glibc/misc/bits/select2.h
2012-02-09 23:18:22 +00:00

35 lines
1.4 KiB
C

/* Checking macros for select functions.
Copyright (C) 2011 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
<http://www.gnu.org/licenses/>. */
#ifndef _SYS_SELECT_H
# error "Never include <bits/select2.h> directly; use <sys/select.h> instead."
#endif
/* Helper functions to issue warnings and errors when needed. */
extern unsigned long int __fdelt_chk (unsigned long int __d);
extern unsigned long int __fdelt_warn (unsigned long int __d)
__warnattr ("bit outside of fd_set selected");
#undef __FD_ELT
#define __FD_ELT(d) \
__extension__ \
({ unsigned long int __d = (d); \
(__builtin_constant_p (__d) \
? (__d >= __FD_SETSIZE \
? __fdelt_warn (__d) : (__d / __NFDBITS)) \
: __fdelt_chk (__d)); })