1*e72f3952SAlexander Dorokhine /*
2*e72f3952SAlexander Dorokhine * The authors of this software are Rob Pike and Ken Thompson.
3*e72f3952SAlexander Dorokhine * Copyright (c) 2002 by Lucent Technologies.
4*e72f3952SAlexander Dorokhine * Permission to use, copy, modify, and distribute this software for any
5*e72f3952SAlexander Dorokhine * purpose without fee is hereby granted, provided that this entire notice
6*e72f3952SAlexander Dorokhine * is included in all copies of any software which is or includes a copy
7*e72f3952SAlexander Dorokhine * or modification of this software and in all copies of the supporting
8*e72f3952SAlexander Dorokhine * documentation for such software.
9*e72f3952SAlexander Dorokhine * THIS SOFTWARE IS BEING PROVIDED "AS IS", WITHOUT ANY EXPRESS OR IMPLIED
10*e72f3952SAlexander Dorokhine * WARRANTY. IN PARTICULAR, NEITHER THE AUTHORS NOR LUCENT TECHNOLOGIES MAKE ANY
11*e72f3952SAlexander Dorokhine * REPRESENTATION OR WARRANTY OF ANY KIND CONCERNING THE MERCHANTABILITY
12*e72f3952SAlexander Dorokhine * OF THIS SOFTWARE OR ITS FITNESS FOR ANY PARTICULAR PURPOSE.
13*e72f3952SAlexander Dorokhine */
14*e72f3952SAlexander Dorokhine #include <stdarg.h>
15*e72f3952SAlexander Dorokhine #include <string.h>
16*e72f3952SAlexander Dorokhine #include "utf.h"
17*e72f3952SAlexander Dorokhine #include "utfdef.h"
18*e72f3952SAlexander Dorokhine
19*e72f3952SAlexander Dorokhine const
20*e72f3952SAlexander Dorokhine char*
utfrrune(const char * s,Rune c)21*e72f3952SAlexander Dorokhine utfrrune(const char *s, Rune c)
22*e72f3952SAlexander Dorokhine {
23*e72f3952SAlexander Dorokhine long c1;
24*e72f3952SAlexander Dorokhine Rune r;
25*e72f3952SAlexander Dorokhine const char *s1;
26*e72f3952SAlexander Dorokhine
27*e72f3952SAlexander Dorokhine if(c < Runesync) /* not part of utf sequence */
28*e72f3952SAlexander Dorokhine return strrchr(s, c);
29*e72f3952SAlexander Dorokhine
30*e72f3952SAlexander Dorokhine s1 = 0;
31*e72f3952SAlexander Dorokhine for(;;) {
32*e72f3952SAlexander Dorokhine c1 = *(uchar*)s;
33*e72f3952SAlexander Dorokhine if(c1 < Runeself) { /* one byte rune */
34*e72f3952SAlexander Dorokhine if(c1 == 0)
35*e72f3952SAlexander Dorokhine return s1;
36*e72f3952SAlexander Dorokhine if(c1 == c)
37*e72f3952SAlexander Dorokhine s1 = s;
38*e72f3952SAlexander Dorokhine s++;
39*e72f3952SAlexander Dorokhine continue;
40*e72f3952SAlexander Dorokhine }
41*e72f3952SAlexander Dorokhine c1 = chartorune(&r, s);
42*e72f3952SAlexander Dorokhine if(r == c)
43*e72f3952SAlexander Dorokhine s1 = s;
44*e72f3952SAlexander Dorokhine s += c1;
45*e72f3952SAlexander Dorokhine }
46*e72f3952SAlexander Dorokhine return 0;
47*e72f3952SAlexander Dorokhine }
48