tevent: add tevent_loop_set_nesting_hook()

This is an ugly hack to let the s4 server work arround
some bugs related to nested events and uid changing.

metze

3 files changed, 50 insertions, 1 deletions

diff --git a/lib/tevent/tevent.c b/lib/tevent/tevent.c
index a6bac6097d7..e9b6b7d0558 100644
--- a/lib/tevent/tevent.c
+++ b/lib/tevent/tevent.c
@@ -374,6 +374,14 @@ void tevent_loop_allow_nesting(struct tevent_context *ev)
 	ev->nesting.allowed = true;
 }
 
+void tevent_loop_set_nesting_hook(struct tevent_context *ev,
+				  tevent_nesting_hook hook,
+				  void *private_data)
+{
+	ev->nesting.hook_fn = hook;
+	ev->nesting.hook_private = private_data;
+}
+
 static void tevent_abort_nesting(struct tevent_context *ev, const char *location)
 {
 	const char *reason;
@@ -393,6 +401,7 @@ static void tevent_abort_nesting(struct tevent_context *ev, const char *location
 int _tevent_loop_once(struct tevent_context *ev, const char *location)
 {
 	int ret;
+	void *nesting_stack_ptr = NULL;
 
 	ev->nesting.level++;
 
@@ -402,12 +411,41 @@ int _tevent_loop_once(struct tevent_context *ev, const char *location)
 			errno = ELOOP;
 			return -1;
 		}
+		if (ev->nesting.hook_fn) {
+			int ret2;
+			ret2 = ev->nesting.hook_fn(ev,
+						   ev->nesting.hook_private,
+						   ev->nesting.level,
+						   true,
+						   (void *)&nesting_stack_ptr,
+						   location);
+			if (ret2 != 0) {
+				ret = ret2;
+				goto done;
+			}
+		}
 	}
 
 	ret = ev->ops->loop_once(ev, location);
 
-	ev->nesting.level--;
+	if (ev->nesting.level > 1) {
+		if (ev->nesting.hook_fn) {
+			int ret2;
+			ret2 = ev->nesting.hook_fn(ev,
+						   ev->nesting.hook_private,
+						   ev->nesting.level,
+						   false,
+						   (void *)&nesting_stack_ptr,
+						   location);
+			if (ret2 != 0) {
+				ret = ret2;
+				goto done;
+			}
+		}
+	}
 
+done:
+	ev->nesting.level--;
 	return ret;
 }
 
diff --git a/lib/tevent/tevent.h b/lib/tevent/tevent.h
index 67946279476..bb36f397395 100644
--- a/lib/tevent/tevent.h
+++ b/lib/tevent/tevent.h
@@ -301,6 +301,12 @@ void tevent_queue_stop(struct tevent_queue *queue);
 
 size_t tevent_queue_length(struct tevent_queue *queue);
 
+typedef int (*tevent_nesting_hook)(struct tevent_context *ev,
+				   void *private_data,
+				   uint32_t level,
+				   bool begin,
+				   void *stack_ptr,
+				   const char *location);
 #ifdef TEVENT_DEPRECATED
 #ifndef _DEPRECATED_
 #if (__GNUC__ >= 3) && (__GNUC_MINOR__ >= 1 )
@@ -310,6 +316,9 @@ size_t tevent_queue_length(struct tevent_queue *queue);
 #endif
 #endif
 void tevent_loop_allow_nesting(struct tevent_context *ev) _DEPRECATED_;
+void tevent_loop_set_nesting_hook(struct tevent_context *ev,
+				  tevent_nesting_hook hook,
+				  void *private_data) _DEPRECATED_;
 #endif
 
 #ifdef TEVENT_COMPAT_DEFINES
diff --git a/lib/tevent/tevent_internal.h b/lib/tevent/tevent_internal.h
index 475d00661a0..f10485398f1 100644
--- a/lib/tevent/tevent_internal.h
+++ b/lib/tevent/tevent_internal.h
@@ -238,6 +238,8 @@ struct tevent_context {
 	struct {
 		bool allowed;
 		uint32_t level;
+		tevent_nesting_hook hook_fn;
+		void *hook_private;
 	} nesting;
 };