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/* Copyright (C) 2001-2006 Artifex Software, Inc.
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This software is provided AS-IS with no warranty, either express or
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This software is distributed under license and may not be copied, modified
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or distributed except as expressly authorized under the terms of that
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license. Refer to licensing information at http://www.artifex.com/
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or contact Artifex Software, Inc., 7 Mt. Lassen Drive - Suite A-134,
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San Rafael, CA 94903, U.S.A., +1(415)492-9861, for further information.
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/* $Id: inameidx.h 9043 2008-08-28 22:48:19Z giles $ */
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/* Name index definitions */
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#ifndef inameidx_INCLUDED
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# define inameidx_INCLUDED
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* The name table machinery has two slightly different configurations:
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* a faster one that limits the total number of names to 64K and allows
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* names up to 16K in size (EXTEND_NAMES == 0), and a slightly slower
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* one that limits the total to 64K << EXTEND_NAMES and and restricts names
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* to 16K >> EXTEND_NAMES. Max value of EXTEND_NAMES is 6, which corresponds
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* to 4M names of up to to 256 characters.
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#ifndef EXTEND_NAMES /* # of bits beyond 16 */
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# define EXTEND_NAMES 4
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/* Define the size of a name sub-table. */
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/* With NT_LOG2_SUB_SIZE >= 10 the subtable goes into a large chunk, */
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/* which names_trace_finish() cannot handle. */
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# define NT_LOG2_SUB_SIZE (8 + (EXTEND_NAMES >= 2))
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# define NT_SUB_SIZE (1 << NT_LOG2_SUB_SIZE)
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# define NT_SUB_INDEX_MASK (NT_SUB_SIZE - 1)
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* Define the first few entries of the name table. Entry 0 is left unused.
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* The entry with count = 1 is the entry for the 0-length name.
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* The next NT_1CHAR_SIZE entries (in count order) are 1-character names.
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#define NT_1CHAR_SIZE 128
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#define NT_1CHAR_FIRST 2
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#define NT_1CHAR_NAMES_DATA\
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0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,\
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16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31,\
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32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47,\
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48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63,\
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64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79,\
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80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95,\
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96, 97, 98, 99,100,101,102,103,104,105,106,107,108,109,110,111,\
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112,113,114,115,116,117,118,119,120,121,122,123,124,125,126,127
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/* ---------------- Name count/index mapping ---------------- */
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* We scramble the assignment order within a sub-table, so that
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* dictionary lookup doesn't have to scramble the index.
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* The scrambling algorithm must have three properties:
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* - It must map 0 to 0;
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* - It must only scramble the sub-table index;
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* - It must be a permutation on the sub-table index.
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* Something very simple works just fine.
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#define NAME_COUNT_TO_INDEX_FACTOR 23
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#define name_count_to_index(cnt)\
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(((cnt) & (-NT_SUB_SIZE)) +\
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(((cnt) * NAME_COUNT_TO_INDEX_FACTOR) & NT_SUB_INDEX_MASK))
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* The reverse permutation requires finding a number R such that
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* NAME_COUNT_TO_INDEX_FACTOR * R = 1 mod NT_SUB_SIZE.
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* The value given below works for NT_SUB_SIZE any power of 2 up to 4096.
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* This is not currently used anywhere.
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#define NAME_INDEX_TO_COUNT_FACTOR 1959
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#define name_index_to_count(nidx)\
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(((nidx) & (-NT_SUB_SIZE)) +\
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(((nidx) * NAME_INDEX_TO_COUNT_FACTOR) & NT_SUB_INDEX_MASK))
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#endif /* inameidx_INCLUDED */