window,
|
|
|
1388 char* ver,
|
|
|
1389 int stream_size);
|
|
|
1390
|
|
|
1391 extern (D) int deflateInit(z_streamp strm,
|
|
|
1392 int level)
|
|
|
1393 {
|
|
|
1394 return deflateInit_(strm,
|
|
|
1395 level,
|
|
|
1396 ZLIB_VERSION,
|
|
|
1397 z_stream.sizeof);
|
|
|
1398 }
|
|
|
1399
|
|
|
1400 extern (D) int inflateInit(z_streamp strm)
|
|
|
1401 {
|
|
|
1402 return inflateInit_(strm,
|
|
|
1403 ZLIB_VERSION,
|
|
|
1404 z_stream.sizeof);
|
|
|
1405 }
|
|
|
1406
|
|
|
1407 extern (D) int deflateInit2(z_streamp strm,
|
|
|
1408 int level,
|
|
|
1409 int method,
|
|
|
1410 int windowBits,
|
|
|
1411 int memLevel,
|
|
|
1412 int strategy)
|
|
|
1413 {
|
|
|
1414 return deflateInit2_(strm,
|
|
|
1415 level,
|
|
|
1416 method,
|
|
|
1417 windowBits,
|
|
|
1418 memLevel,
|
|
|
1419 strategy,
|
|
|
1420 ZLIB_VERSION,
|
|
|
1421 z_stream.sizeof);
|
|
|
1422 }
|
|
|
1423
|
|
|
1424 extern (D) int inflateInit2(z_streamp strm,
|
|
|
1425 int windowBits)
|
|
|
1426 {
|
|
|
1427 return inflateInit2_(strm,
|
|
|
1428 windowBits,
|
|
|
1429 ZLIB_VERSION,
|
|
|
1430 z_stream.sizeof);
|
|
|
1431 }
|
|
|
1432
|
|
|
1433 extern (D) int inflateBackInit(z_streamp strm,
|
|
|
1434 int windowBits,
|
|
|
1435 ubyte* window)
|
|
|
1436 {
|
|
|
1437 return inflateBackInit_(strm,
|
|
|
1438 windowBits,
|
|
|
1439 window,
|
|
|
1440 ZLIB_VERSION,
|
|
|
1441 z_stream.sizeof);
|
|
|
1442 }
|
|
|
1443
|
|
|
1444 char* zError(int);
|
|
|
1445 int inflateSyncPoint(z_streamp z);
|
|
|
1446 uLongf* get_crc_table();
|
