No media-file validation mode for DeviceMediaAsyncUtil.

CreateSnapshotFile and GetFileStreamReader used to sniff the content
of the files and returned error if it does not look like media data.
This CL adds a mode to disable the check, and use the disabled mode
in MTP mounting in Chrome OS file manager.

BUG=367004

Review URL: https://codereview.chromium.org/251723004

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@266524 0039d316-1c4b-4281-b951-d872f2087c98

chrome/browser/chromeos/fileapi/mtp_file_system_backend_delegate.cc

@@ -13,7 +13,8 @@ namespace chromeos {
 MTPFileSystemBackendDelegate::MTPFileSystemBackendDelegate(
     const base::FilePath& storage_partition_path)
     : device_media_async_file_util_(
-          DeviceMediaAsyncFileUtil::Create(storage_partition_path)) {
+          DeviceMediaAsyncFileUtil::Create(storage_partition_path,
+                                           NO_MEDIA_FILE_VALIDATION)) {
 }
 
 MTPFileSystemBackendDelegate::~MTPFileSystemBackendDelegate() {
@@ -34,10 +35,6 @@ MTPFileSystemBackendDelegate::CreateFileStreamReader(
     fileapi::FileSystemContext* context) {
   DCHECK_EQ(fileapi::kFileSystemTypeDeviceMediaAsFileStorage, url.type());
 
-  // TODO(kinaba): Returned MediaFileStreamReader verifies file header and
-  // stops reading if the stream does not represent a media file. We might
-  // want to remove the verification here since we want to mount MTP devices
-  // as normal file storage in Chrome OS file manager.
   return device_media_async_file_util_->GetFileStreamReader(
       url, offset, expected_modification_time, context);
 }

chrome/browser/media_galleries/fileapi/device_media_async_file_util.cc

@@ -64,9 +64,10 @@ DeviceMediaAsyncFileUtil::~DeviceMediaAsyncFileUtil() {
 
 // static
 DeviceMediaAsyncFileUtil* DeviceMediaAsyncFileUtil::Create(
-    const base::FilePath& profile_path) {
+    const base::FilePath& profile_path,
+    MediaFileValidationType validation_type) {
   DCHECK(!profile_path.empty());
-  return new DeviceMediaAsyncFileUtil(profile_path);
+  return new DeviceMediaAsyncFileUtil(profile_path, validation_type);
 }
 
 bool DeviceMediaAsyncFileUtil::SupportsStreaming(
@@ -283,12 +284,15 @@ DeviceMediaAsyncFileUtil::GetFileStreamReader(
   DCHECK(delegate->IsStreaming());
   return scoped_ptr<webkit_blob::FileStreamReader>(
       new ReadaheadFileStreamReader(new MTPFileStreamReader(
-          context, url, offset, expected_modification_time)));
+          context, url, offset, expected_modification_time,
+          validation_type_ == APPLY_MEDIA_FILE_VALIDATION)));
 }
 
 DeviceMediaAsyncFileUtil::DeviceMediaAsyncFileUtil(
-    const base::FilePath& profile_path)
+    const base::FilePath& profile_path,
+    MediaFileValidationType validation_type)
     : profile_path_(profile_path),
+      validation_type_(validation_type),
       weak_ptr_factory_(this) {
 }
 
@@ -322,18 +326,25 @@ void DeviceMediaAsyncFileUtil::OnDidCreateSnapshotFile(
     base::SequencedTaskRunner* media_task_runner,
     const base::File::Info& file_info,
     const base::FilePath& platform_path) {
-  base::PostTaskAndReplyWithResult(
-      media_task_runner,
-      FROM_HERE,
-      base::Bind(&NativeMediaFileUtil::IsMediaFile, platform_path),
-      base::Bind(&DeviceMediaAsyncFileUtil::OnDidCheckMedia,
-                 weak_ptr_factory_.GetWeakPtr(),
-                 callback,
-                 file_info,
-                 ShareableFileReference::GetOrCreate(
-                     platform_path,
-                     ShareableFileReference::DELETE_ON_FINAL_RELEASE,
-                     media_task_runner)));
+  scoped_refptr<webkit_blob::ShareableFileReference> file =
+      ShareableFileReference::GetOrCreate(
+                             platform_path,
+                             ShareableFileReference::DELETE_ON_FINAL_RELEASE,
+                             media_task_runner);
+
+  if (validation_type_ == APPLY_MEDIA_FILE_VALIDATION) {
+    base::PostTaskAndReplyWithResult(
+        media_task_runner,
+        FROM_HERE,
+        base::Bind(&NativeMediaFileUtil::IsMediaFile, platform_path),
+        base::Bind(&DeviceMediaAsyncFileUtil::OnDidCheckMedia,
+                   weak_ptr_factory_.GetWeakPtr(),
+                   callback,
+                   file_info,
+                   file));
+  } else {
+    OnDidCheckMedia(callback, file_info, file, base::File::FILE_OK);
+  }
 }
 
 void DeviceMediaAsyncFileUtil::OnDidCheckMedia(

chrome/browser/media_galleries/fileapi/device_media_async_file_util.h

@@ -30,6 +30,11 @@ namespace webkit_blob {
 class FileStreamReader;
 }
 
+enum MediaFileValidationType {
+  NO_MEDIA_FILE_VALIDATION,
+  APPLY_MEDIA_FILE_VALIDATION,
+};
+
 class DeviceMediaAsyncFileUtil : public fileapi::AsyncFileUtil {
  public:
   virtual ~DeviceMediaAsyncFileUtil();
@@ -37,7 +42,9 @@ class DeviceMediaAsyncFileUtil : public fileapi::AsyncFileUtil {
   // Returns an instance of DeviceMediaAsyncFileUtil. Returns NULL if
   // asynchronous operation is not supported. Callers own the returned
   // object.
-  static DeviceMediaAsyncFileUtil* Create(const base::FilePath& profile_path);
+  static DeviceMediaAsyncFileUtil* Create(
+      const base::FilePath& profile_path,
+      MediaFileValidationType validation_type);
 
   bool SupportsStreaming(const fileapi::FileSystemURL& url);
 
@@ -124,7 +131,8 @@ class DeviceMediaAsyncFileUtil : public fileapi::AsyncFileUtil {
 
  private:
   // Use Create() to get an instance of DeviceMediaAsyncFileUtil.
-  explicit DeviceMediaAsyncFileUtil(const base::FilePath& profile_path);
+  DeviceMediaAsyncFileUtil(const base::FilePath& profile_path,
+                           MediaFileValidationType validation_type);
 
   // Called when GetFileInfo method call succeeds. |file_info| contains the
   // file details of the requested url. |callback| is invoked to complete the
@@ -201,6 +209,8 @@ class DeviceMediaAsyncFileUtil : public fileapi::AsyncFileUtil {
   // Profile path.
   const base::FilePath profile_path_;
 
+  const MediaFileValidationType validation_type_;
+
   // For callbacks that may run after destruction.
   base::WeakPtrFactory<DeviceMediaAsyncFileUtil> weak_ptr_factory_;
 

chrome/browser/media_galleries/fileapi/media_file_system_backend.cc

@@ -127,7 +127,8 @@ MediaFileSystemBackend::MediaFileSystemBackend(
       native_media_file_util_(
           new NativeMediaFileUtil(media_path_filter_.get())),
       device_media_async_file_util_(
-          DeviceMediaAsyncFileUtil::Create(profile_path_))
+          DeviceMediaAsyncFileUtil::Create(profile_path_,
+                                           APPLY_MEDIA_FILE_VALIDATION))
 #if defined(OS_WIN) || defined(OS_MACOSX)
       ,
       picasa_file_util_(new picasa::PicasaFileUtil(media_path_filter_.get())),

chrome/browser/media_galleries/fileapi/mtp_file_stream_reader.cc

@@ -67,12 +67,13 @@ MTPFileStreamReader::MTPFileStreamReader(
     fileapi::FileSystemContext* file_system_context,
     const fileapi::FileSystemURL& url,
     int64 initial_offset,
-    const base::Time& expected_modification_time)
+    const base::Time& expected_modification_time,
+    bool do_media_header_validation)
     : file_system_context_(file_system_context),
       url_(url),
       current_offset_(initial_offset),
       expected_modification_time_(expected_modification_time),
-      media_header_validated_(false),
+      media_header_validated_(!do_media_header_validation),
       weak_factory_(this) {
 }
 

chrome/browser/media_galleries/fileapi/mtp_file_stream_reader.h

@@ -27,7 +27,8 @@ class MTPFileStreamReader
   MTPFileStreamReader(fileapi::FileSystemContext* file_system_context,
                       const fileapi::FileSystemURL& url,
                       int64 initial_offset,
-                      const base::Time& expected_modification_time);
+                      const base::Time& expected_modification_time,
+                      bool do_media_header_validation);
 
   virtual ~MTPFileStreamReader();