Merge "liblog: use default tag for loggability checks if no tag is provided" (f74ad17a) · Commits · e / os / android_system_core

base/logging.cpp

+0 −1

Original line number	Diff line number	Diff line
		@@ -608,7 +608,6 @@ bool ShouldLog(LogSeverity severity, const char* tag) {
		// we need to fall back to using gMinimumLogSeverity, since __android_log_is_loggable() will not
		// take into consideration the value from SetMinimumLogSeverity().
		if (liblog_functions) {
		// TODO: It is safe to pass nullptr for tag, but it will be better to use the default log tag.
		int priority = LogSeverityToPriority(severity);
		return __android_log_is_loggable(priority, tag, ANDROID_LOG_INFO);
		} else {

liblog/logger_write.cpp

+4 −2

Original line number	Diff line number	Diff line
		@@ -14,6 +14,8 @@
		* limitations under the License.
		*/

		#include "logger_write.h"

		#include <errno.h>
		#include <inttypes.h>
		#include <libgen.h>
		@@ -136,11 +138,11 @@ static const char* getprogname() {
		// It's possible for logging to happen during static initialization before our globals are
		// initialized, so we place this std::string in a function such that it is initialized on the first
		// call.
		static std::string& GetDefaultTag() {
		std::string& GetDefaultTag() {
		static std::string default_tag = getprogname();
		return default_tag;
		}
		static RwLock default_tag_lock;
		RwLock default_tag_lock;

		void __android_log_set_default_tag(const char* tag) {
		auto lock = std::unique_lock{default_tag_lock};

liblog/logger_write.h

0 → 100644

+24 −0

Original line number	Diff line number	Diff line
		/*
		* Copyright (C) 2020 The Android Open Source Project
		*
		* Licensed under the Apache License, Version 2.0 (the "License");
		* you may not use this file except in compliance with the License.
		* You may obtain a copy of the License at
		*
		* http://www.apache.org/licenses/LICENSE-2.0
		*
		* Unless required by applicable law or agreed to in writing, software
		* distributed under the License is distributed on an "AS IS" BASIS,
		* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
		* See the License for the specific language governing permissions and
		* limitations under the License.
		*/

		#pragma once

		#include <string>

		#include "rwlock.h"

		std::string& GetDefaultTag(); // Must read lock default_tag_lock
		extern RwLock default_tag_lock;
		No newline at end of file

liblog/properties.cpp

+14 −4

Original line number	Diff line number	Diff line
		@@ -25,9 +25,12 @@
		#include <unistd.h>

		#include <algorithm>
		#include <shared_mutex>

		#include <private/android_logger.h>

		#include "logger_write.h"

		static pthread_mutex_t lock_loggable = PTHREAD_MUTEX_INITIALIZER;

		static int lock() {
		@@ -93,10 +96,17 @@ static int __android_log_level(const char* tag, size_t len) {
		/* sizeof() is used on this array below */
		static const char log_namespace[] = "persist.log.tag.";
		static const size_t base_offset = 8; /* skip "persist." */
		/* calculate the size of our key temporary buffer */
		const size_t taglen = tag ? len : 0;

		auto tag_lock = std::shared_lock{default_tag_lock, std::defer_lock};
		if (tag == nullptr \|\| len == 0) {
		tag_lock.lock();
		auto& tag_string = GetDefaultTag();
		tag = tag_string.c_str();
		len = tag_string.size();
		}

		/* sizeof(log_namespace) = strlen(log_namespace) + 1 */
		char key[sizeof(log_namespace) + taglen];
		char key[sizeof(log_namespace) + len];
		char* kp;
		size_t i;
		char c = 0;
		@@ -146,7 +156,7 @@ static int __android_log_level(const char* tag, size_t len) {
		}
		}

		if (taglen) {
		if (len) {
		int local_change_detected = change_detected;
		if (!not_locked) {
		if (!last_tag \|\| !last_tag[0] \|\| (last_tag[0] != tag[0]) \|\|

liblog/tests/liblog_default_tag.cpp

+44 −0

Original line number	Diff line number	Diff line
		@@ -97,3 +97,47 @@ TEST(liblog_default_tag, liblog_sets_default_tag) {
		LOG(WARNING) << "message";
		EXPECT_TRUE(message_seen);
		}

		TEST(liblog_default_tag, default_tag_plus_log_severity) {
		using namespace android::base;
		bool message_seen = false;
		std::string expected_tag = "liblog_test_tag";
		SetLogger([&](LogId, LogSeverity, const char* tag, const char, unsigned int, const char) {
		message_seen = true;
		EXPECT_EQ(expected_tag, tag);
		});
		__android_log_set_default_tag(expected_tag.c_str());

		auto log_tag_property = "log.tag." + expected_tag;
		SetProperty(log_tag_property, "V");

		__android_log_buf_write(LOG_ID_MAIN, ANDROID_LOG_VERBOSE, nullptr, "message");
		EXPECT_TRUE(message_seen);
		message_seen = false;

		LOG(VERBOSE) << "message";
		EXPECT_TRUE(message_seen);
		}

		TEST(liblog_default_tag, generated_default_tag_plus_log_severity) {
		using namespace android::base;
		bool message_seen = false;
		std::string expected_tag = getprogname();
		SetLogger([&](LogId, LogSeverity, const char* tag, const char, unsigned int, const char) {
		message_seen = true;
		EXPECT_EQ(expected_tag, tag);
		});

		// Even without any calls to SetDefaultTag(), the first message that attempts to log, will
		// generate a default tag from getprogname() and check log.tag.<default tag> for loggability. This
		// case checks that we can log a Verbose message when log.tag.<getprogname()> is set to 'V'.
		auto log_tag_property = "log.tag." + expected_tag;
		SetProperty(log_tag_property, "V");

		__android_log_buf_write(LOG_ID_MAIN, ANDROID_LOG_VERBOSE, nullptr, "message");
		EXPECT_TRUE(message_seen);
		message_seen = false;

		LOG(VERBOSE) << "message";
		EXPECT_TRUE(message_seen);
		}
		No newline at end of file