xref: /inferno-os/lib9/sprint.c (revision 7ba4ff5becea2074955758024f3418d6ac79860f)
1 /*
2  * The authors of this software are Rob Pike and Ken Thompson.
3  *              Copyright (c) 2002 by Lucent Technologies.
4  * Permission to use, copy, modify, and distribute this software for any
5  * purpose without fee is hereby granted, provided that this entire notice
6  * is included in all copies of any software which is or includes a copy
7  * or modification of this software and in all copies of the supporting
8  * documentation for such software.
9  * THIS SOFTWARE IS BEING PROVIDED "AS IS", WITHOUT ANY EXPRESS OR IMPLIED
10  * WARRANTY.  IN PARTICULAR, NEITHER THE AUTHORS NOR LUCENT TECHNOLOGIES MAKE ANY
11  * REPRESENTATION OR WARRANTY OF ANY KIND CONCERNING THE MERCHANTABILITY
12  * OF THIS SOFTWARE OR ITS FITNESS FOR ANY PARTICULAR PURPOSE.
13  */
14 #include "lib9.h"
15 
16 int
sprint(char * buf,char * fmt,...)17 sprint(char *buf, char *fmt, ...)
18 {
19 	int n;
20 	uint len;
21 	va_list args;
22 
23 	len = 1<<30;  /* big number, but sprint is deprecated anyway */
24 	/*
25 	 * the stack might be near the top of memory, so
26 	 * we must be sure not to overflow a 32-bit pointer.
27 	 */
28 	if((uintptr)buf+len < (uintptr)buf)
29 		len = -(uint)buf-1;
30 
31 	va_start(args, fmt);
32 	n = vsnprint(buf, len, fmt, args);
33 	va_end(args);
34 	return n;
35 }
36