[evolution-patches] patch of bug 51187 on bugzilla

[Alfred Peng <alfred peng sun com>]

Dear rodrigo,
    I have a patch of bug 51187 on bugzilla.
     My evolution version is uptodate, and cvs download from trunk on 
2004-3-9.

    You can reproduce the problem following the steps:
       1.Create a  appointment in the calender today.
       2.setup up a alarm for this appointment.
       3.Drag and Drop this appointment to another day, before or after.
   result:
      evolution-alarm-notify crash

   Stepping into the source code, I found that the main problem is in 
the file calendar/gui/alarm-notify/alarm-queue.c, function 
"query_objects_changed_cb".
   When returning from the function "e_cal_get_alarms_for_object", the 
variable "alarms" or "alarms->alarms"maybe NULL. And then, if we've 
added the component to the hash table before,  we can get the 
corresponding "cqa" to the variable "uid". The 
program evolution-alarm-notify will be in trouble.
   In some conditions, the "alarms" is NULL, and trouble happened at 
the code "(sl = cqa->alarms->alarms; sl; sl = sl->next)"; In some other 
conditions, the "alarms->alarms" is NULL, and evolution-alarm-notify 
will crash in the function "remove_comp", the code "g_assert 
(cqa->queued_alarms != NULL)" will failed.
   So my opinion is to check the "alarms" and the "alarms->alarms" 
before proceeding, just as the patch shows. If one of the two variables 
is NULL, just remove the alarms. Otherwise, update it in the following 
steps.
  
   By the way, I don't understand the usage of the member variable 
"expecting_update" clearly.

   I'm looking for your answering.
   Thanks a lot.


Regards
Alfred Peng

? evolution/calendar/gui/alarm-notify/.alarm-queue.c.swp
Index: evolution/calendar/gui/alarm-notify/alarm-queue.c
===================================================================
RCS file: /cvs/gnome/evolution/calendar/gui/alarm-notify/alarm-queue.c,v
retrieving revision 1.59
diff -u -r1.59 alarm-queue.c
--- evolution/calendar/gui/alarm-notify/alarm-queue.c	4 Mar 2004 11:38:58 -0000	1.59
+++ evolution/calendar/gui/alarm-notify/alarm-queue.c	10 Mar 2004 10:20:51 -0000
@@ -541,6 +541,13 @@
 			return;
 		}
 
+		/* if the alarms or the alarms list is empty, just remove it */
+		if (alarms == NULL || alarms->alarms == NULL) {
+			if (alarms)
+				e_cal_component_alarms_free (alarms);
+			continue;
+		}
+
 		cqa = lookup_comp_queued_alarms (ca, uid);
 		if (!cqa)
 			add_component_alarms (ca, alarms);
@@ -575,11 +582,7 @@
 				cqa->queued_alarms = g_slist_prepend (cqa->queued_alarms, qa);
 			}
 
-			if (cqa->queued_alarms == NULL) {
-				if (!cqa->expecting_update)
-					remove_comp (ca, uid);
-			} else
-				cqa->queued_alarms = g_slist_reverse (cqa->queued_alarms);
+			cqa->queued_alarms = g_slist_reverse (cqa->queued_alarms);
 		}
 	}
 }