mirrors/prosody
1
0
Fork 0
mirror of https://github.com/bjc/prosody.git synced 2025-04-04 05:37:39 +03:00
Code Issues Projects Releases Packages Wiki Activity Actions

util.datamanager: Use pposix.atomic_append

Browse source
This commit is contained in:
Kim Alvefur 2017-02-28 11:33:43 +01:00
parent e8b57d789b
commit 7b4ad0e694
1 changed files with 17 additions and 23 deletions
Download patch file Download diff file Expand all files Collapse all files

40
util/datamanager.lua
View file

@ -17,7 +17,6 @@ local io_open = io.open;
local os_remove = os.remove;
local os_rename = os.rename;
local tonumber = tonumber;
local tostring = tostring;
local next = next;
local type = type;
local t_insert = table.insert;
@ -31,21 +30,12 @@ local path_separator = assert ( package.config:match ( "^([^\n]+)" ) , "package.
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;
local atomic_append;
local ENOENT = 2;
pcall(function()
local pposix = require "util.pposix";
raw_mkdir = pposix.mkdir or raw_mkdir; -- Doesn't trample on umask
fallocate = pposix.fallocate or fallocate;
atomic_append = pposix.atomic_append;
ENOENT = pposix.ENOENT or ENOENT;
end);
@ -65,6 +55,19 @@ do
end
end
if not atomic_append then
function atomic_append(f, data)
local pos = f:seek();
if not f:write(data) or not f:flush() then
f:seek("set", pos);
f:write((" "):rep(#data));
f:flush();
return nil, "write-failed";
end
return true;
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
@ -221,25 +224,16 @@ local function append(username, host, datastore, ext, data)
local filename = getpath(username, host, datastore, ext, true);
local ok;
local f, msg = io_open(filename, "r+");
local f, msg, errno = io_open(filename, "r+");
if not f then
return atomic_store(filename, data);
-- File did probably not exist, let's create it
end
local pos = f:seek("end");
ok, msg = fallocate(f, pos, #data);
if not ok then
log("warn", "fallocate() failed: %s", tostring(msg));
-- This doesn't work on every file system
end
if f:seek() ~= pos then
log("debug", "fallocate() changed file position");
f:seek("set", pos);
end
ok, msg = atomic_append(f, data);
ok, msg = f:write(data);
if not ok then
f:close();
return ok, msg, "write";