1 /* 2 * The authors of this software are Rob Pike and Ken Thompson. 3 * Copyright (c) 2002 by Lucent Technologies. 4 * Permission to use, copy, modify, and distribute this software for any 5 * purpose without fee is hereby granted, provided that this entire notice 6 * is included in all copies of any software which is or includes a copy 7 * or modification of this software and in all copies of the supporting 8 * documentation for such software. 9 * THIS SOFTWARE IS BEING PROVIDED "AS IS", WITHOUT ANY EXPRESS OR IMPLIED 10 * WARRANTY. IN PARTICULAR, NEITHER THE AUTHORS NOR LUCENT TECHNOLOGIES MAKE ANY 11 * REPRESENTATION OR WARRANTY OF ANY KIND CONCERNING THE MERCHANTABILITY 12 * OF THIS SOFTWARE OR ITS FITNESS FOR ANY PARTICULAR PURPOSE. 13 */ 14 #include <stdarg.h> 15 #include <string.h> 16 #include "utf.h" 17 #include "utfdef.h" 18 19 const 20 char* 21 utfrune(const char *s, Rune c) 22 { 23 long c1; 24 Rune r; 25 int n; 26 27 if(c < Runesync) /* not part of utf sequence */ 28 return strchr(s, c); 29 30 for(;;) { 31 c1 = *(uchar*)s; 32 if(c1 < Runeself) { /* one byte rune */ 33 if(c1 == 0) 34 return 0; 35 if(c1 == c) 36 return s; 37 s++; 38 continue; 39 } 40 n = chartorune(&r, s); 41 if(r == c) 42 return s; 43 s += n; 44 } 45 return 0; 46 } 47
