liblog: Add android_set_log_frontend am: 850d06e1c9 am: 9d68551f47 (94acd67b) · Commits · e / os / android_system_core

liblog/README

+12 −1

Original line number	Diff line number	Diff line
		@@ -108,6 +108,11 @@ SYNOPSIS

		int android_log_destroy(android_log_context *ctx)

		#include <log/log_frontend.h>

		int android_set_log_frontend(int frontend_flag)
		int android_get_log_frontend()

		Link with -llog

		DESCRIPTION
		@@ -162,6 +167,12 @@ DESCRIPTION
		when opening the sub-log. It is recommended to open the log
		ANDROID_LOG_RDONLY in these cases.

		android_set_log_frontend() selects frontend filters. Argument is either
		LOGGER_DEFAULT, LOGGER_LOGD or LOGGER_NULL. The latter drops all
		content on the floor. Both android_set_log_frontend() and
		android_get_log_frontend() return the current frontend mask, or a
		negative errno for any problems.

		ERRORS
		If messages fail, a negative error code will be returned to the caller.

		@@ -194,4 +205,4 @@ SEE ALSO



		17 Oct 2016 LIBLOG(3)
		08 Feb 2017 LIBLOG(3)

liblog/include/log/log_frontend.h

0 → 100644

+33 −0

Original line number	Diff line number	Diff line
		/*
		**
		** Copyright 2017, The Android Open Source Project
		**
		** This file is dual licensed. It may be redistributed and/or modified
		** under the terms of the Apache 2.0 License OR version 2 of the GNU
		** General Public License.
		*/

		#ifndef _LIBS_LOG_FRONTEND_H
		#define _LIBS_LOG_FRONTEND_H

		#ifdef __cplusplus
		extern "C" {
		#endif

		/*
		* Logging frontends, bit mask to select features. Function returns selection.
		*/
		#define LOGGER_DEFAULT 0x0
		#define LOGGER_LOGD 0x1
		#define LOGGER_KERNEL 0x2 /* Reserved/Deprecated */
		#define LOGGER_NULL 0x4 /* Does not release resources of other selections */

		/* Both return the selected frontend flag mask, or negative errno */
		int android_set_log_frontend(int frontend_flag);
		int android_get_log_frontend();

		#ifdef __cplusplus
		}
		#endif

		#endif /* _LIBS_LOG_FRONTEND_H */

liblog/logger_write.c

+65 −0

Original line number	Diff line number	Diff line
		@@ -25,6 +25,7 @@
		#endif

		#include <log/event_tag_map.h>
		#include <log/log_frontend.h>
		#include <private/android_filesystem_config.h>
		#include <private/android_logger.h>

		@@ -618,3 +619,67 @@ LIBLOG_ABI_PUBLIC int __android_log_security_bswrite(int32_t tag,

		return write_to_log(LOG_ID_SECURITY, vec, 4);
		}

		static int __write_to_log_null(log_id_t log_id, struct iovec* vec, size_t nr)
		{
		size_t len, i;

		if ((log_id < LOG_ID_MIN) \|\| (log_id >= LOG_ID_MAX)) {
		return -EINVAL;
		}

		for (len = i = 0; i < nr; ++i) {
		len += vec[i].iov_len;
		}
		if (!len) {
		return -EINVAL;
		}
		return len;
		}

		/* Following functions need access to our internal write_to_log status */

		LIBLOG_ABI_PUBLIC int android_set_log_frontend(int frontend_flag)
		{
		if (frontend_flag < 0) {
		return -EINVAL;
		}

		__android_log_lock();

		if (frontend_flag & LOGGER_NULL) {
		write_to_log = __write_to_log_null;

		__android_log_unlock();

		return LOGGER_NULL;
		}

		/* Anything else, act as if LOGGER_DEFAULT */

		/* generically we only expect these two values for write_to_log */
		if ((write_to_log != __write_to_log_init) &&
		(write_to_log != __write_to_log_daemon)) {
		write_to_log = __write_to_log_init;
		}

		__android_log_unlock();

		return LOGGER_DEFAULT;
		}

		LIBLOG_ABI_PUBLIC int android_get_log_frontend()
		{
		int ret = LOGGER_DEFAULT;

		__android_log_lock();
		if (write_to_log == __write_to_log_null) {
		ret = LOGGER_NULL;
		} else if ((write_to_log != __write_to_log_init) &&
		(write_to_log != __write_to_log_daemon)) {
		ret = -EINVAL;
		}
		__android_log_unlock();

		return ret;
		}

liblog/tests/liblog_test.cpp

+70 −0

Original line number	Diff line number	Diff line
		@@ -37,6 +37,7 @@
		#include <gtest/gtest.h>
		#include <log/logprint.h>
		#include <log/log_event_list.h>
		#include <log/log_frontend.h>
		#include <private/android_filesystem_config.h>
		#include <private/android_logger.h>

		@@ -225,6 +226,75 @@ TEST(liblog, __android_log_btwrite__android_logger_list_read) {
		#endif
		}

		// This test makes little sense standalone, and requires the tests ahead
		// and behind us, to make us whole. We could incorporate a prefix and
		// suffix test to make this standalone, but opted to not complicate this.
		TEST(liblog, android_set_log_frontend) {
		#ifdef __ANDROID__
		int logger = android_get_log_frontend();
		EXPECT_NE(LOGGER_NULL, logger);

		EXPECT_EQ(LOGGER_NULL, android_set_log_frontend(LOGGER_NULL));
		EXPECT_EQ(LOGGER_NULL, android_get_log_frontend());

		pid_t pid = getpid();

		struct logger_list *logger_list;
		ASSERT_TRUE(NULL != (logger_list = android_logger_list_open(
		LOG_ID_EVENTS, ANDROID_LOG_RDONLY \| ANDROID_LOG_NONBLOCK, 1000, pid)));

		log_time ts(CLOCK_MONOTONIC);
		ASSERT_LT(0, __android_log_btwrite(0, EVENT_TYPE_LONG, &ts, sizeof(ts)));

		usleep(1000000);

		int count = 0;

		for (;;) {
		log_msg log_msg;
		if (android_logger_list_read(logger_list, &log_msg) <= 0) {
		break;
		}

		ASSERT_EQ(log_msg.entry.pid, pid);

		if ((log_msg.entry.len != sizeof(android_log_event_long_t))
		\|\| (log_msg.id() != LOG_ID_EVENTS)) {
		continue;
		}

		android_log_event_long_t* eventData;
		eventData = reinterpret_cast<android_log_event_long_t*>(log_msg.msg());

		if (!eventData \|\| (eventData->payload.type != EVENT_TYPE_LONG)) {
		continue;
		}

		log_time tx(reinterpret_cast<char*>(&eventData->payload.data));
		if (ts == tx) {
		++count;
		}
		}

		android_logger_list_close(logger_list);

		EXPECT_EQ(logger, android_set_log_frontend(logger));
		EXPECT_EQ(logger, android_get_log_frontend());

		// False negative if liblog.__android_log_btwrite__android_logger_list_read
		// fails above, so we will likely succeed. But we will have so many
		// failures elsewhere that it is probably not worthwhile for us to
		// highlight yet another disappointment.
		EXPECT_EQ(0, count);
		// We also expect failures in the following tests if the set does not
		// react in an appropriate manner internally, yet passes, so we depend
		// on this test being in the middle of a series of tests performed in
		// the same process.
		#else
		GTEST_LOG_(INFO) << "This test does nothing.\n";
		#endif
		}

		#ifdef __ANDROID__
		static inline int32_t get4LE(const char* src)
		{