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
19int
20utfnlen(const char *s, long m)
21{
22	int c;
23	long n;
24	Rune rune;
25	const char *es;
26
27	es = s + m;
28	for(n = 0; s < es; n++) {
29		c = *(uchar*)s;
30		if(c < Runeself){
31			if(c == '\0')
32				break;
33			s++;
34			continue;
35		}
36		if(!fullrune(s, es-s))
37			break;
38		s += chartorune(&rune, s);
39	}
40	return n;
41}
42