1 /*
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright © 2020 Keith Packard
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  *
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  *
13  * 2. Redistributions in binary form must reproduce the above
14  *    copyright notice, this list of conditions and the following
15  *    disclaimer in the documentation and/or other materials provided
16  *    with the distribution.
17  *
18  * 3. Neither the name of the copyright holder nor the names of its
19  *    contributors may be used to endorse or promote products derived
20  *    from this software without specific prior written permission.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
23  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
24  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
25  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
26  * COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
27  * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
28  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
29  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
31  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
32  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
33  * OF THE POSSIBILITY OF SUCH DAMAGE.
34  */
35 
36 #include <limits.h>
37 #include <stdarg.h>
38 #include <stdlib.h>
39 #include "stdio_private.h"
40 
41 int
vasprintf(char ** strp,const char * fmt,va_list ap)42 vasprintf(char **strp, const char *fmt, va_list ap)
43 {
44 	struct __file_str f = FDEV_SETUP_STRING_ALLOC();
45 	int i;
46 
47 	i = vfprintf(&f.file, fmt, ap);
48 	if (i >= 0) {
49                 char *buf = f.end - f.size;
50 		char *s = realloc(buf, i+1);
51 		if (s) {
52 			s[i] = 0;
53 			*strp = s;
54 		} else {
55 			free(buf);
56 			i = EOF;
57 		}
58 	}
59 	return i;
60 }
61