wmii/libutf/utfnlen.c

42 lines
1.1 KiB
C

/*
* The authors of this software are Rob Pike and Ken Thompson.
* Copyright (c) 2002 by Lucent Technologies.
* Permission to use, copy, modify, and distribute this software for any
* purpose without fee is hereby granted, provided that this entire notice
* is included in all copies of any software which is or includes a copy
* or modification of this software and in all copies of the supporting
* documentation for such software.
* THIS SOFTWARE IS BEING PROVIDED "AS IS", WITHOUT ANY EXPRESS OR IMPLIED
* WARRANTY. IN PARTICULAR, NEITHER THE AUTHORS NOR LUCENT TECHNOLOGIES MAKE
* ANY REPRESENTATION OR WARRANTY OF ANY KIND CONCERNING THE MERCHANTABILITY
* OF THIS SOFTWARE OR ITS FITNESS FOR ANY PARTICULAR PURPOSE.
*/
#include <stdarg.h>
#include <string.h>
#include "plan9.h"
#include "utf.h"
int
utfnlen(char *s, long m)
{
int c;
long n;
Rune rune;
char *es;
es = s + m;
for(n = 0; s < es; n++) {
c = *(uchar*)s;
if(c < Runeself){
if(c == '\0')
break;
s++;
continue;
}
if(!fullrune(s, es-s))
break;
s += chartorune(&rune, s);
}
return n;
}