1 /* Internal errno names mapping definition.
2 Copyright (C) 2022 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
4
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License as published by the Free Software Foundation; either
8 version 2.1 of the License, or (at your option) any later version.
9
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Lesser General Public License for more details.
14
15 You should have received a copy of the GNU Lesser General Public
16 License along with the GNU C Library; if not, see
17 <https://www.gnu.org/licenses/>. */
18
19 #include <stdio.h>
20 #include <errno.h>
21 #include <libintl.h>
22 #include <array_length.h>
23
24 #ifndef ERR_MAP
25 # define ERR_MAP(n) n
26 #endif
27
28 static const union sys_errname_t
29 {
30 struct
31 {
32 #define MSGSTRFIELD1(line) str##line
33 #define MSGSTRFIELD(line) MSGSTRFIELD1(line)
34 #define _S(n, str) char MSGSTRFIELD(__LINE__)[sizeof(#n)];
35 #include <errlist.h>
36 #undef _S
37 };
38 char str[0];
39 } _sys_errname = { {
40 #define _S(n, s) #n,
41 #include <errlist.h>
42 #undef _S
43 } };
44
45 static const unsigned short _sys_errnameidx[] =
46 {
47 #define _S(n, s) \
48 [ERR_MAP(n)] = offsetof(union sys_errname_t, MSGSTRFIELD(__LINE__)),
49 #include <errlist.h>
50 #undef _S
51 };
52
53 const char *
__get_errname(int errnum)54 __get_errname (int errnum)
55 {
56 int mapped = ERR_MAP (errnum);
57 if (mapped < 0 || mapped >= array_length (_sys_errnameidx)
58 || (mapped > 0 && _sys_errnameidx[mapped] == 0))
59 return NULL;
60 return _sys_errname.str + _sys_errnameidx[mapped];
61 }
62