# HG changeset patch
# User Kim Alvefur <zash@zash.se>
# Date 1416312304 -3600
# Node ID 67fafebdceb7227657ce24fb176492114208b2e8
# Parent  711fabfe6604828c7cc2ca7bf7d2bba206150e04
mod_storage_gdbm: Storage backend based on lgdbm

diff -r 711fabfe6604 -r 67fafebdceb7 mod_storage_gdbm/mod_storage_gdbm.lua
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mod_storage_gdbm/mod_storage_gdbm.lua	Tue Nov 18 13:05:04 2014 +0100
@@ -0,0 +1,57 @@
+-- mod_storage_gdbm
+-- Copyright (C) 2014 Kim Alvefur
+--
+-- This file is MIT/X11 licensed.
+-- 
+-- Depends on lgdbm:
+-- http://webserver2.tecgraf.puc-rio.br/~lhf/ftp/lua/#lgdbm
+
+local gdbm = require"gdbm";
+local path = require"util.paths";
+local lfs = require"lfs";
+local serialize, deserialize = import("util.serialization", "serialize", "deserialize");
+
+local base_path = path.resolve_relative_path(prosody.paths.data, module.host);
+lfs.mkdir(base_path);
+
+local cache = {};
+
+local driver = {};
+local driver_mt = { __index = driver };
+
+function driver:set(user, value)
+	local ok, err = gdbm.replace(self._db, user or "@", serialize(value));
+	if not ok then return nil, err; end
+	return true;
+end
+
+function driver:get(user)
+	local data, err = gdbm.fetch(self._db, user or "@");
+	if not data then return nil, err; end
+	return deserialize(data);
+end
+
+function open(_, store, typ)
+	typ = typ or "keyval";
+	if typ ~= "keyval" then
+		return nil, "unsupported-store";
+	end
+
+	local db_path = path.join(base_path, store) .. ".db";
+
+	local db = cache[db_path];
+	if not db then
+		db = assert(gdbm.open(db_path, "c"));
+		cache[db_path] = db;
+	end
+	return setmetatable({ _db = db; _path = db_path; store = store, typ = type }, driver_mt);
+end
+
+function module.unload()
+	for path, db in pairs(cache) do
+		gdbm.sync(db);
+		gdbm.close(db);
+	end
+end
+
+module:provides"storage";