Merge "snapuserd: Refactor daemon/server." (8425f6e6) · Commits · e / os / android_system_core

fs_mgr/libsnapshot/include/libsnapshot/snapuserd_client.h

+3 −0

Original line number	Diff line number	Diff line
		@@ -26,6 +26,9 @@ namespace snapshot {
		static constexpr uint32_t PACKET_SIZE = 512;
		static constexpr uint32_t MAX_CONNECT_RETRY_COUNT = 10;

		static constexpr char kSnapuserdSocketFirstStage[] = "snapuserd_first_stage";
		static constexpr char kSnapuserdSocket[] = "snapuserd";

		class SnapuserdClient {
		private:
		int sockfd_ = 0;

fs_mgr/libsnapshot/include/libsnapshot/snapuserd_daemon.h

+4 −5

Original line number	Diff line number	Diff line
		@@ -25,22 +25,21 @@ class Daemon {
		// The Daemon class is a singleton to avoid
		// instantiating more than once
		public:
		Daemon() {}

		static Daemon& Instance() {
		static Daemon instance;
		return instance;
		}

		int StartServer(std::string socketname);
		bool IsRunning();
		bool StartServer(const std::string& socketname);
		void Run();
		void Interrupt();

		private:
		bool is_running_;
		std::unique_ptr<struct pollfd> poll_fd_;
		// Signal mask used with ppoll()
		sigset_t signal_mask_;

		Daemon();
		Daemon(Daemon const&) = delete;
		void operator=(Daemon const&) = delete;

fs_mgr/libsnapshot/include/libsnapshot/snapuserd_server.h

+16 −9

Original line number	Diff line number	Diff line
		@@ -14,6 +14,8 @@

		#pragma once

		#include <poll.h>

		#include <cstdio>
		#include <cstring>
		#include <functional>
		@@ -34,12 +36,11 @@ static constexpr uint32_t MAX_PACKET_SIZE = 512;
		enum class DaemonOperations {
		START,
		QUERY,
		TERMINATING,
		STOP,
		INVALID,
		};

		class Client {
		class DmUserHandler {
		private:
		std::unique_ptr<std::thread> threadHandler_;

		@@ -77,7 +78,15 @@ class SnapuserdServer : public Stoppable {
		private:
		android::base::unique_fd sockfd_;
		bool terminating_;
		std::vector<std::unique_ptr<Client>> clients_vec_;
		std::vector<std::unique_ptr<DmUserHandler>> dm_users_;
		std::vector<struct pollfd> watched_fds_;

		void AddWatchedFd(android::base::borrowed_fd fd);
		void AcceptClient();
		bool HandleClient(android::base::borrowed_fd fd, int revents);
		bool Recv(android::base::borrowed_fd fd, std::string* data);
		bool Sendmsg(android::base::borrowed_fd fd, const std::string& msg);
		bool Receivemsg(android::base::borrowed_fd fd, const std::string& msg);

		void ThreadStart(std::string cow_device, std::string backing_device,
		std::string control_device) override;
		@@ -92,13 +101,11 @@ class SnapuserdServer : public Stoppable {

		public:
		SnapuserdServer() { terminating_ = false; }
		~SnapuserdServer();

		int Start(std::string socketname);
		int AcceptClient();
		int Receivemsg(int fd);
		int Sendmsg(int fd, char* msg, size_t len);
		std::string Recvmsg(int fd, int* ret);
		android::base::borrowed_fd GetSocketFd() { return sockfd_; }
		bool Start(const std::string& socketname);
		bool Run();
		void Interrupt();
		};

		} // namespace snapshot

fs_mgr/libsnapshot/snapuserd.cpp

+9 −4

Original line number	Diff line number	Diff line
		@@ -17,6 +17,7 @@
		#include <csignal>

		#include <libsnapshot/snapuserd.h>
		#include <libsnapshot/snapuserd_client.h>
		#include <libsnapshot/snapuserd_daemon.h>
		#include <libsnapshot/snapuserd_server.h>

		@@ -482,13 +483,13 @@ int Snapuserd::WriteDmUserPayload(size_t size) {
		bool Snapuserd::Init() {
		backing_store_fd_.reset(open(backing_store_device_.c_str(), O_RDONLY));
		if (backing_store_fd_ < 0) {
		LOG(ERROR) << "Open Failed: " << backing_store_device_;
		PLOG(ERROR) << "Open Failed: " << backing_store_device_;
		return false;
		}

		cow_fd_.reset(open(cow_device_.c_str(), O_RDWR));
		if (cow_fd_ < 0) {
		LOG(ERROR) << "Open Failed: " << cow_device_;
		PLOG(ERROR) << "Open Failed: " << cow_device_;
		return false;
		}

		@@ -498,7 +499,7 @@ bool Snapuserd::Init() {

		ctrl_fd_.reset(open(control_path.c_str(), O_RDWR));
		if (ctrl_fd_ < 0) {
		LOG(ERROR) << "Unable to open " << control_path;
		PLOG(ERROR) << "Unable to open " << control_path;
		return false;
		}

		@@ -629,7 +630,11 @@ int main([[maybe_unused]] int argc, char** argv) {

		android::snapshot::Daemon& daemon = android::snapshot::Daemon::Instance();

		daemon.StartServer(argv[1]);
		std::string socket = android::snapshot::kSnapuserdSocket;
		if (argc >= 2) {
		socket = argv[1];
		}
		daemon.StartServer(socket);
		daemon.Run();

		return 0;

fs_mgr/libsnapshot/snapuserd_daemon.cpp

+9 −38

Original line number	Diff line number	Diff line
		@@ -20,16 +20,12 @@
		namespace android {
		namespace snapshot {

		int Daemon::StartServer(std::string socketname) {
		int ret;

		ret = server_.Start(socketname);
		if (ret < 0) {
		bool Daemon::StartServer(const std::string& socketname) {
		if (!server_.Start(socketname)) {
		LOG(ERROR) << "Snapuserd daemon failed to start...";
		exit(EXIT_FAILURE);
		}

		return ret;
		return true;
		}

		void Daemon::MaskAllSignalsExceptIntAndTerm() {
		@@ -51,51 +47,26 @@ void Daemon::MaskAllSignals() {
		}
		}

		Daemon::Daemon() {
		is_running_ = true;
		}

		bool Daemon::IsRunning() {
		return is_running_;
		}

		void Daemon::Run() {
		poll_fd_ = std::make_unique<struct pollfd>();
		poll_fd_->fd = server_.GetSocketFd().get();
		poll_fd_->events = POLLIN;

		sigfillset(&signal_mask_);
		sigdelset(&signal_mask_, SIGINT);
		sigdelset(&signal_mask_, SIGTERM);

		// Masking signals here ensure that after this point, we won't handle INT/TERM
		// until after we call into ppoll()
		MaskAllSignals();
		signal(SIGINT, Daemon::SignalHandler);
		signal(SIGTERM, Daemon::SignalHandler);
		signal(SIGPIPE, Daemon::SignalHandler);

		LOG(DEBUG) << "Snapuserd-server: ready to accept connections";

		while (IsRunning()) {
		int ret = ppoll(poll_fd_.get(), 1, nullptr, &signal_mask_);
		MaskAllSignalsExceptIntAndTerm();

		if (ret == -1) {
		PLOG(ERROR) << "Snapuserd:ppoll error";
		break;
		}

		if (poll_fd_->revents == POLLIN) {
		if (server_.AcceptClient() == static_cast<int>(DaemonOperations::STOP)) {
		Daemon::Instance().is_running_ = false;
		}
		server_.Run();
		}

		// Mask all signals to ensure that is_running_ can't become false between
		// checking it in the while condition and calling into ppoll()
		MaskAllSignals();
		}
		void Daemon::Interrupt() {
		server_.Interrupt();
		}

		void Daemon::SignalHandler(int signal) {
		@@ -103,7 +74,7 @@ void Daemon::SignalHandler(int signal) {
		switch (signal) {
		case SIGINT:
		case SIGTERM: {
		Daemon::Instance().is_running_ = false;
		Daemon::Instance().Interrupt();
		break;
		}
		case SIGPIPE: {