xref: /freebsd/sys/libkern/asprintf.c (revision e453e498cbb88570a3ff7b3679de65c88707da95)
1 /*-
2  * Copyright (c) 2013-2015 Sandvine Inc.  All rights reserved.
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  */
26 
27 #include <sys/param.h>
28 #include <sys/systm.h>
29 #include <sys/malloc.h>
30 #include <sys/stdarg.h>
31 
32 int
vasprintf(char ** buf,struct malloc_type * mtp,const char * format,va_list va)33 vasprintf(char **buf, struct malloc_type *mtp, const char *format, va_list va)
34 {
35 	int len, ret;
36 	va_list tmp_va;
37 	char dummy;
38 
39 	va_copy(tmp_va, va);
40 	len = vsnprintf(&dummy, 0, format, tmp_va);
41 	va_end(tmp_va);
42 	if (len < 0) {
43 		*buf = NULL;
44 		return (len);
45 	}
46 
47 	/* Account for null terminator. */
48 	len += 1;
49 	*buf = malloc(len, mtp, M_NOWAIT);
50 	if (*buf == NULL)
51 		return (-1);
52 
53 	ret = vsnprintf(*buf, len, format, va);
54 	if (ret < 0) {
55 		free(*buf, mtp);
56 		*buf = NULL;
57 	}
58 
59 	return (ret);
60 }
61 
62 int
asprintf(char ** buf,struct malloc_type * mtp,const char * format,...)63 asprintf(char **buf, struct malloc_type *mtp, const char *format, ...)
64 {
65 	int ret;
66 	va_list va;
67 
68 	va_start(va, format);
69 	ret = vasprintf(buf, mtp, format, va);
70 	va_end(va);
71 
72 	return (ret);
73 }
74