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145
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1 /* zlib.d: modified from zlib.h by Walter Bright */
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2 /* updated from 1.2.1 to 1.2.3 by Thomas Kuehne */
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3 /* updated from 1.2.3 to 1.2.8 by Dmitry Atamanov */
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4 /* updated from 1.2.8 to 1.2.11 by Iain Buclaw */
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5
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6 module etc.c.zlib;
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7
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8 import core.stdc.config;
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9
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10 /* zlib.h -- interface of the 'zlib' general purpose compression library
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11 version 1.2.11, January 15th, 2017
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12
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13 Copyright (C) 1995-2017 Jean-loup Gailly and Mark Adler
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14
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15 This software is provided 'as-is', without any express or implied
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16 warranty. In no event will the authors be held liable for any damages
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17 arising from the use of this software.
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18
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19 Permission is granted to anyone to use this software for any purpose,
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20 including commercial applications, and to alter it and redistribute it
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21 freely, subject to the following restrictions:
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22
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23 1. The origin of this software must not be misrepresented; you must not
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24 claim that you wrote the original software. If you use this software
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25 in a product, an acknowledgment in the product documentation would be
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26 appreciated but is not required.
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27 2. Altered source versions must be plainly marked as such, and must not be
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28 misrepresented as being the original software.
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29 3. This notice may not be removed or altered from any source distribution.
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30
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31 Jean-loup Gailly Mark Adler
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32 jloup@gzip.org madler@alumni.caltech.edu
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33
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34
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35 The data format used by the zlib library is described by RFCs (Request for
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36 Comments) 1950 to 1952 in the files http://tools.ietf.org/html/rfc1950
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37 (zlib format), rfc1951 (deflate format) and rfc1952 (gzip format).
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38 */
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39
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40 nothrow:
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41 extern (C):
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42
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43 const char[] ZLIB_VERSION = "1.2.11";
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44 const ZLIB_VERNUM = 0x12b0;
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45
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46 /*
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47 The 'zlib' compression library provides in-memory compression and
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48 decompression functions, including integrity checks of the uncompressed data.
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49 This version of the library supports only one compression method (deflation)
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50 but other algorithms will be added later and will have the same stream
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51 interface.
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52
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53 Compression can be done in a single step if the buffers are large enough,
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54 or can be done by repeated calls of the compression function. In the latter
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55 case, the application must provide more input and/or consume the output
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56 (providing more output space) before each call.
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57
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58 The compressed data format used by default by the in-memory functions is
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59 the zlib format, which is a zlib wrapper documented in RFC 1950, wrapped
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60 around a deflate stream, which is itself documented in RFC 1951.
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61
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62 The library also supports reading and writing files in gzip (.gz) format
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63 with an interface similar to that of stdio using the functions that start
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64 with "gz". The gzip format is different from the zlib format. gzip is a
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65 gzip wrapper, documented in RFC 1952, wrapped around a deflate stream.
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66
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67 This library can optionally read and write gzip and raw deflate streams in
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68 memory as well.
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69
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70 The zlib format was designed to be compact and fast for use in memory
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71 and on communications channels. The gzip format was designed for single-
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72 file compression on file systems, has a larger header than zlib to maintain
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73 directory information, and uses a different, slower check method than zlib.
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74
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75 The library does not install any signal handler. The decoder checks
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76 the consistency of the compressed data, so the library should never crash
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77 even in the case of corrupted input.
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78 */
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79
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80 alias alloc_func = void* function (void* opaque, uint items, uint size);
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81 alias free_func = void function (void* opaque, void* address);
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82
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83 struct z_stream
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84 {
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85 const(ubyte)* next_in; /* next input byte */
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86 uint avail_in; /* number of bytes available at next_in */
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87 c_ulong total_in; /* total nb of input bytes read so far */
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88
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89 ubyte* next_out; /* next output byte will go here */
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90 uint avail_out; /* remaining free space at next_out */
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91 c_ulong total_out; /* total nb of bytes output so far */
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92
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93 const(char)* msg; /* last error message, NULL if no error */
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94 void* state; /* not visible by applications */
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95
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96 alloc_func zalloc; /* used to allocate the internal state */
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97 free_func zfree; /* used to free the internal state */
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98 void* opaque; /* private data object passed to zalloc and zfree */
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99
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100 int data_type; /* best guess about the data type: binary or text
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101 for deflate, or the decoding state for inflate */
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102 c_ulong adler; /* Adler-32 or CRC-32 value of the uncompressed data */
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103 c_ulong reserved; /* reserved for future use */
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104 }
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105
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106 alias z_streamp = z_stream*;
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107
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108 /*
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109 gzip header information passed to and from zlib routines. See RFC 1952
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110 for more details on the meanings of these fields.
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111 */
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112 struct gz_header
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113 {
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114 int text; /* true if compressed data believed to be text */
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115 c_ulong time; /* modification time */
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116 int xflags; /* extra flags (not used when writing a gzip file) */
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117 int os; /* operating system */
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118 byte *extra; /* pointer to extra field or Z_NULL if none */
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119 uint extra_len; /* extra field length (valid if extra != Z_NULL) */
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120 uint extra_max; /* space at extra (only when reading header) */
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121 byte* name; /* pointer to zero-terminated file name or Z_NULL */
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122 uint name_max; /* space at name (only when reading header) */
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123 byte* comment; /* pointer to zero-terminated comment or Z_NULL */
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124 uint comm_max; /* space at comment (only when reading header) */
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125 int hcrc; /* true if there was or will be a header crc */
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126 int done; /* true when done reading gzip header (not used
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127 when writing a gzip file) */
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128 }
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129
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130 alias gz_headerp = gz_header*;
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131
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132 /*
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133 The application must update next_in and avail_in when avail_in has dropped
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134 to zero. It must update next_out and avail_out when avail_out has dropped
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135 to zero. The application must initialize zalloc, zfree and opaque before
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136 calling the init function. All other fields are set by the compression
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137 library and must not be updated by the application.
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138
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139 The opaque value provided by the application will be passed as the first
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140 parameter for calls of zalloc and zfree. This can be useful for custom
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141 memory management. The compression library attaches no meaning to the
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142 opaque value.
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143
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144 zalloc must return Z_NULL if there is not enough memory for the object.
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145 If zlib is used in a multi-threaded application, zalloc and zfree must be
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146 thread safe. In that case, zlib is thread-safe. When zalloc and zfree are
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147 Z_NULL on entry to the initialization function, they are set to internal
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148 routines that use the standard library functions malloc() and free().
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149
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150 On 16-bit systems, the functions zalloc and zfree must be able to allocate
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151 exactly 65536 bytes, but will not be required to allocate more than this if
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152 the symbol MAXSEG_64K is defined (see zconf.h). WARNING: On MSDOS, pointers
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153 returned by zalloc for objects of exactly 65536 bytes *must* have their
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154 offset normalized to zero. The default allocation function provided by this
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155 library ensures this (see zutil.c). To reduce memory requirements and avoid
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156 any allocation of 64K objects, at the expense of compression ratio, compile
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157 the library with -DMAX_WBITS=14 (see zconf.h).
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158
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159 The fields total_in and total_out can be used for statistics or progress
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160 reports. After compression, total_in holds the total size of the
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161 uncompressed data and may be saved for use by the decompressor (particularly
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162 if the decompressor wants to decompress everything in a single step).
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163 */
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164
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165 /* constants */
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166
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167 enum
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168 {
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169 Z_NO_FLUSH = 0,
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170 Z_PARTIAL_FLUSH = 1, /* will be removed, use Z_SYNC_FLUSH instead */
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171 Z_SYNC_FLUSH = 2,
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172 Z_FULL_FLUSH = 3,
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173 Z_FINISH = 4,
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174 Z_BLOCK = 5,
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175 Z_TREES = 6,
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176 }
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177 /* Allowed flush values; see deflate() and inflate() below for details */
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178
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179 enum
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180 {
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181 Z_OK = 0,
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182 Z_STREAM_END = 1,
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183 Z_NEED_DICT = 2,
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184 Z_ERRNO = -1,
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185 Z_STREAM_ERROR = -2,
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186 Z_DATA_ERROR = -3,
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187 Z_MEM_ERROR = -4,
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188 Z_BUF_ERROR = -5,
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189 Z_VERSION_ERROR = -6,
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190 }
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191 /* Return codes for the compression/decompression functions. Negative
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192 * values are errors, positive values are used for special but normal events.
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193 */
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194
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195 enum
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196 {
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197 Z_NO_COMPRESSION = 0,
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198 Z_BEST_SPEED = 1,
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199 Z_BEST_COMPRESSION = 9,
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200 Z_DEFAULT_COMPRESSION = -1,
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201 }
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202 /* compression levels */
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203
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204 enum
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205 {
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206 Z_FILTERED = 1,
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207 Z_HUFFMAN_ONLY = 2,
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208 Z_RLE = 3,
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209 Z_FIXED = 4,
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210 Z_DEFAULT_STRATEGY = 0,
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211 }
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212 /* compression strategy; see deflateInit2() below for details */
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213
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214 enum
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215 {
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216 Z_BINARY = 0,
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217 Z_TEXT = 1,
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218 Z_UNKNOWN = 2,
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219
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220 Z_ASCII = Z_TEXT
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221 }
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222 /* Possible values of the data_type field for deflate() */
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223
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224 enum
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225 {
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226 Z_DEFLATED = 8,
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227 }
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228 /* The deflate compression method (the only one supported in this version) */
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229
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230 const int Z_NULL = 0; /* for initializing zalloc, zfree, opaque */
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231
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232 /* basic functions */
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233
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234 const(char)* zlibVersion();
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235 /* The application can compare zlibVersion and ZLIB_VERSION for consistency.
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236 If the first character differs, the library code actually used is not
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237 compatible with the zlib.h header file used by the application. This check
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238 is automatically made by deflateInit and inflateInit.
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239 */
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240
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241 int deflateInit(z_streamp strm, int level)
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242 {
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243 return deflateInit_(strm, level, ZLIB_VERSION.ptr, z_stream.sizeof);
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244 }
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245 /*
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246 Initializes the internal stream state for compression. The fields
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247 zalloc, zfree and opaque must be initialized before by the caller. If
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248 zalloc and zfree are set to Z_NULL, deflateInit updates them to use default
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249 allocation functions.
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250
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251 The compression level must be Z_DEFAULT_COMPRESSION, or between 0 and 9:
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252 1 gives best speed, 9 gives best compression, 0 gives no compression at all
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253 (the input data is simply copied a block at a time). Z_DEFAULT_COMPRESSION
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254 requests a default compromise between speed and compression (currently
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255 equivalent to level 6).
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256
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257 deflateInit returns Z_OK if success, Z_MEM_ERROR if there was not enough
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258 memory, Z_STREAM_ERROR if level is not a valid compression level, or
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259 Z_VERSION_ERROR if the zlib library version (zlib_version) is incompatible
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260 with the version assumed by the caller (ZLIB_VERSION). msg is set to null
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261 if there is no error message. deflateInit does not perform any compression:
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262 this will be done by deflate().
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263 */
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264
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265
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266 int deflate(z_streamp strm, int flush);
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267 /*
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268 deflate compresses as much data as possible, and stops when the input
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269 buffer becomes empty or the output buffer becomes full. It may introduce
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270 some output latency (reading input without producing any output) except when
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271 forced to flush.
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272
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273 The detailed semantics are as follows. deflate performs one or both of the
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274 following actions:
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275
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276 - Compress more input starting at next_in and update next_in and avail_in
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277 accordingly. If not all input can be processed (because there is not
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278 enough room in the output buffer), next_in and avail_in are updated and
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279 processing will resume at this point for the next call of deflate().
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280
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281 - Generate more output starting at next_out and update next_out and avail_out
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282 accordingly. This action is forced if the parameter flush is non zero.
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283 Forcing flush frequently degrades the compression ratio, so this parameter
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284 should be set only when necessary. Some output may be provided even if
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285 flush is zero.
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286
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287 Before the call of deflate(), the application should ensure that at least
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288 one of the actions is possible, by providing more input and/or consuming more
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289 output, and updating avail_in or avail_out accordingly; avail_out should
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290 never be zero before the call. The application can consume the compressed
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291 output when it wants, for example when the output buffer is full (avail_out
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292 == 0), or after each call of deflate(). If deflate returns Z_OK and with
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293 zero avail_out, it must be called again after making room in the output
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294 buffer because there might be more output pending. See deflatePending(),
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295 which can be used if desired to determine whether or not there is more ouput
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296 in that case.
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297
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298 Normally the parameter flush is set to Z_NO_FLUSH, which allows deflate to
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299 decide how much data to accumulate before producing output, in order to
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300 maximize compression.
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301
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302 If the parameter flush is set to Z_SYNC_FLUSH, all pending output is
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303 flushed to the output buffer and the output is aligned on a byte boundary, so
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304 that the decompressor can get all input data available so far. (In
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305 particular avail_in is zero after the call if enough output space has been
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306 provided before the call.) Flushing may degrade compression for some
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307 compression algorithms and so it should be used only when necessary. This
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308 completes the current deflate block and follows it with an empty stored block
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309 that is three bits plus filler bits to the next byte, followed by four bytes
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310 (00 00 ff ff).
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311
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312 If flush is set to Z_PARTIAL_FLUSH, all pending output is flushed to the
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313 output buffer, but the output is not aligned to a byte boundary. All of the
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314 input data so far will be available to the decompressor, as for Z_SYNC_FLUSH.
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315 This completes the current deflate block and follows it with an empty fixed
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316 codes block that is 10 bits long. This assures that enough bytes are output
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317 in order for the decompressor to finish the block before the empty fixed
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318 codes block.
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319
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320 If flush is set to Z_BLOCK, a deflate block is completed and emitted, as
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321 for Z_SYNC_FLUSH, but the output is not aligned on a byte boundary, and up to
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322 seven bits of the current block are held to be written as the next byte after
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323 the next deflate block is completed. In this case, the decompressor may not
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324 be provided enough bits at this point in order to complete decompression of
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325 the data provided so far to the compressor. It may need to wait for the next
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326 block to be emitted. This is for advanced applications that need to control
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327 the emission of deflate blocks.
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328
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329 If flush is set to Z_FULL_FLUSH, all output is flushed as with
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330 Z_SYNC_FLUSH, and the compression state is reset so that decompression can
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331 restart from this point if previous compressed data has been damaged or if
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332 random access is desired. Using Z_FULL_FLUSH too often can seriously degrade
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333 compression.
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334
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335 If deflate returns with avail_out == 0, this function must be called again
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336 with the same value of the flush parameter and more output space (updated
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337 avail_out), until the flush is complete (deflate returns with non-zero
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338 avail_out). In the case of a Z_FULL_FLUSH or Z_SYNC_FLUSH, make sure that
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339 avail_out is greater than six to avoid repeated flush markers due to
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340 avail_out == 0 on return.
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341
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342 If the parameter flush is set to Z_FINISH, pending input is processed,
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343 pending output is flushed and deflate returns with Z_STREAM_END if there was
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344 enough output space. If deflate returns with Z_OK or Z_BUF_ERROR, this
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345 function must be called again with Z_FINISH and more output space (updated
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346 avail_out) but no more input data, until it returns with Z_STREAM_END or an
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347 error. After deflate has returned Z_STREAM_END, the only possible operations
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348 on the stream are deflateReset or deflateEnd.
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349
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350 Z_FINISH can be used in the first deflate call after deflateInit if all the
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351 compression is to be done in a single step. In order to complete in one
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352 call, avail_out must be at least the value returned by deflateBound (see
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353 below). Then deflate is guaranteed to return Z_STREAM_END. If not enough
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354 output space is provided, deflate will not return Z_STREAM_END, and it must
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355 be called again as described above.
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356
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357 deflate() sets strm->adler to the Adler-32 checksum of all input read
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358 so far (that is, total_in bytes). If a gzip stream is being generated, then
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359 strm->adler will be the CRC-32 checksum of the input read so far. (See
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360 deflateInit2 below.)
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361
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362 deflate() may update strm->data_type if it can make a good guess about
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363 the input data type (Z_BINARY or Z_TEXT). If in doubt, the data is
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364 considered binary. This field is only for information purposes and does not
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365 affect the compression algorithm in any manner.
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366
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367 deflate() returns Z_OK if some progress has been made (more input
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368 processed or more output produced), Z_STREAM_END if all input has been
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369 consumed and all output has been produced (only when flush is set to
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370 Z_FINISH), Z_STREAM_ERROR if the stream state was inconsistent (for example
|
|
|
371 if next_in or next_out was Z_NULL or the state was inadvertently written over
|
|
|
372 by the application), or Z_BUF_ERROR if no progress is possible (for example
|
|
|
373 avail_in or avail_out was zero). Note that Z_BUF_ERROR is not fatal, and
|
|
|
374 deflate() can be called again with more input and more output space to
|
|
|
375 continue compressing.
|
|
|
376 */
|
|
|
377
|
|
|
378
|
|
|
379 int deflateEnd(z_streamp strm);
|
|
|
380 /*
|
|
|
381 All dynamically allocated data structures for this stream are freed.
|
|
|
382 This function discards any unprocessed input and does not flush any pending
|
|
|
383 output.
|
|
|
384
|
|
|
385 deflateEnd returns Z_OK if success, Z_STREAM_ERROR if the
|
|
|
386 stream state was inconsistent, Z_DATA_ERROR if the stream was freed
|
|
|
387 prematurely (some input or output was discarded). In the error case, msg
|
|
|
388 may be set but then points to a static string (which must not be
|
|
|
389 deallocated).
|
|
|
390 */
|
|
|
391
|
|
|
392
|
|
|
393 int inflateInit(z_streamp strm)
|
|
|
394 {
|
|
|
395 return inflateInit_(strm, ZLIB_VERSION.ptr, z_stream.sizeof);
|
|
|
396 }
|
|
|
397 /*
|
|
|
398 Initializes the internal stream state for decompression. The fields
|
|
|
399 next_in, avail_in, zalloc, zfree and opaque must be initialized before by
|
|
|
400 the caller. In the current version of inflate, the provided input is not
|
|
|
401 read or consumed. The allocation of a sliding window will be deferred to
|
|
|
402 the first call of inflate (if the decompression does not complete on the
|
|
|
403 first call). If zalloc and zfree are set to Z_NULL, inflateInit updates
|
|
|
404 them to use default allocation functions.
|
|
|
405
|
|
|
406 inflateInit returns Z_OK if success, Z_MEM_ERROR if there was not enough
|
|
|
407 memory, Z_VERSION_ERROR if the zlib library version is incompatible with the
|
|
|
408 version assumed by the caller, or Z_STREAM_ERROR if the parameters are
|
|
|
409 invalid, such as a null pointer to the structure. msg is set to null if
|
|
|
410 there is no error message. inflateInit does not perform any decompression.
|
|
|
411 Actual decompression will be done by inflate(). So next_in, and avail_in,
|
|
|
412 next_out, and avail_out are unused and unchanged. The current
|
|
|
413 implementation of inflateInit() does not process any header information --
|
|
|
414 that is deferred until inflate() is called.
|
|
|
415 */
|
|
|
416
|
|
|
417
|
|
|
418 int inflate(z_streamp strm, int flush);
|
|
|
419 /*
|
|
|
420 inflate decompresses as much data as possible, and stops when the input
|
|
|
421 buffer becomes empty or the output buffer becomes full. It may introduce
|
|
|
422 some output latency (reading input without producing any output) except when
|
|
|
423 forced to flush.
|
|
|
424
|
|
|
425 The detailed semantics are as follows. inflate performs one or both of the
|
|
|
426 following actions:
|
|
|
427
|
|
|
428 - Decompress more input starting at next_in and update next_in and avail_in
|
|
|
429 accordingly. If not all input can be processed (because there is not
|
|
|
430 enough room in the output buffer), then next_in and avail_in are updated
|
|
|
431 accordingly, and processing will resume at this point for the next call of
|
|
|
432 inflate().
|
|
|
433
|
|
|
434 - Generate more output starting at next_out and update next_out and avail_out
|
|
|
435 accordingly. inflate() provides as much output as possible, until there is
|
|
|
436 no more input data or no more space in the output buffer (see below about
|
|
|
437 the flush parameter).
|
|
|
438
|
|
|
439 Before the call of inflate(), the application should ensure that at least
|
|
|
440 one of the actions is possible, by providing more input and/or consuming more
|
|
|
441 output, and updating the next_* and avail_* values accordingly. If the
|
|
|
442 caller of inflate() does not provide both available input and available
|
|
|
443 output space, it is possible that there will be no progress made. The
|
|
|
444 application can consume the uncompressed output when it wants, for example
|
|
|
445 when the output buffer is full (avail_out == 0), or after each call of
|
|
|
446 inflate(). If inflate returns Z_OK and with zero avail_out, it must be
|
|
|
447 called again after making room in the output buffer because there might be
|
|
|
448 more output pending.
|
|
|
449
|
|
|
450 The flush parameter of inflate() can be Z_NO_FLUSH, Z_SYNC_FLUSH, Z_FINISH,
|
|
|
451 Z_BLOCK, or Z_TREES. Z_SYNC_FLUSH requests that inflate() flush as much
|
|
|
452 output as possible to the output buffer. Z_BLOCK requests that inflate()
|
|
|
453 stop if and when it gets to the next deflate block boundary. When decoding
|
|
|
454 the zlib or gzip format, this will cause inflate() to return immediately
|
|
|
455 after the header and before the first block. When doing a raw inflate,
|
|
|
456 inflate() will go ahead and process the first block, and will return when it
|
|
|
457 gets to the end of that block, or when it runs out of data.
|
|
|
458
|
|
|
459 The Z_BLOCK option assists in appending to or combining deflate streams.
|
|
|
460 To assist in this, on return inflate() always sets strm->data_type to the
|
|
|
461 number of unused bits in the last byte taken from strm->next_in, plus 64 if
|
|
|
462 inflate() is currently decoding the last block in the deflate stream, plus
|
|
|
463 128 if inflate() returned immediately after decoding an end-of-block code or
|
|
|
464 decoding the complete header up to just before the first byte of the deflate
|
|
|
465 stream. The end-of-block will not be indicated until all of the uncompressed
|
|
|
466 data from that block has been written to strm->next_out. The number of
|
|
|
467 unused bits may in general be greater than seven, except when bit 7 of
|
|
|
468 data_type is set, in which case the number of unused bits will be less than
|
|
|
469 eight. data_type is set as noted here every time inflate() returns for all
|
|
|
470 flush options, and so can be used to determine the amount of currently
|
|
|
471 consumed input in bits.
|
|
|
472
|
|
|
473 The Z_TREES option behaves as Z_BLOCK does, but it also returns when the
|
|
|
474 end of each deflate block header is reached, before any actual data in that
|
|
|
475 block is decoded. This allows the caller to determine the length of the
|
|
|
476 deflate block header for later use in random access within a deflate block.
|
|
|
477 256 is added to the value of strm->data_type when inflate() returns
|
|
|
478 immediately after reaching the end of the deflate block header.
|
|
|
479
|
|
|
480 inflate() should normally be called until it returns Z_STREAM_END or an
|
|
|
481 error. However if all decompression is to be performed in a single step (a
|
|
|
482 single call of inflate), the parameter flush should be set to Z_FINISH. In
|
|
|
483 this case all pending input is processed and all pending output is flushed;
|
|
|
484 avail_out must be large enough to hold all of the uncompressed data for the
|
|
|
485 operation to complete. (The size of the uncompressed data may have been
|
|
|
486 saved by the compressor for this purpose.) The use of Z_FINISH is not
|
|
|
487 required to perform an inflation in one step. However it may be used to
|
|
|
488 inform inflate that a faster approach can be used for the single inflate()
|
|
|
489 call. Z_FINISH also informs inflate to not maintain a sliding window if the
|
|
|
490 stream completes, which reduces inflate's memory footprint. If the stream
|
|
|
491 does not complete, either because not all of the stream is provided or not
|
|
|
492 enough output space is provided, then a sliding window will be allocated and
|
|
|
493 inflate() can be called again to continue the operation as if Z_NO_FLUSH had
|
|
|
494 been used.
|
|
|
495
|
|
|
496 In this implementation, inflate() always flushes as much output as
|
|
|
497 possible to the output buffer, and always uses the faster approach on the
|
|
|
498 first call. So the effects of the flush parameter in this implementation are
|
|
|
499 on the return value of inflate() as noted below, when inflate() returns early
|
|
|
500 when Z_BLOCK or Z_TREES is used, and when inflate() avoids the allocation of
|
|
|
501 memory for a sliding window when Z_FINISH is used.
|
|
|
502
|
|
|
503 If a preset dictionary is needed after this call (see inflateSetDictionary
|
|
|
504 below), inflate sets strm->adler to the Adler-32 checksum of the dictionary
|
|
|
505 chosen by the compressor and returns Z_NEED_DICT; otherwise it sets
|
|
|
506 strm->adler to the Adler-32 checksum of all output produced so far (that is,
|
|
|
507 total_out bytes) and returns Z_OK, Z_STREAM_END or an error code as described
|
|
|
508 below. At the end of the stream, inflate() checks that its computed Adler-32
|
|
|
509 checksum is equal to that saved by the compressor and returns Z_STREAM_END
|
|
|
510 only if the checksum is correct.
|
|
|
511
|
|
|
512 inflate() can decompress and check either zlib-wrapped or gzip-wrapped
|
|
|
513 deflate data. The header type is detected automatically, if requested when
|
|
|
514 initializing with inflateInit2(). Any information contained in the gzip
|
|
|
515 header is not retained unless inflateGetHeader() is used. When processing
|
|
|
516 gzip-wrapped deflate data, strm->adler32 is set to the CRC-32 of the output
|
|
|
517 produced so far. The CRC-32 is checked against the gzip trailer, as is the
|
|
|
518 uncompressed length, modulo 2^32.
|
|
|
519
|
|
|
520 inflate() returns Z_OK if some progress has been made (more input processed
|
|
|
521 or more output produced), Z_STREAM_END if the end of the compressed data has
|
|
|
522 been reached and all uncompressed output has been produced, Z_NEED_DICT if a
|
|
|
523 preset dictionary is needed at this point, Z_DATA_ERROR if the input data was
|
|
|
524 corrupted (input stream not conforming to the zlib format or incorrect check
|
|
|
525 value, in which case strm->msg points to a string with a more specific
|
|
|
526 error), Z_STREAM_ERROR if the stream structure was inconsistent (for example
|
|
|
527 next_in or next_out was Z_NULL, or the state was inadvertently written over
|
|
|
528 by the application), Z_MEM_ERROR if there was not enough memory, Z_BUF_ERROR
|
|
|
529 if no progress was possible or if there was not enough room in the output
|
|
|
530 buffer when Z_FINISH is used. Note that Z_BUF_ERROR is not fatal, and
|
|
|
531 inflate() can be called again with more input and more output space to
|
|
|
532 continue decompressing. If Z_DATA_ERROR is returned, the application may
|
|
|
533 then call inflateSync() to look for a good compression block if a partial
|
|
|
534 recovery of the data is to be attempted.
|
|
|
535 */
|
|
|
536
|
|
|
537
|
|
|
538 int inflateEnd(z_streamp strm);
|
|
|
539 /*
|
|
|
540 All dynamically allocated data structures for this stream are freed.
|
|
|
541 This function discards any unprocessed input and does not flush any pending
|
|
|
542 output.
|
|
|
543
|
|
|
544 inflateEnd returns Z_OK if success, or Z_STREAM_ERROR if the stream state
|
|
|
545 was inconsistent.
|
|
|
546 */
|
|
|
547
|
|
|
548 /* Advanced functions */
|
|
|
549
|
|
|
550 /*
|
|
|
551 The following functions are needed only in some special applications.
|
|
|
552 */
|
|
|
553
|
|
|
554 int deflateInit2(z_streamp strm,
|
|
|
555 int level,
|
|
|
556 int method,
|
|
|
557 int windowBits,
|
|
|
558 int memLevel,
|
|
|
559 int strategy)
|
|
|
560 {
|
|
|
561 return deflateInit2_(strm, level, method, windowBits, memLevel,
|
|
|
562 strategy, ZLIB_VERSION.ptr, z_stream.sizeof);
|
|
|
563 }
|
|
|
564 /*
|
|
|
565 This is another version of deflateInit with more compression options. The
|
|
|
566 fields next_in, zalloc, zfree and opaque must be initialized before by the
|
|
|
567 caller.
|
|
|
568
|
|
|
569 The method parameter is the compression method. It must be Z_DEFLATED in
|
|
|
570 this version of the library.
|
|
|
571
|
|
|
572 The windowBits parameter is the base two logarithm of the window size
|
|
|
573 (the size of the history buffer). It should be in the range 8 .. 15 for this
|
|
|
574 version of the library. Larger values of this parameter result in better
|
|
|
575 compression at the expense of memory usage. The default value is 15 if
|
|
|
576 deflateInit is used instead.
|
|
|
577
|
|
|
578 For the current implementation of deflate(), a windowBits value of 8 (a
|
|
|
579 window size of 256 bytes) is not supported. As a result, a request for 8
|
|
|
580 will result in 9 (a 512-byte window). In that case, providing 8 to
|
|
|
581 inflateInit2() will result in an error when the zlib header with 9 is
|
|
|
582 checked against the initialization of inflate(). The remedy is to not use 8
|
|
|
583 with deflateInit2() with this initialization, or at least in that case use 9
|
|
|
584 with inflateInit2().
|
|
|
585
|
|
|
586 windowBits can also be -8..-15 for raw deflate. In this case, -windowBits
|
|
|
587 determines the window size. deflate() will then generate raw deflate data
|
|
|
588 with no zlib header or trailer, and will not compute a check value.
|
|
|
589
|
|
|
590 windowBits can also be greater than 15 for optional gzip encoding. Add
|
|
|
591 16 to windowBits to write a simple gzip header and trailer around the
|
|
|
592 compressed data instead of a zlib wrapper. The gzip header will have no
|
|
|
593 file name, no extra data, no comment, no modification time (set to zero), no
|
|
|
594 header crc, and the operating system will be set to the appropriate value,
|
|
|
595 if the operating system was determined at compile time. If a gzip stream is
|
|
|
596 being written, strm->adler is a CRC-32 instead of an Adler-32.
|
|
|
597
|
|
|
598 For raw deflate or gzip encoding, a request for a 256-byte window is
|
|
|
599 rejected as invalid, since only the zlib header provides a means of
|
|
|
600 transmitting the window size to the decompressor.
|
|
|
601
|
|
|
602 The memLevel parameter specifies how much memory should be allocated
|
|
|
603 for the internal compression state. memLevel=1 uses minimum memory but is
|
|
|
604 slow and reduces compression ratio; memLevel=9 uses maximum memory for
|
|
|
605 optimal speed. The default value is 8. See zconf.h for total memory usage
|
|
|
606 as a function of windowBits and memLevel.
|
|
|
607
|
|
|
608 The strategy parameter is used to tune the compression algorithm. Use the
|
|
|
609 value Z_DEFAULT_STRATEGY for normal data, Z_FILTERED for data produced by a
|
|
|
610 filter (or predictor), Z_HUFFMAN_ONLY to force Huffman encoding only (no
|
|
|
611 string match), or Z_RLE to limit match distances to one (run-length
|
|
|
612 encoding). Filtered data consists mostly of small values with a somewhat
|
|
|
613 random distribution. In this case, the compression algorithm is tuned to
|
|
|
614 compress them better. The effect of Z_FILTERED is to force more Huffman
|
|
|
615 coding and less string matching; it is somewhat intermediate between
|
|
|
616 Z_DEFAULT_STRATEGY and Z_HUFFMAN_ONLY. Z_RLE is designed to be almost as
|
|
|
617 fast as Z_HUFFMAN_ONLY, but give better compression for PNG image data. The
|
|
|
618 strategy parameter only affects the compression ratio but not the
|
|
|
619 correctness of the compressed output even if it is not set appropriately.
|
|
|
620 Z_FIXED prevents the use of dynamic Huffman codes, allowing for a simpler
|
|
|
621 decoder for special applications.
|
|
|
622
|
|
|
623 deflateInit2 returns Z_OK if success, Z_MEM_ERROR if there was not enough
|
|
|
624 memory, Z_STREAM_ERROR if any parameter is invalid (such as an invalid
|
|
|
625 method), or Z_VERSION_ERROR if the zlib library version (zlib_version) is
|
|
|
626 incompatible with the version assumed by the caller (ZLIB_VERSION). msg is
|
|
|
627 set to null if there is no error message. deflateInit2 does not perform any
|
|
|
628 compression: this will be done by deflate().
|
|
|
629 */
|
|
|
630
|
|
|
631 int deflateSetDictionary(z_streamp strm, const(ubyte)* dictionary, uint dictLength);
|
|
|
632 /*
|
|
|
633 Initializes the compression dictionary from the given byte sequence
|
|
|
634 without producing any compressed output. When using the zlib format, this
|
|
|
635 function must be called immediately after deflateInit, deflateInit2 or
|
|
|
636 deflateReset, and before any call of deflate. When doing raw deflate, this
|
|
|
637 function must be called either before any call of deflate, or immediately
|
|
|
638 after the completion of a deflate block, i.e. after all input has been
|
|
|
639 consumed and all output has been delivered when using any of the flush
|
|
|
640 options Z_BLOCK, Z_PARTIAL_FLUSH, Z_SYNC_FLUSH, or Z_FULL_FLUSH. The
|
|
|
641 compressor and decompressor must use exactly the same dictionary (see
|
|
|
642 inflateSetDictionary).
|
|
|
643
|
|
|
644 The dictionary should consist of strings (byte sequences) that are likely
|
|
|
645 to be encountered later in the data to be compressed, with the most commonly
|
|
|
646 used strings preferably put towards the end of the dictionary. Using a
|
|
|
647 dictionary is most useful when the data to be compressed is short and can be
|
|
|
648 predicted with good accuracy; the data can then be compressed better than
|
|
|
649 with the default empty dictionary.
|
|
|
650
|
|
|
651 Depending on the size of the compression data structures selected by
|
|
|
652 deflateInit or deflateInit2, a part of the dictionary may in effect be
|
|
|
653 discarded, for example if the dictionary is larger than the window size
|
|
|
654 provided in deflateInit or deflateInit2. Thus the strings most likely to be
|
|
|
655 useful should be put at the end of the dictionary, not at the front. In
|
|
|
656 addition, the current implementation of deflate will use at most the window
|
|
|
657 size minus 262 bytes of the provided dictionary.
|
|
|
658
|
|
|
659 Upon return of this function, strm->adler is set to the Adler-32 value
|
|
|
660 of the dictionary; the decompressor may later use this value to determine
|
|
|
661 which dictionary has been used by the compressor. (The Adler-32 value
|
|
|
662 applies to the whole dictionary even if only a subset of the dictionary is
|
|
|
663 actually used by the compressor.) If a raw deflate was requested, then the
|
|
|
664 Adler-32 value is not computed and strm->adler is not set.
|
|
|
665
|
|
|
666 deflateSetDictionary returns Z_OK if success, or Z_STREAM_ERROR if a
|
|
|
667 parameter is invalid (e.g. dictionary being Z_NULL) or the stream state is
|
|
|
668 inconsistent (for example if deflate has already been called for this stream
|
|
|
669 or if not at a block boundary for raw deflate). deflateSetDictionary does
|
|
|
670 not perform any compression: this will be done by deflate().
|
|
|
671 */
|
|
|
672
|
|
|
673 int deflateGetDictionary(z_streamp strm, ubyte *dictionary, uint dictLength);
|
|
|
674 /*
|
|
|
675 Returns the sliding dictionary being maintained by deflate. dictLength is
|
|
|
676 set to the number of bytes in the dictionary, and that many bytes are copied
|
|
|
677 to dictionary. dictionary must have enough space, where 32768 bytes is
|
|
|
678 always enough. If deflateGetDictionary() is called with dictionary equal to
|
|
|
679 Z_NULL, then only the dictionary length is returned, and nothing is copied.
|
|
|
680 Similary, if dictLength is Z_NULL, then it is not set.
|
|
|
681
|
|
|
682 deflateGetDictionary() may return a length less than the window size, even
|
|
|
683 when more than the window size in input has been provided. It may return up
|
|
|
684 to 258 bytes less in that case, due to how zlib's implementation of deflate
|
|
|
685 manages the sliding window and lookahead for matches, where matches can be
|
|
|
686 up to 258 bytes long. If the application needs the last window-size bytes of
|
|
|
687 input, then that would need to be saved by the application outside of zlib.
|
|
|
688
|
|
|
689 deflateGetDictionary returns Z_OK on success, or Z_STREAM_ERROR if the
|
|
|
690 stream state is inconsistent.
|
|
|
691 */
|
|
|
692
|
|
|
693 int deflateCopy(z_streamp dest, z_streamp source);
|
|
|
694 /*
|
|
|
695 Sets the destination stream as a complete copy of the source stream.
|
|
|
696
|
|
|
697 This function can be useful when several compression strategies will be
|
|
|
698 tried, for example when there are several ways of pre-processing the input
|
|
|
699 data with a filter. The streams that will be discarded should then be freed
|
|
|
700 by calling deflateEnd. Note that deflateCopy duplicates the internal
|
|
|
701 compression state which can be quite large, so this strategy is slow and can
|
|
|
702 consume lots of memory.
|
|
|
703
|
|
|
704 deflateCopy returns Z_OK if success, Z_MEM_ERROR if there was not
|
|
|
705 enough memory, Z_STREAM_ERROR if the source stream state was inconsistent
|
|
|
706 (such as zalloc being Z_NULL). msg is left unchanged in both source and
|
|
|
707 destination.
|
|
|
708 */
|
|
|
709
|
|
|
710 int deflateReset(z_streamp strm);
|
|
|
711 /*
|
|
|
712 This function is equivalent to deflateEnd followed by deflateInit, but
|
|
|
713 does not free and reallocate the internal compression state. The stream
|
|
|
714 will leave the compression level and any other attributes that may have been
|
|
|
715 set unchanged.
|
|
|
716
|
|
|
717 deflateReset returns Z_OK if success, or Z_STREAM_ERROR if the source
|
|
|
718 stream state was inconsistent (such as zalloc or state being Z_NULL).
|
|
|
719 */
|
|
|
720
|
|
|
721 int deflateParams(z_streamp strm, int level, int strategy);
|
|
|
722 /*
|
|
|
723 Dynamically update the compression level and compression strategy. The
|
|
|
724 interpretation of level and strategy is as in deflateInit2(). This can be
|
|
|
725 used to switch between compression and straight copy of the input data, or
|
|
|
726 to switch to a different kind of input data requiring a different strategy.
|
|
|
727 If the compression approach (which is a function of the level) or the
|
|
|
728 strategy is changed, and if any input has been consumed in a previous
|
|
|
729 deflate() call, then the input available so far is compressed with the old
|
|
|
730 level and strategy using deflate(strm, Z_BLOCK). There are three approaches
|
|
|
731 for the compression levels 0, 1 .. 3, and 4 .. 9 respectively. The new level
|
|
|
732 and strategy will take effect at the next call of deflate().
|
|
|
733
|
|
|
734 If a deflate(strm, Z_BLOCK) is performed by deflateParams(), and it does
|
|
|
735 not have enough output space to complete, then the parameter change will not
|
|
|
736 take effect. In this case, deflateParams() can be called again with the
|
|
|
737 same parameters and more output space to try again.
|
|
|
738
|
|
|
739 In order to assure a change in the parameters on the first try, the
|
|
|
740 deflate stream should be flushed using deflate() with Z_BLOCK or other flush
|
|
|
741 request until strm.avail_out is not zero, before calling deflateParams().
|
|
|
742 Then no more input data should be provided before the deflateParams() call.
|
|
|
743 If this is done, the old level and strategy will be applied to the data
|
|
|
744 compressed before deflateParams(), and the new level and strategy will be
|
|
|
745 applied to the the data compressed after deflateParams().
|
|
|
746
|
|
|
747 deflateParams returns Z_OK on success, Z_STREAM_ERROR if the source stream
|
|
|
748 state was inconsistent or if a parameter was invalid, or Z_BUF_ERROR if
|
|
|
749 there was not enough output space to complete the compression of the
|
|
|
750 available input data before a change in the strategy or approach. Note that
|
|
|
751 in the case of a Z_BUF_ERROR, the parameters are not changed. A return
|
|
|
752 value of Z_BUF_ERROR is not fatal, in which case deflateParams() can be
|
|
|
753 retried with more output space.
|
|
|
754 */
|
|
|
755
|
|
|
756 int deflateTune(z_streamp strm, int good_length, int max_lazy, int nice_length,
|
|
|
757 int max_chain);
|
|
|
758 /*
|
|
|
759 Fine tune deflate's internal compression parameters. This should only be
|
|
|
760 used by someone who understands the algorithm used by zlib's deflate for
|
|
|
761 searching for the best matching string, and even then only by the most
|
|
|
762 fanatic optimizer trying to squeeze out the last compressed bit for their
|
|
|
763 specific input data. Read the deflate.c source code for the meaning of the
|
|
|
764 max_lazy, good_length, nice_length, and max_chain parameters.
|
|
|
765
|
|
|
766 deflateTune() can be called after deflateInit() or deflateInit2(), and
|
|
|
767 returns Z_OK on success, or Z_STREAM_ERROR for an invalid deflate stream.
|
|
|
768 */
|
|
|
769
|
|
|
770 size_t deflateBound(z_streamp strm, size_t sourceLen);
|
|
|
771 /*
|
|
|
772 deflateBound() returns an upper bound on the compressed size after
|
|
|
773 deflation of sourceLen bytes. It must be called after deflateInit() or
|
|
|
774 deflateInit2(), and after deflateSetHeader(), if used. This would be used
|
|
|
775 to allocate an output buffer for deflation in a single pass, and so would be
|
|
|
776 called before deflate(). If that first deflate() call is provided the
|
|
|
777 sourceLen input bytes, an output buffer allocated to the size returned by
|
|
|
778 deflateBound(), and the flush value Z_FINISH, then deflate() is guaranteed
|
|
|
779 to return Z_STREAM_END. Note that it is possible for the compressed size to
|
|
|
780 be larger than the value returned by deflateBound() if flush options other
|
|
|
781 than Z_FINISH or Z_NO_FLUSH are used.
|
|
|
782 */
|
|
|
783
|
|
|
784 int deflatePending(z_streamp strm, uint* pending, int* bits);
|
|
|
785 /*
|
|
|
786 deflatePending() returns the number of bytes and bits of output that have
|
|
|
787 been generated, but not yet provided in the available output. The bytes not
|
|
|
788 provided would be due to the available output space having being consumed.
|
|
|
789 The number of bits of output not provided are between 0 and 7, where they
|
|
|
790 await more bits to join them in order to fill out a full byte. If pending
|
|
|
791 or bits are Z_NULL, then those values are not set.
|
|
|
792
|
|
|
793 deflatePending returns Z_OK if success, or Z_STREAM_ERROR if the source
|
|
|
794 stream state was inconsistent.
|
|
|
795 */
|
|
|
796
|
|
|
797 int deflatePrime(z_streamp strm, int bits, int value);
|
|
|
798 /*
|
|
|
799 deflatePrime() inserts bits in the deflate output stream. The intent
|
|
|
800 is that this function is used to start off the deflate output with the bits
|
|
|
801 leftover from a previous deflate stream when appending to it. As such, this
|
|
|
802 function can only be used for raw deflate, and must be used before the first
|
|
|
803 deflate() call after a deflateInit2() or deflateReset(). bits must be less
|
|
|
804 than or equal to 16, and that many of the least significant bits of value
|
|
|
805 will be inserted in the output.
|
|
|
806
|
|
|
807 deflatePrime returns Z_OK if success, Z_BUF_ERROR if there was not enough
|
|
|
808 room in the internal buffer to insert the bits, or Z_STREAM_ERROR if the
|
|
|
809 source stream state was inconsistent.
|
|
|
810 */
|
|
|
811
|
|
|
812 int deflateSetHeader(z_streamp strm, gz_headerp head);
|
|
|
813 /*
|
|
|
814 deflateSetHeader() provides gzip header information for when a gzip
|
|
|
815 stream is requested by deflateInit2(). deflateSetHeader() may be called
|
|
|
816 after deflateInit2() or deflateReset() and before the first call of
|
|
|
817 deflate(). The text, time, os, extra field, name, and comment information
|
|
|
818 in the provided gz_header structure are written to the gzip header (xflag is
|
|
|
819 ignored -- the extra flags are set according to the compression level). The
|
|
|
820 caller must assure that, if not Z_NULL, name and comment are terminated with
|
|
|
821 a zero byte, and that if extra is not Z_NULL, that extra_len bytes are
|
|
|
822 available there. If hcrc is true, a gzip header crc is included. Note that
|
|
|
823 the current versions of the command-line version of gzip (up through version
|
|
|
824 1.3.x) do not support header crc's, and will report that it is a "multi-part
|
|
|
825 gzip file" and give up.
|
|
|
826
|
|
|
827 If deflateSetHeader is not used, the default gzip header has text false,
|
|
|
828 the time set to zero, and os set to 255, with no extra, name, or comment
|
|
|
829 fields. The gzip header is returned to the default state by deflateReset().
|
|
|
830
|
|
|
831 deflateSetHeader returns Z_OK if success, or Z_STREAM_ERROR if the source
|
|
|
832 stream state was inconsistent.
|
|
|
833 */
|
|
|
834
|
|
|
835 int inflateInit2(z_streamp strm, int windowBits)
|
|
|
836 {
|
|
|
837 return inflateInit2_(strm, windowBits, ZLIB_VERSION.ptr, z_stream.sizeof);
|
|
|
838 }
|
|
|
839 /*
|
|
|
840 This is another version of inflateInit with an extra parameter. The
|
|
|
841 fields next_in, avail_in, zalloc, zfree and opaque must be initialized
|
|
|
842 before by the caller.
|
|
|
843
|
|
|
844 The windowBits parameter is the base two logarithm of the maximum window
|
|
|
845 size (the size of the history buffer). It should be in the range 8 .. 15 for
|
|
|
846 this version of the library. The default value is 15 if inflateInit is used
|
|
|
847 instead. windowBits must be greater than or equal to the windowBits value
|
|
|
848 provided to deflateInit2() while compressing, or it must be equal to 15 if
|
|
|
849 deflateInit2() was not used. If a compressed stream with a larger window
|
|
|
850 size is given as input, inflate() will return with the error code
|
|
|
851 Z_DATA_ERROR instead of trying to allocate a larger window.
|
|
|
852
|
|
|
853 windowBits can also be zero to request that inflate use the window size in
|
|
|
854 the zlib header of the compressed stream.
|
|
|
855
|
|
|
856 windowBits can also be -8..-15 for raw inflate. In this case, -windowBits
|
|
|
857 determines the window size. inflate() will then process raw deflate data,
|
|
|
858 not looking for a zlib or gzip header, not generating a check value, and not
|
|
|
859 looking for any check values for comparison at the end of the stream. This
|
|
|
860 is for use with other formats that use the deflate compressed data format
|
|
|
861 such as zip. Those formats provide their own check values. If a custom
|
|
|
862 format is developed using the raw deflate format for compressed data, it is
|
|
|
863 recommended that a check value such as an Adler-32 or a CRC-32 be applied to
|
|
|
864 the uncompressed data as is done in the zlib, gzip, and zip formats. For
|
|
|
865 most applications, the zlib format should be used as is. Note that comments
|
|
|
866 above on the use in deflateInit2() applies to the magnitude of windowBits.
|
|
|
867
|
|
|
868 windowBits can also be greater than 15 for optional gzip decoding. Add
|
|
|
869 32 to windowBits to enable zlib and gzip decoding with automatic header
|
|
|
870 detection, or add 16 to decode only the gzip format (the zlib format will
|
|
|
871 return a Z_DATA_ERROR). If a gzip stream is being decoded, strm->adler is a
|
|
|
872 CRC-32 instead of an Adler-32. Unlike the gunzip utility and gzread() (see
|
|
|
873 below), inflate() will not automatically decode concatenated gzip streams.
|
|
|
874 inflate() will return Z_STREAM_END at the end of the gzip stream. The state
|
|
|
875 would need to be reset to continue decoding a subsequent gzip stream.
|
|
|
876
|
|
|
877 inflateInit2 returns Z_OK if success, Z_MEM_ERROR if there was not enough
|
|
|
878 memory, Z_VERSION_ERROR if the zlib library version is incompatible with the
|
|
|
879 version assumed by the caller, or Z_STREAM_ERROR if the parameters are
|
|
|
880 invalid, such as a null pointer to the structure. msg is set to null if
|
|
|
881 there is no error message. inflateInit2 does not perform any decompression
|
|
|
882 apart from possibly reading the zlib header if present: actual decompression
|
|
|
883 will be done by inflate(). (So next_in and avail_in may be modified, but
|
|
|
884 next_out and avail_out are unused and unchanged.) The current implementation
|
|
|
885 of inflateInit2() does not process any header information -- that is
|
|
|
886 deferred until inflate() is called.
|
|
|
887 */
|
|
|
888
|
|
|
889 int inflateSetDictionary(z_streamp strm, const(ubyte)* dictionary, uint dictLength);
|
|
|
890 /*
|
|
|
891 Initializes the decompression dictionary from the given uncompressed byte
|
|
|
892 sequence. This function must be called immediately after a call of inflate,
|
|
|
893 if that call returned Z_NEED_DICT. The dictionary chosen by the compressor
|
|
|
894 can be determined from the Adler-32 value returned by that call of inflate.
|
|
|
895 The compressor and decompressor must use exactly the same dictionary (see
|
|
|
896 deflateSetDictionary). For raw inflate, this function can be called at any
|
|
|
897 time to set the dictionary. If the provided dictionary is smaller than the
|
|
|
898 window and there is already data in the window, then the provided dictionary
|
|
|
899 will amend what's there. The application must insure that the dictionary
|
|
|
900 that was used for compression is provided.
|
|
|
901
|
|
|
902 inflateSetDictionary returns Z_OK if success, Z_STREAM_ERROR if a
|
|
|
903 parameter is invalid (e.g. dictionary being Z_NULL) or the stream state is
|
|
|
904 inconsistent, Z_DATA_ERROR if the given dictionary doesn't match the
|
|
|
905 expected one (incorrect Adler-32 value). inflateSetDictionary does not
|
|
|
906 perform any decompression: this will be done by subsequent calls of
|
|
|
907 inflate().
|
|
|
908 */
|
|
|
909
|
|
|
910 int inflateGetDictionary(z_streamp strm, ubyte* dictionary, uint* dictLength);
|
|
|
911 /*
|
|
|
912 Returns the sliding dictionary being maintained by inflate. dictLength is
|
|
|
913 set to the number of bytes in the dictionary, and that many bytes are copied
|
|
|
914 to dictionary. dictionary must have enough space, where 32768 bytes is
|
|
|
915 always enough. If inflateGetDictionary() is called with dictionary equal to
|
|
|
916 Z_NULL, then only the dictionary length is returned, and nothing is copied.
|
|
|
917 Similary, if dictLength is Z_NULL, then it is not set.
|
|
|
918
|
|
|
919 inflateGetDictionary returns Z_OK on success, or Z_STREAM_ERROR if the
|
|
|
920 stream state is inconsistent.
|
|
|
921 */
|
|
|
922
|
|
|
923 int inflateSync(z_streamp strm);
|
|
|
924 /*
|
|
|
925 Skips invalid compressed data until a possible full flush point (see above
|
|
|
926 for the description of deflate with Z_FULL_FLUSH) can be found, or until all
|
|
|
927 available input is skipped. No output is provided.
|
|
|
928
|
|
|
929 inflateSync searches for a 00 00 FF FF pattern in the compressed data.
|
|
|
930 All full flush points have this pattern, but not all occurrences of this
|
|
|
931 pattern are full flush points.
|
|
|
932
|
|
|
933 inflateSync returns Z_OK if a possible full flush point has been found,
|
|
|
934 Z_BUF_ERROR if no more input was provided, Z_DATA_ERROR if no flush point
|
|
|
935 has been found, or Z_STREAM_ERROR if the stream structure was inconsistent.
|
|
|
936 In the success case, the application may save the current current value of
|
|
|
937 total_in which indicates where valid compressed data was found. In the
|
|
|
938 error case, the application may repeatedly call inflateSync, providing more
|
|
|
939 input each time, until success or end of the input data.
|
|
|
940 */
|
|
|
941
|
|
|
942 int inflateCopy(z_streamp dest, z_streamp source);
|
|
|
943 /*
|
|
|
944 Sets the destination stream as a complete copy of the source stream.
|
|
|
945
|
|
|
946 This function can be useful when randomly accessing a large stream. The
|
|
|
947 first pass through the stream can periodically record the inflate state,
|
|
|
948 allowing restarting inflate at those points when randomly accessing the
|
|
|
949 stream.
|
|
|
950
|
|
|
951 inflateCopy returns Z_OK if success, Z_MEM_ERROR if there was not
|
|
|
952 enough memory, Z_STREAM_ERROR if the source stream state was inconsistent
|
|
|
953 (such as zalloc being Z_NULL). msg is left unchanged in both source and
|
|
|
954 destination.
|
|
|
955 */
|
|
|
956
|
|
|
957 int inflateReset(z_streamp strm);
|
|
|
958 /*
|
|
|
959 This function is equivalent to inflateEnd followed by inflateInit,
|
|
|
960 but does not free and reallocate the internal decompression state. The
|
|
|
961 stream will keep attributes that may have been set by inflateInit2.
|
|
|
962
|
|
|
963 inflateReset returns Z_OK if success, or Z_STREAM_ERROR if the source
|
|
|
964 stream state was inconsistent (such as zalloc or state being Z_NULL).
|
|
|
965 */
|
|
|
966
|
|
|
967 int inflateReset2(z_streamp strm, int windowBits);
|
|
|
968 /*
|
|
|
969 This function is the same as inflateReset, but it also permits changing
|
|
|
970 the wrap and window size requests. The windowBits parameter is interpreted
|
|
|
971 the same as it is for inflateInit2. If the window size is changed, then the
|
|
|
972 memory allocated for the window is freed, and the window will be reallocated
|
|
|
973 by inflate() if needed.
|
|
|
974
|
|
|
975 inflateReset2 returns Z_OK if success, or Z_STREAM_ERROR if the source
|
|
|
976 stream state was inconsistent (such as zalloc or state being Z_NULL), or if
|
|
|
977 the windowBits parameter is invalid.
|
|
|
978 */
|
|
|
979
|
|
|
980 int inflatePrime(z_streamp strm, int bits, int value);
|
|
|
981 /*
|
|
|
982 This function inserts bits in the inflate input stream. The intent is
|
|
|
983 that this function is used to start inflating at a bit position in the
|
|
|
984 middle of a byte. The provided bits will be used before any bytes are used
|
|
|
985 from next_in. This function should only be used with raw inflate, and
|
|
|
986 should be used before the first inflate() call after inflateInit2() or
|
|
|
987 inflateReset(). bits must be less than or equal to 16, and that many of the
|
|
|
988 least significant bits of value will be inserted in the input.
|
|
|
989
|
|
|
990 If bits is negative, then the input stream bit buffer is emptied. Then
|
|
|
991 inflatePrime() can be called again to put bits in the buffer. This is used
|
|
|
992 to clear out bits leftover after feeding inflate a block description prior
|
|
|
993 to feeding inflate codes.
|
|
|
994
|
|
|
995 inflatePrime returns Z_OK if success, or Z_STREAM_ERROR if the source
|
|
|
996 stream state was inconsistent.
|
|
|
997 */
|
|
|
998
|
|
|
999 c_long inflateMark(z_streamp strm);
|
|
|
1000 /*
|
|
|
1001 This function returns two values, one in the lower 16 bits of the return
|
|
|
1002 value, and the other in the remaining upper bits, obtained by shifting the
|
|
|
1003 return value down 16 bits. If the upper value is -1 and the lower value is
|
|
|
1004 zero, then inflate() is currently decoding information outside of a block.
|
|
|
1005 If the upper value is -1 and the lower value is non-zero, then inflate is in
|
|
|
1006 the middle of a stored block, with the lower value equaling the number of
|
|
|
1007 bytes from the input remaining to copy. If the upper value is not -1, then
|
|
|
1008 it is the number of bits back from the current bit position in the input of
|
|
|
1009 the code (literal or length/distance pair) currently being processed. In
|
|
|
1010 that case the lower value is the number of bytes already emitted for that
|
|
|
1011 code.
|
|
|
1012
|
|
|
1013 A code is being processed if inflate is waiting for more input to complete
|
|
|
1014 decoding of the code, or if it has completed decoding but is waiting for
|
|
|
1015 more output space to write the literal or match data.
|
|
|
1016
|
|
|
1017 inflateMark() is used to mark locations in the input data for random
|
|
|
1018 access, which may be at bit positions, and to note those cases where the
|
|
|
1019 output of a code may span boundaries of random access blocks. The current
|
|
|
1020 location in the input stream can be determined from avail_in and data_type
|
|
|
1021 as noted in the description for the Z_BLOCK flush parameter for inflate.
|
|
|
1022
|
|
|
1023 inflateMark returns the value noted above, or -65536 if the provided
|
|
|
1024 source stream state was inconsistent.
|
|
|
1025 */
|
|
|
1026
|
|
|
1027 int inflateGetHeader(z_streamp strm, gz_headerp head);
|
|
|
1028 /*
|
|
|
1029 inflateGetHeader() requests that gzip header information be stored in the
|
|
|
1030 provided gz_header structure. inflateGetHeader() may be called after
|
|
|
1031 inflateInit2() or inflateReset(), and before the first call of inflate().
|
|
|
1032 As inflate() processes the gzip stream, head->done is zero until the header
|
|
|
1033 is completed, at which time head->done is set to one. If a zlib stream is
|
|
|
1034 being decoded, then head->done is set to -1 to indicate that there will be
|
|
|
1035 no gzip header information forthcoming. Note that Z_BLOCK or Z_TREES can be
|
|
|
1036 used to force inflate() to return immediately after header processing is
|
|
|
1037 complete and before any actual data is decompressed.
|
|
|
1038
|
|
|
1039 The text, time, xflags, and os fields are filled in with the gzip header
|
|
|
1040 contents. hcrc is set to true if there is a header CRC. (The header CRC
|
|
|
1041 was valid if done is set to one.) If extra is not Z_NULL, then extra_max
|
|
|
1042 contains the maximum number of bytes to write to extra. Once done is true,
|
|
|
1043 extra_len contains the actual extra field length, and extra contains the
|
|
|
1044 extra field, or that field truncated if extra_max is less than extra_len.
|
|
|
1045 If name is not Z_NULL, then up to name_max characters are written there,
|
|
|
1046 terminated with a zero unless the length is greater than name_max. If
|
|
|
1047 comment is not Z_NULL, then up to comm_max characters are written there,
|
|
|
1048 terminated with a zero unless the length is greater than comm_max. When any
|
|
|
1049 of extra, name, or comment are not Z_NULL and the respective field is not
|
|
|
1050 present in the header, then that field is set to Z_NULL to signal its
|
|
|
1051 absence. This allows the use of deflateSetHeader() with the returned
|
|
|
1052 structure to duplicate the header. However if those fields are set to
|
|
|
1053 allocated memory, then the application will need to save those pointers
|
|
|
1054 elsewhere so that they can be eventually freed.
|
|
|
1055
|
|
|
1056 If inflateGetHeader is not used, then the header information is simply
|
|
|
1057 discarded. The header is always checked for validity, including the header
|
|
|
1058 CRC if present. inflateReset() will reset the process to discard the header
|
|
|
1059 information. The application would need to call inflateGetHeader() again to
|
|
|
1060 retrieve the header from the next gzip stream.
|
|
|
1061
|
|
|
1062 inflateGetHeader returns Z_OK if success, or Z_STREAM_ERROR if the source
|
|
|
1063 stream state was inconsistent.
|
|
|
1064 */
|
|
|
1065
|
|
|
1066
|
|
|
1067 int inflateBackInit(z_stream* strm, int windowBits, ubyte* window)
|
|
|
1068 {
|
|
|
1069 return inflateBackInit_(strm, windowBits, window, ZLIB_VERSION.ptr, z_stream.sizeof);
|
|
|
1070 }
|
|
|
1071 /*
|
|
|
1072 Initialize the internal stream state for decompression using inflateBack()
|
|
|
1073 calls. The fields zalloc, zfree and opaque in strm must be initialized
|
|
|
1074 before the call. If zalloc and zfree are Z_NULL, then the default library-
|
|
|
1075 derived memory allocation routines are used. windowBits is the base two
|
|
|
1076 logarithm of the window size, in the range 8 .. 15. window is a caller
|
|
|
1077 supplied buffer of that size. Except for special applications where it is
|
|
|
1078 assured that deflate was used with small window sizes, windowBits must be 15
|
|
|
1079 and a 32K byte window must be supplied to be able to decompress general
|
|
|
1080 deflate streams.
|
|
|
1081
|
|
|
1082 See inflateBack() for the usage of these routines.
|
|
|
1083
|
|
|
1084 inflateBackInit will return Z_OK on success, Z_STREAM_ERROR if any of
|
|
|
1085 the parameters are invalid, Z_MEM_ERROR if the internal state could not be
|
|
|
1086 allocated, or Z_VERSION_ERROR if the version of the library does not match
|
|
|
1087 the version of the header file.
|
|
|
1088 */
|
|
|
1089
|
|
|
1090 alias in_func = uint function(void*, ubyte**);
|
|
|
1091 alias out_func = int function(void*, ubyte*, uint);
|
|
|
1092
|
|
|
1093 int inflateBack(z_stream* strm,
|
|
|
1094 in_func f_in,
|
|
|
1095 void* in_desc,
|
|
|
1096 out_func f_out,
|
|
|
1097 void* out_desc);
|
|
|
1098 /*
|
|
|
1099 inflateBack() does a raw inflate with a single call using a call-back
|
|
|
1100 interface for input and output. This is potentially more efficient than
|
|
|
1101 inflate() for file i/o applications, in that it avoids copying between the
|
|
|
1102 output and the sliding window by simply making the window itself the output
|
|
|
1103 buffer. inflate() can be faster on modern CPUs when used with large
|
|
|
1104 buffers. inflateBack() trusts the application to not change the output
|
|
|
1105 buffer passed by the output function, at least until inflateBack() returns.
|
|
|
1106
|
|
|
1107 inflateBackInit() must be called first to allocate the internal state
|
|
|
1108 and to initialize the state with the user-provided window buffer.
|
|
|
1109 inflateBack() may then be used multiple times to inflate a complete, raw
|
|
|
1110 deflate stream with each call. inflateBackEnd() is then called to free the
|
|
|
1111 allocated state.
|
|
|
1112
|
|
|
1113 A raw deflate stream is one with no zlib or gzip header or trailer.
|
|
|
1114 This routine would normally be used in a utility that reads zip or gzip
|
|
|
1115 files and writes out uncompressed files. The utility would decode the
|
|
|
1116 header and process the trailer on its own, hence this routine expects only
|
|
|
1117 the raw deflate stream to decompress. This is different from the default
|
|
|
1118 behavior of inflate(), which expects a zlib header and trailer around the
|
|
|
1119 deflate stream.
|
|
|
1120
|
|
|
1121 inflateBack() uses two subroutines supplied by the caller that are then
|
|
|
1122 called by inflateBack() for input and output. inflateBack() calls those
|
|
|
1123 routines until it reads a complete deflate stream and writes out all of the
|
|
|
1124 uncompressed data, or until it encounters an error. The function's
|
|
|
1125 parameters and return types are defined above in the in_func and out_func
|
|
|
1126 typedefs. inflateBack() will call in(in_desc, &buf) which should return the
|
|
|
1127 number of bytes of provided input, and a pointer to that input in buf. If
|
|
|
1128 there is no input available, in() must return zero -- buf is ignored in that
|
|
|
1129 case -- and inflateBack() will return a buffer error. inflateBack() will
|
|
|
1130 call out(out_desc, buf, len) to write the uncompressed data buf[0 .. len-1].
|
|
|
1131 out() should return zero on success, or non-zero on failure. If out()
|
|
|
1132 returns non-zero, inflateBack() will return with an error. Neither in() nor
|
|
|
1133 out() are permitted to change the contents of the window provided to
|
|
|
1134 inflateBackInit(), which is also the buffer that out() uses to write from.
|
|
|
1135 The length written by out() will be at most the window size. Any non-zero
|
|
|
1136 amount of input may be provided by in().
|
|
|
1137
|
|
|
1138 For convenience, inflateBack() can be provided input on the first call by
|
|
|
1139 setting strm->next_in and strm->avail_in. If that input is exhausted, then
|
|
|
1140 in() will be called. Therefore strm->next_in must be initialized before
|
|
|
1141 calling inflateBack(). If strm->next_in is Z_NULL, then in() will be called
|
|
|
1142 immediately for input. If strm->next_in is not Z_NULL, then strm->avail_in
|
|
|
1143 must also be initialized, and then if strm->avail_in is not zero, input will
|
|
|
1144 initially be taken from strm->next_in[0 .. strm->avail_in - 1].
|
|
|
1145
|
|
|
1146 The in_desc and out_desc parameters of inflateBack() is passed as the
|
|
|
1147 first parameter of in() and out() respectively when they are called. These
|
|
|
1148 descriptors can be optionally used to pass any information that the caller-
|
|
|
1149 supplied in() and out() functions need to do their job.
|
|
|
1150
|
|
|
1151 On return, inflateBack() will set strm->next_in and strm->avail_in to
|
|
|
1152 pass back any unused input that was provided by the last in() call. The
|
|
|
1153 return values of inflateBack() can be Z_STREAM_END on success, Z_BUF_ERROR
|
|
|
1154 if in() or out() returned an error, Z_DATA_ERROR if there was a format error
|
|
|
1155 in the deflate stream (in which case strm->msg is set to indicate the nature
|
|
|
1156 of the error), or Z_STREAM_ERROR if the stream was not properly initialized.
|
|
|
1157 In the case of Z_BUF_ERROR, an input or output error can be distinguished
|
|
|
1158 using strm->next_in which will be Z_NULL only if in() returned an error. If
|
|
|
1159 strm->next_in is not Z_NULL, then the Z_BUF_ERROR was due to out() returning
|
|
|
1160 non-zero. (in() will always be called before out(), so strm->next_in is
|
|
|
1161 assured to be defined if out() returns non-zero.) Note that inflateBack()
|
|
|
1162 cannot return Z_OK.
|
|
|
1163 */
|
|
|
1164
|
|
|
1165 int inflateBackEnd(z_stream* strm);
|
|
|
1166 /*
|
|
|
1167 All memory allocated by inflateBackInit() is freed.
|
|
|
1168
|
|
|
1169 inflateBackEnd() returns Z_OK on success, or Z_STREAM_ERROR if the stream
|
|
|
1170 state was inconsistent.
|
|
|
1171 */
|
|
|
1172
|
|
|
1173 uint zlibCompileFlags();
|
|
|
1174 /* Return flags indicating compile-time options.
|
|
|
1175
|
|
|
1176 Type sizes, two bits each, 00 = 16 bits, 01 = 32, 10 = 64, 11 = other:
|
|
|
1177 1.0: size of uInt
|
|
|
1178 3.2: size of uLong
|
|
|
1179 5.4: size of voidpf (pointer)
|
|
|
1180 7.6: size of z_off_t
|
|
|
1181
|
|
|
1182 Compiler, assembler, and debug options:
|
|
|
1183 8: ZLIB_DEBUG
|
|
|
1184 9: ASMV or ASMINF -- use ASM code
|
|
|
1185 10: ZLIB_WINAPI -- exported functions use the WINAPI calling convention
|
|
|
1186 11: 0 (reserved)
|
|
|
1187
|
|
|
1188 One-time table building (smaller code, but not thread-safe if true):
|
|
|
1189 12: BUILDFIXED -- build static block decoding tables when needed
|
|
|
1190 13: DYNAMIC_CRC_TABLE -- build CRC calculation tables when needed
|
|
|
1191 14,15: 0 (reserved)
|
|
|
1192
|
|
|
1193 Library content (indicates missing functionality):
|
|
|
1194 16: NO_GZCOMPRESS -- gz* functions cannot compress (to avoid linking
|
|
|
1195 deflate code when not needed)
|
|
|
1196 17: NO_GZIP -- deflate can't write gzip streams, and inflate can't detect
|
|
|
1197 and decode gzip streams (to avoid linking crc code)
|
|
|
1198 18-19: 0 (reserved)
|
|
|
1199
|
|
|
1200 Operation variations (changes in library functionality):
|
|
|
1201 20: PKZIP_BUG_WORKAROUND -- slightly more permissive inflate
|
|
|
1202 21: FASTEST -- deflate algorithm with only one, lowest compression level
|
|
|
1203 22,23: 0 (reserved)
|
|
|
1204
|
|
|
1205 The sprintf variant used by gzprintf (zero is best):
|
|
|
1206 24: 0 = vs*, 1 = s* -- 1 means limited to 20 arguments after the format
|
|
|
1207 25: 0 = *nprintf, 1 = *printf -- 1 means gzprintf() not secure!
|
|
|
1208 26: 0 = returns value, 1 = void -- 1 means inferred string length returned
|
|
|
1209
|
|
|
1210 Remainder:
|
|
|
1211 27-31: 0 (reserved)
|
|
|
1212 */
|
|
|
1213
|
|
|
1214 /* utility functions */
|
|
|
1215
|
|
|
1216 /*
|
|
|
1217 The following utility functions are implemented on top of the basic
|
|
|
1218 stream-oriented functions. To simplify the interface, some default options
|
|
|
1219 are assumed (compression level and memory usage, standard memory allocation
|
|
|
1220 functions). The source code of these utility functions can be modified if
|
|
|
1221 you need special options.
|
|
|
1222 */
|
|
|
1223
|
|
|
1224 int compress(ubyte* dest,
|
|
|
1225 size_t* destLen,
|
|
|
1226 const(ubyte)* source,
|
|
|
1227 size_t sourceLen);
|
|
|
1228 /*
|
|
|
1229 Compresses the source buffer into the destination buffer. sourceLen is
|
|
|
1230 the byte length of the source buffer. Upon entry, destLen is the total size
|
|
|
1231 of the destination buffer, which must be at least the value returned by
|
|
|
1232 compressBound(sourceLen). Upon exit, destLen is the actual size of the
|
|
|
1233 compressed data. compress() is equivalent to compress2() with a level
|
|
|
1234 parameter of Z_DEFAULT_COMPRESSION.
|
|
|
1235
|
|
|
1236 compress returns Z_OK if success, Z_MEM_ERROR if there was not
|
|
|
1237 enough memory, Z_BUF_ERROR if there was not enough room in the output
|
|
|
1238 buffer.
|
|
|
1239 */
|
|
|
1240
|
|
|
1241 int compress2(ubyte* dest,
|
|
|
1242 size_t* destLen,
|
|
|
1243 const(ubyte)* source,
|
|
|
1244 size_t sourceLen,
|
|
|
1245 int level);
|
|
|
1246 /*
|
|
|
1247 Compresses the source buffer into the destination buffer. The level
|
|
|
1248 parameter has the same meaning as in deflateInit. sourceLen is the byte
|
|
|
1249 length of the source buffer. Upon entry, destLen is the total size of the
|
|
|
1250 destination buffer, which must be at least the value returned by
|
|
|
1251 compressBound(sourceLen). Upon exit, destLen is the actual size of the
|
|
|
1252 compressed data.
|
|
|
1253
|
|
|
1254 compress2 returns Z_OK if success, Z_MEM_ERROR if there was not enough
|
|
|
1255 memory, Z_BUF_ERROR if there was not enough room in the output buffer,
|
|
|
1256 Z_STREAM_ERROR if the level parameter is invalid.
|
|
|
1257 */
|
|
|
1258
|
|
|
1259 size_t compressBound(size_t sourceLen);
|
|
|
1260 /*
|
|
|
1261 compressBound() returns an upper bound on the compressed size after
|
|
|
1262 compress() or compress2() on sourceLen bytes. It would be used before a
|
|
|
1263 compress() or compress2() call to allocate the destination buffer.
|
|
|
1264 */
|
|
|
1265
|
|
|
1266 int uncompress(ubyte* dest,
|
|
|
1267 size_t* destLen,
|
|
|
1268 const(ubyte)* source,
|
|
|
1269 size_t sourceLen);
|
|
|
1270 /*
|
|
|
1271 Decompresses the source buffer into the destination buffer. sourceLen is
|
|
|
1272 the byte length of the source buffer. Upon entry, destLen is the total size
|
|
|
1273 of the destination buffer, which must be large enough to hold the entire
|
|
|
1274 uncompressed data. (The size of the uncompressed data must have been saved
|
|
|
1275 previously by the compressor and transmitted to the decompressor by some
|
|
|
1276 mechanism outside the scope of this compression library.) Upon exit, destLen
|
|
|
1277 is the actual size of the uncompressed data.
|
|
|
1278
|
|
|
1279 uncompress returns Z_OK if success, Z_MEM_ERROR if there was not
|
|
|
1280 enough memory, Z_BUF_ERROR if there was not enough room in the output
|
|
|
1281 buffer, or Z_DATA_ERROR if the input data was corrupted or incomplete. In
|
|
|
1282 the case where there is not enough room, uncompress() will fill the output
|
|
|
1283 buffer with the uncompressed data up to that point.
|
|
|
1284 */
|
|
|
1285
|
|
|
1286 int uncompress2(ubyte* dest,
|
|
|
1287 size_t* destLen,
|
|
|
1288 const(ubyte)* source,
|
|
|
1289 size_t* sourceLen);
|
|
|
1290 /*
|
|
|
1291 Same as uncompress, except that sourceLen is a pointer, where the
|
|
|
1292 length of the source is *sourceLen. On return, *sourceLen is the number of
|
|
|
1293 source bytes consumed.
|
|
|
1294 */
|
|
|
1295
|
|
|
1296 /* gzip file access functions */
|
|
|
1297
|
|
|
1298 /*
|
|
|
1299 This library supports reading and writing files in gzip (.gz) format with
|
|
|
1300 an interface similar to that of stdio, using the functions that start with
|
|
|
1301 "gz". The gzip format is different from the zlib format. gzip is a gzip
|
|
|
1302 wrapper, documented in RFC 1952, wrapped around a deflate stream.
|
|
|
1303 */
|
|
|
1304
|
|
|
1305 alias gzFile = void*;
|
|
|
1306 alias z_off_t = int; // file offset
|
|
|
1307 alias z_size_t = size_t;
|
|
|
1308
|
|
|
1309 gzFile gzopen(const(char)* path, const(char)* mode);
|
|
|
1310 /*
|
|
|
1311 Opens a gzip (.gz) file for reading or writing. The mode parameter is as
|
|
|
1312 in fopen ("rb" or "wb") but can also include a compression level ("wb9") or
|
|
|
1313 a strategy: 'f' for filtered data as in "wb6f", 'h' for Huffman-only
|
|
|
1314 compression as in "wb1h", 'R' for run-length encoding as in "wb1R", or 'F'
|
|
|
1315 for fixed code compression as in "wb9F". (See the description of
|
|
|
1316 deflateInit2 for more information about the strategy parameter.) 'T' will
|
|
|
1317 request transparent writing or appending with no compression and not using
|
|
|
1318 the gzip format.
|
|
|
1319
|
|
|
1320 "a" can be used instead of "w" to request that the gzip stream that will
|
|
|
1321 be written be appended to the file. "+" will result in an error, since
|
|
|
1322 reading and writing to the same gzip file is not supported. The addition of
|
|
|
1323 "x" when writing will create the file exclusively, which fails if the file
|
|
|
1324 already exists. On systems that support it, the addition of "e" when
|
|
|
1325 reading or writing will set the flag to close the file on an execve() call.
|
|
|
1326
|
|
|
1327 These functions, as well as gzip, will read and decode a sequence of gzip
|
|
|
1328 streams in a file. The append function of gzopen() can be used to create
|
|
|
1329 such a file. (Also see gzflush() for another way to do this.) When
|
|
|
1330 appending, gzopen does not test whether the file begins with a gzip stream,
|
|
|
1331 nor does it look for the end of the gzip streams to begin appending. gzopen
|
|
|
1332 will simply append a gzip stream to the existing file.
|
|
|
1333
|
|
|
1334 gzopen can be used to read a file which is not in gzip format; in this
|
|
|
1335 case gzread will directly read from the file without decompression. When
|
|
|
1336 reading, this will be detected automatically by looking for the magic two-
|
|
|
1337 byte gzip header.
|
|
|
1338
|
|
|
1339 gzopen returns NULL if the file could not be opened, if there was
|
|
|
1340 insufficient memory to allocate the gzFile state, or if an invalid mode was
|
|
|
1341 specified (an 'r', 'w', or 'a' was not provided, or '+' was provided).
|
|
|
1342 errno can be checked to determine if the reason gzopen failed was that the
|
|
|
1343 file could not be opened.
|
|
|
1344 */
|
|
|
1345
|
|
|
1346 gzFile gzdopen(int fd, const(char)* mode);
|
|
|
1347 /*
|
|
|
1348 gzdopen associates a gzFile with the file descriptor fd. File descriptors
|
|
|
1349 are obtained from calls like open, dup, creat, pipe or fileno (if the file
|
|
|
1350 has been previously opened with fopen). The mode parameter is as in gzopen.
|
|
|
1351
|
|
|
1352 The next call of gzclose on the returned gzFile will also close the file
|
|
|
1353 descriptor fd, just like fclose(fdopen(fd, mode)) closes the file descriptor
|
|
|
1354 fd. If you want to keep fd open, use fd = dup(fd_keep); gz = gzdopen(fd,
|
|
|
1355 mode);. The duplicated descriptor should be saved to avoid a leak, since
|
|
|
1356 gzdopen does not close fd if it fails. If you are using fileno() to get the
|
|
|
1357 file descriptor from a FILE *, then you will have to use dup() to avoid
|
|
|
1358 double-close()ing the file descriptor. Both gzclose() and fclose() will
|
|
|
1359 close the associated file descriptor, so they need to have different file
|
|
|
1360 descriptors.
|
|
|
1361
|
|
|
1362 gzdopen returns NULL if there was insufficient memory to allocate the
|
|
|
1363 gzFile state, if an invalid mode was specified (an 'r', 'w', or 'a' was not
|
|
|
1364 provided, or '+' was provided), or if fd is -1. The file descriptor is not
|
|
|
1365 used until the next gz* read, write, seek, or close operation, so gzdopen
|
|
|
1366 will not detect if fd is invalid (unless fd is -1).
|
|
|
1367 */
|
|
|
1368
|
|
|
1369 int gzbuffer(gzFile file, uint size);
|
|
|
1370 /*
|
|
|
1371 Set the internal buffer size used by this library's functions. The
|
|
|
1372 default buffer size is 8192 bytes. This function must be called after
|
|
|
1373 gzopen() or gzdopen(), and before any other calls that read or write the
|
|
|
1374 file. The buffer memory allocation is always deferred to the first read or
|
|
|
1375 write. Three times that size in buffer space is allocated. A larger buffer
|
|
|
1376 size of, for example, 64K or 128K bytes will noticeably increase the speed
|
|
|
1377 of decompression (reading).
|
|
|
1378
|
|
|
1379 The new buffer size also affects the maximum length for gzprintf().
|
|
|
1380
|
|
|
1381 gzbuffer() returns 0 on success, or -1 on failure, such as being called
|
|
|
1382 too late.
|
|
|
1383 */
|
|
|
1384
|
|
|
1385 int gzsetparams(gzFile file, int level, int strategy);
|
|
|
1386 /*
|
|
|
1387 Dynamically update the compression level or strategy. See the description
|
|
|
1388 of deflateInit2 for the meaning of these parameters. Previously provided
|
|
|
1389 data is flushed before the parameter change.
|
|
|
1390
|
|
|
1391 gzsetparams returns Z_OK if success, Z_STREAM_ERROR if the file was not
|
|
|
1392 opened for writing, Z_ERRNO if there is an error writing the flushed data,
|
|
|
1393 or Z_MEM_ERROR if there is a memory allocation error.
|
|
|
1394 */
|
|
|
1395
|
|
|
1396 int gzread(gzFile file, void* buf, uint len);
|
|
|
1397 /*
|
|
|
1398 Reads the given number of uncompressed bytes from the compressed file. If
|
|
|
1399 the input file is not in gzip format, gzread copies the given number of
|
|
|
1400 bytes into the buffer directly from the file.
|
|
|
1401
|
|
|
1402 After reaching the end of a gzip stream in the input, gzread will continue
|
|
|
1403 to read, looking for another gzip stream. Any number of gzip streams may be
|
|
|
1404 concatenated in the input file, and will all be decompressed by gzread().
|
|
|
1405 If something other than a gzip stream is encountered after a gzip stream,
|
|
|
1406 that remaining trailing garbage is ignored (and no error is returned).
|
|
|
1407
|
|
|
1408 gzread can be used to read a gzip file that is being concurrently written.
|
|
|
1409 Upon reaching the end of the input, gzread will return with the available
|
|
|
1410 data. If the error code returned by gzerror is Z_OK or Z_BUF_ERROR, then
|
|
|
1411 gzclearerr can be used to clear the end of file indicator in order to permit
|
|
|
1412 gzread to be tried again. Z_OK indicates that a gzip stream was completed
|
|
|
1413 on the last gzread. Z_BUF_ERROR indicates that the input file ended in the
|
|
|
1414 middle of a gzip stream. Note that gzread does not return -1 in the event
|
|
|
1415 of an incomplete gzip stream. This error is deferred until gzclose(), which
|
|
|
1416 will return Z_BUF_ERROR if the last gzread ended in the middle of a gzip
|
|
|
1417 stream. Alternatively, gzerror can be used before gzclose to detect this
|
|
|
1418 case.
|
|
|
1419
|
|
|
1420 gzread returns the number of uncompressed bytes actually read, less than
|
|
|
1421 len for end of file, or -1 for error. If len is too large to fit in an int,
|
|
|
1422 then nothing is read, -1 is returned, and the error state is set to
|
|
|
1423 Z_STREAM_ERROR.
|
|
|
1424 */
|
|
|
1425
|
|
|
1426 z_size_t gzfread(void* buf, z_size_t size, z_size_t nitems, gzFile file);
|
|
|
1427 /*
|
|
|
1428 Read up to nitems items of size size from file to buf, otherwise operating
|
|
|
1429 as gzread() does. This duplicates the interface of stdio's fread(), with
|
|
|
1430 size_t request and return types. If the library defines size_t, then
|
|
|
1431 z_size_t is identical to size_t. If not, then z_size_t is an unsigned
|
|
|
1432 integer type that can contain a pointer.
|
|
|
1433
|
|
|
1434 gzfread() returns the number of full items read of size size, or zero if
|
|
|
1435 the end of the file was reached and a full item could not be read, or if
|
|
|
1436 there was an error. gzerror() must be consulted if zero is returned in
|
|
|
1437 order to determine if there was an error. If the multiplication of size and
|
|
|
1438 nitems overflows, i.e. the product does not fit in a z_size_t, then nothing
|
|
|
1439 is read, zero is returned, and the error state is set to Z_STREAM_ERROR.
|
|
|
1440
|
|
|
1441 In the event that the end of file is reached and only a partial item is
|
|
|
1442 available at the end, i.e. the remaining uncompressed data length is not a
|
|
|
1443 multiple of size, then the final partial item is nevetheless read into buf
|
|
|
1444 and the end-of-file flag is set. The length of the partial item read is not
|
|
|
1445 provided, but could be inferred from the result of gztell(). This behavior
|
|
|
1446 is the same as the behavior of fread() implementations in common libraries,
|
|
|
1447 but it prevents the direct use of gzfread() to read a concurrently written
|
|
|
1448 file, reseting and retrying on end-of-file, when size is not 1.
|
|
|
1449 */
|
|
|
1450
|
|
|
1451 int gzwrite(gzFile file, void* buf, uint len);
|
|
|
1452 /*
|
|
|
1453 Writes the given number of uncompressed bytes into the compressed file.
|
|
|
1454 gzwrite returns the number of uncompressed bytes written or 0 in case of
|
|
|
1455 error.
|
|
|
1456 */
|
|
|
1457
|
|
|
1458 z_size_t gzfwrite(void* buf, z_size_t size, z_size_t nitems, gzFile file);
|
|
|
1459 /*
|
|
|
1460 gzfwrite() writes nitems items of size size from buf to file, duplicating
|
|
|
1461 the interface of stdio's fwrite(), with size_t request and return types. If
|
|
|
1462 the library defines size_t, then z_size_t is identical to size_t. If not,
|
|
|
1463 then z_size_t is an unsigned integer type that can contain a pointer.
|
|
|
1464
|
|
|
1465 gzfwrite() returns the number of full items written of size size, or zero
|
|
|
1466 if there was an error. If the multiplication of size and nitems overflows,
|
|
|
1467 i.e. the product does not fit in a z_size_t, then nothing is written, zero
|
|
|
1468 is returned, and the error state is set to Z_STREAM_ERROR.
|
|
|
1469 */
|
|
|
1470
|
|
|
1471 int gzprintf(gzFile file, const(char)* format, ...);
|
|
|
1472 /*
|
|
|
1473 Converts, formats, and writes the arguments to the compressed file under
|
|
|
1474 control of the format string, as in fprintf. gzprintf returns the number of
|
|
|
1475 uncompressed bytes actually written, or a negative zlib error code in case
|
|
|
1476 of error. The number of uncompressed bytes written is limited to 8191, or
|
|
|
1477 one less than the buffer size given to gzbuffer(). The caller should assure
|
|
|
1478 that this limit is not exceeded. If it is exceeded, then gzprintf() will
|
|
|
1479 return an error (0) with nothing written. In this case, there may also be a
|
|
|
1480 buffer overflow with unpredictable consequences, which is possible only if
|
|
|
1481 zlib was compiled with the insecure functions sprintf() or vsprintf()
|
|
|
1482 because the secure snprintf() or vsnprintf() functions were not available.
|
|
|
1483 This can be determined using zlibCompileFlags().
|
|
|
1484 */
|
|
|
1485
|
|
|
1486 int gzputs(gzFile file, const(char)* s);
|
|
|
1487 /*
|
|
|
1488 Writes the given null-terminated string to the compressed file, excluding
|
|
|
1489 the terminating null character.
|
|
|
1490
|
|
|
1491 gzputs returns the number of characters written, or -1 in case of error.
|
|
|
1492 */
|
|
|
1493
|
|
|
1494 const(char)* gzgets(gzFile file, const(char)* buf, int len);
|
|
|
1495 /*
|
|
|
1496 Reads bytes from the compressed file until len-1 characters are read, or a
|
|
|
1497 newline character is read and transferred to buf, or an end-of-file
|
|
|
1498 condition is encountered. If any characters are read or if len == 1, the
|
|
|
1499 string is terminated with a null character. If no characters are read due
|
|
|
1500 to an end-of-file or len < 1, then the buffer is left untouched.
|
|
|
1501
|
|
|
1502 gzgets returns buf which is a null-terminated string, or it returns NULL
|
|
|
1503 for end-of-file or in case of error. If there was an error, the contents at
|
|
|
1504 buf are indeterminate.
|
|
|
1505 */
|
|
|
1506
|
|
|
1507 int gzputc(gzFile file, int c);
|
|
|
1508 /*
|
|
|
1509 Writes c, converted to an unsigned char, into the compressed file. gzputc
|
|
|
1510 returns the value that was written, or -1 in case of error.
|
|
|
1511 */
|
|
|
1512
|
|
|
1513 int gzgetc(gzFile file);
|
|
|
1514 /*
|
|
|
1515 Reads one byte from the compressed file. gzgetc returns this byte or -1
|
|
|
1516 in case of end of file or error. This is implemented as a macro for speed.
|
|
|
1517 As such, it does not do all of the checking the other functions do. I.e.
|
|
|
1518 it does not check to see if file is NULL, nor whether the structure file
|
|
|
1519 points to has been clobbered or not.
|
|
|
1520 */
|
|
|
1521
|
|
|
1522 int gzungetc(int c, gzFile file);
|
|
|
1523 /*
|
|
|
1524 Push one character back onto the stream to be read as the first character
|
|
|
1525 on the next read. At least one character of push-back is allowed.
|
|
|
1526 gzungetc() returns the character pushed, or -1 on failure. gzungetc() will
|
|
|
1527 fail if c is -1, and may fail if a character has been pushed but not read
|
|
|
1528 yet. If gzungetc is used immediately after gzopen or gzdopen, at least the
|
|
|
1529 output buffer size of pushed characters is allowed. (See gzbuffer above.)
|
|
|
1530 The pushed character will be discarded if the stream is repositioned with
|
|
|
1531 gzseek() or gzrewind().
|
|
|
1532 */
|
|
|
1533
|
|
|
1534 int gzflush(gzFile file, int flush);
|
|
|
1535 /*
|
|
|
1536 Flushes all pending output into the compressed file. The parameter flush
|
|
|
1537 is as in the deflate() function. The return value is the zlib error number
|
|
|
1538 (see function gzerror below). gzflush is only permitted when writing.
|
|
|
1539
|
|
|
1540 If the flush parameter is Z_FINISH, the remaining data is written and the
|
|
|
1541 gzip stream is completed in the output. If gzwrite() is called again, a new
|
|
|
1542 gzip stream will be started in the output. gzread() is able to read such
|
|
|
1543 concatenated gzip streams.
|
|
|
1544
|
|
|
1545 gzflush should be called only when strictly necessary because it will
|
|
|
1546 degrade compression if called too often.
|
|
|
1547 */
|
|
|
1548
|
|
|
1549 z_off_t gzseek(gzFile file, z_off_t offset, int whence);
|
|
|
1550 /*
|
|
|
1551 Sets the starting position for the next gzread or gzwrite on the given
|
|
|
1552 compressed file. The offset represents a number of bytes in the
|
|
|
1553 uncompressed data stream. The whence parameter is defined as in lseek(2);
|
|
|
1554 the value SEEK_END is not supported.
|
|
|
1555
|
|
|
1556 If the file is opened for reading, this function is emulated but can be
|
|
|
1557 extremely slow. If the file is opened for writing, only forward seeks are
|
|
|
1558 supported; gzseek then compresses a sequence of zeroes up to the new
|
|
|
1559 starting position.
|
|
|
1560
|
|
|
1561 gzseek returns the resulting offset location as measured in bytes from
|
|
|
1562 the beginning of the uncompressed stream, or -1 in case of error, in
|
|
|
1563 particular if the file is opened for writing and the new starting position
|
|
|
1564 would be before the current position.
|
|
|
1565 */
|
|
|
1566
|
|
|
1567 int gzrewind(gzFile file);
|
|
|
1568 /*
|
|
|
1569 Rewinds the given file. This function is supported only for reading.
|
|
|
1570
|
|
|
1571 gzrewind(file) is equivalent to (int)gzseek(file, 0L, SEEK_SET)
|
|
|
1572 */
|
|
|
1573
|
|
|
1574 z_off_t gztell(gzFile file);
|
|
|
1575 /*
|
|
|
1576 Returns the starting position for the next gzread or gzwrite on the given
|
|
|
1577 compressed file. This position represents a number of bytes in the
|
|
|
1578 uncompressed data stream, and is zero when starting, even if appending or
|
|
|
1579 reading a gzip stream from the middle of a file using gzdopen().
|
|
|
1580
|
|
|
1581 gztell(file) is equivalent to gzseek(file, 0L, SEEK_CUR)
|
|
|
1582 */
|
|
|
1583
|
|
|
1584 z_off_t gzoffset(gzFile file);
|
|
|
1585 /*
|
|
|
1586 Returns the current offset in the file being read or written. This offset
|
|
|
1587 includes the count of bytes that precede the gzip stream, for example when
|
|
|
1588 appending or when using gzdopen() for reading. When reading, the offset
|
|
|
1589 does not include as yet unused buffered input. This information can be used
|
|
|
1590 for a progress indicator. On error, gzoffset() returns -1.
|
|
|
1591 */
|
|
|
1592
|
|
|
1593 int gzeof(gzFile file);
|
|
|
1594 /*
|
|
|
1595 Returns true (1) if the end-of-file indicator has been set while reading,
|
|
|
1596 false (0) otherwise. Note that the end-of-file indicator is set only if the
|
|
|
1597 read tried to go past the end of the input, but came up short. Therefore,
|
|
|
1598 just like feof(), gzeof() may return false even if there is no more data to
|
|
|
1599 read, in the event that the last read request was for the exact number of
|
|
|
1600 bytes remaining in the input file. This will happen if the input file size
|
|
|
1601 is an exact multiple of the buffer size.
|
|
|
1602
|
|
|
1603 If gzeof() returns true, then the read functions will return no more data,
|
|
|
1604 unless the end-of-file indicator is reset by gzclearerr() and the input file
|
|
|
1605 has grown since the previous end of file was detected.
|
|
|
1606 */
|
|
|
1607
|
|
|
1608 int gzdirect(gzFile file);
|
|
|
1609 /*
|
|
|
1610 Returns true (1) if file is being copied directly while reading, or false
|
|
|
1611 (0) if file is a gzip stream being decompressed.
|
|
|
1612
|
|
|
1613 If the input file is empty, gzdirect() will return true, since the input
|
|
|
1614 does not contain a gzip stream.
|
|
|
1615
|
|
|
1616 If gzdirect() is used immediately after gzopen() or gzdopen() it will
|
|
|
1617 cause buffers to be allocated to allow reading the file to determine if it
|
|
|
1618 is a gzip file. Therefore if gzbuffer() is used, it should be called before
|
|
|
1619 gzdirect().
|
|
|
1620
|
|
|
1621 When writing, gzdirect() returns true (1) if transparent writing was
|
|
|
1622 requested ("wT" for the gzopen() mode), or false (0) otherwise. (Note:
|
|
|
1623 gzdirect() is not needed when writing. Transparent writing must be
|
|
|
1624 explicitly requested, so the application already knows the answer. When
|
|
|
1625 linking statically, using gzdirect() will include all of the zlib code for
|
|
|
1626 gzip file reading and decompression, which may not be desired.)
|
|
|
1627 */
|
|
|
1628
|
|
|
1629 int gzclose(gzFile file);
|
|
|
1630 /*
|
|
|
1631 Flushes all pending output if necessary, closes the compressed file and
|
|
|
1632 deallocates the (de)compression state. Note that once file is closed, you
|
|
|
1633 cannot call gzerror with file, since its structures have been deallocated.
|
|
|
1634 gzclose must not be called more than once on the same file, just as free
|
|
|
1635 must not be called more than once on the same allocation.
|
|
|
1636
|
|
|
1637 gzclose will return Z_STREAM_ERROR if file is not valid, Z_ERRNO on a
|
|
|
1638 file operation error, Z_MEM_ERROR if out of memory, Z_BUF_ERROR if the
|
|
|
1639 last read ended in the middle of a gzip stream, or Z_OK on success.
|
|
|
1640 */
|
|
|
1641
|
|
|
1642 int gzclose_r(gzFile file);
|
|
|
1643 int gzclose_w(gzFile file);
|
|
|
1644 /*
|
|
|
1645 Same as gzclose(), but gzclose_r() is only for use when reading, and
|
|
|
1646 gzclose_w() is only for use when writing or appending. The advantage to
|
|
|
1647 using these instead of gzclose() is that they avoid linking in zlib
|
|
|
1648 compression or decompression code that is not used when only reading or only
|
|
|
1649 writing respectively. If gzclose() is used, then both compression and
|
|
|
1650 decompression code will be included the application when linking to a static
|
|
|
1651 zlib library.
|
|
|
1652 */
|
|
|
1653
|
|
|
1654 const(char)* gzerror(gzFile file, int* errnum);
|
|
|
1655 /*
|
|
|
1656 Returns the error message for the last error which occurred on the given
|
|
|
1657 compressed file. errnum is set to zlib error number. If an error occurred
|
|
|
1658 in the file system and not in the compression library, errnum is set to
|
|
|
1659 Z_ERRNO and the application may consult errno to get the exact error code.
|
|
|
1660
|
|
|
1661 The application must not modify the returned string. Future calls to
|
|
|
1662 this function may invalidate the previously returned string. If file is
|
|
|
1663 closed, then the string previously returned by gzerror will no longer be
|
|
|
1664 available.
|
|
|
1665
|
|
|
1666 gzerror() should be used to distinguish errors from end-of-file for those
|
|
|
1667 functions above that do not distinguish those cases in their return values.
|
|
|
1668 */
|
|
|
1669
|
|
|
1670 void gzclearerr(gzFile file);
|
|
|
1671 /*
|
|
|
1672 Clears the error and end-of-file flags for file. This is analogous to the
|
|
|
1673 clearerr() function in stdio. This is useful for continuing to read a gzip
|
|
|
1674 file that is being written concurrently.
|
|
|
1675 */
|
|
|
1676
|
|
|
1677 /* checksum functions */
|
|
|
1678
|
|
|
1679 /*
|
|
|
1680 These functions are not related to compression but are exported
|
|
|
1681 anyway because they might be useful in applications using the compression
|
|
|
1682 library.
|
|
|
1683 */
|
|
|
1684
|
|
|
1685 uint adler32(uint adler, const(ubyte)* buf, uint len);
|
|
|
1686 /*
|
|
|
1687 Update a running Adler-32 checksum with the bytes buf[0 .. len-1] and
|
|
|
1688 return the updated checksum. If buf is Z_NULL, this function returns the
|
|
|
1689 required initial value for the checksum.
|
|
|
1690
|
|
|
1691 An Adler-32 checksum is almost as reliable as a CRC-32 but can be computed
|
|
|
1692 much faster.
|
|
|
1693
|
|
|
1694 Usage example:
|
|
|
1695
|
|
|
1696 uLong adler = adler32(0L, Z_NULL, 0);
|
|
|
1697
|
|
|
1698 while (read_buffer(buffer, length) != EOF)
|
|
|
1699 adler = adler32(adler, buffer, length);
|
|
|
1700
|
|
|
1701 if (adler != original_adler) error();
|
|
|
1702 */
|
|
|
1703
|
|
|
1704 uint adler32_z (uint adler, const(ubyte)* buf, z_size_t len);
|
|
|
1705 /*
|
|
|
1706 Same as adler32(), but with a size_t length.
|
|
|
1707 */
|
|
|
1708
|
|
|
1709 uint adler32_combine(uint adler1, uint adler2, z_off_t len2);
|
|
|
1710 /*
|
|
|
1711 Combine two Adler-32 checksums into one. For two sequences of bytes, seq1
|
|
|
1712 and seq2 with lengths len1 and len2, Adler-32 checksums were calculated for
|
|
|
1713 each, adler1 and adler2. adler32_combine() returns the Adler-32 checksum of
|
|
|
1714 seq1 and seq2 concatenated, requiring only adler1, adler2, and len2. Note
|
|
|
1715 that the z_off_t type (like off_t) is a signed integer. If len2 is
|
|
|
1716 negative, the result has no meaning or utility.
|
|
|
1717 */
|
|
|
1718
|
|
|
1719 uint crc32(uint crc, const(ubyte)* buf, uint len);
|
|
|
1720 /*
|
|
|
1721 Update a running CRC-32 with the bytes buf[0 .. len-1] and return the
|
|
|
1722 updated CRC-32. If buf is Z_NULL, this function returns the required
|
|
|
1723 initial value for the crc. Pre- and post-conditioning (one's complement) is
|
|
|
1724 performed within this function so it shouldn't be done by the application.
|
|
|
1725
|
|
|
1726 Usage example:
|
|
|
1727
|
|
|
1728 uLong crc = crc32(0L, Z_NULL, 0);
|
|
|
1729
|
|
|
1730 while (read_buffer(buffer, length) != EOF)
|
|
|
1731 crc = crc32(crc, buffer, length);
|
|
|
1732
|
|
|
1733 if (crc != original_crc) error();
|
|
|
1734 */
|
|
|
1735
|
|
|
1736 uint crc32_z(uint adler, const(ubyte)* buf, z_size_t len);
|
|
|
1737 /*
|
|
|
1738 Same as crc32(), but with a size_t length.
|
|
|
1739 */
|
|
|
1740
|
|
|
1741 uint crc32_combine(uint crc1, uint crc2, z_off_t len2);
|
|
|
1742
|
|
|
1743 /*
|
|
|
1744 Combine two CRC-32 check values into one. For two sequences of bytes,
|
|
|
1745 seq1 and seq2 with lengths len1 and len2, CRC-32 check values were
|
|
|
1746 calculated for each, crc1 and crc2. crc32_combine() returns the CRC-32
|
|
|
1747 check value of seq1 and seq2 concatenated, requiring only crc1, crc2, and
|
|
|
1748 len2.
|
|
|
1749 */
|
|
|
1750
|
|
|
1751
|
|
|
1752 /* various hacks, don't look :) */
|
|
|
1753
|
|
|
1754 /* deflateInit and inflateInit are macros to allow checking the zlib version
|
|
|
1755 * and the compiler's view of z_stream:
|
|
|
1756 */
|
|
|
1757 int deflateInit_(z_streamp strm,
|
|
|
1758 int level,
|
|
|
1759 const(char)* versionx,
|
|
|
1760 int stream_size);
|
|
|
1761
|
|
|
1762 int inflateInit_(z_streamp strm,
|
|
|
1763 const(char)* versionx,
|
|
|
1764 int stream_size);
|
|
|
1765
|
|
|
1766 int deflateInit2_(z_streamp strm,
|
|
|
1767 int level,
|
|
|
1768 int method,
|
|
|
1769 int windowBits,
|
|
|
1770 int memLevel,
|
|
|
1771 int strategy,
|
|
|
1772 const(char)* versionx,
|
|
|
1773 int stream_size);
|
|
|
1774
|
|
|
1775 int inflateBackInit_(z_stream* strm,
|
|
|
1776 int windowBits,
|
|
|
1777 ubyte* window,
|
|
|
1778 const(char)* z_version,
|
|
|
1779 int stream_size);
|
|
|
1780
|
|
|
1781 int inflateInit2_(z_streamp strm,
|
|
|
1782 int windowBits,
|
|
|
1783 const(char)* versionx,
|
|
|
1784 int stream_size);
|
|
|
1785
|
|
|
1786 const(char)* zError(int err);
|
|
|
1787 int inflateSyncPoint(z_streamp z);
|
|
|
1788 const(uint)* get_crc_table();
|
