Handle empty iterators.

3 files changed, 39 insertions, 32 deletions

diff --git a/mono/Arguments.cs b/mono/Arguments.cs
index d5407a5d..9b191a67 100644
--- a/mono/Arguments.cs
+++ b/mono/Arguments.cs
@@ -181,15 +181,17 @@ namespace DBus
       string key = "";
 
       // Iterate through the parameters getting the type codes to a string
-      dbus_message_iter_init(message.RawMessage, iter);
+      bool empty = dbus_message_iter_init(message.RawMessage, iter);
 
-      do {
-	char code = (char) dbus_message_iter_get_arg_type(iter);
-	if (code == '\0')
-	  return key;
-	
-	key += code;
-      } while (dbus_message_iter_next(iter));
+      if (!empty) {
+	do {
+	  char code = (char) dbus_message_iter_get_arg_type(iter);
+	  if (code == '\0')
+	    return key;
+	  
+	  key += code;
+	} while (dbus_message_iter_next(iter));
+      }
       
       Marshal.FreeCoTaskMem(iter);
 
@@ -219,6 +221,7 @@ namespace DBus
     {
       private Arguments arguments;
       private bool started = false;
+      private bool empty = false;
       private IntPtr iter = Marshal.AllocCoTaskMem(Arguments.DBusMessageIterSize);
       
       public ArgumentsEnumerator(Arguments arguments)
@@ -238,13 +241,13 @@ namespace DBus
 	  return dbus_message_iter_next(iter);
 	} else {
 	  started = true;
-	  return true;
+	  return !empty;
 	}
       }
       
       public void Reset()
       {
-	dbus_message_iter_init(arguments.message.RawMessage, iter);
+	empty = dbus_message_iter_init(arguments.message.RawMessage, iter);
 	started = false;
       }
       
@@ -274,7 +277,7 @@ namespace DBus
     private extern static bool dbus_message_iter_next(IntPtr iter);
 
     [DllImport("dbus-1")]
-    private extern static void dbus_message_iter_init(IntPtr rawMessage, IntPtr iter);
+    private extern static bool dbus_message_iter_init(IntPtr rawMessage, IntPtr iter);
 
     [DllImport("dbus-1")]
     private extern static int dbus_message_iter_get_arg_type(IntPtr iter);
diff --git a/mono/DBusType/Array.cs b/mono/DBusType/Array.cs
index 34a842c7..917fa780 100644
--- a/mono/DBusType/Array.cs
+++ b/mono/DBusType/Array.cs
@@ -36,18 +36,20 @@ namespace DBus.DBusType
       IntPtr arrayIter = Marshal.AllocCoTaskMem(Arguments.DBusMessageIterSize);
       
       int elementTypeCode;
-      dbus_message_iter_init_array_iterator(iter, arrayIter, out elementTypeCode);
+      bool empty = dbus_message_iter_init_array_iterator(iter, arrayIter, out elementTypeCode);
       this.elementType = (Type) Arguments.DBusTypes[(char) elementTypeCode];
 
       elements = new ArrayList();
 
-      do {
-	object [] pars = new Object[2];
-	pars[0] = arrayIter;
-	pars[1] = service;
-	DBusType.IDBusType dbusType = (DBusType.IDBusType) Activator.CreateInstance(elementType, pars);
-	elements.Add(dbusType);
-      } while (dbus_message_iter_next(arrayIter));
+      if (!empty) {
+	do {
+	  object [] pars = new Object[2];
+	  pars[0] = arrayIter;
+	  pars[1] = service;
+	  DBusType.IDBusType dbusType = (DBusType.IDBusType) Activator.CreateInstance(elementType, pars);
+	  elements.Add(dbusType);
+	} while (dbus_message_iter_next(arrayIter));
+      }
       
       Marshal.FreeCoTaskMem(arrayIter);
     }
@@ -118,7 +120,7 @@ namespace DBus.DBusType
     }    
 
     [DllImport("dbus-1")]
-    private extern static void dbus_message_iter_init_array_iterator(IntPtr iter,
+    private extern static bool dbus_message_iter_init_array_iterator(IntPtr iter,
 								     IntPtr arrayIter,
 								     out int elementType);
  
diff --git a/mono/DBusType/Dict.cs b/mono/DBusType/Dict.cs
index bd649434..e93d7d77 100644
--- a/mono/DBusType/Dict.cs
+++ b/mono/DBusType/Dict.cs
@@ -31,20 +31,22 @@ namespace DBus.DBusType
     {
       IntPtr dictIter = Marshal.AllocCoTaskMem(Arguments.DBusMessageIterSize);
       
-      dbus_message_iter_init_dict_iterator(iter, dictIter);
+      bool empty = dbus_message_iter_init_dict_iterator(iter, dictIter);
 
       this.val = new Hashtable();
 
-      do {
-	string key = dbus_message_iter_get_dict_key(dictIter);
-
-	// Get the argument type and get the value
-	Type elementType = (Type) DBus.Arguments.DBusTypes[(char) dbus_message_iter_get_arg_type(dictIter)];
-	object [] pars = new Object[1];
-	pars[0] = dictIter;
-	DBusType.IDBusType dbusType = (DBusType.IDBusType) Activator.CreateInstance(elementType, pars);
-	this.val.Add(key, dbusType);
-      } while (dbus_message_iter_next(dictIter));
+      if (!empty) {
+	do {
+	  string key = dbus_message_iter_get_dict_key(dictIter);
+	  
+	  // Get the argument type and get the value
+	  Type elementType = (Type) DBus.Arguments.DBusTypes[(char) dbus_message_iter_get_arg_type(dictIter)];
+	  object [] pars = new Object[1];
+	  pars[0] = dictIter;
+	  DBusType.IDBusType dbusType = (DBusType.IDBusType) Activator.CreateInstance(elementType, pars);
+	  this.val.Add(key, dbusType);
+	} while (dbus_message_iter_next(dictIter));
+      }
       
       Marshal.FreeCoTaskMem(dictIter);
     }
@@ -120,7 +122,7 @@ namespace DBus.DBusType
     }    
 
     [DllImport("dbus-1")]
-    private extern static void dbus_message_iter_init_dict_iterator(IntPtr iter,
+    private extern static bool dbus_message_iter_init_dict_iterator(IntPtr iter,
 								    IntPtr dictIter);
  
     [DllImport("dbus-1")]