blob: d3c7669a1b4ba171980a05128cb4d1b43144c08e [file] [log] [blame]
// Copyright 2014 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.
#include "base/macros.h"
#include "base/process/process_handle.h"
#include "mojo/embedder/platform_channel_pair.h"
#include "mojo/embedder/scoped_platform_handle.h"
#include "mojo/shell/child_process.h" // For |ChildProcess::Type|.
namespace mojo {
namespace shell {
class Context;
// (Base) class for a "child process host". Handles launching and connecting a
// platform-specific "pipe" to the child, and supports joining the child
// process. Intended for use as a base class, but may be used on its own in
// simple cases.
// This class is not thread-safe. It should be created/used/destroyed on a
// single thread.
// Note: Does not currently work on Windows before Vista.
class ChildProcessHost {
class Delegate {
virtual void WillStart() = 0;
virtual void DidStart(bool success) = 0;
ChildProcessHost(Context* context,
Delegate* delegate,
ChildProcess::Type type);
virtual ~ChildProcessHost();
// |Start()|s the child process; calls the delegate's |DidStart()| (on the
// thread on which |Start()| was called) when the child has been started (or
// failed to start). After calling |Start()|, this object must not be
// destroyed until |DidStart()| has been called.
// TODO(vtl): Consider using weak pointers and removing this requirement.
void Start();
// Waits for the child process to terminate, and returns its exit code.
// Note: If |Start()| has been called, this must not be called until the
// callback has been called.
int Join();
embedder::ScopedPlatformHandle* platform_channel() {
return &platform_channel_;
Context* context() const {
return context_;
bool DoLaunch();
void DidLaunch(bool success);
Context* const context_;
Delegate* const delegate_;
const ChildProcess::Type type_;
base::ProcessHandle child_process_handle_;
embedder::PlatformChannelPair platform_channel_pair_;
// Platform-specific "pipe" to the child process. Valid immediately after
// creation.
embedder::ScopedPlatformHandle platform_channel_;
} // namespace shell
} // namespace mojo