xref: /dragonfly/lib/libc/stdio/vasprintf.c (revision 6e285212)
1 /*	$OpenBSD: vasprintf.c,v 1.4 1998/06/21 22:13:47 millert Exp $	*/
2 
3 /*
4  * Copyright (c) 1997 Todd C. Miller <Todd.Miller@courtesan.com>
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. The name of the author may not be used to endorse or promote products
16  *    derived from this software without specific prior written permission.
17  *
18  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
19  * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
20  * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL
21  * THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
22  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
23  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
24  * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
25  * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
26  * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
27  * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28  *
29  * $FreeBSD: src/lib/libc/stdio/vasprintf.c,v 1.11 1999/08/28 00:01:19 peter Exp $
30  * $DragonFly: src/lib/libc/stdio/vasprintf.c,v 1.2 2003/06/17 04:26:46 dillon Exp $
31  */
32 
33 #include <stdio.h>
34 #include <stdlib.h>
35 #include <errno.h>
36 
37 int
38 vasprintf(str, fmt, ap)
39 	char **str;
40 	const char *fmt;
41 	_BSD_VA_LIST_ ap;
42 {
43 	int ret;
44 	FILE f;
45 
46 	f._file = -1;
47 	f._flags = __SWR | __SSTR | __SALC;
48 	f._bf._base = f._p = (unsigned char *)malloc(128);
49 	if (f._bf._base == NULL) {
50 		*str = NULL;
51 		errno = ENOMEM;
52 		return (-1);
53 	}
54 	f._bf._size = f._w = 127;		/* Leave room for the NULL */
55 	ret = vfprintf(&f, fmt, ap);
56 	*f._p = '\0';
57 	f._bf._base = reallocf(f._bf._base, f._bf._size + 1);
58 	if (f._bf._base == NULL) {
59 		errno = ENOMEM;
60 		ret = -1;
61 	}
62 	*str = (char *)f._bf._base;
63 	return (ret);
64 }
65