Merge "liblog: use a blocking socket for sending messages to logd" (d731184c) · Commits · e / os / android_system_core

liblog/logd_writer.cpp

+3 −55

Original line number	Diff line number	Diff line
		@@ -59,8 +59,7 @@ static void GetSocket() {
		return;
		}

		int new_socket =
		TEMP_FAILURE_RETRY(socket(PF_UNIX, SOCK_DGRAM \| SOCK_CLOEXEC \| SOCK_NONBLOCK, 0));
		int new_socket = TEMP_FAILURE_RETRY(socket(PF_UNIX, SOCK_DGRAM \| SOCK_CLOEXEC, 0));
		if (new_socket <= 0) {
		return;
		}
		@@ -91,8 +90,6 @@ int LogdWrite(log_id_t logId, struct timespec* ts, struct iovec* vec, size_t nr)
		struct iovec newVec[nr + headerLength];
		android_log_header_t header;
		size_t i, payloadSize;
		static atomic_int dropped;
		static atomic_int droppedSecurity;

		GetSocket();

		@@ -110,6 +107,7 @@ int LogdWrite(log_id_t logId, struct timespec* ts, struct iovec* vec, size_t nr)
		return 0;
		}

		header.id = logId;
		header.tid = gettid();
		header.realtime.tv_sec = ts->tv_sec;
		header.realtime.tv_nsec = ts->tv_nsec;
		@@ -117,44 +115,6 @@ int LogdWrite(log_id_t logId, struct timespec* ts, struct iovec* vec, size_t nr)
		newVec[0].iov_base = (unsigned char*)&header;
		newVec[0].iov_len = sizeof(header);

		int32_t snapshot = atomic_exchange_explicit(&droppedSecurity, 0, memory_order_relaxed);
		if (snapshot) {
		android_log_event_int_t buffer;

		header.id = LOG_ID_SECURITY;
		buffer.header.tag = LIBLOG_LOG_TAG;
		buffer.payload.type = EVENT_TYPE_INT;
		buffer.payload.data = snapshot;

		newVec[headerLength].iov_base = &buffer;
		newVec[headerLength].iov_len = sizeof(buffer);

		ret = TEMP_FAILURE_RETRY(writev(logd_socket, newVec, 2));
		if (ret != (ssize_t)(sizeof(header) + sizeof(buffer))) {
		atomic_fetch_add_explicit(&droppedSecurity, snapshot, memory_order_relaxed);
		}
		}
		snapshot = atomic_exchange_explicit(&dropped, 0, memory_order_relaxed);
		if (snapshot && __android_log_is_loggable_len(ANDROID_LOG_INFO, "liblog", strlen("liblog"),
		ANDROID_LOG_VERBOSE)) {
		android_log_event_int_t buffer;

		header.id = LOG_ID_EVENTS;
		buffer.header.tag = LIBLOG_LOG_TAG;
		buffer.payload.type = EVENT_TYPE_INT;
		buffer.payload.data = snapshot;

		newVec[headerLength].iov_base = &buffer;
		newVec[headerLength].iov_len = sizeof(buffer);

		ret = TEMP_FAILURE_RETRY(writev(logd_socket, newVec, 2));
		if (ret != (ssize_t)(sizeof(header) + sizeof(buffer))) {
		atomic_fetch_add_explicit(&dropped, snapshot, memory_order_relaxed);
		}
		}

		header.id = logId;

		for (payloadSize = 0, i = headerLength; i < nr + headerLength; i++) {
		newVec[i].iov_base = vec[i - headerLength].iov_base;
		payloadSize += newVec[i].iov_len = vec[i - headerLength].iov_len;
		@@ -168,11 +128,8 @@ int LogdWrite(log_id_t logId, struct timespec* ts, struct iovec* vec, size_t nr)
		}
		}

		// The write below could be lost, but will never block.
		// EAGAIN occurs if logd is overloaded, other errors indicate that something went wrong with
		// the connection, so we reset it and try again.
		ret = TEMP_FAILURE_RETRY(writev(logd_socket, newVec, i));
		if (ret < 0 && errno != EAGAIN) {
		if (ret < 0) {
		LogdConnect();

		ret = TEMP_FAILURE_RETRY(writev(logd_socket, newVec, i));
		@@ -182,14 +139,5 @@ int LogdWrite(log_id_t logId, struct timespec* ts, struct iovec* vec, size_t nr)
		ret = -errno;
		}

		if (ret > (ssize_t)sizeof(header)) {
		ret -= sizeof(header);
		} else if (ret < 0) {
		atomic_fetch_add_explicit(&dropped, 1, memory_order_relaxed);
		if (logId == LOG_ID_SECURITY) {
		atomic_fetch_add_explicit(&droppedSecurity, 1, memory_order_relaxed);
		}
		}

		return ret;
		}