file_resup.module in File Resumable Upload 8

File

file_resup.module

<?php

/**
 * @file
 * Written by Henri MEDOT <henri.medot[AT]absyx[DOT]fr>
 * http://www.absyx.fr
 */
require_once dirname(__FILE__) . '/file_resup.field.inc';
define('FILE_RESUP_DEFAULT_CHUNKSIZE', 2 * 1024 * 1024);
define('FILE_RESUP_TEMPORARY', 'file_resup_temporary');

/**
 * Implements hook_permission().
 */
function file_resup_permission() {
  return array(
    'upload via file_resup' => array(
      'title' => t('Upload via <em>File Resumable Upload</em>'),
    ),
  );
}

/**
 * Implements hook_menu().
 */
function file_resup_menu() {
  $items['file_resup/upload'] = array(
    'page callback' => 'file_resup_upload',
    'access arguments' => array(
      'upload via file_resup',
    ),
    'type' => MENU_CALLBACK,
  );
  return $items;
}

/**
 * Menu callback to upload a file chunk.
 */
function file_resup_upload() {

  // Get the form build ID.
  $form_parents = func_get_args();
  $form_build_id = (string) array_pop($form_parents);
  if (empty($_REQUEST['form_build_id']) || $form_build_id != $_REQUEST['form_build_id']) {
    drupal_exit();
  }

  // Get a valid upload ID.
  if (empty($_REQUEST['resup_file_id']) || !($upload_id = file_resup_upload_id($_REQUEST['resup_file_id']))) {
    drupal_exit();
  }

  // On method GET...
  if ($_SERVER['REQUEST_METHOD'] == 'GET') {

    // Attempt to find a record for the upload.
    $upload = file_resup_upload_load($upload_id);

    // If found, return how many chunks were uploaded so far.
    if ($upload) {
      return file_resup_plain_output($upload->uploaded_chunks);
    }

    // If not, prepare a new upload.
    // Get the form.
    $_POST['form_build_id'] = $form_build_id;
    list($form) = ajax_get_form();

    // Get the form element.
    $element = drupal_array_get_nested_value($form, $form_parents);
    if (!$element) {
      drupal_exit();
    }

    // Retrieve the file name and size.
    if (empty($_GET['resup_file_name']) || empty($_GET['resup_file_size'])) {
      drupal_exit();
    }
    $filename = $_GET['resup_file_name'];
    $filesize = $_GET['resup_file_size'];

    // Validate the file name length.
    if (strlen($filename) > 240) {
      drupal_exit();
    }

    // Validate the file extension.
    if (isset($element['#file_resup_upload_validators']['file_validate_extensions'][0])) {
      $regex = '/\\.(?:' . preg_replace('/ +/', '|', preg_quote($element['#file_resup_upload_validators']['file_validate_extensions'][0])) . ')$/i';
      if (!preg_match($regex, $filename)) {
        drupal_exit();
      }
    }

    // Validate the file size.
    if (!preg_match('`^[1-9]\\d*$`', $filesize) || $filesize > $element['#file_resup_upload_validators']['file_validate_size'][0]) {
      drupal_exit();
    }

    // Retrieve the upload location scheme from the form element.
    $scheme = file_uri_scheme($element['#upload_location']);
    if (!$scheme || !file_stream_wrapper_valid_scheme($scheme)) {
      drupal_exit();
    }

    // Prepare the file_resup_temporary private directory.
    $directory = $scheme . '://' . FILE_RESUP_TEMPORARY;
    if (!file_prepare_directory($directory, FILE_CREATE_DIRECTORY)) {
      drupal_exit();
    }
    file_create_htaccess($directory, TRUE);

    // Insert a new upload record.
    $upload = new stdClass();
    $upload->upload_id = $upload_id;
    $upload->filename = $filename;
    $upload->filesize = $filesize;
    $upload->scheme = $scheme;
    $upload->timestamp = time();
    try {
      if (!drupal_write_record('file_resup', $upload)) {
        drupal_exit();
      }
    } catch (Exception $e) {
      drupal_exit();
    }

    // No upload file should exist at this point.
    file_resup_upload_delete_file($upload);

    // Return 0 as the number of uploaded chunks.
    return file_resup_plain_output('0');
  }

  // On method POST...
  // Ensure we have a valid uploaded file.
  if (empty($_FILES['resup_chunk'])) {
    drupal_exit();
  }
  $file = $_FILES['resup_chunk'];
  if ($file['error'] != UPLOAD_ERR_OK || !is_uploaded_file($file['tmp_name']) || !$file['size'] || $file['size'] > file_resup_chunksize()) {
    drupal_exit();
  }

  // Validate the format of the chunk number.
  if (empty($_POST['resup_chunk_number']) || !preg_match('`^[1-9]\\d*$`', $_POST['resup_chunk_number'])) {
    drupal_exit();
  }
  $chunk_number = (int) $_POST['resup_chunk_number'];

  // Get the upload record.
  $upload = file_resup_upload_load($upload_id);

  // If no record was found, return nothing.
  if (!$upload) {
    drupal_exit();
  }

  // Validate the chunk number.
  if ($chunk_number > ceil($upload->filesize / file_resup_chunksize())) {
    drupal_exit();
  }

  // If we were given an unexpected chunk number, return what we expected.
  if ($chunk_number != $upload->uploaded_chunks + 1) {
    return file_resup_plain_output($upload->uploaded_chunks);
  }

  // Open the upload file.
  $fp = @fopen(file_resup_upload_uri($upload), 'ab');
  if (!$fp) {
    drupal_exit();
  }

  // Acquire an exclusive lock.
  if (!flock($fp, LOCK_EX)) {
    fclose($fp);
    drupal_exit();
  }

  // Update the record and append the chunk.
  $transaction = db_transaction();
  try {
    $affected = db_update('file_resup')
      ->fields(array(
      'uploaded_chunks' => $chunk_number,
      'timestamp' => time(),
    ))
      ->condition('upload_id', $upload_id)
      ->condition('uploaded_chunks', $chunk_number - 1)
      ->execute();
    if (!$affected || ($contents = file_get_contents($file['tmp_name'])) === FALSE || !fwrite($fp, $contents)) {
      throw new Exception();
    }
  } catch (Exception $e) {
    $transaction
      ->rollback();
    flock($fp, LOCK_UN);
    fclose($fp);
    drupal_exit();
  }

  // Commit the transaction.
  unset($transaction);

  // Flush the output then unlock and close the file.
  fflush($fp);
  flock($fp, LOCK_UN);
  fclose($fp);

  // Return the updated number of uploaded chunks.
  file_resup_plain_output($chunk_number);
}

/**
 * Returns data as plain text.
 */
function file_resup_plain_output($text = '') {
  drupal_page_is_cacheable(FALSE);
  drupal_add_http_header('Content-Type', 'text/plain');
  echo $text;
}

/**
 * Save a completed upload.
 */
function file_resup_save_upload($element, $resup_file_id) {
  global $user;

  // Get a valid upload ID.
  $upload_id = file_resup_upload_id($resup_file_id);
  if (!$upload_id) {
    return FALSE;
  }

  // Get the upload record.
  $upload = file_resup_upload_load($upload_id);
  if (!$upload) {
    return FALSE;
  }

  // The file may have already been uploaded before.
  if ($upload->fid) {
    return file_load($upload->fid);
  }

  // Ensure the upload is complete.
  if ($upload->uploaded_chunks != ceil($upload->filesize / file_resup_chunksize())) {
    return FALSE;
  }

  // Ensure the destination is still valid.
  $destination = $element['#upload_location'];
  $destination_scheme = file_uri_scheme($destination);
  if (!$destination_scheme || $destination_scheme != $upload->scheme) {
    return FALSE;
  }

  // Ensure the uploaded file is present.
  $upload_uri = file_resup_upload_uri($upload);
  if (!file_exists($upload_uri)) {
    return FALSE;
  }

  // Begin building the file object.
  $file = new stdClass();
  $file->uid = $user->uid;
  $file->status = 0;
  $file->filename = trim(drupal_basename($upload->filename), '.');
  $file->uri = $upload_uri;
  $file->filemime = file_get_mimetype($file->filename);
  $file->filesize = $upload->filesize;

  // Support Transliteration.
  if (module_exists('transliteration') && variable_get('transliteration_file_uploads', TRUE)) {
    $orig_filename = $file->filename;
    $file->filename = transliteration_clean_filename($file->filename);
  }

  // Munge the filename.
  $validators = $element['#file_resup_upload_validators'];
  $extensions = '';
  if (isset($validators['file_validate_extensions'])) {
    if (isset($validators['file_validate_extensions'][0])) {
      $extensions = $validators['file_validate_extensions'][0];
    }
    else {
      unset($validators['file_validate_extensions']);
    }
  }
  else {
    $extensions = 'jpg jpeg gif png txt doc xls pdf ppt pps odt ods odp';
    $validators['file_validate_extensions'][] = $extensions;
  }
  if (!empty($extensions)) {
    $file->filename = file_munge_filename($file->filename, $extensions);
  }

  // Rename potentially executable files.
  if (!variable_get('allow_insecure_uploads', 0) && preg_match('/\\.(php|pl|py|cgi|asp|js)(\\.|$)/i', $file->filename) && substr($file->filename, -4) != '.txt') {
    $file->filemime = 'text/plain';
    $file->uri .= '.txt';
    $file->filename .= '.txt';
    if (!empty($extensions)) {
      $validators['file_validate_extensions'][0] .= ' txt';
      drupal_set_message(t('For security reasons, your upload has been renamed to %filename.', array(
        '%filename' => $file->filename,
      )));
    }
  }

  // Get the upload element name.
  $element_parents = $element['#parents'];
  if (end($element_parents) == 'resup') {
    unset($element_parents[key($element_parents)]);
  }
  $form_field_name = implode('_', $element_parents);

  // Run validators.
  $validators['file_validate_name_length'] = array();
  $errors = file_validate($file, $validators);
  if ($errors) {
    $message = t('The specified file %name could not be uploaded.', array(
      '%name' => $file->filename,
    ));
    if (count($errors) > 1) {
      $message .= theme('item_list', array(
        'items' => $errors,
      ));
    }
    else {
      $message .= ' ' . array_pop($errors);
    }
    form_set_error($form_field_name, $message);
    return FALSE;
  }

  // Prepare the destination directory.
  if (!file_prepare_directory($destination, FILE_CREATE_DIRECTORY)) {
    watchdog('file_resup', 'The upload directory %directory for the file field !name could not be created or is not accessible. A newly uploaded file could not be saved in this directory as a consequence, and the upload was canceled.', array(
      '%directory' => $destination,
      '!name' => $element['#field_name'],
    ));
    form_set_error($form_field_name, t('The file could not be uploaded.'));
    return FALSE;
  }

  // Complete the destination.
  if (substr($destination, -1) != '/') {
    $destination .= '/';
  }
  $destination = file_destination($destination . $file->filename, FILE_EXISTS_RENAME);

  // Move the uploaded file.
  $file->uri = $destination;
  if (!rename($upload_uri, $file->uri)) {
    form_set_error($form_field_name, t('File upload error. Could not move uploaded file.'));
    watchdog('file_resup', 'Upload error. Could not move uploaded file %file to destination %destination.', array(
      '%file' => $file->filename,
      '%destination' => $file->uri,
    ));
    return FALSE;
  }

  // Set the permissions on the new file.
  drupal_chmod($file->uri);

  // Transliteration support: restore the original filename if configured so.
  if (isset($orig_filename) && !variable_get('transliteration_file_uploads_display_name', TRUE)) {
    $file->filename = $orig_filename;
  }

  // Save the file object to the database.
  $file->file_resup_filesize = $upload->filesize;
  $file = file_save($file);
  if (!$file) {
    return FALSE;
  }

  // Update the upload record.
  $upload->fid = $file->fid;
  drupal_write_record('file_resup', $upload, 'upload_id');
  return $file;
}

/**
 * Implements hook_file_presave().
 */
function file_resup_file_presave($file) {

  // On 32bit platforms, filesize() may return unexpected results for files
  // larger than 2 GB and make drupal_write_record() crash.
  if (isset($file->file_resup_filesize)) {
    $file->filesize = $file->file_resup_filesize;
  }
  elseif (isset($file->original) && $file->original->filesize > PHP_INT_MAX) {

    // @todo We should not rely on $file->original because file might have been
    // replaced, but could not figure out a better solution so far...
    $file->filesize = $file->original->filesize;
  }
}

/**
 * Implements hook_file_insert().
 */
function file_resup_file_insert($file) {

  // drupal_write_record() cannot write a file size greater than 2 GB on 32bit
  // platforms.
  if ($file->filesize > PHP_INT_MAX) {
    db_query('UPDATE {file_managed} SET filesize = :filesize WHERE fid = :fid', array(
      ':filesize' => $file->filesize,
      ':fid' => $file->fid,
    ));
  }
}

/**
 * Implements hook_file_update().
 */
function file_resup_file_update($file) {
  file_resup_file_insert($file);
}

/**
 * Load an upload record.
 */
function file_resup_upload_load($upload_id) {
  $upload = db_query('SELECT * FROM {file_resup} WHERE upload_id = :upload_id', array(
    ':upload_id' => $upload_id,
  ))
    ->fetchObject();

  // If the upload has a fid, ensure it is still valid.
  if (!empty($upload->fid)) {
    $file = file_load($upload->fid);
    if (!$file || !in_array(file_uri_scheme($file->uri), variable_get('file_public_schema', array(
      'public',
    ))) && !file_download_access($file->uri)) {
      file_resup_upload_delete_record($upload);
      return;
    }
  }
  return $upload;
}

/**
 * Delete an upload record.
 */
function file_resup_upload_delete_record($upload) {
  db_query('DELETE FROM {file_resup} WHERE upload_id = :upload_id', array(
    ':upload_id' => $upload->upload_id,
  ));
}

/**
 * Delete an upload file.
 */
function file_resup_upload_delete_file($upload) {
  $uri = file_resup_upload_uri($upload);
  if (file_exists($uri)) {
    file_unmanaged_delete($uri);
  }
}

/**
 * Returns an upload uri.
 */
function file_resup_upload_uri($upload) {
  return $upload->scheme . '://' . FILE_RESUP_TEMPORARY . '/' . $upload->upload_id;
}

/**
 * Get a valid upload ID from a resup file ID.
 */
function file_resup_upload_id($resup_file_id) {
  global $user;
  if (preg_match('`^[1-9]\\d*-\\d+-[\\w%]+$`', $resup_file_id)) {
    $prefix = $user->uid ? $user->uid : str_replace('.', '_', $user->hostname);
    return substr($prefix . '-' . $resup_file_id, 0, 240);
  }
  return FALSE;
}

/**
 * Implements hook_cron().
 */
function file_resup_cron() {

  // Delete old uploads.
  $result = db_query('SELECT * FROM {file_resup} WHERE timestamp < :timestamp', array(
    ':timestamp' => REQUEST_TIME - DRUPAL_MAXIMUM_TEMP_FILE_AGE,
  ));
  foreach ($result as $upload) {
    file_resup_upload_delete_record($upload);
    file_resup_upload_delete_file($upload);
  }
}

/**
 * Returns the configured size of a file chunk.
 */
function file_resup_chunksize() {
  return variable_get('file_resup_chunksize', FILE_RESUP_DEFAULT_CHUNKSIZE);
}

Functions

Name	Description
file_resup_chunksize	Returns the configured size of a file chunk.
file_resup_cron	Implements hook_cron().
file_resup_file_insert	Implements hook_file_insert().
file_resup_file_presave	Implements hook_file_presave().
file_resup_file_update	Implements hook_file_update().
file_resup_menu	Implements hook_menu().
file_resup_permission	Implements hook_permission().
file_resup_plain_output	Returns data as plain text.
file_resup_save_upload	Save a completed upload.
file_resup_upload	Menu callback to upload a file chunk.
file_resup_upload_delete_file	Delete an upload file.
file_resup_upload_delete_record	Delete an upload record.
file_resup_upload_id	Get a valid upload ID from a resup file ID.
file_resup_upload_load	Load an upload record.
file_resup_upload_uri	Returns an upload uri.

Constants

Name	Description
FILE_RESUP_DEFAULT_CHUNKSIZE
FILE_RESUP_TEMPORARY