// Copyright 2019 Google LLC
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

// A proto for serializing the sandbox2::MountTree class

syntax = "proto3";

package sandbox2;

// The MountTree maps path components to mount operations (bind/tmpfs). The path
// is encoded in the key of the entries map, with the root node representing /.
// To get the full path of a node, you will need to assemble the keys starting
// at the root node.
message MountTree {
  // FileNode represents a bind mount for a regular file using "outside" as the
  // source.
  message FileNode {
    string outside = 2;
    bool writable = 3;
  }

  // DirNode is like FileNode but for directories.
  message DirNode {
    string outside = 2;
    bool writable = 3;
  }

  // TmpfsNode mounts a tmpfs with given options.
  message TmpfsNode {
    string tmpfs_options = 1;
  }

  // RootNode is as special node for root of the MountTree
  message RootNode {
    bool writable = 3;
  }

  message Node {
    oneof node {
      FileNode file_node = 1;
      DirNode dir_node = 2;
      TmpfsNode tmpfs_node = 3;
      RootNode root_node = 4;
    }
  }

  // The entries are mappings from the next path component to the subtree.
  map<string, MountTree> entries = 1;

  // The node of the current path. If not set, we'll just create a directory at
  // this position.
  optional Node node = 2;

  // Helps to keep a stable and deterministic order of mounts. Protobuf makes no
  // guarantees about the order of map entries and may even randomize in certain
  // build configurations.
  int64 index = 3;
}