| /* |
| Copyright (c) 2012-2013 Martin Sustrik All rights reserved. |
| Copyright 2015 Garrett D'Amore <garrett@damore.org> |
| |
| Permission is hereby granted, free of charge, to any person obtaining a copy |
| of this software and associated documentation files (the "Software"), |
| to deal in the Software without restriction, including without limitation |
| the rights to use, copy, modify, merge, publish, distribute, sublicense, |
| and/or sell copies of the Software, and to permit persons to whom |
| the Software is furnished to do so, subject to the following conditions: |
| |
| The above copyright notice and this permission notice shall be included |
| in all copies or substantial portions of the Software. |
| |
| THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
| IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
| FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL |
| THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER |
| LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING |
| FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS |
| IN THE SOFTWARE. |
| */ |
| |
| #include "err.h" |
| #include "closefd.h" |
| |
| #include <sys/eventfd.h> |
| #include <unistd.h> |
| #include <fcntl.h> |
| #include <stdint.h> |
| |
| int nn_efd_init (struct nn_efd *self) |
| { |
| int rc; |
| int flags; |
| |
| self->efd = eventfd (0, EFD_CLOEXEC); |
| if (self->efd == -1 && (errno == EMFILE || errno == ENFILE)) |
| return -EMFILE; |
| errno_assert (self->efd != -1); |
| |
| flags = fcntl (self->efd, F_GETFL, 0); |
| if (flags == -1) |
| flags = 0; |
| rc = fcntl (self->efd, F_SETFL, flags | O_NONBLOCK); |
| errno_assert (rc != -1); |
| |
| return 0; |
| } |
| |
| void nn_efd_term (struct nn_efd *self) |
| { |
| int fd = self->efd; |
| self->efd = -1; |
| nn_closefd (fd); |
| } |
| |
| void nn_efd_stop (struct nn_efd *self) |
| { |
| nn_efd_signal (self); |
| } |
| |
| nn_fd nn_efd_getfd (struct nn_efd *self) |
| { |
| return self->efd; |
| } |
| |
| void nn_efd_signal (struct nn_efd *self) |
| { |
| const uint64_t one = 1; |
| ssize_t nbytes; |
| int fd = self->efd; |
| |
| if (nn_slow (fd < 0)) |
| return; |
| |
| nbytes = write (fd, &one, sizeof (one)); |
| errno_assert (nbytes == sizeof (one)); |
| } |
| |
| void nn_efd_unsignal (struct nn_efd *self) |
| { |
| uint64_t count; |
| int fd = self->efd; |
| |
| if (nn_slow (fd < 0)) |
| return; |
| |
| /* Extract all the signals from the eventfd. */ |
| ssize_t sz = read (fd, &count, sizeof (count)); |
| errno_assert (sz >= 0); |
| nn_assert (sz == sizeof (count)); |
| } |