| /* Poll system call, with emulation if it is not available. |
| Copyright (C) 1997,1998,1999,2000,2001,2002,2006 |
| 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, write to the Free |
| Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA |
| 02111-1307 USA. */ |
| |
| #include <errno.h> |
| #include <sys/poll.h> |
| |
| #include <sysdep-cancel.h> |
| #include <sys/syscall.h> |
| #include <bp-checks.h> |
| |
| #include <kernel-features.h> |
| |
| #if defined __NR_poll || __ASSUME_POLL_SYSCALL > 0 |
| |
| # if __ASSUME_POLL_SYSCALL == 0 |
| static int __emulate_poll (struct pollfd *fds, nfds_t nfds, |
| int timeout) internal_function; |
| # endif |
| |
| |
| # if __ASSUME_POLL_SYSCALL == 0 |
| /* For loser kernels. */ |
| static int |
| loser_poll (struct pollfd *fds, nfds_t nfds, int timeout) |
| { |
| static int must_emulate; |
| |
| if (!must_emulate) |
| { |
| int errno_saved = errno; |
| int retval = INLINE_SYSCALL (poll, 3, CHECK_N (fds, nfds), nfds, |
| timeout); |
| |
| if (retval >= 0 || errno != ENOSYS) |
| return retval; |
| |
| __set_errno (errno_saved); |
| must_emulate = 1; |
| } |
| |
| return __emulate_poll (fds, nfds, timeout); |
| } |
| # endif |
| |
| |
| /* The real implementation. */ |
| int |
| __poll (fds, nfds, timeout) |
| struct pollfd *fds; |
| nfds_t nfds; |
| int timeout; |
| { |
| # if __ASSUME_POLL_SYSCALL == 0 |
| if (SINGLE_THREAD_P) |
| return loser_poll (CHECK_N (fds, nfds), nfds, timeout); |
| |
| int oldtype = LIBC_CANCEL_ASYNC (); |
| |
| int result = loser_poll (CHECK_N (fds, nfds), nfds, timeout); |
| |
| LIBC_CANCEL_RESET (oldtype); |
| |
| return result; |
| # else |
| if (SINGLE_THREAD_P) |
| return INLINE_SYSCALL (poll, 3, CHECK_N (fds, nfds), nfds, timeout); |
| |
| int oldtype = LIBC_CANCEL_ASYNC (); |
| |
| int result = INLINE_SYSCALL (poll, 3, CHECK_N (fds, nfds), nfds, timeout); |
| |
| LIBC_CANCEL_RESET (oldtype); |
| |
| return result; |
| # endif |
| } |
| libc_hidden_def (__poll) |
| weak_alias (__poll, poll) |
| strong_alias (__poll, __libc_poll) |
| |
| /* Get the emulation code. */ |
| # define __poll(fds, nfds, timeout) \ |
| static internal_function __emulate_poll (fds, nfds, timeout) |
| #endif |
| |
| #if __ASSUME_POLL_SYSCALL == 0 |
| # include <sysdeps/unix/bsd/poll.c> |
| #endif |