Merge remote-tracking branch 'ross/eventarg-v2'

event.c

@@ -125,6 +125,8 @@ struct event_base *event_global_current_base_ = NULL;
 
 static int use_monotonic;
 
+static void *event_self_cbarg_ptr_ = NULL;
+
 /* Prototypes */
 static inline int event_add_internal(struct event *ev,
     const struct timeval *tv, int tv_is_absolute);
@@ -1844,6 +1846,8 @@ event_assign(struct event *ev, struct event_base *base, evutil_socket_t fd, shor
 {
 	if (!base)
 		base = current_base;
+	if (arg == &event_self_cbarg_ptr_)
+		arg = ev;
 
 	event_debug_assert_not_added_(ev);
 
@@ -1910,6 +1914,12 @@ event_set(struct event *ev, evutil_socket_t fd, short events,
 	EVUTIL_ASSERT(r == 0);
 }
 
+void *
+event_self_cbarg(void)
+{
+	return &event_self_cbarg_ptr_;
+}
+
 struct event *
 event_new(struct event_base *base, evutil_socket_t fd, short events, void (*cb)(evutil_socket_t, short, void *), void *arg)
 {
@@ -1917,6 +1927,8 @@ event_new(struct event_base *base, evutil_socket_t fd, short events, void (*cb)(
 	ev = mm_malloc(sizeof(struct event));
 	if (ev == NULL)
 		return (NULL);
+	if (arg == &event_self_cbarg_ptr_)
+		arg = ev;
 	if (event_assign(ev, base, fd, events, cb, arg) < 0) {
 		mm_free(ev);
 		return (NULL);

include/event2/event.h

@@ -845,6 +845,30 @@ int event_base_got_break(struct event_base *);
  */
 typedef void (*event_callback_fn)(evutil_socket_t, short, void *);
 
+/**
+  Return a value used to specify that the event itself must be used as the callback argument.
+
+  The function event_new() takes a callback argument which is passed
+  to the event's callback function. To specify that the argument to be
+  passed to the callback function is the event that event_new() returns,
+  pass in the return value of event_self_cbarg() as the callback argument
+  for event_new().
+
+  For example:
+  <pre>
+      struct event *ev = event_new(base, sock, events, callback, %event_self_cbarg());
+  </pre>
+
+  For consistency with event_new(), it is possible to pass the return value
+  of this function as the callback argument for event_assign() &ndash; this
+  achieves the same result as passing the event in directly.
+
+  @return a value to be passed as the callback argument to event_new() or
+  event_assign().
+  @see event_new(), event_assign()
+ */
+void *event_self_cbarg(void);
+
 /**
   Allocate and asssign a new event structure, ready to be added.
 

sample/signal-test.c

@@ -24,7 +24,7 @@
 #include <string.h>
 #include <errno.h>
 
-#include <event.h>
+#include <event2/event.h>
 
 #ifdef EVENT____func__
 #define __func__ EVENT____func__
@@ -37,7 +37,7 @@ signal_cb(evutil_socket_t fd, short event, void *arg)
 {
 	struct event *signal = arg;
 
-	printf("%s: got signal %d\n", __func__, EVENT_SIGNAL(signal));
+	printf("%s: got signal %d\n", __func__, event_get_signal(signal));
 
 	if (called >= 2)
 		event_del(signal);
@@ -48,7 +48,7 @@ signal_cb(evutil_socket_t fd, short event, void *arg)
 int
 main(int argc, char **argv)
 {
-	struct event signal_int;
+	struct event *signal_int;
 	struct event_base* base;
 #ifdef _WIN32
 	WORD wVersionRequested;
@@ -64,10 +64,9 @@ main(int argc, char **argv)
 	base = event_base_new();
 
 	/* Initalize one event */
-	event_assign(&signal_int, base, SIGINT, EV_SIGNAL|EV_PERSIST, signal_cb,
-	    &signal_int);
+	signal_int = evsignal_new(base, SIGINT, signal_cb, event_self_cbarg());
 
-	event_add(&signal_int, NULL);
+	event_add(signal_int, NULL);
 
 	event_base_dispatch(base);
 	event_base_free(base);

test/regress.c

@@ -1227,6 +1227,42 @@ end:
 	event_del(&ev1);
 }
 
+static void
+event_selfarg_cb(evutil_socket_t fd, short event, void *arg)
+{
+	struct event *ev = arg;
+	struct event_base *base = event_get_base(ev);
+	event_base_assert_ok_(base);
+	event_base_loopexit(base, NULL);
+}
+
+static void
+test_event_new_selfarg(void *ptr)
+{
+	struct basic_test_data *data = ptr;
+	struct event_base *base = data->base;
+	struct event *ev = event_new(base, -1, EV_READ, event_selfarg_cb,
+                                     event_self_cbarg());
+
+	event_active(ev, EV_READ, 1);
+	event_base_dispatch(base);
+
+	event_free(ev);
+}
+
+static void
+test_event_assign_selfarg(void *ptr)
+{
+	struct basic_test_data *data = ptr;
+	struct event_base *base = data->base;
+	struct event ev;
+
+	event_assign(&ev, base, -1, EV_READ, event_selfarg_cb,
+                     event_self_cbarg());
+	event_active(&ev, EV_READ, 1);
+	event_base_dispatch(base);
+}
+
 static void
 test_bad_assign(void *ptr)
 {
@@ -2335,6 +2371,8 @@ struct testcase_t main_testcases[] = {
 	BASIC(free_active_base, TT_FORK|TT_NEED_SOCKETPAIR),
 
 	BASIC(manipulate_active_events, TT_FORK|TT_NEED_BASE),
+	BASIC(event_new_selfarg, TT_FORK|TT_NEED_BASE),
+	BASIC(event_assign_selfarg, TT_FORK|TT_NEED_BASE),
 
 	BASIC(bad_assign, TT_FORK|TT_NEED_BASE|TT_NO_LOGS),
 	BASIC(bad_reentrant, TT_FORK|TT_NEED_BASE|TT_NO_LOGS),