1/* Copyright (C) 1991-2018 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
3
4 The GNU C Library is free software; you can redistribute it and/or
5 modify it under the terms of the GNU Lesser General Public
6 License as published by the Free Software Foundation; either
7 version 2.1 of the License, or (at your option) any later version.
8
9 The GNU C Library is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 Lesser General Public License for more details.
13
14 You should have received a copy of the GNU Lesser General Public
15 License along with the GNU C Library; if not, see
16 <http://www.gnu.org/licenses/>. */
17
18#include <assert.h>
19#include <errno.h>
20#include <stdio.h>
21#include <string.h>
22#include <sys/param.h>
23
24
25/* Fill buf with a string describing the errno code in ERRNUM. */
26int
27__xpg_strerror_r (int errnum, char *buf, size_t buflen)
28{
29 const char *estr = __strerror_r (errnum, buf, buflen);
30
31 /* We know that __strerror_r returns buf (with a dynamically computed
32 string) if errnum is invalid, otherwise it returns a string whose
33 storage has indefinite extent. */
34 if (estr == buf)
35 {
36 assert (errnum < 0 || errnum >= _sys_nerr_internal
37 || _sys_errlist_internal[errnum] == NULL);
38 return EINVAL;
39 }
40 else
41 {
42 assert (errnum >= 0 && errnum < _sys_nerr_internal
43 && _sys_errlist_internal[errnum] != NULL);
44
45 size_t estrlen = strlen (estr);
46
47 /* Terminate the string in any case. */
48 if (buflen > 0)
49 *((char *) __mempcpy (buf, estr, MIN (buflen - 1, estrlen))) = '\0';
50
51 return buflen <= estrlen ? ERANGE : 0;
52 }
53}
54