/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#ifndef __FORKSERVICE_CHILD_H_
#define __FORKSERVICE_CHILD_H_
#include "base/process_util.h"
#include "mozilla/GeckoArgs.h"
#include "nsIObserver.h"
#include "nsString.h"
#include "mozilla/ipc/MiniTransceiver.h"
#include "mozilla/ipc/LaunchError.h"
#include "mozilla/Result.h"
#include <sys/types.h>
#include <poll.h>
namespace mozilla {
namespace ipc {
class GeckoChildProcessHost;
/**
* This is the interface to the fork server.
*
* When the chrome process calls |ForkServiceChild| to create a new
* process, this class send a message to the fork server through a
* pipe and get the PID of the new process from the reply.
*/
class ForkServiceChild {
public:
ForkServiceChild(
int aFd, GeckoChildProcessHost* aProcess);
virtual ~ForkServiceChild();
/**
* Ask the fork server to create a new process with given parameters.
*
* \param aArgs arguments with file attachments used in the content process.
* \param aOptions other options which will be used to create the process.
* Not all launch options are supported.
* \param aPid returns the PID of the content
* process created. \return true if success.
*/
Result<Ok, LaunchError> SendForkNewSubprocess(
geckoargs::ChildProcessArgs&& aArgs, base::LaunchOptions&& aOptions,
pid_t* aPid);
/**
* Create a fork server process and the singleton of this class.
*
* This function uses |GeckoChildProcessHost| to launch the fork
* server, getting the fd of a pipe/socket to the fork server from
* it's |IPC::Channel|.
*/
static void StartForkServer();
static void StopForkServer();
/**
* Return the singleton.
*/
static ForkServiceChild* Get() {
auto child = sForkServiceChild.get();
return child == nullptr || child->mFailed ? nullptr : child;
}
/**
* Returns whether the fork server was ever active. Thread-safe.
*/
static bool WasUsed() {
return sForkServiceUsed; }
private:
// Called when a message is received.
void OnMessageReceived(UniquePtr<IPC::Message> message);
void OnError();
UniquePtr<MiniTransceiver> mTcver;
static UniquePtr<ForkServiceChild> sForkServiceChild;
static Atomic<
bool> sForkServiceUsed;
pid_t mRecvPid;
bool mFailed;
// The forkserver has crashed or disconnected.
GeckoChildProcessHost* mProcess;
};
/**
* Start a fork server at |xpcom-startup| from the chrome process.
*/
class ForkServerLauncher :
public nsIObserver {
public:
NS_DECL_ISUPPORTS
NS_DECL_NSIOBSERVER
ForkServerLauncher();
static already_AddRefed<ForkServerLauncher> Create();
private:
friend class ForkServiceChild;
virtual ~ForkServerLauncher();
static void RestartForkServer();
static bool mHaveStartedClient;
static StaticRefPtr<ForkServerLauncher> mSingleton;
};
}
// namespace ipc
}
// namespace mozilla
#endif /* __FORKSERVICE_CHILD_H_ */
