/*
event.c -- I/O, timeout and signal event handling
- Copyright (C) 2012-2013 Guus Sliepen <guus@tinc-vpn.org>
+ Copyright (C) 2012-2018 Guus Sliepen <guus@tinc-vpn.org>
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
}
static void signalio_handler(void *data, int flags) {
+ (void)data;
+ (void)flags;
unsigned char signum;
if(read(pipefd[0], &signum, 1) != 1) {
continue;
}
+ unsigned int curgen = io_tree.generation;
+
for splay_each(io_t, io, &io_tree) {
if(FD_ISSET(io->fd, &writable)) {
io->cb(io->data, IO_WRITE);
/*
There are scenarios in which the callback will remove another io_t from the tree
(e.g. closing a double connection). Since splay_each does not support that, we
- need to exit the loop now. That's okay, since any remaining events will get picked
- up by the next select() call.
+ need to exit the loop if that happens. That's okay, since any remaining events will
+ get picked up by the next select() call.
*/
- break;
+ if(curgen != io_tree.generation) {
+ break;
+ }
}
}
while(running) {
struct timeval diff;
struct timeval *tv = get_time_remaining(&diff);
- DWORD timeout_ms = tv ? (tv->tv_sec * 1000 + tv->tv_usec / 1000 + 1) : WSA_INFINITE;
+ DWORD timeout_ms = tv ? (DWORD)(tv->tv_sec * 1000 + tv->tv_usec / 1000 + 1) : WSA_INFINITE;
if(!event_count) {
Sleep(timeout_ms);
Note that technically FD_CLOSE has the same problem, but it's okay because user code does not rely on
this event being fired again if ignored.
*/
- io_t *writeable_io = NULL;
+ unsigned int curgen = io_tree.generation;
- for splay_each(io_t, io, &io_tree)
+ for splay_each(io_t, io, &io_tree) {
if(io->flags & IO_WRITE && send(io->fd, NULL, 0, 0) == 0) {
- writeable_io = io;
- break;
+ io->cb(io->data, IO_WRITE);
+
+ if(curgen != io_tree.generation) {
+ break;
+ }
}
+ }
- if(writeable_io) {
- writeable_io->cb(writeable_io->data, IO_WRITE);
- continue;
+ if(event_count > WSA_MAXIMUM_WAIT_EVENTS) {
+ WSASetLastError(WSA_INVALID_PARAMETER);
+ return(false);
}
- WSAEVENT *events = xmalloc(event_count * sizeof(*events));
+ WSAEVENT events[WSA_MAXIMUM_WAIT_EVENTS];
+ io_t *io_map[WSA_MAXIMUM_WAIT_EVENTS];
DWORD event_index = 0;
for splay_each(io_t, io, &io_tree) {
events[event_index] = io->event;
+ io_map[event_index] = io;
event_index++;
}
- DWORD result = WSAWaitForMultipleEvents(event_count, events, FALSE, timeout_ms, FALSE);
+ /*
+ * If the generation number changes due to event addition
+ * or removal by a callback we restart the loop.
+ */
+ curgen = io_tree.generation;
- WSAEVENT event;
+ for(DWORD event_offset = 0; event_offset < event_count;) {
+ DWORD result = WSAWaitForMultipleEvents(event_count - event_offset, &events[event_offset], FALSE, timeout_ms, FALSE);
- if(result >= WSA_WAIT_EVENT_0 && result < WSA_WAIT_EVENT_0 + event_count) {
- event = events[result - WSA_WAIT_EVENT_0];
- }
+ if(result == WSA_WAIT_TIMEOUT) {
+ break;
+ }
- free(events);
+ if(result >= event_count - event_offset) {
+ return(false);
+ }
- if(result == WSA_WAIT_TIMEOUT) {
- continue;
- }
+ /* Look up io in the map by index. */
+ event_index = result - event_offset;
+ io_t *io = io_map[event_index];
- if(result < WSA_WAIT_EVENT_0 || result >= WSA_WAIT_EVENT_0 + event_count) {
- return false;
- }
+ if(io->fd == -1) {
+ io->cb(io->data, 0);
- io_t *io = splay_search(&io_tree, &((io_t) {
- .event = event
- }));
+ if(curgen != io_tree.generation) {
+ break;
+ }
+ } else {
+ WSANETWORKEVENTS network_events;
- if(!io) {
- abort();
- }
+ if(WSAEnumNetworkEvents(io->fd, io->event, &network_events) != 0) {
+ return(false);
+ }
- if(io->fd == -1) {
- io->cb(io->data, 0);
- } else {
- WSANETWORKEVENTS network_events;
+ if(network_events.lNetworkEvents & READ_EVENTS) {
+ io->cb(io->data, IO_READ);
- if(WSAEnumNetworkEvents(io->fd, io->event, &network_events) != 0) {
- return false;
- }
+ if(curgen != io_tree.generation) {
+ break;
+ }
+ }
- if(network_events.lNetworkEvents & READ_EVENTS) {
- io->cb(io->data, IO_READ);
+ /*
+ The fd might be available for write too. However, if we already fired the read callback, that
+ callback might have deleted the io (e.g. through terminate_connection()), so we can't fire the
+ write callback here. Instead, we loop back and let the writable io loop above handle it.
+ */
}
- /*
- The fd might be available for write too. However, if we already fired the read callback, that
- callback might have deleted the io (e.g. through terminate_connection()), so we can't fire the
- write callback here. Instead, we loop back and let the writable io loop above handle it.
- */
+ /* Continue checking the rest of the events. */
+ event_offset = event_index + 1;
+
+ /* Just poll the next time through. */
+ timeout_ms = 0;
}
}
projects / tinc / blobdiff