xref: /plan9/sys/src/ape/lib/utf/utfecpy.c (revision 593dc095aefb2a85c828727bbfa9da139a49bdf4)
1*40ef9009SDavid du Colombier /*
2*40ef9009SDavid du Colombier  * The authors of this software are Rob Pike and Ken Thompson.
3*40ef9009SDavid du Colombier  *              Copyright (c) 2002 by Lucent Technologies.
4*40ef9009SDavid du Colombier  * Permission to use, copy, modify, and distribute this software for any
5*40ef9009SDavid du Colombier  * purpose without fee is hereby granted, provided that this entire notice
6*40ef9009SDavid du Colombier  * is included in all copies of any software which is or includes a copy
7*40ef9009SDavid du Colombier  * or modification of this software and in all copies of the supporting
8*40ef9009SDavid du Colombier  * documentation for such software.
9*40ef9009SDavid du Colombier  * THIS SOFTWARE IS BEING PROVIDED "AS IS", WITHOUT ANY EXPRESS OR IMPLIED
10*40ef9009SDavid du Colombier  * WARRANTY.  IN PARTICULAR, NEITHER THE AUTHORS NOR LUCENT TECHNOLOGIES MAKE ANY
11*40ef9009SDavid du Colombier  * REPRESENTATION OR WARRANTY OF ANY KIND CONCERNING THE MERCHANTABILITY
12*40ef9009SDavid du Colombier  * OF THIS SOFTWARE OR ITS FITNESS FOR ANY PARTICULAR PURPOSE.
13*40ef9009SDavid du Colombier  */
14*40ef9009SDavid du Colombier #include <stdarg.h>
15*40ef9009SDavid du Colombier #include <string.h>
16*40ef9009SDavid du Colombier #include "utf.h"
17*40ef9009SDavid du Colombier #include "utfdef.h"
18*40ef9009SDavid du Colombier 
19*40ef9009SDavid du Colombier char*
utfecpy(char * to,char * e,char * from)20*40ef9009SDavid du Colombier utfecpy(char *to, char *e, char *from)
21*40ef9009SDavid du Colombier {
22*40ef9009SDavid du Colombier 	char *end;
23*40ef9009SDavid du Colombier 
24*40ef9009SDavid du Colombier 	if(to >= e)
25*40ef9009SDavid du Colombier 		return to;
26*40ef9009SDavid du Colombier 	end = memccpy(to, from, '\0', e - to);
27*40ef9009SDavid du Colombier 	if(end == nil){
28*40ef9009SDavid du Colombier 		end = e-1;
29*40ef9009SDavid du Colombier 		while(end>to && (*--end&0xC0)==0x80)
30*40ef9009SDavid du Colombier 			;
31*40ef9009SDavid du Colombier 		*end = '\0';
32*40ef9009SDavid du Colombier 	}else{
33*40ef9009SDavid du Colombier 		end--;
34*40ef9009SDavid du Colombier 	}
35*40ef9009SDavid du Colombier 	return end;
36*40ef9009SDavid du Colombier }
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