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Diffstat (limited to '')
-rw-r--r-- | libraries/liblunicode/utbm/utbm.c | 472 |
1 files changed, 472 insertions, 0 deletions
diff --git a/libraries/liblunicode/utbm/utbm.c b/libraries/liblunicode/utbm/utbm.c new file mode 100644 index 0000000..458305c --- /dev/null +++ b/libraries/liblunicode/utbm/utbm.c @@ -0,0 +1,472 @@ +/* $OpenLDAP$ */ +/* This work is part of OpenLDAP Software <http://www.openldap.org/>. + * + * Copyright 1998-2022 The OpenLDAP Foundation. + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted only as authorized by the OpenLDAP + * Public License. + * + * A copy of this license is available in file LICENSE in the + * top-level directory of the distribution or, alternatively, at + * <http://www.OpenLDAP.org/license.html>. + */ +/* Copyright 1997, 1998, 1999 Computing Research Labs, + * New Mexico State University + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the "Software"), + * to deal in the Software without restriction, including without limitation + * the rights to use, copy, modify, merge, publish, distribute, sublicense, + * and/or sell copies of the Software, and to permit persons to whom the + * Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in + * all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * THE COMPUTING RESEARCH LAB OR NEW MEXICO STATE UNIVERSITY BE LIABLE FOR ANY + * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT + * OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR + * THE USE OR OTHER DEALINGS IN THE SOFTWARE. + */ +/* $Id: utbm.c,v 1.1 1999/09/21 15:45:17 mleisher Exp $ */ + +/* + * Assumptions: + * 1. Case conversions of UTF-16 characters must also be UTF-16 characters. + * 2. Case conversions are all one-to-one. + * 3. Text and pattern have already been normalized in some fashion. + */ + +#include <stdlib.h> +#include <unistd.h> +#include <string.h> +#include "utbm.h" + +/* + * Single pattern character. + */ +typedef struct { + ucs4_t lc; + ucs4_t uc; + ucs4_t tc; +} _utbm_char_t; + +typedef struct { + _utbm_char_t *ch; + unsigned long skip; +} _utbm_skip_t; + +typedef struct _utbm_pattern_t { + unsigned long flags; + + _utbm_char_t *pat; + unsigned long pat_used; + unsigned long pat_size; + unsigned long patlen; + + _utbm_skip_t *skip; + unsigned long skip_used; + unsigned long skip_size; + + unsigned long md4; +} _utbm_pattern_t; + +/************************************************************************* + * + * Support functions. + * + *************************************************************************/ + +/* + * Routine to look up the skip value for a character. + */ +static unsigned long +_utbm_skip(utbm_pattern_t p, ucs2_t *start, ucs2_t *end) +{ + unsigned long i; + ucs4_t c1, c2; + _utbm_skip_t *sp; + + if (start >= end) + return 0; + + c1 = *start; + c2 = (start + 1 < end) ? *(start + 1) : ~0; + if (0xd800 <= c1 && c1 <= 0xdbff && 0xdc00 <= c2 && c2 <= 0xdfff) + c1 = 0x10000 + (((c1 & 0x03ff) << 10) | (c2 & 0x03ff)); + + for (i = 0, sp = p->skip; i < p->skip_used; i++, sp++) { + if (!((c1 ^ sp->ch->uc) & (c1 ^ sp->ch->lc) & (c1 ^ sp->ch->tc))) { + return ((unsigned long) (end - start) < sp->skip) ? + end - start : sp->skip; + } + } + return p->patlen; +} + +static int +_utbm_match(utbm_pattern_t pat, ucs2_t *text, ucs2_t *start, ucs2_t *end, + unsigned long *match_start, unsigned long *match_end) +{ + int check_space; + ucs4_t c1, c2; + unsigned long count; + _utbm_char_t *cp; + + /* + * Set the potential match endpoint first. + */ + *match_end = (start - text) + 1; + + c1 = *start; + c2 = (start + 1 < end) ? *(start + 1) : ~0; + if (0xd800 <= c1 && c1 <= 0xdbff && 0xdc00 <= c2 && c2 <= 0xdfff) { + c1 = 0x10000 + (((c1 & 0x03ff) << 10) | (c2 & 0x03ff)); + /* + * Adjust the match end point to occur after the UTF-16 character. + */ + *match_end = *match_end + 1; + } + + if (pat->pat_used == 1) { + *match_start = start - text; + return 1; + } + + /* + * Compare backward. + */ + cp = pat->pat + (pat->pat_used - 1); + + for (count = pat->patlen; start > text && count > 0;) { + /* + * Ignore non-spacing characters if indicated. + */ + if (pat->flags & UTBM_IGNORE_NONSPACING) { + while (start > text && _utbm_nonspacing(c1)) { + c2 = *--start; + c1 = (start - 1 > text) ? *(start - 1) : ~0; + if (0xdc00 <= c2 && c2 <= 0xdfff && + 0xd800 <= c1 && c1 <= 0xdbff) { + c1 = 0x10000 + (((c1 & 0x03ff) << 10) | (c2 & 0x03ff)); + start--; + } else + c1 = c2; + } + } + + /* + * Handle space compression if indicated. + */ + if (pat->flags & UTBM_SPACE_COMPRESS) { + check_space = 0; + while (start > text && + (_utbm_isspace(c1, 1) || _utbm_iscntrl(c1))) { + check_space = _utbm_isspace(c1, 1); + c2 = *--start; + c1 = (start - 1 > text) ? *(start - 1) : ~0; + if (0xdc00 <= c2 && c2 <= 0xdfff && + 0xd800 <= c1 && c1 <= 0xdbff) { + c1 = 0x10000 + (((c1 & 0x03ff) << 10) | (c2 & 0x03ff)); + start--; + } else + c1 = c2; + } + /* + * Handle things if space compression was indicated and one or + * more member characters were found. + */ + if (check_space) { + if (cp->uc != ' ') + return 0; + cp--; + count--; + } + } + + /* + * Handle the normal comparison cases. + */ + if (count > 0 && ((c1 ^ cp->uc) & (c1 ^ cp->lc) & (c1 ^ cp->tc))) + return 0; + + count -= (c1 >= 0x10000) ? 2 : 1; + if (count > 0) { + cp--; + + /* + * Get the next preceding character. + */ + if (start > text) { + c2 = *--start; + c1 = (start - 1 > text) ? *(start - 1) : ~0; + if (0xdc00 <= c2 && c2 <= 0xdfff && + 0xd800 <= c1 && c1 <= 0xdbff) { + c1 = 0x10000 + (((c1 & 0x03ff) << 10) | (c2 & 0x03ff)); + start--; + } else + c1 = c2; + } + } + } + + /* + * Set the match start position. + */ + *match_start = start - text; + return 1; +} + +/************************************************************************* + * + * API. + * + *************************************************************************/ + +utbm_pattern_t +utbm_create_pattern(void) +{ + utbm_pattern_t p; + + p = (utbm_pattern_t) malloc(sizeof(_utbm_pattern_t)); + (void) memset((char *) p, '\0', sizeof(_utbm_pattern_t)); + return p; +} + +void +utbm_free_pattern(utbm_pattern_t pattern) +{ + if (pattern == 0) + return; + + if (pattern->pat_size > 0) + free((char *) pattern->pat); + + if (pattern->skip_size > 0) + free((char *) pattern->skip); + + free((char *) pattern); +} + +void +utbm_compile(ucs2_t *pat, unsigned long patlen, unsigned long flags, + utbm_pattern_t p) +{ + int have_space; + unsigned long i, j, k, slen; + _utbm_char_t *cp; + _utbm_skip_t *sp; + ucs4_t c1, c2, sentinel; + + if (p == 0 || pat == 0 || *pat == 0 || patlen == 0) + return; + + /* + * Reset the pattern buffer. + */ + p->patlen = p->pat_used = p->skip_used = 0; + + /* + * Set the flags. + */ + p->flags = flags; + + /* + * Initialize the extra skip flag. + */ + p->md4 = 1; + + /* + * Allocate more storage if necessary. + */ + if (patlen > p->pat_size) { + if (p->pat_size == 0) { + p->pat = (_utbm_char_t *) malloc(sizeof(_utbm_char_t) * patlen); + p->skip = (_utbm_skip_t *) malloc(sizeof(_utbm_skip_t) * patlen); + } else { + p->pat = (_utbm_char_t *) + realloc((char *) p->pat, sizeof(_utbm_char_t) * patlen); + p->skip = (_utbm_skip_t *) + realloc((char *) p->skip, sizeof(_utbm_skip_t) * patlen); + } + p->pat_size = p->skip_size = patlen; + } + + /* + * Preprocess the pattern to remove controls (if specified) and determine + * case. + */ + for (have_space = 0, cp = p->pat, i = 0; i < patlen; i++) { + c1 = pat[i]; + c2 = (i + 1 < patlen) ? pat[i + 1] : ~0; + if (0xd800 <= c1 && c1 <= 0xdbff && 0xdc00 <= c2 && c2 <= 0xdfff) + c1 = 0x10000 + (((c1 & 0x03ff) << 10) | (c2 & 0x03ff)); + + /* + * Make sure the `have_space' flag is turned off if the character + * is not an appropriate one. + */ + if (!_utbm_isspace(c1, flags & UTBM_SPACE_COMPRESS)) + have_space = 0; + + /* + * If non-spacing characters should be ignored, do it here. + */ + if ((flags & UTBM_IGNORE_NONSPACING) && _utbm_nonspacing(c1)) + continue; + + /* + * Check if spaces and controls need to be compressed. + */ + if (flags & UTBM_SPACE_COMPRESS) { + if (_utbm_isspace(c1, 1)) { + if (!have_space) { + /* + * Add a space and set the flag. + */ + cp->uc = cp->lc = cp->tc = ' '; + cp++; + + /* + * Increase the real pattern length. + */ + p->patlen++; + sentinel = ' '; + have_space = 1; + } + continue; + } + + /* + * Ignore all control characters. + */ + if (_utbm_iscntrl(c1)) + continue; + } + + /* + * Add the character. + */ + if (flags & UTBM_CASEFOLD) { + cp->uc = _utbm_toupper(c1); + cp->lc = _utbm_tolower(c1); + cp->tc = _utbm_totitle(c1); + } else + cp->uc = cp->lc = cp->tc = c1; + + /* + * Set the sentinel character. + */ + sentinel = cp->uc; + + /* + * Move to the next character. + */ + cp++; + + /* + * Increase the real pattern length appropriately. + */ + p->patlen += (c1 >= 0x10000) ? 2 : 1; + + /* + * Increment the loop index for UTF-16 characters. + */ + i += (c1 >= 0x10000) ? 1 : 0; + + } + + /* + * Set the number of characters actually used. + */ + p->pat_used = cp - p->pat; + + /* + * Go through and construct the skip array and determine the actual length + * of the pattern in UCS2 terms. + */ + slen = p->patlen - 1; + cp = p->pat; + for (i = k = 0; i < p->pat_used; i++, cp++) { + /* + * Locate the character in the skip array. + */ + for (sp = p->skip, j = 0; + j < p->skip_used && sp->ch->uc != cp->uc; j++, sp++) ; + + /* + * If the character is not found, set the new skip element and + * increase the number of skip elements. + */ + if (j == p->skip_used) { + sp->ch = cp; + p->skip_used++; + } + + /* + * Set the updated skip value. If the character is UTF-16 and is + * not the last one in the pattern, add one to its skip value. + */ + sp->skip = slen - k; + if (cp->uc >= 0x10000 && k + 2 < slen) + sp->skip++; + + /* + * Set the new extra skip for the sentinel character. + */ + if (((cp->uc >= 0x10000 && k + 2 <= slen) || k + 1 <= slen) && + cp->uc == sentinel) + p->md4 = slen - k; + + /* + * Increase the actual index. + */ + k += (cp->uc >= 0x10000) ? 2 : 1; + } +} + +int +utbm_exec(utbm_pattern_t pat, ucs2_t *text, unsigned long textlen, + unsigned long *match_start, unsigned long *match_end) +{ + unsigned long k; + ucs2_t *start, *end; + + if (pat == 0 || pat->pat_used == 0 || text == 0 || textlen == 0 || + textlen < pat->patlen) + return 0; + + start = text + pat->patlen; + end = text + textlen; + + /* + * Adjust the start point if it points to a low surrogate. + */ + if (0xdc00 <= *start && *start <= 0xdfff && + 0xd800 <= *(start - 1) && *(start - 1) <= 0xdbff) + start--; + + while (start < end) { + while ((k = _utbm_skip(pat, start, end))) { + start += k; + if (start < end && 0xdc00 <= *start && *start <= 0xdfff && + 0xd800 <= *(start - 1) && *(start - 1) <= 0xdbff) + start--; + } + + if (start < end && + _utbm_match(pat, text, start, end, match_start, match_end)) + return 1; + + start += pat->md4; + if (start < end && 0xdc00 <= *start && *start <= 0xdfff && + 0xd800 <= *(start - 1) && *(start - 1) <= 0xdbff) + start--; + } + return 0; +} |