src/event_bus.c

@@ -5,6 +5,14 @@
 #include "memory_alloc.h"
 #include "errors.h"
 
+// Arg : void *payload
+int create_event(event_t *event, va_list args)
+{
+    event->payload = va_arg(args, void *);
+
+    return EXIT_SUCCESS;
+}
+
 // Arg : callback_t callback
 int create_subscription(subscription_t *subscription, va_list args)
 {
@@ -13,18 +21,23 @@ int create_subscription(subscription_t *subscription, va_list args)
     return EXIT_SUCCESS;
 }
 
-// Arg : size_t id
+// Args : size_t id, size_t max_history_size
 int create_topic(topic_t *topic, va_list args)
 {
     topic->id = va_arg(args, size_t);
+    topic->max_history_size = va_arg(args, size_t);
 
+    linked_list_init(&topic->events, sizeof(event_t), (allocator_t)create_event, NULL);
     linked_list_init(&topic->subscriptions, sizeof(subscription_t), (allocator_t)create_subscription, NULL);
 
+    if(linked_list_reserve(&topic->events, topic->max_history_size)) return EXIT_FAILURE;
+
     return EXIT_SUCCESS;
 }
 
 int destroy_topic(topic_t *topic)
 {
+    if(linked_list_exit(&topic->events)) return EXIT_FAILURE;
     if(linked_list_exit(&topic->subscriptions)) return EXIT_FAILURE;
 
     return EXIT_SUCCESS;
@@ -83,22 +96,17 @@ int event_bus_change_topic_id(event_bus_t *event_bus, size_t old_id, size_t new_
     return EXIT_SUCCESS;
 }
 
-// Args : va_list_args
+// Args : void *payload
 static inline int action_execute_callback(elem_t *elem, va_list args)
 {
     subscription_t *subscription = elem->data;
 
-    va_list args_copy;
-    va_copy(args_copy, args);
-
-    if(subscription->callback(args_copy)) return EXIT_FAILURE;
-
-    va_end(args_copy);
+    if(subscription->callback(va_arg(args, void *))) return EXIT_FAILURE;
 
     return EXIT_SUCCESS;
 }
 
-int event_bus_publish(event_bus_t *event_bus, size_t id, ...)
+int event_bus_publish(event_bus_t *event_bus, size_t id, void *payload)
 {
     elem_t *topic_elem = linked_list_get_if(&event_bus->topics, condition_is_topic_id, id);
     if(!topic_elem)
@@ -109,14 +117,22 @@ int event_bus_publish(event_bus_t *event_bus, size_t id, ...)
 
     topic_t *topic = topic_elem->data;
 
-    va_list args, args_copy;
-    va_start(args, id);
-    va_copy(args_copy, args);
+    if(topic->events.size + 1 > topic->max_history_size)
+    {
+        elem_t *removed_event_elem = linked_list_pop_back(&topic->events);
+        if(!removed_event_elem) return EXIT_FAILURE;
 
-    if(linked_list_for_eachv(&topic->subscriptions, action_execute_callback, args_copy)) return EXIT_FAILURE;
+        destroy_elem(&topic->events, removed_event_elem);
+    }
 
-    va_end(args_copy);
-    va_end(args);
+    elem_t *event_elem = create_elem(&topic->events, payload);
+    if(!event_elem) return EXIT_FAILURE;
+
+    if(linked_list_push_front(&topic->events, event_elem)) return EXIT_FAILURE;
+
+    if(linked_list_for_each(&topic->subscriptions, action_execute_callback, payload)) return EXIT_FAILURE;
+
+    debug_printf("Event published, id = %lu, payload = %d", id, *(bool*)payload);
 
     return EXIT_SUCCESS;
 }

src/headers/event_bus.h

@@ -2,10 +2,15 @@
 #define EVENT_BUS_H
 
 #include <stdarg.h>
-#include "ecs.h"
 #include "linked_list.h"
 
-typedef int (*callback_t)(va_list args);
+typedef int (*callback_t)(void *payload);
+
+typedef struct event_t {
+    void *payload;
+} event_t;
+
+int create_event(event_t *event, va_list args);
 
 typedef struct subscription_t {
     callback_t callback;
@@ -15,7 +20,9 @@ int create_subscription(subscription_t *subscription, va_list args);
 
 typedef struct topic_t {
     size_t id;
+    linked_list_t events;
     linked_list_t subscriptions;
+    size_t max_history_size;
 } topic_t;
 
 int create_topic(topic_t *topic, va_list args);
@@ -32,7 +39,7 @@ int event_bus_new_topic(event_bus_t *event_bus, size_t id, size_t max_history_si
 int event_bus_remove_topic(event_bus_t *event_bus, size_t id);
 int event_bus_change_topic_id(event_bus_t *event_bus, size_t old_id, size_t new_id);
 
-int event_bus_publish(event_bus_t *event_bus, size_t id, ...);
+int event_bus_publish(event_bus_t *event_bus, size_t id, void *payload);
 int event_bus_subscribe(event_bus_t *event_bus, size_t id, callback_t callback);
 
 #endif // EVENT_BUS_H

src/headers/linked_list.h

@@ -274,16 +274,4 @@ int linked_list_remove_if(linked_list_t *linked_list, const condition_t conditio
 */
 int linked_list_for_each(const linked_list_t *linked_list, const action_t action, ...);
 
-/**
- * @brief Apply an action to every elements in the list.
- * The action can be anything that doesn't destroy the element.
- *
- * @param linked_list   Pointer to an linked list
- * @param action        Action to apply
- * @param args          Argument to pass to the action in the form of a va_list
- *
- * @return EXIT_SUCCESS, EXIT_FAILURE on error.
-*/
-int linked_list_for_eachv(const linked_list_t *linked_list, const action_t action, va_list args);
-
 #endif // LINKED_LIST_H

src/linked_list.c

@@ -478,31 +478,3 @@ int linked_list_for_each(const linked_list_t *linked_list, const action_t action
 
     return EXIT_SUCCESS;
 }
-
-int linked_list_for_eachv(const linked_list_t *linked_list, const action_t action, va_list args)
-{
-    assert("Linked list cannot be NULL" && linked_list);
-    assert("Action cannot be NULL" && action);
-
-    elem_t *current_elem = linked_list->first;
-
-    while(current_elem)
-    {
-        va_list args_copy;
-        va_copy(args_copy, args);
-
-        if(action(current_elem, args_copy))
-        {
-            va_end(args_copy);
-            va_end(args);
-
-            return EXIT_FAILURE;
-        }
-
-        va_end(args_copy);
-
-        current_elem = current_elem->next;
-    }
-
-    return EXIT_SUCCESS;
-}