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Commit	Line	Data
	1	/*
	2	* Copyright (c) 2000-2013 Apple Inc. All rights reserved.
	3	*
	4	* @APPLE_OSREFERENCE_LICENSE_HEADER_START@
	5	*
	6	* This file contains Original Code and/or Modifications of Original Code
	7	* as defined in and that are subject to the Apple Public Source License
	8	* Version 2.0 (the 'License'). You may not use this file except in
	9	* compliance with the License. The rights granted to you under the License
	10	* may not be used to create, or enable the creation or redistribution of,
	11	* unlawful or unlicensed copies of an Apple operating system, or to
	12	* circumvent, violate, or enable the circumvention or violation of, any
	13	* terms of an Apple operating system software license agreement.
	14	*
	15	* Please obtain a copy of the License at
	16	* http://www.opensource.apple.com/apsl/ and read it before using this file.
	17	*
	18	* The Original Code and all software distributed under the License are
	19	* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
	20	* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
	21	* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
	22	* FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
	23	* Please see the License for the specific language governing rights and
	24	* limitations under the License.
	25	*
	26	* @APPLE_OSREFERENCE_LICENSE_HEADER_END@
	27	*/
	28
	29	/* direct-mapped partial matching compressor with simple 22/10 split
	30	*
	31	* Compresses buffers using a dictionary based match and partial match
	32	* (high bits only or full match) scheme.
	33	*
	34	* Paul Wilson -- wilson@cs.utexas.edu
	35	* Scott F. Kaplan -- sfkaplan@cs.utexas.edu
	36	* September 1997
	37	*/
	38
	39	/* compressed output format, in memory order
	40	* 1. a four-word HEADER containing four one-word values:
	41	* i. a one-word code saying what algorithm compressed the data
	42	* ii. an integer WORD offset into the page saying
	43	* where the queue position area starts
	44	* iii. an integer WORD offset into the page saying where
	45	* the low-bits area starts
	46	* iv. an integer WORD offset into the page saying where the
	47	* low-bits area ends
	48	*
	49	* 2. a 64-word TAGS AREA holding one two-bit tag for each word in
	50	* the original (1024-word) page, packed 16 per word
	51	*
	52	* 3. a variable-sized FULL WORDS AREA (always word aligned and an
	53	* integral number of words) holding full-word patterns that
	54	* were not in the dictionary when encoded (i.e., dictionary misses)
	55	*
	56	* 4. a variable-sized QUEUE POSITIONS AREA (always word aligned and
	57	* an integral number of words) holding four-bit queue positions,
	58	* packed eight per word.
	59	*
	60	* 5. a variable-sized LOW BITS AREA (always word aligned and an
	61	* integral number of words) holding ten-bit low-bit patterns
	62	* (from partial matches), packed three per word.
	63	*/
	64
	65	#ifdef __cplusplus
	66	extern "C" {
	67	#endif
	68
	69	#include <mach/vm_param.h>
	70
	71
	72	#define WKdm_SCRATCH_BUF_SIZE PAGE_SIZE
	73
	74	typedef unsigned int WK_word;
	75
	76
	77	void
	78	WKdm_decompress_new (WK_word* src_buf,
	79	WK_word* dest_buf,
	80	WK_word* scratch,
	81	unsigned int bytes);
	82	int
	83	WKdm_compress_new (WK_word* src_buf,
	84	WK_word* dest_buf,
	85	WK_word* scratch,
	86	unsigned int limit);
	87
	88	#ifdef __cplusplus
	89	} /* extern "C" */
	90	#endif