libs/core: implement substate() in uci model for creating bound state cursors

diff --git a/libs/core/luasrc/model/uci.lua b/libs/core/luasrc/model/uci.lua
index 66bd0a026ee55634a66ea2c2460158e7c546c48b..46b0db8d82add75cda86f65df6a6c60ad1a86aec 100644 (file)
--- a/libs/core/luasrc/model/uci.lua
+++ b/libs/core/luasrc/model/uci.lua
@@ -227,6 +227,32 @@ function Cursor._affected(self, configlist)
        return reloadlist
 end
 
+--- Create a sub-state of this cursor. The sub-state is tied to the parent
+-- curser, means it the parent unloads or loads configs, the sub state will
+-- do so as well.
+-- @return                     UCI state cursor tied to the parent cursor
+function Cursor.substate(self)
+       Cursor._substates = Cursor._substates or { }
+       Cursor._substates[self] = Cursor._substates[self] or cursor_state()
+       return Cursor._substates[self]
+end
+
+local _load = Cursor.load
+function Cursor.load(self, ...)
+       if Cursor._substates and Cursor._substates[self] then
+               _load(Cursor._substates[self], ...)
+       end
+       return _load(self, ...)
+end
+
+local _unload = Cursor.unload
+function Cursor.unload(self, ...)
+       if Cursor._substates and Cursor._substates[self] then
+               _unload(Cursor._substates[self], ...)
+       end
+       return _unload(self, ...)
+end
+
 
 --- Add an anonymous section.
 -- @class function