xref: /plan9/sys/src/cmd/unix/drawterm/libc/utfutf.c (revision 8ccd4a6360d974db7bd7bbd4f37e7018419ea908)
1 #include <u.h>
2 #include <libc.h>
3 
4 
5 /*
6  * Return pointer to first occurrence of s2 in s1,
7  * 0 if none
8  */
9 char*
utfutf(char * s1,char * s2)10 utfutf(char *s1, char *s2)
11 {
12 	char *p;
13 	long f, n1, n2;
14 	Rune r;
15 
16 	n1 = chartorune(&r, s2);
17 	f = r;
18 	if(f <= Runesync)		/* represents self */
19 		return strstr(s1, s2);
20 
21 	n2 = strlen(s2);
22 	for(p=s1; (p=utfrune(p, f)); p+=n1)
23 		if(strncmp(p, s2, n2) == 0)
24 			return p;
25 	return 0;
26 }
27