utfutf.c (1208B)
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 11 * ANY 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 "plan9.h" 17 #include "utf.h" 18 19 20 /* 21 * Return pointer to first occurrence of s2 in s1, 22 * 0 if none 23 */ 24 char* 25 utfutf(const char *s1, const char *s2) 26 { 27 const char *p; 28 long f, n1, n2; 29 Rune r; 30 31 n1 = chartorune(&r, s2); 32 f = r; 33 if(f <= Runesync) /* represents self */ 34 return strstr(s1, s2); 35 36 n2 = strlen(s2); 37 for(p=s1; p=utfrune(p, f); p+=n1) 38 if(strncmp(p, s2, n2) == 0) 39 return (char*)p; 40 return 0; 41 }