1913 lines
		
	
	
		
			94 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			1913 lines
		
	
	
		
			94 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /* zlib.h -- interface of the 'zlib' general purpose compression library
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|   version 1.2.11, January 15th, 2017
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| 
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|   Copyright (C) 1995-2017 Jean-loup Gailly and Mark Adler
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| 
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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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| 
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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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| 
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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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| 
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|   Jean-loup Gailly        Mark Adler
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|   jloup@gzip.org          madler@alumni.caltech.edu
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| 
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| 
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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 http://tools.ietf.org/html/rfc1950
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|   (zlib format), rfc1951 (deflate format) and rfc1952 (gzip format).
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| */
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| 
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| #ifndef ZLIB_H
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| #define ZLIB_H
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| 
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| #include "zconf.h"
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| 
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| #ifdef __cplusplus
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| extern "C" {
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| #endif
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| 
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| #define ZLIB_VERSION "1.2.11"
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| #define ZLIB_VERNUM 0x12b0
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| #define ZLIB_VER_MAJOR 1
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| #define ZLIB_VER_MINOR 2
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| #define ZLIB_VER_REVISION 11
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| #define ZLIB_VER_SUBREVISION 0
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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 data.
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|   This version of the library supports only one compression method (deflation)
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|   but other algorithms will be added later and will have the same stream
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|   interface.
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| 
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|     Compression can be done in a single step if the buffers are large enough,
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|   or can be done by repeated calls of the compression function.  In the latter
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|   case, the 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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|     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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| 
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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 using the functions that start
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|   with "gz".  The gzip format is different from the zlib format.  gzip is a
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|   gzip wrapper, documented in RFC 1952, wrapped around a deflate stream.
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| 
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|     This library can optionally read and write gzip and raw deflate streams in
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|   memory as well.
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| 
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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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| 
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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 crash
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|   even in the case of corrupted input.
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| */
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| 
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| typedef voidpf (*alloc_func) OF((voidpf opaque, uInt items, uInt size));
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| typedef void   (*free_func)  OF((voidpf opaque, voidpf address));
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| 
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| struct internal_state;
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| 
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| typedef struct z_stream_s {
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|     z_const Bytef *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 number of input bytes read so far */
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| 
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|     Bytef    *next_out; /* next output byte will go here */
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|     uInt     avail_out; /* remaining free space at next_out */
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|     uLong    total_out; /* total number of bytes output so far */
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| 
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|     z_const char *msg;  /* last error message, NULL if no error */
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|     struct internal_state FAR *state; /* not visible by applications */
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| 
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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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|     voidpf     opaque;  /* private data object passed to zalloc and zfree */
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| 
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|     int     data_type;  /* best guess about the data type: binary or text
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|                            for deflate, or the decoding state for inflate */
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|     uLong   adler;      /* Adler-32 or CRC-32 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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| 
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| typedef z_stream FAR *z_streamp;
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| 
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| /*
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|      gzip header information passed to and from zlib routines.  See RFC 1952
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|   for more details on the meanings of these fields.
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| */
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| typedef struct gz_header_s {
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|     int     text;       /* true if compressed data believed to be text */
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|     uLong   time;       /* modification time */
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|     int     xflags;     /* extra flags (not used when writing a gzip file) */
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|     int     os;         /* operating system */
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|     Bytef   *extra;     /* pointer to extra field or Z_NULL if none */
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|     uInt    extra_len;  /* extra field length (valid if extra != Z_NULL) */
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|     uInt    extra_max;  /* space at extra (only when reading header) */
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|     Bytef   *name;      /* pointer to zero-terminated file name or Z_NULL */
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|     uInt    name_max;   /* space at name (only when reading header) */
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|     Bytef   *comment;   /* pointer to zero-terminated comment or Z_NULL */
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|     uInt    comm_max;   /* space at comment (only when reading header) */
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|     int     hcrc;       /* true if there was or will be a header crc */
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|     int     done;       /* true when done reading gzip header (not used
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|                            when writing a gzip file) */
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| } gz_header;
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| 
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| typedef gz_header FAR *gz_headerp;
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| 
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| /*
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|      The application must update next_in and avail_in when avail_in has dropped
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|    to zero.  It must update next_out and avail_out when avail_out has dropped
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|    to zero.  The application must initialize zalloc, zfree and opaque before
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|    calling the init function.  All other fields are set by the compression
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|    library and must not be updated by the application.
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| 
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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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| 
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|      zalloc must return Z_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.  In that case, zlib is thread-safe.  When zalloc and zfree are
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|    Z_NULL on entry to the initialization function, they are set to internal
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|    routines that use the standard library functions malloc() and free().
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| 
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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 if
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|    the symbol MAXSEG_64K is defined (see zconf.h).  WARNING: On MSDOS, pointers
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|    returned by zalloc for objects of exactly 65536 bytes *must* have their
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|    offset normalized to zero.  The default allocation function provided by this
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|    library ensures this (see zutil.c).  To reduce memory requirements and avoid
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|    any allocation of 64K objects, at the expense of compression ratio, compile
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|    the library with -DMAX_WBITS=14 (see zconf.h).
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| 
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|      The fields total_in and total_out can be used for statistics or progress
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|    reports.  After compression, total_in holds the total size of the
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|    uncompressed data and may be saved for use by the decompressor (particularly
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|    if the decompressor wants to decompress everything in a single step).
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| */
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| 
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|                         /* constants */
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| 
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| #define Z_NO_FLUSH      0
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| #define Z_PARTIAL_FLUSH 1
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| #define Z_SYNC_FLUSH    2
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| #define Z_FULL_FLUSH    3
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| #define Z_FINISH        4
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| #define Z_BLOCK         5
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| #define Z_TREES         6
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| /* Allowed flush values; see deflate() and inflate() below for details */
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| 
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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 values
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|  * are errors, positive values are used for special but normal events.
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|  */
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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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| 
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| #define Z_FILTERED            1
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| #define Z_HUFFMAN_ONLY        2
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| #define Z_RLE                 3
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| #define Z_FIXED               4
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| #define Z_DEFAULT_STRATEGY    0
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| /* compression strategy; see deflateInit2() below for details */
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| 
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| #define Z_BINARY   0
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| #define Z_TEXT     1
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| #define Z_ASCII    Z_TEXT   /* for compatibility with 1.2.2 and earlier */
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| #define Z_UNKNOWN  2
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| /* Possible values of the data_type field for deflate() */
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| 
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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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| 
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| #define Z_NULL  0  /* for initializing zalloc, zfree, opaque */
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| 
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| #define zlib_version zlibVersion()
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| /* for compatibility with versions < 1.0.2 */
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| 
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| 
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|                         /* basic functions */
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| 
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| ZEXTERN const char * ZEXPORT zlibVersion OF((void));
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| /* The application can compare zlibVersion and ZLIB_VERSION for consistency.
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|    If the first character differs, the library code actually used is not
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|    compatible with the zlib.h header file used by the application.  This check
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|    is automatically made by deflateInit and inflateInit.
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|  */
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| 
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| /*
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| ZEXTERN int ZEXPORT deflateInit OF((z_streamp 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.  If
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|    zalloc and zfree are set to Z_NULL, deflateInit updates them to use default
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|    allocation functions.
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| 
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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 all
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|    (the input data is simply copied a block at a time).  Z_DEFAULT_COMPRESSION
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|    requests a default compromise between speed and compression (currently
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|    equivalent to level 6).
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| 
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|      deflateInit returns Z_OK if success, Z_MEM_ERROR if there was not enough
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|    memory, Z_STREAM_ERROR if level is not a valid compression level, or
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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).  msg is set to null
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|    if there is no error message.  deflateInit does not perform any compression:
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|    this will be done by deflate().
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| */
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| 
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| 
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| ZEXTERN int ZEXPORT deflate OF((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
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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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| 
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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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| 
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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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| 
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|   - Generate 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.  Some output may be provided even if
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|     flush is zero.
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| 
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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 more
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|   output, and updating avail_in or avail_out accordingly; avail_out should
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|   never be zero before the call.  The application can consume the compressed
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|   output when it wants, for example when the output buffer is full (avail_out
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|   == 0), or after each call of deflate().  If deflate returns Z_OK and with
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|   zero avail_out, it must be called again after making room in the output
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|   buffer because there might be more output pending. See deflatePending(),
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|   which can be used if desired to determine whether or not there is more ouput
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|   in that case.
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| 
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|     Normally the parameter flush is set to Z_NO_FLUSH, which allows deflate to
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|   decide how much data to accumulate before producing output, in order to
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|   maximize compression.
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| 
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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
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|   particular avail_in is zero after the call if enough output space has been
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|   provided before the call.) Flushing may degrade compression for some
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|   compression algorithms and so it should be used only when necessary.  This
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|   completes the current deflate block and follows it with an empty stored block
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|   that is three bits plus filler bits to the next byte, followed by four bytes
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|   (00 00 ff ff).
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| 
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|     If flush is set to Z_PARTIAL_FLUSH, all pending output is flushed to the
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|   output buffer, but the output is not aligned to a byte boundary.  All of the
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|   input data so far will be available to the decompressor, as for Z_SYNC_FLUSH.
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|   This completes the current deflate block and follows it with an empty fixed
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|   codes block that is 10 bits long.  This assures that enough bytes are output
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|   in order for the decompressor to finish the block before the empty fixed
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|   codes block.
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| 
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|     If flush is set to Z_BLOCK, a deflate block is completed and emitted, as
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|   for Z_SYNC_FLUSH, but the output is not aligned on a byte boundary, and up to
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|   seven bits of the current block are held to be written as the next byte after
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|   the next deflate block is completed.  In this case, the decompressor may not
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|   be provided enough bits at this point in order to complete decompression of
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|   the data provided so far to the compressor.  It may need to wait for the next
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|   block to be emitted.  This is for advanced applications that need to control
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|   the emission of deflate blocks.
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| 
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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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|   compression.
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| 
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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).  In the case of a Z_FULL_FLUSH or Z_SYNC_FLUSH, make sure that
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|   avail_out is greater than six to avoid repeated flush markers due to
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|   avail_out == 0 on return.
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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 was
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|   enough output space.  If deflate returns with Z_OK or Z_BUF_ERROR, this
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|   function must be called again with Z_FINISH and more output space (updated
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|   avail_out) but no more input data, until it returns with Z_STREAM_END or an
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|   error.  After deflate has returned Z_STREAM_END, the only possible operations
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|   on the stream are deflateReset or deflateEnd.
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| 
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|     Z_FINISH can be used in the first deflate call after deflateInit if all the
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|   compression is to be done in a single step.  In order to complete in one
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|   call, avail_out must be at least the value returned by deflateBound (see
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|   below).  Then deflate is guaranteed to return Z_STREAM_END.  If not enough
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|   output space is provided, deflate will not return Z_STREAM_END, and it must
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|   be called again as described above.
 | |
| 
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|     deflate() sets strm->adler to the Adler-32 checksum of all input read
 | |
|   so far (that is, total_in bytes).  If a gzip stream is being generated, then
 | |
|   strm->adler will be the CRC-32 checksum of the input read so far.  (See
 | |
|   deflateInit2 below.)
 | |
| 
 | |
|     deflate() may update strm->data_type if it can make a good guess about
 | |
|   the input data type (Z_BINARY or Z_TEXT).  If 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
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|   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 Z_NULL or the state was inadvertently written over
 | |
|   by the application), or Z_BUF_ERROR if no progress is possible (for example
 | |
|   avail_in or avail_out was zero).  Note that Z_BUF_ERROR is not fatal, and
 | |
|   deflate() can be called again with more input and more output space to
 | |
|   continue compressing.
 | |
| */
 | |
| 
 | |
| 
 | |
| ZEXTERN int ZEXPORT 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).
 | |
| */
 | |
| 
 | |
| 
 | |
| /*
 | |
| ZEXTERN int ZEXPORT inflateInit OF((z_streamp strm));
 | |
| 
 | |
|      Initializes the internal stream state for decompression.  The fields
 | |
|    next_in, avail_in, zalloc, zfree and opaque must be initialized before by
 | |
|    the caller.  In the current version of inflate, the provided input is not
 | |
|    read or consumed.  The allocation of a sliding window will be deferred to
 | |
|    the first call of inflate (if the decompression does not complete on the
 | |
|    first call).  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, or Z_STREAM_ERROR if the parameters are
 | |
|    invalid, such as a null pointer to the structure.  msg is set to null if
 | |
|    there is no error message.  inflateInit does not perform any decompression.
 | |
|    Actual decompression will be done by inflate().  So next_in, and avail_in,
 | |
|    next_out, and avail_out are unused and unchanged.  The current
 | |
|    implementation of inflateInit() does not process any header information --
 | |
|    that is deferred until inflate() is called.
 | |
| */
 | |
| 
 | |
| 
 | |
| ZEXTERN int ZEXPORT inflate OF((z_streamp strm, int flush));
 | |
| /*
 | |
|     inflate decompresses as much data as possible, and stops when the input
 | |
|   buffer becomes empty or the output buffer becomes full.  It may introduce
 | |
|   some output latency (reading input without producing any output) except when
 | |
|   forced to flush.
 | |
| 
 | |
|   The detailed semantics are as follows.  inflate 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), then next_in and avail_in are updated
 | |
|     accordingly, and processing will resume at this point for the next call of
 | |
|     inflate().
 | |
| 
 | |
|   - Generate 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.  If the
 | |
|   caller of inflate() does not provide both available input and available
 | |
|   output space, it is possible that there will be no progress made.  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.
 | |
| 
 | |
|     The flush parameter of inflate() can be Z_NO_FLUSH, Z_SYNC_FLUSH, Z_FINISH,
 | |
|   Z_BLOCK, or Z_TREES.  Z_SYNC_FLUSH requests that inflate() flush as much
 | |
|   output as possible to the output buffer.  Z_BLOCK requests that inflate()
 | |
|   stop if and when it gets to the next deflate block boundary.  When decoding
 | |
|   the zlib or gzip format, this will cause inflate() to return immediately
 | |
|   after the header and before the first block.  When doing a raw inflate,
 | |
|   inflate() will go ahead and process the first block, and will return when it
 | |
|   gets to the end of that block, or when it runs out of data.
 | |
| 
 | |
|     The Z_BLOCK option assists in appending to or combining deflate streams.
 | |
|   To assist in this, on return inflate() always sets strm->data_type to the
 | |
|   number of unused bits in the last byte taken from strm->next_in, plus 64 if
 | |
|   inflate() is currently decoding the last block in the deflate stream, plus
 | |
|   128 if inflate() returned immediately after decoding an end-of-block code or
 | |
|   decoding the complete header up to just before the first byte of the deflate
 | |
|   stream.  The end-of-block will not be indicated until all of the uncompressed
 | |
|   data from that block has been written to strm->next_out.  The number of
 | |
|   unused bits may in general be greater than seven, except when bit 7 of
 | |
|   data_type is set, in which case the number of unused bits will be less than
 | |
|   eight.  data_type is set as noted here every time inflate() returns for all
 | |
|   flush options, and so can be used to determine the amount of currently
 | |
|   consumed input in bits.
 | |
| 
 | |
|     The Z_TREES option behaves as Z_BLOCK does, but it also returns when the
 | |
|   end of each deflate block header is reached, before any actual data in that
 | |
|   block is decoded.  This allows the caller to determine the length of the
 | |
|   deflate block header for later use in random access within a deflate block.
 | |
|   256 is added to the value of strm->data_type when inflate() returns
 | |
|   immediately after reaching the end of the deflate block header.
 | |
| 
 | |
|     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 of the uncompressed data for the
 | |
|   operation to complete.  (The size of the uncompressed data may have been
 | |
|   saved by the compressor for this purpose.)  The use of Z_FINISH is not
 | |
|   required to perform an inflation in one step.  However it may be used to
 | |
|   inform inflate that a faster approach can be used for the single inflate()
 | |
|   call.  Z_FINISH also informs inflate to not maintain a sliding window if the
 | |
|   stream completes, which reduces inflate's memory footprint.  If the stream
 | |
|   does not complete, either because not all of the stream is provided or not
 | |
|   enough output space is provided, then a sliding window will be allocated and
 | |
|   inflate() can be called again to continue the operation as if Z_NO_FLUSH had
 | |
|   been used.
 | |
| 
 | |
|      In this implementation, inflate() always flushes as much output as
 | |
|   possible to the output buffer, and always uses the faster approach on the
 | |
|   first call.  So the effects of the flush parameter in this implementation are
 | |
|   on the return value of inflate() as noted below, when inflate() returns early
 | |
|   when Z_BLOCK or Z_TREES is used, and when inflate() avoids the allocation of
 | |
|   memory for a sliding window when Z_FINISH is used.
 | |
| 
 | |
|      If a preset dictionary is needed after this call (see inflateSetDictionary
 | |
|   below), inflate sets strm->adler to the Adler-32 checksum of the dictionary
 | |
|   chosen by the compressor and returns Z_NEED_DICT; otherwise it sets
 | |
|   strm->adler to the Adler-32 checksum of all output produced so far (that is,
 | |
|   total_out bytes) and returns Z_OK, Z_STREAM_END or an error code as described
 | |
|   below.  At the end of the stream, inflate() checks that its computed Adler-32
 | |
|   checksum is equal to that saved by the compressor and returns Z_STREAM_END
 | |
|   only if the checksum is correct.
 | |
| 
 | |
|     inflate() can decompress and check either zlib-wrapped or gzip-wrapped
 | |
|   deflate data.  The header type is detected automatically, if requested when
 | |
|   initializing with inflateInit2().  Any information contained in the gzip
 | |
|   header is not retained unless inflateGetHeader() is used.  When processing
 | |
|   gzip-wrapped deflate data, strm->adler32 is set to the CRC-32 of the output
 | |
|   produced so far.  The CRC-32 is checked against the gzip trailer, as is the
 | |
|   uncompressed length, modulo 2^32.
 | |
| 
 | |
|     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, Z_DATA_ERROR if the input data was
 | |
|   corrupted (input stream not conforming to the zlib format or incorrect check
 | |
|   value, in which case strm->msg points to a string with a more specific
 | |
|   error), Z_STREAM_ERROR if the stream structure was inconsistent (for example
 | |
|   next_in or next_out was Z_NULL, or the state was inadvertently written over
 | |
|   by the application), Z_MEM_ERROR if there was not enough memory, Z_BUF_ERROR
 | |
|   if no progress was possible or if there was not enough room in the output
 | |
|   buffer when Z_FINISH is used.  Note that Z_BUF_ERROR is not fatal, and
 | |
|   inflate() can be called again with more input and more output space to
 | |
|   continue decompressing.  If Z_DATA_ERROR is returned, the application may
 | |
|   then call inflateSync() to look for a good compression block if a partial
 | |
|   recovery of the data is to be attempted.
 | |
| */
 | |
| 
 | |
| 
 | |
| ZEXTERN int ZEXPORT 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, or Z_STREAM_ERROR if the stream state
 | |
|    was inconsistent.
 | |
| */
 | |
| 
 | |
| 
 | |
|                         /* Advanced functions */
 | |
| 
 | |
| /*
 | |
|     The following functions are needed only in some special applications.
 | |
| */
 | |
| 
 | |
| /*
 | |
| ZEXTERN int ZEXPORT 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.
 | |
| 
 | |
|      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.  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.
 | |
| 
 | |
|      For the current implementation of deflate(), a windowBits value of 8 (a
 | |
|    window size of 256 bytes) is not supported.  As a result, a request for 8
 | |
|    will result in 9 (a 512-byte window).  In that case, providing 8 to
 | |
|    inflateInit2() will result in an error when the zlib header with 9 is
 | |
|    checked against the initialization of inflate().  The remedy is to not use 8
 | |
|    with deflateInit2() with this initialization, or at least in that case use 9
 | |
|    with inflateInit2().
 | |
| 
 | |
|      windowBits can also be -8..-15 for raw deflate.  In this case, -windowBits
 | |
|    determines the window size.  deflate() will then generate raw deflate data
 | |
|    with no zlib header or trailer, and will not compute a check value.
 | |
| 
 | |
|      windowBits can also be greater than 15 for optional gzip encoding.  Add
 | |
|    16 to windowBits to write a simple gzip header and trailer around the
 | |
|    compressed data instead of a zlib wrapper.  The gzip header will have no
 | |
|    file name, no extra data, no comment, no modification time (set to zero), no
 | |
|    header crc, and the operating system will be set to the appropriate value,
 | |
|    if the operating system was determined at compile time.  If a gzip stream is
 | |
|    being written, strm->adler is a CRC-32 instead of an Adler-32.
 | |
| 
 | |
|      For raw deflate or gzip encoding, a request for a 256-byte window is
 | |
|    rejected as invalid, since only the zlib header provides a means of
 | |
|    transmitting the window size to the decompressor.
 | |
| 
 | |
|      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), Z_HUFFMAN_ONLY to force Huffman encoding only (no
 | |
|    string match), or Z_RLE to limit match distances to one (run-length
 | |
|    encoding).  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_STRATEGY and Z_HUFFMAN_ONLY.  Z_RLE is designed to be almost as
 | |
|    fast as Z_HUFFMAN_ONLY, but give better compression for PNG image data.  The
 | |
|    strategy parameter only affects the compression ratio but not the
 | |
|    correctness of the compressed output even if it is not set appropriately.
 | |
|    Z_FIXED prevents the use of dynamic Huffman codes, allowing for a simpler
 | |
|    decoder for special applications.
 | |
| 
 | |
|      deflateInit2 returns Z_OK if success, Z_MEM_ERROR if there was not enough
 | |
|    memory, Z_STREAM_ERROR if any parameter is invalid (such as an invalid
 | |
|    method), or 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.  deflateInit2 does not perform any
 | |
|    compression: this will be done by deflate().
 | |
| */
 | |
| 
 | |
| ZEXTERN int ZEXPORT deflateSetDictionary OF((z_streamp strm,
 | |
|                                              const Bytef *dictionary,
 | |
|                                              uInt  dictLength));
 | |
| /*
 | |
|      Initializes the compression dictionary from the given byte sequence
 | |
|    without producing any compressed output.  When using the zlib format, this
 | |
|    function must be called immediately after deflateInit, deflateInit2 or
 | |
|    deflateReset, and before any call of deflate.  When doing raw deflate, this
 | |
|    function must be called either before any call of deflate, or immediately
 | |
|    after the completion of a deflate block, i.e. after all input has been
 | |
|    consumed and all output has been delivered when using any of the flush
 | |
|    options Z_BLOCK, Z_PARTIAL_FLUSH, Z_SYNC_FLUSH, or Z_FULL_FLUSH.  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.
 | |
| 
 | |
|      Depending on the size of the compression data structures selected by
 | |
|    deflateInit or deflateInit2, a part of the dictionary may in effect be
 | |
|    discarded, for example if the dictionary is larger than the window size
 | |
|    provided in deflateInit or deflateInit2.  Thus the strings most likely to be
 | |
|    useful should be put at the end of the dictionary, not at the front.  In
 | |
|    addition, the current implementation of deflate will use at most the window
 | |
|    size minus 262 bytes of the provided dictionary.
 | |
| 
 | |
|      Upon return of this function, strm->adler is set to the Adler-32 value
 | |
|    of the dictionary; the decompressor may later use this value to determine
 | |
|    which dictionary has been used by the compressor.  (The Adler-32 value
 | |
|    applies to the whole dictionary even if only a subset of the dictionary is
 | |
|    actually used by the compressor.) If a raw deflate was requested, then the
 | |
|    Adler-32 value is not computed and strm->adler is not set.
 | |
| 
 | |
|      deflateSetDictionary returns Z_OK if success, or Z_STREAM_ERROR if a
 | |
|    parameter is invalid (e.g.  dictionary being Z_NULL) or the stream state is
 | |
|    inconsistent (for example if deflate has already been called for this stream
 | |
|    or if not at a block boundary for raw deflate).  deflateSetDictionary does
 | |
|    not perform any compression: this will be done by deflate().
 | |
| */
 | |
| 
 | |
| ZEXTERN int ZEXPORT deflateGetDictionary OF((z_streamp strm,
 | |
|                                              Bytef *dictionary,
 | |
|                                              uInt  *dictLength));
 | |
| /*
 | |
|      Returns the sliding dictionary being maintained by deflate.  dictLength is
 | |
|    set to the number of bytes in the dictionary, and that many bytes are copied
 | |
|    to dictionary.  dictionary must have enough space, where 32768 bytes is
 | |
|    always enough.  If deflateGetDictionary() is called with dictionary equal to
 | |
|    Z_NULL, then only the dictionary length is returned, and nothing is copied.
 | |
|    Similary, if dictLength is Z_NULL, then it is not set.
 | |
| 
 | |
|      deflateGetDictionary() may return a length less than the window size, even
 | |
|    when more than the window size in input has been provided. It may return up
 | |
|    to 258 bytes less in that case, due to how zlib's implementation of deflate
 | |
|    manages the sliding window and lookahead for matches, where matches can be
 | |
|    up to 258 bytes long. If the application needs the last window-size bytes of
 | |
|    input, then that would need to be saved by the application outside of zlib.
 | |
| 
 | |
|      deflateGetDictionary returns Z_OK on success, or Z_STREAM_ERROR if the
 | |
|    stream state is inconsistent.
 | |
| */
 | |
| 
 | |
| ZEXTERN int ZEXPORT deflateCopy OF((z_streamp dest,
 | |
|                                     z_streamp source));
 | |
| /*
 | |
|      Sets the destination stream as a complete copy of the source stream.
 | |
| 
 | |
|      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 Z_NULL).  msg is left unchanged in both source and
 | |
|    destination.
 | |
| */
 | |
| 
 | |
| ZEXTERN int ZEXPORT deflateReset OF((z_streamp strm));
 | |
| /*
 | |
|      This function is equivalent to deflateEnd followed by deflateInit, but
 | |
|    does not free and reallocate the internal compression state.  The stream
 | |
|    will leave the compression level and any other attributes that may have been
 | |
|    set unchanged.
 | |
| 
 | |
|      deflateReset returns Z_OK if success, or Z_STREAM_ERROR if the source
 | |
|    stream state was inconsistent (such as zalloc or state being Z_NULL).
 | |
| */
 | |
| 
 | |
| ZEXTERN int ZEXPORT deflateParams OF((z_streamp strm,
 | |
|                                       int level,
 | |
|                                       int strategy));
 | |
| /*
 | |
|      Dynamically update the compression level and compression strategy.  The
 | |
|    interpretation of level and strategy is as in deflateInit2().  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 approach (which is a function of the level) or the
 | |
|    strategy is changed, and if any input has been consumed in a previous
 | |
|    deflate() call, then the input available so far is compressed with the old
 | |
|    level and strategy using deflate(strm, Z_BLOCK).  There are three approaches
 | |
|    for the compression levels 0, 1..3, and 4..9 respectively.  The new level
 | |
|    and strategy will take effect at the next call of deflate().
 | |
| 
 | |
|      If a deflate(strm, Z_BLOCK) is performed by deflateParams(), and it does
 | |
|    not have enough output space to complete, then the parameter change will not
 | |
|    take effect.  In this case, deflateParams() can be called again with the
 | |
|    same parameters and more output space to try again.
 | |
| 
 | |
|      In order to assure a change in the parameters on the first try, the
 | |
|    deflate stream should be flushed using deflate() with Z_BLOCK or other flush
 | |
|    request until strm.avail_out is not zero, before calling deflateParams().
 | |
|    Then no more input data should be provided before the deflateParams() call.
 | |
|    If this is done, the old level and strategy will be applied to the data
 | |
|    compressed before deflateParams(), and the new level and strategy will be
 | |
|    applied to the the data compressed after deflateParams().
 | |
| 
 | |
|      deflateParams returns Z_OK on success, Z_STREAM_ERROR if the source stream
 | |
|    state was inconsistent or if a parameter was invalid, or Z_BUF_ERROR if
 | |
|    there was not enough output space to complete the compression of the
 | |
|    available input data before a change in the strategy or approach.  Note that
 | |
|    in the case of a Z_BUF_ERROR, the parameters are not changed.  A return
 | |
|    value of Z_BUF_ERROR is not fatal, in which case deflateParams() can be
 | |
|    retried with more output space.
 | |
| */
 | |
| 
 | |
| ZEXTERN int ZEXPORT deflateTune OF((z_streamp strm,
 | |
|                                     int good_length,
 | |
|                                     int max_lazy,
 | |
|                                     int nice_length,
 | |
|                                     int max_chain));
 | |
| /*
 | |
|      Fine tune deflate's internal compression parameters.  This should only be
 | |
|    used by someone who understands the algorithm used by zlib's deflate for
 | |
|    searching for the best matching string, and even then only by the most
 | |
|    fanatic optimizer trying to squeeze out the last compressed bit for their
 | |
|    specific input data.  Read the deflate.c source code for the meaning of the
 | |
|    max_lazy, good_length, nice_length, and max_chain parameters.
 | |
| 
 | |
|      deflateTune() can be called after deflateInit() or deflateInit2(), and
 | |
|    returns Z_OK on success, or Z_STREAM_ERROR for an invalid deflate stream.
 | |
|  */
 | |
| 
 | |
| ZEXTERN uLong ZEXPORT deflateBound OF((z_streamp strm,
 | |
|                                        uLong sourceLen));
 | |
| /*
 | |
|      deflateBound() returns an upper bound on the compressed size after
 | |
|    deflation of sourceLen bytes.  It must be called after deflateInit() or
 | |
|    deflateInit2(), and after deflateSetHeader(), if used.  This would be used
 | |
|    to allocate an output buffer for deflation in a single pass, and so would be
 | |
|    called before deflate().  If that first deflate() call is provided the
 | |
|    sourceLen input bytes, an output buffer allocated to the size returned by
 | |
|    deflateBound(), and the flush value Z_FINISH, then deflate() is guaranteed
 | |
|    to return Z_STREAM_END.  Note that it is possible for the compressed size to
 | |
|    be larger than the value returned by deflateBound() if flush options other
 | |
|    than Z_FINISH or Z_NO_FLUSH are used.
 | |
| */
 | |
| 
 | |
| ZEXTERN int ZEXPORT deflatePending OF((z_streamp strm,
 | |
|                                        unsigned *pending,
 | |
|                                        int *bits));
 | |
| /*
 | |
|      deflatePending() returns the number of bytes and bits of output that have
 | |
|    been generated, but not yet provided in the available output.  The bytes not
 | |
|    provided would be due to the available output space having being consumed.
 | |
|    The number of bits of output not provided are between 0 and 7, where they
 | |
|    await more bits to join them in order to fill out a full byte.  If pending
 | |
|    or bits are Z_NULL, then those values are not set.
 | |
| 
 | |
|      deflatePending returns Z_OK if success, or Z_STREAM_ERROR if the source
 | |
|    stream state was inconsistent.
 | |
|  */
 | |
| 
 | |
| ZEXTERN int ZEXPORT deflatePrime OF((z_streamp strm,
 | |
|                                      int bits,
 | |
|                                      int value));
 | |
| /*
 | |
|      deflatePrime() inserts bits in the deflate output stream.  The intent
 | |
|    is that this function is used to start off the deflate output with the bits
 | |
|    leftover from a previous deflate stream when appending to it.  As such, this
 | |
|    function can only be used for raw deflate, and must be used before the first
 | |
|    deflate() call after a deflateInit2() or deflateReset().  bits must be less
 | |
|    than or equal to 16, and that many of the least significant bits of value
 | |
|    will be inserted in the output.
 | |
| 
 | |
|      deflatePrime returns Z_OK if success, Z_BUF_ERROR if there was not enough
 | |
|    room in the internal buffer to insert the bits, or Z_STREAM_ERROR if the
 | |
|    source stream state was inconsistent.
 | |
| */
 | |
| 
 | |
| ZEXTERN int ZEXPORT deflateSetHeader OF((z_streamp strm,
 | |
|                                          gz_headerp head));
 | |
| /*
 | |
|      deflateSetHeader() provides gzip header information for when a gzip
 | |
|    stream is requested by deflateInit2().  deflateSetHeader() may be called
 | |
|    after deflateInit2() or deflateReset() and before the first call of
 | |
|    deflate().  The text, time, os, extra field, name, and comment information
 | |
|    in the provided gz_header structure are written to the gzip header (xflag is
 | |
|    ignored -- the extra flags are set according to the compression level).  The
 | |
|    caller must assure that, if not Z_NULL, name and comment are terminated with
 | |
|    a zero byte, and that if extra is not Z_NULL, that extra_len bytes are
 | |
|    available there.  If hcrc is true, a gzip header crc is included.  Note that
 | |
|    the current versions of the command-line version of gzip (up through version
 | |
|    1.3.x) do not support header crc's, and will report that it is a "multi-part
 | |
|    gzip file" and give up.
 | |
| 
 | |
|      If deflateSetHeader is not used, the default gzip header has text false,
 | |
|    the time set to zero, and os set to 255, with no extra, name, or comment
 | |
|    fields.  The gzip header is returned to the default state by deflateReset().
 | |
| 
 | |
|      deflateSetHeader returns Z_OK if success, or Z_STREAM_ERROR if the source
 | |
|    stream state was inconsistent.
 | |
| */
 | |
| 
 | |
| /*
 | |
| ZEXTERN int ZEXPORT inflateInit2 OF((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 zero to request that inflate use the window size in
 | |
|    the zlib header of the compressed stream.
 | |
| 
 | |
|      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 Adler-32 or a CRC-32 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
 | |
|    CRC-32 instead of an Adler-32.  Unlike the gunzip utility and gzread() (see
 | |
|    below), inflate() will not automatically decode concatenated gzip streams.
 | |
|    inflate() will return Z_STREAM_END at the end of the gzip stream.  The state
 | |
|    would need to be reset to continue decoding a subsequent gzip stream.
 | |
| 
 | |
|      inflateInit2 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, or Z_STREAM_ERROR if the parameters are
 | |
|    invalid, such as a null pointer to the structure.  msg is set to null if
 | |
|    there is no error message.  inflateInit2 does not perform any decompression
 | |
|    apart from possibly reading the zlib header if present: actual decompression
 | |
|    will be done by inflate().  (So next_in and avail_in may be modified, but
 | |
|    next_out and avail_out are unused and unchanged.) The current implementation
 | |
|    of inflateInit2() does not process any header information -- that is
 | |
|    deferred until inflate() is called.
 | |
| */
 | |
| 
 | |
| ZEXTERN int ZEXPORT inflateSetDictionary OF((z_streamp strm,
 | |
|                                              const Bytef *dictionary,
 | |
|                                              uInt  dictLength));
 | |
| /*
 | |
|      Initializes the decompression dictionary from the given uncompressed byte
 | |
|    sequence.  This function must be called immediately after a call of inflate,
 | |
|    if that call returned Z_NEED_DICT.  The dictionary chosen by the compressor
 | |
|    can be determined from the Adler-32 value returned by that call of inflate.
 | |
|    The compressor and decompressor must use exactly the same dictionary (see
 | |
|    deflateSetDictionary).  For raw inflate, this function can be called at any
 | |
|    time to set the dictionary.  If the provided dictionary is smaller than the
 | |
|    window and there is already data in the window, then the provided dictionary
 | |
|    will amend what's there.  The application must insure that the dictionary
 | |
|    that was used for compression is provided.
 | |
| 
 | |
|      inflateSetDictionary returns Z_OK if success, Z_STREAM_ERROR if a
 | |
|    parameter is invalid (e.g.  dictionary being Z_NULL) or the stream state is
 | |
|    inconsistent, Z_DATA_ERROR if the given dictionary doesn't match the
 | |
|    expected one (incorrect Adler-32 value).  inflateSetDictionary does not
 | |
|    perform any decompression: this will be done by subsequent calls of
 | |
|    inflate().
 | |
| */
 | |
| 
 | |
| ZEXTERN int ZEXPORT inflateGetDictionary OF((z_streamp strm,
 | |
|                                              Bytef *dictionary,
 | |
|                                              uInt  *dictLength));
 | |
| /*
 | |
|      Returns the sliding dictionary being maintained by inflate.  dictLength is
 | |
|    set to the number of bytes in the dictionary, and that many bytes are copied
 | |
|    to dictionary.  dictionary must have enough space, where 32768 bytes is
 | |
|    always enough.  If inflateGetDictionary() is called with dictionary equal to
 | |
|    Z_NULL, then only the dictionary length is returned, and nothing is copied.
 | |
|    Similary, if dictLength is Z_NULL, then it is not set.
 | |
| 
 | |
|      inflateGetDictionary returns Z_OK on success, or Z_STREAM_ERROR if the
 | |
|    stream state is inconsistent.
 | |
| */
 | |
| 
 | |
| ZEXTERN int ZEXPORT inflateSync OF((z_streamp strm));
 | |
| /*
 | |
|      Skips invalid compressed data until a possible full flush point (see above
 | |
|    for the description of deflate with Z_FULL_FLUSH) can be found, or until all
 | |
|    available input is skipped.  No output is provided.
 | |
| 
 | |
|      inflateSync searches for a 00 00 FF FF pattern in the compressed data.
 | |
|    All full flush points have this pattern, but not all occurrences of this
 | |
|    pattern are full flush points.
 | |
| 
 | |
|      inflateSync returns Z_OK if a possible full flush point has been found,
 | |
|    Z_BUF_ERROR if no more input was provided, Z_DATA_ERROR if no flush point
 | |
|    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.
 | |
| */
 | |
| 
 | |
| ZEXTERN int ZEXPORT inflateCopy OF((z_streamp dest,
 | |
|                                     z_streamp source));
 | |
| /*
 | |
|      Sets the destination stream as a complete copy of the source stream.
 | |
| 
 | |
|      This function can be useful when randomly accessing a large stream.  The
 | |
|    first pass through the stream can periodically record the inflate state,
 | |
|    allowing restarting inflate at those points when randomly accessing the
 | |
|    stream.
 | |
| 
 | |
|      inflateCopy 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 Z_NULL).  msg is left unchanged in both source and
 | |
|    destination.
 | |
| */
 | |
| 
 | |
| ZEXTERN int ZEXPORT inflateReset OF((z_streamp strm));
 | |
| /*
 | |
|      This function is equivalent to inflateEnd followed by inflateInit,
 | |
|    but does not free and reallocate 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 Z_NULL).
 | |
| */
 | |
| 
 | |
| ZEXTERN int ZEXPORT inflateReset2 OF((z_streamp strm,
 | |
|                                       int windowBits));
 | |
| /*
 | |
|      This function is the same as inflateReset, but it also permits changing
 | |
|    the wrap and window size requests.  The windowBits parameter is interpreted
 | |
|    the same as it is for inflateInit2.  If the window size is changed, then the
 | |
|    memory allocated for the window is freed, and the window will be reallocated
 | |
|    by inflate() if needed.
 | |
| 
 | |
|      inflateReset2 returns Z_OK if success, or Z_STREAM_ERROR if the source
 | |
|    stream state was inconsistent (such as zalloc or state being Z_NULL), or if
 | |
|    the windowBits parameter is invalid.
 | |
| */
 | |
| 
 | |
| ZEXTERN int ZEXPORT inflatePrime OF((z_streamp strm,
 | |
|                                      int bits,
 | |
|                                      int value));
 | |
| /*
 | |
|      This function inserts bits in the inflate input stream.  The intent is
 | |
|    that this function is used to start inflating at a bit position in the
 | |
|    middle of a byte.  The provided bits will be used before any bytes are used
 | |
|    from next_in.  This function should only be used with raw inflate, and
 | |
|    should be used before the first inflate() call after inflateInit2() or
 | |
|    inflateReset().  bits must be less than or equal to 16, and that many of the
 | |
|    least significant bits of value will be inserted in the input.
 | |
| 
 | |
|      If bits is negative, then the input stream bit buffer is emptied.  Then
 | |
|    inflatePrime() can be called again to put bits in the buffer.  This is used
 | |
|    to clear out bits leftover after feeding inflate a block description prior
 | |
|    to feeding inflate codes.
 | |
| 
 | |
|      inflatePrime returns Z_OK if success, or Z_STREAM_ERROR if the source
 | |
|    stream state was inconsistent.
 | |
| */
 | |
| 
 | |
| ZEXTERN long ZEXPORT inflateMark OF((z_streamp strm));
 | |
| /*
 | |
|      This function returns two values, one in the lower 16 bits of the return
 | |
|    value, and the other in the remaining upper bits, obtained by shifting the
 | |
|    return value down 16 bits.  If the upper value is -1 and the lower value is
 | |
|    zero, then inflate() is currently decoding information outside of a block.
 | |
|    If the upper value is -1 and the lower value is non-zero, then inflate is in
 | |
|    the middle of a stored block, with the lower value equaling the number of
 | |
|    bytes from the input remaining to copy.  If the upper value is not -1, then
 | |
|    it is the number of bits back from the current bit position in the input of
 | |
|    the code (literal or length/distance pair) currently being processed.  In
 | |
|    that case the lower value is the number of bytes already emitted for that
 | |
|    code.
 | |
| 
 | |
|      A code is being processed if inflate is waiting for more input to complete
 | |
|    decoding of the code, or if it has completed decoding but is waiting for
 | |
|    more output space to write the literal or match data.
 | |
| 
 | |
|      inflateMark() is used to mark locations in the input data for random
 | |
|    access, which may be at bit positions, and to note those cases where the
 | |
|    output of a code may span boundaries of random access blocks.  The current
 | |
|    location in the input stream can be determined from avail_in and data_type
 | |
|    as noted in the description for the Z_BLOCK flush parameter for inflate.
 | |
| 
 | |
|      inflateMark returns the value noted above, or -65536 if the provided
 | |
|    source stream state was inconsistent.
 | |
| */
 | |
| 
 | |
| ZEXTERN int ZEXPORT inflateGetHeader OF((z_streamp strm,
 | |
|                                          gz_headerp head));
 | |
| /*
 | |
|      inflateGetHeader() requests that gzip header information be stored in the
 | |
|    provided gz_header structure.  inflateGetHeader() may be called after
 | |
|    inflateInit2() or inflateReset(), and before the first call of inflate().
 | |
|    As inflate() processes the gzip stream, head->done is zero until the header
 | |
|    is completed, at which time head->done is set to one.  If a zlib stream is
 | |
|    being decoded, then head->done is set to -1 to indicate that there will be
 | |
|    no gzip header information forthcoming.  Note that Z_BLOCK or Z_TREES can be
 | |
|    used to force inflate() to return immediately after header processing is
 | |
|    complete and before any actual data is decompressed.
 | |
| 
 | |
|      The text, time, xflags, and os fields are filled in with the gzip header
 | |
|    contents.  hcrc is set to true if there is a header CRC.  (The header CRC
 | |
|    was valid if done is set to one.) If extra is not Z_NULL, then extra_max
 | |
|    contains the maximum number of bytes to write to extra.  Once done is true,
 | |
|    extra_len contains the actual extra field length, and extra contains the
 | |
|    extra field, or that field truncated if extra_max is less than extra_len.
 | |
|    If name is not Z_NULL, then up to name_max characters are written there,
 | |
|    terminated with a zero unless the length is greater than name_max.  If
 | |
|    comment is not Z_NULL, then up to comm_max characters are written there,
 | |
|    terminated with a zero unless the length is greater than comm_max.  When any
 | |
|    of extra, name, or comment are not Z_NULL and the respective field is not
 | |
|    present in the header, then that field is set to Z_NULL to signal its
 | |
|    absence.  This allows the use of deflateSetHeader() with the returned
 | |
|    structure to duplicate the header.  However if those fields are set to
 | |
|    allocated memory, then the application will need to save those pointers
 | |
|    elsewhere so that they can be eventually freed.
 | |
| 
 | |
|      If inflateGetHeader is not used, then the header information is simply
 | |
|    discarded.  The header is always checked for validity, including the header
 | |
|    CRC if present.  inflateReset() will reset the process to discard the header
 | |
|    information.  The application would need to call inflateGetHeader() again to
 | |
|    retrieve the header from the next gzip stream.
 | |
| 
 | |
|      inflateGetHeader returns Z_OK if success, or Z_STREAM_ERROR if the source
 | |
|    stream state was inconsistent.
 | |
| */
 | |
| 
 | |
| /*
 | |
| ZEXTERN int ZEXPORT inflateBackInit OF((z_streamp strm, int windowBits,
 | |
|                                         unsigned char FAR *window));
 | |
| 
 | |
|      Initialize the internal stream state for decompression using inflateBack()
 | |
|    calls.  The fields zalloc, zfree and opaque in strm must be initialized
 | |
|    before the call.  If zalloc and zfree are Z_NULL, then the default library-
 | |
|    derived memory allocation routines are used.  windowBits is the base two
 | |
|    logarithm of the window size, in the range 8..15.  window is a caller
 | |
|    supplied buffer of that size.  Except for special applications where it is
 | |
|    assured that deflate was used with small window sizes, windowBits must be 15
 | |
|    and a 32K byte window must be supplied to be able to decompress general
 | |
|    deflate streams.
 | |
| 
 | |
|      See inflateBack() for the usage of these routines.
 | |
| 
 | |
|      inflateBackInit will return Z_OK on success, Z_STREAM_ERROR if any of
 | |
|    the parameters are invalid, Z_MEM_ERROR if the internal state could not be
 | |
|    allocated, or Z_VERSION_ERROR if the version of the library does not match
 | |
|    the version of the header file.
 | |
| */
 | |
| 
 | |
| typedef unsigned (*in_func) OF((void FAR *,
 | |
|                                 z_const unsigned char FAR * FAR *));
 | |
| typedef int (*out_func) OF((void FAR *, unsigned char FAR *, unsigned));
 | |
| 
 | |
| ZEXTERN int ZEXPORT inflateBack OF((z_streamp strm,
 | |
|                                     in_func in, void FAR *in_desc,
 | |
|                                     out_func out, void FAR *out_desc));
 | |
| /*
 | |
|      inflateBack() does a raw inflate with a single call using a call-back
 | |
|    interface for input and output.  This is potentially more efficient than
 | |
|    inflate() for file i/o applications, in that it avoids copying between the
 | |
|    output and the sliding window by simply making the window itself the output
 | |
|    buffer.  inflate() can be faster on modern CPUs when used with large
 | |
|    buffers.  inflateBack() trusts the application to not change the output
 | |
|    buffer passed by the output function, at least until inflateBack() returns.
 | |
| 
 | |
|      inflateBackInit() must be called first to allocate the internal state
 | |
|    and to initialize the state with the user-provided window buffer.
 | |
|    inflateBack() may then be used multiple times to inflate a complete, raw
 | |
|    deflate stream with each call.  inflateBackEnd() is then called to free the
 | |
|    allocated state.
 | |
| 
 | |
|      A raw deflate stream is one with no zlib or gzip header or trailer.
 | |
|    This routine would normally be used in a utility that reads zip or gzip
 | |
|    files and writes out uncompressed files.  The utility would decode the
 | |
|    header and process the trailer on its own, hence this routine expects only
 | |
|    the raw deflate stream to decompress.  This is different from the default
 | |
|    behavior of inflate(), which expects a zlib header and trailer around the
 | |
|    deflate stream.
 | |
| 
 | |
|      inflateBack() uses two subroutines supplied by the caller that are then
 | |
|    called by inflateBack() for input and output.  inflateBack() calls those
 | |
|    routines until it reads a complete deflate stream and writes out all of the
 | |
|    uncompressed data, or until it encounters an error.  The function's
 | |
|    parameters and return types are defined above in the in_func and out_func
 | |
|    typedefs.  inflateBack() will call in(in_desc, &buf) which should return the
 | |
|    number of bytes of provided input, and a pointer to that input in buf.  If
 | |
|    there is no input available, in() must return zero -- buf is ignored in that
 | |
|    case -- and inflateBack() will return a buffer error.  inflateBack() will
 | |
|    call out(out_desc, buf, len) to write the uncompressed data buf[0..len-1].
 | |
|    out() should return zero on success, or non-zero on failure.  If out()
 | |
|    returns non-zero, inflateBack() will return with an error.  Neither in() nor
 | |
|    out() are permitted to change the contents of the window provided to
 | |
|    inflateBackInit(), which is also the buffer that out() uses to write from.
 | |
|    The length written by out() will be at most the window size.  Any non-zero
 | |
|    amount of input may be provided by in().
 | |
| 
 | |
|      For convenience, inflateBack() can be provided input on the first call by
 | |
|    setting strm->next_in and strm->avail_in.  If that input is exhausted, then
 | |
|    in() will be called.  Therefore strm->next_in must be initialized before
 | |
|    calling inflateBack().  If strm->next_in is Z_NULL, then in() will be called
 | |
|    immediately for input.  If strm->next_in is not Z_NULL, then strm->avail_in
 | |
|    must also be initialized, and then if strm->avail_in is not zero, input will
 | |
|    initially be taken from strm->next_in[0 ..  strm->avail_in - 1].
 | |
| 
 | |
|      The in_desc and out_desc parameters of inflateBack() is passed as the
 | |
|    first parameter of in() and out() respectively when they are called.  These
 | |
|    descriptors can be optionally used to pass any information that the caller-
 | |
|    supplied in() and out() functions need to do their job.
 | |
| 
 | |
|      On return, inflateBack() will set strm->next_in and strm->avail_in to
 | |
|    pass back any unused input that was provided by the last in() call.  The
 | |
|    return values of inflateBack() can be Z_STREAM_END on success, Z_BUF_ERROR
 | |
|    if in() or out() returned an error, Z_DATA_ERROR if there was a format error
 | |
|    in the deflate stream (in which case strm->msg is set to indicate the nature
 | |
|    of the error), or Z_STREAM_ERROR if the stream was not properly initialized.
 | |
|    In the case of Z_BUF_ERROR, an input or output error can be distinguished
 | |
|    using strm->next_in which will be Z_NULL only if in() returned an error.  If
 | |
|    strm->next_in is not Z_NULL, then the Z_BUF_ERROR was due to out() returning
 | |
|    non-zero.  (in() will always be called before out(), so strm->next_in is
 | |
|    assured to be defined if out() returns non-zero.)  Note that inflateBack()
 | |
|    cannot return Z_OK.
 | |
| */
 | |
| 
 | |
| ZEXTERN int ZEXPORT inflateBackEnd OF((z_streamp strm));
 | |
| /*
 | |
|      All memory allocated by inflateBackInit() is freed.
 | |
| 
 | |
|      inflateBackEnd() returns Z_OK on success, or Z_STREAM_ERROR if the stream
 | |
|    state was inconsistent.
 | |
| */
 | |
| 
 | |
| ZEXTERN uLong ZEXPORT zlibCompileFlags OF((void));
 | |
| /* Return flags indicating compile-time options.
 | |
| 
 | |
|     Type sizes, two bits each, 00 = 16 bits, 01 = 32, 10 = 64, 11 = other:
 | |
|      1.0: size of uInt
 | |
|      3.2: size of uLong
 | |
|      5.4: size of voidpf (pointer)
 | |
|      7.6: size of z_off_t
 | |
| 
 | |
|     Compiler, assembler, and debug options:
 | |
|      8: ZLIB_DEBUG
 | |
|      9: ASMV or ASMINF -- use ASM code
 | |
|      10: ZLIB_WINAPI -- exported functions use the WINAPI calling convention
 | |
|      11: 0 (reserved)
 | |
| 
 | |
|     One-time table building (smaller code, but not thread-safe if true):
 | |
|      12: BUILDFIXED -- build static block decoding tables when needed
 | |
|      13: DYNAMIC_CRC_TABLE -- build CRC calculation tables when needed
 | |
|      14,15: 0 (reserved)
 | |
| 
 | |
|     Library content (indicates missing functionality):
 | |
|      16: NO_GZCOMPRESS -- gz* functions cannot compress (to avoid linking
 | |
|                           deflate code when not needed)
 | |
|      17: NO_GZIP -- deflate can't write gzip streams, and inflate can't detect
 | |
|                     and decode gzip streams (to avoid linking crc code)
 | |
|      18-19: 0 (reserved)
 | |
| 
 | |
|     Operation variations (changes in library functionality):
 | |
|      20: PKZIP_BUG_WORKAROUND -- slightly more permissive inflate
 | |
|      21: FASTEST -- deflate algorithm with only one, lowest compression level
 | |
|      22,23: 0 (reserved)
 | |
| 
 | |
|     The sprintf variant used by gzprintf (zero is best):
 | |
|      24: 0 = vs*, 1 = s* -- 1 means limited to 20 arguments after the format
 | |
|      25: 0 = *nprintf, 1 = *printf -- 1 means gzprintf() not secure!
 | |
|      26: 0 = returns value, 1 = void -- 1 means inferred string length returned
 | |
| 
 | |
|     Remainder:
 | |
|      27-31: 0 (reserved)
 | |
|  */
 | |
| 
 | |
| #ifndef Z_SOLO
 | |
| 
 | |
|                         /* 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 and memory usage, standard memory allocation
 | |
|    functions).  The source code of these utility functions can be modified if
 | |
|    you need special options.
 | |
| */
 | |
| 
 | |
| ZEXTERN int ZEXPORT 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 the value returned by
 | |
|    compressBound(sourceLen).  Upon exit, destLen is the actual size of the
 | |
|    compressed data.  compress() is equivalent to compress2() with a level
 | |
|    parameter of Z_DEFAULT_COMPRESSION.
 | |
| 
 | |
|      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.
 | |
| */
 | |
| 
 | |
| ZEXTERN int ZEXPORT compress2 OF((Bytef *dest,   uLongf *destLen,
 | |
|                                   const Bytef *source, uLong sourceLen,
 | |
|                                   int level));
 | |
| /*
 | |
|      Compresses the source buffer into the destination buffer.  The level
 | |
|    parameter has the same meaning as in deflateInit.  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 the value returned by
 | |
|    compressBound(sourceLen).  Upon exit, destLen is the actual size of the
 | |
|    compressed data.
 | |
| 
 | |
|      compress2 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,
 | |
|    Z_STREAM_ERROR if the level parameter is invalid.
 | |
| */
 | |
| 
 | |
| ZEXTERN uLong ZEXPORT compressBound OF((uLong sourceLen));
 | |
| /*
 | |
|      compressBound() returns an upper bound on the compressed size after
 | |
|    compress() or compress2() on sourceLen bytes.  It would be used before a
 | |
|    compress() or compress2() call to allocate the destination buffer.
 | |
| */
 | |
| 
 | |
| ZEXTERN int ZEXPORT 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 uncompressed data.
 | |
| 
 | |
|      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 or incomplete.  In
 | |
|    the case where there is not enough room, uncompress() will fill the output
 | |
|    buffer with the uncompressed data up to that point.
 | |
| */
 | |
| 
 | |
| ZEXTERN int ZEXPORT uncompress2 OF((Bytef *dest,   uLongf *destLen,
 | |
|                                     const Bytef *source, uLong *sourceLen));
 | |
| /*
 | |
|      Same as uncompress, except that sourceLen is a pointer, where the
 | |
|    length of the source is *sourceLen.  On return, *sourceLen is the number of
 | |
|    source bytes consumed.
 | |
| */
 | |
| 
 | |
|                         /* gzip file access functions */
 | |
| 
 | |
| /*
 | |
|      This library supports reading and writing files in gzip (.gz) format with
 | |
|    an interface similar to that of stdio, using the functions that start with
 | |
|    "gz".  The gzip format is different from the zlib format.  gzip is a gzip
 | |
|    wrapper, documented in RFC 1952, wrapped around a deflate stream.
 | |
| */
 | |
| 
 | |
| typedef struct gzFile_s *gzFile;    /* semi-opaque gzip file descriptor */
 | |
| 
 | |
| /*
 | |
| ZEXTERN gzFile ZEXPORT 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") or
 | |
|    a strategy: 'f' for filtered data as in "wb6f", 'h' for Huffman-only
 | |
|    compression as in "wb1h", 'R' for run-length encoding as in "wb1R", or 'F'
 | |
|    for fixed code compression as in "wb9F".  (See the description of
 | |
|    deflateInit2 for more information about the strategy parameter.)  'T' will
 | |
|    request transparent writing or appending with no compression and not using
 | |
|    the gzip format.
 | |
| 
 | |
|      "a" can be used instead of "w" to request that the gzip stream that will
 | |
|    be written be appended to the file.  "+" will result in an error, since
 | |
|    reading and writing to the same gzip file is not supported.  The addition of
 | |
|    "x" when writing will create the file exclusively, which fails if the file
 | |
|    already exists.  On systems that support it, the addition of "e" when
 | |
|    reading or writing will set the flag to close the file on an execve() call.
 | |
| 
 | |
|      These functions, as well as gzip, will read and decode a sequence of gzip
 | |
|    streams in a file.  The append function of gzopen() can be used to create
 | |
|    such a file.  (Also see gzflush() for another way to do this.)  When
 | |
|    appending, gzopen does not test whether the file begins with a gzip stream,
 | |
|    nor does it look for the end of the gzip streams to begin appending.  gzopen
 | |
|    will simply append a gzip stream to the existing file.
 | |
| 
 | |
|      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.  When
 | |
|    reading, this will be detected automatically by looking for the magic two-
 | |
|    byte gzip header.
 | |
| 
 | |
|      gzopen returns NULL if the file could not be opened, if there was
 | |
|    insufficient memory to allocate the gzFile state, or if an invalid mode was
 | |
|    specified (an 'r', 'w', or 'a' was not provided, or '+' was provided).
 | |
|    errno can be checked to determine if the reason gzopen failed was that the
 | |
|    file could not be opened.
 | |
| */
 | |
| 
 | |
| ZEXTERN gzFile ZEXPORT 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 (if 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 fd = dup(fd_keep); gz = gzdopen(fd,
 | |
|    mode);.  The duplicated descriptor should be saved to avoid a leak, since
 | |
|    gzdopen does not close fd if it fails.  If you are using fileno() to get the
 | |
|    file descriptor from a FILE *, then you will have to use dup() to avoid
 | |
|    double-close()ing the file descriptor.  Both gzclose() and fclose() will
 | |
|    close the associated file descriptor, so they need to have different file
 | |
|    descriptors.
 | |
| 
 | |
|      gzdopen returns NULL if there was insufficient memory to allocate the
 | |
|    gzFile state, if an invalid mode was specified (an 'r', 'w', or 'a' was not
 | |
|    provided, or '+' was provided), or if fd is -1.  The file descriptor is not
 | |
|    used until the next gz* read, write, seek, or close operation, so gzdopen
 | |
|    will not detect if fd is invalid (unless fd is -1).
 | |
| */
 | |
| 
 | |
| ZEXTERN int ZEXPORT gzbuffer OF((gzFile file, unsigned size));
 | |
| /*
 | |
|      Set the internal buffer size used by this library's functions.  The
 | |
|    default buffer size is 8192 bytes.  This function must be called after
 | |
|    gzopen() or gzdopen(), and before any other calls that read or write the
 | |
|    file.  The buffer memory allocation is always deferred to the first read or
 | |
|    write.  Three times that size in buffer space is allocated.  A larger buffer
 | |
|    size of, for example, 64K or 128K bytes will noticeably increase the speed
 | |
|    of decompression (reading).
 | |
| 
 | |
|      The new buffer size also affects the maximum length for gzprintf().
 | |
| 
 | |
|      gzbuffer() returns 0 on success, or -1 on failure, such as being called
 | |
|    too late.
 | |
| */
 | |
| 
 | |
| ZEXTERN int ZEXPORT gzsetparams OF((gzFile file, int level, int strategy));
 | |
| /*
 | |
|      Dynamically update the compression level or strategy.  See the description
 | |
|    of deflateInit2 for the meaning of these parameters.  Previously provided
 | |
|    data is flushed before the parameter change.
 | |
| 
 | |
|      gzsetparams returns Z_OK if success, Z_STREAM_ERROR if the file was not
 | |
|    opened for writing, Z_ERRNO if there is an error writing the flushed data,
 | |
|    or Z_MEM_ERROR if there is a memory allocation error.
 | |
| */
 | |
| 
 | |
| ZEXTERN int ZEXPORT gzread OF((gzFile file, voidp buf, unsigned len));
 | |
| /*
 | |
|      Reads the given number of uncompressed bytes from the compressed file.  If
 | |
|    the input file is not in gzip format, gzread copies the given number of
 | |
|    bytes into the buffer directly from the file.
 | |
| 
 | |
|      After reaching the end of a gzip stream in the input, gzread will continue
 | |
|    to read, looking for another gzip stream.  Any number of gzip streams may be
 | |
|    concatenated in the input file, and will all be decompressed by gzread().
 | |
|    If something other than a gzip stream is encountered after a gzip stream,
 | |
|    that remaining trailing garbage is ignored (and no error is returned).
 | |
| 
 | |
|      gzread can be used to read a gzip file that is being concurrently written.
 | |
|    Upon reaching the end of the input, gzread will return with the available
 | |
|    data.  If the error code returned by gzerror is Z_OK or Z_BUF_ERROR, then
 | |
|    gzclearerr can be used to clear the end of file indicator in order to permit
 | |
|    gzread to be tried again.  Z_OK indicates that a gzip stream was completed
 | |
|    on the last gzread.  Z_BUF_ERROR indicates that the input file ended in the
 | |
|    middle of a gzip stream.  Note that gzread does not return -1 in the event
 | |
|    of an incomplete gzip stream.  This error is deferred until gzclose(), which
 | |
|    will return Z_BUF_ERROR if the last gzread ended in the middle of a gzip
 | |
|    stream.  Alternatively, gzerror can be used before gzclose to detect this
 | |
|    case.
 | |
| 
 | |
|      gzread returns the number of uncompressed bytes actually read, less than
 | |
|    len for end of file, or -1 for error.  If len is too large to fit in an int,
 | |
|    then nothing is read, -1 is returned, and the error state is set to
 | |
|    Z_STREAM_ERROR.
 | |
| */
 | |
| 
 | |
| ZEXTERN z_size_t ZEXPORT gzfread OF((voidp buf, z_size_t size, z_size_t nitems,
 | |
|                                      gzFile file));
 | |
| /*
 | |
|      Read up to nitems items of size size from file to buf, otherwise operating
 | |
|    as gzread() does.  This duplicates the interface of stdio's fread(), with
 | |
|    size_t request and return types.  If the library defines size_t, then
 | |
|    z_size_t is identical to size_t.  If not, then z_size_t is an unsigned
 | |
|    integer type that can contain a pointer.
 | |
| 
 | |
|      gzfread() returns the number of full items read of size size, or zero if
 | |
|    the end of the file was reached and a full item could not be read, or if
 | |
|    there was an error.  gzerror() must be consulted if zero is returned in
 | |
|    order to determine if there was an error.  If the multiplication of size and
 | |
|    nitems overflows, i.e. the product does not fit in a z_size_t, then nothing
 | |
|    is read, zero is returned, and the error state is set to Z_STREAM_ERROR.
 | |
| 
 | |
|      In the event that the end of file is reached and only a partial item is
 | |
|    available at the end, i.e. the remaining uncompressed data length is not a
 | |
|    multiple of size, then the final partial item is nevetheless read into buf
 | |
|    and the end-of-file flag is set.  The length of the partial item read is not
 | |
|    provided, but could be inferred from the result of gztell().  This behavior
 | |
|    is the same as the behavior of fread() implementations in common libraries,
 | |
|    but it prevents the direct use of gzfread() to read a concurrently written
 | |
|    file, reseting and retrying on end-of-file, when size is not 1.
 | |
| */
 | |
| 
 | |
| ZEXTERN int ZEXPORT gzwrite OF((gzFile file,
 | |
|                                 voidpc buf, unsigned len));
 | |
| /*
 | |
|      Writes the given number of uncompressed bytes into the compressed file.
 | |
|    gzwrite returns the number of uncompressed bytes written or 0 in case of
 | |
|    error.
 | |
| */
 | |
| 
 | |
| ZEXTERN z_size_t ZEXPORT gzfwrite OF((voidpc buf, z_size_t size,
 | |
|                                       z_size_t nitems, gzFile file));
 | |
| /*
 | |
|      gzfwrite() writes nitems items of size size from buf to file, duplicating
 | |
|    the interface of stdio's fwrite(), with size_t request and return types.  If
 | |
|    the library defines size_t, then z_size_t is identical to size_t.  If not,
 | |
|    then z_size_t is an unsigned integer type that can contain a pointer.
 | |
| 
 | |
|      gzfwrite() returns the number of full items written of size size, or zero
 | |
|    if there was an error.  If the multiplication of size and nitems overflows,
 | |
|    i.e. the product does not fit in a z_size_t, then nothing is written, zero
 | |
|    is returned, and the error state is set to Z_STREAM_ERROR.
 | |
| */
 | |
| 
 | |
| ZEXTERN int ZEXPORTVA gzprintf Z_ARG((gzFile file, const char *format, ...));
 | |
| /*
 | |
|      Converts, formats, and writes the arguments to the compressed file under
 | |
|    control of the format string, as in fprintf.  gzprintf returns the number of
 | |
|    uncompressed bytes actually written, or a negative zlib error code in case
 | |
|    of error.  The number of uncompressed bytes written is limited to 8191, or
 | |
|    one less than the buffer size given to gzbuffer().  The caller should assure
 | |
|    that this limit is not exceeded.  If it is exceeded, then gzprintf() will
 | |
|    return an error (0) with nothing written.  In this case, there may also be a
 | |
|    buffer overflow with unpredictable consequences, which is possible only if
 | |
|    zlib was compiled with the insecure functions sprintf() or vsprintf()
 | |
|    because the secure snprintf() or vsnprintf() functions were not available.
 | |
|    This can be determined using zlibCompileFlags().
 | |
| */
 | |
| 
 | |
| ZEXTERN int ZEXPORT gzputs OF((gzFile file, const char *s));
 | |
| /*
 | |
|      Writes the given null-terminated string to the compressed file, excluding
 | |
|    the terminating null character.
 | |
| 
 | |
|      gzputs returns the number of characters written, or -1 in case of error.
 | |
| */
 | |
| 
 | |
| ZEXTERN char * ZEXPORT gzgets OF((gzFile file, char *buf, int len));
 | |
| /*
 | |
|      Reads bytes from the compressed file until len-1 characters are read, or a
 | |
|    newline character is read and transferred to buf, or an end-of-file
 | |
|    condition is encountered.  If any characters are read or if len == 1, the
 | |
|    string is terminated with a null character.  If no characters are read due
 | |
|    to an end-of-file or len < 1, then the buffer is left untouched.
 | |
| 
 | |
|      gzgets returns buf which is a null-terminated string, or it returns NULL
 | |
|    for end-of-file or in case of error.  If there was an error, the contents at
 | |
|    buf are indeterminate.
 | |
| */
 | |
| 
 | |
| ZEXTERN int ZEXPORT gzputc OF((gzFile file, int c));
 | |
| /*
 | |
|      Writes c, converted to an unsigned char, into the compressed file.  gzputc
 | |
|    returns the value that was written, or -1 in case of error.
 | |
| */
 | |
| 
 | |
| ZEXTERN int ZEXPORT gzgetc OF((gzFile file));
 | |
| /*
 | |
|      Reads one byte from the compressed file.  gzgetc returns this byte or -1
 | |
|    in case of end of file or error.  This is implemented as a macro for speed.
 | |
|    As such, it does not do all of the checking the other functions do.  I.e.
 | |
|    it does not check to see if file is NULL, nor whether the structure file
 | |
|    points to has been clobbered or not.
 | |
| */
 | |
| 
 | |
| ZEXTERN int ZEXPORT gzungetc OF((int c, gzFile file));
 | |
| /*
 | |
|      Push one character back onto the stream to be read as the first character
 | |
|    on the next read.  At least one character of push-back is allowed.
 | |
|    gzungetc() returns the character pushed, or -1 on failure.  gzungetc() will
 | |
|    fail if c is -1, and may fail if a character has been pushed but not read
 | |
|    yet.  If gzungetc is used immediately after gzopen or gzdopen, at least the
 | |
|    output buffer size of pushed characters is allowed.  (See gzbuffer above.)
 | |
|    The pushed character will be discarded if the stream is repositioned with
 | |
|    gzseek() or gzrewind().
 | |
| */
 | |
| 
 | |
| ZEXTERN int ZEXPORT 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 is only permitted when writing.
 | |
| 
 | |
|      If the flush parameter is Z_FINISH, the remaining data is written and the
 | |
|    gzip stream is completed in the output.  If gzwrite() is called again, a new
 | |
|    gzip stream will be started in the output.  gzread() is able to read such
 | |
|    concatenated gzip streams.
 | |
| 
 | |
|      gzflush should be called only when strictly necessary because it will
 | |
|    degrade compression if called too often.
 | |
| */
 | |
| 
 | |
| /*
 | |
| ZEXTERN z_off_t ZEXPORT gzseek OF((gzFile file,
 | |
|                                    z_off_t offset, int whence));
 | |
| 
 | |
|      Sets the starting position for the next gzread or gzwrite on the given
 | |
|    compressed file.  The offset represents a number of bytes in the
 | |
|    uncompressed data stream.  The whence parameter is defined as in lseek(2);
 | |
|    the value SEEK_END is not supported.
 | |
| 
 | |
|      If the file is opened for reading, this function is emulated but can be
 | |
|    extremely slow.  If the file is opened for writing, only forward seeks are
 | |
|    supported; gzseek then compresses a sequence of zeroes up to the new
 | |
|    starting position.
 | |
| 
 | |
|      gzseek returns the resulting offset location as measured in bytes from
 | |
|    the beginning of the uncompressed stream, or -1 in case of error, in
 | |
|    particular if the file is opened for writing and the new starting position
 | |
|    would be before the current position.
 | |
| */
 | |
| 
 | |
| ZEXTERN int ZEXPORT    gzrewind OF((gzFile file));
 | |
| /*
 | |
|      Rewinds the given file. This function is supported only for reading.
 | |
| 
 | |
|      gzrewind(file) is equivalent to (int)gzseek(file, 0L, SEEK_SET)
 | |
| */
 | |
| 
 | |
| /*
 | |
| ZEXTERN z_off_t ZEXPORT    gztell OF((gzFile file));
 | |
| 
 | |
|      Returns the starting position for the next gzread or gzwrite on the given
 | |
|    compressed file.  This position represents a number of bytes in the
 | |
|    uncompressed data stream, and is zero when starting, even if appending or
 | |
|    reading a gzip stream from the middle of a file using gzdopen().
 | |
| 
 | |
|      gztell(file) is equivalent to gzseek(file, 0L, SEEK_CUR)
 | |
| */
 | |
| 
 | |
| /*
 | |
| ZEXTERN z_off_t ZEXPORT gzoffset OF((gzFile file));
 | |
| 
 | |
|      Returns the current offset in the file being read or written.  This offset
 | |
|    includes the count of bytes that precede the gzip stream, for example when
 | |
|    appending or when using gzdopen() for reading.  When reading, the offset
 | |
|    does not include as yet unused buffered input.  This information can be used
 | |
|    for a progress indicator.  On error, gzoffset() returns -1.
 | |
| */
 | |
| 
 | |
| ZEXTERN int ZEXPORT gzeof OF((gzFile file));
 | |
| /*
 | |
|      Returns true (1) if the end-of-file indicator has been set while reading,
 | |
|    false (0) otherwise.  Note that the end-of-file indicator is set only if the
 | |
|    read tried to go past the end of the input, but came up short.  Therefore,
 | |
|    just like feof(), gzeof() may return false even if there is no more data to
 | |
|    read, in the event that the last read request was for the exact number of
 | |
|    bytes remaining in the input file.  This will happen if the input file size
 | |
|    is an exact multiple of the buffer size.
 | |
| 
 | |
|      If gzeof() returns true, then the read functions will return no more data,
 | |
|    unless the end-of-file indicator is reset by gzclearerr() and the input file
 | |
|    has grown since the previous end of file was detected.
 | |
| */
 | |
| 
 | |
| ZEXTERN int ZEXPORT gzdirect OF((gzFile file));
 | |
| /*
 | |
|      Returns true (1) if file is being copied directly while reading, or false
 | |
|    (0) if file is a gzip stream being decompressed.
 | |
| 
 | |
|      If the input file is empty, gzdirect() will return true, since the input
 | |
|    does not contain a gzip stream.
 | |
| 
 | |
|      If gzdirect() is used immediately after gzopen() or gzdopen() it will
 | |
|    cause buffers to be allocated to allow reading the file to determine if it
 | |
|    is a gzip file.  Therefore if gzbuffer() is used, it should be called before
 | |
|    gzdirect().
 | |
| 
 | |
|      When writing, gzdirect() returns true (1) if transparent writing was
 | |
|    requested ("wT" for the gzopen() mode), or false (0) otherwise.  (Note:
 | |
|    gzdirect() is not needed when writing.  Transparent writing must be
 | |
|    explicitly requested, so the application already knows the answer.  When
 | |
|    linking statically, using gzdirect() will include all of the zlib code for
 | |
|    gzip file reading and decompression, which may not be desired.)
 | |
| */
 | |
| 
 | |
| ZEXTERN int ZEXPORT    gzclose OF((gzFile file));
 | |
| /*
 | |
|      Flushes all pending output if necessary, closes the compressed file and
 | |
|    deallocates the (de)compression state.  Note that once file is closed, you
 | |
|    cannot call gzerror with file, since its structures have been deallocated.
 | |
|    gzclose must not be called more than once on the same file, just as free
 | |
|    must not be called more than once on the same allocation.
 | |
| 
 | |
|      gzclose will return Z_STREAM_ERROR if file is not valid, Z_ERRNO on a
 | |
|    file operation error, Z_MEM_ERROR if out of memory, Z_BUF_ERROR if the
 | |
|    last read ended in the middle of a gzip stream, or Z_OK on success.
 | |
| */
 | |
| 
 | |
| ZEXTERN int ZEXPORT gzclose_r OF((gzFile file));
 | |
| ZEXTERN int ZEXPORT gzclose_w OF((gzFile file));
 | |
| /*
 | |
|      Same as gzclose(), but gzclose_r() is only for use when reading, and
 | |
|    gzclose_w() is only for use when writing or appending.  The advantage to
 | |
|    using these instead of gzclose() is that they avoid linking in zlib
 | |
|    compression or decompression code that is not used when only reading or only
 | |
|    writing respectively.  If gzclose() is used, then both compression and
 | |
|    decompression code will be included the application when linking to a static
 | |
|    zlib library.
 | |
| */
 | |
| 
 | |
| ZEXTERN const char * ZEXPORT 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.
 | |
| 
 | |
|      The application must not modify the returned string.  Future calls to
 | |
|    this function may invalidate the previously returned string.  If file is
 | |
|    closed, then the string previously returned by gzerror will no longer be
 | |
|    available.
 | |
| 
 | |
|      gzerror() should be used to distinguish errors from end-of-file for those
 | |
|    functions above that do not distinguish those cases in their return values.
 | |
| */
 | |
| 
 | |
| ZEXTERN void ZEXPORT gzclearerr OF((gzFile file));
 | |
| /*
 | |
|      Clears the error and end-of-file flags for file.  This is analogous to the
 | |
|    clearerr() function in stdio.  This is useful for continuing to read a gzip
 | |
|    file that is being written concurrently.
 | |
| */
 | |
| 
 | |
| #endif /* !Z_SOLO */
 | |
| 
 | |
|                         /* checksum functions */
 | |
| 
 | |
| /*
 | |
|      These functions are not related to compression but are exported
 | |
|    anyway because they might be useful in applications using the compression
 | |
|    library.
 | |
| */
 | |
| 
 | |
| ZEXTERN uLong ZEXPORT 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 Z_NULL, this function returns the
 | |
|    required initial value for the checksum.
 | |
| 
 | |
|      An Adler-32 checksum is almost as reliable as a CRC-32 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();
 | |
| */
 | |
| 
 | |
| ZEXTERN uLong ZEXPORT adler32_z OF((uLong adler, const Bytef *buf,
 | |
|                                     z_size_t len));
 | |
| /*
 | |
|      Same as adler32(), but with a size_t length.
 | |
| */
 | |
| 
 | |
| /*
 | |
| ZEXTERN uLong ZEXPORT adler32_combine OF((uLong adler1, uLong adler2,
 | |
|                                           z_off_t len2));
 | |
| 
 | |
|      Combine two Adler-32 checksums into one.  For two sequences of bytes, seq1
 | |
|    and seq2 with lengths len1 and len2, Adler-32 checksums were calculated for
 | |
|    each, adler1 and adler2.  adler32_combine() returns the Adler-32 checksum of
 | |
|    seq1 and seq2 concatenated, requiring only adler1, adler2, and len2.  Note
 | |
|    that the z_off_t type (like off_t) is a signed integer.  If len2 is
 | |
|    negative, the result has no meaning or utility.
 | |
| */
 | |
| 
 | |
| ZEXTERN uLong ZEXPORT crc32   OF((uLong crc, const Bytef *buf, uInt len));
 | |
| /*
 | |
|      Update a running CRC-32 with the bytes buf[0..len-1] and return the
 | |
|    updated CRC-32.  If buf is Z_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();
 | |
| */
 | |
| 
 | |
| ZEXTERN uLong ZEXPORT crc32_z OF((uLong adler, const Bytef *buf,
 | |
|                                   z_size_t len));
 | |
| /*
 | |
|      Same as crc32(), but with a size_t length.
 | |
| */
 | |
| 
 | |
| /*
 | |
| ZEXTERN uLong ZEXPORT crc32_combine OF((uLong crc1, uLong crc2, z_off_t len2));
 | |
| 
 | |
|      Combine two CRC-32 check values into one.  For two sequences of bytes,
 | |
|    seq1 and seq2 with lengths len1 and len2, CRC-32 check values were
 | |
|    calculated for each, crc1 and crc2.  crc32_combine() returns the CRC-32
 | |
|    check value of seq1 and seq2 concatenated, requiring only crc1, crc2, and
 | |
|    len2.
 | |
| */
 | |
| 
 | |
| 
 | |
|                         /* various hacks, don't look :) */
 | |
| 
 | |
| /* deflateInit and inflateInit are macros to allow checking the zlib version
 | |
|  * and the compiler's view of z_stream:
 | |
|  */
 | |
| ZEXTERN int ZEXPORT deflateInit_ OF((z_streamp strm, int level,
 | |
|                                      const char *version, int stream_size));
 | |
| ZEXTERN int ZEXPORT inflateInit_ OF((z_streamp strm,
 | |
|                                      const char *version, int stream_size));
 | |
| ZEXTERN int ZEXPORT deflateInit2_ OF((z_streamp strm, int  level, int  method,
 | |
|                                       int windowBits, int memLevel,
 | |
|                                       int strategy, const char *version,
 | |
|                                       int stream_size));
 | |
| ZEXTERN int ZEXPORT inflateInit2_ OF((z_streamp strm, int  windowBits,
 | |
|                                       const char *version, int stream_size));
 | |
| ZEXTERN int ZEXPORT inflateBackInit_ OF((z_streamp strm, int windowBits,
 | |
|                                          unsigned char FAR *window,
 | |
|                                          const char *version,
 | |
|                                          int stream_size));
 | |
| #ifdef Z_PREFIX_SET
 | |
| #  define z_deflateInit(strm, level) \
 | |
|           deflateInit_((strm), (level), ZLIB_VERSION, (int)sizeof(z_stream))
 | |
| #  define z_inflateInit(strm) \
 | |
|           inflateInit_((strm), ZLIB_VERSION, (int)sizeof(z_stream))
 | |
| #  define z_deflateInit2(strm, level, method, windowBits, memLevel, strategy) \
 | |
|           deflateInit2_((strm),(level),(method),(windowBits),(memLevel),\
 | |
|                         (strategy), ZLIB_VERSION, (int)sizeof(z_stream))
 | |
| #  define z_inflateInit2(strm, windowBits) \
 | |
|           inflateInit2_((strm), (windowBits), ZLIB_VERSION, \
 | |
|                         (int)sizeof(z_stream))
 | |
| #  define z_inflateBackInit(strm, windowBits, window) \
 | |
|           inflateBackInit_((strm), (windowBits), (window), \
 | |
|                            ZLIB_VERSION, (int)sizeof(z_stream))
 | |
| #else
 | |
| #  define deflateInit(strm, level) \
 | |
|           deflateInit_((strm), (level), ZLIB_VERSION, (int)sizeof(z_stream))
 | |
| #  define inflateInit(strm) \
 | |
|           inflateInit_((strm), ZLIB_VERSION, (int)sizeof(z_stream))
 | |
| #  define deflateInit2(strm, level, method, windowBits, memLevel, strategy) \
 | |
|           deflateInit2_((strm),(level),(method),(windowBits),(memLevel),\
 | |
|                         (strategy), ZLIB_VERSION, (int)sizeof(z_stream))
 | |
| #  define inflateInit2(strm, windowBits) \
 | |
|           inflateInit2_((strm), (windowBits), ZLIB_VERSION, \
 | |
|                         (int)sizeof(z_stream))
 | |
| #  define inflateBackInit(strm, windowBits, window) \
 | |
|           inflateBackInit_((strm), (windowBits), (window), \
 | |
|                            ZLIB_VERSION, (int)sizeof(z_stream))
 | |
| #endif
 | |
| 
 | |
| #ifndef Z_SOLO
 | |
| 
 | |
| /* gzgetc() macro and its supporting function and exposed data structure.  Note
 | |
|  * that the real internal state is much larger than the exposed structure.
 | |
|  * This abbreviated structure exposes just enough for the gzgetc() macro.  The
 | |
|  * user should not mess with these exposed elements, since their names or
 | |
|  * behavior could change in the future, perhaps even capriciously.  They can
 | |
|  * only be used by the gzgetc() macro.  You have been warned.
 | |
|  */
 | |
| struct gzFile_s {
 | |
|     unsigned have;
 | |
|     unsigned char *next;
 | |
|     z_off64_t pos;
 | |
| };
 | |
| ZEXTERN int ZEXPORT gzgetc_ OF((gzFile file));  /* backward compatibility */
 | |
| #ifdef Z_PREFIX_SET
 | |
| #  undef z_gzgetc
 | |
| #  define z_gzgetc(g) \
 | |
|           ((g)->have ? ((g)->have--, (g)->pos++, *((g)->next)++) : (gzgetc)(g))
 | |
| #else
 | |
| #  define gzgetc(g) \
 | |
|           ((g)->have ? ((g)->have--, (g)->pos++, *((g)->next)++) : (gzgetc)(g))
 | |
| #endif
 | |
| 
 | |
| /* provide 64-bit offset functions if _LARGEFILE64_SOURCE defined, and/or
 | |
|  * change the regular functions to 64 bits if _FILE_OFFSET_BITS is 64 (if
 | |
|  * both are true, the application gets the *64 functions, and the regular
 | |
|  * functions are changed to 64 bits) -- in case these are set on systems
 | |
|  * without large file support, _LFS64_LARGEFILE must also be true
 | |
|  */
 | |
| #ifdef Z_LARGE64
 | |
|    ZEXTERN gzFile ZEXPORT gzopen64 OF((const char *, const char *));
 | |
|    ZEXTERN z_off64_t ZEXPORT gzseek64 OF((gzFile, z_off64_t, int));
 | |
|    ZEXTERN z_off64_t ZEXPORT gztell64 OF((gzFile));
 | |
|    ZEXTERN z_off64_t ZEXPORT gzoffset64 OF((gzFile));
 | |
|    ZEXTERN uLong ZEXPORT adler32_combine64 OF((uLong, uLong, z_off64_t));
 | |
|    ZEXTERN uLong ZEXPORT crc32_combine64 OF((uLong, uLong, z_off64_t));
 | |
| #endif
 | |
| 
 | |
| #if !defined(ZLIB_INTERNAL) && defined(Z_WANT64)
 | |
| #  ifdef Z_PREFIX_SET
 | |
| #    define z_gzopen z_gzopen64
 | |
| #    define z_gzseek z_gzseek64
 | |
| #    define z_gztell z_gztell64
 | |
| #    define z_gzoffset z_gzoffset64
 | |
| #    define z_adler32_combine z_adler32_combine64
 | |
| #    define z_crc32_combine z_crc32_combine64
 | |
| #  else
 | |
| #    define gzopen gzopen64
 | |
| #    define gzseek gzseek64
 | |
| #    define gztell gztell64
 | |
| #    define gzoffset gzoffset64
 | |
| #    define adler32_combine adler32_combine64
 | |
| #    define crc32_combine crc32_combine64
 | |
| #  endif
 | |
| #  ifndef Z_LARGE64
 | |
|      ZEXTERN gzFile ZEXPORT gzopen64 OF((const char *, const char *));
 | |
|      ZEXTERN z_off_t ZEXPORT gzseek64 OF((gzFile, z_off_t, int));
 | |
|      ZEXTERN z_off_t ZEXPORT gztell64 OF((gzFile));
 | |
|      ZEXTERN z_off_t ZEXPORT gzoffset64 OF((gzFile));
 | |
|      ZEXTERN uLong ZEXPORT adler32_combine64 OF((uLong, uLong, z_off_t));
 | |
|      ZEXTERN uLong ZEXPORT crc32_combine64 OF((uLong, uLong, z_off_t));
 | |
| #  endif
 | |
| #else
 | |
|    ZEXTERN gzFile ZEXPORT gzopen OF((const char *, const char *));
 | |
|    ZEXTERN z_off_t ZEXPORT gzseek OF((gzFile, z_off_t, int));
 | |
|    ZEXTERN z_off_t ZEXPORT gztell OF((gzFile));
 | |
|    ZEXTERN z_off_t ZEXPORT gzoffset OF((gzFile));
 | |
|    ZEXTERN uLong ZEXPORT adler32_combine OF((uLong, uLong, z_off_t));
 | |
|    ZEXTERN uLong ZEXPORT crc32_combine OF((uLong, uLong, z_off_t));
 | |
| #endif
 | |
| 
 | |
| #else /* Z_SOLO */
 | |
| 
 | |
|    ZEXTERN uLong ZEXPORT adler32_combine OF((uLong, uLong, z_off_t));
 | |
|    ZEXTERN uLong ZEXPORT crc32_combine OF((uLong, uLong, z_off_t));
 | |
| 
 | |
| #endif /* !Z_SOLO */
 | |
| 
 | |
| /* undocumented functions */
 | |
| ZEXTERN const char   * ZEXPORT zError           OF((int));
 | |
| ZEXTERN int            ZEXPORT inflateSyncPoint OF((z_streamp));
 | |
| ZEXTERN const z_crc_t FAR * ZEXPORT get_crc_table    OF((void));
 | |
| ZEXTERN int            ZEXPORT inflateUndermine OF((z_streamp, int));
 | |
| ZEXTERN int            ZEXPORT inflateValidate OF((z_streamp, int));
 | |
| ZEXTERN unsigned long  ZEXPORT inflateCodesUsed OF ((z_streamp));
 | |
| ZEXTERN int            ZEXPORT inflateResetKeep OF((z_streamp));
 | |
| ZEXTERN int            ZEXPORT deflateResetKeep OF((z_streamp));
 | |
| #if (defined(_WIN32) || defined(__CYGWIN__)) && !defined(Z_SOLO)
 | |
| ZEXTERN gzFile         ZEXPORT gzopen_w OF((const wchar_t *path,
 | |
|                                             const char *mode));
 | |
| #endif
 | |
| #if defined(STDC) || defined(Z_HAVE_STDARG_H)
 | |
| #  ifndef Z_SOLO
 | |
| ZEXTERN int            ZEXPORTVA gzvprintf Z_ARG((gzFile file,
 | |
|                                                   const char *format,
 | |
|                                                   va_list va));
 | |
| #  endif
 | |
| #endif
 | |
| 
 | |
| #ifdef __cplusplus
 | |
| }
 | |
| #endif
 | |
| 
 | |
| #endif /* ZLIB_H */
 | 
