sysdeps/unix/sysv/linux/poll.c

   1 /* Poll system call.
   2    Copyright (C) 1997-2012 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    <http://www.gnu.org/licenses/>.  */
  18
  19 #include <errno.h>
  20 #include <sys/poll.h>
  21
  22 #include <sysdep-cancel.h>
  23 #include <sys/syscall.h>
  24 #include <bp-checks.h>
  25
  26 #include <kernel-features.h>
  27
  28 int
  29 __poll (fds, nfds, timeout)
  30      struct pollfd *fds;
  31      nfds_t nfds;
  32      int timeout;
  33 {
  34   if (SINGLE_THREAD_P)
  35     return INLINE_SYSCALL (poll, 3, CHECK_N (fds, nfds), nfds, timeout);
  36
  37   int oldtype = LIBC_CANCEL_ASYNC ();
  38
  39   int result = INLINE_SYSCALL (poll, 3, CHECK_N (fds, nfds), nfds, timeout);
  40
  41    LIBC_CANCEL_RESET (oldtype);
  42
  43   return result;
  44 }
  45 libc_hidden_def (__poll)
  46 weak_alias (__poll, poll)
  47 strong_alias (__poll, __libc_poll)