/*
change the epoll event to the given fd_event
*/
static void epoll_mod_event(struct epoll_event_context *epoll_ev, struct tevent_fd *fde)
{
struct epoll_event event;
if (epoll_ev->epoll_fd == -1) return;
fde->additional_flags &= ~EPOLL_ADDITIONAL_FD_FLAG_REPORT_ERROR;
ZERO_STRUCT(event);
event.events = epoll_map_flags(fde->flags);
event.data.ptr = fde;
if (epoll_ctl(epoll_ev->epoll_fd, EPOLL_CTL_MOD, fde->fd, &event) != 0) {
epoll_panic(epoll_ev, "EPOLL_CTL_MOD failed");
}
/* only if we want to read we want to tell the event handler about errors */
if (fde->flags & TEVENT_FD_READ) {
fde->additional_flags |= EPOLL_ADDITIONAL_FD_FLAG_REPORT_ERROR;
}
}
/*
reopen the epoll handle when our pid changes
see http://junkcode.samba.org/ftp/unpacked/junkcode/epoll_fork.c for an
demonstration of why this is needed
*/
static void epoll_check_reopen(struct epoll_event_context *epoll_ev)
{
struct tevent_fd *fde;
bool *caller_panic_state = epoll_ev->panic_state;
bool panic_triggered = false;
if (epoll_ev->pid == getpid()) {
return;
}
close(epoll_ev->epoll_fd);
epoll_ev->epoll_fd = epoll_create(64);
if (epoll_ev->epoll_fd == -1) {
epoll_panic(epoll_ev, "epoll_create() failed", false);
return;
}
if (!ev_set_close_on_exec(epoll_ev->epoll_fd)) {
tevent_debug(epoll_ev->ev, TEVENT_DEBUG_WARNING,
"Failed to set close-on-exec, file descriptor may be leaked to children.\n");
}
epoll_ev->pid = getpid();
epoll_ev->panic_state = &panic_triggered;
for (fde=epoll_ev->ev->fd_events;fde;fde=fde->next) {
fde->additional_flags &= ~EPOLL_ADDITIONAL_FD_FLAG_HAS_EVENT;
epoll_update_event(epoll_ev, fde);
if (panic_triggered) {
if (caller_panic_state != NULL) {
*caller_panic_state = true;
}
return;
}
}
epoll_ev->panic_state = NULL;
}
/*
event loop handling using epoll
*/
static int epoll_event_loop(struct epoll_event_context *epoll_ev, struct timeval *tvalp)
{
int ret, i;
#define MAXEVENTS 1
struct epoll_event events[MAXEVENTS];
int timeout = -1;
if (epoll_ev->epoll_fd == -1) return -1;
if (tvalp) {
/* it's better to trigger timed events a bit later than to early */
timeout = ((tvalp->tv_usec+999) / 1000) + (tvalp->tv_sec*1000);
}
if (epoll_ev->ev->signal_events &&
tevent_common_check_signal(epoll_ev->ev)) {
return 0;
}
ret = epoll_wait(epoll_ev->epoll_fd, events, MAXEVENTS, timeout);
if (ret == -1 && errno == EINTR && epoll_ev->ev->signal_events) {
if (tevent_common_check_signal(epoll_ev->ev)) {
return 0;
}
}
if (ret == -1 && errno != EINTR) {
epoll_panic(epoll_ev, "epoll_wait() failed");
return -1;
}
if (ret == 0 && tvalp) {
/* we don't care about a possible delay here */
tevent_common_loop_timer_delay(epoll_ev->ev);
return 0;
}
for (i=0;i<ret;i++) {
struct tevent_fd *fde = talloc_get_type(events[i].data.ptr,
struct tevent_fd);
uint16_t flags = 0;
if (fde == NULL) {
epoll_panic(epoll_ev, "epoll_wait() gave bad data");
return -1;
}
if (events[i].events & (EPOLLHUP|EPOLLERR)) {
fde->additional_flags |= EPOLL_ADDITIONAL_FD_FLAG_GOT_ERROR;
/*
* if we only wait for TEVENT_FD_WRITE, we should not tell the
* event handler about it, and remove the epoll_event,
* as we only report errors when waiting for read events,
* to match the select() behavior
*/
if (!(fde->additional_flags & EPOLL_ADDITIONAL_FD_FLAG_REPORT_ERROR)) {
epoll_del_event(epoll_ev, fde);
continue;
}
flags |= TEVENT_FD_READ;
}
if (events[i].events & EPOLLIN) flags |= TEVENT_FD_READ;
if (events[i].events & EPOLLOUT) flags |= TEVENT_FD_WRITE;
if (flags) {
fde->handler(epoll_ev->ev, fde, flags, fde->private_data);
break;
}
}
return 0;
}