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599 lines
28 KiB
599 lines
28 KiB
/* zlib.h -- interface of the 'zlib' general purpose compression library |
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Copyright (C) 1995-2005 Jean-loup Gailly and Mark Adler |
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This software is provided 'as-is', without any express or implied |
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warranty. In no event will the authors be held liable for any damages |
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arising from the use of this software. |
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Permission is granted to anyone to use this software for any purpose, |
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including commercial applications, and to alter it and redistribute it |
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freely, subject to the following restrictions: |
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1. The origin of this software must not be misrepresented; you must not |
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claim that you wrote the original software. If you use this software |
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in a product, an acknowledgment in the product documentation would be |
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appreciated but is not required. |
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2. Altered source versions must be plainly marked as such, and must not be |
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misrepresented as being the original software. |
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3. This notice may not be removed or altered from any source distribution. |
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Jean-loup Gailly Mark Adler |
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[email protected] [email protected] |
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The data format used by the zlib library is described by RFCs (Request for |
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Comments) 1950 to 1952 in the files https://www.ietf.org/rfc/rfc1950.txt |
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(zlib format), rfc1951.txt (deflate format) and rfc1952.txt (gzip format). |
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*/ |
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#ifndef _ZLIB_H |
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#define _ZLIB_H |
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#include <linux/zconf.h> |
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/* zlib deflate based on ZLIB_VERSION "1.1.3" */ |
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/* zlib inflate based on ZLIB_VERSION "1.2.3" */ |
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/* |
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This is a modified version of zlib for use inside the Linux kernel. |
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The main changes are to perform all memory allocation in advance. |
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Inflation Changes: |
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* Z_PACKET_FLUSH is added and used by ppp_deflate. Before returning |
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this checks there is no more input data available and the next data |
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is a STORED block. It also resets the mode to be read for the next |
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data, all as per PPP requirements. |
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* Addition of zlib_inflateIncomp which copies incompressible data into |
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the history window and adjusts the accoutning without calling |
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zlib_inflate itself to inflate the data. |
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*/ |
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/* |
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The 'zlib' compression library provides in-memory compression and |
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decompression functions, including integrity checks of the uncompressed |
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data. This version of the library supports only one compression method |
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(deflation) but other algorithms will be added later and will have the same |
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stream interface. |
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Compression can be done in a single step if the buffers are large |
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enough (for example if an input file is mmap'ed), or can be done by |
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repeated calls of the compression function. In the latter case, the |
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application must provide more input and/or consume the output |
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(providing more output space) before each call. |
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The compressed data format used by default by the in-memory functions is |
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the zlib format, which is a zlib wrapper documented in RFC 1950, wrapped |
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around a deflate stream, which is itself documented in RFC 1951. |
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The library also supports reading and writing files in gzip (.gz) format |
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with an interface similar to that of stdio. |
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The zlib format was designed to be compact and fast for use in memory |
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and on communications channels. The gzip format was designed for single- |
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file compression on file systems, has a larger header than zlib to maintain |
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directory information, and uses a different, slower check method than zlib. |
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The library does not install any signal handler. The decoder checks |
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the consistency of the compressed data, so the library should never |
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crash even in case of corrupted input. |
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*/ |
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struct internal_state; |
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typedef struct z_stream_s { |
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const Byte *next_in; /* next input byte */ |
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uLong avail_in; /* number of bytes available at next_in */ |
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uLong total_in; /* total nb of input bytes read so far */ |
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Byte *next_out; /* next output byte should be put there */ |
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uLong avail_out; /* remaining free space at next_out */ |
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uLong total_out; /* total nb of bytes output so far */ |
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char *msg; /* last error message, NULL if no error */ |
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struct internal_state *state; /* not visible by applications */ |
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void *workspace; /* memory allocated for this stream */ |
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int data_type; /* best guess about the data type: ascii or binary */ |
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uLong adler; /* adler32 value of the uncompressed data */ |
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uLong reserved; /* reserved for future use */ |
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} z_stream; |
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typedef z_stream *z_streamp; |
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/* |
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The application must update next_in and avail_in when avail_in has |
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dropped to zero. It must update next_out and avail_out when avail_out |
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has dropped to zero. The application must initialize zalloc, zfree and |
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opaque before calling the init function. All other fields are set by the |
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compression library and must not be updated by the application. |
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The opaque value provided by the application will be passed as the first |
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parameter for calls of zalloc and zfree. This can be useful for custom |
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memory management. The compression library attaches no meaning to the |
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opaque value. |
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zalloc must return NULL if there is not enough memory for the object. |
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If zlib is used in a multi-threaded application, zalloc and zfree must be |
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thread safe. |
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On 16-bit systems, the functions zalloc and zfree must be able to allocate |
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exactly 65536 bytes, but will not be required to allocate more than this |
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if the symbol MAXSEG_64K is defined (see zconf.h). WARNING: On MSDOS, |
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pointers returned by zalloc for objects of exactly 65536 bytes *must* |
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have their offset normalized to zero. The default allocation function |
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provided by this library ensures this (see zutil.c). To reduce memory |
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requirements and avoid any allocation of 64K objects, at the expense of |
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compression ratio, compile the library with -DMAX_WBITS=14 (see zconf.h). |
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The fields total_in and total_out can be used for statistics or |
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progress reports. After compression, total_in holds the total size of |
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the uncompressed data and may be saved for use in the decompressor |
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(particularly if the decompressor wants to decompress everything in |
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a single step). |
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*/ |
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/* constants */ |
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#define Z_NO_FLUSH 0 |
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#define Z_PARTIAL_FLUSH 1 /* will be removed, use Z_SYNC_FLUSH instead */ |
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#define Z_PACKET_FLUSH 2 |
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#define Z_SYNC_FLUSH 3 |
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#define Z_FULL_FLUSH 4 |
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#define Z_FINISH 5 |
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#define Z_BLOCK 6 /* Only for inflate at present */ |
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/* Allowed flush values; see deflate() and inflate() below for details */ |
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#define Z_OK 0 |
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#define Z_STREAM_END 1 |
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#define Z_NEED_DICT 2 |
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#define Z_ERRNO (-1) |
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#define Z_STREAM_ERROR (-2) |
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#define Z_DATA_ERROR (-3) |
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#define Z_MEM_ERROR (-4) |
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#define Z_BUF_ERROR (-5) |
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#define Z_VERSION_ERROR (-6) |
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/* Return codes for the compression/decompression functions. Negative |
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* values are errors, positive values are used for special but normal events. |
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*/ |
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#define Z_NO_COMPRESSION 0 |
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#define Z_BEST_SPEED 1 |
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#define Z_BEST_COMPRESSION 9 |
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#define Z_DEFAULT_COMPRESSION (-1) |
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/* compression levels */ |
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#define Z_FILTERED 1 |
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#define Z_HUFFMAN_ONLY 2 |
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#define Z_DEFAULT_STRATEGY 0 |
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/* compression strategy; see deflateInit2() below for details */ |
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#define Z_BINARY 0 |
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#define Z_ASCII 1 |
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#define Z_UNKNOWN 2 |
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/* Possible values of the data_type field */ |
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#define Z_DEFLATED 8 |
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/* The deflate compression method (the only one supported in this version) */ |
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/* basic functions */ |
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extern int zlib_deflate_workspacesize (int windowBits, int memLevel); |
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/* |
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Returns the number of bytes that needs to be allocated for a per- |
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stream workspace with the specified parameters. A pointer to this |
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number of bytes should be returned in stream->workspace before |
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you call zlib_deflateInit() or zlib_deflateInit2(). If you call |
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zlib_deflateInit(), specify windowBits = MAX_WBITS and memLevel = |
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MAX_MEM_LEVEL here. If you call zlib_deflateInit2(), the windowBits |
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and memLevel parameters passed to zlib_deflateInit2() must not |
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exceed those passed here. |
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*/ |
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extern int zlib_deflate_dfltcc_enabled (void); |
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/* |
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Returns 1 if Deflate-Conversion facility is installed and enabled, |
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otherwise 0. |
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*/ |
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/* |
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extern int deflateInit (z_streamp strm, int level); |
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Initializes the internal stream state for compression. The fields |
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zalloc, zfree and opaque must be initialized before by the caller. |
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If zalloc and zfree are set to NULL, deflateInit updates them to |
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use default allocation functions. |
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The compression level must be Z_DEFAULT_COMPRESSION, or between 0 and 9: |
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1 gives best speed, 9 gives best compression, 0 gives no compression at |
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all (the input data is simply copied a block at a time). |
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Z_DEFAULT_COMPRESSION requests a default compromise between speed and |
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compression (currently equivalent to level 6). |
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deflateInit returns Z_OK if success, Z_MEM_ERROR if there was not |
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enough memory, Z_STREAM_ERROR if level is not a valid compression level, |
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Z_VERSION_ERROR if the zlib library version (zlib_version) is incompatible |
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with the version assumed by the caller (ZLIB_VERSION). |
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msg is set to null if there is no error message. deflateInit does not |
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perform any compression: this will be done by deflate(). |
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*/ |
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extern int zlib_deflate (z_streamp strm, int flush); |
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/* |
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deflate compresses as much data as possible, and stops when the input |
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buffer becomes empty or the output buffer becomes full. It may introduce some |
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output latency (reading input without producing any output) except when |
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forced to flush. |
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The detailed semantics are as follows. deflate performs one or both of the |
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following actions: |
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- Compress more input starting at next_in and update next_in and avail_in |
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accordingly. If not all input can be processed (because there is not |
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enough room in the output buffer), next_in and avail_in are updated and |
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processing will resume at this point for the next call of deflate(). |
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- Provide more output starting at next_out and update next_out and avail_out |
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accordingly. This action is forced if the parameter flush is non zero. |
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Forcing flush frequently degrades the compression ratio, so this parameter |
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should be set only when necessary (in interactive applications). |
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Some output may be provided even if flush is not set. |
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Before the call of deflate(), the application should ensure that at least |
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one of the actions is possible, by providing more input and/or consuming |
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more output, and updating avail_in or avail_out accordingly; avail_out |
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should never be zero before the call. The application can consume the |
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compressed output when it wants, for example when the output buffer is full |
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(avail_out == 0), or after each call of deflate(). If deflate returns Z_OK |
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and with zero avail_out, it must be called again after making room in the |
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output buffer because there might be more output pending. |
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If the parameter flush is set to Z_SYNC_FLUSH, all pending output is |
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flushed to the output buffer and the output is aligned on a byte boundary, so |
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that the decompressor can get all input data available so far. (In particular |
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avail_in is zero after the call if enough output space has been provided |
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before the call.) Flushing may degrade compression for some compression |
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algorithms and so it should be used only when necessary. |
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If flush is set to Z_FULL_FLUSH, all output is flushed as with |
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Z_SYNC_FLUSH, and the compression state is reset so that decompression can |
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restart from this point if previous compressed data has been damaged or if |
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random access is desired. Using Z_FULL_FLUSH too often can seriously degrade |
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the compression. |
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If deflate returns with avail_out == 0, this function must be called again |
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with the same value of the flush parameter and more output space (updated |
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avail_out), until the flush is complete (deflate returns with non-zero |
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avail_out). |
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If the parameter flush is set to Z_FINISH, pending input is processed, |
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pending output is flushed and deflate returns with Z_STREAM_END if there |
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was enough output space; if deflate returns with Z_OK, this function must be |
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called again with Z_FINISH and more output space (updated avail_out) but no |
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more input data, until it returns with Z_STREAM_END or an error. After |
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deflate has returned Z_STREAM_END, the only possible operations on the |
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stream are deflateReset or deflateEnd. |
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Z_FINISH can be used immediately after deflateInit if all the compression |
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is to be done in a single step. In this case, avail_out must be at least |
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0.1% larger than avail_in plus 12 bytes. If deflate does not return |
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Z_STREAM_END, then it must be called again as described above. |
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deflate() sets strm->adler to the adler32 checksum of all input read |
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so far (that is, total_in bytes). |
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deflate() may update data_type if it can make a good guess about |
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the input data type (Z_ASCII or Z_BINARY). In doubt, the data is considered |
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binary. This field is only for information purposes and does not affect |
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the compression algorithm in any manner. |
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deflate() returns Z_OK if some progress has been made (more input |
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processed or more output produced), Z_STREAM_END if all input has been |
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consumed and all output has been produced (only when flush is set to |
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Z_FINISH), Z_STREAM_ERROR if the stream state was inconsistent (for example |
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if next_in or next_out was NULL), Z_BUF_ERROR if no progress is possible |
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(for example avail_in or avail_out was zero). |
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*/ |
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extern int zlib_deflateEnd (z_streamp strm); |
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/* |
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All dynamically allocated data structures for this stream are freed. |
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This function discards any unprocessed input and does not flush any |
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pending output. |
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deflateEnd returns Z_OK if success, Z_STREAM_ERROR if the |
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stream state was inconsistent, Z_DATA_ERROR if the stream was freed |
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prematurely (some input or output was discarded). In the error case, |
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msg may be set but then points to a static string (which must not be |
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deallocated). |
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*/ |
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extern int zlib_inflate_workspacesize (void); |
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/* |
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Returns the number of bytes that needs to be allocated for a per- |
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stream workspace. A pointer to this number of bytes should be |
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returned in stream->workspace before calling zlib_inflateInit(). |
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*/ |
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/* |
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extern int zlib_inflateInit (z_streamp strm); |
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Initializes the internal stream state for decompression. The fields |
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next_in, avail_in, and workspace must be initialized before by |
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the caller. If next_in is not NULL and avail_in is large enough (the exact |
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value depends on the compression method), inflateInit determines the |
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compression method from the zlib header and allocates all data structures |
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accordingly; otherwise the allocation will be deferred to the first call of |
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inflate. If zalloc and zfree are set to NULL, inflateInit updates them to |
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use default allocation functions. |
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inflateInit returns Z_OK if success, Z_MEM_ERROR if there was not enough |
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memory, Z_VERSION_ERROR if the zlib library version is incompatible with the |
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version assumed by the caller. msg is set to null if there is no error |
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message. inflateInit does not perform any decompression apart from reading |
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the zlib header if present: this will be done by inflate(). (So next_in and |
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avail_in may be modified, but next_out and avail_out are unchanged.) |
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*/ |
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extern int zlib_inflate (z_streamp strm, int flush); |
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/* |
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inflate decompresses as much data as possible, and stops when the input |
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buffer becomes empty or the output buffer becomes full. It may introduce |
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some output latency (reading input without producing any output) except when |
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forced to flush. |
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The detailed semantics are as follows. inflate performs one or both of the |
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following actions: |
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- Decompress more input starting at next_in and update next_in and avail_in |
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accordingly. If not all input can be processed (because there is not |
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enough room in the output buffer), next_in is updated and processing |
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will resume at this point for the next call of inflate(). |
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- Provide more output starting at next_out and update next_out and avail_out |
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accordingly. inflate() provides as much output as possible, until there |
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is no more input data or no more space in the output buffer (see below |
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about the flush parameter). |
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Before the call of inflate(), the application should ensure that at least |
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one of the actions is possible, by providing more input and/or consuming |
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more output, and updating the next_* and avail_* values accordingly. |
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The application can consume the uncompressed output when it wants, for |
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example when the output buffer is full (avail_out == 0), or after each |
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call of inflate(). If inflate returns Z_OK and with zero avail_out, it |
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must be called again after making room in the output buffer because there |
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might be more output pending. |
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The flush parameter of inflate() can be Z_NO_FLUSH, Z_SYNC_FLUSH, |
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Z_FINISH, or Z_BLOCK. Z_SYNC_FLUSH requests that inflate() flush as much |
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output as possible to the output buffer. Z_BLOCK requests that inflate() stop |
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if and when it gets to the next deflate block boundary. When decoding the |
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zlib or gzip format, this will cause inflate() to return immediately after |
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the header and before the first block. When doing a raw inflate, inflate() |
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will go ahead and process the first block, and will return when it gets to |
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the end of that block, or when it runs out of data. |
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The Z_BLOCK option assists in appending to or combining deflate streams. |
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Also to assist in this, on return inflate() will set strm->data_type to the |
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number of unused bits in the last byte taken from strm->next_in, plus 64 |
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if inflate() is currently decoding the last block in the deflate stream, |
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plus 128 if inflate() returned immediately after decoding an end-of-block |
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code or decoding the complete header up to just before the first byte of the |
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deflate stream. The end-of-block will not be indicated until all of the |
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uncompressed data from that block has been written to strm->next_out. The |
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number of unused bits may in general be greater than seven, except when |
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bit 7 of data_type is set, in which case the number of unused bits will be |
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less than eight. |
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inflate() should normally be called until it returns Z_STREAM_END or an |
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error. However if all decompression is to be performed in a single step |
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(a single call of inflate), the parameter flush should be set to |
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Z_FINISH. In this case all pending input is processed and all pending |
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output is flushed; avail_out must be large enough to hold all the |
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uncompressed data. (The size of the uncompressed data may have been saved |
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by the compressor for this purpose.) The next operation on this stream must |
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be inflateEnd to deallocate the decompression state. The use of Z_FINISH |
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is never required, but can be used to inform inflate that a faster approach |
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may be used for the single inflate() call. |
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In this implementation, inflate() always flushes as much output as |
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possible to the output buffer, and always uses the faster approach on the |
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first call. So the only effect of the flush parameter in this implementation |
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is on the return value of inflate(), as noted below, or when it returns early |
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because Z_BLOCK is used. |
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If a preset dictionary is needed after this call (see inflateSetDictionary |
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below), inflate sets strm->adler to the adler32 checksum of the dictionary |
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chosen by the compressor and returns Z_NEED_DICT; otherwise it sets |
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strm->adler to the adler32 checksum of all output produced so far (that is, |
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total_out bytes) and returns Z_OK, Z_STREAM_END or an error code as described |
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below. At the end of the stream, inflate() checks that its computed adler32 |
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checksum is equal to that saved by the compressor and returns Z_STREAM_END |
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only if the checksum is correct. |
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inflate() will decompress and check either zlib-wrapped or gzip-wrapped |
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deflate data. The header type is detected automatically. Any information |
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contained in the gzip header is not retained, so applications that need that |
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information should instead use raw inflate, see inflateInit2() below, or |
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inflateBack() and perform their own processing of the gzip header and |
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trailer. |
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inflate() returns Z_OK if some progress has been made (more input processed |
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or more output produced), Z_STREAM_END if the end of the compressed data has |
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been reached and all uncompressed output has been produced, Z_NEED_DICT if a |
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preset dictionary is needed at this point, Z_DATA_ERROR if the input data was |
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corrupted (input stream not conforming to the zlib format or incorrect check |
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value), Z_STREAM_ERROR if the stream structure was inconsistent (for example |
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if next_in or next_out was NULL), Z_MEM_ERROR if there was not enough memory, |
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Z_BUF_ERROR if no progress is possible or if there was not enough room in the |
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output buffer when Z_FINISH is used. Note that Z_BUF_ERROR is not fatal, and |
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inflate() can be called again with more input and more output space to |
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continue decompressing. If Z_DATA_ERROR is returned, the application may then |
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call inflateSync() to look for a good compression block if a partial recovery |
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of the data is desired. |
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*/ |
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extern int zlib_inflateEnd (z_streamp strm); |
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/* |
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All dynamically allocated data structures for this stream are freed. |
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This function discards any unprocessed input and does not flush any |
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pending output. |
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inflateEnd returns Z_OK if success, Z_STREAM_ERROR if the stream state |
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was inconsistent. In the error case, msg may be set but then points to a |
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static string (which must not be deallocated). |
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*/ |
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/* Advanced functions */ |
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/* |
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The following functions are needed only in some special applications. |
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*/ |
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/* |
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extern int deflateInit2 (z_streamp strm, |
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int level, |
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int method, |
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int windowBits, |
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int memLevel, |
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int strategy); |
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This is another version of deflateInit with more compression options. The |
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fields next_in, zalloc, zfree and opaque must be initialized before by |
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the caller. |
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The method parameter is the compression method. It must be Z_DEFLATED in |
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this version of the library. |
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The windowBits parameter is the base two logarithm of the window size |
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(the size of the history buffer). It should be in the range 8..15 for this |
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version of the library. Larger values of this parameter result in better |
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compression at the expense of memory usage. The default value is 15 if |
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deflateInit is used instead. |
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The memLevel parameter specifies how much memory should be allocated |
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for the internal compression state. memLevel=1 uses minimum memory but |
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is slow and reduces compression ratio; memLevel=9 uses maximum memory |
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for optimal speed. The default value is 8. See zconf.h for total memory |
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usage as a function of windowBits and memLevel. |
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|
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The strategy parameter is used to tune the compression algorithm. Use the |
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value Z_DEFAULT_STRATEGY for normal data, Z_FILTERED for data produced by a |
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filter (or predictor), or Z_HUFFMAN_ONLY to force Huffman encoding only (no |
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string match). Filtered data consists mostly of small values with a |
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somewhat random distribution. In this case, the compression algorithm is |
|
tuned to compress them better. The effect of Z_FILTERED is to force more |
|
Huffman coding and less string matching; it is somewhat intermediate |
|
between Z_DEFAULT and Z_HUFFMAN_ONLY. The strategy parameter only affects |
|
the compression ratio but not the correctness of the compressed output even |
|
if it is not set appropriately. |
|
|
|
deflateInit2 returns Z_OK if success, Z_MEM_ERROR if there was not enough |
|
memory, Z_STREAM_ERROR if a parameter is invalid (such as an invalid |
|
method). msg is set to null if there is no error message. deflateInit2 does |
|
not perform any compression: this will be done by deflate(). |
|
*/ |
|
|
|
extern int zlib_deflateReset (z_streamp strm); |
|
/* |
|
This function is equivalent to deflateEnd followed by deflateInit, |
|
but does not free and reallocate all the internal compression state. |
|
The stream will keep the same compression level and any other attributes |
|
that may have been set by deflateInit2. |
|
|
|
deflateReset returns Z_OK if success, or Z_STREAM_ERROR if the source |
|
stream state was inconsistent (such as zalloc or state being NULL). |
|
*/ |
|
|
|
static inline unsigned long deflateBound(unsigned long s) |
|
{ |
|
return s + ((s + 7) >> 3) + ((s + 63) >> 6) + 11; |
|
} |
|
|
|
/* |
|
extern int inflateInit2 (z_streamp strm, int windowBits); |
|
|
|
This is another version of inflateInit with an extra parameter. The |
|
fields next_in, avail_in, zalloc, zfree and opaque must be initialized |
|
before by the caller. |
|
|
|
The windowBits parameter is the base two logarithm of the maximum window |
|
size (the size of the history buffer). It should be in the range 8..15 for |
|
this version of the library. The default value is 15 if inflateInit is used |
|
instead. windowBits must be greater than or equal to the windowBits value |
|
provided to deflateInit2() while compressing, or it must be equal to 15 if |
|
deflateInit2() was not used. If a compressed stream with a larger window |
|
size is given as input, inflate() will return with the error code |
|
Z_DATA_ERROR instead of trying to allocate a larger window. |
|
|
|
windowBits can also be -8..-15 for raw inflate. In this case, -windowBits |
|
determines the window size. inflate() will then process raw deflate data, |
|
not looking for a zlib or gzip header, not generating a check value, and not |
|
looking for any check values for comparison at the end of the stream. This |
|
is for use with other formats that use the deflate compressed data format |
|
such as zip. Those formats provide their own check values. If a custom |
|
format is developed using the raw deflate format for compressed data, it is |
|
recommended that a check value such as an adler32 or a crc32 be applied to |
|
the uncompressed data as is done in the zlib, gzip, and zip formats. For |
|
most applications, the zlib format should be used as is. Note that comments |
|
above on the use in deflateInit2() applies to the magnitude of windowBits. |
|
|
|
windowBits can also be greater than 15 for optional gzip decoding. Add |
|
32 to windowBits to enable zlib and gzip decoding with automatic header |
|
detection, or add 16 to decode only the gzip format (the zlib format will |
|
return a Z_DATA_ERROR). If a gzip stream is being decoded, strm->adler is |
|
a crc32 instead of an adler32. |
|
|
|
inflateInit2 returns Z_OK if success, Z_MEM_ERROR if there was not enough |
|
memory, Z_STREAM_ERROR if a parameter is invalid (such as a null strm). msg |
|
is set to null if there is no error message. inflateInit2 does not perform |
|
any decompression apart from reading the zlib header if present: this will |
|
be done by inflate(). (So next_in and avail_in may be modified, but next_out |
|
and avail_out are unchanged.) |
|
*/ |
|
|
|
extern int zlib_inflateReset (z_streamp strm); |
|
/* |
|
This function is equivalent to inflateEnd followed by inflateInit, |
|
but does not free and reallocate all the internal decompression state. |
|
The stream will keep attributes that may have been set by inflateInit2. |
|
|
|
inflateReset returns Z_OK if success, or Z_STREAM_ERROR if the source |
|
stream state was inconsistent (such as zalloc or state being NULL). |
|
*/ |
|
|
|
extern int zlib_inflateIncomp (z_stream *strm); |
|
/* |
|
This function adds the data at next_in (avail_in bytes) to the output |
|
history without performing any output. There must be no pending output, |
|
and the decompressor must be expecting to see the start of a block. |
|
Calling this function is equivalent to decompressing a stored block |
|
containing the data at next_in (except that the data is not output). |
|
*/ |
|
|
|
#define zlib_deflateInit(strm, level) \ |
|
zlib_deflateInit2((strm), (level), Z_DEFLATED, MAX_WBITS, \ |
|
DEF_MEM_LEVEL, Z_DEFAULT_STRATEGY) |
|
#define zlib_inflateInit(strm) \ |
|
zlib_inflateInit2((strm), DEF_WBITS) |
|
|
|
extern int zlib_deflateInit2(z_streamp strm, int level, int method, |
|
int windowBits, int memLevel, |
|
int strategy); |
|
extern int zlib_inflateInit2(z_streamp strm, int windowBits); |
|
|
|
#if !defined(_Z_UTIL_H) && !defined(NO_DUMMY_DECL) |
|
struct internal_state {int dummy;}; /* hack for buggy compilers */ |
|
#endif |
|
|
|
/* Utility function: initialize zlib, unpack binary blob, clean up zlib, |
|
* return len or negative error code. */ |
|
extern int zlib_inflate_blob(void *dst, unsigned dst_sz, const void *src, unsigned src_sz); |
|
|
|
#endif /* _ZLIB_H */
|
|
|