Merge branch '4.4' into 5.4

* 4.4:
  Update ExceptionInterface.php
  Flush with flush() after ob_end_flush()
  [HttpFoundation] Fix deleteFileAfterSend on client abortion
  fix sending request to paths containing multiple slashes

Author: derrabus

BinaryFileResponse.php

@@ -34,6 +34,7 @@ class BinaryFileResponse extends Response
     protected $offset = 0;
     protected $maxlen = -1;
     protected $deleteFileAfterSend = false;
+    protected $chunkSize = 8 * 1024;
 
     /**
      * @param \SplFileInfo|string $file               The file to stream
@@ -125,6 +126,22 @@ public function getFile()
         return $this->file;
     }
 
+    /**
+     * Sets the response stream chunk size.
+     *
+     * @return $this
+     */
+    public function setChunkSize(int $chunkSize): self
+    {
+        if ($chunkSize < 1 || $chunkSize > \PHP_INT_MAX) {
+            throw new \LogicException('The chunk size of a BinaryFileResponse cannot be less than 1 or greater than PHP_INT_MAX.');
+        }
+
+        $this->chunkSize = $chunkSize;
+
+        return $this;
+    }
+
     /**
      * Automatically sets the Last-Modified header according the file modification date.
      *
@@ -306,7 +323,23 @@ public function sendContent()
         $out = fopen('php://output', 'w');
         $file = fopen($this->file->getPathname(), 'r');
 
-        stream_copy_to_stream($file, $out, $this->maxlen, $this->offset);
+        ignore_user_abort(true);
+
+        if (0 !== $this->offset) {
+            fseek($file, $this->offset);
+        }
+
+        $length = $this->maxlen;
+        while ($length && !feof($file)) {
+            $read = ($length > $this->chunkSize) ? $this->chunkSize : $length;
+            $length -= $read;
+
+            stream_copy_to_stream($file, $out, $read);
+
+            if (connection_aborted()) {
+                break;
+            }
+        }
 
         fclose($out);
         fclose($file);

Response.php

@@ -1245,6 +1245,7 @@ public static function closeOutputBuffers(int $targetLevel, bool $flush): void
         while ($level-- > $targetLevel && ($s = $status[$level]) && (!isset($s['del']) ? !isset($s['flags']) || ($s['flags'] & $flags) === $flags : $s['del'])) {
             if ($flush) {
                 ob_end_flush();
+                flush();
             } else {
                 ob_end_clean();
             }