1 /*
2 * The authors of this software are Rob Pike and Ken Thompson,
3 * with contributions from Mike Burrows and Sean Dorward.
4 *
5 * Copyright (c) 2002-2006 by Lucent Technologies.
6 * Portions Copyright (c) 2004 Google Inc.
7 *
8 * Permission to use, copy, modify, and distribute this software for any
9 * purpose without fee is hereby granted, provided that this entire notice
10 * is included in all copies of any software which is or includes a copy
11 * or modification of this software and in all copies of the supporting
12 * documentation for such software.
13 * THIS SOFTWARE IS BEING PROVIDED "AS IS", WITHOUT ANY EXPRESS OR IMPLIED
14 * WARRANTY. IN PARTICULAR, NEITHER THE AUTHORS NOR LUCENT TECHNOLOGIES
15 * NOR GOOGLE INC MAKE ANY REPRESENTATION OR WARRANTY OF ANY KIND CONCERNING
16 * THE MERCHANTABILITY OF THIS SOFTWARE OR ITS FITNESS FOR ANY PARTICULAR PURPOSE.
17 */
18
19 #include <u.h>
20 #include <libc.h>
21 #include "fmtdef.h"
22
23 int
24 sprint(char *buf, char *fmt, ...)
25 {
26 int n;
27 uint len;
28 va_list args;
29
30 len = 1<<30; /* big number, but sprint is deprecated anyway */
31 /*
32 * on PowerPC, the stack is near the top of memory, so
33 * we must be sure not to overflow a 32-bit pointer.
34 *
35 * careful! gcc-4.2 assumes buf+len < buf can never be true and
36 * optimizes the test away. casting to uintptr works around this bug.
37 */
38 if((uintptr)buf+len < (uintptr)buf)
39 len = -(uintptr)buf-1;
40
41 va_start(args, fmt);
42 n = vsnprint(buf, len, fmt, args);
43 va_end(args);
44 return n;
45 }