1 /* Poll system call, with emulation if it is not available.
2 Copyright (C) 1997,1998,1999,2000,2001,2002 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
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.
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.
15 You should have received a copy of the GNU Lesser General Public
16 License along with the GNU C Library; if not, write to the Free
17 Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
23 #include <sysdep-cancel.h>
24 #include <sys/syscall.h>
25 #include <bp-checks.h>
27 #include "kernel-features.h"
29 #if defined __NR_poll || __ASSUME_POLL_SYSCALL > 0
31 # if __ASSUME_POLL_SYSCALL == 0
32 static int __emulate_poll (struct pollfd
*fds
, nfds_t nfds
,
33 int timeout
) internal_function
;
37 # if __ASSUME_POLL_SYSCALL == 0
38 /* For loser kernels. */
40 loser_poll (struct pollfd
*fds
, nfds_t nfds
, int timeout
)
42 static int must_emulate
;
46 int errno_saved
= errno
;
47 int retval
= INLINE_SYSCALL (poll
, 3, CHECK_N (fds
, nfds
), nfds
,
50 if (retval
>= 0 || errno
!= ENOSYS
)
53 __set_errno (errno_saved
);
57 return __emulate_poll (fds
, nfds
, timeout
);
62 /* The real implementation. */
64 __poll (fds
, nfds
, timeout
)
69 # if __ASSUME_POLL_SYSCALL == 0
71 return loser_poll (CHECK_N (fds
, nfds
), nfds
, timeout
);
73 int oldtype
= LIBC_CANCEL_ASYNC ();
75 int result
= loser_poll (CHECK_N (fds
, nfds
), nfds
, timeout
);
77 LIBC_CANCEL_RESET (oldtype
);
82 return INLINE_SYSCALL (poll
, 3, CHECK_N (fds
, nfds
), nfds
, timeout
);
84 int oldtype
= LIBC_CANCEL_ASYNC ();
86 int result
= INLINE_SYSCALL (poll
, 3, CHECK_N (fds
, nfds
), nfds
, timeout
);
88 LIBC_CANCEL_RESET (oldtype
);
93 libc_hidden_def (__poll
)
94 weak_alias (__poll
, poll
)
95 strong_alias (__poll
, __libc_poll
)
97 /* Get the emulation code. */
98 # define __poll(fds, nfds, timeout) \
99 static internal_function __emulate_poll (fds, nfds, timeout)
102 #if __ASSUME_POLL_SYSCALL == 0
103 # include <sysdeps/unix/bsd/poll.c>