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 use Wikimedia\AtEase\AtEase;
  28
  29 /**
  30  * This class is used to hold the location and do limited manipulation
  31  * of files stored temporarily (this will be whatever wfTempDir() returns)
  32  *
  33  * @ingroup FileBackend
  34  */
  35 class TempFSFile extends FSFile {
  36         /** @var bool Garbage collect the temp file */
  37         protected $canDelete = false;
  38
  39         /** @var array Map of (path => 1) for paths to delete on shutdown */
  40         protected static $pathsCollect = null;
  41
  42         /**
  43          * Do not call directly. Use TempFSFileFactory
  44          *
  45          * @param string $path
  46          */
  47         public function __construct( $path ) {
  48                 parent::__construct( $path );
  49
  50                 if ( self::$pathsCollect === null ) {
  51                         // @codeCoverageIgnoreStart
  52                         self::$pathsCollect = [];
  53                         register_shutdown_function( [ __CLASS__, 'purgeAllOnShutdown' ] );
  54                         // @codeCoverageIgnoreEnd
  55                 }
  56         }
  57
  58         /**
  59          * Make a new temporary file on the file system.
  60          * Temporary files may be purged when the file object falls out of scope.
  61          *
  62          * @deprecated since 1.34, use TempFSFileFactory directly
  63          *
  64          * @param string $prefix
  65          * @param string $extension Optional file extension
  66          * @param string|null $tmpDirectory Optional parent directory
  67          * @return TempFSFile|null
  68          */
  69         public static function factory( $prefix, $extension = '', $tmpDirectory = null ) {
  70                 return ( new TempFSFileFactory( $tmpDirectory ) )->newTempFSFile( $prefix, $extension );
  71         }
  72
  73         /**
  74          * @todo Is there any useful way to test this? Would it be useful to make this non-static on
  75          * TempFSFileFactory?
  76          *
  77          * @return string Filesystem path to a temporary directory
  78          * @throws RuntimeException if no writable temporary directory can be found
  79          */
  80         public static function getUsableTempDirectory() {
  81                 $tmpDir = array_map( 'getenv', [ 'TMPDIR', 'TMP', 'TEMP' ] );
  82                 $tmpDir[] = sys_get_temp_dir();
  83                 $tmpDir[] = ini_get( 'upload_tmp_dir' );
  84                 foreach ( $tmpDir as $tmp ) {
  85                         if ( $tmp != '' && is_dir( $tmp ) && is_writable( $tmp ) ) {
  86                                 return $tmp;
  87                         }
  88                 }
  89
  90                 // PHP on Windows will detect C:\Windows\Temp as not writable even though PHP can write to
  91                 // it so create a directory within that called 'mwtmp' with a suffix of the user running
  92                 // the current process.
  93                 // The user is included as if various scripts are run by different users they will likely
  94                 // not be able to access each others temporary files.
  95                 if ( strtoupper( substr( PHP_OS, 0, 3 ) ) === 'WIN' ) {
  96                         $tmp = sys_get_temp_dir() . DIRECTORY_SEPARATOR . 'mwtmp-' . get_current_user();
  97                         if ( !file_exists( $tmp ) ) {
  98                                 mkdir( $tmp );
  99                         }
 100                         if ( is_dir( $tmp ) && is_writable( $tmp ) ) {
 101                                 return $tmp;
 102                         }
 103                 }
 104
 105                 throw new RuntimeException(
 106                         'No writable temporary directory could be found. ' .
 107                         'Please explicitly specify a writable directory in configuration.' );
 108         }
 109
 110         /**
 111          * Purge this file off the file system
 112          *
 113          * @return bool Success
 114          */
 115         public function purge() {
 116                 $this->canDelete = false; // done
 117                 AtEase::suppressWarnings();
 118                 $ok = unlink( $this->path );
 119                 AtEase::restoreWarnings();
 120
 121                 unset( self::$pathsCollect[$this->path] );
 122
 123                 return $ok;
 124         }
 125
 126         /**
 127          * Clean up the temporary file only after an object goes out of scope
 128          *
 129          * @param object $object
 130          * @return TempFSFile This object
 131          */
 132         public function bind( $object ) {
 133                 if ( is_object( $object ) ) {
 134                         if ( !isset( $object->tempFSFileReferences ) ) {
 135                                 // Init first since $object might use __get() and return only a copy variable
 136                                 $object->tempFSFileReferences = [];
 137                         }
 138                         $object->tempFSFileReferences[] = $this;
 139                 }
 140
 141                 return $this;
 142         }
 143
 144         /**
 145          * Set flag to not clean up after the temporary file
 146          *
 147          * @return TempFSFile This object
 148          */
 149         public function preserve() {
 150                 $this->canDelete = false;
 151
 152                 unset( self::$pathsCollect[$this->path] );
 153
 154                 return $this;
 155         }
 156
 157         /**
 158          * Set flag clean up after the temporary file
 159          *
 160          * @return TempFSFile This object
 161          */
 162         public function autocollect() {
 163                 $this->canDelete = true;
 164
 165                 self::$pathsCollect[$this->path] = 1;
 166
 167                 return $this;
 168         }
 169
 170         /**
 171          * Try to make sure that all files are purged on error
 172          *
 173          * This method should only be called internally
 174          *
 175          * @codeCoverageIgnore
 176          */
 177         public static function purgeAllOnShutdown() {
 178                 foreach ( self::$pathsCollect as $path => $unused ) {
 179                         AtEase::suppressWarnings();
 180                         unlink( $path );
 181                         AtEase::restoreWarnings();
 182                 }
 183         }
 184
 185         /**
 186          * Cleans up after the temporary file by deleting it
 187          */
 188         function __destruct() {
 189                 if ( $this->canDelete ) {
 190                         $this->purge();
 191                 }
 192         }
 193 }