patch-2.1.67 linux/drivers/net/zlib.h
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- Lines: 1011
- Date:
Sat Nov 29 10:33:20 1997
- Orig file:
v2.1.66/linux/drivers/net/zlib.h
- Orig date:
Wed Dec 31 16:00:00 1969
diff -u --recursive --new-file v2.1.66/linux/drivers/net/zlib.h linux/drivers/net/zlib.h
@@ -0,0 +1,1010 @@
+/* $Id: zlib.h,v 1.1 1997/10/02 02:35:37 paulus Exp $ */
+
+/*
+ * This file is derived from zlib.h and zconf.h from the zlib-0.95
+ * distribution by Jean-loup Gailly and Mark Adler, with some additions
+ * by Paul Mackerras to aid in implementing Deflate compression and
+ * decompression for PPP packets.
+ */
+
+/*
+ * ==FILEVERSION 970501==
+ *
+ * This marker is used by the Linux installation script to determine
+ * whether an up-to-date version of this file is already installed.
+ */
+
+
+/* +++ zlib.h */
+/* zlib.h -- interface of the 'zlib' general purpose compression library
+ version 1.0.4, Jul 24th, 1996.
+
+ Copyright (C) 1995-1996 Jean-loup Gailly and Mark Adler
+
+ This software is provided 'as-is', without any express or implied
+ warranty. In no event will the authors be held liable for any damages
+ arising from the use of this software.
+
+ Permission is granted to anyone to use this software for any purpose,
+ including commercial applications, and to alter it and redistribute it
+ freely, subject to the following restrictions:
+
+ 1. The origin of this software must not be misrepresented; you must not
+ claim that you wrote the original software. If you use this software
+ in a product, an acknowledgment in the product documentation would be
+ appreciated but is not required.
+ 2. Altered source versions must be plainly marked as such, and must not be
+ misrepresented as being the original software.
+ 3. This notice may not be removed or altered from any source distribution.
+
+ Jean-loup Gailly Mark Adler
+ gzip@prep.ai.mit.edu madler@alumni.caltech.edu
+
+
+ The data format used by the zlib library is described by RFCs (Request for
+ Comments) 1950 to 1952 in the files ftp://ds.internic.net/rfc/rfc1950.txt
+ (zlib format), rfc1951.txt (deflate format) and rfc1952.txt (gzip format).
+*/
+
+#ifndef _ZLIB_H
+#define _ZLIB_H
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+
+/* +++ zconf.h */
+/* zconf.h -- configuration of the zlib compression library
+ * Copyright (C) 1995-1996 Jean-loup Gailly.
+ * For conditions of distribution and use, see copyright notice in zlib.h
+ */
+
+/* From: zconf.h,v 1.20 1996/07/02 15:09:28 me Exp $ */
+
+#ifndef _ZCONF_H
+#define _ZCONF_H
+
+/*
+ * If you *really* need a unique prefix for all types and library functions,
+ * compile with -DZ_PREFIX. The "standard" zlib should be compiled without it.
+ */
+#ifdef Z_PREFIX
+# define deflateInit_ z_deflateInit_
+# define deflate z_deflate
+# define deflateEnd z_deflateEnd
+# define inflateInit_ z_inflateInit_
+# define inflate z_inflate
+# define inflateEnd z_inflateEnd
+# define deflateInit2_ z_deflateInit2_
+# define deflateSetDictionary z_deflateSetDictionary
+# define deflateCopy z_deflateCopy
+# define deflateReset z_deflateReset
+# define deflateParams z_deflateParams
+# define inflateInit2_ z_inflateInit2_
+# define inflateSetDictionary z_inflateSetDictionary
+# define inflateSync z_inflateSync
+# define inflateReset z_inflateReset
+# define compress z_compress
+# define uncompress z_uncompress
+# define adler32 z_adler32
+# define crc32 z_crc32
+# define get_crc_table z_get_crc_table
+
+# define Byte z_Byte
+# define uInt z_uInt
+# define uLong z_uLong
+# define Bytef z_Bytef
+# define charf z_charf
+# define intf z_intf
+# define uIntf z_uIntf
+# define uLongf z_uLongf
+# define voidpf z_voidpf
+# define voidp z_voidp
+#endif
+
+#if (defined(_WIN32) || defined(__WIN32__)) && !defined(WIN32)
+# define WIN32
+#endif
+#if defined(__GNUC__) || defined(WIN32) || defined(__386__) || defined(i386)
+# ifndef __32BIT__
+# define __32BIT__
+# endif
+#endif
+#if defined(__MSDOS__) && !defined(MSDOS)
+# define MSDOS
+#endif
+
+/*
+ * Compile with -DMAXSEG_64K if the alloc function cannot allocate more
+ * than 64k bytes at a time (needed on systems with 16-bit int).
+ */
+#if defined(MSDOS) && !defined(__32BIT__)
+# define MAXSEG_64K
+#endif
+#ifdef MSDOS
+# define UNALIGNED_OK
+#endif
+
+#if (defined(MSDOS) || defined(_WINDOWS) || defined(WIN32)) && !defined(STDC)
+# define STDC
+#endif
+#if (defined(__STDC__) || defined(__cplusplus)) && !defined(STDC)
+# define STDC
+#endif
+
+#ifndef STDC
+# ifndef const /* cannot use !defined(STDC) && !defined(const) on Mac */
+# define const
+# endif
+#endif
+
+/* Some Mac compilers merge all .h files incorrectly: */
+#if defined(__MWERKS__) || defined(applec) ||defined(THINK_C) ||defined(__SC__)
+# define NO_DUMMY_DECL
+#endif
+
+/* Maximum value for memLevel in deflateInit2 */
+#ifndef MAX_MEM_LEVEL
+# ifdef MAXSEG_64K
+# define MAX_MEM_LEVEL 8
+# else
+# define MAX_MEM_LEVEL 9
+# endif
+#endif
+
+/* Maximum value for windowBits in deflateInit2 and inflateInit2 */
+#ifndef MAX_WBITS
+# define MAX_WBITS 15 /* 32K LZ77 window */
+#endif
+
+/* The memory requirements for deflate are (in bytes):
+ 1 << (windowBits+2) + 1 << (memLevel+9)
+ that is: 128K for windowBits=15 + 128K for memLevel = 8 (default values)
+ plus a few kilobytes for small objects. For example, if you want to reduce
+ the default memory requirements from 256K to 128K, compile with
+ make CFLAGS="-O -DMAX_WBITS=14 -DMAX_MEM_LEVEL=7"
+ Of course this will generally degrade compression (there's no free lunch).
+
+ The memory requirements for inflate are (in bytes) 1 << windowBits
+ that is, 32K for windowBits=15 (default value) plus a few kilobytes
+ for small objects.
+*/
+
+ /* Type declarations */
+
+#ifndef OF /* function prototypes */
+# ifdef STDC
+# define OF(args) args
+# else
+# define OF(args) ()
+# endif
+#endif
+
+/* The following definitions for FAR are needed only for MSDOS mixed
+ * model programming (small or medium model with some far allocations).
+ * This was tested only with MSC; for other MSDOS compilers you may have
+ * to define NO_MEMCPY in zutil.h. If you don't need the mixed model,
+ * just define FAR to be empty.
+ */
+#if (defined(M_I86SM) || defined(M_I86MM)) && !defined(__32BIT__)
+ /* MSC small or medium model */
+# define SMALL_MEDIUM
+# ifdef _MSC_VER
+# define FAR __far
+# else
+# define FAR far
+# endif
+#endif
+#if defined(__BORLANDC__) && (defined(__SMALL__) || defined(__MEDIUM__))
+# ifndef __32BIT__
+# define SMALL_MEDIUM
+# define FAR __far
+# endif
+#endif
+#ifndef FAR
+# define FAR
+#endif
+
+typedef unsigned char Byte; /* 8 bits */
+typedef unsigned int uInt; /* 16 bits or more */
+typedef unsigned long uLong; /* 32 bits or more */
+
+#if defined(__BORLANDC__) && defined(SMALL_MEDIUM)
+ /* Borland C/C++ ignores FAR inside typedef */
+# define Bytef Byte FAR
+#else
+ typedef Byte FAR Bytef;
+#endif
+typedef char FAR charf;
+typedef int FAR intf;
+typedef uInt FAR uIntf;
+typedef uLong FAR uLongf;
+
+#ifdef STDC
+ typedef void FAR *voidpf;
+ typedef void *voidp;
+#else
+ typedef Byte FAR *voidpf;
+ typedef Byte *voidp;
+#endif
+
+
+/* Compile with -DZLIB_DLL for Windows DLL support */
+#if (defined(_WINDOWS) || defined(WINDOWS)) && defined(ZLIB_DLL)
+# include <windows.h>
+# define EXPORT WINAPI
+#else
+# define EXPORT
+#endif
+
+#endif /* _ZCONF_H */
+/* --- zconf.h */
+
+#define ZLIB_VERSION "1.0.4P"
+
+/*
+ The 'zlib' compression library provides in-memory compression and
+ decompression functions, including integrity checks of the uncompressed
+ data. This version of the library supports only one compression method
+ (deflation) but other algorithms may be added later and will have the same
+ stream interface.
+
+ For compression the application must provide the output buffer and
+ may optionally provide the input buffer for optimization. For decompression,
+ the application must provide the input buffer and may optionally provide
+ the output buffer for optimization.
+
+ Compression can be done in a single step if the buffers are large
+ enough (for example if an input file is mmap'ed), or can be done by
+ repeated calls of the compression function. In the latter case, the
+ application must provide more input and/or consume the output
+ (providing more output space) before each call.
+
+ The library does not install any signal handler. It is recommended to
+ add at least a handler for SIGSEGV when decompressing; the library checks
+ the consistency of the input data whenever possible but may go nuts
+ for some forms of corrupted input.
+*/
+
+typedef voidpf (*alloc_func) OF((voidpf opaque, uInt items, uInt size));
+typedef void (*free_func) OF((voidpf opaque, voidpf address));
+
+struct internal_state;
+
+typedef struct z_stream_s {
+ Bytef *next_in; /* next input byte */
+ uInt avail_in; /* number of bytes available at next_in */
+ uLong total_in; /* total nb of input bytes read so far */
+
+ Bytef *next_out; /* next output byte should be put there */
+ uInt avail_out; /* remaining free space at next_out */
+ uLong total_out; /* total nb of bytes output so far */
+
+ char *msg; /* last error message, NULL if no error */
+ struct internal_state FAR *state; /* not visible by applications */
+
+ alloc_func zalloc; /* used to allocate the internal state */
+ free_func zfree; /* used to free the internal state */
+ voidpf opaque; /* private data object passed to zalloc and zfree */
+
+ int data_type; /* best guess about the data type: ascii or binary */
+ uLong adler; /* adler32 value of the uncompressed data */
+ uLong reserved; /* reserved for future use */
+} z_stream;
+
+typedef z_stream FAR *z_streamp;
+
+/*
+ The application must update next_in and avail_in when avail_in has
+ dropped to zero. It must update next_out and avail_out when avail_out
+ has dropped to zero. The application must initialize zalloc, zfree and
+ opaque before calling the init function. All other fields are set by the
+ compression library and must not be updated by the application.
+
+ The opaque value provided by the application will be passed as the first
+ parameter for calls of zalloc and zfree. This can be useful for custom
+ memory management. The compression library attaches no meaning to the
+ opaque value.
+
+ zalloc must return Z_NULL if there is not enough memory for the object.
+ On 16-bit systems, the functions zalloc and zfree must be able to allocate
+ exactly 65536 bytes, but will not be required to allocate more than this
+ if the symbol MAXSEG_64K is defined (see zconf.h). WARNING: On MSDOS,
+ pointers returned by zalloc for objects of exactly 65536 bytes *must*
+ have their offset normalized to zero. The default allocation function
+ provided by this library ensures this (see zutil.c). To reduce memory
+ requirements and avoid any allocation of 64K objects, at the expense of
+ compression ratio, compile the library with -DMAX_WBITS=14 (see zconf.h).
+
+ The fields total_in and total_out can be used for statistics or
+ progress reports. After compression, total_in holds the total size of
+ the uncompressed data and may be saved for use in the decompressor
+ (particularly if the decompressor wants to decompress everything in
+ a single step).
+*/
+
+ /* constants */
+
+#define Z_NO_FLUSH 0
+#define Z_PARTIAL_FLUSH 1
+#define Z_PACKET_FLUSH 2
+#define Z_SYNC_FLUSH 3
+#define Z_FULL_FLUSH 4
+#define Z_FINISH 5
+/* Allowed flush values; see deflate() below for details */
+
+#define Z_OK 0
+#define Z_STREAM_END 1
+#define Z_NEED_DICT 2
+#define Z_ERRNO (-1)
+#define Z_STREAM_ERROR (-2)
+#define Z_DATA_ERROR (-3)
+#define Z_MEM_ERROR (-4)
+#define Z_BUF_ERROR (-5)
+#define Z_VERSION_ERROR (-6)
+/* Return codes for the compression/decompression functions. Negative
+ * values are errors, positive values are used for special but normal events.
+ */
+
+#define Z_NO_COMPRESSION 0
+#define Z_BEST_SPEED 1
+#define Z_BEST_COMPRESSION 9
+#define Z_DEFAULT_COMPRESSION (-1)
+/* compression levels */
+
+#define Z_FILTERED 1
+#define Z_HUFFMAN_ONLY 2
+#define Z_DEFAULT_STRATEGY 0
+/* compression strategy; see deflateInit2() below for details */
+
+#define Z_BINARY 0
+#define Z_ASCII 1
+#define Z_UNKNOWN 2
+/* Possible values of the data_type field */
+
+#define Z_DEFLATED 8
+/* The deflate compression method (the only one supported in this version) */
+
+#define Z_NULL 0 /* for initializing zalloc, zfree, opaque */
+
+#define zlib_version zlibVersion()
+/* for compatibility with versions < 1.0.2 */
+
+ /* basic functions */
+
+extern const char * EXPORT zlibVersion OF((void));
+/* The application can compare zlibVersion and ZLIB_VERSION for consistency.
+ If the first character differs, the library code actually used is
+ not compatible with the zlib.h header file used by the application.
+ This check is automatically made by deflateInit and inflateInit.
+ */
+
+/*
+extern int EXPORT deflateInit OF((z_streamp strm, int level));
+
+ Initializes the internal stream state for compression. The fields
+ zalloc, zfree and opaque must be initialized before by the caller.
+ If zalloc and zfree are set to Z_NULL, deflateInit updates them to
+ use default allocation functions.
+
+ The compression level must be Z_DEFAULT_COMPRESSION, or between 0 and 9:
+ 1 gives best speed, 9 gives best compression, 0 gives no compression at
+ all (the input data is simply copied a block at a time).
+ Z_DEFAULT_COMPRESSION requests a default compromise between speed and
+ compression (currently equivalent to level 6).
+
+ deflateInit returns Z_OK if success, Z_MEM_ERROR if there was not
+ enough memory, Z_STREAM_ERROR if level is not a valid compression level,
+ Z_VERSION_ERROR if the zlib library version (zlib_version) is incompatible
+ with the version assumed by the caller (ZLIB_VERSION).
+ msg is set to null if there is no error message. deflateInit does not
+ perform any compression: this will be done by deflate().
+*/
+
+
+extern int EXPORT deflate OF((z_streamp strm, int flush));
+/*
+ Performs one or both of the following actions:
+
+ - Compress more input starting at next_in and update next_in and avail_in
+ accordingly. If not all input can be processed (because there is not
+ enough room in the output buffer), next_in and avail_in are updated and
+ processing will resume at this point for the next call of deflate().
+
+ - Provide more output starting at next_out and update next_out and avail_out
+ accordingly. This action is forced if the parameter flush is non zero.
+ Forcing flush frequently degrades the compression ratio, so this parameter
+ should be set only when necessary (in interactive applications).
+ Some output may be provided even if flush is not set.
+
+ Before the call of deflate(), the application should ensure that at least
+ one of the actions is possible, by providing more input and/or consuming
+ more output, and updating avail_in or avail_out accordingly; avail_out
+ should never be zero before the call. The application can consume the
+ compressed output when it wants, for example when the output buffer is full
+ (avail_out == 0), or after each call of deflate(). If deflate returns Z_OK
+ and with zero avail_out, it must be called again after making room in the
+ output buffer because there might be more output pending.
+
+ If the parameter flush is set to Z_PARTIAL_FLUSH, the current compression
+ block is terminated and flushed to the output buffer so that the
+ decompressor can get all input data available so far. For method 9, a future
+ variant on method 8, the current block will be flushed but not terminated.
+ Z_SYNC_FLUSH has the same effect as partial flush except that the compressed
+ output is byte aligned (the compressor can clear its internal bit buffer)
+ and the current block is always terminated; this can be useful if the
+ compressor has to be restarted from scratch after an interruption (in which
+ case the internal state of the compressor may be lost).
+ If flush is set to Z_FULL_FLUSH, the compression block is terminated, a
+ special marker is output and the compression dictionary is discarded; this
+ is useful to allow the decompressor to synchronize if one compressed block
+ has been damaged (see inflateSync below). Flushing degrades compression and
+ so should be used only when necessary. Using Z_FULL_FLUSH too often can
+ seriously degrade the compression. If deflate returns with avail_out == 0,
+ this function must be called again with the same value of the flush
+ parameter and more output space (updated avail_out), until the flush is
+ complete (deflate returns with non-zero avail_out).
+
+ If the parameter flush is set to Z_PACKET_FLUSH, the compression
+ block is terminated, and a zero-length stored block is output,
+ omitting the length bytes (the effect of this is that the 3-bit type
+ code 000 for a stored block is output, and the output is then
+ byte-aligned). This is designed for use at the end of a PPP packet.
+
+ If the parameter flush is set to Z_FINISH, pending input is processed,
+ pending output is flushed and deflate returns with Z_STREAM_END if there
+ was enough output space; if deflate returns with Z_OK, this function must be
+ called again with Z_FINISH and more output space (updated avail_out) but no
+ more input data, until it returns with Z_STREAM_END or an error. After
+ deflate has returned Z_STREAM_END, the only possible operations on the
+ stream are deflateReset or deflateEnd.
+
+ Z_FINISH can be used immediately after deflateInit if all the compression
+ is to be done in a single step. In this case, avail_out must be at least
+ 0.1% larger than avail_in plus 12 bytes. If deflate does not return
+ Z_STREAM_END, then it must be called again as described above.
+
+ deflate() may update data_type if it can make a good guess about
+ the input data type (Z_ASCII or Z_BINARY). In doubt, the data is considered
+ binary. This field is only for information purposes and does not affect
+ the compression algorithm in any manner.
+
+ deflate() returns Z_OK if some progress has been made (more input
+ processed or more output produced), Z_STREAM_END if all input has been
+ consumed and all output has been produced (only when flush is set to
+ Z_FINISH), Z_STREAM_ERROR if the stream state was inconsistent (for example
+ if next_in or next_out was NULL), Z_BUF_ERROR if no progress is possible.
+*/
+
+
+extern int EXPORT deflateEnd OF((z_streamp strm));
+/*
+ All dynamically allocated data structures for this stream are freed.
+ This function discards any unprocessed input and does not flush any
+ pending output.
+
+ deflateEnd returns Z_OK if success, Z_STREAM_ERROR if the
+ stream state was inconsistent, Z_DATA_ERROR if the stream was freed
+ prematurely (some input or output was discarded). In the error case,
+ msg may be set but then points to a static string (which must not be
+ deallocated).
+*/
+
+
+/*
+extern int EXPORT inflateInit OF((z_streamp strm));
+
+ Initializes the internal stream state for decompression. The fields
+ zalloc, zfree and opaque must be initialized before by the caller. If
+ zalloc and zfree are set to Z_NULL, inflateInit updates them to use default
+ allocation functions.
+
+ inflateInit returns Z_OK if success, Z_MEM_ERROR if there was not
+ enough memory, Z_VERSION_ERROR if the zlib library version is incompatible
+ with the version assumed by the caller. msg is set to null if there is no
+ error message. inflateInit does not perform any decompression: this will be
+ done by inflate().
+*/
+
+
+extern int EXPORT inflate OF((z_streamp strm, int flush));
+/*
+ Performs one or both of the following actions:
+
+ - Decompress more input starting at next_in and update next_in and avail_in
+ accordingly. If not all input can be processed (because there is not
+ enough room in the output buffer), next_in is updated and processing
+ will resume at this point for the next call of inflate().
+
+ - Provide more output starting at next_out and update next_out and avail_out
+ accordingly. inflate() provides as much output as possible, until there
+ is no more input data or no more space in the output buffer (see below
+ about the flush parameter).
+
+ Before the call of inflate(), the application should ensure that at least
+ one of the actions is possible, by providing more input and/or consuming
+ more output, and updating the next_* and avail_* values accordingly.
+ The application can consume the uncompressed output when it wants, for
+ example when the output buffer is full (avail_out == 0), or after each
+ call of inflate(). If inflate returns Z_OK and with zero avail_out, it
+ must be called again after making room in the output buffer because there
+ might be more output pending.
+
+ If the parameter flush is set to Z_PARTIAL_FLUSH or Z_PACKET_FLUSH,
+ inflate flushes as much output as possible to the output buffer. The
+ flushing behavior of inflate is not specified for values of the flush
+ parameter other than Z_PARTIAL_FLUSH, Z_PACKET_FLUSH or Z_FINISH, but the
+ current implementation actually flushes as much output as possible
+ anyway. For Z_PACKET_FLUSH, inflate checks that once all the input data
+ has been consumed, it is expecting to see the length field of a stored
+ block; if not, it returns Z_DATA_ERROR.
+
+ inflate() should normally be called until it returns Z_STREAM_END or an
+ error. However if all decompression is to be performed in a single step
+ (a single call of inflate), the parameter flush should be set to
+ Z_FINISH. In this case all pending input is processed and all pending
+ output is flushed; avail_out must be large enough to hold all the
+ uncompressed data. (The size of the uncompressed data may have been saved
+ by the compressor for this purpose.) The next operation on this stream must
+ be inflateEnd to deallocate the decompression state. The use of Z_FINISH
+ is never required, but can be used to inform inflate that a faster routine
+ may be used for the single inflate() call.
+
+ inflate() returns Z_OK if some progress has been made (more input
+ processed or more output produced), Z_STREAM_END if the end of the
+ compressed data has been reached and all uncompressed output has been
+ produced, Z_NEED_DICT if a preset dictionary is needed at this point (see
+ inflateSetDictionary below), Z_DATA_ERROR if the input data was corrupted,
+ Z_STREAM_ERROR if the stream structure was inconsistent (for example if
+ next_in or next_out was NULL), Z_MEM_ERROR if there was not enough memory,
+ Z_BUF_ERROR if no progress is possible or if there was not enough room in
+ the output buffer when Z_FINISH is used. In the Z_DATA_ERROR case, the
+ application may then call inflateSync to look for a good compression block.
+ In the Z_NEED_DICT case, strm->adler is set to the Adler32 value of the
+ dictionary chosen by the compressor.
+*/
+
+
+extern int EXPORT inflateEnd OF((z_streamp strm));
+/*
+ All dynamically allocated data structures for this stream are freed.
+ This function discards any unprocessed input and does not flush any
+ pending output.
+
+ inflateEnd returns Z_OK if success, Z_STREAM_ERROR if the stream state
+ was inconsistent. In the error case, msg may be set but then points to a
+ static string (which must not be deallocated).
+*/
+
+ /* Advanced functions */
+
+/*
+ The following functions are needed only in some special applications.
+*/
+
+/*
+extern int EXPORT deflateInit2 OF((z_streamp strm,
+ int level,
+ int method,
+ int windowBits,
+ int memLevel,
+ int strategy));
+
+ This is another version of deflateInit with more compression options. The
+ fields next_in, zalloc, zfree and opaque must be initialized before by
+ the caller.
+
+ The method parameter is the compression method. It must be Z_DEFLATED in
+ this version of the library. (Method 9 will allow a 64K history buffer and
+ partial block flushes.)
+
+ The windowBits parameter is the base two logarithm of the window size
+ (the size of the history buffer). It should be in the range 8..15 for this
+ version of the library (the value 16 will be allowed for method 9). Larger
+ values of this parameter result in better compression at the expense of
+ memory usage. The default value is 15 if deflateInit is used instead.
+
+ The memLevel parameter specifies how much memory should be allocated
+ for the internal compression state. memLevel=1 uses minimum memory but
+ is slow and reduces compression ratio; memLevel=9 uses maximum memory
+ for optimal speed. The default value is 8. See zconf.h for total memory
+ usage as a function of windowBits and memLevel.
+
+ The strategy parameter is used to tune the compression algorithm. Use the
+ value Z_DEFAULT_STRATEGY for normal data, Z_FILTERED for data produced by a
+ filter (or predictor), or Z_HUFFMAN_ONLY to force Huffman encoding only (no
+ string match). Filtered data consists mostly of small values with a
+ 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.
+
+ If next_in is not null, the library will use this buffer to hold also
+ some history information; the buffer must either hold the entire input
+ data, or have at least 1<<(windowBits+1) bytes and be writable. If next_in
+ is null, the library will allocate its own history buffer (and leave next_in
+ null). next_out need not be provided here but must be provided by the
+ application for the next call of deflate().
+
+ If the history buffer is provided by the application, next_in must
+ must never be changed by the application since the compressor maintains
+ information inside this buffer from call to call; the application
+ must provide more input only by increasing avail_in. next_in is always
+ reset by the library in this case.
+
+ 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 EXPORT deflateSetDictionary OF((z_streamp strm,
+ const Bytef *dictionary,
+ uInt dictLength));
+/*
+ Initializes the compression dictionary (history buffer) from the given
+ byte sequence without producing any compressed output. This function must
+ be called immediately after deflateInit or deflateInit2, before any call
+ of deflate. The compressor and decompressor must use exactly the same
+ dictionary (see inflateSetDictionary).
+ The dictionary should consist of strings (byte sequences) that are likely
+ to be encountered later in the data to be compressed, with the most commonly
+ used strings preferably put towards the end of the dictionary. Using a
+ dictionary is most useful when the data to be compressed is short and
+ can be predicted with good accuracy; the data can then be compressed better
+ than with the default empty dictionary. In this version of the library,
+ only the last 32K bytes of the dictionary are used.
+ Upon return of this function, strm->adler is set to the Adler32 value
+ of the dictionary; the decompressor may later use this value to determine
+ which dictionary has been used by the compressor. (The Adler32 value
+ applies to the whole dictionary even if only a subset of the dictionary is
+ actually used by the compressor.)
+
+ deflateSetDictionary returns Z_OK if success, or Z_STREAM_ERROR if a
+ parameter is invalid (such as NULL dictionary) or the stream state
+ is inconsistent (for example if deflate has already been called for this
+ stream). deflateSetDictionary does not perform any compression: this will
+ be done by deflate().
+*/
+
+extern int EXPORT deflateCopy OF((z_streamp dest,
+ z_streamp source));
+/*
+ Sets the destination stream as a complete copy of the source stream. If
+ the source stream is using an application-supplied history buffer, a new
+ buffer is allocated for the destination stream. The compressed output
+ buffer is always application-supplied. It's the responsibility of the
+ application to provide the correct values of next_out and avail_out for the
+ next call of deflate.
+
+ This function can be useful when several compression strategies will be
+ tried, for example when there are several ways of pre-processing the input
+ data with a filter. The streams that will be discarded should then be freed
+ by calling deflateEnd. Note that deflateCopy duplicates the internal
+ compression state which can be quite large, so this strategy is slow and
+ can consume lots of memory.
+
+ deflateCopy returns Z_OK if success, Z_MEM_ERROR if there was not
+ enough memory, Z_STREAM_ERROR if the source stream state was inconsistent
+ (such as zalloc being NULL). msg is left unchanged in both source and
+ destination.
+*/
+
+extern int EXPORT deflateReset OF((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).
+*/
+
+extern int EXPORT deflateParams OF((z_streamp strm, int level, int strategy));
+/*
+ Dynamically update the compression level and compression strategy.
+ This can be used to switch between compression and straight copy of
+ the input data, or to switch to a different kind of input data requiring
+ a different strategy. If the compression level is changed, the input
+ available so far is compressed with the old level (and may be flushed);
+ the new level will take effect only at the next call of deflate().
+
+ Before the call of deflateParams, the stream state must be set as for
+ a call of deflate(), since the currently available input may have to
+ be compressed and flushed. In particular, strm->avail_out must be non-zero.
+
+ deflateParams returns Z_OK if success, Z_STREAM_ERROR if the source
+ stream state was inconsistent or if a parameter was invalid, Z_BUF_ERROR
+ if strm->avail_out was zero.
+*/
+
+extern int EXPORT deflateOutputPending OF((z_streamp strm));
+/*
+ Returns the number of bytes of output which are immediately
+ available from the compressor (i.e. without any further input
+ or flush).
+*/
+
+/*
+extern int EXPORT inflateInit2 OF((z_streamp strm,
+ int windowBits));
+
+ This is another version of inflateInit with more compression options. The
+ fields next_out, 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 value 16 will be allowed soon). The
+ default value is 15 if inflateInit is used instead. 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.
+
+ If next_out is not null, the library will use this buffer for the history
+ buffer; the buffer must either be large enough to hold the entire output
+ data, or have at least 1<<windowBits bytes. If next_out is null, the
+ library will allocate its own buffer (and leave next_out null). next_in
+ need not be provided here but must be provided by the application for the
+ next call of inflate().
+
+ If the history buffer is provided by the application, next_out must
+ never be changed by the application since the decompressor maintains
+ history information inside this buffer from call to call; the application
+ can only reset next_out to the beginning of the history buffer when
+ avail_out is zero and all output has been consumed.
+
+ 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
+ windowBits < 8). msg is set to null if there is no error message.
+ inflateInit2 does not perform any decompression: this will be done by
+ inflate().
+*/
+
+extern int EXPORT inflateSetDictionary OF((z_streamp strm,
+ const Bytef *dictionary,
+ uInt dictLength));
+/*
+ Initializes the decompression dictionary (history buffer) from the given
+ uncompressed byte sequence. This function must be called immediately after
+ a call of inflate if this call returned Z_NEED_DICT. The dictionary chosen
+ by the compressor can be determined from the Adler32 value returned by this
+ call of inflate. The compressor and decompressor must use exactly the same
+ dictionary (see deflateSetDictionary).
+
+ inflateSetDictionary returns Z_OK if success, Z_STREAM_ERROR if a
+ parameter is invalid (such as NULL dictionary) or the stream state is
+ inconsistent, Z_DATA_ERROR if the given dictionary doesn't match the
+ expected one (incorrect Adler32 value). inflateSetDictionary does not
+ perform any decompression: this will be done by subsequent calls of
+ inflate().
+*/
+
+extern int EXPORT inflateSync OF((z_streamp strm));
+/*
+ Skips invalid compressed data until the special marker (see deflate()
+ above) can be found, or until all available input is skipped. No output
+ is provided.
+
+ inflateSync returns Z_OK if the special marker has been found, Z_BUF_ERROR
+ if no more input was provided, Z_DATA_ERROR if no marker has been found,
+ or Z_STREAM_ERROR if the stream structure was inconsistent. In the success
+ case, the application may save the current current value of total_in which
+ 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 EXPORT inflateReset OF((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 inflateIncomp OF((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).
+*/
+
+ /* 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 EXPORT compress OF((Bytef *dest, uLongf *destLen,
+ const Bytef *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 EXPORT uncompress OF((Bytef *dest, uLongf *destLen,
+ const Bytef *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 EXPORT gzopen OF((const char *path, const char *mode));
+/*
+ Opens a gzip (.gz) file for reading or writing. The mode parameter
+ is as in fopen ("rb" or "wb") but can also include a compression level
+ ("wb9"). gzopen can 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 EXPORT gzdopen OF((int fd, const char *mode));
+/*
+ gzdopen() associates a gzFile with the file descriptor fd. File
+ descriptors are obtained from calls like open, dup, creat, pipe or
+ fileno (in the file has been previously opened with fopen).
+ The mode parameter is as in gzopen.
+ The next call of gzclose on the returned gzFile will also close the
+ file descriptor fd, just like fclose(fdopen(fd), mode) closes the file
+ descriptor fd. If you want to keep fd open, use gzdopen(dup(fd), mode).
+ gzdopen returns NULL if there was insufficient memory to allocate
+ the (de)compression state.
+*/
+
+extern int EXPORT gzread OF((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 EXPORT gzwrite OF((gzFile file, const 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 EXPORT gzflush OF((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 EXPORT gzclose OF((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 const char * EXPORT gzerror OF((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 EXPORT adler32 OF((uLong adler, const Bytef *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 EXPORT crc32 OF((uLong crc, const Bytef *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();
+*/
+
+
+ /* various hacks, don't look :) */
+
+/* deflateInit and inflateInit are macros to allow checking the zlib version
+ * and the compiler's view of z_stream:
+ */
+extern int EXPORT deflateInit_ OF((z_streamp strm, int level,
+ const char *version, int stream_size));
+extern int EXPORT inflateInit_ OF((z_streamp strm,
+ const char *version, int stream_size));
+extern int EXPORT deflateInit2_ OF((z_streamp strm, int level, int method,
+ int windowBits, int memLevel, int strategy,
+ const char *version, int stream_size));
+extern int EXPORT inflateInit2_ OF((z_streamp strm, int windowBits,
+ const char *version, int stream_size));
+#define deflateInit(strm, level) \
+ deflateInit_((strm), (level), ZLIB_VERSION, sizeof(z_stream))
+#define inflateInit(strm) \
+ inflateInit_((strm), ZLIB_VERSION, sizeof(z_stream))
+#define deflateInit2(strm, level, method, windowBits, memLevel, strategy) \
+ deflateInit2_((strm),(level),(method),(windowBits),(memLevel),\
+ (strategy), ZLIB_VERSION, sizeof(z_stream))
+#define inflateInit2(strm, windowBits) \
+ inflateInit2_((strm), (windowBits), ZLIB_VERSION, sizeof(z_stream))
+
+#if !defined(_Z_UTIL_H) && !defined(NO_DUMMY_DECL)
+ struct internal_state {int dummy;}; /* hack for buggy compilers */
+#endif
+
+uLongf *get_crc_table OF((void)); /* can be used by asm versions of crc32() */
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* _ZLIB_H */
+/* --- zlib.h */
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