636 lines
28 KiB
C
Executable File
636 lines
28 KiB
C
Executable File
//
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// ZLIB.H
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//
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// Source file for ArchiveLib 2.0
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//
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// No Copyright claimed by Greenleaf Software!
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//
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// DESCRIPTION
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//
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// This is one of the ZLIB source files, with as few changes as possible.
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//
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// REVISION HISTORY
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//
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// February 14, 1996 2.0A : New release
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/* zlib.h -- interface of the 'zlib' general purpose compression library
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version 0.93 June 25th, 1995.
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Copyright (C) 1995 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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gzip@prep.ai.mit.edu madler@alumni.caltech.edu
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*/
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#ifndef _ZLIB_H
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#define _ZLIB_H
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#include "zconf.h"
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#define ZLIB_VERSION "0.93"
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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 may be added later and will have the same
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stream interface.
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For compression the application must provide the output buffer and
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may optionally provide the input buffer for optimization. For decompression,
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the application must provide the input buffer and may optionally provide
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the output buffer for optimization.
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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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*/
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typedef voidp (*alloc_func) __P((voidp opaque, uInt items, uInt size));
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typedef void (*free_func) __P((voidp opaque, voidp address));
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struct internal_state;
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typedef struct z_stream_s {
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Byte ZL_FAR *next_in; /* next input byte */
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uInt 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 ZL_FAR *next_out; /* next output byte should be put there */
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uInt 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 ZL_FAR *state; /* not visible by applications */
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alloc_func zalloc; /* used to allocate the internal state */
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free_func zfree; /* used to free the internal state */
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voidp opaque; /* private data object passed to zalloc and zfree */
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Byte data_type; /* best guess about the data type: ascii or binary */
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} z_stream;
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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 Z_NULL if there is not enough memory for the object.
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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
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#define Z_FULL_FLUSH 2
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#define Z_SYNC_FLUSH 3 /* experimental: partial_flush + byte align */
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#define Z_FINISH 4
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/* See deflate() below for the usage of these constants */
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#define Z_OK 0
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#define Z_STREAM_END 1
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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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/* error codes for the compression/decompression functions */
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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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#define Z_BINARY 0
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#define Z_ASCII 1
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#define Z_UNKNOWN 2
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/* Used to set the data_type field */
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#define Z_NULL 0 /* for initializing zalloc, zfree, opaque */
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extern char *zlib_version;
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/* The application can compare zlib_version and ZLIB_VERSION for consistency.
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If the first character differs, the library code actually used is
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not compatible with the zlib.h header file used by the application.
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*/
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/* basic functions */
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extern int deflateInit __P((z_stream *strm, int level));
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/*
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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 Z_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 1 and 9:
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1 gives best speed, 9 gives best compression. Z_DEFAULT_COMPRESSION requests
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a default compromise between speed and compression (currently equivalent
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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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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 deflate __P((z_stream *strm, int flush));
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/*
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Performs one or both of the 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().
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If the parameter flush is set to Z_PARTIAL_FLUSH, the current compression
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block is terminated and flushed to the output buffer so that the
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decompressor can get all input data available so far. For method 9, a future
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variant on method 8, the current block will be flushed but not terminated.
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If flush is set to Z_FULL_FLUSH, the compression block is terminated, a
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special marker is output and the compression dictionary is discarded; this
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is useful to allow the decompressor to synchronize if one compressed block
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has been damaged (see inflateSync below). Flushing degrades compression and
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so should be used only when necessary. Using Z_FULL_FLUSH too often can
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seriously degrade the compression.
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If the parameter flush is set to Z_FINISH, all pending input is processed,
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all 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() 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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*/
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extern int deflateEnd __P((z_stream *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. In the error case, msg may be set
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but then points to a static string (which must not be deallocated).
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*/
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extern int inflateInit __P((z_stream *strm));
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/*
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Initializes the internal stream state for decompression. The fields
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zalloc and zfree must be initialized before by the caller. If zalloc and
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zfree are set to Z_NULL, deflateInit updates them to use default allocation
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functions.
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inflateInit returns Z_OK if success, Z_MEM_ERROR if there was not
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enough memory. msg is set to null if there is no error message.
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inflateInit does not perform any decompression: this will be done by
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inflate().
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*/
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extern int inflate __P((z_stream *strm, int flush));
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/*
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Performs one or both of the 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() always provides as much output as possible
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(until no more input data or no more space in the output buffer).
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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().
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If the parameter flush is set to Z_PARTIAL_FLUSH, inflate flushes as much
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output as possible to the output buffer. The flushing behavior of inflate is
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not specified for values of the flush parameter other than Z_PARTIAL_FLUSH
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and Z_FINISH, but the current implementation actually flushes as much output
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as possible anyway.
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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.
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inflate() returns Z_OK if some progress has been made (more input
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processed or more output produced), Z_STREAM_END if the end of the
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compressed data has been reached and all uncompressed output has been
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produced, Z_DATA_ERROR if the input data was corrupted, Z_STREAM_ERROR if
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the stream structure was inconsistent (for example if next_in or next_out
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was NULL), Z_MEM_ERROR if there was not enough memory, Z_BUF_ERROR if no
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progress is possible or if there was not enough room in the output buffer
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when Z_FINISH is used. In the Z_DATA_ERROR case, the application may then
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call inflateSync to look for a good compression block.
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*/
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extern int inflateEnd __P((z_stream *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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extern int deflateInit2 __P((z_stream *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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/*
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This is another version of deflateInit with more compression options. The
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fields next_in, zalloc and zfree must be initialized before by the caller.
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The method parameter is the compression method. It must be 8 in this
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version of the library. (Method 9 will allow a 64K history buffer and
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partial block flushes.)
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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 (the value 16 will be allowed for method 9). Larger
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values of this parameter result in better compression at the expense of
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memory usage. The default value is 15 if 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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The strategy parameter is used to tune the compression algorithm. Use
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the value Z_DEFAULT_STRATEGY for normal data, Z_FILTERED for data
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produced by a filter (or predictor), or Z_HUFFMAN_ONLY to force Huffman
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encoding only (no string match). Filtered data consists mostly of small
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values with a somewhat random distribution. In this case, the
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compression algorithm is tuned to compress them better. The strategy
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parameter only affects the compression ratio but not the correctness of
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the compressed output even if it is not set appropriately.
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If next_in is not null, the library will use this buffer to hold also
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some history information; the buffer must either hold the entire input
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data, or have at least 1<<(windowBits+1) bytes and be writable. If next_in
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is null, the library will allocate its own history buffer (and leave next_in
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null). next_out need not be provided here but must be provided by the
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application for the next call of deflate().
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If the history buffer is provided by the application, next_in must
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must never be changed by the application since the compressor maintains
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information inside this buffer from call to call; the application
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must provide more input only by increasing avail_in. next_in is always
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reset by the library in this case.
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deflateInit2 returns Z_OK if success, Z_MEM_ERROR if there was
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not enough memory, Z_STREAM_ERROR if a parameter is invalid (such as
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an invalid method). msg is set to null if there is no error message.
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deflateInit2 does not perform any compression: this will be done by
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deflate().
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*/
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extern int deflateCopy __P((z_stream *dest,
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z_stream *source));
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/*
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Sets the destination stream as a complete copy of the source stream. If
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the source stream is using an application-supplied history buffer, a new
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buffer is allocated for the destination stream. The compressed output
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buffer is always application-supplied. It's the responsibility of the
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application to provide the correct values of next_out and avail_out for the
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next call of deflate.
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This function is useful when several compression strategies will be
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tried, for example when there are several ways of pre-processing the input
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data with a filter. The streams that will be discarded should then be freed
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by calling deflateEnd. Note that deflateCopy duplicates the internal
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compression state which can be quite large, so this strategy is slow and
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can consume lots of memory.
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deflateCopy returns Z_OK if success, Z_MEM_ERROR if there was not
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enough memory, Z_STREAM_ERROR if the source stream state was inconsistent
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(such as zalloc being NULL). msg is left unchanged in both source and
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destination.
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*/
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extern int deflateReset __P((z_stream *strm));
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/*
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This function is equivalent to deflateEnd followed by deflateInit,
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but does not free and reallocate all the internal compression state.
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The stream will keep the same compression level and any other attributes
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that may have been set by deflateInit2.
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deflateReset returns Z_OK if success, or Z_STREAM_ERROR if the source
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stream state was inconsistent (such as zalloc or state being NULL).
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*/
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extern int inflateInit2 __P((z_stream *strm,
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int windowBits));
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/*
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This is another version of inflateInit with more compression options. The
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fields next_out, zalloc and zfree must be initialized before by the caller.
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The windowBits parameter is the base two logarithm of the maximum window
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size (the size of the history buffer). It should be in the range 8..15 for
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this version of the library (the value 16 will be allowed soon). The
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default value is 15 if inflateInit is used instead. If a compressed stream
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with a larger window size is given as input, inflate() will return with
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the error code Z_DATA_ERROR instead of trying to allocate a larger window.
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If next_out is not null, the library will use this buffer for the history
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buffer; the buffer must either be large enough to hold the entire output
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data, or have at least 1<<windowBits bytes. If next_out is null, the
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library will allocate its own buffer (and leave next_out null). next_in
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need not be provided here but must be provided by the application for the
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next call of inflate().
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If the history buffer is provided by the application, next_out must
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never be changed by the application since the decompressor maintains
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history information inside this buffer from call to call; the application
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can only reset next_out to the beginning of the history buffer when
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avail_out is zero and all output has been consumed.
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inflateInit2 returns Z_OK if success, Z_MEM_ERROR if there was
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not enough memory, Z_STREAM_ERROR if a parameter is invalid (such as
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windowBits < 8). msg is set to null if there is no error message.
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inflateInit2 does not perform any compression: this will be done by
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inflate().
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*/
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extern int inflateSync __P((z_stream *strm));
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/*
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Skips invalid compressed data until the special marker (see deflate()
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above) can be found, or until all available input is skipped. No output
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is provided.
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inflateSync returns Z_OK if the special marker has been found, Z_BUF_ERROR
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if no more input was provided, Z_DATA_ERROR if no marker has been found,
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or Z_STREAM_ERROR if the stream structure was inconsistent. In the success
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case, the application may save the current current value of total_in which
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indicates where valid compressed data was found. In the error case, the
|
|
application may repeatedly call inflateSync, providing more input each time,
|
|
until success or end of the input data.
|
|
*/
|
|
|
|
extern int inflateReset __P((z_stream *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).
|
|
*/
|
|
|
|
|
|
/* utility functions */
|
|
|
|
/*
|
|
The following utility functions are implemented on top of the
|
|
basic stream-oriented functions. To simplify the interface, some
|
|
default options are assumed (compression level, window size,
|
|
standard memory allocation functions). The source code of these
|
|
utility functions can easily be modified if you need special options.
|
|
*/
|
|
|
|
extern int compress __P((Byte *dest, uLong *destLen,
|
|
Byte *source, uLong sourceLen));
|
|
/*
|
|
Compresses the source buffer into the destination buffer. sourceLen is
|
|
the byte length of the source buffer. Upon entry, destLen is the total
|
|
size of the destination buffer, which must be at least 0.1% larger than
|
|
sourceLen plus 12 bytes. Upon exit, destLen is the actual size of the
|
|
compressed buffer.
|
|
This function can be used to compress a whole file at once if the
|
|
input file is mmap'ed.
|
|
compress returns Z_OK if success, Z_MEM_ERROR if there was not
|
|
enough memory, Z_BUF_ERROR if there was not enough room in the output
|
|
buffer.
|
|
*/
|
|
|
|
extern int uncompress __P((Byte *dest, uLong *destLen,
|
|
Byte *source, uLong sourceLen));
|
|
/*
|
|
Decompresses the source buffer into the destination buffer. sourceLen is
|
|
the byte length of the source buffer. Upon entry, destLen is the total
|
|
size of the destination buffer, which must be large enough to hold the
|
|
entire uncompressed data. (The size of the uncompressed data must have
|
|
been saved previously by the compressor and transmitted to the decompressor
|
|
by some mechanism outside the scope of this compression library.)
|
|
Upon exit, destLen is the actual size of the compressed buffer.
|
|
This function can be used to decompress a whole file at once if the
|
|
input file is mmap'ed.
|
|
|
|
uncompress returns Z_OK if success, Z_MEM_ERROR if there was not
|
|
enough memory, Z_BUF_ERROR if there was not enough room in the output
|
|
buffer, or Z_DATA_ERROR if the input data was corrupted.
|
|
*/
|
|
|
|
|
|
typedef voidp gzFile;
|
|
|
|
extern gzFile gzopen __P((char *path, char *mode));
|
|
/*
|
|
Opens a gzip (.gz) file for reading or writing. The mode parameter
|
|
is as in fopen ("rb" or "wb"). gzopen can also be used to read a file
|
|
which is not in gzip format; in this case gzread will directly read from
|
|
the file without decompression.
|
|
gzopen returns NULL if the file could not be opened or if there was
|
|
insufficient memory to allocate the (de)compression state; errno
|
|
can be checked to distinguish the two cases (if errno is zero, the
|
|
zlib error is Z_MEM_ERROR).
|
|
*/
|
|
|
|
extern gzFile gzdopen __P((int fd, char *mode));
|
|
/*
|
|
gzdopen() associates a gzFile with the file descriptor fd. File
|
|
descriptors are obtained from calls like open, dup, creat, or pipe.
|
|
The mode parameter is as in fopen ("rb" or "wb").
|
|
gzdopen returns NULL if there was insufficient memory to allocate
|
|
the (de)compression state.
|
|
*/
|
|
|
|
extern int gzread __P((gzFile file, voidp buf, unsigned len));
|
|
/*
|
|
Reads the given number of uncompressed bytes from the compressed file.
|
|
If the input file was not in gzip format, gzread copies the given number
|
|
of bytes into the buffer.
|
|
gzread returns the number of uncompressed bytes actually read (0 for
|
|
end of file, -1 for error). */
|
|
|
|
extern int gzwrite __P((gzFile file, voidp buf, unsigned len));
|
|
/*
|
|
Writes the given number of uncompressed bytes into the compressed file.
|
|
gzwrite returns the number of uncompressed bytes actually written
|
|
(0 in case of error).
|
|
*/
|
|
|
|
extern int gzflush __P((gzFile file, int flush));
|
|
/*
|
|
Flushes all pending output into the compressed file. The parameter
|
|
flush is as in the deflate() function. The return value is the zlib
|
|
error number (see function gzerror below). gzflush returns Z_OK if
|
|
the flush parameter is Z_FINISH and all output could be flushed.
|
|
gzflush should be called only when strictly necessary because it can
|
|
degrade compression.
|
|
*/
|
|
|
|
extern int gzclose __P((gzFile file));
|
|
/*
|
|
Flushes all pending output if necessary, closes the compressed file
|
|
and deallocates all the (de)compression state. The return value is the zlib
|
|
error number (see function gzerror below).
|
|
*/
|
|
|
|
extern char* gzerror __P((gzFile file, int *errnum));
|
|
/*
|
|
Returns the error message for the last error which occurred on the
|
|
given compressed file. errnum is set to zlib error number. If an
|
|
error occurred in the file system and not in the compression library,
|
|
errnum is set to Z_ERRNO and the application may consult errno
|
|
to get the exact error code.
|
|
*/
|
|
|
|
/* checksum functions */
|
|
|
|
/*
|
|
These functions are not related to compression but are exported
|
|
anyway because they might be useful in applications using the
|
|
compression library.
|
|
*/
|
|
|
|
extern uLong adler32 __P((uLong adler, Byte ZL_FAR *buf, uInt len));
|
|
/*
|
|
Update a running Adler-32 checksum with the bytes buf[0..len-1] and
|
|
return the updated checksum. If buf is NULL, this function returns
|
|
the required initial value for the checksum.
|
|
An Adler-32 checksum is almost as reliable as a CRC32 but can be computed
|
|
much faster. Usage example:
|
|
|
|
uLong adler = adler32(0L, Z_NULL, 0);
|
|
|
|
while (read_buffer(buffer, length) != EOF) {
|
|
adler = adler32(adler, buffer, length);
|
|
}
|
|
if (adler != original_adler) error();
|
|
*/
|
|
|
|
extern uLong crc32 __P((uLong crc, Byte ZL_FAR *buf, uInt len));
|
|
/*
|
|
Update a running crc with the bytes buf[0..len-1] and return the updated
|
|
crc. If buf is NULL, this function returns the required initial value
|
|
for the crc. Pre- and post-conditioning (one's complement) is performed
|
|
within this function so it shouldn't be done by the application.
|
|
Usage example:
|
|
|
|
uLong crc = crc32(0L, Z_NULL, 0);
|
|
|
|
while (read_buffer(buffer, length) != EOF) {
|
|
crc = crc32(crc, buffer, length);
|
|
}
|
|
if (crc != original_crc) error();
|
|
*/
|
|
|
|
#ifndef _Z_UTIL_H
|
|
/*
|
|
* Let's try nuking this def
|
|
*
|
|
* struct internal_state {int dummy;};
|
|
*/
|
|
#endif
|
|
|
|
#endif /* _ZLIB_H */
|