Software /
code /
prosody
Changeset
8011:f8ba814fe029
util.datamanager: Use pposix.atomic_append
author | Kim Alvefur <zash@zash.se> |
---|---|
date | Tue, 28 Feb 2017 11:33:43 +0100 (2017-02-28) |
parents | 8010:49feb0da29e1 |
children | 8012:e898c8fda986 |
files | util/datamanager.lua |
diffstat | 1 files changed, 17 insertions(+), 23 deletions(-) [+] |
line wrap: on
line diff
--- a/util/datamanager.lua Wed Mar 01 01:33:00 2017 +0100 +++ b/util/datamanager.lua Tue Feb 28 11:33:43 2017 +0100 @@ -17,7 +17,6 @@ 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 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 @@ 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 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";