tevent: let tevent_loop_once() just run one fd event

This makes the logic much simpler for the callers,
and matches the samba3 behavior.

If needed we can add performance tunning for tevent_loop_wait()
later.

metze

3 files changed, 7 insertions, 45 deletions

diff --git a/lib/tevent/tevent_epoll.c b/lib/tevent/tevent_epoll.c
index b63d299d94..38a14883cc 100644
--- a/lib/tevent/tevent_epoll.c
+++ b/lib/tevent/tevent_epoll.c
@@ -35,14 +35,6 @@ struct epoll_event_context {
 	/* a pointer back to the generic event_context */
 	struct tevent_context *ev;
 
-	/* this is changed by the destructors for the fd event
-	   type. It is used to detect event destruction by event
-	   handlers, which means the code that is calling the event
-	   handler needs to assume that the linked list is no longer
-	   valid
-	*/
-	uint32_t destruction_count;
-
 	/* when using epoll this is the handle from epoll_create */
 	int epoll_fd;
 
@@ -242,9 +234,8 @@ static void epoll_change_event(struct epoll_event_context *epoll_ev, struct teve
 static int epoll_event_loop(struct epoll_event_context *epoll_ev, struct timeval *tvalp)
 {
 	int ret, i;
-#define MAXEVENTS 32
+#define MAXEVENTS 1
 	struct epoll_event events[MAXEVENTS];
-	uint32_t destruction_count = ++epoll_ev->destruction_count;
 	int timeout = -1;
 
 	if (epoll_ev->epoll_fd == -1) return -1;
@@ -305,9 +296,7 @@ static int epoll_event_loop(struct epoll_event_context *epoll_ev, struct timeval
 		if (events[i].events & EPOLLOUT) flags |= TEVENT_FD_WRITE;
 		if (flags) {
 			fde->handler(epoll_ev->ev, fde, flags, fde->private_data);
-			if (destruction_count != epoll_ev->destruction_count) {
-				break;
-			}
+			break;
 		}
 	}
 
@@ -351,8 +340,6 @@ static int epoll_event_fd_destructor(struct tevent_fd *fde)
 
 		epoll_check_reopen(epoll_ev);
 
-		epoll_ev->destruction_count++;
-
 		epoll_del_event(epoll_ev, fde);
 	}
 
diff --git a/lib/tevent/tevent_select.c b/lib/tevent/tevent_select.c
index cdddb601c4..bbbb95fce8 100644
--- a/lib/tevent/tevent_select.c
+++ b/lib/tevent/tevent_select.c
@@ -38,10 +38,6 @@ struct select_event_context {
 
 	/* information for exiting from the event loop */
 	int exit_code;
-
-	/* this is incremented when the loop over events causes something which
-	   could change the events yet to be processed */
-	uint32_t destruction_count;
 };
 
 /*
@@ -95,8 +91,6 @@ static int select_event_fd_destructor(struct tevent_fd *fde)
 		if (select_ev->maxfd == fde->fd) {
 			select_ev->maxfd = EVENT_INVALID_MAXFD;
 		}
-
-		select_ev->destruction_count++;
 	}
 
 	return tevent_common_fd_destructor(fde);
@@ -138,7 +132,6 @@ static int select_event_loop_select(struct select_event_context *select_ev, stru
 	fd_set r_fds, w_fds;
 	struct tevent_fd *fde;
 	int selrtn;
-	uint32_t destruction_count = ++select_ev->destruction_count;
 
 	/* we maybe need to recalculate the maxfd */
 	if (select_ev->maxfd == EVENT_INVALID_MAXFD) {
@@ -200,15 +193,13 @@ static int select_event_loop_select(struct select_event_context *select_ev, stru
 			if (FD_ISSET(fde->fd, &w_fds)) flags |= TEVENT_FD_WRITE;
 			if (flags) {
 				fde->handler(select_ev->ev, fde, flags, fde->private_data);
-				if (destruction_count != select_ev->destruction_count) {
-					break;
-				}
+				break;
 			}
 		}
 	}
 
 	return 0;
-}		
+}
 
 /*
   do a single event loop using the events defined in ev 
diff --git a/lib/tevent/tevent_standard.c b/lib/tevent/tevent_standard.c
index 73a45e8c20..0ee99ca56b 100644
--- a/lib/tevent/tevent_standard.c
+++ b/lib/tevent/tevent_standard.c
@@ -48,14 +48,6 @@ struct std_event_context {
 	/* information for exiting from the event loop */
 	int exit_code;
 
-	/* this is changed by the destructors for the fd event
-	   type. It is used to detect event destruction by event
-	   handlers, which means the code that is calling the event
-	   handler needs to assume that the linked list is no longer
-	   valid
-	*/
-	uint32_t destruction_count;
-
 	/* when using epoll this is the handle from epoll_create */
 	int epoll_fd;
 
@@ -253,9 +245,8 @@ static void epoll_change_event(struct std_event_context *std_ev, struct tevent_f
 static int epoll_event_loop(struct std_event_context *std_ev, struct timeval *tvalp)
 {
 	int ret, i;
-#define MAXEVENTS 8
+#define MAXEVENTS 1
 	struct epoll_event events[MAXEVENTS];
-	uint32_t destruction_count = ++std_ev->destruction_count;
 	int timeout = -1;
 
 	if (std_ev->epoll_fd == -1) return -1;
@@ -316,9 +307,7 @@ static int epoll_event_loop(struct std_event_context *std_ev, struct timeval *tv
 		if (events[i].events & EPOLLOUT) flags |= TEVENT_FD_WRITE;
 		if (flags) {
 			fde->handler(std_ev->ev, fde, flags, fde->private_data);
-			if (destruction_count != std_ev->destruction_count) {
-				break;
-			}
+			break;
 		}
 	}
 
@@ -390,8 +379,6 @@ static int std_event_fd_destructor(struct tevent_fd *fde)
 			std_ev->maxfd = EVENT_INVALID_MAXFD;
 		}
 
-		std_ev->destruction_count++;
-
 		epoll_del_event(std_ev, fde);
 	}
 
@@ -459,7 +446,6 @@ static int std_event_loop_select(struct std_event_context *std_ev, struct timeva
 	fd_set r_fds, w_fds;
 	struct tevent_fd *fde;
 	int selrtn;
-	uint32_t destruction_count = ++std_ev->destruction_count;
 
 	/* we maybe need to recalculate the maxfd */
 	if (std_ev->maxfd == EVENT_INVALID_MAXFD) {
@@ -521,9 +507,7 @@ static int std_event_loop_select(struct std_event_context *std_ev, struct timeva
 			if (FD_ISSET(fde->fd, &w_fds)) flags |= TEVENT_FD_WRITE;
 			if (flags) {
 				fde->handler(std_ev->ev, fde, flags, fde->private_data);
-				if (destruction_count != std_ev->destruction_count) {
-					break;
-				}
+				break;
 			}
 		}
 	}