Merge 0.10->trunk

[prosody.git] / util / filters.lua

diff --git a/util/filters.lua b/util/filters.lua
index 09a81cdb101fb9ccd183333346e0bce7c4b28237..427dcb7cafa14f8cf2f4818393ae9b8221ac6655 100644 (file)
--- a/util/filters.lua
+++ b/util/filters.lua
@@ -1,7 +1,7 @@
 -- Prosody IM
 -- Copyright (C) 2008-2010 Matthew Wild
 -- Copyright (C) 2008-2010 Waqas Hussain
--- 
+--
 -- This project is MIT/X11 licensed. Please see the
 -- COPYING file in the source package for more information.
 --
@@ -10,42 +10,58 @@ local t_insert, t_remove = table.insert, table.remove;
 
 module "filters"
 
-local function initialize_session(session)
-       local filters = {};
-       session.filters = filters;
-       
-       function session.filter(type, data)
-               local filter_list = filters[type];
-               for i = 1, #filter_list do
-                       data = filter_list[i](data);
+local new_filter_hooks = {};
+
+function initialize(session)
+       if not session.filters then
+               local filters = {};
+               session.filters = filters;
+
+               function session.filter(type, data)
+                       local filter_list = filters[type];
+                       if filter_list then
+                               for i = 1, #filter_list do
+                                       data = filter_list[i](data, session);
+                                       if data == nil then break; end
+                               end
+                       end
+                       return data;
                end
-               return data;
        end
+
+       for i=1,#new_filter_hooks do
+               new_filter_hooks[i](session);
+       end
+
+       return session.filter;
 end
 
 function add_filter(session, type, callback, priority)
        if not session.filters then
-               initialize_session(session);
+               initialize(session);
        end
-       
+
        local filter_list = session.filters[type];
        if not filter_list then
                filter_list = {};
                session.filters[type] = filter_list;
+       elseif filter_list[callback] then
+               return; -- Filter already added
        end
-       
+
        priority = priority or 0;
-       
+
        local i = 0;
        repeat
                i = i + 1;
-       until not filter_list[i] or filter_list[filter_list[i]] >= priority;
-       
+       until not filter_list[i] or filter_list[filter_list[i]] < priority;
+
        t_insert(filter_list, i, callback);
        filter_list[callback] = priority;
 end
 
 function remove_filter(session, type, callback)
+       if not session.filters then return; end
        local filter_list = session.filters[type];
        if filter_list and filter_list[callback] then
                for i=1, #filter_list do
@@ -58,4 +74,16 @@ function remove_filter(session, type, callback)
        end
 end
 
-return _M;
\ No newline at end of file
+function add_filter_hook(callback)
+       t_insert(new_filter_hooks, callback);
+end
+
+function remove_filter_hook(callback)
+       for i=1,#new_filter_hooks do
+               if new_filter_hooks[i] == callback then
+                       t_remove(new_filter_hooks, i);
+               end
+       end
+end
+
+return _M;