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1 /* zlib.h -- interface of the 'zlib' general purpose compression library
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2 version 1.2.3, July 18th, 2005
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3
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4 Copyright (C) 1995-2005 Jean-loup Gailly and Mark Adler
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5
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6 This software is provided 'as-is', without any express or implied
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7 warranty. In no event will the authors be held liable for any damages
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8 arising from the use of this software.
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9
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10 Permission is granted to anyone to use this software for any purpose,
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11 including commercial applications, and to alter it and redistribute it
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12 freely, subject to the following restrictions:
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13
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14 1. The origin of this software must not be misrepresented; you must not
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15 claim that you wrote the original software. If you use this software
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16 in a product, an acknowledgment in the product documentation would be
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17 appreciated but is not required.
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18 2. Altered source versions must be plainly marked as such, and must not be
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19 misrepresented as being the original software.
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20 3. This notice may not be removed or altered from any source distribution.
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21
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22 Jean-loup Gailly Mark Adler
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23 jloup@gzip.org madler@alumni.caltech.edu
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24
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25
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26 The data format used by the zlib library is described by RFCs (Request for
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27 Comments) 1950 to 1952 in the files http://www.ietf.org/rfc/rfc1950.txt
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28 (zlib format), rfc1951.txt (deflate format) and rfc1952.txt (gzip format).
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29 */
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30
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31 #ifndef ZLIB_H
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32 #define ZLIB_H
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33
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34 #include "zconf.h"
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35
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36 #ifdef __cplusplus
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37 extern "C" {
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38 #endif
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39
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40 #define ZLIB_VERSION "1.2.3"
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41 #define ZLIB_VERNUM 0x1230
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42
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43 /*
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44 The 'zlib' compression library provides in-memory compression and
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45 decompression functions, including integrity checks of the uncompressed
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46 data. This version of the library supports only one compression method
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47 (deflation) but other algorithms will be added later and will have the same
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48 stream interface.
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49
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50 Compression can be done in a single step if the buffers are large
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51 enough (for example if an input file is mmap'ed), or can be done by
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52 repeated calls of the compression function. In the latter case, the
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53 application must provide more input and/or consume the output
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54 (providing more output space) before each call.
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55
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56 The compressed data format used by default by the in-memory functions is
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57 the zlib format, which is a zlib wrapper documented in RFC 1950, wrapped
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58 around a deflate stream, which is itself documented in RFC 1951.
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59
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60 The library also supports reading and writing files in gzip (.gz) format
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61 with an interface similar to that of stdio using the functions that start
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62 with "gz". The gzip format is different from the zlib format. gzip is a
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63 gzip wrapper, documented in RFC 1952, wrapped around a deflate stream.
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64
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65 This library can optionally read and write gzip streams in memory as well.
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66
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67 The zlib format was designed to be compact and fast for use in memory
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68 and on communications channels. The gzip format was designed for single-
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69 file compression on file systems, has a larger header than zlib to maintain
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70 directory information, and uses a different, slower check method than zlib.
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71
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72 The library does not install any signal handler. The decoder checks
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73 the consistency of the compressed data, so the library should never
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74 crash even in case of corrupted input.
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75 */
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76
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77 typedef voidpf (*alloc_func) OF((voidpf opaque, uInt items, uInt size));
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78 typedef void (*free_func) OF((voidpf opaque, voidpf address));
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79
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80 struct internal_state;
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81
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82 typedef struct z_stream_s {
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83 Bytef *next_in; /* next input byte */
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84 uInt avail_in; /* number of bytes available at next_in */
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85 uLong total_in; /* total nb of input bytes read so far */
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86
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87 Bytef *next_out; /* next output byte should be put there */
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88 uInt avail_out; /* remaining free space at next_out */
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89 uLong total_out; /* total nb of bytes output so far */
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90
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91 char *msg; /* last error message, NULL if no error */
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92 struct internal_state FAR *state; /* not visible by applications */
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93
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94 alloc_func zalloc; /* used to allocate the internal state */
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95 free_func zfree; /* used to free the internal state */
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96 voidpf opaque; /* private data object passed to zalloc and zfree */
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97
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98 int data_type; /* best guess about the data type: binary or text */
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99 uLong adler; /* adler32 value of the uncompressed data */
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100 uLong reserved; /* reserved for future use */
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101 } z_stream;
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102
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103 typedef z_stream FAR *z_streamp;
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104
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105 /*
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106 gzip header information passed to and from zlib routines. See RFC 1952
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107 for more details on the meanings of these fields.
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108 */
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109 typedef struct gz_header_s {
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110 int text; /* true if compressed data believed to be text */
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111 uLong time; /* modification time */
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112 int xflags; /* extra flags (not used when writing a gzip file) */
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113 int os; /* operating system */
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114 Bytef *extra; /* pointer to extra field or Z_NULL if none */
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115 uInt extra_len; /* extra field length (valid if extra != Z_NULL) */
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116 uInt extra_max; /* space at extra (only when reading header) */
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117 Bytef *name; /* pointer to zero-terminated file name or Z_NULL */
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118 uInt name_max; /* space at name (only when reading header) */
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119 Bytef *comment; /* pointer to zero-terminated comment or Z_NULL */
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120 uInt comm_max; /* space at comment (only when reading header) */
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121 int hcrc; /* true if there was or will be a header crc */
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122 int done; /* true when done reading gzip header (not used
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123 when writing a gzip file) */
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124 } gz_header;
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125
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126 typedef gz_header FAR *gz_headerp;
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127
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128 /*
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129 The application must update next_in and avail_in when avail_in has
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130 dropped to zero. It must update next_out and avail_out when avail_out
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131 has dropped to zero. The application must initialize zalloc, zfree and
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132 opaque before calling the init function. All other fields are set by the
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133 compression library and must not be updated by the application.
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134
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135 The opaque value provided by the application will be passed as the first
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136 parameter for calls of zalloc and zfree. This can be useful for custom
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137 memory management. The compression library attaches no meaning to the
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138 opaque value.
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139
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140 zalloc must return Z_NULL if there is not enough memory for the object.
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141 If zlib is used in a multi-threaded application, zalloc and zfree must be
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142 thread safe.
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143
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144 On 16-bit systems, the functions zalloc and zfree must be able to allocate
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145 exactly 65536 bytes, but will not be required to allocate more than this
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146 if the symbol MAXSEG_64K is defined (see zconf.h). WARNING: On MSDOS,
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147 pointers returned by zalloc for objects of exactly 65536 bytes *must*
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148 have their offset normalized to zero. The default allocation function
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149 provided by this library ensures this (see zutil.c). To reduce memory
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150 requirements and avoid any allocation of 64K objects, at the expense of
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151 compression ratio, compile the library with -DMAX_WBITS=14 (see zconf.h).
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152
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153 The fields total_in and total_out can be used for statistics or
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154 progress reports. After compression, total_in holds the total size of
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155 the uncompressed data and may be saved for use in the decompressor
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156 (particularly if the decompressor wants to decompress everything in
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157 a single step).
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158 */
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159
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160 /* constants */
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161
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162 #define Z_NO_FLUSH 0
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163 #define Z_PARTIAL_FLUSH 1 /* will be removed, use Z_SYNC_FLUSH instead */
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164 #define Z_SYNC_FLUSH 2
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165 #define Z_FULL_FLUSH 3
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166 #define Z_FINISH 4
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167 #define Z_BLOCK 5
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168 /* Allowed flush values; see deflate() and inflate() below for details */
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169
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170 #define Z_OK 0
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171 #define Z_STREAM_END 1
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172 #define Z_NEED_DICT 2
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173 #define Z_ERRNO (-1)
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174 #define Z_STREAM_ERROR (-2)
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175 #define Z_DATA_ERROR (-3)
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176 #define Z_MEM_ERROR (-4)
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177 #define Z_BUF_ERROR (-5)
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178 #define Z_VERSION_ERROR (-6)
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179 /* Return codes for the compression/decompression functions. Negative
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180 * values are errors, positive values are used for special but normal events.
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181 */
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182
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183 #define Z_NO_COMPRESSION 0
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184 #define Z_BEST_SPEED 1
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185 #define Z_BEST_COMPRESSION 9
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186 #define Z_DEFAULT_COMPRESSION (-1)
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187 /* compression levels */
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188
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189 #define Z_FILTERED 1
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190 #define Z_HUFFMAN_ONLY 2
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191 #define Z_RLE 3
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192 #define Z_FIXED 4
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193 #define Z_DEFAULT_STRATEGY 0
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194 /* compression strategy; see deflateInit2() below for details */
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195
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196 #define Z_BINARY 0
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197 #define Z_TEXT 1
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198 #define Z_ASCII Z_TEXT /* for compatibility with 1.2.2 and earlier */
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199 #define Z_UNKNOWN 2
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200 /* Possible values of the data_type field (though see inflate()) */
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201
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202 #define Z_DEFLATED 8
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203 /* The deflate compression method (the only one supported in this version) */
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204
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205 #define Z_NULL 0 /* for initializing zalloc, zfree, opaque */
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206
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207 #define zlib_version zlibVersion()
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208 /* for compatibility with versions < 1.0.2 */
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209
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210 /* basic functions */
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211
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212 ZEXTERN const char * ZEXPORT zlibVersion OF((void));
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213 /* The application can compare zlibVersion and ZLIB_VERSION for consistency.
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214 If the first character differs, the library code actually used is
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215 not compatible with the zlib.h header file used by the application.
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216 This check is automatically made by deflateInit and inflateInit.
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217 */
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218
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219 /*
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220 ZEXTERN int ZEXPORT deflateInit OF((z_streamp strm, int level));
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221
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222 Initializes the internal stream state for compression. The fields
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223 zalloc, zfree and opaque must be initialized before by the caller.
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224 If zalloc and zfree are set to Z_NULL, deflateInit updates them to
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225 use default allocation functions.
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226
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227 The compression level must be Z_DEFAULT_COMPRESSION, or between 0 and 9:
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228 1 gives best speed, 9 gives best compression, 0 gives no compression at
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229 all (the input data is simply copied a block at a time).
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230 Z_DEFAULT_COMPRESSION requests a default compromise between speed and
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231 compression (currently equivalent to level 6).
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232
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233 deflateInit returns Z_OK if success, Z_MEM_ERROR if there was not
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234 enough memory, Z_STREAM_ERROR if level is not a valid compression level,
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235 Z_VERSION_ERROR if the zlib library version (zlib_version) is incompatible
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236 with the version assumed by the caller (ZLIB_VERSION).
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237 msg is set to null if there is no error message. deflateInit does not
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238 perform any compression: this will be done by deflate().
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239 */
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240
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241
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242 ZEXTERN int ZEXPORT deflate OF((z_streamp strm, int flush));
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243 /*
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244 deflate compresses as much data as possible, and stops when the input
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245 buffer becomes empty or the output buffer becomes full. It may introduce some
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246 output latency (reading input without producing any output) except when
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247 forced to flush.
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248
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249 The detailed semantics are as follows. deflate performs one or both of the
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250 following actions:
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251
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252 - Compress more input starting at next_in and update next_in and avail_in
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253 accordingly. If not all input can be processed (because there is not
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254 enough room in the output buffer), next_in and avail_in are updated and
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255 processing will resume at this point for the next call of deflate().
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256
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257 - Provide more output starting at next_out and update next_out and avail_out
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258 accordingly. This action is forced if the parameter flush is non zero.
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259 Forcing flush frequently degrades the compression ratio, so this parameter
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260 should be set only when necessary (in interactive applications).
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261 Some output may be provided even if flush is not set.
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262
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263 Before the call of deflate(), the application should ensure that at least
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264 one of the actions is possible, by providing more input and/or consuming
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265 more output, and updating avail_in or avail_out accordingly; avail_out
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266 should never be zero before the call. The application can consume the
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267 compressed output when it wants, for example when the output buffer is full
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268 (avail_out == 0), or after each call of deflate(). If deflate returns Z_OK
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269 and with zero avail_out, it must be called again after making room in the
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270 output buffer because there might be more output pending.
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271
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272 Normally the parameter flush is set to Z_NO_FLUSH, which allows deflate to
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273 decide how much data to accumualte before producing output, in order to
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274 maximize compression.
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275
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276 If the parameter flush is set to Z_SYNC_FLUSH, all pending output is
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277 flushed to the output buffer and the output is aligned on a byte boundary, so
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278 that the decompressor can get all input data available so far. (In particular
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279 avail_in is zero after the call if enough output space has been provided
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280 before the call.) Flushing may degrade compression for some compression
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281 algorithms and so it should be used only when necessary.
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282
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283 If flush is set to Z_FULL_FLUSH, all output is flushed as with
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284 Z_SYNC_FLUSH, and the compression state is reset so that decompression can
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285 restart from this point if previous compressed data has been damaged or if
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286 random access is desired. Using Z_FULL_FLUSH too often can seriously degrade
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287 compression.
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288
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289 If deflate returns with avail_out == 0, this function must be called again
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290 with the same value of the flush parameter and more output space (updated
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291 avail_out), until the flush is complete (deflate returns with non-zero
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292 avail_out). In the case of a Z_FULL_FLUSH or Z_SYNC_FLUSH, make sure that
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293 avail_out is greater than six to avoid repeated flush markers due to
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294 avail_out == 0 on return.
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295
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296 If the parameter flush is set to Z_FINISH, pending input is processed,
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297 pending output is flushed and deflate returns with Z_STREAM_END if there
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298 was enough output space; if deflate returns with Z_OK, this function must be
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299 called again with Z_FINISH and more output space (updated avail_out) but no
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300 more input data, until it returns with Z_STREAM_END or an error. After
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301 deflate has returned Z_STREAM_END, the only possible operations on the
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302 stream are deflateReset or deflateEnd.
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303
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304 Z_FINISH can be used immediately after deflateInit if all the compression
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305 is to be done in a single step. In this case, avail_out must be at least
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306 the value returned by deflateBound (see below). If deflate does not return
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307 Z_STREAM_END, then it must be called again as described above.
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308
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309 deflate() sets strm->adler to the adler32 checksum of all input read
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310 so far (that is, total_in bytes).
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311
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312 deflate() may update strm->data_type if it can make a good guess about
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313 the input data type (Z_BINARY or Z_TEXT). In doubt, the data is considered
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314 binary. This field is only for information purposes and does not affect
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315 the compression algorithm in any manner.
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316
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317 deflate() returns Z_OK if some progress has been made (more input
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318 processed or more output produced), Z_STREAM_END if all input has been
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319 consumed and all output has been produced (only when flush is set to
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320 Z_FINISH), Z_STREAM_ERROR if the stream state was inconsistent (for example
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321 if next_in or next_out was NULL), Z_BUF_ERROR if no progress is possible
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322 (for example avail_in or avail_out was zero). Note that Z_BUF_ERROR is not
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323 fatal, and deflate() can be called again with more input and more output
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324 space to continue compressing.
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325 */
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326
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327
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328 ZEXTERN int ZEXPORT deflateEnd OF((z_streamp strm));
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329 /*
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330 All dynamically allocated data structures for this stream are freed.
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331 This function discards any unprocessed input and does not flush any
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332 pending output.
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333
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334 deflateEnd returns Z_OK if success, Z_STREAM_ERROR if the
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335 stream state was inconsistent, Z_DATA_ERROR if the stream was freed
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336 prematurely (some input or output was discarded). In the error case,
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337 msg may be set but then points to a static string (which must not be
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338 deallocated).
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339 */
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340
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341
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342 /*
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343 ZEXTERN int ZEXPORT inflateInit OF((z_streamp strm));
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344
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345 Initializes the internal stream state for decompression. The fields
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346 next_in, avail_in, zalloc, zfree and opaque must be initialized before by
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347 the caller. If next_in is not Z_NULL and avail_in is large enough (the exact
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348 value depends on the compression method), inflateInit determines the
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349 compression method from the zlib header and allocates all data structures
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350 accordingly; otherwise the allocation will be deferred to the first call of
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351 inflate. If zalloc and zfree are set to Z_NULL, inflateInit updates them to
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352 use default allocation functions.
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353
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354 inflateInit returns Z_OK if success, Z_MEM_ERROR if there was not enough
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355 memory, Z_VERSION_ERROR if the zlib library version is incompatible with the
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356 version assumed by the caller. msg is set to null if there is no error
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357 message. inflateInit does not perform any decompression apart from reading
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358 the zlib header if present: this will be done by inflate(). (So next_in and
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359 avail_in may be modified, but next_out and avail_out are unchanged.)
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360 */
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361
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362
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363 ZEXTERN int ZEXPORT inflate OF((z_streamp strm, int flush));
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364 /*
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365 inflate decompresses as much data as possible, and stops when the input
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366 buffer becomes empty or the output buffer becomes full. It may introduce
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367 some output latency (reading input without producing any output) except when
|
|
|
368 forced to flush.
|
|
|
369
|
|
|
370 The detailed semantics are as follows. inflate performs one or both of the
|
|
|
371 following actions:
|
|
|
372
|
|
|
373 - Decompress more input starting at next_in and update next_in and avail_in
|
|
|
374 accordingly. If not all input can be processed (because there is not
|
|
|
375 enough room in the output buffer), next_in is updated and processing
|
|
|
376 will resume at this point for the next call of inflate().
|
|
|
377
|
|
|
378 - Provide more output starting at next_out and update next_out and avail_out
|
|
|
379 accordingly. inflate() provides as much output as possible, until there
|
|
|
380 is no more input data or no more space in the output buffer (see below
|
|
|
381 about the flush parameter).
|
|
|
382
|
|
|
383 Before the call of inflate(), the application should ensure that at least
|
|
|
384 one of the actions is possible, by providing more input and/or consuming
|
|
|
385 more output, and updating the next_* and avail_* values accordingly.
|
|
|
386 The application can consume the uncompressed output when it wants, for
|
|
|
387 example when the output buffer is full (avail_out == 0), or after each
|
|
|
388 call of inflate(). If inflate returns Z_OK and with zero avail_out, it
|
|
|
389 must be called again after making room in the output buffer because there
|
|
|
390 might be more output pending.
|
|
|
391
|
|
|
392 The flush parameter of inflate() can be Z_NO_FLUSH, Z_SYNC_FLUSH,
|
|
|
393 Z_FINISH, or Z_BLOCK. Z_SYNC_FLUSH requests that inflate() flush as much
|
|
|
394 output as possible to the output buffer. Z_BLOCK requests that inflate() stop
|
|
|
395 if and when it gets to the next deflate block boundary. When decoding the
|
|
|
396 zlib or gzip format, this will cause inflate() to return immediately after
|
|
|
397 the header and before the first block. When doing a raw inflate, inflate()
|
|
|
398 will go ahead and process the first block, and will return when it gets to
|
|
|
399 the end of that block, or when it runs out of data.
|
|
|
400
|
|
|
401 The Z_BLOCK option assists in appending to or combining deflate streams.
|
|
|
402 Also to assist in this, on return inflate() will set strm->data_type to the
|
|
|
403 number of unused bits in the last byte taken from strm->next_in, plus 64
|
|
|
404 if inflate() is currently decoding the last block in the deflate stream,
|
|
|
405 plus 128 if inflate() returned immediately after decoding an end-of-block
|
|
|
406 code or decoding the complete header up to just before the first byte of the
|
|
|
407 deflate stream. The end-of-block will not be indicated until all of the
|
|
|
408 uncompressed data from that block has been written to strm->next_out. The
|
|
|
409 number of unused bits may in general be greater than seven, except when
|
|
|
410 bit 7 of data_type is set, in which case the number of unused bits will be
|
|
|
411 less than eight.
|
|
|
412
|
|
|
413 inflate() should normally be called until it returns Z_STREAM_END or an
|
|
|
414 error. However if all decompression is to be performed in a single step
|
|
|
415 (a single call of inflate), the parameter flush should be set to
|
|
|
416 Z_FINISH. In this case all pending input is processed and all pending
|
|
|
417 output is flushed; avail_out must be large enough to hold all the
|
|
|
418 uncompressed data. (The size of the uncompressed data may have been saved
|
|
|
419 by the compressor for this purpose.) The next operation on this stream must
|
|
|
420 be inflateEnd to deallocate the decompression state. The use of Z_FINISH
|
|
|
421 is never required, but can be used to inform inflate that a faster approach
|
|
|
422 may be used for the single inflate() call.
|
|
|
423
|
|
|
424 In this implementation, inflate() always flushes as much output as
|
|
|
425 possible to the output buffer, and always uses the faster approach on the
|
|
|
426 first call. So the only effect of the flush parameter in this implementation
|
|
|
427 is on the return value of inflate(), as noted below, or when it returns early
|
|
|
428 because Z_BLOCK is used.
|
|
|
429
|
|
|
430 If a preset dictionary is needed after this call (see inflateSetDictionary
|
|
|
431 below), inflate sets strm->adler to the adler32 checksum of the dictionary
|
|
|
432 chosen by the compressor and returns Z_NEED_DICT; otherwise it sets
|
|
|
433 strm->adler to the adler32 checksum of all output produced so far (that is,
|
|
|
434 total_out bytes) and returns Z_OK, Z_STREAM_END or an error code as described
|
|
|
435 below. At the end of the stream, inflate() checks that its computed adler32
|
|
|
436 checksum is equal to that saved by the compressor and returns Z_STREAM_END
|
|
|
437 only if the checksum is correct.
|
|
|
438
|
|
|
439 inflate() will decompress and check either zlib-wrapped or gzip-wrapped
|
|
|
440 deflate data. The header type is detected automatically. Any information
|
|
|
441 contained in the gzip header is not retained, so applications that need that
|
|
|
442 information should instead use raw inflate, see inflateInit2() below, or
|
|
|
443 inflateBack() and perform their own processing of the gzip header and
|
|
|
444 trailer.
|
|
|
445
|
|
|
446 inflate() returns Z_OK if some progress has been made (more input processed
|
|
|
447 or more output produced), Z_STREAM_END if the end of the compressed data has
|
|
|
448 been reached and all uncompressed output has been produced, Z_NEED_DICT if a
|
|
|
449 preset dictionary is needed at this point, Z_DATA_ERROR if the input data was
|
|
|
450 corrupted (input stream not conforming to the zlib format or incorrect check
|
|
|
451 value), Z_STREAM_ERROR if the stream structure was inconsistent (for example
|
|
|
452 if next_in or next_out was NULL), Z_MEM_ERROR if there was not enough memory,
|
|
|
453 Z_BUF_ERROR if no progress is possible or if there was not enough room in the
|
|
|
454 output buffer when Z_FINISH is used. Note that Z_BUF_ERROR is not fatal, and
|
|
|
455 inflate() can be called again with more input and more output space to
|
|
|
456 continue decompressing. If Z_DATA_ERROR is returned, the application may then
|
|
|
457 call inflateSync() to look for a good compression block if a partial recovery
|
|
|
458 of the data is desired.
|
|
|
459 */
|
|
|
460
|
|
|
461
|
|
|
462 ZEXTERN int ZEXPORT inflateEnd OF((z_streamp strm));
|
|
|
463 /*
|
|
|
464 All dynamically allocated data structures for this stream are freed.
|
|
|
465 This function discards any unprocessed input and does not flush any
|
|
|
466 pending output.
|
|
|
467
|
|
|
468 inflateEnd returns Z_OK if success, Z_STREAM_ERROR if the stream state
|
|
|
469 was inconsistent. In the error case, msg may be set but then points to a
|
|
|
470 static string (which must not be deallocated).
|
|
|
471 */
|
|
|
472
|
|
|
473 /* Advanced functions */
|
|
|
474
|
|
|
475 /*
|
|
|
476 The following functions are needed only in some special applications.
|
|
|
477 */
|
|
|
478
|
|
|
479 /*
|
|
|
480 ZEXTERN int ZEXPORT deflateInit2 OF((z_streamp strm,
|
|
|
481 int level,
|
|
|
482 int method,
|
|
|
483 int windowBits,
|
|
|
484 int memLevel,
|
|
|
485 int strategy));
|
|
|
486
|
|
|
487 This is another version of deflateInit with more compression options. The
|
|
|
488 fields next_in, zalloc, zfree and opaque must be initialized before by
|
|
|
489 the caller.
|
|
|
490
|
|
|
491 The method parameter is the compression method. It must be Z_DEFLATED in
|
|
|
492 this version of the library.
|
|
|
493
|
|
|
494 The windowBits parameter is the base two logarithm of the window size
|
|
|
495 (the size of the history buffer). It should be in the range 8..15 for this
|
|
|
496 version of the library. Larger values of this parameter result in better
|
|
|
497 compression at the expense of memory usage. The default value is 15 if
|
|
|
498 deflateInit is used instead.
|
|
|
499
|
|
|
500 windowBits can also be -8..-15 for raw deflate. In this case, -windowBits
|
|
|
501 determines the window size. deflate() will then generate raw deflate data
|
|
|
502 with no zlib header or trailer, and will not compute an adler32 check value.
|
|
|
503
|
|
|
504 windowBits can also be greater than 15 for optional gzip encoding. Add
|
|
|
505 16 to windowBits to write a simple gzip header and trailer around the
|
|
|
506 compressed data instead of a zlib wrapper. The gzip header will have no
|
|
|
507 file name, no extra data, no comment, no modification time (set to zero),
|
|
|
508 no header crc, and the operating system will be set to 255 (unknown). If a
|
|
|
509 gzip stream is being written, strm->adler is a crc32 instead of an adler32.
|
|
|
510
|
|
|
511 The memLevel parameter specifies how much memory should be allocated
|
|
|
512 for the internal compression state. memLevel=1 uses minimum memory but
|
|
|
513 is slow and reduces compression ratio; memLevel=9 uses maximum memory
|
|
|
514 for optimal speed. The default value is 8. See zconf.h for total memory
|
|
|
515 usage as a function of windowBits and memLevel.
|
|
|
516
|
|
|
517 The strategy parameter is used to tune the compression algorithm. Use the
|
|
|
518 value Z_DEFAULT_STRATEGY for normal data, Z_FILTERED for data produced by a
|
|
|
519 filter (or predictor), Z_HUFFMAN_ONLY to force Huffman encoding only (no
|
|
|
520 string match), or Z_RLE to limit match distances to one (run-length
|
|
|
521 encoding). Filtered data consists mostly of small values with a somewhat
|
|
|
522 random distribution. In this case, the compression algorithm is tuned to
|
|
|
523 compress them better. The effect of Z_FILTERED is to force more Huffman
|
|
|
524 coding and less string matching; it is somewhat intermediate between
|
|
|
525 Z_DEFAULT and Z_HUFFMAN_ONLY. Z_RLE is designed to be almost as fast as
|
|
|
526 Z_HUFFMAN_ONLY, but give better compression for PNG image data. The strategy
|
|
|
527 parameter only affects the compression ratio but not the correctness of the
|
|
|
528 compressed output even if it is not set appropriately. Z_FIXED prevents the
|
|
|
529 use of dynamic Huffman codes, allowing for a simpler decoder for special
|
|
|
530 applications.
|
|
|
531
|
|
|
532 deflateInit2 returns Z_OK if success, Z_MEM_ERROR if there was not enough
|
|
|
533 memory, Z_STREAM_ERROR if a parameter is invalid (such as an invalid
|
|
|
534 method). msg is set to null if there is no error message. deflateInit2 does
|
|
|
535 not perform any compression: this will be done by deflate().
|
|
|
536 */
|
|
|
537
|
|
|
538 ZEXTERN int ZEXPORT deflateSetDictionary OF((z_streamp strm,
|
|
|
539 const Bytef *dictionary,
|
|
|
540 uInt dictLength));
|
|
|
541 /*
|
|
|
542 Initializes the compression dictionary from the given byte sequence
|
|
|
543 without producing any compressed output. This function must be called
|
|
|
544 immediately after deflateInit, deflateInit2 or deflateReset, before any
|
|
|
545 call of deflate. The compressor and decompressor must use exactly the same
|
|
|
546 dictionary (see inflateSetDictionary).
|
|
|
547
|
|
|
548 The dictionary should consist of strings (byte sequences) that are likely
|
|
|
549 to be encountered later in the data to be compressed, with the most commonly
|
|
|
550 used strings preferably put towards the end of the dictionary. Using a
|
|
|
551 dictionary is most useful when the data to be compressed is short and can be
|
|
|
552 predicted with good accuracy; the data can then be compressed better than
|
|
|
553 with the default empty dictionary.
|
|
|
554
|
|
|
555 Depending on the size of the compression data structures selected by
|
|
|
556 deflateInit or deflateInit2, a part of the dictionary may in effect be
|
|
|
557 discarded, for example if the dictionary is larger than the window size in
|
|
|
558 deflate or deflate2. Thus the strings most likely to be useful should be
|
|
|
559 put at the end of the dictionary, not at the front. In addition, the
|
|
|
560 current implementation of deflate will use at most the window size minus
|
|
|
561 262 bytes of the provided dictionary.
|
|
|
562
|
|
|
563 Upon return of this function, strm->adler is set to the adler32 value
|
|
|
564 of the dictionary; the decompressor may later use this value to determine
|
|
|
565 which dictionary has been used by the compressor. (The adler32 value
|
|
|
566 applies to the whole dictionary even if only a subset of the dictionary is
|
|
|
567 actually used by the compressor.) If a raw deflate was requested, then the
|
|
|
568 adler32 value is not computed and strm->adler is not set.
|
|
|
569
|
|
|
570 deflateSetDictionary returns Z_OK if success, or Z_STREAM_ERROR if a
|
|
|
571 parameter is invalid (such as NULL dictionary) or the stream state is
|
|
|
572 inconsistent (for example if deflate has already been called for this stream
|
|
|
573 or if the compression method is bsort). deflateSetDictionary does not
|
|
|
574 perform any compression: this will be done by deflate().
|
|
|
575 */
|
|
|
576
|
|
|
577 ZEXTERN int ZEXPORT deflateCopy OF((z_streamp dest,
|
|
|
578 z_streamp source));
|
|
|
579 /*
|
|
|
580 Sets the destination stream as a complete copy of the source stream.
|
|
|
581
|
|
|
582 This function can be useful when several compression strategies will be
|
|
|
583 tried, for example when there are several ways of pre-processing the input
|
|
|
584 data with a filter. The streams that will be discarded should then be freed
|
|
|
585 by calling deflateEnd. Note that deflateCopy duplicates the internal
|
|
|
586 compression state which can be quite large, so this strategy is slow and
|
|
|
587 can consume lots of memory.
|
|
|
588
|
|
|
589 deflateCopy returns Z_OK if success, Z_MEM_ERROR if there was not
|
|
|
590 enough memory, Z_STREAM_ERROR if the source stream state was inconsistent
|
|
|
591 (such as zalloc being NULL). msg is left unchanged in both source and
|
|
|
592 destination.
|
|
|
593 */
|
|
|
594
|
|
|
595 ZEXTERN int ZEXPORT deflateReset OF((z_streamp strm));
|
|
|
596 /*
|
|
|
597 This function is equivalent to deflateEnd followed by deflateInit,
|
|
|
598 but does not free and reallocate all the internal compression state.
|
|
|
599 The stream will keep the same compression level and any other attributes
|
|
|
600 that may have been set by deflateInit2.
|
|
|
601
|
|
|
602 deflateReset returns Z_OK if success, or Z_STREAM_ERROR if the source
|
|
|
603 stream state was inconsistent (such as zalloc or state being NULL).
|
|
|
604 */
|
|
|
605
|
|
|
606 ZEXTERN int ZEXPORT deflateParams OF((z_streamp strm,
|
|
|
607 int level,
|
|
|
608 int strategy));
|
|
|
609 /*
|
|
|
610 Dynamically update the compression level and compression strategy. The
|
|
|
611 interpretation of level and strategy is as in deflateInit2. This can be
|
|
|
612 used to switch between compression and straight copy of the input data, or
|
|
|
613 to switch to a different kind of input data requiring a different
|
|
|
614 strategy. If the compression level is changed, the input available so far
|
|
|
615 is compressed with the old level (and may be flushed); the new level will
|
|
|
616 take effect only at the next call of deflate().
|
|
|
617
|
|
|
618 Before the call of deflateParams, the stream state must be set as for
|
|
|
619 a call of deflate(), since the currently available input may have to
|
|
|
620 be compressed and flushed. In particular, strm->avail_out must be non-zero.
|
|
|
621
|
|
|
622 deflateParams returns Z_OK if success, Z_STREAM_ERROR if the source
|
|
|
623 stream state was inconsistent or if a parameter was invalid, Z_BUF_ERROR
|
|
|
624 if strm->avail_out was zero.
|
|
|
625 */
|
|
|
626
|
|
|
627 ZEXTERN int ZEXPORT deflateTune OF((z_streamp strm,
|
|
|
628 int good_length,
|
|
|
629 int max_lazy,
|
|
|
630 int nice_length,
|
|
|
631 int max_chain));
|
|
|
632 /*
|
|
|
633 Fine tune deflate's internal compression parameters. This should only be
|
|
|
634 used by someone who understands the algorithm used by zlib's deflate for
|
|
|
635 searching for the best matching string, and even then only by the most
|
|
|
636 fanatic optimizer trying to squeeze out the last compressed bit for their
|
|
|
637 specific input data. Read the deflate.c source code for the meaning of the
|
|
|
638 max_lazy, good_length, nice_length, and max_chain parameters.
|
|
|
639
|
|
|
640 deflateTune() can be called after deflateInit() or deflateInit2(), and
|
|
|
641 returns Z_OK on success, or Z_STREAM_ERROR for an invalid deflate stream.
|
|
|
642 */
|
|
|
643
|
|
|
644 ZEXTERN uLong ZEXPORT deflateBound OF((z_streamp strm,
|
|
|
645 uLong sourceLen));
|
|
|
646 /*
|
|
|
647 deflateBound() returns an upper bound on the compressed size after
|
|
|
648 deflation of sourceLen bytes. It must be called after deflateInit()
|
|
|
649 or deflateInit2(). This would be used to allocate an output buffer
|
|
|
650 for deflation in a single pass, and so would be called before deflate().
|
|
|
651 */
|
|
|
652
|
|
|
653 ZEXTERN int ZEXPORT deflatePrime OF((z_streamp strm,
|
|
|
654 int bits,
|
|
|
655 int value));
|
|
|
656 /*
|
|
|
657 deflatePrime() inserts bits in the deflate output stream. The intent
|
|
|
658 is that this function is used to start off the deflate output with the
|
|
|
659 bits leftover from a previous deflate stream when appending to it. As such,
|
|
|
660 this function can only be used for raw deflate, and must be used before the
|
|
|
661 first deflate() call after a deflateInit2() or deflateReset(). bits must be
|
|
|
662 less than or equal to 16, and that many of the least significant bits of
|
|
|
663 value will be inserted in the output.
|
|
|
664
|
|
|
665 deflatePrime returns Z_OK if success, or Z_STREAM_ERROR if the source
|
|
|
666 stream state was inconsistent.
|
|
|
667 */
|
|
|
668
|
|
|
669 ZEXTERN int ZEXPORT deflateSetHeader OF((z_streamp strm,
|
|
|
670 gz_headerp head));
|
|
|
671 /*
|
|
|
672 deflateSetHeader() provides gzip header information for when a gzip
|
|
|
673 stream is requested by deflateInit2(). deflateSetHeader() may be called
|
|
|
674 after deflateInit2() or deflateReset() and before the first call of
|
|
|
675 deflate(). The text, time, os, extra field, name, and comment information
|
|
|
676 in the provided gz_header structure are written to the gzip header (xflag is
|
|
|
677 ignored -- the extra flags are set according to the compression level). The
|
|
|
678 caller must assure that, if not Z_NULL, name and comment are terminated with
|
|
|
679 a zero byte, and that if extra is not Z_NULL, that extra_len bytes are
|
|
|
680 available there. If hcrc is true, a gzip header crc is included. Note that
|
|
|
681 the current versions of the command-line version of gzip (up through version
|
|
|
682 1.3.x) do not support header crc's, and will report that it is a "multi-part
|
|
|
683 gzip file" and give up.
|
|
|
684
|
|
|
685 If deflateSetHeader is not used, the default gzip header has text false,
|
|
|
686 the time set to zero, and os set to 255, with no extra, name, or comment
|
|
|
687 fields. The gzip header is returned to the default state by deflateReset().
|
|
|
688
|
|
|
689 deflateSetHeader returns Z_OK if success, or Z_STREAM_ERROR if the source
|
|
|
690 stream state was inconsistent.
|
|
|
691 */
|
|
|
692
|
|
|
693 /*
|
|
|
694 ZEXTERN int ZEXPORT inflateInit2 OF((z_streamp strm,
|
|
|
695 int windowBits));
|
|
|
696
|
|
|
697 This is another version of inflateInit with an extra parameter. The
|
|
|
698 fields next_in, avail_in, zalloc, zfree and opaque must be initialized
|
|
|
699 before by the caller.
|
|
|
700
|
|
|
701 The windowBits parameter is the base two logarithm of the maximum window
|
|
|
702 size (the size of the history buffer). It should be in the range 8..15 for
|
|
|
703 this version of the library. The default value is 15 if inflateInit is used
|
|
|
704 instead. windowBits must be greater than or equal to the windowBits value
|
|
|
705 provided to deflateInit2() while compressing, or it must be equal to 15 if
|
|
|
706 deflateInit2() was not used. If a compressed stream with a larger window
|
|
|
707 size is given as input, inflate() will return with the error code
|
|
|
708 Z_DATA_ERROR instead of trying to allocate a larger window.
|
|
|
709
|
|
|
710 windowBits can also be -8..-15 for raw inflate. In this case, -windowBits
|
|
|
711 determines the window size. inflate() will then process raw deflate data,
|
|
|
712 not looking for a zlib or gzip header, not generating a check value, and not
|
|
|
713 looking for any check values for comparison at the end of the stream. This
|
|
|
714 is for use with other formats that use the deflate compressed data format
|
|
|
715 such as zip. Those formats provide their own check values. If a custom
|
|
|
716 format is developed using the raw deflate format for compressed data, it is
|
|
|
717 recommended that a check value such as an adler32 or a crc32 be applied to
|
|
|
718 the uncompressed data as is done in the zlib, gzip, and zip formats. For
|
|
|
719 most applications, the zlib format should be used as is. Note that comments
|
|
|
720 above on the use in deflateInit2() applies to the magnitude of windowBits.
|
|
|
721
|
|
|
722 windowBits can also be greater than 15 for optional gzip decoding. Add
|
|
|
723 32 to windowBits to enable zlib and gzip decoding with automatic header
|
|
|
724 detection, or add 16 to decode only the gzip format (the zlib format will
|
|
|
725 return a Z_DATA_ERROR). If a gzip stream is being decoded, strm->adler is
|
|
|
726 a crc32 instead of an adler32.
|
|
|
727
|
|
|
728 inflateInit2 returns Z_OK if success, Z_MEM_ERROR if there was not enough
|
|
|
729 memory, Z_STREAM_ERROR if a parameter is invalid (such as a null strm). msg
|
|
|
730 is set to null if there is no error message. inflateInit2 does not perform
|
|
|
731 any decompression apart from reading the zlib header if present: this will
|
|
|
732 be done by inflate(). (So next_in and avail_in may be modified, but next_out
|
|
|
733 and avail_out are unchanged.)
|
|
|
734 */
|
|
|
735
|
|
|
736 ZEXTERN int ZEXPORT inflateSetDictionary OF((z_streamp strm,
|
|
|
737 const Bytef *dictionary,
|
|
|
738 uInt dictLength));
|
|
|
739 /*
|
|
|
740 Initializes the decompression dictionary from the given uncompressed byte
|
|
|
741 sequence. This function must be called immediately after a call of inflate,
|
|
|
742 if that call returned Z_NEED_DICT. The dictionary chosen by the compressor
|
|
|
743 can be determined from the adler32 value returned by that call of inflate.
|
|
|
744 The compressor and decompressor must use exactly the same dictionary (see
|
|
|
745 deflateSetDictionary). For raw inflate, this function can be called
|
|
|
746 immediately after inflateInit2() or inflateReset() and before any call of
|
|
|
747 inflate() to set the dictionary. The application must insure that the
|
|
|
748 dictionary that was used for compression is provided.
|
|
|
749
|
|
|
750 inflateSetDictionary returns Z_OK if success, Z_STREAM_ERROR if a
|
|
|
751 parameter is invalid (such as NULL dictionary) or the stream state is
|
|
|
752 inconsistent, Z_DATA_ERROR if the given dictionary doesn't match the
|
|
|
753 expected one (incorrect adler32 value). inflateSetDictionary does not
|
|
|
754 perform any decompression: this will be done by subsequent calls of
|
|
|
755 inflate().
|
|
|
756 */
|
|
|
757
|
|
|
758 ZEXTERN int ZEXPORT inflateSync OF((z_streamp strm));
|
|
|
759 /*
|
|
|
760 Skips invalid compressed data until a full flush point (see above the
|
|
|
761 description of deflate with Z_FULL_FLUSH) can be found, or until all
|
|
|
762 available input is skipped. No output is provided.
|
|
|
763
|
|
|
764 inflateSync returns Z_OK if a full flush point has been found, Z_BUF_ERROR
|
|
|
765 if no more input was provided, Z_DATA_ERROR if no flush point has been found,
|
|
|
766 or Z_STREAM_ERROR if the stream structure was inconsistent. In the success
|
|
|
767 case, the application may save the current current value of total_in which
|
|
|
768 indicates where valid compressed data was found. In the error case, the
|
|
|
769 application may repeatedly call inflateSync, providing more input each time,
|
|
|
770 until success or end of the input data.
|
|
|
771 */
|
|
|
772
|
|
|
773 ZEXTERN int ZEXPORT inflateCopy OF((z_streamp dest,
|
|
|
774 z_streamp source));
|
|
|
775 /*
|
|
|
776 Sets the destination stream as a complete copy of the source stream.
|
|
|
777
|
|
|
778 This function can be useful when randomly accessing a large stream. The
|
|
|
779 first pass through the stream can periodically record the inflate state,
|
|
|
780 allowing restarting inflate at those points when randomly accessing the
|
|
|
781 stream.
|
|
|
782
|
|
|
783 inflateCopy returns Z_OK if success, Z_MEM_ERROR if there was not
|
|
|
784 enough memory, Z_STREAM_ERROR if the source stream state was inconsistent
|
|
|
785 (such as zalloc being NULL). msg is left unchanged in both source and
|
|
|
786 destination.
|
|
|
787 */
|
|
|
788
|
|
|
789 ZEXTERN int ZEXPORT inflateReset OF((z_streamp strm));
|
|
|
790 /*
|
|
|
791 This function is equivalent to inflateEnd followed by inflateInit,
|
|
|
792 but does not free and reallocate all the internal decompression state.
|
|
|
793 The stream will keep attributes that may have been set by inflateInit2.
|
|
|
794
|
|
|
795 inflateReset returns Z_OK if success, or Z_STREAM_ERROR if the source
|
|
|
796 stream state was inconsistent (such as zalloc or state being NULL).
|
|
|
797 */
|
|
|
798
|
|
|
799 ZEXTERN int ZEXPORT inflatePrime OF((z_streamp strm,
|
|
|
800 int bits,
|
|
|
801 int value));
|
|
|
802 /*
|
|
|
803 This function inserts bits in the inflate input stream. The intent is
|
|
|
804 that this function is used to start inflating at a bit position in the
|
|
|
805 middle of a byte. The provided bits will be used before any bytes are used
|
|
|
806 from next_in. This function should only be used with raw inflate, and
|
|
|
807 should be used before the first inflate() call after inflateInit2() or
|
|
|
808 inflateReset(). bits must be less than or equal to 16, and that many of the
|
|
|
809 least significant bits of value will be inserted in the input.
|
|
|
810
|
|
|
811 inflatePrime returns Z_OK if success, or Z_STREAM_ERROR if the source
|
|
|
812 stream state was inconsistent.
|
|
|
813 */
|
|
|
814
|
|
|
815 ZEXTERN int ZEXPORT inflateGetHeader OF((z_streamp strm,
|
|
|
816 gz_headerp head));
|
|
|
817 /*
|
|
|
818 inflateGetHeader() requests that gzip header information be stored in the
|
|
|
819 provided gz_header structure. inflateGetHeader() may be called after
|
|
|
820 inflateInit2() or inflateReset(), and before the first call of inflate().
|
|
|
821 As inflate() processes the gzip stream, head->done is zero until the header
|
|
|
822 is completed, at which time head->done is set to one. If a zlib stream is
|
|
|
823 being decoded, then head->done is set to -1 to indicate that there will be
|
|
|
824 no gzip header information forthcoming. Note that Z_BLOCK can be used to
|
|
|
825 force inflate() to return immediately after header processing is complete
|
|
|
826 and before any actual data is decompressed.
|
|
|
827
|
|
|
828 The text, time, xflags, and os fields are filled in with the gzip header
|
|
|
829 contents. hcrc is set to true if there is a header CRC. (The header CRC
|
|
|
830 was valid if done is set to one.) If extra is not Z_NULL, then extra_max
|
|
|
831 contains the maximum number of bytes to write to extra. Once done is true,
|
|
|
832 extra_len contains the actual extra field length, and extra contains the
|
|
|
833 extra field, or that field truncated if extra_max is less than extra_len.
|
|
|
834 If name is not Z_NULL, then up to name_max characters are written there,
|
|
|
835 terminated with a zero unless the length is greater than name_max. If
|
|
|
836 comment is not Z_NULL, then up to comm_max characters are written there,
|
|
|
837 terminated with a zero unless the length is greater than comm_max. When
|
|
|
838 any of extra, name, or comment are not Z_NULL and the respective field is
|
|
|
839 not present in the header, then that field is set to Z_NULL to signal its
|
|
|
840 absence. This allows the use of deflateSetHeader() with the returned
|
|
|
841 structure to duplicate the header. However if those fields are set to
|
|
|
842 allocated memory, then the application will need to save those pointers
|
|
|
843 elsewhere so that they can be eventually freed.
|
|
|
844
|
|
|
845 If inflateGetHeader is not used, then the header information is simply
|
|
|
846 discarded. The header is always checked for validity, including the header
|
|
|
847 CRC if present. inflateReset() will reset the process to discard the header
|
|
|
848 information. The application would need to call inflateGetHeader() again to
|
|
|
849 retrieve the header from the next gzip stream.
|
|
|
850
|
|
|
851 inflateGetHeader returns Z_OK if success, or Z_STREAM_ERROR if the source
|
|
|
852 stream state was inconsistent.
|
|
|
853 */
|
|
|
854
|
|
|
855 /*
|
|
|
856 ZEXTERN int ZEXPORT inflateBackInit OF((z_streamp strm, int windowBits,
|
|
|
857 unsigned char FAR *window));
|
|
|
858
|
|
|
859 Initialize the internal stream state for decompression using inflateBack()
|
|
|
860 calls. The fields zalloc, zfree and opaque in strm must be initialized
|
|
|
861 before the call. If zalloc and zfree are Z_NULL, then the default library-
|
|
|
862 derived memory allocation routines are used. windowBits is the base two
|
|
|
863 logarithm of the window size, in the range 8..15. window is a caller
|
|
|
864 supplied buffer of that size. Except for special applications where it is
|
|
|
865 assured that deflate was used with small window sizes, windowBits must be 15
|
|
|
866 and a 32K byte window must be supplied to be able to decompress general
|
|
|
867 deflate streams.
|
|
|
868
|
|
|
869 See inflateBack() for the usage of these routines.
|
|
|
870
|
|
|
871 inflateBackInit will return Z_OK on success, Z_STREAM_ERROR if any of
|
|
|
872 the paramaters are invalid, Z_MEM_ERROR if the internal state could not
|
|
|
873 be allocated, or Z_VERSION_ERROR if the version of the library does not
|
|
|
874 match the version of the header file.
|
|
|
875 */
|
|
|
876
|
|
|
877 typedef unsigned (*in_func) OF((void FAR *, unsigned char FAR * FAR *));
|
|
|
878 typedef int (*out_func) OF((void FAR *, unsigned char FAR *, unsigned));
|
|
|
879
|
|
|
880 ZEXTERN int ZEXPORT inflateBack OF((z_streamp strm,
|
|
|
881 in_func in, void FAR *in_desc,
|
|
|
882 out_func out, void FAR *out_desc));
|
|
|
883 /*
|
|
|
884 inflateBack() does a raw inflate with a single call using a call-back
|
|
|
885 interface for input and output. This is more efficient than inflate() for
|
|
|
886 file i/o applications in that it avoids copying between the output and the
|
|
|
887 sliding window by simply making the window itself the output buffer. This
|
|
|
888 function trusts the application to not change the output buffer passed by
|
|
|
889 the output function, at least until inflateBack() returns.
|
|
|
890
|
|
|
891 inflateBackInit() must be called first to allocate the internal state
|
|
|
892 and to initialize the state with the user-provided window buffer.
|
|
|
893 inflateBack() may then be used multiple times to inflate a complete, raw
|
|
|
894 deflate stream with each call. inflateBackEnd() is then called to free
|
|
|
895 the allocated state.
|
|
|
896
|
|
|
897 A raw deflate stream is one with no zlib or gzip header or trailer.
|
|
|
898 This routine would normally be used in a utility that reads zip or gzip
|
|
|
899 files and writes out uncompressed files. The utility would decode the
|
|
|
900 header and process the trailer on its own, hence this routine expects
|
|
|
901 only the raw deflate stream to decompress. This is different from the
|
|
|
902 normal behavior of inflate(), which expects either a zlib or gzip header and
|
|
|
903 trailer around the deflate stream.
|
|
|
904
|
|
|
905 inflateBack() uses two subroutines supplied by the caller that are then
|
|
|
906 called by inflateBack() for input and output. inflateBack() calls those
|
|
|
907 routines until it reads a complete deflate stream and writes out all of the
|
|
|
908 uncompressed data, or until it encounters an error. The function's
|
|
|
909 parameters and return types are defined above in the in_func and out_func
|
|
|
910 typedefs. inflateBack() will call in(in_desc, &buf) which should return the
|
|
|
911 number of bytes of provided input, and a pointer to that input in buf. If
|
|
|
912 there is no input available, in() must return zero--buf is ignored in that
|
|
|
913 case--and inflateBack() will return a buffer error. inflateBack() will call
|
|
|
914 out(out_desc, buf, len) to write the uncompressed data buf[0..len-1]. out()
|
|
|
915 should return zero on success, or non-zero on failure. If out() returns
|
|
|
916 non-zero, inflateBack() will return with an error. Neither in() nor out()
|
|
|
917 are permitted to change the contents of the window provided to
|
|
|
918 inflateBackInit(), which is also the buffer that out() uses to write from.
|
|
|
919 The length written by out() will be at most the window size. Any non-zero
|
|
|
920 amount of input may be provided by in().
|
|
|
921
|
|
|
922 For convenience, inflateBack() can be provided input on the first call by
|
|
|
923 setting strm->next_in and strm->avail_in. If that input is exhausted, then
|
|
|
924 in() will be called. Therefore strm->next_in must be initialized before
|
|
|
925 calling inflateBack(). If strm->next_in is Z_NULL, then in() will be called
|
|
|
926 immediately for input. If strm->next_in is not Z_NULL, then strm->avail_in
|
|
|
927 must also be initialized, and then if strm->avail_in is not zero, input will
|
|
|
928 initially be taken from strm->next_in[0 .. strm->avail_in - 1].
|
|
|
929
|
|
|
930 The in_desc and out_desc parameters of inflateBack() is passed as the
|
|
|
931 first parameter of in() and out() respectively when they are called. These
|
|
|
932 descriptors can be optionally used to pass any information that the caller-
|
|
|
933 supplied in() and out() functions need to do their job.
|
|
|
934
|
|
|
935 On return, inflateBack() will set strm->next_in and strm->avail_in to
|
|
|
936 pass back any unused input that was provided by the last in() call. The
|
|
|
937 return values of inflateBack() can be Z_STREAM_END on success, Z_BUF_ERROR
|
|
|
938 if in() or out() returned an error, Z_DATA_ERROR if there was a format
|
|
|
939 error in the deflate stream (in which case strm->msg is set to indicate the
|
|
|
940 nature of the error), or Z_STREAM_ERROR if the stream was not properly
|
|
|
941 initialized. In the case of Z_BUF_ERROR, an input or output error can be
|
|
|
942 distinguished using strm->next_in which will be Z_NULL only if in() returned
|
|
|
943 an error. If strm->next is not Z_NULL, then the Z_BUF_ERROR was due to
|
|
|
944 out() returning non-zero. (in() will always be called before out(), so
|
|
|
945 strm->next_in is assured to be defined if out() returns non-zero.) Note
|
|
|
946 that inflateBack() cannot return Z_OK.
|
|
|
947 */
|
|
|
948
|
|
|
949 ZEXTERN int ZEXPORT inflateBackEnd OF((z_streamp strm));
|
|
|
950 /*
|
|
|
951 All memory allocated by inflateBackInit() is freed.
|
|
|
952
|
|
|
953 inflateBackEnd() returns Z_OK on success, or Z_STREAM_ERROR if the stream
|
|
|
954 state was inconsistent.
|
|
|
955 */
|
|
|
956
|
|
|
957 ZEXTERN uLong ZEXPORT zlibCompileFlags OF((void));
|
|
|
958 /* Return flags indicating compile-time options.
|
|
|
959
|
|
|
960 Type sizes, two bits each, 00 = 16 bits, 01 = 32, 10 = 64, 11 = other:
|
|
|
961 1.0: size of uInt
|
|
|
962 3.2: size of uLong
|
|
|
963 5.4: size of voidpf (pointer)
|
|
|
964 7.6: size of z_off_t
|
|
|
965
|
|
|
966 Compiler, assembler, and debug options:
|
|
|
967 8: DEBUG
|
|
|
968 9: ASMV or ASMINF -- use ASM code
|
|
|
969 10: ZLIB_WINAPI -- exported functions use the WINAPI calling convention
|
|
|
970 11: 0 (reserved)
|
|
|
971
|
|
|
972 One-time table building (smaller code, but not thread-safe if true):
|
|
|
973 12: BUILDFIXED -- build static block decoding tables when needed
|
|
|
974 13: DYNAMIC_CRC_TABLE -- build CRC calculation tables when needed
|
|
|
975 14,15: 0 (reserved)
|
|
|
976
|
|
|
977 Library content (indicates missing functionality):
|
|
|
978 16: NO_GZCOMPRESS -- gz* functions cannot compress (to avoid linking
|
|
|
979 deflate code when not needed)
|
|
|
980 17: NO_GZIP -- deflate can't write gzip streams, and inflate can't detect
|
|
|
981 and decode gzip streams (to avoid linking crc code)
|
|
|
982 18-19: 0 (reserved)
|
|
|
983
|
|
|
984 Operation variations (changes in library functionality):
|
|
|
985 20: PKZIP_BUG_WORKAROUND -- slightly more permissive inflate
|
|
|
986 21: FASTEST -- deflate algorithm with only one, lowest compression level
|
|
|
987 22,23: 0 (reserved)
|
|
|
988
|
|
|
989 The sprintf variant used by gzprintf (zero is best):
|
|
|
990 24: 0 = vs*, 1 = s* -- 1 means limited to 20 arguments after the format
|
|
|
991 25: 0 = *nprintf, 1 = *printf -- 1 means gzprintf() not secure!
|
|
|
992 26: 0 = returns value, 1 = void -- 1 means inferred string length returned
|
|
|
993
|
|
|
994 Remainder:
|
|
|
995 27-31: 0 (reserved)
|
|
|
996 */
|
|
|
997
|
|
|
998
|
|
|
999 /* utility functions */
|
|
|
1000
|
|
|
1001 /*
|
|
|
1002 The following utility functions are implemented on top of the
|
|
|
1003 basic stream-oriented functions. To simplify the interface, some
|
|
|
1004 default options are assumed (compression level and memory usage,
|
|
|
1005 standard memory allocation functions). The source code of these
|
|
|
1006 utility functions can easily be modified if you need special options.
|
|
|
1007 */
|
|
|
1008
|
|
|
1009 ZEXTERN int ZEXPORT compress OF((Bytef *dest, uLongf *destLen,
|
|
|
1010 const Bytef *source, uLong sourceLen));
|
|
|
1011 /*
|
|
|
1012 Compresses the source buffer into the destination buffer. sourceLen is
|
|
|
1013 the byte length of the source buffer. Upon entry, destLen is the total
|
|
|
1014 size of the destination buffer, which must be at least the value returned
|
|
|
1015 by compressBound(sourceLen). Upon exit, destLen is the actual size of the
|
|
|
1016 compressed buffer.
|
|
|
1017 This function can be used to compress a whole file at once if the
|
|
|
1018 input file is mmap'ed.
|
|
|
1019 compress returns Z_OK if success, Z_MEM_ERROR if there was not
|
|
|
1020 enough memory, Z_BUF_ERROR if there was not enough room in the output
|
|
|
1021 buffer.
|
|
|
1022 */
|
|
|
1023
|
|
|
1024 ZEXTERN int ZEXPORT compress2 OF((Bytef *dest, uLongf *destLen,
|
|
|
1025 const Bytef *source, uLong sourceLen,
|
|
|
1026 int level));
|
|
|
1027 /*
|
|
|
1028 Compresses the source buffer into the destination buffer. The level
|
|
|
1029 parameter has the same meaning as in deflateInit. sourceLen is the byte
|
|
|
1030 length of the source buffer. Upon entry, destLen is the total size of the
|
|
|
1031 destination buffer, which must be at least the value returned by
|
|
|
1032 compressBound(sourceLen). Upon exit, destLen is the actual size of the
|
|
|
1033 compressed buffer.
|
|
|
1034
|
|
|
1035 compress2 returns Z_OK if success, Z_MEM_ERROR if there was not enough
|
|
|
1036 memory, Z_BUF_ERROR if there was not enough room in the output buffer,
|
|
|
1037 Z_STREAM_ERROR if the level parameter is invalid.
|
|
|
1038 */
|
|
|
1039
|
|
|
1040 ZEXTERN uLong ZEXPORT compressBound OF((uLong sourceLen));
|
|
|
1041 /*
|
|
|
1042 compressBound() returns an upper bound on the compressed size after
|
|
|
1043 compress() or compress2() on sourceLen bytes. It would be used before
|
|
|
1044 a compress() or compress2() call to allocate the destination buffer.
|
|
|
1045 */
|
|
|
1046
|
|
|
1047 ZEXTERN int ZEXPORT uncompress OF((Bytef *dest, uLongf *destLen,
|
|
|
1048 const Bytef *source, uLong sourceLen));
|
|
|
1049 /*
|
|
|
1050 Decompresses the source buffer into the destination buffer. sourceLen is
|
|
|
1051 the byte length of the source buffer. Upon entry, destLen is the total
|
|
|
1052 size of the destination buffer, which must be large enough to hold the
|
|
|
1053 entire uncompressed data. (The size of the uncompressed data must have
|
|
|
1054 been saved previously by the compressor and transmitted to the decompressor
|
|
|
1055 by some mechanism outside the scope of this compression library.)
|
|
|
1056 Upon exit, destLen is the actual size of the compressed buffer.
|
|
|
1057 This function can be used to decompress a whole file at once if the
|
|
|
1058 input file is mmap'ed.
|
|
|
1059
|
|
|
1060 uncompress returns Z_OK if success, Z_MEM_ERROR if there was not
|
|
|
1061 enough memory, Z_BUF_ERROR if there was not enough room in the output
|
|
|
1062 buffer, or Z_DATA_ERROR if the input data was corrupted or incomplete.
|
|
|
1063 */
|
|
|
1064
|
|
|
1065
|
|
|
1066 typedef voidp gzFile;
|
|
|
1067
|
|
|
1068 ZEXTERN gzFile ZEXPORT gzopen OF((const char *path, const char *mode));
|
|
|
1069 /*
|
|
|
1070 Opens a gzip (.gz) file for reading or writing. The mode parameter
|
|
|
1071 is as in fopen ("rb" or "wb") but can also include a compression level
|
|
|
1072 ("wb9") or a strategy: 'f' for filtered data as in "wb6f", 'h' for
|
|
|
1073 Huffman only compression as in "wb1h", or 'R' for run-length encoding
|
|
|
1074 as in "wb1R". (See the description of deflateInit2 for more information
|
|
|
1075 about the strategy parameter.)
|
|
|
1076
|
|
|
1077 gzopen can be used to read a file which is not in gzip format; in this
|
|
|
1078 case gzread will directly read from the file without decompression.
|
|
|
1079
|
|
|
1080 gzopen returns NULL if the file could not be opened or if there was
|
|
|
1081 insufficient memory to allocate the (de)compression state; errno
|
|
|
1082 can be checked to distinguish the two cases (if errno is zero, the
|
|
|
1083 zlib error is Z_MEM_ERROR). */
|
|
|
1084
|
|
|
1085 ZEXTERN gzFile ZEXPORT gzdopen OF((int fd, const char *mode));
|
|
|
1086 /*
|
|
|
1087 gzdopen() associates a gzFile with the file descriptor fd. File
|
|
|
1088 descriptors are obtained from calls like open, dup, creat, pipe or
|
|
|
1089 fileno (in the file has been previously opened with fopen).
|
|
|
1090 The mode parameter is as in gzopen.
|
|
|
1091 The next call of gzclose on the returned gzFile will also close the
|
|
|
1092 file descriptor fd, just like fclose(fdopen(fd), mode) closes the file
|
|
|
1093 descriptor fd. If you want to keep fd open, use gzdopen(dup(fd), mode).
|
|
|
1094 gzdopen returns NULL if there was insufficient memory to allocate
|
|
|
1095 the (de)compression state.
|
|
|
1096 */
|
|
|
1097
|
|
|
1098 ZEXTERN int ZEXPORT gzsetparams OF((gzFile file, int level, int strategy));
|
|
|
1099 /*
|
|
|
1100 Dynamically update the compression level or strategy. See the description
|
|
|
1101 of deflateInit2 for the meaning of these parameters.
|
|
|
1102 gzsetparams returns Z_OK if success, or Z_STREAM_ERROR if the file was not
|
|
|
1103 opened for writing.
|
|
|
1104 */
|
|
|
1105
|
|
|
1106 ZEXTERN int ZEXPORT gzread OF((gzFile file, voidp buf, unsigned len));
|
|
|
1107 /*
|
|
|
1108 Reads the given number of uncompressed bytes from the compressed file.
|
|
|
1109 If the input file was not in gzip format, gzread copies the given number
|
|
|
1110 of bytes into the buffer.
|
|
|
1111 gzread returns the number of uncompressed bytes actually read (0 for
|
|
|
1112 end of file, -1 for error). */
|
|
|
1113
|
|
|
1114 ZEXTERN int ZEXPORT gzwrite OF((gzFile file,
|
|
|
1115 voidpc buf, unsigned len));
|
|
|
1116 /*
|
|
|
1117 Writes the given number of uncompressed bytes into the compressed file.
|
|
|
1118 gzwrite returns the number of uncompressed bytes actually written
|
|
|
1119 (0 in case of error).
|
|
|
1120 */
|
|
|
1121
|
|
|
1122 ZEXTERN int ZEXPORTVA gzprintf OF((gzFile file, const char *format, ...));
|
|
|
1123 /*
|
|
|
1124 Converts, formats, and writes the args to the compressed file under
|
|
|
1125 control of the format string, as in fprintf. gzprintf returns the number of
|
|
|
1126 uncompressed bytes actually written (0 in case of error). The number of
|
|
|
1127 uncompressed bytes written is limited to 4095. The caller should assure that
|
|
|
1128 this limit is not exceeded. If it is exceeded, then gzprintf() will return
|
|
|
1129 return an error (0) with nothing written. In this case, there may also be a
|
|
|
1130 buffer overflow with unpredictable consequences, which is possible only if
|
|
|
1131 zlib was compiled with the insecure functions sprintf() or vsprintf()
|
|
|
1132 because the secure snprintf() or vsnprintf() functions were not available.
|
|
|
1133 */
|
|
|
1134
|
|
|
1135 ZEXTERN int ZEXPORT gzputs OF((gzFile file, const char *s));
|
|
|
1136 /*
|
|
|
1137 Writes the given null-terminated string to the compressed file, excluding
|
|
|
1138 the terminating null character.
|
|
|
1139 gzputs returns the number of characters written, or -1 in case of error.
|
|
|
1140 */
|
|
|
1141
|
|
|
1142 ZEXTERN char * ZEXPORT gzgets OF((gzFile file, char *buf, int len));
|
|
|
1143 /*
|
|
|
1144 Reads bytes from the compressed file until len-1 characters are read, or
|
|
|
1145 a newline character is read and transferred to buf, or an end-of-file
|
|
|
1146 condition is encountered. The string is then terminated with a null
|
|
|
1147 character.
|
|
|
1148 gzgets returns buf, or Z_NULL in case of error.
|
|
|
1149 */
|
|
|
1150
|
|
|
1151 ZEXTERN int ZEXPORT gzputc OF((gzFile file, int c));
|
|
|
1152 /*
|
|
|
1153 Writes c, converted to an unsigned char, into the compressed file.
|
|
|
1154 gzputc returns the value that was written, or -1 in case of error.
|
|
|
1155 */
|
|
|
1156
|
|
|
1157 ZEXTERN int ZEXPORT gzgetc OF((gzFile file));
|
|
|
1158 /*
|
|
|
1159 Reads one byte from the compressed file. gzgetc returns this byte
|
|
|
1160 or -1 in case of end of file or error.
|
|
|
1161 */
|
|
|
1162
|
|
|
1163 ZEXTERN int ZEXPORT gzungetc OF((int c, gzFile file));
|
|
|
1164 /*
|
|
|
1165 Push one character back onto the stream to be read again later.
|
|
|
1166 Only one character of push-back is allowed. gzungetc() returns the
|
|
|
1167 character pushed, or -1 on failure. gzungetc() will fail if a
|
|
|
1168 character has been pushed but not read yet, or if c is -1. The pushed
|
|
|
1169 character will be discarded if the stream is repositioned with gzseek()
|
|
|
1170 or gzrewind().
|
|
|
1171 */
|
|
|
1172
|
|
|
1173 ZEXTERN int ZEXPORT gzflush OF((gzFile file, int flush));
|
|
|
1174 /*
|
|
|
1175 Flushes all pending output into the compressed file. The parameter
|
|
|
1176 flush is as in the deflate() function. The return value is the zlib
|
|
|
1177 error number (see function gzerror below). gzflush returns Z_OK if
|
|
|
1178 the flush parameter is Z_FINISH and all output could be flushed.
|
|
|
1179 gzflush should be called only when strictly necessary because it can
|
|
|
1180 degrade compression.
|
|
|
1181 */
|
|
|
1182
|
|
|
1183 ZEXTERN z_off_t ZEXPORT gzseek OF((gzFile file,
|
|
|
1184 z_off_t offset, int whence));
|
|
|
1185 /*
|
|
|
1186 Sets the starting position for the next gzread or gzwrite on the
|
|
|
1187 given compressed file. The offset represents a number of bytes in the
|
|
|
1188 uncompressed data stream. The whence parameter is defined as in lseek(2);
|
|
|
1189 the value SEEK_END is not supported.
|
|
|
1190 If the file is opened for reading, this function is emulated but can be
|
|
|
1191 extremely slow. If the file is opened for writing, only forward seeks are
|
|
|
1192 supported; gzseek then compresses a sequence of zeroes up to the new
|
|
|
1193 starting position.
|
|
|
1194
|
|
|
1195 gzseek returns the resulting offset location as measured in bytes from
|
|
|
1196 the beginning of the uncompressed stream, or -1 in case of error, in
|
|
|
1197 particular if the file is opened for writing and the new starting position
|
|
|
1198 would be before the current position.
|
|
|
1199 */
|
|
|
1200
|
|
|
1201 ZEXTERN int ZEXPORT gzrewind OF((gzFile file));
|
|
|
1202 /*
|
|
|
1203 Rewinds the given file. This function is supported only for reading.
|
|
|
1204
|
|
|
1205 gzrewind(file) is equivalent to (int)gzseek(file, 0L, SEEK_SET)
|
|
|
1206 */
|
|
|
1207
|
|
|
1208 ZEXTERN z_off_t ZEXPORT gztell OF((gzFile file));
|
|
|
1209 /*
|
|
|
1210 Returns the starting position for the next gzread or gzwrite on the
|
|
|
1211 given compressed file. This position represents a number of bytes in the
|
|
|
1212 uncompressed data stream.
|
|
|
1213
|
|
|
1214 gztell(file) is equivalent to gzseek(file, 0L, SEEK_CUR)
|
|
|
1215 */
|
|
|
1216
|
|
|
1217 ZEXTERN int ZEXPORT gzeof OF((gzFile file));
|
|
|
1218 /*
|
|
|
1219 Returns 1 when EOF has previously been detected reading the given
|
|
|
1220 input stream, otherwise zero.
|
|
|
1221 */
|
|
|
1222
|
|
|
1223 ZEXTERN int ZEXPORT gzdirect OF((gzFile file));
|
|
|
1224 /*
|
|
|
1225 Returns 1 if file is being read directly without decompression, otherwise
|
|
|
1226 zero.
|
|
|
1227 */
|
|
|
1228
|
|
|
1229 ZEXTERN int ZEXPORT gzclose OF((gzFile file));
|
|
|
1230 /*
|
|
|
1231 Flushes all pending output if necessary, closes the compressed file
|
|
|
1232 and deallocates all the (de)compression state. The return value is the zlib
|
|
|
1233 error number (see function gzerror below).
|
|
|
1234 */
|
|
|
1235
|
|
|
1236 ZEXTERN const char * ZEXPORT gzerror OF((gzFile file, int *errnum));
|
|
|
1237 /*
|
|
|
1238 Returns the error message for the last error which occurred on the
|
|
|
1239 given compressed file. errnum is set to zlib error number. If an
|
|
|
1240 error occurred in the file system and not in the compression library,
|
|
|
1241 errnum is set to Z_ERRNO and the application may consult errno
|
|
|
1242 to get the exact error code.
|
|
|
1243 */
|
|
|
1244
|
|
|
1245 ZEXTERN void ZEXPORT gzclearerr OF((gzFile file));
|
|
|
1246 /*
|
|
|
1247 Clears the error and end-of-file flags for file. This is analogous to the
|
|
|
1248 clearerr() function in stdio. This is useful for continuing to read a gzip
|
|
|
1249 file that is being written concurrently.
|
|
|
1250 */
|
|
|
1251
|
|
|
1252 /* checksum functions */
|
|
|
1253
|
|
|
1254 /*
|
|
|
1255 These functions are not related to compression but are exported
|
|
|
1256 anyway because they might be useful in applications using the
|
|
|
1257 compression library.
|
|
|
1258 */
|
|
|
1259
|
|
|
1260 ZEXTERN uLong ZEXPORT adler32 OF((uLong adler, const Bytef *buf, uInt len));
|
|
|
1261 /*
|
|
|
1262 Update a running Adler-32 checksum with the bytes buf[0..len-1] and
|
|
|
1263 return the updated checksum. If buf is NULL, this function returns
|
|
|
1264 the required initial value for the checksum.
|
|
|
1265 An Adler-32 checksum is almost as reliable as a CRC32 but can be computed
|
|
|
1266 much faster. Usage example:
|
|
|
1267
|
|
|
1268 uLong adler = adler32(0L, Z_NULL, 0);
|
|
|
1269
|
|
|
1270 while (read_buffer(buffer, length) != EOF) {
|
|
|
1271 adler = adler32(adler, buffer, length);
|
|
|
1272 }
|
|
|
1273 if (adler != original_adler) error();
|
|
|
1274 */
|
|
|
1275
|
|
|
1276 ZEXTERN uLong ZEXPORT adler32_combine OF((uLong adler1, uLong adler2,
|
|
|
1277 z_off_t len2));
|
|
|
1278 /*
|
|
|
1279 Combine two Adler-32 checksums into one. For two sequences of bytes, seq1
|
|
|
1280 and seq2 with lengths len1 and len2, Adler-32 checksums were calculated for
|
|
|
1281 each, adler1 and adler2. adler32_combine() returns the Adler-32 checksum of
|
|
|
1282 seq1 and seq2 concatenated, requiring only adler1, adler2, and len2.
|
|
|
1283 */
|
|
|
1284
|
|
|
1285 ZEXTERN uLong ZEXPORT crc32 OF((uLong crc, const Bytef *buf, uInt len));
|
|
|
1286 /*
|
|
|
1287 Update a running CRC-32 with the bytes buf[0..len-1] and return the
|
|
|
1288 updated CRC-32. If buf is NULL, this function returns the required initial
|
|
|
1289 value for the for the crc. Pre- and post-conditioning (one's complement) is
|
|
|
1290 performed within this function so it shouldn't be done by the application.
|
|
|
1291 Usage example:
|
|
|
1292
|
|
|
1293 uLong crc = crc32(0L, Z_NULL, 0);
|
|
|
1294
|
|
|
1295 while (read_buffer(buffer, length) != EOF) {
|
|
|
1296 crc = crc32(crc, buffer, length);
|
|
|
1297 }
|
|
|
1298 if (crc != original_crc) error();
|
|
|
1299 */
|
|
|
1300
|
|
|
1301 ZEXTERN uLong ZEXPORT crc32_combine OF((uLong crc1, uLong crc2, z_off_t len2));
|
|
|
1302
|
|
|
1303 /*
|
|
|
1304 Combine two CRC-32 check values into one. For two sequences of bytes,
|
|
|
1305 seq1 and seq2 with lengths len1 and len2, CRC-32 check values were
|
|
|
1306 calculated for each, crc1 and crc2. crc32_combine() returns the CRC-32
|
|
|
1307 check value of seq1 and seq2 concatenated, requiring only crc1, crc2, and
|
|
|
1308 len2.
|
|
|
1309 */
|
|
|
1310
|
|
|
1311
|
|
|
1312 /* various hacks, don't look :) */
|
|
|
1313
|
|
|
1314 /* deflateInit and inflateInit are macros to allow checking the zlib version
|
|
|
1315 * and the compiler's view of z_stream:
|
|
|
1316 */
|
|
|
1317 ZEXTERN int ZEXPORT deflateInit_ OF((z_streamp strm, int level,
|
|
|
1318 const char *version, int stream_size));
|
|
|
1319 ZEXTERN int ZEXPORT inflateInit_ OF((z_streamp strm,
|
|
|
1320 const char *version, int stream_size));
|
|
|
1321 ZEXTERN int ZEXPORT deflateInit2_ OF((z_streamp strm, int level, int method,
|
|
|
1322 int windowBits, int memLevel,
|
|
|
1323 int strategy, const char *version,
|
|
|
1324 int stream_size));
|
|
|
1325 ZEXTERN int ZEXPORT inflateInit2_ OF((z_streamp strm, int windowBits,
|
|
|
1326 const char *version, int stream_size));
|
|
|
1327 ZEXTERN int ZEXPORT inflateBackInit_ OF((z_streamp strm, int windowBits,
|
|
|
1328 unsigned char FAR *window,
|
|
|
1329 const char *version,
|
|
|
1330 int stream_size));
|
|
|
1331 #define deflateInit(strm, level) \
|
|
|
1332 deflateInit_((strm), (level), ZLIB_VERSION, sizeof(z_stream))
|
|
|
1333 #define inflateInit(strm) \
|
|
|
1334 inflateInit_((strm), ZLIB_VERSION, sizeof(z_stream))
|
|
|
1335 #define deflateInit2(strm, level, method, windowBits, memLevel, strategy) \
|
|
|
1336 deflateInit2_((strm),(level),(method),(windowBits),(memLevel),\
|
|
|
1337 (strategy), ZLIB_VERSION, sizeof(z_stream))
|
|
|
1338 #define inflateInit2(strm, windowBits) \
|
|
|
1339 inflateInit2_((strm), (windowBits), ZLIB_VERSION, sizeof(z_stream))
|
|
|
1340 #define inflateBackInit(strm, windowBits, window) \
|
|
|
1341 inflateBackInit_((strm), (windowBits), (window), \
|
|
|
1342 ZLIB_VERSION, sizeof(z_stream))
|
|
|
1343
|
|
|
1344
|
|
|
1345 #if !defined(ZUTIL_H) && !defined(NO_DUMMY_DECL)
|
|
|
1346 struct internal_state {int dummy;}; /* hack for buggy compilers */
|
|
|
1347 #endif
|
|
|
1348
|
|
|
1349 ZEXTERN const char * ZEXPORT zError OF((int));
|
|
|
1350 ZEXTERN int ZEXPORT inflateSyncPoint OF((z_streamp z));
|
|
|
1351 ZEXTERN const uLongf * ZEXPORT get_crc_table OF((void));
|
|
|
1352
|
|
|
1353 #ifdef __cplusplus
|
|
|
1354 }
|
|
|
1355 #endif
|
|
|
1356
|
|
|
1357 #endif /* ZLIB_H */
|
