1 /***********************************************************************
2 *                                                                      *
3 *               This software is part of the ast package               *
4 *          Copyright (c) 1985-2011 AT&T Intellectual Property          *
5 *                      and is licensed under the                       *
6 *                 Eclipse Public License, Version 1.0                  *
7 *                    by AT&T Intellectual Property                     *
8 *                                                                      *
9 *                A copy of the License is available at                 *
10 *          http://www.eclipse.org/org/documents/epl-v10.html           *
11 *         (with md5 checksum b35adb5213ca9657e911e9befb180842)         *
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 * form,va_list args)27 vsnprintf(char* s, int n, const char* form, va_list args)
28 {
29 	Sfio_t*	f;
30 	ssize_t	rv;
31 
32 	/* make a temp stream */
33 	if(!(f = sfnew(NIL(Sfio_t*),NIL(char*),(size_t)SF_UNBOUND,
34                         -1,SF_WRITE|SF_STRING)) )
35 		return -1;
36 
37 	if((rv = sfvprintf(f,form,args)) >= 0 )
38 	{	if(s && n > 0)
39 		{	if((rv+1) >= n)
40 				n--;
41 			else
42 				n = rv;
43 			memcpy(s, f->data, n);
44 			s[n] = 0;
45 		}
46 		_Sfi = rv;
47 	}
48 
49 	sfclose(f);
50 
51 	return rv;
52 }
53