1 /* Searching a string for a character. 2 Copyright (C) 2007-2012 Free Software Foundation, Inc. 3 Written by Bruno Haible <bruno (at) clisp.org>, 2007. 4 5 This program is free software: you can redistribute it and/or modify 6 it under the terms of the GNU General Public License as published by 7 the Free Software Foundation; either version 3 of the License, or 8 (at your option) any later version. 9 10 This program is distributed in the hope that it will be useful, 11 but WITHOUT ANY WARRANTY; without even the implied warranty of 12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 13 GNU General Public License for more details. 14 15 You should have received a copy of the GNU General Public License 16 along with this program. If not, see <http://www.gnu.org/licenses/>. */ 17 18 #include <config.h> 19 20 /* Specification. */ 21 #include <string.h> 22 23 #include "mbuiter.h" 24 25 /* Locate the first single-byte character C in the character string STRING, 26 and return a pointer to it. Return NULL if C is not found in STRING. */ 27 char * 28 mbschr (const char *string, int c) 29 { 30 if (MB_CUR_MAX > 1 31 /* Optimization: We know that ASCII characters < 0x30 don't occur as 32 part of multibyte characters longer than 1 byte. Hence, if c < 0x30, 33 the faster unibyte loop can be used. */ 34 && (unsigned char) c >= 0x30) 35 { 36 mbui_iterator_t iter; 37 38 for (mbui_init (iter, string);; mbui_advance (iter)) 39 { 40 if (!mbui_avail (iter)) 41 goto notfound; 42 if (mb_len (mbui_cur (iter)) == 1 43 && (unsigned char) * mbui_cur_ptr (iter) == (unsigned char) c) 44 break; 45 } 46 return (char *) mbui_cur_ptr (iter); 47 notfound: 48 return NULL; 49 } 50 else 51 return strchr (string, c); 52 } 53
