From 327b2bcd1b9ee17d6ac9b142743d228e42c365c8 Mon Sep 17 00:00:00 2001
From: Larry Garfield <larry@garfieldtech.com>
Date: Sat, 26 May 2012 12:33:25 -0500
Subject: [PATCH] Remove file_transfer and convert all uses of it to
 StreamedResponse.

---
 core/includes/file.inc          | 36 ++-------------------------------
 core/modules/image/image.module | 23 +++++++++++++++++----
 2 files changed, 21 insertions(+), 38 deletions(-)

diff --git a/core/includes/file.inc b/core/includes/file.inc
index 91e7ecaf136..1d2f54dc10c 100644
--- a/core/includes/file.inc
+++ b/core/includes/file.inc
@@ -1967,39 +1967,6 @@ function file_unmanaged_save_data($data, $destination = NULL, $replace = FILE_EX
   return file_unmanaged_move($temp_name, $destination, $replace);
 }
 
-/**
- * Transfers a file to the client using HTTP.
- *
- * Pipes a file through Drupal to the client.
- *
- * @param $uri
- *   String specifying the file URI to transfer.
- * @param $headers
- *   An array of HTTP headers to send along with file.
- */
-function file_transfer($uri, $headers) {
-  if (ob_get_level()) {
-    ob_end_clean();
-  }
-
-  foreach ($headers as $name => $value) {
-    drupal_add_http_header($name, $value);
-  }
-  drupal_send_headers();
-  $scheme = file_uri_scheme($uri);
-  // Transfer file in 1024 byte chunks to save memory usage.
-  if ($scheme && file_stream_wrapper_valid_scheme($scheme) && $fd = fopen($uri, 'rb')) {
-    while (!feof($fd)) {
-      print fread($fd, 1024);
-    }
-    fclose($fd);
-  }
-  else {
-    drupal_not_found();
-  }
-  drupal_exit();
-}
-
 /**
  * Page callback: Handles private file transfers.
  *
@@ -2529,7 +2496,8 @@ function file_directory_temp() {
  *   A file object.
  *
  * @return
- *   An associative array of headers, as expected by file_transfer().
+ *   An associative array of headers, as expected by
+ *   \Symfony\Component\HttpFoundation\StreamedResponse.
  */
 function file_get_content_headers($file) {
   $name = mime_header_encode($file->filename);
diff --git a/core/modules/image/image.module b/core/modules/image/image.module
index 3edf83c389a..2a445cfc9b7 100644
--- a/core/modules/image/image.module
+++ b/core/modules/image/image.module
@@ -5,6 +5,9 @@
  * Exposes global functionality for creating image styles.
  */
 
+use Symfony\Component\HttpFoundation\Response;
+use Symfony\Component\HttpFoundation\StreamedResponse;
+
 /**
  * Image style constant for user presets in the database.
  */
@@ -726,13 +729,25 @@ function image_style_deliver($style, $scheme) {
 
   if ($success) {
     $image = image_load($derivative_uri);
-    file_transfer($image->source, array('Content-Type' => $image->info['mime_type'], 'Content-Length' => $image->info['file_size']));
+    $uri = $image->source;
+    $headers = array(
+      'Content-Type' => $image->info['mime_type'],
+      'Content-Length' => $image->info['file_size'],
+    );
+    return new StreamedResponse(function() use ($uri) {
+      $scheme = file_uri_scheme($uri);
+      // Transfer file in 1024 byte chunks to save memory usage.
+      if ($scheme && file_stream_wrapper_valid_scheme($scheme) && $fd = fopen($uri, 'rb')) {
+        while (!feof($fd)) {
+          print fread($fd, 1024);
+        }
+        fclose($fd);
+      }
+    }, 200, $headers);
   }
   else {
     watchdog('image', 'Unable to generate the derived image located at %path.', array('%path' => $derivative_uri));
-    drupal_add_http_header('Status', '500 Internal Server Error');
-    print t('Error generating image.');
-    drupal_exit();
+    return new Response(t('Error generating image.'), 500);
   }
 }