includes/libs/filebackend/fsfile/TempFSFile.php

   1 <?php
   2
   3 use MediaWiki\FileBackend\FSFile\TempFSFileFactory;
   4
   5 /**
   6  * Location holder of files stored temporarily
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 2 of the License, or
  11  * (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License along
  19  * with this program; if not, write to the Free Software Foundation, Inc.,
  20  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  21  * http://www.gnu.org/copyleft/gpl.html
  22  *
  23  * @file
  24  * @ingroup FileBackend
  25  */
  26
  27 /**
  28  * This class is used to hold the location and do limited manipulation
  29  * of files stored temporarily (this will be whatever wfTempDir() returns)
  30  *
  31  * @ingroup FileBackend
  32  */
  33 class TempFSFile extends FSFile {
  34         /** @var bool Garbage collect the temp file */
  35         protected $canDelete = false;
  36
  37         /** @var array Map of (path => 1) for paths to delete on shutdown */
  38         protected static $pathsCollect = null;
  39
  40         /**
  41          * Do not call directly. Use TempFSFileFactory.
  42          */
  43         public function __construct( $path ) {
  44                 parent::__construct( $path );
  45
  46                 if ( self::$pathsCollect === null ) {
  47                         // @codeCoverageIgnoreStart
  48                         self::$pathsCollect = [];
  49                         register_shutdown_function( [ __CLASS__, 'purgeAllOnShutdown' ] );
  50                         // @codeCoverageIgnoreEnd
  51                 }
  52         }
  53
  54         /**
  55          * Make a new temporary file on the file system.
  56          * Temporary files may be purged when the file object falls out of scope.
  57          *
  58          * @deprecated since 1.34, use TempFSFileFactory directly
  59          *
  60          * @param string $prefix
  61          * @param string $extension Optional file extension
  62          * @param string|null $tmpDirectory Optional parent directory
  63          * @return TempFSFile|null
  64          */
  65         public static function factory( $prefix, $extension = '', $tmpDirectory = null ) {
  66                 return ( new TempFSFileFactory( $tmpDirectory ) )->newTempFSFile( $prefix, $extension );
  67         }
  68
  69         /**
  70          * @todo Is there any useful way to test this? Would it be useful to make this non-static on
  71          * TempFSFileFactory?
  72          *
  73          * @return string Filesystem path to a temporary directory
  74          * @throws RuntimeException if no writable temporary directory can be found
  75          */
  76         public static function getUsableTempDirectory() {
  77                 $tmpDir = array_map( 'getenv', [ 'TMPDIR', 'TMP', 'TEMP' ] );
  78                 $tmpDir[] = sys_get_temp_dir();
  79                 $tmpDir[] = ini_get( 'upload_tmp_dir' );
  80                 foreach ( $tmpDir as $tmp ) {
  81                         if ( $tmp != '' && is_dir( $tmp ) && is_writable( $tmp ) ) {
  82                                 return $tmp;
  83                         }
  84                 }
  85
  86                 // PHP on Windows will detect C:\Windows\Temp as not writable even though PHP can write to
  87                 // it so create a directory within that called 'mwtmp' with a suffix of the user running
  88                 // the current process.
  89                 // The user is included as if various scripts are run by different users they will likely
  90                 // not be able to access each others temporary files.
  91                 if ( strtoupper( substr( PHP_OS, 0, 3 ) ) === 'WIN' ) {
  92                         $tmp = sys_get_temp_dir() . DIRECTORY_SEPARATOR . 'mwtmp-' . get_current_user();
  93                         if ( !file_exists( $tmp ) ) {
  94                                 mkdir( $tmp );
  95                         }
  96                         if ( is_dir( $tmp ) && is_writable( $tmp ) ) {
  97                                 return $tmp;
  98                         }
  99                 }
 100
 101                 throw new RuntimeException(
 102                         'No writable temporary directory could be found. ' .
 103                         'Please explicitly specify a writable directory in configuration.' );
 104         }
 105
 106         /**
 107          * Purge this file off the file system
 108          *
 109          * @return bool Success
 110          */
 111         public function purge() {
 112                 $this->canDelete = false; // done
 113                 Wikimedia\suppressWarnings();
 114                 $ok = unlink( $this->path );
 115                 Wikimedia\restoreWarnings();
 116
 117                 unset( self::$pathsCollect[$this->path] );
 118
 119                 return $ok;
 120         }
 121
 122         /**
 123          * Clean up the temporary file only after an object goes out of scope
 124          *
 125          * @param object $object
 126          * @return TempFSFile This object
 127          */
 128         public function bind( $object ) {
 129                 if ( is_object( $object ) ) {
 130                         if ( !isset( $object->tempFSFileReferences ) ) {
 131                                 // Init first since $object might use __get() and return only a copy variable
 132                                 $object->tempFSFileReferences = [];
 133                         }
 134                         $object->tempFSFileReferences[] = $this;
 135                 }
 136
 137                 return $this;
 138         }
 139
 140         /**
 141          * Set flag to not clean up after the temporary file
 142          *
 143          * @return TempFSFile This object
 144          */
 145         public function preserve() {
 146                 $this->canDelete = false;
 147
 148                 unset( self::$pathsCollect[$this->path] );
 149
 150                 return $this;
 151         }
 152
 153         /**
 154          * Set flag clean up after the temporary file
 155          *
 156          * @return TempFSFile This object
 157          */
 158         public function autocollect() {
 159                 $this->canDelete = true;
 160
 161                 self::$pathsCollect[$this->path] = 1;
 162
 163                 return $this;
 164         }
 165
 166         /**
 167          * Try to make sure that all files are purged on error
 168          *
 169          * This method should only be called internally
 170          *
 171          * @codeCoverageIgnore
 172          */
 173         public static function purgeAllOnShutdown() {
 174                 foreach ( self::$pathsCollect as $path => $unused ) {
 175                         Wikimedia\suppressWarnings();
 176                         unlink( $path );
 177                         Wikimedia\restoreWarnings();
 178                 }
 179         }
 180
 181         /**
 182          * Cleans up after the temporary file by deleting it
 183          */
 184         function __destruct() {
 185                 if ( $this->canDelete ) {
 186                         $this->purge();
 187                 }
 188         }
 189 }