includes/filerepo/backend/TempFSFile.php

   1 <?php
   2 /**
   3  * @file
   4  * @ingroup FileBackend
   5  */
   6
   7 /**
   8  * This class is used to hold the location and do limited manipulation
   9  * of files stored temporarily (usually this will be $wgTmpDirectory)
  10  *
  11  * @ingroup FileBackend
  12  */
  13 class TempFSFile extends FSFile {
  14         protected $canDelete = false; // bool; garbage collect the temp file
  15
  16         /** @var Array of active temp files to purge on shutdown */
  17         protected static $instances = array();
  18
  19         /**
  20          * Make a new temporary file on the file system.
  21          * Temporary files may be purged when the file object falls out of scope.
  22          *
  23          * @param $prefix string
  24          * @param $extension string
  25          * @return TempFSFile|null
  26          */
  27         public static function factory( $prefix, $extension = '' ) {
  28                 $base = wfTempDir() . '/' . $prefix . dechex( mt_rand( 0, 99999999 ) );
  29                 $ext = ( $extension != '' ) ? ".{$extension}" : "";
  30                 for ( $attempt = 1; true; $attempt++ ) {
  31                         $path = "{$base}-{$attempt}{$ext}";
  32                         wfSuppressWarnings();
  33                         $newFileHandle = fopen( $path, 'x' );
  34                         wfRestoreWarnings();
  35                         if ( $newFileHandle ) {
  36                                 fclose( $newFileHandle );
  37                                 break; // got it
  38                         }
  39                         if ( $attempt >= 15 ) {
  40                                 return null; // give up
  41                         }
  42                 }
  43                 $tmpFile = new self( $path );
  44                 $tmpFile->canDelete = true; // safely instantiated
  45                 return $tmpFile;
  46         }
  47
  48         /**
  49          * Purge this file off the file system
  50          *
  51          * @return bool Success
  52          */
  53         public function purge() {
  54                 $this->canDelete = false; // done
  55                 wfSuppressWarnings();
  56                 $ok = unlink( $this->path );
  57                 wfRestoreWarnings();
  58                 return $ok;
  59         }
  60
  61         /**
  62          * Clean up the temporary file only after an object goes out of scope
  63          *
  64          * @param $object Object
  65          * @return void
  66          */
  67         public function bind( $object ) {
  68                 if ( is_object( $object ) ) {
  69                         $object->tempFSFileReferences[] = $this;
  70                 }
  71         }
  72
  73         /**
  74          * Set flag to not clean up after the temporary file
  75          *
  76          * @return void
  77          */
  78         public function preserve() {
  79                 $this->canDelete = false;
  80         }
  81
  82         /**
  83          * Cleans up after the temporary file by deleting it
  84          */
  85         function __destruct() {
  86                 if ( $this->canDelete ) {
  87                         wfSuppressWarnings();
  88                         unlink( $this->path );
  89                         wfRestoreWarnings();
  90                 }
  91         }
  92 }