1 /***********************************************************************
2 * *
3 * This software is part of the ast package *
4 * Copyright (c) 1985-2010 AT&T Intellectual Property *
5 * and is licensed under the *
6 * Common Public License, Version 1.0 *
7 * by AT&T Intellectual Property *
8 * *
9 * A copy of the License is available at *
10 * http://www.opensource.org/licenses/cpl1.0.txt *
11 * (with md5 checksum 059e8cd6165cb4c31e351f2b69388fd9) *
12 * *
13 * Information and Software Systems Research *
14 * AT&T Research *
15 * Florham Park NJ *
16 * *
17 * Glenn Fowler <gsf@research.att.com> *
18 * David Korn <dgk@research.att.com> *
19 * Phong Vo <kpv@research.att.com> *
20 * *
21 ***********************************************************************/
22 #pragma prototyped
23
24 #include "stdhdr.h"
25
26 int
vsnprintf(char * s,int n,const char * fmt,va_list args)27 vsnprintf(char* s, int n, const char* fmt, va_list args)
28 {
29 Sfio_t f;
30 int v;
31
32 if (!s)
33 return -1;
34
35 /*
36 * make a fake stream
37 */
38
39 SFCLEAR(&f, NiL);
40 f.flags = SF_STRING|SF_WRITE;
41 f.bits = SF_PRIVATE;
42 f.mode = SF_WRITE;
43 f.size = n - 1;
44 f.data = f.next = f.endr = (uchar*)s;
45 f.endb = f.endw = f.data + f.size;
46
47 /*
48 * call and fix up
49 */
50
51 v = sfvprintf(&f, fmt, args);
52 *f.next = 0;
53 _Sfi = f.next - f.data;
54 return v;
55 }
56