Filesystem interface for Mac PTP/MTP devices using ImageCaptureCore

BUG=151681


Review URL: https://chromiumcodereview.appspot.com/11416089

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@181532 0039d316-1c4b-4281-b951-d872f2087c98

2 files changed, 12 insertions, 5 deletions

diff --git a/webkit/fileapi/media/mtp_device_delegate.h b/webkit/fileapi/media/mtp_device_delegate.h
index a5e89ac..31569d2 100644
--- a/webkit/fileapi/media/mtp_device_delegate.h
+++ b/webkit/fileapi/media/mtp_device_delegate.h
@@ -31,14 +31,20 @@ class MTPDeviceDelegate {
   // Returns a pointer to a new instance of AbstractFileEnumerator to enumerate
   // the file entries of |root| path. The instance needs to be freed by the
   // caller, and its lifetime should not extend past when the current call
-  // returns to the main media task runner thread.
+  // returns to the main media task runner thread. Callers must ensure the
+  // lifetime of the enumerator is shorter than the MTPDeviceDelegate
+  // implementation itself. Calls to the enumerator are made in the context of
+  // a SeuqencedWorkerPool, and the enumerator may block while it is being
+  // called.
   virtual scoped_ptr<FileSystemFileUtil::AbstractFileEnumerator>
       CreateFileEnumerator(const base::FilePath& root,
                            bool recursive) = 0;
 
   // Updates the temporary snapshot file contents given by |local_path| with
   // media file contents given by |device_file_path| and also returns the
-  // metadata of the temporary file.
+  // metadata of the temporary file. All calls to this interface method are
+  // made in the context of a SequencedWorkerPool, and so only one call will be
+  // active at once. Implementations may block this pool.
   virtual base::PlatformFileError CreateSnapshotFile(
       const base::FilePath& device_file_path,
       const base::FilePath& local_path,
diff --git a/webkit/fileapi/media/mtp_device_file_system_config.h b/webkit/fileapi/media/mtp_device_file_system_config.h
index b7cd5d2..cf721e9 100644
--- a/webkit/fileapi/media/mtp_device_file_system_config.h
+++ b/webkit/fileapi/media/mtp_device_file_system_config.h
@@ -7,9 +7,10 @@
 
 #include "build/build_config.h"
 
-// Support MTP device file system for Windows, Linux and ChromeOS. Note that
-// OS_LINUX implies OS_CHROMEOS.
-#if defined(OS_WIN) || defined(OS_LINUX)
+// Support MTP device file system for Windows, Mac, Linux and ChromeOS.
+// Note that OS_LINUX implies OS_CHROMEOS.
+// TODO(gbillock): remove this header and make this default.
+#if defined(OS_WIN) || defined(OS_MACOSX) || defined(OS_LINUX)
 #define SUPPORT_MTP_DEVICE_FILESYSTEM
 #endif