X-Git-Url: https://tinc-vpn.org/git/browse?p=tinc;a=blobdiff_plain;f=src%2Fevent.c;h=1283edd332b8334fa8fc78a6faedb03d2a397516;hp=84b18b3d3f5c31cde79acf75f49d48bf601850ed;hb=d6b45d005530496e48325a6174ecdd889a17bfc1;hpb=5ec513ec0ffc735e30c559a03378659ba4cc4515

diff --git a/src/event.c b/src/event.c
index 84b18b3d..1283edd3 100644
--- a/src/event.c
+++ b/src/event.c
@@ -1,6 +1,6 @@
 /*
     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
@@ -41,12 +41,15 @@ static int io_compare(const io_t *a, const io_t *b) {
 #ifndef HAVE_MINGW
 	return a->fd - b->fd;
 #else
+
 	if(a->event < b->event) {
 		return -1;
 	}
+
 	if(a->event > b->event) {
 		return 1;
 	}
+
 	return 0;
 #endif
 }
@@ -234,6 +237,8 @@ static void signal_handler(int signum) {
 }
 
 static void signalio_handler(void *data, int flags) {
+	(void)data;
+	(void)flags;
 	unsigned char signum;
 
 	if(read(pipefd[0], &signum, 1) != 1) {
@@ -345,6 +350,8 @@ bool event_loop(void) {
 			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);
@@ -357,10 +364,12 @@ bool event_loop(void) {
 			/*
 			   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;
+			}
 		}
 	}
 
@@ -369,7 +378,7 @@ bool event_loop(void) {
 	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);
@@ -386,71 +395,87 @@ bool event_loop(void) {
 		   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;
 		}
 	}