1 files changed, 177 insertions, 0 deletions
diff --git a/util/multitable.lua b/util/multitable.lua
new file mode 100644
index 00000000..dbf34d28
--- /dev/null
+++ b/util/multitable.lua
@@ -0,0 +1,177 @@
+-- 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.
+--
+
+local select = select;
+local t_insert = table.insert;
+local unpack, pairs, next, type = unpack, pairs, next, type;
+
+module "multitable"
+
+local function get(self, ...)
+	local t = self.data;
+	for n = 1,select('#', ...) do
+		t = t[select(n, ...)];
+		if not t then break; end
+	end
+	return t;
+end
+
+local function add(self, ...)
+	local t = self.data;
+	local count = select('#', ...);
+	for n = 1,count-1 do
+		local key = select(n, ...);
+		local tab = t[key];
+		if not tab then tab = {}; t[key] = tab; end
+		t = tab;
+	end
+	t_insert(t, (select(count, ...)));
+end
+
+local function set(self, ...)
+	local t = self.data;
+	local count = select('#', ...);
+	for n = 1,count-2 do
+		local key = select(n, ...);
+		local tab = t[key];
+		if not tab then tab = {}; t[key] = tab; end
+		t = tab;
+	end
+	t[(select(count-1, ...))] = (select(count, ...));
+end
+
+local function r(t, n, _end, ...)
+	if t == nil then return; end
+	local k = select(n, ...);
+	if n == _end then
+		t[k] = nil;
+		return;
+	end
+	if k then
+		local v = t[k];
+		if v then
+			r(v, n+1, _end, ...);
+			if not next(v) then
+				t[k] = nil;
+			end
+		end
+	else
+		for _,b in pairs(t) do
+			r(b, n+1, _end, ...);
+			if not next(b) then
+				t[_] = nil;
+			end
+		end
+	end
+end
+
+local function remove(self, ...)
+	local _end = select('#', ...);
+	for n = _end,1 do
+		if select(n, ...) then _end = n; break; end
+	end
+	r(self.data, 1, _end, ...);
+end
+
+
+local function s(t, n, results, _end, ...)
+	if t == nil then return; end
+	local k = select(n, ...);
+	if n == _end then
+		if k == nil then
+			for _, v in pairs(t) do
+				t_insert(results, v);
+			end
+		else
+			t_insert(results, t[k]);
+		end
+		return;
+	end
+	if k then
+		local v = t[k];
+		if v then
+			s(v, n+1, results, _end, ...);
+		end
+	else
+		for _,b in pairs(t) do
+			s(b, n+1, results, _end, ...);
+		end
+	end
+end
+
+-- Search for keys, nil == wildcard
+local function search(self, ...)
+	local _end = select('#', ...);
+	for n = _end,1 do
+		if select(n, ...) then _end = n; break; end
+	end
+	local results = {};
+	s(self.data, 1, results, _end, ...);
+	return results;
+end
+
+-- Append results to an existing list
+local function search_add(self, results, ...)
+	if not results then results = {}; end
+	local _end = select('#', ...);
+	for n = _end,1 do
+		if select(n, ...) then _end = n; break; end
+	end
+	s(self.data, 1, results, _end, ...);
+	return results;
+end
+
+function iter(self, ...)
+	local query = { ... };
+	local maxdepth = select("#", ...);
+	local stack = { self.data };
+	local keys = { };
+	local function it(self)
+		local depth = #stack;
+		local key = next(stack[depth], keys[depth]);
+		if key == nil then -- Go up the stack
+			stack[depth], keys[depth] = nil, nil;
+			if depth > 1 then
+				return it(self);
+			end
+			return; -- The end
+		else
+			keys[depth] = key;
+		end
+		local value = stack[depth][key];
+		if query[depth] == nil or key == query[depth] then
+			if depth == maxdepth then -- Result
+				local result = {}; -- Collect keys forming path to result
+				for i = 1, depth do
+					result[i] = keys[i];
+				end
+				result[depth+1] = value;
+				return unpack(result, 1, depth+1);
+			elseif type(value) == "table" then
+				t_insert(stack, value); -- Descend
+			end
+		end
+		return it(self);
+	end;
+	return it, self;
+end
+
+function new()
+	return {
+		data = {};
+		get = get;
+		add = add;
+		set = set;
+		remove = remove;
+		search = search;
+		search_add = search_add;
+		iter = iter;
+	};
+end
+
+return _M;