X-Git-Url: https://gerrit.automotivelinux.org/gerrit/gitweb?a=blobdiff_plain;f=src%2Fafb-evt.c;h=88b6d6032dc4e0385ef794c41d9aca1665cca788;hb=b6ad3eb5c49252c989e0d8ecd2664aae10e8db8b;hp=a99dc89408b8630797f1021227875af5d6fbb737;hpb=31f85d741a3f35f853114e0bc299213f4456fcbc;p=src%2Fapp-framework-binder.git

diff --git a/src/afb-evt.c b/src/afb-evt.c
index a99dc894..88b6d603 100644
--- a/src/afb-evt.c
+++ b/src/afb-evt.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2015, 2016 "IoT.bzh"
+ * Copyright (C) 2015, 2016, 2017 "IoT.bzh"
  * Author "Fulup Ar Foll"
  * Author José Bollo <jose.bollo@iot.bzh>
  *
@@ -22,6 +22,7 @@
 #include <string.h>
 #include <assert.h>
 #include <errno.h>
+#include <pthread.h>
 
 #include <json-c/json.h>
 #include <afb/afb-event-itf.h>
@@ -38,8 +39,8 @@ struct afb_evt_listener {
 	/* chaining listeners */
 	struct afb_evt_listener *next;
 
-	/* callback on event */
-	void (*send)(void *closure, const char *event, struct json_object *object);
+	/* interface for callbacks */
+	const struct afb_evt_itf *itf;
 
 	/* closure for the callback */
 	void *closure;
@@ -47,6 +48,9 @@ struct afb_evt_listener {
 	/* head of the list of events listened */
 	struct afb_evt_watch *watchs;
 
+	/* mutex of the listener */
+	pthread_mutex_t mutex;
+
 	/* count of reference to the listener */
 	int refcount;
 };
@@ -56,9 +60,18 @@ struct afb_evt_listener {
  */
 struct afb_evt_event {
 
+	/* next event */
+	struct afb_evt_event *next;
+
 	/* head of the list of listeners watching the event */
 	struct afb_evt_watch *watchs;
 
+	/* id of the event */
+	int id;
+
+	/* mutex of the event */
+	pthread_mutex_t mutex;
+
 	/* name of the event */
 	char name[1];
 };
@@ -79,23 +92,35 @@ struct afb_evt_watch {
 
 	/* link to the next event for the same listener */
 	struct afb_evt_watch *next_by_listener;
+
+	/* activity */
+	unsigned activity;
 };
 
 /* declare functions */
 static int evt_broadcast(struct afb_evt_event *evt, struct json_object *obj);
 static int evt_push(struct afb_evt_event *evt, struct json_object *obj);
 static void evt_destroy(struct afb_evt_event *evt);
+static const char *evt_name(struct afb_evt_event *evt);
 
 /* the interface for events */
 static struct afb_event_itf afb_evt_event_itf = {
 	.broadcast = (void*)evt_broadcast,
 	.push = (void*)evt_push,
-	.drop = (void*)evt_destroy
+	.drop = (void*)evt_destroy,
+	.name = (void*)evt_name
 };
 
 /* head of the list of listeners */
+static pthread_mutex_t listeners_mutex = PTHREAD_MUTEX_INITIALIZER;
 static struct afb_evt_listener *listeners = NULL;
 
+/* handling id of events */
+static pthread_mutex_t events_mutex = PTHREAD_MUTEX_INITIALIZER;
+static struct afb_evt_event *events = NULL;
+static int event_id_counter = 0;
+static int event_id_wrapped = 0;
+
 /*
  * Broadcasts the event 'evt' with its 'object'
  * 'object' is released (like json_object_put)
@@ -117,19 +142,23 @@ int afb_evt_broadcast(const char *event, struct json_object *object)
 	struct afb_evt_listener *listener;
 
 	result = 0;
+	pthread_mutex_lock(&listeners_mutex);
 	listener = listeners;
 	while(listener) {
-		listener->send(listener->closure, event, json_object_get(object));
+		if (listener->itf->broadcast != NULL) {
+			listener->itf->broadcast(listener->closure, event, 0, json_object_get(object));
+			result++;
+		}
 		listener = listener->next;
-		result++;
 	}
+	pthread_mutex_unlock(&listeners_mutex);
 	json_object_put(object);
 	return result;
 }
 
 /*
- * Broadcasts the event 'evt' with its 'object'
- * 'object' is released (like json_object_put)
+ * Pushes the event 'evt' with 'obj' to its listeners
+ * 'obj' is released (like json_object_put)
  * Returns the count of listener taht received the event.
  */
 static int evt_push(struct afb_evt_event *evt, struct json_object *obj)
@@ -139,32 +168,52 @@ static int evt_push(struct afb_evt_event *evt, struct json_object *obj)
 	struct afb_evt_listener *listener;
 
 	result = 0;
+	pthread_mutex_lock(&evt->mutex);
 	watch = evt->watchs;
-	while(listener) {
+	while(watch) {
 		listener = watch->listener;
-		listener->send(listener->closure, evt->name, json_object_get(obj));
+		assert(listener->itf->push != NULL);
+		if (watch->activity != 0)
+			listener->itf->push(listener->closure, evt->name, evt->id, json_object_get(obj));
 		watch = watch->next_by_event;
 		result++;
 	}
+	pthread_mutex_unlock(&evt->mutex);
 	json_object_put(obj);
 	return result;
 }
 
+/*
+ * Returns the name associated to the event 'evt'.
+ */
+static const char *evt_name(struct afb_evt_event *evt)
+{
+	return evt->name;
+}
+
 /*
  * remove the 'watch'
  */
 static void remove_watch(struct afb_evt_watch *watch)
 {
 	struct afb_evt_watch **prv;
+	struct afb_evt_event *evt;
+	struct afb_evt_listener *listener;
+
+	/* notify listener if needed */
+	evt = watch->event;
+	listener = watch->listener;
+	if (watch->activity != 0 && listener->itf->remove != NULL)
+		listener->itf->remove(listener->closure, evt->name, evt->id);
 
 	/* unlink the watch for its event */
-	prv = &watch->event->watchs;
+	prv = &evt->watchs;
 	while(*prv != watch)
 		prv = &(*prv)->next_by_event;
 	*prv = watch->next_by_event;
 
 	/* unlink the watch for its listener */
-	prv = &watch->listener->watchs;
+	prv = &listener->watchs;
 	while(*prv != watch)
 		prv = &(*prv)->next_by_listener;
 	*prv = watch->next_by_listener;
@@ -178,11 +227,37 @@ static void remove_watch(struct afb_evt_watch *watch)
  */
 static void evt_destroy(struct afb_evt_event *evt)
 {
+	int found;
+	struct afb_evt_event **prv;
+	struct afb_evt_listener *listener;
+
 	if (evt != NULL) {
-		/* removes all watchers */
-		while(evt->watchs != NULL)
-			remove_watch(evt->watchs);
-		free(evt);
+		/* unlinks the event if valid! */
+		pthread_mutex_lock(&events_mutex);
+		found = 0;
+		prv = &events;
+		while (*prv && !(found = (*prv == evt)))
+			prv = &(*prv)->next;
+		if (found)
+			*prv = evt->next;
+		pthread_mutex_unlock(&events_mutex);
+
+		/* destroys the event */
+		if (found) {
+			/* removes all watchers */
+			while(evt->watchs != NULL) {
+				listener = evt->watchs->listener;
+				pthread_mutex_lock(&listener->mutex);
+				pthread_mutex_lock(&evt->mutex);
+				remove_watch(evt->watchs);
+				pthread_mutex_unlock(&evt->mutex);
+				pthread_mutex_unlock(&listener->mutex);
+			}
+
+			/* free */
+			pthread_mutex_destroy(&evt->mutex);
+			free(evt);
+		}
 	}
 }
 
@@ -195,13 +270,59 @@ struct afb_event afb_evt_create_event(const char *name)
 	size_t len;
 	struct afb_evt_event *evt;
 
+	/* allocates the event */
 	len = strlen(name);
 	evt = malloc(len + sizeof * evt);
-	if (evt != NULL) {
-		evt->watchs = NULL;
-		memcpy(evt->name, name, len + 1);
-	}
+	if (evt == NULL)
+		goto error;
+
+	/* initialize the event */
+	evt->watchs = NULL;
+	memcpy(evt->name, name, len + 1);
+
+	/* allocates the id */
+	pthread_mutex_lock(&events_mutex);
+	do {
+		if (++event_id_counter < 0) {
+			event_id_wrapped = 1;
+			event_id_counter = 1024; /* heuristic: small numbers are not destroyed */
+		}
+		if (!event_id_wrapped)
+			break;
+		evt = events;
+		while(evt != NULL && evt->id != event_id_counter)
+			evt = evt->next;
+	} while (evt != NULL);
+
+	/* initialize the event */
+	memcpy(evt->name, name, len + 1);
+	evt->next = events;
+	evt->watchs = NULL;
+	evt->id = event_id_counter;
+	pthread_mutex_init(&evt->mutex, NULL);
+	events = evt;
+	pthread_mutex_unlock(&events_mutex);
+
+	/* returns the event */
 	return (struct afb_event){ .itf = &afb_evt_event_itf, .closure = evt };
+error:
+	return (struct afb_event){ .itf = NULL, .closure = NULL };
+}
+
+/*
+ * Returns the name of the 'event'
+ */
+const char *afb_evt_event_name(struct afb_event event)
+{
+	return (event.itf != &afb_evt_event_itf) ? NULL : ((struct afb_evt_event *)event.closure)->name;
+}
+
+/*
+ * Returns the id of the 'event'
+ */
+int afb_evt_event_id(struct afb_event event)
+{
+	return (event.itf != &afb_evt_event_itf) ? 0 : ((struct afb_evt_event *)event.closure)->id;
 }
 
 /*
@@ -209,15 +330,18 @@ struct afb_event afb_evt_create_event(const char *name)
  * and the 'closure'.
  * Returns NULL in case of memory depletion.
  */
-struct afb_evt_listener *afb_evt_listener_create(void (*send)(void *closure, const char *event, struct json_object *object), void *closure)
+struct afb_evt_listener *afb_evt_listener_create(const struct afb_evt_itf *itf, void *closure)
 {
 	struct afb_evt_listener *listener;
 
 	/* search if an instance already exists */
+	pthread_mutex_lock(&listeners_mutex);
 	listener = listeners;
 	while (listener != NULL) {
-		if (listener->send == send && listener->closure == closure)
-			return afb_evt_listener_addref(listener);
+		if (listener->itf == itf && listener->closure == closure) {
+			listener = afb_evt_listener_addref(listener);
+			goto found;
+		}
 		listener = listener->next;
 	}
 
@@ -225,13 +349,16 @@ struct afb_evt_listener *afb_evt_listener_create(void (*send)(void *closure, con
 	listener = calloc(1, sizeof *listener);
 	if (listener != NULL) {
 		/* init */
-		listener->next = listeners;
-		listener->send = send;
+		listener->itf = itf;
 		listener->closure = closure;
 		listener->watchs = NULL;
 		listener->refcount = 1;
+		pthread_mutex_init(&listener->mutex, NULL);
+		listener->next = listeners;
 		listeners = listener;
 	}
+ found:
+	pthread_mutex_unlock(&listeners_mutex);
 	return listener;
 }
 
@@ -240,7 +367,7 @@ struct afb_evt_listener *afb_evt_listener_create(void (*send)(void *closure, con
  */
 struct afb_evt_listener *afb_evt_listener_addref(struct afb_evt_listener *listener)
 {
-	listener->refcount++;
+	__atomic_add_fetch(&listener->refcount, 1, __ATOMIC_RELAXED);
 	return listener;
 }
 
@@ -250,20 +377,31 @@ struct afb_evt_listener *afb_evt_listener_addref(struct afb_evt_listener *listen
  */
 void afb_evt_listener_unref(struct afb_evt_listener *listener)
 {
-	if (0 == --listener->refcount) {
-		struct afb_evt_listener **prv;
+	struct afb_evt_listener **prv;
+	struct afb_evt_event *evt;
 
-		/* remove the watchers */
-		while (listener->watchs != NULL)
-			remove_watch(listener->watchs);
+	if (!__atomic_sub_fetch(&listener->refcount, 1, __ATOMIC_RELAXED)) {
 
 		/* unlink the listener */
+		pthread_mutex_lock(&listeners_mutex);
 		prv = &listeners;
 		while (*prv != listener)
 			prv = &(*prv)->next;
 		*prv = listener->next;
+		pthread_mutex_unlock(&listeners_mutex);
+
+		/* remove the watchers */
+		pthread_mutex_lock(&listener->mutex);
+		while (listener->watchs != NULL) {
+			evt = listener->watchs->event;
+			pthread_mutex_lock(&evt->mutex);
+			remove_watch(listener->watchs);
+			pthread_mutex_unlock(&evt->mutex);
+		}
+		pthread_mutex_unlock(&listener->mutex);
 
 		/* free the listener */
+		pthread_mutex_destroy(&listener->mutex);
 		free(listener);
 	}
 }
@@ -278,35 +416,46 @@ int afb_evt_add_watch(struct afb_evt_listener *listener, struct afb_event event)
 	struct afb_evt_event *evt;
 
 	/* check parameter */
-	if (event.itf != &afb_evt_event_itf) {
+	if (event.itf != &afb_evt_event_itf || listener->itf->push == NULL) {
 		errno = EINVAL;
 		return -1;
 	}
 
-	/* search the existing watch */
+	/* search the existing watch for the listener */
+	evt = event.closure;
+	pthread_mutex_lock(&listener->mutex);
 	watch = listener->watchs;
 	while(watch != NULL) {
-		if (watch->event == event.closure)
-			return 0;
+		if (watch->event == evt)
+			goto found;
 		watch = watch->next_by_listener;
 	}
 
 	/* not found, allocate a new */
 	watch = malloc(sizeof *watch);
 	if (watch == NULL) {
+		pthread_mutex_unlock(&listener->mutex);
 		errno = ENOMEM;
 		return -1;
 	}
 
 	/* initialise and link */
-	evt = event.closure;
 	watch->event = evt;
-	watch->next_by_event = evt->watchs;
+	watch->activity = 0;
 	watch->listener = listener;
 	watch->next_by_listener = listener->watchs;
-	evt->watchs = watch;
 	listener->watchs = watch;
-	
+	pthread_mutex_lock(&evt->mutex);
+	watch->next_by_event = evt->watchs;
+	evt->watchs = watch;
+	pthread_mutex_unlock(&evt->mutex);
+
+found:
+	if (watch->activity == 0 && listener->itf->add != NULL)
+		listener->itf->add(listener->closure, evt->name, evt->id);
+	watch->activity++;
+	pthread_mutex_unlock(&listener->mutex);
+
 	return 0;
 }
 
@@ -317,6 +466,7 @@ int afb_evt_add_watch(struct afb_evt_listener *listener, struct afb_event event)
 int afb_evt_remove_watch(struct afb_evt_listener *listener, struct afb_event event)
 {
 	struct afb_evt_watch *watch;
+	struct afb_evt_event *evt;
 
 	/* check parameter */
 	if (event.itf != &afb_evt_event_itf) {
@@ -325,16 +475,24 @@ int afb_evt_remove_watch(struct afb_evt_listener *listener, struct afb_event eve
 	}
 
 	/* search the existing watch */
+	evt = event.closure;
+	pthread_mutex_lock(&listener->mutex);
 	watch = listener->watchs;
 	while(watch != NULL) {
-		if (watch->event == event.closure) {
+		if (watch->event == evt) {
 			/* found: remove it */
-			remove_watch(watch);
-			break;
+			if (watch->activity != 0) {
+				watch->activity--;
+				if (watch->activity == 0 && listener->itf->remove != NULL)
+					listener->itf->remove(listener->closure, evt->name, evt->id);
+			}
+			pthread_mutex_unlock(&listener->mutex);
+			return 0;
 		}
 		watch = watch->next_by_listener;
 	}
-	return 0;
+	pthread_mutex_unlock(&listener->mutex);
+	errno = ENOENT;
+	return -1;
 }
 
-