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diff --git a/doc/api-documentation/html/zlib.h-source.html b/doc/api-documentation/html/zlib.h-source.html new file mode 100644 index 0000000..b436ad9 --- /dev/null +++ b/doc/api-documentation/html/zlib.h-source.html @@ -0,0 +1,908 @@ +<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"> +<html><head><meta name="robots" content="noindex"> +<title>zlib.h Source File</title> +<link href="doxygen.css" rel="stylesheet" type="text/css"> +</head><body bgcolor="#ffffff"> +<!-- Generated by Doxygen 1.1.5 on Thu May 24 19:50:26 2001 --> +<center> +<a class="qindex" href="index.html">Main Page</a> <a class="qindex" href="hierarchy.html">Class Hierarchy</a> <a class="qindex" href="classes.html">Alphabetical List</a> <a class="qindex" href="annotated.html">Compound List</a> <a class="qindex" href="files.html">File List</a> <a class="qindex" href="functions.html">Compound Members</a> </center> +<hr><h1>zlib.h</h1><div class="fragment"><pre>00001 <font class="comment">/* zlib.h -- interface of the 'zlib' general purpose compression library +</font>00002 <font class="comment"> version 1.1.3, July 9th, 1998 +</font>00003 <font class="comment"> +</font>00004 <font class="comment"> Copyright (C) 1995-1998 Jean-loup Gailly and Mark Adler +</font>00005 <font class="comment"> +</font>00006 <font class="comment"> This software is provided 'as-is', without any express or implied +</font>00007 <font class="comment"> warranty. In no event will the authors be held liable for any damages +</font>00008 <font class="comment"> arising from the use of this software. +</font>00009 <font class="comment"> +</font>00010 <font class="comment"> Permission is granted to anyone to use this software for any purpose, +</font>00011 <font class="comment"> including commercial applications, and to alter it and redistribute it +</font>00012 <font class="comment"> freely, subject to the following restrictions: +</font>00013 <font class="comment"> +</font>00014 <font class="comment"> 1. The origin of this software must not be misrepresented; you must not +</font>00015 <font class="comment"> claim that you wrote the original software. If you use this software +</font>00016 <font class="comment"> in a product, an acknowledgment in the product documentation would be +</font>00017 <font class="comment"> appreciated but is not required. +</font>00018 <font class="comment"> 2. Altered source versions must be plainly marked as such, and must not be +</font>00019 <font class="comment"> misrepresented as being the original software. +</font>00020 <font class="comment"> 3. This notice may not be removed or altered from any source distribution. +</font>00021 <font class="comment"> +</font>00022 <font class="comment"> Jean-loup Gailly Mark Adler +</font>00023 <font class="comment"> jloup@gzip.org madler@alumni.caltech.edu +</font>00024 <font class="comment"> +</font>00025 <font class="comment"> +</font>00026 <font class="comment"> The data format used by the zlib library is described by RFCs (Request for +</font>00027 <font class="comment"> Comments) 1950 to 1952 in the files ftp://ds.internic.net/rfc/rfc1950.txt +</font>00028 <font class="comment"> (zlib format), rfc1951.txt (deflate format) and rfc1952.txt (gzip format). +</font>00029 <font class="comment">*/</font> +00030 +00031 <font class="preprocessor">#ifndef _ZLIB_H +</font>00032 <font class="preprocessor"></font><font class="preprocessor">#define _ZLIB_H +</font>00033 <font class="preprocessor"></font> +00034 <font class="preprocessor">#include "zconf.h"</font> +00035 +00036 <font class="preprocessor">#ifdef __cplusplus +</font>00037 <font class="preprocessor"></font><font class="keyword">extern</font> <font class="stringliteral">"C"</font> { +00038 <font class="preprocessor">#endif +</font>00039 <font class="preprocessor"></font> +00040 <font class="preprocessor">#define ZLIB_VERSION "1.1.3" +</font>00041 <font class="preprocessor"></font> +00042 <font class="comment">/* +</font>00043 <font class="comment"> The 'zlib' compression library provides in-memory compression and +</font>00044 <font class="comment"> decompression functions, including integrity checks of the uncompressed +</font>00045 <font class="comment"> data. This version of the library supports only one compression method +</font>00046 <font class="comment"> (deflation) but other algorithms will be added later and will have the same +</font>00047 <font class="comment"> stream interface. +</font>00048 <font class="comment"> +</font>00049 <font class="comment"> Compression can be done in a single step if the buffers are large +</font>00050 <font class="comment"> enough (for example if an input file is mmap'ed), or can be done by +</font>00051 <font class="comment"> repeated calls of the compression function. In the latter case, the +</font>00052 <font class="comment"> application must provide more input and/or consume the output +</font>00053 <font class="comment"> (providing more output space) before each call. +</font>00054 <font class="comment"> +</font>00055 <font class="comment"> The library also supports reading and writing files in gzip (.gz) format +</font>00056 <font class="comment"> with an interface similar to that of stdio. +</font>00057 <font class="comment"> +</font>00058 <font class="comment"> The library does not install any signal handler. The decoder checks +</font>00059 <font class="comment"> the consistency of the compressed data, so the library should never +</font>00060 <font class="comment"> crash even in case of corrupted input. +</font>00061 <font class="comment">*/</font> +00062 +00063 <font class="keyword">typedef</font> voidpf (*alloc_func) OF((voidpf opaque, uInt items, uInt size)); +00064 <font class="keyword">typedef</font> void (*free_func) OF((voidpf opaque, voidpf address)); +00065 +00066 <font class="keyword">struct </font>internal_state; +00067 +00068 <font class="keyword">typedef</font> <font class="keyword">struct </font>z_stream_s { +00069 Bytef *next_in; <font class="comment">/* next input byte */</font> +00070 uInt avail_in; <font class="comment">/* number of bytes available at next_in */</font> +00071 uLong total_in; <font class="comment">/* total nb of input bytes read so far */</font> +00072 +00073 Bytef *next_out; <font class="comment">/* next output byte should be put there */</font> +00074 uInt avail_out; <font class="comment">/* remaining free space at next_out */</font> +00075 uLong total_out; <font class="comment">/* total nb of bytes output so far */</font> +00076 +00077 <font class="keywordtype">char</font> *msg; <font class="comment">/* last error message, NULL if no error */</font> +00078 <font class="keyword">struct </font>internal_state FAR *state; <font class="comment">/* not visible by applications */</font> +00079 +00080 alloc_func zalloc; <font class="comment">/* used to allocate the internal state */</font> +00081 free_func zfree; <font class="comment">/* used to free the internal state */</font> +00082 voidpf opaque; <font class="comment">/* private data object passed to zalloc and zfree */</font> +00083 +00084 <font class="keywordtype">int</font> data_type; <font class="comment">/* best guess about the data type: ascii or binary */</font> +00085 uLong adler; <font class="comment">/* adler32 value of the uncompressed data */</font> +00086 uLong reserved; <font class="comment">/* reserved for future use */</font> +00087 } z_stream; +00088 +00089 <font class="keyword">typedef</font> z_stream FAR *z_streamp; +00090 +00091 <font class="comment">/* +</font>00092 <font class="comment"> The application must update next_in and avail_in when avail_in has +</font>00093 <font class="comment"> dropped to zero. It must update next_out and avail_out when avail_out +</font>00094 <font class="comment"> has dropped to zero. The application must initialize zalloc, zfree and +</font>00095 <font class="comment"> opaque before calling the init function. All other fields are set by the +</font>00096 <font class="comment"> compression library and must not be updated by the application. +</font>00097 <font class="comment"> +</font>00098 <font class="comment"> The opaque value provided by the application will be passed as the first +</font>00099 <font class="comment"> parameter for calls of zalloc and zfree. This can be useful for custom +</font>00100 <font class="comment"> memory management. The compression library attaches no meaning to the +</font>00101 <font class="comment"> opaque value. +</font>00102 <font class="comment"> +</font>00103 <font class="comment"> zalloc must return Z_NULL if there is not enough memory for the object. +</font>00104 <font class="comment"> If zlib is used in a multi-threaded application, zalloc and zfree must be +</font>00105 <font class="comment"> thread safe. +</font>00106 <font class="comment"> +</font>00107 <font class="comment"> On 16-bit systems, the functions zalloc and zfree must be able to allocate +</font>00108 <font class="comment"> exactly 65536 bytes, but will not be required to allocate more than this +</font>00109 <font class="comment"> if the symbol MAXSEG_64K is defined (see zconf.h). WARNING: On MSDOS, +</font>00110 <font class="comment"> pointers returned by zalloc for objects of exactly 65536 bytes *must* +</font>00111 <font class="comment"> have their offset normalized to zero. The default allocation function +</font>00112 <font class="comment"> provided by this library ensures this (see zutil.c). To reduce memory +</font>00113 <font class="comment"> requirements and avoid any allocation of 64K objects, at the expense of +</font>00114 <font class="comment"> compression ratio, compile the library with -DMAX_WBITS=14 (see zconf.h). +</font>00115 <font class="comment"> +</font>00116 <font class="comment"> The fields total_in and total_out can be used for statistics or +</font>00117 <font class="comment"> progress reports. After compression, total_in holds the total size of +</font>00118 <font class="comment"> the uncompressed data and may be saved for use in the decompressor +</font>00119 <font class="comment"> (particularly if the decompressor wants to decompress everything in +</font>00120 <font class="comment"> a single step). +</font>00121 <font class="comment">*/</font> +00122 +00123 <font class="comment">/* constants */</font> +00124 +00125 <font class="preprocessor">#define Z_NO_FLUSH 0 +</font>00126 <font class="preprocessor"></font><font class="preprocessor">#define Z_PARTIAL_FLUSH 1 </font><font class="comment">/* will be removed, use Z_SYNC_FLUSH instead */</font> +00127 <font class="preprocessor">#define Z_SYNC_FLUSH 2 +</font>00128 <font class="preprocessor"></font><font class="preprocessor">#define Z_FULL_FLUSH 3 +</font>00129 <font class="preprocessor"></font><font class="preprocessor">#define Z_FINISH 4 +</font>00130 <font class="preprocessor"></font><font class="comment">/* Allowed flush values; see deflate() below for details */</font> +00131 +00132 <font class="preprocessor">#define Z_OK 0 +</font>00133 <font class="preprocessor"></font><font class="preprocessor">#define Z_STREAM_END 1 +</font>00134 <font class="preprocessor"></font><font class="preprocessor">#define Z_NEED_DICT 2 +</font>00135 <font class="preprocessor"></font><font class="preprocessor">#define Z_ERRNO (-1) +</font>00136 <font class="preprocessor"></font><font class="preprocessor">#define Z_STREAM_ERROR (-2) +</font>00137 <font class="preprocessor"></font><font class="preprocessor">#define Z_DATA_ERROR (-3) +</font>00138 <font class="preprocessor"></font><font class="preprocessor">#define Z_MEM_ERROR (-4) +</font>00139 <font class="preprocessor"></font><font class="preprocessor">#define Z_BUF_ERROR (-5) +</font>00140 <font class="preprocessor"></font><font class="preprocessor">#define Z_VERSION_ERROR (-6) +</font>00141 <font class="preprocessor"></font><font class="comment">/* Return codes for the compression/decompression functions. Negative +</font>00142 <font class="comment"> * values are errors, positive values are used for special but normal events. +</font>00143 <font class="comment"> */</font> +00144 +00145 <font class="preprocessor">#define Z_NO_COMPRESSION 0 +</font>00146 <font class="preprocessor"></font><font class="preprocessor">#define Z_BEST_SPEED 1 +</font>00147 <font class="preprocessor"></font><font class="preprocessor">#define Z_BEST_COMPRESSION 9 +</font>00148 <font class="preprocessor"></font><font class="preprocessor">#define Z_DEFAULT_COMPRESSION (-1) +</font>00149 <font class="preprocessor"></font><font class="comment">/* compression levels */</font> +00150 +00151 <font class="preprocessor">#define Z_FILTERED 1 +</font>00152 <font class="preprocessor"></font><font class="preprocessor">#define Z_HUFFMAN_ONLY 2 +</font>00153 <font class="preprocessor"></font><font class="preprocessor">#define Z_DEFAULT_STRATEGY 0 +</font>00154 <font class="preprocessor"></font><font class="comment">/* compression strategy; see deflateInit2() below for details */</font> +00155 +00156 <font class="preprocessor">#define Z_BINARY 0 +</font>00157 <font class="preprocessor"></font><font class="preprocessor">#define Z_ASCII 1 +</font>00158 <font class="preprocessor"></font><font class="preprocessor">#define Z_UNKNOWN 2 +</font>00159 <font class="preprocessor"></font><font class="comment">/* Possible values of the data_type field */</font> +00160 +00161 <font class="preprocessor">#define Z_DEFLATED 8 +</font>00162 <font class="preprocessor"></font><font class="comment">/* The deflate compression method (the only one supported in this version) */</font> +00163 +00164 <font class="preprocessor">#define Z_NULL 0 </font><font class="comment">/* for initializing zalloc, zfree, opaque */</font> +00165 +00166 <font class="preprocessor">#define zlib_version zlibVersion() +</font>00167 <font class="preprocessor"></font><font class="comment">/* for compatibility with versions < 1.0.2 */</font> +00168 +00169 <font class="comment">/* basic functions */</font> +00170 +00171 ZEXTERN <font class="keyword">const</font> <font class="keywordtype">char</font> * ZEXPORT zlibVersion OF((<font class="keywordtype">void</font>)); +00172 <font class="comment">/* The application can compare zlibVersion and ZLIB_VERSION for consistency. +</font>00173 <font class="comment"> If the first character differs, the library code actually used is +</font>00174 <font class="comment"> not compatible with the zlib.h header file used by the application. +</font>00175 <font class="comment"> This check is automatically made by deflateInit and inflateInit. +</font>00176 <font class="comment"> */</font> +00177 +00178 <font class="comment">/* +</font>00179 <font class="comment">ZEXTERN int ZEXPORT deflateInit OF((z_streamp strm, int level)); +</font>00180 <font class="comment"> +</font>00181 <font class="comment"> Initializes the internal stream state for compression. The fields +</font>00182 <font class="comment"> zalloc, zfree and opaque must be initialized before by the caller. +</font>00183 <font class="comment"> If zalloc and zfree are set to Z_NULL, deflateInit updates them to +</font>00184 <font class="comment"> use default allocation functions. +</font>00185 <font class="comment"> +</font>00186 <font class="comment"> The compression level must be Z_DEFAULT_COMPRESSION, or between 0 and 9: +</font>00187 <font class="comment"> 1 gives best speed, 9 gives best compression, 0 gives no compression at +</font>00188 <font class="comment"> all (the input data is simply copied a block at a time). +</font>00189 <font class="comment"> Z_DEFAULT_COMPRESSION requests a default compromise between speed and +</font>00190 <font class="comment"> compression (currently equivalent to level 6). +</font>00191 <font class="comment"> +</font>00192 <font class="comment"> deflateInit returns Z_OK if success, Z_MEM_ERROR if there was not +</font>00193 <font class="comment"> enough memory, Z_STREAM_ERROR if level is not a valid compression level, +</font>00194 <font class="comment"> Z_VERSION_ERROR if the zlib library version (zlib_version) is incompatible +</font>00195 <font class="comment"> with the version assumed by the caller (ZLIB_VERSION). +</font>00196 <font class="comment"> msg is set to null if there is no error message. deflateInit does not +</font>00197 <font class="comment"> perform any compression: this will be done by deflate(). +</font>00198 <font class="comment">*/</font> +00199 +00200 +00201 ZEXTERN <font class="keywordtype">int</font> ZEXPORT deflate OF((z_streamp strm, <font class="keywordtype">int</font> flush)); +00202 <font class="comment">/* +</font>00203 <font class="comment"> deflate compresses as much data as possible, and stops when the input +</font>00204 <font class="comment"> buffer becomes empty or the output buffer becomes full. It may introduce some +</font>00205 <font class="comment"> output latency (reading input without producing any output) except when +</font>00206 <font class="comment"> forced to flush. +</font>00207 <font class="comment"> +</font>00208 <font class="comment"> The detailed semantics are as follows. deflate performs one or both of the +</font>00209 <font class="comment"> following actions: +</font>00210 <font class="comment"> +</font>00211 <font class="comment"> - Compress more input starting at next_in and update next_in and avail_in +</font>00212 <font class="comment"> accordingly. If not all input can be processed (because there is not +</font>00213 <font class="comment"> enough room in the output buffer), next_in and avail_in are updated and +</font>00214 <font class="comment"> processing will resume at this point for the next call of deflate(). +</font>00215 <font class="comment"> +</font>00216 <font class="comment"> - Provide more output starting at next_out and update next_out and avail_out +</font>00217 <font class="comment"> accordingly. This action is forced if the parameter flush is non zero. +</font>00218 <font class="comment"> Forcing flush frequently degrades the compression ratio, so this parameter +</font>00219 <font class="comment"> should be set only when necessary (in interactive applications). +</font>00220 <font class="comment"> Some output may be provided even if flush is not set. +</font>00221 <font class="comment"> +</font>00222 <font class="comment"> Before the call of deflate(), the application should ensure that at least +</font>00223 <font class="comment"> one of the actions is possible, by providing more input and/or consuming +</font>00224 <font class="comment"> more output, and updating avail_in or avail_out accordingly; avail_out +</font>00225 <font class="comment"> should never be zero before the call. The application can consume the +</font>00226 <font class="comment"> compressed output when it wants, for example when the output buffer is full +</font>00227 <font class="comment"> (avail_out == 0), or after each call of deflate(). If deflate returns Z_OK +</font>00228 <font class="comment"> and with zero avail_out, it must be called again after making room in the +</font>00229 <font class="comment"> output buffer because there might be more output pending. +</font>00230 <font class="comment"> +</font>00231 <font class="comment"> If the parameter flush is set to Z_SYNC_FLUSH, all pending output is +</font>00232 <font class="comment"> flushed to the output buffer and the output is aligned on a byte boundary, so +</font>00233 <font class="comment"> that the decompressor can get all input data available so far. (In particular +</font>00234 <font class="comment"> avail_in is zero after the call if enough output space has been provided +</font>00235 <font class="comment"> before the call.) Flushing may degrade compression for some compression +</font>00236 <font class="comment"> algorithms and so it should be used only when necessary. +</font>00237 <font class="comment"> +</font>00238 <font class="comment"> If flush is set to Z_FULL_FLUSH, all output is flushed as with +</font>00239 <font class="comment"> Z_SYNC_FLUSH, and the compression state is reset so that decompression can +</font>00240 <font class="comment"> restart from this point if previous compressed data has been damaged or if +</font>00241 <font class="comment"> random access is desired. Using Z_FULL_FLUSH too often can seriously degrade +</font>00242 <font class="comment"> the compression. +</font>00243 <font class="comment"> +</font>00244 <font class="comment"> If deflate returns with avail_out == 0, this function must be called again +</font>00245 <font class="comment"> with the same value of the flush parameter and more output space (updated +</font>00246 <font class="comment"> avail_out), until the flush is complete (deflate returns with non-zero +</font>00247 <font class="comment"> avail_out). +</font>00248 <font class="comment"> +</font>00249 <font class="comment"> If the parameter flush is set to Z_FINISH, pending input is processed, +</font>00250 <font class="comment"> pending output is flushed and deflate returns with Z_STREAM_END if there +</font>00251 <font class="comment"> was enough output space; if deflate returns with Z_OK, this function must be +</font>00252 <font class="comment"> called again with Z_FINISH and more output space (updated avail_out) but no +</font>00253 <font class="comment"> more input data, until it returns with Z_STREAM_END or an error. After +</font>00254 <font class="comment"> deflate has returned Z_STREAM_END, the only possible operations on the +</font>00255 <font class="comment"> stream are deflateReset or deflateEnd. +</font>00256 <font class="comment"> +</font>00257 <font class="comment"> Z_FINISH can be used immediately after deflateInit if all the compression +</font>00258 <font class="comment"> is to be done in a single step. In this case, avail_out must be at least +</font>00259 <font class="comment"> 0.1% larger than avail_in plus 12 bytes. If deflate does not return +</font>00260 <font class="comment"> Z_STREAM_END, then it must be called again as described above. +</font>00261 <font class="comment"> +</font>00262 <font class="comment"> deflate() sets strm->adler to the adler32 checksum of all input read +</font>00263 <font class="comment"> so far (that is, total_in bytes). +</font>00264 <font class="comment"> +</font>00265 <font class="comment"> deflate() may update data_type if it can make a good guess about +</font>00266 <font class="comment"> the input data type (Z_ASCII or Z_BINARY). In doubt, the data is considered +</font>00267 <font class="comment"> binary. This field is only for information purposes and does not affect +</font>00268 <font class="comment"> the compression algorithm in any manner. +</font>00269 <font class="comment"> +</font>00270 <font class="comment"> deflate() returns Z_OK if some progress has been made (more input +</font>00271 <font class="comment"> processed or more output produced), Z_STREAM_END if all input has been +</font>00272 <font class="comment"> consumed and all output has been produced (only when flush is set to +</font>00273 <font class="comment"> Z_FINISH), Z_STREAM_ERROR if the stream state was inconsistent (for example +</font>00274 <font class="comment"> if next_in or next_out was NULL), Z_BUF_ERROR if no progress is possible +</font>00275 <font class="comment"> (for example avail_in or avail_out was zero). +</font>00276 <font class="comment">*/</font> +00277 +00278 +00279 ZEXTERN <font class="keywordtype">int</font> ZEXPORT deflateEnd OF((z_streamp strm)); +00280 <font class="comment">/* +</font>00281 <font class="comment"> All dynamically allocated data structures for this stream are freed. +</font>00282 <font class="comment"> This function discards any unprocessed input and does not flush any +</font>00283 <font class="comment"> pending output. +</font>00284 <font class="comment"> +</font>00285 <font class="comment"> deflateEnd returns Z_OK if success, Z_STREAM_ERROR if the +</font>00286 <font class="comment"> stream state was inconsistent, Z_DATA_ERROR if the stream was freed +</font>00287 <font class="comment"> prematurely (some input or output was discarded). In the error case, +</font>00288 <font class="comment"> msg may be set but then points to a static string (which must not be +</font>00289 <font class="comment"> deallocated). +</font>00290 <font class="comment">*/</font> +00291 +00292 +00293 <font class="comment">/* +</font>00294 <font class="comment">ZEXTERN int ZEXPORT inflateInit OF((z_streamp strm)); +</font>00295 <font class="comment"> +</font>00296 <font class="comment"> Initializes the internal stream state for decompression. The fields +</font>00297 <font class="comment"> next_in, avail_in, zalloc, zfree and opaque must be initialized before by +</font>00298 <font class="comment"> the caller. If next_in is not Z_NULL and avail_in is large enough (the exact +</font>00299 <font class="comment"> value depends on the compression method), inflateInit determines the +</font>00300 <font class="comment"> compression method from the zlib header and allocates all data structures +</font>00301 <font class="comment"> accordingly; otherwise the allocation will be deferred to the first call of +</font>00302 <font class="comment"> inflate. If zalloc and zfree are set to Z_NULL, inflateInit updates them to +</font>00303 <font class="comment"> use default allocation functions. +</font>00304 <font class="comment"> +</font>00305 <font class="comment"> inflateInit returns Z_OK if success, Z_MEM_ERROR if there was not enough +</font>00306 <font class="comment"> memory, Z_VERSION_ERROR if the zlib library version is incompatible with the +</font>00307 <font class="comment"> version assumed by the caller. msg is set to null if there is no error +</font>00308 <font class="comment"> message. inflateInit does not perform any decompression apart from reading +</font>00309 <font class="comment"> the zlib header if present: this will be done by inflate(). (So next_in and +</font>00310 <font class="comment"> avail_in may be modified, but next_out and avail_out are unchanged.) +</font>00311 <font class="comment">*/</font> +00312 +00313 +00314 ZEXTERN <font class="keywordtype">int</font> ZEXPORT inflate OF((z_streamp strm, <font class="keywordtype">int</font> flush)); +00315 <font class="comment">/* +</font>00316 <font class="comment"> inflate decompresses as much data as possible, and stops when the input +</font>00317 <font class="comment"> buffer becomes empty or the output buffer becomes full. It may some +</font>00318 <font class="comment"> introduce some output latency (reading input without producing any output) +</font>00319 <font class="comment"> except when forced to flush. +</font>00320 <font class="comment"> +</font>00321 <font class="comment"> The detailed semantics are as follows. inflate performs one or both of the +</font>00322 <font class="comment"> following actions: +</font>00323 <font class="comment"> +</font>00324 <font class="comment"> - Decompress more input starting at next_in and update next_in and avail_in +</font>00325 <font class="comment"> accordingly. If not all input can be processed (because there is not +</font>00326 <font class="comment"> enough room in the output buffer), next_in is updated and processing +</font>00327 <font class="comment"> will resume at this point for the next call of inflate(). +</font>00328 <font class="comment"> +</font>00329 <font class="comment"> - Provide more output starting at next_out and update next_out and avail_out +</font>00330 <font class="comment"> accordingly. inflate() provides as much output as possible, until there +</font>00331 <font class="comment"> is no more input data or no more space in the output buffer (see below +</font>00332 <font class="comment"> about the flush parameter). +</font>00333 <font class="comment"> +</font>00334 <font class="comment"> Before the call of inflate(), the application should ensure that at least +</font>00335 <font class="comment"> one of the actions is possible, by providing more input and/or consuming +</font>00336 <font class="comment"> more output, and updating the next_* and avail_* values accordingly. +</font>00337 <font class="comment"> The application can consume the uncompressed output when it wants, for +</font>00338 <font class="comment"> example when the output buffer is full (avail_out == 0), or after each +</font>00339 <font class="comment"> call of inflate(). If inflate returns Z_OK and with zero avail_out, it +</font>00340 <font class="comment"> must be called again after making room in the output buffer because there +</font>00341 <font class="comment"> might be more output pending. +</font>00342 <font class="comment"> +</font>00343 <font class="comment"> If the parameter flush is set to Z_SYNC_FLUSH, inflate flushes as much +</font>00344 <font class="comment"> output as possible to the output buffer. The flushing behavior of inflate is +</font>00345 <font class="comment"> not specified for values of the flush parameter other than Z_SYNC_FLUSH +</font>00346 <font class="comment"> and Z_FINISH, but the current implementation actually flushes as much output +</font>00347 <font class="comment"> as possible anyway. +</font>00348 <font class="comment"> +</font>00349 <font class="comment"> inflate() should normally be called until it returns Z_STREAM_END or an +</font>00350 <font class="comment"> error. However if all decompression is to be performed in a single step +</font>00351 <font class="comment"> (a single call of inflate), the parameter flush should be set to +</font>00352 <font class="comment"> Z_FINISH. In this case all pending input is processed and all pending +</font>00353 <font class="comment"> output is flushed; avail_out must be large enough to hold all the +</font>00354 <font class="comment"> uncompressed data. (The size of the uncompressed data may have been saved +</font>00355 <font class="comment"> by the compressor for this purpose.) The next operation on this stream must +</font>00356 <font class="comment"> be inflateEnd to deallocate the decompression state. The use of Z_FINISH +</font>00357 <font class="comment"> is never required, but can be used to inform inflate that a faster routine +</font>00358 <font class="comment"> may be used for the single inflate() call. +</font>00359 <font class="comment"> +</font>00360 <font class="comment"> If a preset dictionary is needed at this point (see inflateSetDictionary +</font>00361 <font class="comment"> below), inflate sets strm-adler to the adler32 checksum of the +</font>00362 <font class="comment"> dictionary chosen by the compressor and returns Z_NEED_DICT; otherwise +</font>00363 <font class="comment"> it sets strm->adler to the adler32 checksum of all output produced +</font>00364 <font class="comment"> so far (that is, total_out bytes) and returns Z_OK, Z_STREAM_END or +</font>00365 <font class="comment"> an error code as described below. At the end of the stream, inflate() +</font>00366 <font class="comment"> checks that its computed adler32 checksum is equal to that saved by the +</font>00367 <font class="comment"> compressor and returns Z_STREAM_END only if the checksum is correct. +</font>00368 <font class="comment"> +</font>00369 <font class="comment"> inflate() returns Z_OK if some progress has been made (more input processed +</font>00370 <font class="comment"> or more output produced), Z_STREAM_END if the end of the compressed data has +</font>00371 <font class="comment"> been reached and all uncompressed output has been produced, Z_NEED_DICT if a +</font>00372 <font class="comment"> preset dictionary is needed at this point, Z_DATA_ERROR if the input data was +</font>00373 <font class="comment"> corrupted (input stream not conforming to the zlib format or incorrect +</font>00374 <font class="comment"> adler32 checksum), Z_STREAM_ERROR if the stream structure was inconsistent +</font>00375 <font class="comment"> (for example if next_in or next_out was NULL), Z_MEM_ERROR if there was not +</font>00376 <font class="comment"> enough memory, Z_BUF_ERROR if no progress is possible or if there was not +</font>00377 <font class="comment"> enough room in the output buffer when Z_FINISH is used. In the Z_DATA_ERROR +</font>00378 <font class="comment"> case, the application may then call inflateSync to look for a good +</font>00379 <font class="comment"> compression block. +</font>00380 <font class="comment">*/</font> +00381 +00382 +00383 ZEXTERN <font class="keywordtype">int</font> ZEXPORT inflateEnd OF((z_streamp strm)); +00384 <font class="comment">/* +</font>00385 <font class="comment"> All dynamically allocated data structures for this stream are freed. +</font>00386 <font class="comment"> This function discards any unprocessed input and does not flush any +</font>00387 <font class="comment"> pending output. +</font>00388 <font class="comment"> +</font>00389 <font class="comment"> inflateEnd returns Z_OK if success, Z_STREAM_ERROR if the stream state +</font>00390 <font class="comment"> was inconsistent. In the error case, msg may be set but then points to a +</font>00391 <font class="comment"> static string (which must not be deallocated). +</font>00392 <font class="comment">*/</font> +00393 +00394 <font class="comment">/* Advanced functions */</font> +00395 +00396 <font class="comment">/* +</font>00397 <font class="comment"> The following functions are needed only in some special applications. +</font>00398 <font class="comment">*/</font> +00399 +00400 <font class="comment">/* +</font>00401 <font class="comment">ZEXTERN int ZEXPORT deflateInit2 OF((z_streamp strm, +</font>00402 <font class="comment"> int level, +</font>00403 <font class="comment"> int method, +</font>00404 <font class="comment"> int windowBits, +</font>00405 <font class="comment"> int memLevel, +</font>00406 <font class="comment"> int strategy)); +</font>00407 <font class="comment"> +</font>00408 <font class="comment"> This is another version of deflateInit with more compression options. The +</font>00409 <font class="comment"> fields next_in, zalloc, zfree and opaque must be initialized before by +</font>00410 <font class="comment"> the caller. +</font>00411 <font class="comment"> +</font>00412 <font class="comment"> The method parameter is the compression method. It must be Z_DEFLATED in +</font>00413 <font class="comment"> this version of the library. +</font>00414 <font class="comment"> +</font>00415 <font class="comment"> The windowBits parameter is the base two logarithm of the window size +</font>00416 <font class="comment"> (the size of the history buffer). It should be in the range 8..15 for this +</font>00417 <font class="comment"> version of the library. Larger values of this parameter result in better +</font>00418 <font class="comment"> compression at the expense of memory usage. The default value is 15 if +</font>00419 <font class="comment"> deflateInit is used instead. +</font>00420 <font class="comment"> +</font>00421 <font class="comment"> The memLevel parameter specifies how much memory should be allocated +</font>00422 <font class="comment"> for the internal compression state. memLevel=1 uses minimum memory but +</font>00423 <font class="comment"> is slow and reduces compression ratio; memLevel=9 uses maximum memory +</font>00424 <font class="comment"> for optimal speed. The default value is 8. See zconf.h for total memory +</font>00425 <font class="comment"> usage as a function of windowBits and memLevel. +</font>00426 <font class="comment"> +</font>00427 <font class="comment"> The strategy parameter is used to tune the compression algorithm. Use the +</font>00428 <font class="comment"> value Z_DEFAULT_STRATEGY for normal data, Z_FILTERED for data produced by a +</font>00429 <font class="comment"> filter (or predictor), or Z_HUFFMAN_ONLY to force Huffman encoding only (no +</font>00430 <font class="comment"> string match). Filtered data consists mostly of small values with a +</font>00431 <font class="comment"> somewhat random distribution. In this case, the compression algorithm is +</font>00432 <font class="comment"> tuned to compress them better. The effect of Z_FILTERED is to force more +</font>00433 <font class="comment"> Huffman coding and less string matching; it is somewhat intermediate +</font>00434 <font class="comment"> between Z_DEFAULT and Z_HUFFMAN_ONLY. The strategy parameter only affects +</font>00435 <font class="comment"> the compression ratio but not the correctness of the compressed output even +</font>00436 <font class="comment"> if it is not set appropriately. +</font>00437 <font class="comment"> +</font>00438 <font class="comment"> deflateInit2 returns Z_OK if success, Z_MEM_ERROR if there was not enough +</font>00439 <font class="comment"> memory, Z_STREAM_ERROR if a parameter is invalid (such as an invalid +</font>00440 <font class="comment"> method). msg is set to null if there is no error message. deflateInit2 does +</font>00441 <font class="comment"> not perform any compression: this will be done by deflate(). +</font>00442 <font class="comment">*/</font> +00443 +00444 ZEXTERN <font class="keywordtype">int</font> ZEXPORT deflateSetDictionary OF((z_streamp strm, +00445 <font class="keyword">const</font> Bytef *dictionary, +00446 uInt dictLength)); +00447 <font class="comment">/* +</font>00448 <font class="comment"> Initializes the compression dictionary from the given byte sequence +</font>00449 <font class="comment"> without producing any compressed output. This function must be called +</font>00450 <font class="comment"> immediately after deflateInit, deflateInit2 or deflateReset, before any +</font>00451 <font class="comment"> call of deflate. The compressor and decompressor must use exactly the same +</font>00452 <font class="comment"> dictionary (see inflateSetDictionary). +</font>00453 <font class="comment"> +</font>00454 <font class="comment"> The dictionary should consist of strings (byte sequences) that are likely +</font>00455 <font class="comment"> to be encountered later in the data to be compressed, with the most commonly +</font>00456 <font class="comment"> used strings preferably put towards the end of the dictionary. Using a +</font>00457 <font class="comment"> dictionary is most useful when the data to be compressed is short and can be +</font>00458 <font class="comment"> predicted with good accuracy; the data can then be compressed better than +</font>00459 <font class="comment"> with the default empty dictionary. +</font>00460 <font class="comment"> +</font>00461 <font class="comment"> Depending on the size of the compression data structures selected by +</font>00462 <font class="comment"> deflateInit or deflateInit2, a part of the dictionary may in effect be +</font>00463 <font class="comment"> discarded, for example if the dictionary is larger than the window size in +</font>00464 <font class="comment"> deflate or deflate2. Thus the strings most likely to be useful should be +</font>00465 <font class="comment"> put at the end of the dictionary, not at the front. +</font>00466 <font class="comment"> +</font>00467 <font class="comment"> Upon return of this function, strm->adler is set to the Adler32 value +</font>00468 <font class="comment"> of the dictionary; the decompressor may later use this value to determine +</font>00469 <font class="comment"> which dictionary has been used by the compressor. (The Adler32 value +</font>00470 <font class="comment"> applies to the whole dictionary even if only a subset of the dictionary is +</font>00471 <font class="comment"> actually used by the compressor.) +</font>00472 <font class="comment"> +</font>00473 <font class="comment"> deflateSetDictionary returns Z_OK if success, or Z_STREAM_ERROR if a +</font>00474 <font class="comment"> parameter is invalid (such as NULL dictionary) or the stream state is +</font>00475 <font class="comment"> inconsistent (for example if deflate has already been called for this stream +</font>00476 <font class="comment"> or if the compression method is bsort). deflateSetDictionary does not +</font>00477 <font class="comment"> perform any compression: this will be done by deflate(). +</font>00478 <font class="comment">*/</font> +00479 +00480 ZEXTERN <font class="keywordtype">int</font> ZEXPORT deflateCopy OF((z_streamp dest, +00481 z_streamp source)); +00482 <font class="comment">/* +</font>00483 <font class="comment"> Sets the destination stream as a complete copy of the source stream. +</font>00484 <font class="comment"> +</font>00485 <font class="comment"> This function can be useful when several compression strategies will be +</font>00486 <font class="comment"> tried, for example when there are several ways of pre-processing the input +</font>00487 <font class="comment"> data with a filter. The streams that will be discarded should then be freed +</font>00488 <font class="comment"> by calling deflateEnd. Note that deflateCopy duplicates the internal +</font>00489 <font class="comment"> compression state which can be quite large, so this strategy is slow and +</font>00490 <font class="comment"> can consume lots of memory. +</font>00491 <font class="comment"> +</font>00492 <font class="comment"> deflateCopy returns Z_OK if success, Z_MEM_ERROR if there was not +</font>00493 <font class="comment"> enough memory, Z_STREAM_ERROR if the source stream state was inconsistent +</font>00494 <font class="comment"> (such as zalloc being NULL). msg is left unchanged in both source and +</font>00495 <font class="comment"> destination. +</font>00496 <font class="comment">*/</font> +00497 +00498 ZEXTERN <font class="keywordtype">int</font> ZEXPORT deflateReset OF((z_streamp strm)); +00499 <font class="comment">/* +</font>00500 <font class="comment"> This function is equivalent to deflateEnd followed by deflateInit, +</font>00501 <font class="comment"> but does not free and reallocate all the internal compression state. +</font>00502 <font class="comment"> The stream will keep the same compression level and any other attributes +</font>00503 <font class="comment"> that may have been set by deflateInit2. +</font>00504 <font class="comment"> +</font>00505 <font class="comment"> deflateReset returns Z_OK if success, or Z_STREAM_ERROR if the source +</font>00506 <font class="comment"> stream state was inconsistent (such as zalloc or state being NULL). +</font>00507 <font class="comment">*/</font> +00508 +00509 ZEXTERN <font class="keywordtype">int</font> ZEXPORT deflateParams OF((z_streamp strm, +00510 <font class="keywordtype">int</font> level, +00511 <font class="keywordtype">int</font> strategy)); +00512 <font class="comment">/* +</font>00513 <font class="comment"> Dynamically update the compression level and compression strategy. The +</font>00514 <font class="comment"> interpretation of level and strategy is as in deflateInit2. This can be +</font>00515 <font class="comment"> used to switch between compression and straight copy of the input data, or +</font>00516 <font class="comment"> to switch to a different kind of input data requiring a different +</font>00517 <font class="comment"> strategy. If the compression level is changed, the input available so far +</font>00518 <font class="comment"> is compressed with the old level (and may be flushed); the new level will +</font>00519 <font class="comment"> take effect only at the next call of deflate(). +</font>00520 <font class="comment"> +</font>00521 <font class="comment"> Before the call of deflateParams, the stream state must be set as for +</font>00522 <font class="comment"> a call of deflate(), since the currently available input may have to +</font>00523 <font class="comment"> be compressed and flushed. In particular, strm->avail_out must be non-zero. +</font>00524 <font class="comment"> +</font>00525 <font class="comment"> deflateParams returns Z_OK if success, Z_STREAM_ERROR if the source +</font>00526 <font class="comment"> stream state was inconsistent or if a parameter was invalid, Z_BUF_ERROR +</font>00527 <font class="comment"> if strm->avail_out was zero. +</font>00528 <font class="comment">*/</font> +00529 +00530 <font class="comment">/* +</font>00531 <font class="comment">ZEXTERN int ZEXPORT inflateInit2 OF((z_streamp strm, +</font>00532 <font class="comment"> int windowBits)); +</font>00533 <font class="comment"> +</font>00534 <font class="comment"> This is another version of inflateInit with an extra parameter. The +</font>00535 <font class="comment"> fields next_in, avail_in, zalloc, zfree and opaque must be initialized +</font>00536 <font class="comment"> before by the caller. +</font>00537 <font class="comment"> +</font>00538 <font class="comment"> The windowBits parameter is the base two logarithm of the maximum window +</font>00539 <font class="comment"> size (the size of the history buffer). It should be in the range 8..15 for +</font>00540 <font class="comment"> this version of the library. The default value is 15 if inflateInit is used +</font>00541 <font class="comment"> instead. If a compressed stream with a larger window size is given as +</font>00542 <font class="comment"> input, inflate() will return with the error code Z_DATA_ERROR instead of +</font>00543 <font class="comment"> trying to allocate a larger window. +</font>00544 <font class="comment"> +</font>00545 <font class="comment"> inflateInit2 returns Z_OK if success, Z_MEM_ERROR if there was not enough +</font>00546 <font class="comment"> memory, Z_STREAM_ERROR if a parameter is invalid (such as a negative +</font>00547 <font class="comment"> memLevel). msg is set to null if there is no error message. inflateInit2 +</font>00548 <font class="comment"> does not perform any decompression apart from reading the zlib header if +</font>00549 <font class="comment"> present: this will be done by inflate(). (So next_in and avail_in may be +</font>00550 <font class="comment"> modified, but next_out and avail_out are unchanged.) +</font>00551 <font class="comment">*/</font> +00552 +00553 ZEXTERN <font class="keywordtype">int</font> ZEXPORT inflateSetDictionary OF((z_streamp strm, +00554 <font class="keyword">const</font> Bytef *dictionary, +00555 uInt dictLength)); +00556 <font class="comment">/* +</font>00557 <font class="comment"> Initializes the decompression dictionary from the given uncompressed byte +</font>00558 <font class="comment"> sequence. This function must be called immediately after a call of inflate +</font>00559 <font class="comment"> if this call returned Z_NEED_DICT. The dictionary chosen by the compressor +</font>00560 <font class="comment"> can be determined from the Adler32 value returned by this call of +</font>00561 <font class="comment"> inflate. The compressor and decompressor must use exactly the same +</font>00562 <font class="comment"> dictionary (see deflateSetDictionary). +</font>00563 <font class="comment"> +</font>00564 <font class="comment"> inflateSetDictionary returns Z_OK if success, Z_STREAM_ERROR if a +</font>00565 <font class="comment"> parameter is invalid (such as NULL dictionary) or the stream state is +</font>00566 <font class="comment"> inconsistent, Z_DATA_ERROR if the given dictionary doesn't match the +</font>00567 <font class="comment"> expected one (incorrect Adler32 value). inflateSetDictionary does not +</font>00568 <font class="comment"> perform any decompression: this will be done by subsequent calls of +</font>00569 <font class="comment"> inflate(). +</font>00570 <font class="comment">*/</font> +00571 +00572 ZEXTERN <font class="keywordtype">int</font> ZEXPORT inflateSync OF((z_streamp strm)); +00573 <font class="comment">/* +</font>00574 <font class="comment"> Skips invalid compressed data until a full flush point (see above the +</font>00575 <font class="comment"> description of deflate with Z_FULL_FLUSH) can be found, or until all +</font>00576 <font class="comment"> available input is skipped. No output is provided. +</font>00577 <font class="comment"> +</font>00578 <font class="comment"> inflateSync returns Z_OK if a full flush point has been found, Z_BUF_ERROR +</font>00579 <font class="comment"> if no more input was provided, Z_DATA_ERROR if no flush point has been found, +</font>00580 <font class="comment"> or Z_STREAM_ERROR if the stream structure was inconsistent. In the success +</font>00581 <font class="comment"> case, the application may save the current current value of total_in which +</font>00582 <font class="comment"> indicates where valid compressed data was found. In the error case, the +</font>00583 <font class="comment"> application may repeatedly call inflateSync, providing more input each time, +</font>00584 <font class="comment"> until success or end of the input data. +</font>00585 <font class="comment">*/</font> +00586 +00587 ZEXTERN <font class="keywordtype">int</font> ZEXPORT inflateReset OF((z_streamp strm)); +00588 <font class="comment">/* +</font>00589 <font class="comment"> This function is equivalent to inflateEnd followed by inflateInit, +</font>00590 <font class="comment"> but does not free and reallocate all the internal decompression state. +</font>00591 <font class="comment"> The stream will keep attributes that may have been set by inflateInit2. +</font>00592 <font class="comment"> +</font>00593 <font class="comment"> inflateReset returns Z_OK if success, or Z_STREAM_ERROR if the source +</font>00594 <font class="comment"> stream state was inconsistent (such as zalloc or state being NULL). +</font>00595 <font class="comment">*/</font> +00596 +00597 +00598 <font class="comment">/* utility functions */</font> +00599 +00600 <font class="comment">/* +</font>00601 <font class="comment"> The following utility functions are implemented on top of the +</font>00602 <font class="comment"> basic stream-oriented functions. To simplify the interface, some +</font>00603 <font class="comment"> default options are assumed (compression level and memory usage, +</font>00604 <font class="comment"> standard memory allocation functions). The source code of these +</font>00605 <font class="comment"> utility functions can easily be modified if you need special options. +</font>00606 <font class="comment">*/</font> +00607 +00608 ZEXTERN <font class="keywordtype">int</font> ZEXPORT compress OF((Bytef *dest, uLongf *destLen, +00609 <font class="keyword">const</font> Bytef *source, uLong sourceLen)); +00610 <font class="comment">/* +</font>00611 <font class="comment"> Compresses the source buffer into the destination buffer. sourceLen is +</font>00612 <font class="comment"> the byte length of the source buffer. Upon entry, destLen is the total +</font>00613 <font class="comment"> size of the destination buffer, which must be at least 0.1% larger than +</font>00614 <font class="comment"> sourceLen plus 12 bytes. Upon exit, destLen is the actual size of the +</font>00615 <font class="comment"> compressed buffer. +</font>00616 <font class="comment"> This function can be used to compress a whole file at once if the +</font>00617 <font class="comment"> input file is mmap'ed. +</font>00618 <font class="comment"> compress returns Z_OK if success, Z_MEM_ERROR if there was not +</font>00619 <font class="comment"> enough memory, Z_BUF_ERROR if there was not enough room in the output +</font>00620 <font class="comment"> buffer. +</font>00621 <font class="comment">*/</font> +00622 +00623 ZEXTERN <font class="keywordtype">int</font> ZEXPORT compress2 OF((Bytef *dest, uLongf *destLen, +00624 <font class="keyword">const</font> Bytef *source, uLong sourceLen, +00625 <font class="keywordtype">int</font> level)); +00626 <font class="comment">/* +</font>00627 <font class="comment"> Compresses the source buffer into the destination buffer. The level +</font>00628 <font class="comment"> parameter has the same meaning as in deflateInit. sourceLen is the byte +</font>00629 <font class="comment"> length of the source buffer. Upon entry, destLen is the total size of the +</font>00630 <font class="comment"> destination buffer, which must be at least 0.1% larger than sourceLen plus +</font>00631 <font class="comment"> 12 bytes. Upon exit, destLen is the actual size of the compressed buffer. +</font>00632 <font class="comment"> +</font>00633 <font class="comment"> compress2 returns Z_OK if success, Z_MEM_ERROR if there was not enough +</font>00634 <font class="comment"> memory, Z_BUF_ERROR if there was not enough room in the output buffer, +</font>00635 <font class="comment"> Z_STREAM_ERROR if the level parameter is invalid. +</font>00636 <font class="comment">*/</font> +00637 +00638 ZEXTERN <font class="keywordtype">int</font> ZEXPORT uncompress OF((Bytef *dest, uLongf *destLen, +00639 <font class="keyword">const</font> Bytef *source, uLong sourceLen)); +00640 <font class="comment">/* +</font>00641 <font class="comment"> Decompresses the source buffer into the destination buffer. sourceLen is +</font>00642 <font class="comment"> the byte length of the source buffer. Upon entry, destLen is the total +</font>00643 <font class="comment"> size of the destination buffer, which must be large enough to hold the +</font>00644 <font class="comment"> entire uncompressed data. (The size of the uncompressed data must have +</font>00645 <font class="comment"> been saved previously by the compressor and transmitted to the decompressor +</font>00646 <font class="comment"> by some mechanism outside the scope of this compression library.) +</font>00647 <font class="comment"> Upon exit, destLen is the actual size of the compressed buffer. +</font>00648 <font class="comment"> This function can be used to decompress a whole file at once if the +</font>00649 <font class="comment"> input file is mmap'ed. +</font>00650 <font class="comment"> +</font>00651 <font class="comment"> uncompress returns Z_OK if success, Z_MEM_ERROR if there was not +</font>00652 <font class="comment"> enough memory, Z_BUF_ERROR if there was not enough room in the output +</font>00653 <font class="comment"> buffer, or Z_DATA_ERROR if the input data was corrupted. +</font>00654 <font class="comment">*/</font> +00655 +00656 +00657 <font class="keyword">typedef</font> voidp gzFile; +00658 +00659 ZEXTERN gzFile ZEXPORT gzopen OF((<font class="keyword">const</font> <font class="keywordtype">char</font> *path, <font class="keyword">const</font> <font class="keywordtype">char</font> *mode)); +00660 <font class="comment">/* +</font>00661 <font class="comment"> Opens a gzip (.gz) file for reading or writing. The mode parameter +</font>00662 <font class="comment"> is as in fopen ("rb" or "wb") but can also include a compression level +</font>00663 <font class="comment"> ("wb9") or a strategy: 'f' for filtered data as in "wb6f", 'h' for +</font>00664 <font class="comment"> Huffman only compression as in "wb1h". (See the description +</font>00665 <font class="comment"> of deflateInit2 for more information about the strategy parameter.) +</font>00666 <font class="comment"> +</font>00667 <font class="comment"> gzopen can be used to read a file which is not in gzip format; in this +</font>00668 <font class="comment"> case gzread will directly read from the file without decompression. +</font>00669 <font class="comment"> +</font>00670 <font class="comment"> gzopen returns NULL if the file could not be opened or if there was +</font>00671 <font class="comment"> insufficient memory to allocate the (de)compression state; errno +</font>00672 <font class="comment"> can be checked to distinguish the two cases (if errno is zero, the +</font>00673 <font class="comment"> zlib error is Z_MEM_ERROR). */</font> +00674 +00675 ZEXTERN gzFile ZEXPORT gzdopen OF((<font class="keywordtype">int</font> fd, <font class="keyword">const</font> <font class="keywordtype">char</font> *mode)); +00676 <font class="comment">/* +</font>00677 <font class="comment"> gzdopen() associates a gzFile with the file descriptor fd. File +</font>00678 <font class="comment"> descriptors are obtained from calls like open, dup, creat, pipe or +</font>00679 <font class="comment"> fileno (in the file has been previously opened with fopen). +</font>00680 <font class="comment"> The mode parameter is as in gzopen. +</font>00681 <font class="comment"> The next call of gzclose on the returned gzFile will also close the +</font>00682 <font class="comment"> file descriptor fd, just like fclose(fdopen(fd), mode) closes the file +</font>00683 <font class="comment"> descriptor fd. If you want to keep fd open, use gzdopen(dup(fd), mode). +</font>00684 <font class="comment"> gzdopen returns NULL if there was insufficient memory to allocate +</font>00685 <font class="comment"> the (de)compression state. +</font>00686 <font class="comment">*/</font> +00687 +00688 ZEXTERN <font class="keywordtype">int</font> ZEXPORT gzsetparams OF((gzFile file, <font class="keywordtype">int</font> level, <font class="keywordtype">int</font> strategy)); +00689 <font class="comment">/* +</font>00690 <font class="comment"> Dynamically update the compression level or strategy. See the description +</font>00691 <font class="comment"> of deflateInit2 for the meaning of these parameters. +</font>00692 <font class="comment"> gzsetparams returns Z_OK if success, or Z_STREAM_ERROR if the file was not +</font>00693 <font class="comment"> opened for writing. +</font>00694 <font class="comment">*/</font> +00695 +00696 ZEXTERN <font class="keywordtype">int</font> ZEXPORT gzread OF((gzFile file, voidp buf, <font class="keywordtype">unsigned</font> len)); +00697 <font class="comment">/* +</font>00698 <font class="comment"> Reads the given number of uncompressed bytes from the compressed file. +</font>00699 <font class="comment"> If the input file was not in gzip format, gzread copies the given number +</font>00700 <font class="comment"> of bytes into the buffer. +</font>00701 <font class="comment"> gzread returns the number of uncompressed bytes actually read (0 for +</font>00702 <font class="comment"> end of file, -1 for error). */</font> +00703 +00704 ZEXTERN <font class="keywordtype">int</font> ZEXPORT gzwrite OF((gzFile file, +00705 <font class="keyword">const</font> voidp buf, <font class="keywordtype">unsigned</font> len)); +00706 <font class="comment">/* +</font>00707 <font class="comment"> Writes the given number of uncompressed bytes into the compressed file. +</font>00708 <font class="comment"> gzwrite returns the number of uncompressed bytes actually written +</font>00709 <font class="comment"> (0 in case of error). +</font>00710 <font class="comment">*/</font> +00711 +00712 ZEXTERN <font class="keywordtype">int</font> ZEXPORTVA gzprintf OF((gzFile file, <font class="keyword">const</font> <font class="keywordtype">char</font> *format, ...)); +00713 <font class="comment">/* +</font>00714 <font class="comment"> Converts, formats, and writes the args to the compressed file under +</font>00715 <font class="comment"> control of the format string, as in fprintf. gzprintf returns the number of +</font>00716 <font class="comment"> uncompressed bytes actually written (0 in case of error). +</font>00717 <font class="comment">*/</font> +00718 +00719 ZEXTERN <font class="keywordtype">int</font> ZEXPORT gzputs OF((gzFile file, <font class="keyword">const</font> <font class="keywordtype">char</font> *s)); +00720 <font class="comment">/* +</font>00721 <font class="comment"> Writes the given null-terminated string to the compressed file, excluding +</font>00722 <font class="comment"> the terminating null character. +</font>00723 <font class="comment"> gzputs returns the number of characters written, or -1 in case of error. +</font>00724 <font class="comment">*/</font> +00725 +00726 ZEXTERN <font class="keywordtype">char</font> * ZEXPORT gzgets OF((gzFile file, <font class="keywordtype">char</font> *buf, <font class="keywordtype">int</font> len)); +00727 <font class="comment">/* +</font>00728 <font class="comment"> Reads bytes from the compressed file until len-1 characters are read, or +</font>00729 <font class="comment"> a newline character is read and transferred to buf, or an end-of-file +</font>00730 <font class="comment"> condition is encountered. The string is then terminated with a null +</font>00731 <font class="comment"> character. +</font>00732 <font class="comment"> gzgets returns buf, or Z_NULL in case of error. +</font>00733 <font class="comment">*/</font> +00734 +00735 ZEXTERN <font class="keywordtype">int</font> ZEXPORT gzputc OF((gzFile file, <font class="keywordtype">int</font> c)); +00736 <font class="comment">/* +</font>00737 <font class="comment"> Writes c, converted to an unsigned char, into the compressed file. +</font>00738 <font class="comment"> gzputc returns the value that was written, or -1 in case of error. +</font>00739 <font class="comment">*/</font> +00740 +00741 ZEXTERN <font class="keywordtype">int</font> ZEXPORT gzgetc OF((gzFile file)); +00742 <font class="comment">/* +</font>00743 <font class="comment"> Reads one byte from the compressed file. gzgetc returns this byte +</font>00744 <font class="comment"> or -1 in case of end of file or error. +</font>00745 <font class="comment">*/</font> +00746 +00747 ZEXTERN <font class="keywordtype">int</font> ZEXPORT gzflush OF((gzFile file, <font class="keywordtype">int</font> flush)); +00748 <font class="comment">/* +</font>00749 <font class="comment"> Flushes all pending output into the compressed file. The parameter +</font>00750 <font class="comment"> flush is as in the deflate() function. The return value is the zlib +</font>00751 <font class="comment"> error number (see function gzerror below). gzflush returns Z_OK if +</font>00752 <font class="comment"> the flush parameter is Z_FINISH and all output could be flushed. +</font>00753 <font class="comment"> gzflush should be called only when strictly necessary because it can +</font>00754 <font class="comment"> degrade compression. +</font>00755 <font class="comment">*/</font> +00756 +00757 ZEXTERN z_off_t ZEXPORT gzseek OF((gzFile file, +00758 z_off_t offset, <font class="keywordtype">int</font> whence)); +00759 <font class="comment">/* +</font>00760 <font class="comment"> Sets the starting position for the next gzread or gzwrite on the +</font>00761 <font class="comment"> given compressed file. The offset represents a number of bytes in the +</font>00762 <font class="comment"> uncompressed data stream. The whence parameter is defined as in lseek(2); +</font>00763 <font class="comment"> the value SEEK_END is not supported. +</font>00764 <font class="comment"> If the file is opened for reading, this function is emulated but can be +</font>00765 <font class="comment"> extremely slow. If the file is opened for writing, only forward seeks are +</font>00766 <font class="comment"> supported; gzseek then compresses a sequence of zeroes up to the new +</font>00767 <font class="comment"> starting position. +</font>00768 <font class="comment"> +</font>00769 <font class="comment"> gzseek returns the resulting offset location as measured in bytes from +</font>00770 <font class="comment"> the beginning of the uncompressed stream, or -1 in case of error, in +</font>00771 <font class="comment"> particular if the file is opened for writing and the new starting position +</font>00772 <font class="comment"> would be before the current position. +</font>00773 <font class="comment">*/</font> +00774 +00775 ZEXTERN <font class="keywordtype">int</font> ZEXPORT gzrewind OF((gzFile file)); +00776 <font class="comment">/* +</font>00777 <font class="comment"> Rewinds the given file. This function is supported only for reading. +</font>00778 <font class="comment"> +</font>00779 <font class="comment"> gzrewind(file) is equivalent to (int)gzseek(file, 0L, SEEK_SET) +</font>00780 <font class="comment">*/</font> +00781 +00782 ZEXTERN z_off_t ZEXPORT gztell OF((gzFile file)); +00783 <font class="comment">/* +</font>00784 <font class="comment"> Returns the starting position for the next gzread or gzwrite on the +</font>00785 <font class="comment"> given compressed file. This position represents a number of bytes in the +</font>00786 <font class="comment"> uncompressed data stream. +</font>00787 <font class="comment"> +</font>00788 <font class="comment"> gztell(file) is equivalent to gzseek(file, 0L, SEEK_CUR) +</font>00789 <font class="comment">*/</font> +00790 +00791 ZEXTERN <font class="keywordtype">int</font> ZEXPORT gzeof OF((gzFile file)); +00792 <font class="comment">/* +</font>00793 <font class="comment"> Returns 1 when EOF has previously been detected reading the given +</font>00794 <font class="comment"> input stream, otherwise zero. +</font>00795 <font class="comment">*/</font> +00796 +00797 ZEXTERN <font class="keywordtype">int</font> ZEXPORT gzclose OF((gzFile file)); +00798 <font class="comment">/* +</font>00799 <font class="comment"> Flushes all pending output if necessary, closes the compressed file +</font>00800 <font class="comment"> and deallocates all the (de)compression state. The return value is the zlib +</font>00801 <font class="comment"> error number (see function gzerror below). +</font>00802 <font class="comment">*/</font> +00803 +00804 ZEXTERN <font class="keyword">const</font> <font class="keywordtype">char</font> * ZEXPORT gzerror OF((gzFile file, <font class="keywordtype">int</font> *errnum)); +00805 <font class="comment">/* +</font>00806 <font class="comment"> Returns the error message for the last error which occurred on the +</font>00807 <font class="comment"> given compressed file. errnum is set to zlib error number. If an +</font>00808 <font class="comment"> error occurred in the file system and not in the compression library, +</font>00809 <font class="comment"> errnum is set to Z_ERRNO and the application may consult errno +</font>00810 <font class="comment"> to get the exact error code. +</font>00811 <font class="comment">*/</font> +00812 +00813 <font class="comment">/* checksum functions */</font> +00814 +00815 <font class="comment">/* +</font>00816 <font class="comment"> These functions are not related to compression but are exported +</font>00817 <font class="comment"> anyway because they might be useful in applications using the +</font>00818 <font class="comment"> compression library. +</font>00819 <font class="comment">*/</font> +00820 +00821 ZEXTERN uLong ZEXPORT adler32 OF((uLong adler, <font class="keyword">const</font> Bytef *buf, uInt len)); +00822 +00823 <font class="comment">/* +</font>00824 <font class="comment"> Update a running Adler-32 checksum with the bytes buf[0..len-1] and +</font>00825 <font class="comment"> return the updated checksum. If buf is NULL, this function returns +</font>00826 <font class="comment"> the required initial value for the checksum. +</font>00827 <font class="comment"> An Adler-32 checksum is almost as reliable as a CRC32 but can be computed +</font>00828 <font class="comment"> much faster. Usage example: +</font>00829 <font class="comment"> +</font>00830 <font class="comment"> uLong adler = adler32(0L, Z_NULL, 0); +</font>00831 <font class="comment"> +</font>00832 <font class="comment"> while (read_buffer(buffer, length) != EOF) { +</font>00833 <font class="comment"> adler = adler32(adler, buffer, length); +</font>00834 <font class="comment"> } +</font>00835 <font class="comment"> if (adler != original_adler) error(); +</font>00836 <font class="comment">*/</font> +00837 +00838 ZEXTERN uLong ZEXPORT crc32 OF((uLong crc, <font class="keyword">const</font> Bytef *buf, uInt len)); +00839 <font class="comment">/* +</font>00840 <font class="comment"> Update a running crc with the bytes buf[0..len-1] and return the updated +</font>00841 <font class="comment"> crc. If buf is NULL, this function returns the required initial value +</font>00842 <font class="comment"> for the crc. Pre- and post-conditioning (one's complement) is performed +</font>00843 <font class="comment"> within this function so it shouldn't be done by the application. +</font>00844 <font class="comment"> Usage example: +</font>00845 <font class="comment"> +</font>00846 <font class="comment"> uLong crc = crc32(0L, Z_NULL, 0); +</font>00847 <font class="comment"> +</font>00848 <font class="comment"> while (read_buffer(buffer, length) != EOF) { +</font>00849 <font class="comment"> crc = crc32(crc, buffer, length); +</font>00850 <font class="comment"> } +</font>00851 <font class="comment"> if (crc != original_crc) error(); +</font>00852 <font class="comment">*/</font> +00853 +00854 +00855 <font class="comment">/* various hacks, don't look :) */</font> +00856 +00857 <font class="comment">/* deflateInit and inflateInit are macros to allow checking the zlib version +</font>00858 <font class="comment"> * and the compiler's view of z_stream: +</font>00859 <font class="comment"> */</font> +00860 ZEXTERN <font class="keywordtype">int</font> ZEXPORT deflateInit_ OF((z_streamp strm, <font class="keywordtype">int</font> level, +00861 <font class="keyword">const</font> <font class="keywordtype">char</font> *version, <font class="keywordtype">int</font> stream_size)); +00862 ZEXTERN <font class="keywordtype">int</font> ZEXPORT inflateInit_ OF((z_streamp strm, +00863 <font class="keyword">const</font> <font class="keywordtype">char</font> *version, <font class="keywordtype">int</font> stream_size)); +00864 ZEXTERN <font class="keywordtype">int</font> ZEXPORT deflateInit2_ OF((z_streamp strm, <font class="keywordtype">int</font> level, <font class="keywordtype">int</font> method, +00865 <font class="keywordtype">int</font> windowBits, <font class="keywordtype">int</font> memLevel, +00866 <font class="keywordtype">int</font> strategy, <font class="keyword">const</font> <font class="keywordtype">char</font> *version, +00867 <font class="keywordtype">int</font> stream_size)); +00868 ZEXTERN <font class="keywordtype">int</font> ZEXPORT inflateInit2_ OF((z_streamp strm, <font class="keywordtype">int</font> windowBits, +00869 <font class="keyword">const</font> <font class="keywordtype">char</font> *version, <font class="keywordtype">int</font> stream_size)); +00870 <font class="preprocessor">#define deflateInit(strm, level) \ +</font>00871 <font class="preprocessor"> deflateInit_((strm), (level), ZLIB_VERSION, sizeof(z_stream)) +</font>00872 <font class="preprocessor"></font><font class="preprocessor">#define inflateInit(strm) \ +</font>00873 <font class="preprocessor"> inflateInit_((strm), ZLIB_VERSION, sizeof(z_stream)) +</font>00874 <font class="preprocessor"></font><font class="preprocessor">#define deflateInit2(strm, level, method, windowBits, memLevel, strategy) \ +</font>00875 <font class="preprocessor"> deflateInit2_((strm),(level),(method),(windowBits),(memLevel),\ +</font>00876 <font class="preprocessor"> (strategy), ZLIB_VERSION, sizeof(z_stream)) +</font>00877 <font class="preprocessor"></font><font class="preprocessor">#define inflateInit2(strm, windowBits) \ +</font>00878 <font class="preprocessor"> inflateInit2_((strm), (windowBits), ZLIB_VERSION, sizeof(z_stream)) +</font>00879 <font class="preprocessor"></font> +00880 +00881 <font class="preprocessor">#if !defined(_Z_UTIL_H) && !defined(NO_DUMMY_DECL) +</font>00882 <font class="preprocessor"></font> <font class="keyword">struct </font>internal_state {<font class="keywordtype">int</font> dummy;}; <font class="comment">/* hack for buggy compilers */</font> +00883 <font class="preprocessor">#endif +</font>00884 <font class="preprocessor"></font> +00885 ZEXTERN <font class="keyword">const</font> <font class="keywordtype">char</font> * ZEXPORT zError OF((<font class="keywordtype">int</font> err)); +00886 ZEXTERN <font class="keywordtype">int</font> ZEXPORT inflateSyncPoint OF((z_streamp z)); +00887 ZEXTERN <font class="keyword">const</font> uLongf * ZEXPORT get_crc_table OF((<font class="keywordtype">void</font>)); +00888 +00889 <font class="preprocessor">#ifdef __cplusplus +</font>00890 <font class="preprocessor"></font>} +00891 <font class="preprocessor">#endif +</font>00892 <font class="preprocessor"></font> +00893 <font class="preprocessor">#endif </font><font class="comment">/* _ZLIB_H */</font> +</div></pre><hr><address><small>Generated at Thu May 24 19:50:27 2001 for The Sword Project by +<a href="http://www.stack.nl/~dimitri/doxygen/index.html"> +<img src="doxygen.gif" alt="doxygen" align=center border=0 +width=110 height=53></a>1.1.5 written by <a href="mailto:dimitri@stack.nl">Dimitri van Heesch</a>, + © 1997-2000</small></address> +</body> +</html> |