Merge "liblog: add pstore write" (91581f19) · Commits · e / os / android_system_core

include/private/android_logger.h

+11 −1

Original line number	Diff line number	Diff line
		@@ -24,7 +24,17 @@
		#include <log/log.h>
		#include <log/log_read.h>

		/* Header Structure to logd */
		#define LOGGER_MAGIC 'l'

		/* Header Structure to pstore */
		typedef struct __attribute__((__packed__)) {
		uint8_t magic;
		uint16_t len;
		uint16_t uid;
		uint16_t pid;
		} android_pmsg_log_header_t;

		/* Header Structure to logd, and second header for pstore */
		typedef struct __attribute__((__packed__)) {
		typeof_log_id_t id;
		uint16_t tid;

liblog/logd_write.c

+48 −19

Original line number	Diff line number	Diff line
		@@ -62,6 +62,7 @@ static pthread_mutex_t log_init_lock = PTHREAD_MUTEX_INITIALIZER;
		static int log_fds[(int)LOG_ID_MAX] = { -1, -1, -1, -1, -1 };
		#else
		static int logd_fd = -1;
		static int pstore_fd = -1;
		#endif

		/*
		@@ -110,6 +111,12 @@ static int __write_to_log_initialize()
		logd_fd = -1;
		close(i);
		}
		if (pstore_fd >= 0) {
		i = pstore_fd;
		pstore_fd = -1;
		close(i);
		}
		pstore_fd = open("/dev/pmsg0", O_WRONLY);

		i = socket(PF_UNIX, SOCK_DGRAM \| SOCK_CLOEXEC, 0);
		if (i < 0) {
		@@ -156,32 +163,26 @@ static int __write_to_log_kernel(log_id_t log_id, struct iovec *vec, size_t nr)
		}
		} while (ret == -EINTR);
		#else
		static const unsigned header_length = 1;
		static const unsigned header_length = 2;
		struct iovec newVec[nr + header_length];
		struct android_log_header_t header;
		android_log_header_t header;
		android_pmsg_log_header_t pmsg_header;
		struct timespec ts;
		size_t i, payload_size;
		static uid_t last_uid = AID_ROOT; /* logd always starts up as AID_ROOT */
		static pid_t last_pid = (pid_t) -1;

		if (last_uid == AID_ROOT) { /* have we called to get the UID yet? */
		last_uid = getuid();
		}
		if (last_uid == AID_LOGD) { /* logd, after initialization and priv drop */
		/*
		* ignore log messages we send to ourself (logd).
		* Such log messages are often generated by libraries we depend on
		* which use standard Android logging.
		*/
		return 0;
		}

		if (logd_fd < 0) {
		return -EBADF;
		if (last_pid == (pid_t) -1) {
		last_pid = getpid();
		}

		/*
		* struct {
		* // what we provide
		* // whate we provire to pstore
		* android_pmsg_log_header_t pmsg_header;
		* // what we provide to socket
		* android_log_header_t header;
		* // caller provides
		* union {
		@@ -199,13 +200,20 @@ static int __write_to_log_kernel(log_id_t log_id, struct iovec *vec, size_t nr)

		clock_gettime(CLOCK_REALTIME, &ts);

		pmsg_header.magic = LOGGER_MAGIC;
		pmsg_header.len = sizeof(pmsg_header) + sizeof(header);
		pmsg_header.uid = last_uid;
		pmsg_header.pid = last_pid;

		header.id = log_id;
		header.tid = gettid();
		header.realtime.tv_sec = ts.tv_sec;
		header.realtime.tv_nsec = ts.tv_nsec;

		newVec[0].iov_base = (unsigned char *) &header;
		newVec[0].iov_len = sizeof(header);
		newVec[0].iov_base = (unsigned char *) &pmsg_header;
		newVec[0].iov_len = sizeof(pmsg_header);
		newVec[1].iov_base = (unsigned char *) &header;
		newVec[1].iov_len = sizeof(header);

		for (payload_size = 0, i = header_length; i < nr + header_length; i++) {
		newVec[i].iov_base = vec[i - header_length].iov_base;
		@@ -216,17 +224,38 @@ static int __write_to_log_kernel(log_id_t log_id, struct iovec *vec, size_t nr)
		if (newVec[i].iov_len) {
		++i;
		}
		payload_size = LOGGER_ENTRY_MAX_PAYLOAD;
		break;
		}
		}
		pmsg_header.len += payload_size;

		if (pstore_fd >= 0) {
		TEMP_FAILURE_RETRY(writev(pstore_fd, newVec, i));
		}

		if (last_uid == AID_LOGD) { /* logd, after initialization and priv drop */
		/*
		* ignore log messages we send to ourself (logd).
		* Such log messages are often generated by libraries we depend on
		* which use standard Android logging.
		*/
		return 0;
		}

		if (logd_fd < 0) {
		return -EBADF;
		}

		/*
		* The write below could be lost, but will never block.
		*
		* To logd, we drop the pmsg_header
		*
		* ENOTCONN occurs if logd dies.
		* EAGAIN occurs if logd is overloaded.
		*/
		ret = writev(logd_fd, newVec, i);
		ret = TEMP_FAILURE_RETRY(writev(logd_fd, newVec + 1, i - 1));
		if (ret < 0) {
		ret = -errno;
		if (ret == -ENOTCONN) {
		@@ -242,7 +271,7 @@ static int __write_to_log_kernel(log_id_t log_id, struct iovec *vec, size_t nr)
		return ret;
		}

		ret = writev(logd_fd, newVec, i);
		ret = TEMP_FAILURE_RETRY(writev(logd_fd, newVec + 1, i - 1));
		if (ret < 0) {
		ret = -errno;
		}