events: Rework event subsystem (add_event, send_event) to be more versatile.

add_event_ex is added that takes an extra user_data pointer. This pointer is
passed to the callback (add_event and add_event_ex have slightly different
callbacks types). All callbacks also get the event id passed. Events added
with add_event_ex must be removed with remove_event_ex because the user_data
pointer must match in addition to the callback pointer.

On the other add_event is simplified to omit the oneshort parameter which
was almost always false (still there with add_event_ex).

As a side effect the ata_idle_notify callbacks are changed as well, they
do not take a data parameter anymore which was always NULL anyway.

This commit also adds some documentation to events.h

Change-Id: I13e29a0f88ef908f175b376d83550f9e0231f772

1 files changed, 3 insertions, 4 deletions

diff --git a/apps/plugins/battery_bench.c b/apps/plugins/battery_bench.c
index 93876d0..174a589 100644
--- a/apps/plugins/battery_bench.c
+++ b/apps/plugins/battery_bench.c
@@ -359,9 +359,8 @@ static unsigned int charge_state(void)
 #endif
 
 
-static void flush_buffer(void* data)
+static void flush_buffer(void)
 {
-    (void)data;
     int fd;
     unsigned int i;
 
@@ -445,7 +444,7 @@ static void thread(void)
            for this to occur because it requires > 16 hours of no disk activity.
          */
         if (buf_idx == BUF_ELEMENTS) {
-            flush_buffer(NULL);
+            flush_buffer();
         }
         
         /* sleep some time until next measurement */
@@ -479,7 +478,7 @@ static void thread(void)
     /* unregister flush callback and flush to disk */
     rb->unregister_storage_idle_func(flush_buffer, true);
 #else
-    flush_buffer(NULL);
+    flush_buffer();
 #endif
     
     /* log end of bench and exit reason */