1 /*
2 * Copyright (c) 2004 Darren Tucker.
3 *
4 * Based originally on asprintf.c from OpenBSD:
5 * Copyright (c) 1997 Todd C. Miller <Todd.Miller@courtesan.com>
6 *
7 * Permission to use, copy, modify, and distribute this software for any
8 * purpose with or without fee is hereby granted, provided that the above
9 * copyright notice and this permission notice appear in all copies.
10 *
11 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
12 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
13 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
14 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
15 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
16 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
17 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
18 */
19
20 #include "openbsd-compat.h"
21
22 #ifndef HAVE_ASPRINTF
23
24 #include <errno.h>
25 #include <limits.h> /* for INT_MAX */
26 #include <stdarg.h>
27 #include <stdio.h> /* for vsnprintf */
28 #include <stdlib.h>
29
30 #define VA_COPY(dest, src) va_copy(dest, src)
31
32 #define INIT_SZ 128
33
34 int
vasprintf(char ** str,const char * fmt,va_list ap)35 vasprintf(char **str, const char *fmt, va_list ap)
36 {
37 int ret;
38 va_list ap2;
39 char *string, *newstr;
40 size_t len;
41
42 if ((string = malloc(INIT_SZ)) == NULL)
43 goto fail;
44
45 VA_COPY(ap2, ap);
46 ret = vsnprintf(string, INIT_SZ, fmt, ap2);
47 va_end(ap2);
48 if (ret >= 0 && ret < INIT_SZ) { /* succeeded with initial alloc */
49 *str = string;
50 } else if (ret == INT_MAX || ret < 0) { /* Bad length */
51 free(string);
52 goto fail;
53 } else { /* bigger than initial, realloc allowing for nul */
54 len = (size_t)ret + 1;
55 if ((newstr = realloc(string, len)) == NULL) {
56 free(string);
57 goto fail;
58 }
59 VA_COPY(ap2, ap);
60 ret = vsnprintf(newstr, len, fmt, ap2);
61 va_end(ap2);
62 if (ret < 0 || (size_t)ret >= len) { /* failed with realloc'ed string */
63 free(newstr);
64 goto fail;
65 }
66 *str = newstr;
67 }
68 return (ret);
69
70 fail:
71 *str = NULL;
72 errno = ENOMEM;
73 return (-1);
74 }
75
asprintf(char ** str,const char * fmt,...)76 int asprintf(char **str, const char *fmt, ...)
77 {
78 va_list ap;
79 int ret;
80
81 *str = NULL;
82 va_start(ap, fmt);
83 ret = vasprintf(str, fmt, ap);
84 va_end(ap);
85
86 return ret;
87 }
88 #endif
89