diff options
Diffstat (limited to 'io/ppoll.c')
| -rw-r--r-- | io/ppoll.c | 76 |
1 files changed, 76 insertions, 0 deletions
diff --git a/io/ppoll.c b/io/ppoll.c new file mode 100644 index 0000000000..a035cfeb1f --- /dev/null +++ b/io/ppoll.c @@ -0,0 +1,76 @@ +/* Copyright (C) 2006 Free Software Foundation, Inc. + This file is part of the GNU C Library. + Contributed by Ulrich Drepper <drepper@redhat.com>, 2006. + + 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 <limits.h> +#include <signal.h> +#include <stddef.h> /* For NULL. */ +#include <sys/poll.h> +#include <sysdep-cancel.h> + + +int +ppoll (struct pollfd *fds, nfds_t nfds, const struct timespec *timeout, + const sigset_t *sigmask) +{ + int tval = -1; + + /* poll uses a simple millisecond value. Convert it. */ + if (timeout != NULL) + { + if (timeout->tv_sec < 0 + || timeout->tv_nsec < 0 || timeout->tv_nsec >= 1000000000) + { + __set_errno (EINVAL); + return -1; + } + + if (timeout->tv_sec > INT_MAX / 1000 + || (timeout->tv_sec == INT_MAX / 1000 + && ((timeout->tv_nsec + 999999) / 1000000 > INT_MAX % 1000))) + /* We cannot represent the timeout in an int value. Wait + forever. */ + tval = -1; + else + tval = (timeout->tv_sec * 1000 + + (timeout->tv_nsec + 999999) / 1000000); + } + + /* The setting and restoring of the signal mask and the select call + should be an atomic operation. This can't be done without kernel + help. */ + sigset_t savemask; + if (sigmask != NULL) + __sigprocmask (SIG_SETMASK, sigmask, &savemask); + + /* Note the ppoll() is a cancellation point. But since we call + poll() which itself is a cancellation point we do not have + to do anything here. */ + int retval = __poll (fds, nfds, tval); + + if (sigmask != NULL) + __sigprocmask (SIG_SETMASK, &savemask, NULL); + + return retval; +} + +#ifndef ppoll +/* __poll handles cancellation. */ +LIBC_CANCEL_HANDLED (); +#endif |