public/fidl/fuchsia.sys/environment.fidl

// 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.

library fuchsia.sys;

// Maximum length for an environment label.
const uint32 kLabelMaxLength = 32;

struct EnvironmentOptions {
  // True if this environment should inherit services provided by the
  // parent environment.
  bool inherit_parent_services;
  // True if components in this environment can share a runner provided
  // by the parent environment. If false, a new runner will be started
  // in this environment for components.
  bool allow_parent_runners;
  // True if this environment should be killed first in out of memory
  // situations by setting the ZX_PROP_JOB_KILL_ON_OOM property on this
  // environment's job.
  bool kill_on_oom;
};

// An interface for managing a set of applications.
//
// Applications run inside environments, which provide ambient services and
// support for their lifecycle.
[Discoverable] interface Environment {
  // Creates a new environment nested inside this environment.
  //
  // When applications are created inside the nested environment using the
  // environment's |Launcher|, the environment requests the
  // environment services from |host_directory| before passing those services to
  // the newly created application in its |StartupInfo|.
  //
  // The |controller| can be used to control the lifecycle of the created
  // environment. If an |EnvironmentController|'s interface is
  // request, the environment will be killed when the interface is closed.
  //
  // The |label| is an optional name to associate with the environment for
  // diagnostic purposes.  The label will be truncated if it is longer
  // than |kLabelMaxLength|.
  //
  // |additional_services|, which may be empty, contains a list of services
  // that the environment provides, which are hosted by
  // |additional_services.host_directory|. If |options.inherit_parent_services|
  // is false, |host_directory| must provide a |Loader| service if it wishes to
  // allow new components to be loaded in the new environment.
  //
  // |options| provides additional options, see |EnvironmentOptions| for
  // details.
  1: CreateNestedEnvironment(request<Environment> environment,
                             request<EnvironmentController>? controller,
                             string? label,
                             ServiceList? additional_services,
                             EnvironmentOptions options);

  // Gets the Launcher associated with this environment.
  //
  // Applications created using this application launcher will be given the
  // environment services provided by this environment's |host_directory|.
  2: GetLauncher(request<Launcher> launcher);

  // Gets a superset of services provided by this environment's
  // |host_directory|.
  3: GetServices(request<ServiceProvider> services);

  // Gets a superset of services provided by this environment's
  // |host_directory|.
  4: GetDirectory(handle<channel> directory_request);
};