a

libc/utfutf.c

@@ -0,0 +1,26 @@
+#include <u.h>
+#include <libc.h>
+
+
+/*
+ * Return pointer to first occurrence of s2 in s1,
+ * 0 if none
+ */
+char*
+utfutf(char *s1, char *s2)
+{
+	char *p;
+	long f, n1, n2;
+	Rune r;
+
+	n1 = chartorune(&r, s2);
+	f = r;
+	if(f <= Runesync)		/* represents self */
+		return strstr(s1, s2);
+
+	n2 = strlen(s2);
+	for(p=s1; p=utfrune(p, f); p+=n1)
+		if(strncmp(p, s2, n2) == 0)
+			return p;
+	return 0;
+}