1 /**
2 * \file
3 */
4
5 #if defined(HAVE_EPOLL)
6
7 #include <sys/epoll.h>
8
9 #if defined(HOST_WIN32)
10 /* We assume that epoll is not available on windows */
11 #error
12 #endif
13
14 #define EPOLL_NEVENTS 128
15
16 static gint epoll_fd;
17 static struct epoll_event *epoll_events;
18
19 static gboolean
epoll_init(gint wakeup_pipe_fd)20 epoll_init (gint wakeup_pipe_fd)
21 {
22 struct epoll_event event;
23
24 #ifdef EPOOL_CLOEXEC
25 epoll_fd = epoll_create1 (EPOLL_CLOEXEC);
26 #else
27 epoll_fd = epoll_create (256);
28 fcntl (epoll_fd, F_SETFD, FD_CLOEXEC);
29 #endif
30
31 if (epoll_fd == -1) {
32 #ifdef EPOOL_CLOEXEC
33 g_error ("epoll_init: epoll (EPOLL_CLOEXEC) failed, error (%d) %s\n", errno, g_strerror (errno));
34 #else
35 g_error ("epoll_init: epoll (256) failed, error (%d) %s\n", errno, g_strerror (errno));
36 #endif
37 return FALSE;
38 }
39
40 event.events = EPOLLIN;
41 event.data.fd = wakeup_pipe_fd;
42 if (epoll_ctl (epoll_fd, EPOLL_CTL_ADD, event.data.fd, &event) == -1) {
43 g_error ("epoll_init: epoll_ctl () failed, error (%d) %s", errno, g_strerror (errno));
44 close (epoll_fd);
45 return FALSE;
46 }
47
48 epoll_events = g_new0 (struct epoll_event, EPOLL_NEVENTS);
49
50 return TRUE;
51 }
52
53 static void
epoll_register_fd(gint fd,gint events,gboolean is_new)54 epoll_register_fd (gint fd, gint events, gboolean is_new)
55 {
56 struct epoll_event event;
57
58 #ifndef EPOLLONESHOT
59 /* it was only defined on android in May 2013 */
60 #define EPOLLONESHOT 0x40000000
61 #endif
62
63 event.data.fd = fd;
64 event.events = EPOLLONESHOT;
65 if ((events & EVENT_IN) != 0)
66 event.events |= EPOLLIN;
67 if ((events & EVENT_OUT) != 0)
68 event.events |= EPOLLOUT;
69
70 if (epoll_ctl (epoll_fd, is_new ? EPOLL_CTL_ADD : EPOLL_CTL_MOD, event.data.fd, &event) == -1)
71 g_error ("epoll_register_fd: epoll_ctl(%s) failed, error (%d) %s", is_new ? "EPOLL_CTL_ADD" : "EPOLL_CTL_MOD", errno, g_strerror (errno));
72 }
73
74 static void
epoll_remove_fd(gint fd)75 epoll_remove_fd (gint fd)
76 {
77 if (epoll_ctl (epoll_fd, EPOLL_CTL_DEL, fd, NULL) == -1)
78 g_error ("epoll_remove_fd: epoll_ctl (EPOLL_CTL_DEL) failed, error (%d) %s", errno, g_strerror (errno));
79 }
80
81 static gint
epoll_event_wait(void (* callback)(gint fd,gint events,gpointer user_data),gpointer user_data)82 epoll_event_wait (void (*callback) (gint fd, gint events, gpointer user_data), gpointer user_data)
83 {
84 gint i, ready;
85
86 memset (epoll_events, 0, sizeof (struct epoll_event) * EPOLL_NEVENTS);
87
88 mono_gc_set_skip_thread (TRUE);
89
90 MONO_ENTER_GC_SAFE;
91 ready = epoll_wait (epoll_fd, epoll_events, EPOLL_NEVENTS, -1);
92 MONO_EXIT_GC_SAFE;
93
94 mono_gc_set_skip_thread (FALSE);
95
96 if (ready == -1) {
97 switch (errno) {
98 case EINTR:
99 ready = 0;
100 break;
101 default:
102 g_error ("epoll_event_wait: epoll_wait () failed, error (%d) %s", errno, g_strerror (errno));
103 break;
104 }
105 }
106
107 if (ready == -1)
108 return -1;
109
110 for (i = 0; i < ready; ++i) {
111 gint fd, events = 0;
112
113 fd = epoll_events [i].data.fd;
114 if (epoll_events [i].events & (EPOLLIN | EPOLLERR | EPOLLHUP))
115 events |= EVENT_IN;
116 if (epoll_events [i].events & (EPOLLOUT | EPOLLERR | EPOLLHUP))
117 events |= EVENT_OUT;
118
119 callback (fd, events, user_data);
120 }
121
122 return 0;
123 }
124
125 static ThreadPoolIOBackend backend_epoll = {
126 .init = epoll_init,
127 .register_fd = epoll_register_fd,
128 .remove_fd = epoll_remove_fd,
129 .event_wait = epoll_event_wait,
130 };
131
132 #endif
133