Motown: New wrapper classes for ffmpeg format context and io context

services/media/framework/parts/file_reader.cc

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include <cstdio>
 
 #include "base/files/file_util.h"
 #include "services/media/framework/parts/file_reader.h"
 #include "url/gurl.h"
 
@@ skipping 16 matching lines @@
   }
 
   if (fseek(file_, 0, SEEK_END) == 0) {
     size_ = ftell(file_);
     if (fseek(file_, 0, SEEK_SET) < 0) {
       fclose(file_);
       file_ = nullptr;
       return Result::kUnsupportedOperation;
     }
   } else {
-    size_ = -1;
+    size_ = kFailed;
   }
 
   return Result::kOk;
 }
 
 size_t FileReader::Read(uint8_t* buffer, size_t bytes_to_read) {
-  return fread(buffer, 1, bytes_to_read, file_);
+  size_t bytes_read = fread(buffer, 1, bytes_to_read, file_);
+  if (bytes_read != bytes_to_read && ferror(file_) != 0) {
+    bytes_read = kFailed;
+  }
+  return bytes_read;
 }
 
 int64_t FileReader::GetPosition() const {
   return ftell(file_);
 }
 
 int64_t FileReader::SetPosition(int64_t position) {
   if (fseek(file_, position, SEEK_SET) < 0) {
     return -1;
   }
   return position;
 }
 
 size_t FileReader::GetSize() const {
   return size_;
 }
 
 bool FileReader::CanSeek() const {
   return true;
 }
 
 } // namespace media
 } // namespace mojo