glibc/stdio-common/errname.c

62 lines
1.7 KiB
C

/* Internal errno names mapping definition.
Copyright (C) 2022 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<https://www.gnu.org/licenses/>. */
#include <stdio.h>
#include <errno.h>
#include <libintl.h>
#include <array_length.h>
#ifndef ERR_MAP
# define ERR_MAP(n) n
#endif
static const union sys_errname_t
{
struct
{
#define MSGSTRFIELD1(line) str##line
#define MSGSTRFIELD(line) MSGSTRFIELD1(line)
#define _S(n, str) char MSGSTRFIELD(__LINE__)[sizeof(#n)];
#include <errlist.h>
#undef _S
};
char str[0];
} _sys_errname = { {
#define _S(n, s) #n,
#include <errlist.h>
#undef _S
} };
static const unsigned short _sys_errnameidx[] =
{
#define _S(n, s) \
[ERR_MAP(n)] = offsetof(union sys_errname_t, MSGSTRFIELD(__LINE__)),
#include <errlist.h>
#undef _S
};
const char *
__get_errname (int errnum)
{
int mapped = ERR_MAP (errnum);
if (mapped < 0 || mapped >= array_length (_sys_errnameidx)
|| (mapped > 0 && _sys_errnameidx[mapped] == 0))
return NULL;
return _sys_errname.str + _sys_errnameidx[mapped];
}