gmain: Fall back to pipes if kernel doesn't support EFD_CLOEXEC for eventfd()

Also remove the caching of checking for eventfd; just try it every time, it's
cheap enough to do so.

https://bugzilla.gnome.org/show_bug.cgi?id=653570
This commit is contained in:
Colin Walters 2011-06-28 10:03:15 -04:00
parent 8b1a0764f9
commit 1b0e5e7683

View File

@ -400,14 +400,6 @@ static GSList *main_contexts_without_pipe = NULL;
#ifndef G_OS_WIN32
#ifdef HAVE_EVENTFD
typedef struct {
guint checked_eventfd : 1;
guint have_eventfd : 1;
} EventFdState;
EventFdState event_fd_state = { 0, 0 };
#endif
/* The UNIX signal pipe contains a single byte specifying which
* signal was received.
*/
@ -570,26 +562,22 @@ g_main_context_init_pipe (GMainContext *context)
return;
#ifdef HAVE_EVENTFD
if (!event_fd_state.checked_eventfd
|| event_fd_state.have_eventfd)
{
int efd;
{
int efd;
event_fd_state.checked_eventfd = TRUE;
efd = eventfd (0, EFD_CLOEXEC);
if (efd == -1 && errno == ENOSYS)
{
event_fd_state.have_eventfd = FALSE;
if (!g_unix_open_pipe (context->wake_up_pipe, FD_CLOEXEC, &error))
g_error ("Cannot create pipe main loop wake-up: %s", error->message);
}
else if (efd >= 0)
{
event_fd_state.have_eventfd = TRUE;
context->wake_up_pipe[0] = efd;
}
else
g_error ("Cannot create eventfd for main loop wake-up: %s", g_strerror (errno));
efd = eventfd (0, EFD_CLOEXEC);
/* Fall through on -EINVAL too in case kernel doesn't know EFD_CLOEXEC. Bug #653570 */
if (efd == -1 && (errno == ENOSYS || errno == EINVAL))
{
if (!g_unix_open_pipe (context->wake_up_pipe, FD_CLOEXEC, &error))
g_error ("Cannot create pipe main loop wake-up: %s", error->message);
}
else if (efd >= 0)
{
context->wake_up_pipe[0] = efd;
}
else
g_error ("Cannot create eventfd for main loop wake-up: %s", g_strerror (errno));
}
#else
if (!g_unix_open_pipe (context->wake_up_pipe, FD_CLOEXEC, &error))
@ -2982,7 +2970,7 @@ g_main_context_check (GMainContext *context,
{
#ifndef G_OS_WIN32
#ifdef HAVE_EVENTFD
if (event_fd_state.have_eventfd)
if (context->wake_up_pipe[1] == -1)
{
guint64 buf;
read (context->wake_up_pipe[0], &buf, sizeof(guint64));
@ -3844,7 +3832,7 @@ g_main_context_wakeup_unlocked (GMainContext *context)
context->poll_waiting = FALSE;
#ifndef G_OS_WIN32
#ifdef HAVE_EVENTFD
if (event_fd_state.have_eventfd)
if (context->wake_up_pipe[1] == -1)
{
guint64 buf = 1;
write (context->wake_up_pipe[0], &buf, sizeof(buf));