Initial import from FreeBSD RELENG_4:
[dragonfly.git] / lib / libc / stdio / vsnprintf.c
CommitLineData
984263bc
MD
1/*-
2 * Copyright (c) 1990, 1993
3 * The Regents of the University of California. All rights reserved.
4 *
5 * This code is derived from software contributed to Berkeley by
6 * Chris Torek.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. All advertising materials mentioning features or use of this software
17 * must display the following acknowledgement:
18 * This product includes software developed by the University of
19 * California, Berkeley and its contributors.
20 * 4. Neither the name of the University nor the names of its contributors
21 * may be used to endorse or promote products derived from this software
22 * without specific prior written permission.
23 *
24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34 * SUCH DAMAGE.
35 */
36
37#if defined(LIBC_SCCS) && !defined(lint)
38#if 0
39static char sccsid[] = "@(#)vsnprintf.c 8.1 (Berkeley) 6/4/93";
40#endif
41static const char rcsid[] =
42 "$FreeBSD: src/lib/libc/stdio/vsnprintf.c,v 1.12.2.1 2002/09/23 06:58:17 maxim Exp $";
43#endif /* LIBC_SCCS and not lint */
44
45#include <limits.h>
46#include <stdio.h>
47
48int
49vsnprintf(str, n, fmt, ap)
50 char *str;
51 size_t n;
52 const char *fmt;
53 _BSD_VA_LIST_ ap;
54{
55 size_t on;
56 int ret;
57 char dummy;
58 FILE f;
59
60 on = n;
61 if (n != 0)
62 n--;
63 if (n > INT_MAX)
64 n = INT_MAX;
65 /* Stdio internals do not deal correctly with zero length buffer */
66 if (n == 0) {
67 str = &dummy;
68 n = 1;
69 }
70 f._file = -1;
71 f._flags = __SWR | __SSTR;
72 f._bf._base = f._p = (unsigned char *)str;
73 f._bf._size = f._w = n;
74 ret = vfprintf(&f, fmt, ap);
75 if (on > 0)
76 *f._p = '\0';
77 return (ret);
78}