diff options
| -rw-r--r-- | inc/io.php | 45 |
1 files changed, 45 insertions, 0 deletions
diff --git a/inc/io.php b/inc/io.php index a3e5f85c4..4e6faefa8 100644 --- a/inc/io.php +++ b/inc/io.php @@ -57,6 +57,7 @@ function io_readFile($file){ */ function io_saveFile($file,$content){ io_makeFileDir($file); + io_lock($file); if(substr($file,-3) == '.gz'){ $fh = @gzopen($file,'wb9'); if(!$fh){ @@ -74,10 +75,54 @@ function io_saveFile($file,$content){ fwrite($fh, $content); fclose($fh); } + io_unlock($file); return true; } /** + * Tries to lock a file + * + * Locking is only done for io_savefile and uses directories + * inside $conf['lockdir'] + * + * It waits maximal 3 seconds for the lock, after this time + * the lock is assumed to be stale and the function goes on + * + * @author Andreas Gohr <andi@splitbrain.org> + */ +function io_lock($file){ + global $conf; + // no locking if safemode hack + if($conf['safemodehack']) return; + + $lockDir = $conf['lockdir'].'/'.md5($file); + @ignore_user_abort(1); + + + $timeStart = time(); + do { + //waited longer than 3 seconds? -> stale lock + if ((time() - $timeStart) > 3) break; + $locked = @mkdir($lockDir); + } while ($locked === false); +} + +/** + * Unlocks a file + * + * @author Andreas Gohr <andi@splitbrain.org> + */ +function io_unlock($file){ + global $conf; + // no locking if safemode hack + if($conf['safemodehack']) return; + + $lockDir = $conf['lockdir'].'/'.md5($file); + @rmdir($lockDir); + @ignore_user_abort(0); +} + +/** * Create the directory needed for the given file * * @author Andreas Gohr <andi@splitbrain.org> |