volume_mounter.mojom

// Copyright 2017 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.

// Next MinVersion: 4

module arc.mojom;

[Extensible]
enum MountEvent {
  // Mounts a volume in Android.
  MOUNTING,
  // Unmounts a volume in Android.
  UNMOUNTING,
};

[Extensible]
enum DeviceType {
  // Neither USB device nor SD card is inserted.
  DEVICE_TYPE_UNKNOWN,
  // USB device is inserted.
  DEVICE_TYPE_USB,
  // SD card is inserted.
  DEVICE_TYPE_SD,
};

struct MountPointInfo {
  // The type of mount event to be triggered in Android.
  MountEvent mount_event;
  // The device source path of this mount point.
  string source_path;
  // The path to the mounted volume.
  string mount_path;
  // The fs_uuid of the disk. If empty, the event should be ignored.
  string fs_uuid;
  // The file system label.
  string label;
  // The device type that contains this mount point. If unknown, the event
  // should be ignored.
  DeviceType device_type;
  // Whether the mounted volume should be visible to Android apps.
  // This is a user-controlled setting, which is accessible in "External
  // storage preferences" screen in device settings.
  [MinVersion=2] bool visible;
};

// Next Method ID: 3
interface VolumeMounterHost {
  // Requests all recorded MountPointInfos to be sent through a series of
  // VolumeMounterInstance::OnMountEvent call.
  [MinVersion=0] RequestAllMountPoints@1();

  // Reports the number of mount failures for a volume. The value 0 indicates
  // that the volume is successfully mounted without any failures. The maximum
  // number (defined in Android's ArcVolumeMounterService) indicates that
  // mounting the volume is given up after failing in maximum number of retries.
  // A value n between them indicates that the volume is successfully mounted
  // after n failures (= n retries).
  // This method is called basically once for each volume, i.e., it's called
  // once for the MyFiles volume after every Android boot, and called once every
  // time a removable media device is inserted to Chrome OS. An exception is
  // when a volume is ejected before it's mounted, in which time it's not
  // called at all. Also, when Android's volume daemon (vold) is reset, all
  // volumes are remounted and this method is called again for each of them.
  [MinVersion=3] ReportMountFailureCount@2(uint16 count);
};

// Notifies Android about Mounting events.
// Next Method ID: 2
interface VolumeMounterInstance {
  // Establishes full-duplex communication with the host.
  [MinVersion=1] Init@0(pending_remote<VolumeMounterHost> host_remote) => ();

  // Triggers a mount event in Android.
  OnMountEvent@1(MountPointInfo mount_point_info);
};