tombstoned: switch from goto to RAII. (9a61f685) · Commits · e / os / android_system_core

debuggerd/tombstoned/tombstoned.cpp

+55 −56

Original line number	Diff line number	Diff line
		@@ -48,6 +48,8 @@
		using android::base::GetIntProperty;
		using android::base::SendFileDescriptors;
		using android::base::StringPrintf;

		using android::base::borrowed_fd;
		using android::base::unique_fd;

		static InterceptManager* intercept_manager;
		@@ -98,6 +100,10 @@ class CrashQueue {
		return (crash->crash_type == kDebuggerdJavaBacktrace) ? for_anrs() : for_tombstones();
		}

		static CrashQueue* for_crash(const std::unique_ptr<Crash>& crash) {
		return for_crash(crash.get());
		}

		static CrashQueue* for_tombstones() {
		static CrashQueue queue("/data/tombstones", "tombstone_" /* file_name_prefix */,
		GetIntProperty("tombstoned.max_tombstone_count", 32),
		@@ -137,20 +143,21 @@ class CrashQueue {
		return file_name;
		}

		bool maybe_enqueue_crash(Crash* crash) {
		// Consumes crash if it returns true, otherwise leaves it untouched.
		bool maybe_enqueue_crash(std::unique_ptr<Crash>&& crash) {
		if (num_concurrent_dumps_ == max_concurrent_dumps_) {
		queued_requests_.push_back(crash);
		queued_requests_.emplace_back(std::move(crash));
		return true;
		}

		return false;
		}

		void maybe_dequeue_crashes(void (handler)(Crash crash)) {
		void maybe_dequeue_crashes(void (*handler)(std::unique_ptr<Crash> crash)) {
		while (!queued_requests_.empty() && num_concurrent_dumps_ < max_concurrent_dumps_) {
		Crash* next_crash = queued_requests_.front();
		std::unique_ptr<Crash> next_crash = std::move(queued_requests_.front());
		queued_requests_.pop_front();
		handler(next_crash);
		handler(std::move(next_crash));
		}
		}

		@@ -196,7 +203,7 @@ class CrashQueue {
		const size_t max_concurrent_dumps_;
		size_t num_concurrent_dumps_;

		std::deque<Crash*> queued_requests_;
		std::deque<std::unique_ptr<Crash>> queued_requests_;

		DISALLOW_COPY_AND_ASSIGN(CrashQueue);
		};
		@@ -209,7 +216,7 @@ static void crash_accept_cb(evconnlistener* listener, evutil_socket_t sockfd, so
		static void crash_request_cb(evutil_socket_t sockfd, short ev, void* arg);
		static void crash_completed_cb(evutil_socket_t sockfd, short ev, void* arg);

		static void perform_request(Crash* crash) {
		static void perform_request(std::unique_ptr<Crash> crash) {
		unique_fd output_fd;
		bool intercepted =
		intercept_manager->GetIntercept(crash->crash_pid, crash->crash_type, &output_fd);
		@@ -232,25 +239,24 @@ static void perform_request(Crash* crash) {

		if (rc == -1) {
		PLOG(WARNING) << "failed to send response to CrashRequest";
		goto fail;
		return;
		} else if (rc != sizeof(response)) {
		PLOG(WARNING) << "crash socket write returned short";
		goto fail;
		} else {
		return;
		}

		// TODO: Make this configurable by the interceptor?
		struct timeval timeout = {10, 0};

		event_base* base = event_get_base(crash->crash_event);

		event_assign(crash->crash_event, base, crash->crash_socket_fd, EV_TIMEOUT \| EV_READ,
		crash_completed_cb, crash);
		crash_completed_cb, crash.get());
		event_add(crash->crash_event, &timeout);
		}

		CrashQueue::for_crash(crash)->on_crash_started();
		return;

		fail:
		delete crash;
		// The crash is now owned by the event loop.
		crash.release();
		}

		static void crash_accept_cb(evconnlistener* listener, evutil_socket_t sockfd, sockaddr*, int,
		@@ -268,39 +274,37 @@ static void crash_accept_cb(evconnlistener* listener, evutil_socket_t sockfd, so
		}

		static void crash_request_cb(evutil_socket_t sockfd, short ev, void* arg) {
		ssize_t rc;
		Crash* crash = static_cast<Crash*>(arg);

		std::unique_ptr<Crash> crash(static_cast<Crash*>(arg));
		TombstonedCrashPacket request = {};

		if ((ev & EV_TIMEOUT) != 0) {
		LOG(WARNING) << "crash request timed out";
		goto fail;
		return;
		} else if ((ev & EV_READ) == 0) {
		LOG(WARNING) << "tombstoned received unexpected event from crash socket";
		goto fail;
		return;
		}

		rc = TEMP_FAILURE_RETRY(read(sockfd, &request, sizeof(request)));
		ssize_t rc = TEMP_FAILURE_RETRY(read(sockfd, &request, sizeof(request)));
		if (rc == -1) {
		PLOG(WARNING) << "failed to read from crash socket";
		goto fail;
		return;
		} else if (rc != sizeof(request)) {
		LOG(WARNING) << "crash socket received short read of length " << rc << " (expected "
		<< sizeof(request) << ")";
		goto fail;
		return;
		}

		if (request.packet_type != CrashPacketType::kDumpRequest) {
		LOG(WARNING) << "unexpected crash packet type, expected kDumpRequest, received "
		<< StringPrintf("%#2hhX", request.packet_type);
		goto fail;
		return;
		}

		crash->crash_type = request.packet.dump_request.dump_type;
		if (crash->crash_type < 0 \|\| crash->crash_type > kDebuggerdAnyIntercept) {
		LOG(WARNING) << "unexpected crash dump type: " << crash->crash_type;
		goto fail;
		return;
		}

		if (crash->crash_type != kDebuggerdJavaBacktrace) {
		@@ -314,51 +318,39 @@ static void crash_request_cb(evutil_socket_t sockfd, short ev, void* arg) {
		int ret = getsockopt(sockfd, SOL_SOCKET, SO_PEERCRED, &cr, &len);
		if (ret != 0) {
		PLOG(ERROR) << "Failed to getsockopt(..SO_PEERCRED)";
		goto fail;
		return;
		}

		crash->crash_pid = cr.pid;
		}

		LOG(INFO) << "received crash request for pid " << crash->crash_pid;
		pid_t crash_pid = crash->crash_pid;
		LOG(INFO) << "received crash request for pid " << crash_pid;

		if (CrashQueue::for_crash(crash)->maybe_enqueue_crash(crash)) {
		LOG(INFO) << "enqueueing crash request for pid " << crash->crash_pid;
		if (CrashQueue::for_crash(crash)->maybe_enqueue_crash(std::move(crash))) {
		LOG(INFO) << "enqueueing crash request for pid " << crash_pid;
		} else {
		perform_request(crash);
		perform_request(std::move(crash));
		}

		return;

		fail:
		delete crash;
		}

		static void crash_completed_cb(evutil_socket_t sockfd, short ev, void* arg) {
		ssize_t rc;
		Crash* crash = static_cast<Crash*>(arg);
		static void crash_completed(borrowed_fd sockfd, std::unique_ptr<Crash> crash) {
		TombstonedCrashPacket request = {};

		CrashQueue::for_crash(crash)->on_crash_completed();

		if ((ev & EV_READ) == 0) {
		goto fail;
		}

		rc = TEMP_FAILURE_RETRY(read(sockfd, &request, sizeof(request)));
		ssize_t rc = TEMP_FAILURE_RETRY(read(sockfd.get(), &request, sizeof(request)));
		if (rc == -1) {
		PLOG(WARNING) << "failed to read from crash socket";
		goto fail;
		return;
		} else if (rc != sizeof(request)) {
		LOG(WARNING) << "crash socket received short read of length " << rc << " (expected "
		<< sizeof(request) << ")";
		goto fail;
		return;
		}

		if (request.packet_type != CrashPacketType::kCompletedDump) {
		LOG(WARNING) << "unexpected crash packet type, expected kCompletedDump, received "
		<< uint32_t(request.packet_type);
		goto fail;
		return;
		}

		if (crash->crash_tombstone_fd != -1) {
		@@ -369,7 +361,7 @@ static void crash_completed_cb(evutil_socket_t sockfd, short ev, void* arg) {
		int rc = unlink(tombstone_path.c_str());
		if (rc != 0 && errno != ENOENT) {
		PLOG(ERROR) << "failed to unlink tombstone at " << tombstone_path;
		goto fail;
		return;
		}

		rc = linkat(AT_FDCWD, fd_path.c_str(), AT_FDCWD, tombstone_path.c_str(), AT_SYMLINK_FOLLOW);
		@@ -394,10 +386,17 @@ static void crash_completed_cb(evutil_socket_t sockfd, short ev, void* arg) {
		}
		}
		}
		}

		fail:
		static void crash_completed_cb(evutil_socket_t sockfd, short ev, void* arg) {
		std::unique_ptr<Crash> crash(static_cast<Crash*>(arg));
		CrashQueue* queue = CrashQueue::for_crash(crash);
		delete crash;

		CrashQueue::for_crash(crash)->on_crash_completed();

		if ((ev & EV_READ) == EV_READ) {
		crash_completed(sockfd, std::move(crash));
		}

		// If there's something queued up, let them proceed.
		queue->maybe_dequeue_crashes(perform_request);