includes/filerepo/file/TempFSFile.php

   1 <?php
   2 /**
   3  * @file
   4  * @ingroup FileRepo
   5  * @ingroup FileBackend
   6  */
   7
   8 /**
   9  * This class is used to hold the location and do limited manipulation
  10  * of files stored temporarily (usually this will be $wgTmpDirectory)
  11  *
  12  * @ingroup FileRepo
  13  * @ingroup FileBackend
  14  */
  15 class TempFSFile extends FSFile {
  16         protected $canDelete = true; // garbage collect the temp file
  17
  18         /** @var Array of active temp files to purge on shutdown */
  19         protected static $instances = array();
  20
  21         /**
  22          * Make a new temporary file on the file system.
  23          * Temporary files may be purged when the file object falls out of scope.
  24          *
  25          * @param $prefix string
  26          * @param $extension string
  27          * @return TempFSFile|null
  28          */
  29         public static function factory( $prefix, $extension = '' ) {
  30                 $base = wfTempDir() . '/' . $prefix . dechex( mt_rand( 0, 99999999 ) );
  31                 $ext = ( $extension != '' ) ? ".{$extension}" : "";
  32                 for ( $attempt = 1; true; $attempt++ ) {
  33                         $path = "{$base}-{$attempt}{$ext}";
  34                         wfSuppressWarnings();
  35                         $newFileHandle = fopen( $path, 'x' );
  36                         wfRestoreWarnings();
  37                         if ( $newFileHandle ) {
  38                                 fclose( $newFileHandle );
  39                                 break; // got it
  40                         }
  41                         if ( $attempt >= 15 ) {
  42                                 return null; // give up
  43                         }
  44                 }
  45                 $tmpFile = new self( $path );
  46                 if ( php_sapi_name() != 'cli' ) {
  47                         self::$instances[] = $tmpFile; // defer purge till shutdown
  48                 }
  49                 return $tmpFile;
  50         }
  51
  52         /**
  53          * Purge this file off the file system
  54          *
  55          * @return bool Success
  56          */
  57         public function purge() {
  58                 $this->canDelete = false; // done
  59                 wfSuppressWarnings();
  60                 $ok = unlink( $this->path );
  61                 wfRestoreWarnings();
  62                 return $ok;
  63         }
  64
  65         /**
  66          * Clean up the temporary file only after an object goes out of scope
  67          *
  68          * @param $object Object
  69          * @return void
  70          */
  71         public function bind( $object ) {
  72                 if ( is_object( $object ) ) {
  73                         $object->tempFSFileReferences[] = $this;
  74                 }
  75         }
  76
  77         /**
  78          * Set flag to not clean up after the temporary file
  79          *
  80          * @return void
  81          */
  82         public function preserve() {
  83                 $this->canDelete = false;
  84         }
  85
  86         /**
  87          * Cleans up after the temporary file by deleting it
  88          */
  89         function __destruct() {
  90                 if ( $this->canDelete ) {
  91                         wfSuppressWarnings();
  92                         unlink( $this->path );
  93                         wfRestoreWarnings();
  94                 }
  95         }
  96 }