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 = true; // 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( $path );
  44                 if ( php_sapi_name() != 'cli' ) {
  45                         self::$instances[] = $tmpFile; // defer purge till shutdown
  46                 }
  47                 return $tmpFile;
  48         }
  49
  50         /**
  51          * Purge this file off the file system
  52          *
  53          * @return bool Success
  54          */
  55         public function purge() {
  56                 $this->canDelete = false; // done
  57                 wfSuppressWarnings();
  58                 $ok = unlink( $this->path );
  59                 wfRestoreWarnings();
  60                 return $ok;
  61         }
  62
  63         /**
  64          * Clean up the temporary file only after an object goes out of scope
  65          *
  66          * @param $object Object
  67          * @return void
  68          */
  69         public function bind( $object ) {
  70                 if ( is_object( $object ) ) {
  71                         $object->tempFSFileReferences[] = $this;
  72                 }
  73         }
  74
  75         /**
  76          * Set flag to not clean up after the temporary file
  77          *
  78          * @return void
  79          */
  80         public function preserve() {
  81                 $this->canDelete = false;
  82         }
  83
  84         /**
  85          * Cleans up after the temporary file by deleting it
  86          */
  87         function __destruct() {
  88                 if ( $this->canDelete ) {
  89                         wfSuppressWarnings();
  90                         unlink( $this->path );
  91                         wfRestoreWarnings();
  92                 }
  93         }
  94 }