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![Yinghai Lu](/assets/img/avatar_default.png)
Now with 64bit bzImage and kexec tools, we support ramdisk that size is bigger than 2g, as we could put it above 4G. Found compressed initramfs image could not be decompressed properly. It turns out that image length is int during decompress detection, and it will become < 0 when length is more than 2G. Furthermore, during decompressing len as int is used for inbuf count, that has problem too. Change len to long, that should be ok as on 32 bit platform long is 32bits. Tested with following compressed initramfs image as root with kexec. gzip, bzip2, xz, lzma, lzop, lz4. run time for populate_rootfs(): size name Nehalem-EX Westmere-EX Ivybridge-EX 9034400256 root_img : 26s 24s 30s 3561095057 root_img.lz4 : 28s 27s 27s 3459554629 root_img.lzo : 29s 29s 28s 3219399480 root_img.gz : 64s 62s 49s 2251594592 root_img.xz : 262s 260s 183s 2226366598 root_img.lzma: 386s 376s 277s 2901482513 root_img.bz2 : 635s 599s Signed-off-by: Yinghai Lu <yinghai@kernel.org> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Rashika Kheria <rashika.kheria@gmail.com> Cc: Josh Triplett <josh@joshtriplett.org> Cc: Kyungsik Lee <kyungsik.lee@lge.com> Cc: P J P <ppandit@redhat.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp> Cc: "Daniel M. Weeks" <dan@danweeks.net> Cc: Alexandre Courbot <acourbot@nvidia.com> Cc: Jan Beulich <JBeulich@suse.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
593 lines
28 KiB
C
593 lines
28 KiB
C
/* zlib.h -- interface of the 'zlib' general purpose compression library
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Copyright (C) 1995-2005 Jean-loup Gailly and Mark Adler
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This software is provided 'as-is', without any express or implied
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warranty. In no event will the authors be held liable for any damages
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arising from the use of this software.
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Permission is granted to anyone to use this software for any purpose,
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including commercial applications, and to alter it and redistribute it
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freely, subject to the following restrictions:
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1. The origin of this software must not be misrepresented; you must not
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claim that you wrote the original software. If you use this software
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in a product, an acknowledgment in the product documentation would be
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appreciated but is not required.
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2. Altered source versions must be plainly marked as such, and must not be
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misrepresented as being the original software.
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3. This notice may not be removed or altered from any source distribution.
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Jean-loup Gailly Mark Adler
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jloup@gzip.org madler@alumni.caltech.edu
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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://www.ietf.org/rfc/rfc1950.txt
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(zlib format), rfc1951.txt (deflate format) and rfc1952.txt (gzip format).
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*/
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#ifndef _ZLIB_H
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#define _ZLIB_H
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#include <linux/zconf.h>
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/* zlib deflate based on ZLIB_VERSION "1.1.3" */
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/* zlib inflate based on ZLIB_VERSION "1.2.3" */
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/*
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This is a modified version of zlib for use inside the Linux kernel.
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The main changes are to perform all memory allocation in advance.
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Inflation Changes:
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* Z_PACKET_FLUSH is added and used by ppp_deflate. Before returning
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this checks there is no more input data available and the next data
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is a STORED block. It also resets the mode to be read for the next
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data, all as per PPP requirements.
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* Addition of zlib_inflateIncomp which copies incompressible data into
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the history window and adjusts the accoutning without calling
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zlib_inflate itself to inflate the data.
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*/
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/*
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The 'zlib' compression library provides in-memory compression and
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decompression functions, including integrity checks of the uncompressed
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data. This version of the library supports only one compression method
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(deflation) but other algorithms will be added later and will have the same
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stream interface.
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Compression can be done in a single step if the buffers are large
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enough (for example if an input file is mmap'ed), or can be done by
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repeated calls of the compression function. In the latter case, the
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application must provide more input and/or consume the output
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(providing more output space) before each call.
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The compressed data format used by default by the in-memory functions is
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the zlib format, which is a zlib wrapper documented in RFC 1950, wrapped
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around a deflate stream, which is itself documented in RFC 1951.
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The library also supports reading and writing files in gzip (.gz) format
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with an interface similar to that of stdio.
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The zlib format was designed to be compact and fast for use in memory
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and on communications channels. The gzip format was designed for single-
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file compression on file systems, has a larger header than zlib to maintain
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directory information, and uses a different, slower check method than zlib.
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The library does not install any signal handler. The decoder checks
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the consistency of the compressed data, so the library should never
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crash even in case of corrupted input.
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*/
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struct internal_state;
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typedef struct z_stream_s {
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const Byte *next_in; /* next input byte */
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uLong avail_in; /* number of bytes available at next_in */
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uLong total_in; /* total nb of input bytes read so far */
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Byte *next_out; /* next output byte should be put there */
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uLong avail_out; /* remaining free space at next_out */
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uLong total_out; /* total nb of bytes output so far */
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char *msg; /* last error message, NULL if no error */
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struct internal_state *state; /* not visible by applications */
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void *workspace; /* memory allocated for this stream */
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int data_type; /* best guess about the data type: ascii or binary */
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uLong adler; /* adler32 value of the uncompressed data */
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uLong reserved; /* reserved for future use */
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} z_stream;
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typedef z_stream *z_streamp;
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/*
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The application must update next_in and avail_in when avail_in has
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dropped to zero. It must update next_out and avail_out when avail_out
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has dropped to zero. The application must initialize zalloc, zfree and
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opaque before calling the init function. All other fields are set by the
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compression library and must not be updated by the application.
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The opaque value provided by the application will be passed as the first
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parameter for calls of zalloc and zfree. This can be useful for custom
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memory management. The compression library attaches no meaning to the
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opaque value.
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zalloc must return NULL if there is not enough memory for the object.
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If zlib is used in a multi-threaded application, zalloc and zfree must be
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thread safe.
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On 16-bit systems, the functions zalloc and zfree must be able to allocate
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exactly 65536 bytes, but will not be required to allocate more than this
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if the symbol MAXSEG_64K is defined (see zconf.h). WARNING: On MSDOS,
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pointers returned by zalloc for objects of exactly 65536 bytes *must*
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have their offset normalized to zero. The default allocation function
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provided by this library ensures this (see zutil.c). To reduce memory
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requirements and avoid any allocation of 64K objects, at the expense of
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compression ratio, compile the library with -DMAX_WBITS=14 (see zconf.h).
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The fields total_in and total_out can be used for statistics or
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progress reports. After compression, total_in holds the total size of
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the uncompressed data and may be saved for use in the decompressor
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(particularly if the decompressor wants to decompress everything in
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a single step).
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*/
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/* constants */
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#define Z_NO_FLUSH 0
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#define Z_PARTIAL_FLUSH 1 /* will be removed, use Z_SYNC_FLUSH instead */
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#define Z_PACKET_FLUSH 2
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#define Z_SYNC_FLUSH 3
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#define Z_FULL_FLUSH 4
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#define Z_FINISH 5
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#define Z_BLOCK 6 /* Only for inflate at present */
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/* Allowed flush values; see deflate() and inflate() below for details */
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#define Z_OK 0
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#define Z_STREAM_END 1
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#define Z_NEED_DICT 2
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#define Z_ERRNO (-1)
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#define Z_STREAM_ERROR (-2)
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#define Z_DATA_ERROR (-3)
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#define Z_MEM_ERROR (-4)
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#define Z_BUF_ERROR (-5)
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#define Z_VERSION_ERROR (-6)
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/* Return codes for the compression/decompression functions. Negative
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* values are errors, positive values are used for special but normal events.
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*/
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#define Z_NO_COMPRESSION 0
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#define Z_BEST_SPEED 1
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#define Z_BEST_COMPRESSION 9
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#define Z_DEFAULT_COMPRESSION (-1)
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/* compression levels */
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#define Z_FILTERED 1
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#define Z_HUFFMAN_ONLY 2
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#define Z_DEFAULT_STRATEGY 0
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/* compression strategy; see deflateInit2() below for details */
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#define Z_BINARY 0
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#define Z_ASCII 1
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#define Z_UNKNOWN 2
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/* Possible values of the data_type field */
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#define Z_DEFLATED 8
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/* The deflate compression method (the only one supported in this version) */
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/* basic functions */
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extern int zlib_deflate_workspacesize (int windowBits, int memLevel);
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/*
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Returns the number of bytes that needs to be allocated for a per-
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stream workspace with the specified parameters. A pointer to this
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number of bytes should be returned in stream->workspace before
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you call zlib_deflateInit() or zlib_deflateInit2(). If you call
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zlib_deflateInit(), specify windowBits = MAX_WBITS and memLevel =
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MAX_MEM_LEVEL here. If you call zlib_deflateInit2(), the windowBits
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and memLevel parameters passed to zlib_deflateInit2() must not
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exceed those passed here.
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*/
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/*
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extern int deflateInit (z_streamp strm, int level);
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Initializes the internal stream state for compression. The fields
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zalloc, zfree and opaque must be initialized before by the caller.
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If zalloc and zfree are set to NULL, deflateInit updates them to
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use default allocation functions.
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The compression level must be Z_DEFAULT_COMPRESSION, or between 0 and 9:
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1 gives best speed, 9 gives best compression, 0 gives no compression at
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all (the input data is simply copied a block at a time).
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Z_DEFAULT_COMPRESSION requests a default compromise between speed and
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compression (currently equivalent to level 6).
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deflateInit returns Z_OK if success, Z_MEM_ERROR if there was not
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enough memory, Z_STREAM_ERROR if level is not a valid compression level,
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Z_VERSION_ERROR if the zlib library version (zlib_version) is incompatible
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with the version assumed by the caller (ZLIB_VERSION).
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msg is set to null if there is no error message. deflateInit does not
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perform any compression: this will be done by deflate().
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*/
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extern int zlib_deflate (z_streamp strm, int flush);
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/*
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deflate compresses as much data as possible, and stops when the input
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buffer becomes empty or the output buffer becomes full. It may introduce some
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output latency (reading input without producing any output) except when
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forced to flush.
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The detailed semantics are as follows. deflate performs one or both of the
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following actions:
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- Compress more input starting at next_in and update next_in and avail_in
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accordingly. If not all input can be processed (because there is not
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enough room in the output buffer), next_in and avail_in are updated and
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processing will resume at this point for the next call of deflate().
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- Provide more output starting at next_out and update next_out and avail_out
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accordingly. This action is forced if the parameter flush is non zero.
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Forcing flush frequently degrades the compression ratio, so this parameter
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should be set only when necessary (in interactive applications).
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Some output may be provided even if flush is not set.
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Before the call of deflate(), the application should ensure that at least
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one of the actions is possible, by providing more input and/or consuming
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more output, and updating avail_in or avail_out accordingly; avail_out
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should never be zero before the call. The application can consume the
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compressed output when it wants, for example when the output buffer is full
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(avail_out == 0), or after each call of deflate(). If deflate returns Z_OK
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and with zero avail_out, it must be called again after making room in the
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output buffer because there might be more output pending.
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If the parameter flush is set to Z_SYNC_FLUSH, all pending output is
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flushed to the output buffer and the output is aligned on a byte boundary, so
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that the decompressor can get all input data available so far. (In particular
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avail_in is zero after the call if enough output space has been provided
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before the call.) Flushing may degrade compression for some compression
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algorithms and so it should be used only when necessary.
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If flush is set to Z_FULL_FLUSH, all output is flushed as with
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Z_SYNC_FLUSH, and the compression state is reset so that decompression can
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restart from this point if previous compressed data has been damaged or if
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random access is desired. Using Z_FULL_FLUSH too often can seriously degrade
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the compression.
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If deflate returns with avail_out == 0, this function must be called again
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with the same value of the flush parameter and more output space (updated
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avail_out), until the flush is complete (deflate returns with non-zero
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avail_out).
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If the parameter flush is set to Z_FINISH, pending input is processed,
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pending output is flushed and deflate returns with Z_STREAM_END if there
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was enough output space; if deflate returns with Z_OK, this function must be
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called again with Z_FINISH and more output space (updated avail_out) but no
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more input data, until it returns with Z_STREAM_END or an error. After
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deflate has returned Z_STREAM_END, the only possible operations on the
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stream are deflateReset or deflateEnd.
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Z_FINISH can be used immediately after deflateInit if all the compression
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is to be done in a single step. In this case, avail_out must be at least
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0.1% larger than avail_in plus 12 bytes. If deflate does not return
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Z_STREAM_END, then it must be called again as described above.
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deflate() sets strm->adler to the adler32 checksum of all input read
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so far (that is, total_in bytes).
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deflate() may update data_type if it can make a good guess about
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the input data type (Z_ASCII or Z_BINARY). In doubt, the data is considered
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binary. This field is only for information purposes and does not affect
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the compression algorithm in any manner.
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deflate() returns Z_OK if some progress has been made (more input
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processed or more output produced), Z_STREAM_END if all input has been
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consumed and all output has been produced (only when flush is set to
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Z_FINISH), Z_STREAM_ERROR if the stream state was inconsistent (for example
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if next_in or next_out was NULL), Z_BUF_ERROR if no progress is possible
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(for example avail_in or avail_out was zero).
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*/
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extern int zlib_deflateEnd (z_streamp strm);
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/*
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All dynamically allocated data structures for this stream are freed.
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This function discards any unprocessed input and does not flush any
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pending output.
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deflateEnd returns Z_OK if success, Z_STREAM_ERROR if the
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stream state was inconsistent, Z_DATA_ERROR if the stream was freed
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prematurely (some input or output was discarded). In the error case,
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msg may be set but then points to a static string (which must not be
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deallocated).
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*/
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extern int zlib_inflate_workspacesize (void);
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/*
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Returns the number of bytes that needs to be allocated for a per-
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stream workspace. A pointer to this number of bytes should be
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returned in stream->workspace before calling zlib_inflateInit().
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*/
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/*
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extern int zlib_inflateInit (z_streamp strm);
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Initializes the internal stream state for decompression. The fields
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next_in, avail_in, and workspace must be initialized before by
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the caller. If next_in is not NULL and avail_in is large enough (the exact
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value depends on the compression method), inflateInit determines the
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compression method from the zlib header and allocates all data structures
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accordingly; otherwise the allocation will be deferred to the first call of
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inflate. If zalloc and zfree are set to NULL, inflateInit updates them to
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use default allocation functions.
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inflateInit returns Z_OK if success, Z_MEM_ERROR if there was not enough
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memory, Z_VERSION_ERROR if the zlib library version is incompatible with the
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version assumed by the caller. msg is set to null if there is no error
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message. inflateInit does not perform any decompression apart from reading
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the zlib header if present: this will be done by inflate(). (So next_in and
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avail_in may be modified, but next_out and avail_out are unchanged.)
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*/
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extern int zlib_inflate (z_streamp strm, int flush);
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/*
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inflate decompresses as much data as possible, and stops when the input
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buffer becomes empty or the output buffer becomes full. It may introduce
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some output latency (reading input without producing any output) except when
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forced to flush.
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The detailed semantics are as follows. inflate performs one or both of the
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following actions:
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- Decompress more input starting at next_in and update next_in and avail_in
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accordingly. If not all input can be processed (because there is not
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enough room in the output buffer), next_in is updated and processing
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will resume at this point for the next call of inflate().
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- Provide more output starting at next_out and update next_out and avail_out
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accordingly. inflate() provides as much output as possible, until there
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is no more input data or no more space in the output buffer (see below
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about the flush parameter).
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Before the call of inflate(), the application should ensure that at least
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one of the actions is possible, by providing more input and/or consuming
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more output, and updating the next_* and avail_* values accordingly.
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The application can consume the uncompressed output when it wants, for
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example when the output buffer is full (avail_out == 0), or after each
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call of inflate(). If inflate returns Z_OK and with zero avail_out, it
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must be called again after making room in the output buffer because there
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might be more output pending.
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The flush parameter of inflate() can be Z_NO_FLUSH, Z_SYNC_FLUSH,
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Z_FINISH, or Z_BLOCK. Z_SYNC_FLUSH requests that inflate() flush as much
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output as possible to the output buffer. Z_BLOCK requests that inflate() stop
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if and when it gets to the next deflate block boundary. When decoding the
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zlib or gzip format, this will cause inflate() to return immediately after
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the header and before the first block. When doing a raw inflate, inflate()
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will go ahead and process the first block, and will return when it gets to
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the end of that block, or when it runs out of data.
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The Z_BLOCK option assists in appending to or combining deflate streams.
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Also to assist in this, on return inflate() will set strm->data_type to the
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number of unused bits in the last byte taken from strm->next_in, plus 64
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if inflate() is currently decoding the last block in the deflate stream,
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plus 128 if inflate() returned immediately after decoding an end-of-block
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code or decoding the complete header up to just before the first byte of the
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deflate stream. The end-of-block will not be indicated until all of the
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uncompressed data from that block has been written to strm->next_out. The
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number of unused bits may in general be greater than seven, except when
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bit 7 of data_type is set, in which case the number of unused bits will be
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less than eight.
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inflate() should normally be called until it returns Z_STREAM_END or an
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error. However if all decompression is to be performed in a single step
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(a single call of inflate), the parameter flush should be set to
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Z_FINISH. In this case all pending input is processed and all pending
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output is flushed; avail_out must be large enough to hold all the
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uncompressed data. (The size of the uncompressed data may have been saved
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by the compressor for this purpose.) The next operation on this stream must
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be inflateEnd to deallocate the decompression state. The use of Z_FINISH
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is never required, but can be used to inform inflate that a faster approach
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may be used for the single inflate() call.
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In this implementation, inflate() always flushes as much output as
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possible to the output buffer, and always uses the faster approach on the
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first call. So the only effect of the flush parameter in this implementation
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is on the return value of inflate(), as noted below, or when it returns early
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because Z_BLOCK is used.
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If a preset dictionary is needed after this call (see inflateSetDictionary
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below), inflate sets strm->adler to the adler32 checksum of the dictionary
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chosen by the compressor and returns Z_NEED_DICT; otherwise it sets
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strm->adler to the adler32 checksum of all output produced so far (that is,
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total_out bytes) and returns Z_OK, Z_STREAM_END or an error code as described
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below. At the end of the stream, inflate() checks that its computed adler32
|
|
checksum is equal to that saved by the compressor and returns Z_STREAM_END
|
|
only if the checksum is correct.
|
|
|
|
inflate() will decompress and check either zlib-wrapped or gzip-wrapped
|
|
deflate data. The header type is detected automatically. Any information
|
|
contained in the gzip header is not retained, so applications that need that
|
|
information should instead use raw inflate, see inflateInit2() below, or
|
|
inflateBack() and perform their own processing of the gzip header and
|
|
trailer.
|
|
|
|
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), Z_STREAM_ERROR if the stream structure was inconsistent (for example
|
|
if next_in or next_out was NULL), Z_MEM_ERROR if there was not enough memory,
|
|
Z_BUF_ERROR if no progress is possible or if there was not enough room in the
|
|
output buffer when Z_FINISH is used. 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 desired.
|
|
*/
|
|
|
|
|
|
extern int zlib_inflateEnd (z_streamp strm);
|
|
/*
|
|
All dynamically allocated data structures for this stream are freed.
|
|
This function discards any unprocessed input and does not flush any
|
|
pending output.
|
|
|
|
inflateEnd returns Z_OK if success, Z_STREAM_ERROR if the stream state
|
|
was inconsistent. In the error case, msg may be set but then points to a
|
|
static string (which must not be deallocated).
|
|
*/
|
|
|
|
/* Advanced functions */
|
|
|
|
/*
|
|
The following functions are needed only in some special applications.
|
|
*/
|
|
|
|
/*
|
|
extern int deflateInit2 (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.
|
|
|
|
The memLevel parameter specifies how much memory should be allocated
|
|
for the internal compression state. memLevel=1 uses minimum memory but
|
|
is slow and reduces compression ratio; memLevel=9 uses maximum memory
|
|
for optimal speed. The default value is 8. See zconf.h for total memory
|
|
usage as a function of windowBits and memLevel.
|
|
|
|
The strategy parameter is used to tune the compression algorithm. Use the
|
|
value Z_DEFAULT_STRATEGY for normal data, Z_FILTERED for data produced by a
|
|
filter (or predictor), or Z_HUFFMAN_ONLY to force Huffman encoding only (no
|
|
string match). Filtered data consists mostly of small values with a
|
|
somewhat random distribution. In this case, the compression algorithm is
|
|
tuned to compress them better. The effect of Z_FILTERED is to force more
|
|
Huffman coding and less string matching; it is somewhat intermediate
|
|
between Z_DEFAULT and Z_HUFFMAN_ONLY. The strategy parameter only affects
|
|
the compression ratio but not the correctness of the compressed output even
|
|
if it is not set appropriately.
|
|
|
|
deflateInit2 returns Z_OK if success, Z_MEM_ERROR if there was not enough
|
|
memory, Z_STREAM_ERROR if a parameter is invalid (such as an invalid
|
|
method). msg is set to null if there is no error message. deflateInit2 does
|
|
not perform any compression: this will be done by deflate().
|
|
*/
|
|
|
|
extern int zlib_deflateReset (z_streamp strm);
|
|
/*
|
|
This function is equivalent to deflateEnd followed by deflateInit,
|
|
but does not free and reallocate all the internal compression state.
|
|
The stream will keep the same compression level and any other attributes
|
|
that may have been set by deflateInit2.
|
|
|
|
deflateReset returns Z_OK if success, or Z_STREAM_ERROR if the source
|
|
stream state was inconsistent (such as zalloc or state being NULL).
|
|
*/
|
|
|
|
static inline unsigned long deflateBound(unsigned long s)
|
|
{
|
|
return s + ((s + 7) >> 3) + ((s + 63) >> 6) + 11;
|
|
}
|
|
|
|
/*
|
|
extern int inflateInit2 (z_streamp strm, int windowBits);
|
|
|
|
This is another version of inflateInit with an extra parameter. The
|
|
fields next_in, avail_in, zalloc, zfree and opaque must be initialized
|
|
before by the caller.
|
|
|
|
The windowBits parameter is the base two logarithm of the maximum window
|
|
size (the size of the history buffer). It should be in the range 8..15 for
|
|
this version of the library. The default value is 15 if inflateInit is used
|
|
instead. windowBits must be greater than or equal to the windowBits value
|
|
provided to deflateInit2() while compressing, or it must be equal to 15 if
|
|
deflateInit2() was not used. If a compressed stream with a larger window
|
|
size is given as input, inflate() will return with the error code
|
|
Z_DATA_ERROR instead of trying to allocate a larger window.
|
|
|
|
windowBits can also be -8..-15 for raw inflate. In this case, -windowBits
|
|
determines the window size. inflate() will then process raw deflate data,
|
|
not looking for a zlib or gzip header, not generating a check value, and not
|
|
looking for any check values for comparison at the end of the stream. This
|
|
is for use with other formats that use the deflate compressed data format
|
|
such as zip. Those formats provide their own check values. If a custom
|
|
format is developed using the raw deflate format for compressed data, it is
|
|
recommended that a check value such as an adler32 or a crc32 be applied to
|
|
the uncompressed data as is done in the zlib, gzip, and zip formats. For
|
|
most applications, the zlib format should be used as is. Note that comments
|
|
above on the use in deflateInit2() applies to the magnitude of windowBits.
|
|
|
|
windowBits can also be greater than 15 for optional gzip decoding. Add
|
|
32 to windowBits to enable zlib and gzip decoding with automatic header
|
|
detection, or add 16 to decode only the gzip format (the zlib format will
|
|
return a Z_DATA_ERROR). If a gzip stream is being decoded, strm->adler is
|
|
a crc32 instead of an adler32.
|
|
|
|
inflateInit2 returns Z_OK if success, Z_MEM_ERROR if there was not enough
|
|
memory, Z_STREAM_ERROR if a parameter is invalid (such as a null strm). msg
|
|
is set to null if there is no error message. inflateInit2 does not perform
|
|
any decompression apart from reading the zlib header if present: this will
|
|
be done by inflate(). (So next_in and avail_in may be modified, but next_out
|
|
and avail_out are unchanged.)
|
|
*/
|
|
|
|
extern int zlib_inflateReset (z_streamp strm);
|
|
/*
|
|
This function is equivalent to inflateEnd followed by inflateInit,
|
|
but does not free and reallocate all the internal decompression state.
|
|
The stream will keep attributes that may have been set by inflateInit2.
|
|
|
|
inflateReset returns Z_OK if success, or Z_STREAM_ERROR if the source
|
|
stream state was inconsistent (such as zalloc or state being NULL).
|
|
*/
|
|
|
|
extern int zlib_inflateIncomp (z_stream *strm);
|
|
/*
|
|
This function adds the data at next_in (avail_in bytes) to the output
|
|
history without performing any output. There must be no pending output,
|
|
and the decompressor must be expecting to see the start of a block.
|
|
Calling this function is equivalent to decompressing a stored block
|
|
containing the data at next_in (except that the data is not output).
|
|
*/
|
|
|
|
#define zlib_deflateInit(strm, level) \
|
|
zlib_deflateInit2((strm), (level), Z_DEFLATED, MAX_WBITS, \
|
|
DEF_MEM_LEVEL, Z_DEFAULT_STRATEGY)
|
|
#define zlib_inflateInit(strm) \
|
|
zlib_inflateInit2((strm), DEF_WBITS)
|
|
|
|
extern int zlib_deflateInit2(z_streamp strm, int level, int method,
|
|
int windowBits, int memLevel,
|
|
int strategy);
|
|
extern int zlib_inflateInit2(z_streamp strm, int windowBits);
|
|
|
|
#if !defined(_Z_UTIL_H) && !defined(NO_DUMMY_DECL)
|
|
struct internal_state {int dummy;}; /* hack for buggy compilers */
|
|
#endif
|
|
|
|
/* Utility function: initialize zlib, unpack binary blob, clean up zlib,
|
|
* return len or negative error code. */
|
|
extern int zlib_inflate_blob(void *dst, unsigned dst_sz, const void *src, unsigned src_sz);
|
|
|
|
#endif /* _ZLIB_H */
|