pci: Make host bridge TypeInfos const
[qemu-kvm.git] / event_notifier.c
blob2c207e1399b34901d058b7856efb682d485d8e23
1 /*
2 * event notifier support
4 * Copyright Red Hat, Inc. 2010
6 * Authors:
7 * Michael S. Tsirkin <mst@redhat.com>
9 * This work is licensed under the terms of the GNU GPL, version 2 or later.
10 * See the COPYING file in the top-level directory.
13 #include "qemu-common.h"
14 #include "event_notifier.h"
15 #include "qemu-char.h"
17 #ifdef CONFIG_EVENTFD
18 #include <sys/eventfd.h>
19 #endif
21 void event_notifier_init_fd(EventNotifier *e, int fd)
23 e->fd = fd;
26 int event_notifier_init(EventNotifier *e, int active)
28 #ifdef CONFIG_EVENTFD
29 int fd = eventfd(!!active, EFD_NONBLOCK | EFD_CLOEXEC);
30 if (fd < 0)
31 return -errno;
32 e->fd = fd;
33 return 0;
34 #else
35 return -ENOSYS;
36 #endif
39 void event_notifier_cleanup(EventNotifier *e)
41 close(e->fd);
44 int event_notifier_get_fd(EventNotifier *e)
46 return e->fd;
49 int event_notifier_set_handler(EventNotifier *e,
50 EventNotifierHandler *handler)
52 return qemu_set_fd_handler(e->fd, (IOHandler *)handler, NULL, e);
55 int event_notifier_set(EventNotifier *e)
57 uint64_t value = 1;
58 int r = write(e->fd, &value, sizeof(value));
59 return r == sizeof(value);
62 int event_notifier_test_and_clear(EventNotifier *e)
64 uint64_t value;
65 int r = read(e->fd, &value, sizeof(value));
66 return r == sizeof(value);