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Diffstat (limited to 'ipc/glue/ForkServiceChild.cpp')
| -rw-r--r-- | ipc/glue/ForkServiceChild.cpp | 190 |
1 files changed, 190 insertions, 0 deletions
diff --git a/ipc/glue/ForkServiceChild.cpp b/ipc/glue/ForkServiceChild.cpp new file mode 100644 index 0000000000..db130343cc --- /dev/null +++ b/ipc/glue/ForkServiceChild.cpp @@ -0,0 +1,190 @@ +/* -*- 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/. */ +#include "ForkServiceChild.h" +#include "ForkServer.h" +#include "mozilla/ipc/IPDLParamTraits.h" +#include "mozilla/Logging.h" +#include "mozilla/ipc/GeckoChildProcessHost.h" +#include "mozilla/ipc/ProtocolMessageUtils.h" +#include "mozilla/StaticPrefs_dom.h" +#include "mozilla/Services.h" +#include "ipc/IPCMessageUtilsSpecializations.h" +#include "nsIObserverService.h" + +#include <unistd.h> +#include <fcntl.h> + +namespace mozilla { +namespace ipc { + +extern LazyLogModule gForkServiceLog; + +mozilla::UniquePtr<ForkServiceChild> ForkServiceChild::sForkServiceChild; + +static bool ConfigurePipeFd(int aFd) { + int flags = fcntl(aFd, F_GETFD, 0); + return flags != -1 && fcntl(aFd, F_SETFD, flags | FD_CLOEXEC) != -1; +} + +void ForkServiceChild::StartForkServer() { + // Create the socket to use for communication, and mark both ends as + // FD_CLOEXEC. + int fds[2]; + if (socketpair(AF_UNIX, SOCK_STREAM, 0, fds) < 0) { + MOZ_LOG(gForkServiceLog, LogLevel::Error, + ("failed to create fork server socket")); + return; + } + UniqueFileHandle server(fds[0]); + UniqueFileHandle client(fds[1]); + + if (!ConfigurePipeFd(server.get()) || !ConfigurePipeFd(client.get())) { + MOZ_LOG(gForkServiceLog, LogLevel::Error, + ("failed to configure fork server socket")); + return; + } + + GeckoChildProcessHost* subprocess = + new GeckoChildProcessHost(GeckoProcessType_ForkServer, false); + subprocess->AddFdToRemap(client.get(), ForkServer::kClientPipeFd); + if (!subprocess->LaunchAndWaitForProcessHandle(std::vector<std::string>{})) { + MOZ_LOG(gForkServiceLog, LogLevel::Error, ("failed to launch fork server")); + return; + } + + sForkServiceChild = + mozilla::MakeUnique<ForkServiceChild>(server.release(), subprocess); +} + +void ForkServiceChild::StopForkServer() { sForkServiceChild = nullptr; } + +ForkServiceChild::ForkServiceChild(int aFd, GeckoChildProcessHost* aProcess) + : mFailed(false), mProcess(aProcess) { + mTcver = MakeUnique<MiniTransceiver>(aFd); +} + +ForkServiceChild::~ForkServiceChild() { + mProcess->Destroy(); + close(mTcver->GetFD()); +} + +Result<Ok, LaunchError> ForkServiceChild::SendForkNewSubprocess( + const nsTArray<nsCString>& aArgv, const nsTArray<EnvVar>& aEnvMap, + const nsTArray<FdMapping>& aFdsRemap, pid_t* aPid) { + mRecvPid = -1; + IPC::Message msg(MSG_ROUTING_CONTROL, Msg_ForkNewSubprocess__ID); + + IPC::MessageWriter writer(msg); + WriteIPDLParam(&writer, nullptr, aArgv); + WriteIPDLParam(&writer, nullptr, aEnvMap); + WriteIPDLParam(&writer, nullptr, aFdsRemap); + if (!mTcver->Send(msg)) { + MOZ_LOG(gForkServiceLog, LogLevel::Verbose, + ("the pipe to the fork server is closed or having errors")); + OnError(); + return Err(LaunchError("FSC::SFNS::Send")); + } + + UniquePtr<IPC::Message> reply; + if (!mTcver->Recv(reply)) { + MOZ_LOG(gForkServiceLog, LogLevel::Verbose, + ("the pipe to the fork server is closed or having errors")); + OnError(); + return Err(LaunchError("FSC::SFNS::Recv")); + } + OnMessageReceived(std::move(reply)); + + MOZ_ASSERT(mRecvPid != -1); + *aPid = mRecvPid; + return Ok(); +} + +void ForkServiceChild::OnMessageReceived(UniquePtr<IPC::Message> message) { + if (message->type() != Reply_ForkNewSubprocess__ID) { + MOZ_LOG(gForkServiceLog, LogLevel::Verbose, + ("unknown reply type %d", message->type())); + return; + } + IPC::MessageReader reader(*message); + + if (!ReadIPDLParam(&reader, nullptr, &mRecvPid)) { + MOZ_CRASH("Error deserializing 'pid_t'"); + } + reader.EndRead(); +} + +void ForkServiceChild::OnError() { + mFailed = true; + ForkServerLauncher::RestartForkServer(); +} + +NS_IMPL_ISUPPORTS(ForkServerLauncher, nsIObserver) + +bool ForkServerLauncher::mHaveStartedClient = false; +StaticRefPtr<ForkServerLauncher> ForkServerLauncher::mSingleton; + +ForkServerLauncher::ForkServerLauncher() {} + +ForkServerLauncher::~ForkServerLauncher() {} + +already_AddRefed<ForkServerLauncher> ForkServerLauncher::Create() { + if (mSingleton == nullptr) { + mSingleton = new ForkServerLauncher(); + } + RefPtr<ForkServerLauncher> launcher = mSingleton; + return launcher.forget(); +} + +NS_IMETHODIMP +ForkServerLauncher::Observe(nsISupports* aSubject, const char* aTopic, + const char16_t* aData) { + if (strcmp(aTopic, NS_XPCOM_STARTUP_CATEGORY) == 0) { + nsCOMPtr<nsIObserverService> obsSvc = + mozilla::services::GetObserverService(); + MOZ_ASSERT(obsSvc != nullptr); + // preferences are not available until final-ui-startup + obsSvc->AddObserver(this, "final-ui-startup", false); + } else if (!mHaveStartedClient && strcmp(aTopic, "final-ui-startup") == 0) { + if (StaticPrefs::dom_ipc_forkserver_enable_AtStartup()) { + mHaveStartedClient = true; + ForkServiceChild::StartForkServer(); + + nsCOMPtr<nsIObserverService> obsSvc = + mozilla::services::GetObserverService(); + MOZ_ASSERT(obsSvc != nullptr); + obsSvc->AddObserver(this, NS_XPCOM_SHUTDOWN_OBSERVER_ID, false); + } else { + mSingleton = nullptr; + } + } + + if (strcmp(aTopic, NS_XPCOM_SHUTDOWN_OBSERVER_ID) == 0) { + if (mHaveStartedClient) { + mHaveStartedClient = false; + ForkServiceChild::StopForkServer(); + } + + // To make leak checker happy! + mSingleton = nullptr; + } + return NS_OK; +} + +void ForkServerLauncher::RestartForkServer() { + // Restart fork server + NS_SUCCEEDED(NS_DispatchToMainThreadQueue( + NS_NewRunnableFunction("OnForkServerError", + [] { + if (mSingleton) { + ForkServiceChild::StopForkServer(); + ForkServiceChild::StartForkServer(); + } + }), + EventQueuePriority::Idle)); +} + +} // namespace ipc +} // namespace mozilla |