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freebsd-skq/usr.bin/tr/cset.h

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Add support for multibyte characters. The challenge here was to use data structures that scale better with large character sets, instead of arrays indexed by character value: - Sets of characters to delete/squeeze are stored in a new "cset" structure, which is implemented as a splay tree of extents. This structure has the ability to store character classes (ala wctype(3)), but this is not currently fully utilized. - Mappings between characters are stored in a new "cmap" structure, which is also a splay tree. - The parser no longer builds arrays containing all the characters in a particular class; instead, next() determines them on-the-fly using nextwctype(3).
2004-07-09 02:08:07 +00:00
/*-
various: general adoption of SPDX licensing ID tags. Mainly focus on files that use BSD 2-Clause license, however the tool I was using misidentified many licenses so this was mostly a manual - error prone - task. The Software Package Data Exchange (SPDX) group provides a specification to make it easier for automated tools to detect and summarize well known opensource licenses. We are gradually adopting the specification, noting that the tags are considered only advisory and do not, in any way, superceed or replace the license texts. No functional change intended.
2017-11-27 15:37:16 +00:00
* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
*
Add support for multibyte characters. The challenge here was to use data structures that scale better with large character sets, instead of arrays indexed by character value: - Sets of characters to delete/squeeze are stored in a new "cset" structure, which is implemented as a splay tree of extents. This structure has the ability to store character classes (ala wctype(3)), but this is not currently fully utilized. - Mappings between characters are stored in a new "cmap" structure, which is also a splay tree. - The parser no longer builds arrays containing all the characters in a particular class; instead, next() determines them on-the-fly using nextwctype(3).
2004-07-09 02:08:07 +00:00
* Copyright (c) 2004 Tim J. Robbins.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $FreeBSD$
*/
#ifndef CSET_H
#define CSET_H
#include <stdbool.h>
Revert most part of 200420 as requested, as more review and polish is needed.
2009-12-13 03:14:06 +00:00
#include <wchar.h>
Add support for multibyte characters. The challenge here was to use data structures that scale better with large character sets, instead of arrays indexed by character value: - Sets of characters to delete/squeeze are stored in a new "cset" structure, which is implemented as a splay tree of extents. This structure has the ability to store character classes (ala wctype(3)), but this is not currently fully utilized. - Mappings between characters are stored in a new "cmap" structure, which is also a splay tree. - The parser no longer builds arrays containing all the characters in a particular class; instead, next() determines them on-the-fly using nextwctype(3).
2004-07-09 02:08:07 +00:00
#include <wctype.h>
struct csnode {
wchar_t csn_min;
wchar_t csn_max;
struct csnode *csn_left;
struct csnode *csn_right;
};
struct csclass {
wctype_t csc_type;
bool csc_invert;
struct csclass *csc_next;
};
struct cset {
#define CS_CACHE_SIZE 256
bool cs_cache[CS_CACHE_SIZE];
bool cs_havecache;
struct csclass *cs_classes;
struct csnode *cs_root;
bool cs_invert;
};
bool cset_addclass(struct cset *, wctype_t, bool);
struct cset * cset_alloc(void);
bool cset_add(struct cset *, wchar_t);
void cset_invert(struct cset *);
bool cset_in_hard(struct cset *, wchar_t);
void cset_cache(struct cset *);
static __inline bool
cset_in(struct cset *cs, wchar_t ch)
{
if (ch < CS_CACHE_SIZE && cs->cs_havecache)
return (cs->cs_cache[ch]);
return (cset_in_hard(cs, ch));
}
#endif /* CSET_H */
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