aboutsummaryrefslogtreecommitdiffstats
path: root/util/datamanager.lua
blob: 9207f555d1bf0b0133d18f88e9715ccf3613fad6 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
-- 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 format = string.format;
local setmetatable = setmetatable;
local ipairs = ipairs;
local char = string.char;
local pcall = pcall;
local log = require "util.logger".init("datamanager");
local io_open = io.open;
local os_remove = os.remove;
local os_rename = os.rename;
local tonumber = tonumber;
local next = next;
local t_insert = table.insert;
local t_concat = table.concat;
local envloadfile = require"util.envload".envloadfile;
local serialize = require "util.serialization".serialize;
local path_separator = assert ( package.config:match ( "^([^\n]+)" ) , "package.config not in standard form" ) -- Extract directory seperator from package.config (an undocumented string that comes with lua)
local lfs = require "lfs";
local prosody = prosody;

local raw_mkdir = lfs.mkdir;
local function fallocate(f, offset, len)
	-- This assumes that current position == offset
	local fake_data = (" "):rep(len);
	local ok, msg = f:write(fake_data);
	if not ok then
		return ok, msg;
	end
	f:seek("set", offset);
	return true;
end;
pcall(function()
	local pposix = require "util.pposix";
	raw_mkdir = pposix.mkdir or raw_mkdir; -- Doesn't trample on umask
	fallocate = pposix.fallocate or fallocate;
end);

module "datamanager"

---- utils -----
local encode, decode;
do
	local urlcodes = setmetatable({}, { __index = function (t, k) t[k] = char(tonumber("0x"..k)); return t[k]; end });

	decode = function (s)
		return s and (s:gsub("+", " "):gsub("%%([a-fA-F0-9][a-fA-F0-9])", urlcodes));
	end

	encode = function (s)
		return s and (s:gsub("%W", function (c) return format("%%%02x", c:byte()); end));
	end
end

local _mkdir = {};
local function mkdir(path)
	path = path:gsub("/", path_separator); -- TODO as an optimization, do this during path creation rather than here
	if not _mkdir[path] then
		raw_mkdir(path);
		_mkdir[path] = true;
	end
	return path;
end

local data_path = (prosody and prosody.paths and prosody.paths.data) or ".";
local callbacks = {};

------- API -------------

function set_data_path(path)
	log("debug", "Setting data path to: %s", path);
	data_path = path;
end

local function callback(username, host, datastore, data)
	for _, f in ipairs(callbacks) do
		username, host, datastore, data = f(username, host, datastore, data);
		if username == false then break; end
	end

	return username, host, datastore, data;
end
function add_callback(func)
	if not callbacks[func] then -- Would you really want to set the same callback more than once?
		callbacks[func] = true;
		callbacks[#callbacks+1] = func;
		return true;
	end
end
function remove_callback(func)
	if callbacks[func] then
		for i, f in ipairs(callbacks) do
			if f == func then
				callbacks[i] = nil;
				callbacks[f] = nil;
				return true;
			end
		end
	end
end

function getpath(username, host, datastore, ext, create)
	ext = ext or "dat";
	host = (host and encode(host)) or "_global";
	username = username and encode(username);
	if username then
		if create then mkdir(mkdir(mkdir(data_path).."/"..host).."/"..datastore); end
		return format("%s/%s/%s/%s.%s", data_path, host, datastore, username, ext);
	elseif host then
		if create then mkdir(mkdir(data_path).."/"..host); end
		return format("%s/%s/%s.%s", data_path, host, datastore, ext);
	else
		if create then mkdir(data_path); end
		return format("%s/%s.%s", data_path, datastore, ext);
	end
end

function load(username, host, datastore)
	local data, ret = envloadfile(getpath(username, host, datastore), {});
	if not data then
		local mode = lfs.attributes(getpath(username, host, datastore), "mode");
		if not mode then
			log("debug", "Assuming empty %s storage ('%s') for user: %s@%s", datastore, ret, username or "nil", host or "nil");
			return nil;
		else -- file exists, but can't be read
			-- TODO more detailed error checking and logging?
			log("error", "Failed to load %s storage ('%s') for user: %s@%s", datastore, ret, username or "nil", host or "nil");
			return nil, "Error reading storage";
		end
	end

	local success, ret = pcall(data);
	if not success then
		log("error", "Unable to load %s storage ('%s') for user: %s@%s", datastore, ret, username or "nil", host or "nil");
		return nil, "Error reading storage";
	end
	return ret;
end

local function atomic_store(filename, data)
	local scratch = filename.."~";
	local f, ok, msg;
	repeat
		f, msg = io_open(scratch, "w");
		if not f then break end

		ok, msg = f:write(data);
		if not ok then break end

		ok, msg = f:close();
		if not ok then break end

		return os_rename(scratch, filename);
	until false;

	-- Cleanup
	if f then f:close(); end
	os_remove(scratch);
	return nil, msg;
end

if prosody.platform ~= "posix" then
	-- os.rename does not overwrite existing files on Windows
	-- TODO We could use Transactional NTFS on Vista and above
	function atomic_store(filename, data)
		local f, err = io_open(filename, "w");
		if not f then return f, err; end
		local ok, msg = f:write(data);
		if not ok then f:close(); return ok, msg; end
		return f:close();
	end
end

function store(username, host, datastore, data)
	if not data then
		data = {};
	end

	username, host, datastore, data = callback(username, host, datastore, data);
	if username == false then
		return true; -- Don't save this data at all
	end

	-- save the datastore
	local d = "return " .. serialize(data) .. ";\n";
	local ok, msg = atomic_store(getpath(username, host, datastore, nil, true), d);
	if not ok then
		log("error", "Unable to write to %s storage ('%s') for user: %s@%s", datastore, msg, username or "nil", host or "nil");
		return nil, "Error saving to storage";
	end
	if next(data) == nil then -- try to delete empty datastore
		log("debug", "Removing empty %s datastore for user %s@%s", datastore, username or "nil", host or "nil");
		os_remove(getpath(username, host, datastore));
	end
	-- we write data even when we are deleting because lua doesn't have a
	-- platform independent way of checking for non-exisitng files
	return true;
end

function list_append(username, host, datastore, data)
	if not data then return; end
	if callback(username, host, datastore) == false then return true; end
	-- save the datastore
	local f, msg = io_open(getpath(username, host, datastore, "list", true), "r+");
	if not f then
		f, msg = io_open(getpath(username, host, datastore, "list", true), "w");
	end
	if not f then
		log("error", "Unable to write to %s storage ('%s') for user: %s@%s", datastore, msg, username or "nil", host or "nil");
		return;
	end
	local data = "item(" ..  serialize(data) .. ");\n";
	local pos = f:seek("end");
	local ok, msg = fallocate(f, pos, #data);
	f:seek("set", pos);
	if ok then
		f:write(data);
	else
		log("error", "Unable to write to %s storage ('%s') for user: %s@%s", datastore, msg, username or "nil", host or "nil");
		return ok, msg;
	end
	f:close();
	return true;
end

function list_store(username, host, datastore, data)
	if not data then
		data = {};
	end
	if callback(username, host, datastore) == false then return true; end
	-- save the datastore
	local d = {};
	for _, item in ipairs(data) do
		d[#d+1] = "item(" .. serialize(item) .. ");\n";
	end
	local ok, msg = atomic_store(getpath(username, host, datastore, "list", true), t_concat(d));
	if not ok then
		log("error", "Unable to write to %s storage ('%s') for user: %s@%s", datastore, msg, username or "nil", host or "nil");
		return;
	end
	if next(data) == nil then -- try to delete empty datastore
		log("debug", "Removing empty %s datastore for user %s@%s", datastore, username or "nil", host or "nil");
		os_remove(getpath(username, host, datastore, "list"));
	end
	-- we write data even when we are deleting because lua doesn't have a
	-- platform independent way of checking for non-exisitng files
	return true;
end

function list_load(username, host, datastore)
	local items = {};
	local data, ret = envloadfile(getpath(username, host, datastore, "list"), {item = function(i) t_insert(items, i); end});
	if not data then
		local mode = lfs.attributes(getpath(username, host, datastore, "list"), "mode");
		if not mode then
			log("debug", "Assuming empty %s storage ('%s') for user: %s@%s", datastore, ret, username or "nil", host or "nil");
			return nil;
		else -- file exists, but can't be read
			-- TODO more detailed error checking and logging?
			log("error", "Failed to load %s storage ('%s') for user: %s@%s", datastore, ret, username or "nil", host or "nil");
			return nil, "Error reading storage";
		end
	end

	local success, ret = pcall(data);
	if not success then
		log("error", "Unable to load %s storage ('%s') for user: %s@%s", datastore, ret, username or "nil", host or "nil");
		return nil, "Error reading storage";
	end
	return items;
end

local type_map = {
	keyval = "dat";
	list = "list";
}

function stores(username, host, typ)
	typ = type_map[typ or "keyval"];
	local store_dir = format("%s/%s/", data_path, encode(host));

	local mode, err = lfs.attributes(store_dir, "mode");
	if not mode then
		return function() log("debug", err or (store_dir .. " does not exist")) end
	end
	local next, state = lfs.dir(store_dir);
	return function(state)
		for node in next, state do
			if not node:match"^%." then
				if username == true then
					if lfs.attributes(store_dir..node, "mode") == "directory" then
						return decode(node);
					end
				elseif username then
					local store = decode(node)
					if lfs.attributes(getpath(username, host, store, typ), "mode") then
						return store;
					end
				elseif lfs.attributes(node, "mode") == "file" then
					local file, ext = node:match("^(.*)%.([dalist]+)$");
					if ext == typ then
						return decode(file)
					end
				end
			end
		end
	end, state;
end

local function do_remove(path)
	local ok, err = os_remove(path);
	if not ok and lfs.attributes(path, "mode") then
		return ok, err;
	end
	return true
end

function purge(username, host)
	local host_dir = format("%s/%s/", data_path, encode(host));
	local deleted = 0;
	local errs = {};
	for file in lfs.dir(host_dir) do
		if lfs.attributes(host_dir..file, "mode") == "directory" then
			local store = decode(file);
			local ok, err = do_remove(getpath(username, host, store));
			if not ok then errs[#errs+1] = err; end

			local ok, err = do_remove(getpath(username, host, store, "list"));
			if not ok then errs[#errs+1] = err; end
		end
	end
	return #errs == 0, t_concat(errs, ", ");
end

return _M;