Commit 220c6c9e authored by catch's avatar catch
Browse files

Issue #3211936 by alexpott, daffie: Race condition when generating sub directories for image styles 

(cherry picked from commit 2690c63d)
parent 9fc59b1e

core/lib/Drupal/Core/File/FileSystem.php

+4 −1
Original line number Diff line number Diff line
@@ -214,7 +214,10 @@ public function mkdir($uri, $mode = NULL, $recursive = FALSE, $context = NULL) { 
        $recursive_path .= $component;



        if (!file_exists($recursive_path)) {

          if (!$this->mkdirCall($recursive_path, $mode, FALSE, $context)) {

          $success = $this->mkdirCall($recursive_path, $mode, FALSE, $context);

          // If the operation failed, check again if the directory was created

          // by another process/server, only report a failure if not.

          if (!$success && !file_exists($recursive_path)) {

            return FALSE;

          }

          // Not necessary to use self::chmod() as there is no scheme.

core/tests/Drupal/KernelTests/Core/File/DirectoryTest.php

+48 −0
Original line number Diff line number Diff line
@@ -5,6 +5,7 @@ 
use Drupal\Component\FileSecurity\FileSecurity;

use Drupal\Component\FileSystem\FileSystem;

use Drupal\Component\Render\FormattableMarkup;

use Drupal\Core\Database\Database;

use Drupal\Core\File\Exception\FileException;

use Drupal\Core\File\FileSystemInterface;
@@ -196,4 +197,51 @@ public function testDirectoryCreation() { 
    $this->assertTrue($file_system->mkdir($dir . '/foo/baz/', 0775, TRUE));

  }



  /**

   * Tests asynchronous directory creation.

   *

   * Image style generation can result in many calls to create similar directory

   * paths. This test forks the process to create the same situation.

   */

  public function testMultiplePrepareDirectory() {

    if (!function_exists('pcntl_fork')) {

      $this->markTestSkipped('Requires the pcntl_fork() function');

    }

    $directories = [];

    for ($i = 1; $i <= 10; $i++) {

      $directories[] = 'public://a/b/c/d/e/f/g/h/' . $i;

    }



    $file_system = $this->container->get('file_system');



    $time_to_start = microtime(TRUE) + 0.1;

    // This loop creates a new fork to create each directory.

    foreach ($directories as $directory) {

      $pid = pcntl_fork();

      if ($pid == -1) {

        $this->fail("Error forking");

      }

      elseif ($pid == 0) {

        // Sleep so that all the forks start preparing the directory at the same

        // time.

        usleep(($time_to_start - microtime(TRUE)) * 1000000);

        $file_system->prepareDirectory($directory, FileSystemInterface::CREATE_DIRECTORY);

        exit();

      }

    }



    // This while loop holds the parent process until all the child threads

    // are complete - at which point the script continues to execute.

    while (pcntl_waitpid(0, $status) != -1);



    foreach ($directories as $directory) {

      $this->assertDirectoryExists($directory);

    }



    // Remove the database connection because it will have been destroyed when

    // the forks exited. This allows

    // \Drupal\KernelTests\KernelTestBase::tearDown() to reopen it.

    Database::removeConnection('default');

  }



}