1 /*
2 * Replacement for a missing asprintf and vasprintf.
3 *
4 * Provides the same functionality as the standard GNU library routines
5 * asprintf and vasprintf for those platforms that don't have them.
6 *
7 * The canonical version of this file is maintained in the rra-c-util package,
8 * which can be found at <https://www.eyrie.org/~eagle/software/rra-c-util/>.
9 *
10 * Written by Russ Allbery <eagle@eyrie.org>
11 * Copyright 2006, 2015 Russ Allbery <eagle@eyrie.org>
12 * Copyright 2008-2009, 2011, 2013
13 * The Board of Trustees of the Leland Stanford Junior University
14 *
15 * Copying and distribution of this file, with or without modification, are
16 * permitted in any medium without royalty provided the copyright notice and
17 * this notice are preserved. This file is offered as-is, without any
18 * warranty.
19 *
20 * SPDX-License-Identifier: FSFAP
21 */
22
23 #include <config.h>
24 #include <portable/macros.h>
25 #include <portable/system.h>
26
27 #include <errno.h>
28
29 /*
30 * If we're running the test suite, rename the functions to avoid conflicts
31 * with the system versions.
32 */
33 #if TESTING
34 # undef asprintf
35 # undef vasprintf
36 # define asprintf test_asprintf
37 # define vasprintf test_vasprintf
38 int test_asprintf(char **, const char *, ...)
39 __attribute__((__format__(printf, 2, 3)));
40 int test_vasprintf(char **, const char *, va_list)
41 __attribute__((__format__(printf, 2, 0)));
42 #endif
43
44
45 int
asprintf(char ** strp,const char * fmt,...)46 asprintf(char **strp, const char *fmt, ...)
47 {
48 va_list args;
49 int status;
50
51 va_start(args, fmt);
52 status = vasprintf(strp, fmt, args);
53 va_end(args);
54 return status;
55 }
56
57
58 int
vasprintf(char ** strp,const char * fmt,va_list args)59 vasprintf(char **strp, const char *fmt, va_list args)
60 {
61 va_list args_copy;
62 int status, needed, oerrno;
63
64 va_copy(args_copy, args);
65 needed = vsnprintf(NULL, 0, fmt, args_copy);
66 va_end(args_copy);
67 if (needed < 0) {
68 *strp = NULL;
69 return needed;
70 }
71 *strp = malloc(needed + 1);
72 if (*strp == NULL)
73 return -1;
74 status = vsnprintf(*strp, needed + 1, fmt, args);
75 if (status >= 0)
76 return status;
77 else {
78 oerrno = errno;
79 free(*strp);
80 *strp = NULL;
81 errno = oerrno;
82 return status;
83 }
84 }
85