1 /* Search character in UTF-8 string.
2 Copyright (C) 1999, 2002, 2006-2007, 2009-2010 Free Software Foundation,
4 Written by Bruno Haible <bruno@clisp.org>, 2002.
6 This program is free software: you can redistribute it and/or modify it
7 under the terms of the GNU Lesser General Public License as published
8 by the Free Software Foundation; either version 3 of the License, or
9 (at your option) any later version.
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 Lesser General Public License for more details.
16 You should have received a copy of the GNU Lesser General Public License
17 along with this program. If not, see <http://www.gnu.org/licenses/>. */
27 u8_strchr (const uint8_t *s, ucs4_t uc)
37 /* Unoptimized code. */
51 strchr() is often so well optimized, that it's worth the
52 added function call. */
53 return (uint8_t *) strchr ((const char *) s, c0);
57 /* Loops equivalent to strstr, optimized for a specific length (2, 3, 4)
58 of the needle. We use an algorithm similar to Boyer-Moore which
59 is documented in lib/unistr/u8-chr.c. There is additional
60 complication because we need to check after every byte for
61 a NUL byte, but the idea is the same. */
62 switch (u8_uctomb_aux (c, uc, 6))
103 if (*s == 0 || s[1] == 0)
115 if (s[1] == c1 && *s == c0)
116 return (uint8_t *) s;
150 if (*s == 0 || s[1] == 0 || s[2] == 0)
163 if (s[2] == c2 && s[1] == c1 && *s == c0)
164 return (uint8_t *) s;