logd/LogBufferTest.cpp - platform/system/core - Git at Google

 /*
  * 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.
  */

 #include "LogBufferTest.h"

 #include <unistd.h>

 #include <limits>
 #include <memory>
 #include <regex>
 #include <vector>

 #include <android-base/stringprintf.h>
 #include <android-base/strings.h>

 #include "LogBuffer.h"
 #include "LogReaderThread.h"
 #include "LogWriter.h"

 using android::base::Join;
 using android::base::Split;
 using android::base::StringPrintf;

 #ifndef __ANDROID__
 unsigned long __android_logger_get_buffer_size(log_id_t) {
     return 1024 * 1024;
 }

 bool __android_logger_valid_buffer_size(unsigned long) {
     return true;
 }
 #endif

 char* android::uidToName(uid_t) {
     return nullptr;
 }

 static std::vector<std::string> CompareLoggerEntries(const logger_entry& expected,
                                                      const logger_entry& result, bool ignore_len) {
     std::vector<std::string> errors;
     if (!ignore_len && expected.len != result.len) {
         errors.emplace_back(
                 StringPrintf("len: expected %" PRIu16 " vs %" PRIu16, expected.len, result.len));
     }
     if (expected.hdr_size != result.hdr_size) {
         errors.emplace_back(StringPrintf("hdr_size: %" PRIu16 " vs %" PRIu16, expected.hdr_size,
                                          result.hdr_size));
     }
     if (expected.pid != result.pid) {
         errors.emplace_back(
                 StringPrintf("pid: expected %" PRIi32 " vs %" PRIi32, expected.pid, result.pid));
     }
     if (expected.tid != result.tid) {
         errors.emplace_back(
                 StringPrintf("tid: expected %" PRIu32 " vs %" PRIu32, expected.tid, result.tid));
     }
     if (expected.sec != result.sec) {
         errors.emplace_back(
                 StringPrintf("sec: expected %" PRIu32 " vs %" PRIu32, expected.sec, result.sec));
     }
     if (expected.nsec != result.nsec) {
         errors.emplace_back(
                 StringPrintf("nsec: expected %" PRIu32 " vs %" PRIu32, expected.nsec, result.nsec));
     }
     if (expected.lid != result.lid) {
         errors.emplace_back(
                 StringPrintf("lid: expected %" PRIu32 " vs %" PRIu32, expected.lid, result.lid));
     }
     if (expected.uid != result.uid) {
         errors.emplace_back(
                 StringPrintf("uid: expected %" PRIu32 " vs %" PRIu32, expected.uid, result.uid));
     }
     return errors;
 }

 static std::string MakePrintable(std::string in) {
     if (in.size() > 80) {
         in = in.substr(0, 80) + "...";
     }
     std::string result;
     for (const char c : in) {
         if (isprint(c)) {
             result.push_back(c);
         } else {
             result.append(StringPrintf("\\%02x", static_cast<int>(c) & 0xFF));
         }
     }
     return result;
 }

 static std::string CompareMessages(const std::string& expected, const std::string& result) {
     if (expected == result) {
         return {};
     }
     size_t diff_index = 0;
     for (; diff_index < std::min(expected.size(), result.size()); ++diff_index) {
         if (expected[diff_index] != result[diff_index]) {
             break;
         }
     }

     if (diff_index < 80) {
         auto expected_short = MakePrintable(expected);
         auto result_short = MakePrintable(result);
         return StringPrintf("msg: expected '%s' vs '%s'", expected_short.c_str(),
                             result_short.c_str());
     }

     auto expected_short = MakePrintable(expected.substr(diff_index));
     auto result_short = MakePrintable(result.substr(diff_index));
     return StringPrintf("msg: index %zu: expected '%s' vs '%s'", diff_index, expected_short.c_str(),
                         result_short.c_str());
 }

 static std::string CompareRegexMessages(const std::string& expected, const std::string& result) {
     auto expected_pieces = Split(expected, std::string("\0", 1));
     auto result_pieces = Split(result, std::string("\0", 1));

     if (expected_pieces.size() != 3 || result_pieces.size() != 3) {
         return StringPrintf(
                 "msg: should have 3 null delimited strings found %d in expected, %d in result: "
                 "'%s' vs '%s'",
                 static_cast<int>(expected_pieces.size()), static_cast<int>(result_pieces.size()),
                 MakePrintable(expected).c_str(), MakePrintable(result).c_str());
     }
     if (expected_pieces[0] != result_pieces[0]) {
         return StringPrintf("msg: tag/priority mismatch expected '%s' vs '%s'",
                             MakePrintable(expected_pieces[0]).c_str(),
                             MakePrintable(result_pieces[0]).c_str());
     }
     std::regex expected_tag_regex(expected_pieces[1]);
     if (!std::regex_search(result_pieces[1], expected_tag_regex)) {
         return StringPrintf("msg: message regex mismatch expected '%s' vs '%s'",
                             MakePrintable(expected_pieces[1]).c_str(),
                             MakePrintable(result_pieces[1]).c_str());
     }
     if (expected_pieces[2] != result_pieces[2]) {
         return StringPrintf("msg: nothing expected after final null character '%s' vs '%s'",
                             MakePrintable(expected_pieces[2]).c_str(),
                             MakePrintable(result_pieces[2]).c_str());
     }
     return {};
 }

 void CompareLogMessages(const std::vector<LogMessage>& expected,
                         const std::vector<LogMessage>& result) {
     EXPECT_EQ(expected.size(), result.size());
     size_t end = std::min(expected.size(), result.size());
     size_t num_errors = 0;
     for (size_t i = 0; i < end; ++i) {
         auto errors =
                 CompareLoggerEntries(expected[i].entry, result[i].entry, expected[i].regex_compare);
         auto msg_error = expected[i].regex_compare
                                  ? CompareRegexMessages(expected[i].message, result[i].message)
                                  : CompareMessages(expected[i].message, result[i].message);
         if (!msg_error.empty()) {
             errors.emplace_back(msg_error);
         }
         if (!errors.empty()) {
             GTEST_LOG_(ERROR) << "Mismatch log message " << i << "\n" << Join(errors, "\n");
             ++num_errors;
         }
     }
     EXPECT_EQ(0U, num_errors);
 }

 void FixupMessages(std::vector<LogMessage>* messages) {
     for (auto& [entry, message, _] : *messages) {
         entry.hdr_size = sizeof(logger_entry);
         entry.len = message.size();
     }
 }

 TEST_P(LogBufferTest, smoke) {
     std::vector<LogMessage> log_messages = {
             {{
                      .pid = 1,
                      .tid = 1,
                      .sec = 1234,
                      .nsec = 323001,
                      .lid = LOG_ID_MAIN,
                      .uid = 0,
              },
              "smoke test"},
     };
     FixupMessages(&log_messages);
     LogMessages(log_messages);

     std::vector<LogMessage> read_log_messages;
     std::unique_ptr<LogWriter> test_writer(new TestWriter(&read_log_messages, nullptr));
     std::unique_ptr<FlushToState> flush_to_state = log_buffer_->CreateFlushToState(1, kLogMaskAll);
     EXPECT_TRUE(log_buffer_->FlushTo(test_writer.get(), *flush_to_state, nullptr));
     EXPECT_EQ(2ULL, flush_to_state->start());
     CompareLogMessages(log_messages, read_log_messages);
 }

 TEST_P(LogBufferTest, smoke_with_reader_thread) {
     std::vector<LogMessage> log_messages = {
             {{.pid = 1, .tid = 2, .sec = 10000, .nsec = 20001, .lid = LOG_ID_MAIN, .uid = 0},
              "first"},
             {{.pid = 10, .tid = 2, .sec = 10000, .nsec = 20002, .lid = LOG_ID_MAIN, .uid = 0},
              "second"},
             {{.pid = 100, .tid = 2, .sec = 10000, .nsec = 20003, .lid = LOG_ID_KERNEL, .uid = 0},
              "third"},
             {{.pid = 10, .tid = 2, .sec = 10000, .nsec = 20004, .lid = LOG_ID_MAIN, .uid = 0},
              "fourth"},
             {{.pid = 1, .tid = 2, .sec = 10000, .nsec = 20005, .lid = LOG_ID_RADIO, .uid = 0},
              "fifth"},
             {{.pid = 2, .tid = 2, .sec = 10000, .nsec = 20006, .lid = LOG_ID_RADIO, .uid = 0},
              "sixth"},
             {{.pid = 3, .tid = 2, .sec = 10000, .nsec = 20007, .lid = LOG_ID_RADIO, .uid = 0},
              "seventh"},
             {{.pid = 4, .tid = 2, .sec = 10000, .nsec = 20008, .lid = LOG_ID_MAIN, .uid = 0},
              "eighth"},
             {{.pid = 5, .tid = 2, .sec = 10000, .nsec = 20009, .lid = LOG_ID_CRASH, .uid = 0},
              "nineth"},
             {{.pid = 6, .tid = 2, .sec = 10000, .nsec = 20011, .lid = LOG_ID_MAIN, .uid = 0},
              "tenth"},
     };
     FixupMessages(&log_messages);
     LogMessages(log_messages);

     std::vector<LogMessage> read_log_messages;
     bool released = false;

     {
         auto lock = std::unique_lock{reader_list_.reader_threads_lock()};
         std::unique_ptr<LogWriter> test_writer(new TestWriter(&read_log_messages, &released));
         std::unique_ptr<LogReaderThread> log_reader(
                 new LogReaderThread(log_buffer_.get(), &reader_list_, std::move(test_writer), true,
                                     0, kLogMaskAll, 0, {}, 1, {}));
         reader_list_.reader_threads().emplace_back(std::move(log_reader));
     }

     while (!released) {
         usleep(5000);
     }
     {
         auto lock = std::unique_lock{reader_list_.reader_threads_lock()};
         EXPECT_EQ(0U, reader_list_.reader_threads().size());
     }
     CompareLogMessages(log_messages, read_log_messages);
 }

 // Generate random messages, set the 'sec' parameter explicit though, to be able to track the
 // expected order of messages.
 LogMessage GenerateRandomLogMessage(uint32_t sec) {
     auto rand_uint32 = [](int max) -> uint32_t { return rand() % max; };
     logger_entry entry = {
             .hdr_size = sizeof(logger_entry),
             .pid = rand() % 5000,
             .tid = rand_uint32(5000),
             .sec = sec,
             .nsec = rand_uint32(NS_PER_SEC),
             .lid = rand_uint32(LOG_ID_STATS),
             .uid = rand_uint32(100000),
     };

     // See comment in ChattyLogBuffer::Log() for why this is disallowed.
     if (entry.nsec % 1000 == 0) {
         ++entry.nsec;
     }

     if (entry.lid == LOG_ID_EVENTS) {
         entry.lid = LOG_ID_KERNEL;
     }

     std::string message;
     char priority = ANDROID_LOG_INFO + rand() % 2;
     message.push_back(priority);

     int tag_length = 2 + rand() % 10;
     for (int i = 0; i < tag_length; ++i) {
         message.push_back('a' + rand() % 26);
     }
     message.push_back('\0');

     int msg_length = 2 + rand() % 1000;
     for (int i = 0; i < msg_length; ++i) {
         message.push_back('a' + rand() % 26);
     }
     message.push_back('\0');

     entry.len = message.size();

     return {entry, message};
 }

 TEST_P(LogBufferTest, random_messages) {
     srand(1);
     std::vector<LogMessage> log_messages;
     for (size_t i = 0; i < 1000; ++i) {
         log_messages.emplace_back(GenerateRandomLogMessage(i));
     }
     LogMessages(log_messages);

     std::vector<LogMessage> read_log_messages;
     bool released = false;

     {
         auto lock = std::unique_lock{reader_list_.reader_threads_lock()};
         std::unique_ptr<LogWriter> test_writer(new TestWriter(&read_log_messages, &released));
         std::unique_ptr<LogReaderThread> log_reader(
                 new LogReaderThread(log_buffer_.get(), &reader_list_, std::move(test_writer), true,
                                     0, kLogMaskAll, 0, {}, 1, {}));
         reader_list_.reader_threads().emplace_back(std::move(log_reader));
     }

     while (!released) {
         usleep(5000);
     }
     {
         auto lock = std::unique_lock{reader_list_.reader_threads_lock()};
         EXPECT_EQ(0U, reader_list_.reader_threads().size());
     }
     CompareLogMessages(log_messages, read_log_messages);
 }

 TEST_P(LogBufferTest, read_last_sequence) {
     std::vector<LogMessage> log_messages = {
             {{.pid = 1, .tid = 2, .sec = 10000, .nsec = 20001, .lid = LOG_ID_MAIN, .uid = 0},
              "first"},
             {{.pid = 10, .tid = 2, .sec = 10000, .nsec = 20002, .lid = LOG_ID_MAIN, .uid = 0},
              "second"},
             {{.pid = 100, .tid = 2, .sec = 10000, .nsec = 20003, .lid = LOG_ID_MAIN, .uid = 0},
              "third"},
     };
     FixupMessages(&log_messages);
     LogMessages(log_messages);

     std::vector<LogMessage> read_log_messages;
     bool released = false;

     {
         auto lock = std::unique_lock{reader_list_.reader_threads_lock()};
         std::unique_ptr<LogWriter> test_writer(new TestWriter(&read_log_messages, &released));
         std::unique_ptr<LogReaderThread> log_reader(
                 new LogReaderThread(log_buffer_.get(), &reader_list_, std::move(test_writer), true,
                                     0, kLogMaskAll, 0, {}, 3, {}));
         reader_list_.reader_threads().emplace_back(std::move(log_reader));
     }

     while (!released) {
         usleep(5000);
     }
     {
         auto lock = std::unique_lock{reader_list_.reader_threads_lock()};
         EXPECT_EQ(0U, reader_list_.reader_threads().size());
     }
     std::vector<LogMessage> expected_log_messages = {log_messages.back()};
     CompareLogMessages(expected_log_messages, read_log_messages);
 }

 TEST_P(LogBufferTest, clear_logs) {
     // Log 3 initial logs.
     std::vector<LogMessage> log_messages = {
             {{.pid = 1, .tid = 2, .sec = 10000, .nsec = 20001, .lid = LOG_ID_MAIN, .uid = 0},
              "first"},
             {{.pid = 10, .tid = 2, .sec = 10000, .nsec = 20002, .lid = LOG_ID_MAIN, .uid = 0},
              "second"},
             {{.pid = 100, .tid = 2, .sec = 10000, .nsec = 20003, .lid = LOG_ID_MAIN, .uid = 0},
              "third"},
     };
     FixupMessages(&log_messages);
     LogMessages(log_messages);

     std::vector<LogMessage> read_log_messages;
     bool released = false;

     // Connect a blocking reader.
     {
         auto lock = std::unique_lock{reader_list_.reader_threads_lock()};
         std::unique_ptr<LogWriter> test_writer(new TestWriter(&read_log_messages, &released));
         std::unique_ptr<LogReaderThread> log_reader(
                 new LogReaderThread(log_buffer_.get(), &reader_list_, std::move(test_writer), false,
                                     0, kLogMaskAll, 0, {}, 1, {}));
         reader_list_.reader_threads().emplace_back(std::move(log_reader));
     }

     // Wait up to 250ms for the reader to read the first 3 logs.
     constexpr int kMaxRetryCount = 50;
     int count = 0;
     for (; count < kMaxRetryCount; ++count) {
         usleep(5000);
         auto lock = std::unique_lock{reader_list_.reader_threads_lock()};
         if (reader_list_.reader_threads().back()->start() == 4) {
             break;
         }
     }
     ASSERT_LT(count, kMaxRetryCount);

     // Clear the log buffer.
     log_buffer_->Clear(LOG_ID_MAIN, 0);

     // Log 3 more logs.
     std::vector<LogMessage> after_clear_messages = {
             {{.pid = 1, .tid = 2, .sec = 10000, .nsec = 20001, .lid = LOG_ID_MAIN, .uid = 0},
              "4th"},
             {{.pid = 10, .tid = 2, .sec = 10000, .nsec = 20002, .lid = LOG_ID_MAIN, .uid = 0},
              "5th"},
             {{.pid = 100, .tid = 2, .sec = 10000, .nsec = 20003, .lid = LOG_ID_MAIN, .uid = 0},
              "6th"},
     };
     FixupMessages(&after_clear_messages);
     LogMessages(after_clear_messages);

     // Wait up to 250ms for the reader to read the 3 additional logs.
     for (count = 0; count < kMaxRetryCount; ++count) {
         usleep(5000);
         auto lock = std::unique_lock{reader_list_.reader_threads_lock()};
         if (reader_list_.reader_threads().back()->start() == 7) {
             break;
         }
     }
     ASSERT_LT(count, kMaxRetryCount);

     // Release the reader, wait for it to get the signal then check that it has been deleted.
     {
         auto lock = std::unique_lock{reader_list_.reader_threads_lock()};
         reader_list_.reader_threads().back()->release_Locked();
     }
     while (!released) {
         usleep(5000);
     }
     {
         auto lock = std::unique_lock{reader_list_.reader_threads_lock()};
         EXPECT_EQ(0U, reader_list_.reader_threads().size());
     }

     // Check that we have read all 6 messages.
     std::vector<LogMessage> expected_log_messages = log_messages;
     expected_log_messages.insert(expected_log_messages.end(), after_clear_messages.begin(),
                                  after_clear_messages.end());
     CompareLogMessages(expected_log_messages, read_log_messages);

     // Finally, call FlushTo and ensure that only the 3 logs after the clear remain in the buffer.
     std::vector<LogMessage> read_log_messages_after_clear;
     std::unique_ptr<LogWriter> test_writer(new TestWriter(&read_log_messages_after_clear, nullptr));
     std::unique_ptr<FlushToState> flush_to_state = log_buffer_->CreateFlushToState(1, kLogMaskAll);
     EXPECT_TRUE(log_buffer_->FlushTo(test_writer.get(), *flush_to_state, nullptr));
     EXPECT_EQ(7ULL, flush_to_state->start());
     CompareLogMessages(after_clear_messages, read_log_messages_after_clear);
 }

 INSTANTIATE_TEST_CASE_P(LogBufferTests, LogBufferTest,
                         testing::Values("chatty", "serialized", "simple"));
	/*
	* 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.
	*/

	#include "LogBufferTest.h"

	#include <unistd.h>

	#include <limits>
	#include <memory>
	#include <regex>
	#include <vector>

	#include <android-base/stringprintf.h>
	#include <android-base/strings.h>

	#include "LogBuffer.h"
	#include "LogReaderThread.h"
	#include "LogWriter.h"

	using android::base::Join;
	using android::base::Split;
	using android::base::StringPrintf;

	#ifndef __ANDROID__
	unsigned long __android_logger_get_buffer_size(log_id_t) {
	return 1024 * 1024;
	}

	bool __android_logger_valid_buffer_size(unsigned long) {
	return true;
	}
	#endif

	char* android::uidToName(uid_t) {
	return nullptr;
	}

	static std::vector<std::string> CompareLoggerEntries(const logger_entry& expected,
	const logger_entry& result, bool ignore_len) {
	std::vector<std::string> errors;
	if (!ignore_len && expected.len != result.len) {
	errors.emplace_back(
	StringPrintf("len: expected %" PRIu16 " vs %" PRIu16, expected.len, result.len));
	}
	if (expected.hdr_size != result.hdr_size) {
	errors.emplace_back(StringPrintf("hdr_size: %" PRIu16 " vs %" PRIu16, expected.hdr_size,
	result.hdr_size));
	}
	if (expected.pid != result.pid) {
	errors.emplace_back(
	StringPrintf("pid: expected %" PRIi32 " vs %" PRIi32, expected.pid, result.pid));
	}
	if (expected.tid != result.tid) {
	errors.emplace_back(
	StringPrintf("tid: expected %" PRIu32 " vs %" PRIu32, expected.tid, result.tid));
	}
	if (expected.sec != result.sec) {
	errors.emplace_back(
	StringPrintf("sec: expected %" PRIu32 " vs %" PRIu32, expected.sec, result.sec));
	}
	if (expected.nsec != result.nsec) {
	errors.emplace_back(
	StringPrintf("nsec: expected %" PRIu32 " vs %" PRIu32, expected.nsec, result.nsec));
	}
	if (expected.lid != result.lid) {
	errors.emplace_back(
	StringPrintf("lid: expected %" PRIu32 " vs %" PRIu32, expected.lid, result.lid));
	}
	if (expected.uid != result.uid) {
	errors.emplace_back(
	StringPrintf("uid: expected %" PRIu32 " vs %" PRIu32, expected.uid, result.uid));
	}
	return errors;
	}

	static std::string MakePrintable(std::string in) {
	if (in.size() > 80) {
	in = in.substr(0, 80) + "...";
	}
	std::string result;
	for (const char c : in) {
	if (isprint(c)) {
	result.push_back(c);
	} else {
	result.append(StringPrintf("\\%02x", static_cast<int>(c) & 0xFF));
	}
	}
	return result;
	}

	static std::string CompareMessages(const std::string& expected, const std::string& result) {
	if (expected == result) {
	return {};
	}
	size_t diff_index = 0;
	for (; diff_index < std::min(expected.size(), result.size()); ++diff_index) {
	if (expected[diff_index] != result[diff_index]) {
	break;
	}
	}

	if (diff_index < 80) {
	auto expected_short = MakePrintable(expected);
	auto result_short = MakePrintable(result);
	return StringPrintf("msg: expected '%s' vs '%s'", expected_short.c_str(),
	result_short.c_str());
	}

	auto expected_short = MakePrintable(expected.substr(diff_index));
	auto result_short = MakePrintable(result.substr(diff_index));
	return StringPrintf("msg: index %zu: expected '%s' vs '%s'", diff_index, expected_short.c_str(),
	result_short.c_str());
	}

	static std::string CompareRegexMessages(const std::string& expected, const std::string& result) {
	auto expected_pieces = Split(expected, std::string("\0", 1));
	auto result_pieces = Split(result, std::string("\0", 1));

	if (expected_pieces.size() != 3 \|\| result_pieces.size() != 3) {
	return StringPrintf(
	"msg: should have 3 null delimited strings found %d in expected, %d in result: "
	"'%s' vs '%s'",
	static_cast<int>(expected_pieces.size()), static_cast<int>(result_pieces.size()),
	MakePrintable(expected).c_str(), MakePrintable(result).c_str());
	}
	if (expected_pieces[0] != result_pieces[0]) {
	return StringPrintf("msg: tag/priority mismatch expected '%s' vs '%s'",
	MakePrintable(expected_pieces[0]).c_str(),
	MakePrintable(result_pieces[0]).c_str());
	}
	std::regex expected_tag_regex(expected_pieces[1]);
	if (!std::regex_search(result_pieces[1], expected_tag_regex)) {
	return StringPrintf("msg: message regex mismatch expected '%s' vs '%s'",
	MakePrintable(expected_pieces[1]).c_str(),
	MakePrintable(result_pieces[1]).c_str());
	}
	if (expected_pieces[2] != result_pieces[2]) {
	return StringPrintf("msg: nothing expected after final null character '%s' vs '%s'",
	MakePrintable(expected_pieces[2]).c_str(),
	MakePrintable(result_pieces[2]).c_str());
	}
	return {};
	}

	void CompareLogMessages(const std::vector<LogMessage>& expected,
	const std::vector<LogMessage>& result) {
	EXPECT_EQ(expected.size(), result.size());
	size_t end = std::min(expected.size(), result.size());
	size_t num_errors = 0;
	for (size_t i = 0; i < end; ++i) {
	auto errors =
	CompareLoggerEntries(expected[i].entry, result[i].entry, expected[i].regex_compare);
	auto msg_error = expected[i].regex_compare
	? CompareRegexMessages(expected[i].message, result[i].message)
	: CompareMessages(expected[i].message, result[i].message);
	if (!msg_error.empty()) {
	errors.emplace_back(msg_error);
	}
	if (!errors.empty()) {
	GTEST_LOG_(ERROR) << "Mismatch log message " << i << "\n" << Join(errors, "\n");
	++num_errors;
	}
	}
	EXPECT_EQ(0U, num_errors);
	}

	void FixupMessages(std::vector<LogMessage>* messages) {
	for (auto& [entry, message, _] : *messages) {
	entry.hdr_size = sizeof(logger_entry);
	entry.len = message.size();
	}
	}

	TEST_P(LogBufferTest, smoke) {
	std::vector<LogMessage> log_messages = {
	{{
	.pid = 1,
	.tid = 1,
	.sec = 1234,
	.nsec = 323001,
	.lid = LOG_ID_MAIN,
	.uid = 0,
	},
	"smoke test"},
	};
	FixupMessages(&log_messages);
	LogMessages(log_messages);

	std::vector<LogMessage> read_log_messages;
	std::unique_ptr<LogWriter> test_writer(new TestWriter(&read_log_messages, nullptr));
	std::unique_ptr<FlushToState> flush_to_state = log_buffer_->CreateFlushToState(1, kLogMaskAll);
	EXPECT_TRUE(log_buffer_->FlushTo(test_writer.get(), *flush_to_state, nullptr));
	EXPECT_EQ(2ULL, flush_to_state->start());
	CompareLogMessages(log_messages, read_log_messages);
	}

	TEST_P(LogBufferTest, smoke_with_reader_thread) {
	std::vector<LogMessage> log_messages = {
	{{.pid = 1, .tid = 2, .sec = 10000, .nsec = 20001, .lid = LOG_ID_MAIN, .uid = 0},
	"first"},
	{{.pid = 10, .tid = 2, .sec = 10000, .nsec = 20002, .lid = LOG_ID_MAIN, .uid = 0},
	"second"},
	{{.pid = 100, .tid = 2, .sec = 10000, .nsec = 20003, .lid = LOG_ID_KERNEL, .uid = 0},
	"third"},
	{{.pid = 10, .tid = 2, .sec = 10000, .nsec = 20004, .lid = LOG_ID_MAIN, .uid = 0},
	"fourth"},
	{{.pid = 1, .tid = 2, .sec = 10000, .nsec = 20005, .lid = LOG_ID_RADIO, .uid = 0},
	"fifth"},
	{{.pid = 2, .tid = 2, .sec = 10000, .nsec = 20006, .lid = LOG_ID_RADIO, .uid = 0},
	"sixth"},
	{{.pid = 3, .tid = 2, .sec = 10000, .nsec = 20007, .lid = LOG_ID_RADIO, .uid = 0},
	"seventh"},
	{{.pid = 4, .tid = 2, .sec = 10000, .nsec = 20008, .lid = LOG_ID_MAIN, .uid = 0},
	"eighth"},
	{{.pid = 5, .tid = 2, .sec = 10000, .nsec = 20009, .lid = LOG_ID_CRASH, .uid = 0},
	"nineth"},
	{{.pid = 6, .tid = 2, .sec = 10000, .nsec = 20011, .lid = LOG_ID_MAIN, .uid = 0},
	"tenth"},
	};
	FixupMessages(&log_messages);
	LogMessages(log_messages);

	std::vector<LogMessage> read_log_messages;
	bool released = false;

	{
	auto lock = std::unique_lock{reader_list_.reader_threads_lock()};
	std::unique_ptr<LogWriter> test_writer(new TestWriter(&read_log_messages, &released));
	std::unique_ptr<LogReaderThread> log_reader(
	new LogReaderThread(log_buffer_.get(), &reader_list_, std::move(test_writer), true,
	0, kLogMaskAll, 0, {}, 1, {}));
	reader_list_.reader_threads().emplace_back(std::move(log_reader));
	}

	while (!released) {
	usleep(5000);
	}
	{
	auto lock = std::unique_lock{reader_list_.reader_threads_lock()};
	EXPECT_EQ(0U, reader_list_.reader_threads().size());
	}
	CompareLogMessages(log_messages, read_log_messages);
	}

	// Generate random messages, set the 'sec' parameter explicit though, to be able to track the
	// expected order of messages.
	LogMessage GenerateRandomLogMessage(uint32_t sec) {
	auto rand_uint32 = [](int max) -> uint32_t { return rand() % max; };
	logger_entry entry = {
	.hdr_size = sizeof(logger_entry),
	.pid = rand() % 5000,
	.tid = rand_uint32(5000),
	.sec = sec,
	.nsec = rand_uint32(NS_PER_SEC),
	.lid = rand_uint32(LOG_ID_STATS),
	.uid = rand_uint32(100000),
	};

	// See comment in ChattyLogBuffer::Log() for why this is disallowed.
	if (entry.nsec % 1000 == 0) {
	++entry.nsec;
	}

	if (entry.lid == LOG_ID_EVENTS) {
	entry.lid = LOG_ID_KERNEL;
	}

	std::string message;
	char priority = ANDROID_LOG_INFO + rand() % 2;
	message.push_back(priority);

	int tag_length = 2 + rand() % 10;
	for (int i = 0; i < tag_length; ++i) {
	message.push_back('a' + rand() % 26);
	}
	message.push_back('\0');

	int msg_length = 2 + rand() % 1000;
	for (int i = 0; i < msg_length; ++i) {
	message.push_back('a' + rand() % 26);
	}
	message.push_back('\0');

	entry.len = message.size();

	return {entry, message};
	}

	TEST_P(LogBufferTest, random_messages) {
	srand(1);
	std::vector<LogMessage> log_messages;
	for (size_t i = 0; i < 1000; ++i) {
	log_messages.emplace_back(GenerateRandomLogMessage(i));
	}
	LogMessages(log_messages);

	std::vector<LogMessage> read_log_messages;
	bool released = false;

	{
	auto lock = std::unique_lock{reader_list_.reader_threads_lock()};
	std::unique_ptr<LogWriter> test_writer(new TestWriter(&read_log_messages, &released));
	std::unique_ptr<LogReaderThread> log_reader(
	new LogReaderThread(log_buffer_.get(), &reader_list_, std::move(test_writer), true,
	0, kLogMaskAll, 0, {}, 1, {}));
	reader_list_.reader_threads().emplace_back(std::move(log_reader));
	}

	while (!released) {
	usleep(5000);
	}
	{
	auto lock = std::unique_lock{reader_list_.reader_threads_lock()};
	EXPECT_EQ(0U, reader_list_.reader_threads().size());
	}
	CompareLogMessages(log_messages, read_log_messages);
	}

	TEST_P(LogBufferTest, read_last_sequence) {
	std::vector<LogMessage> log_messages = {
	{{.pid = 1, .tid = 2, .sec = 10000, .nsec = 20001, .lid = LOG_ID_MAIN, .uid = 0},
	"first"},
	{{.pid = 10, .tid = 2, .sec = 10000, .nsec = 20002, .lid = LOG_ID_MAIN, .uid = 0},
	"second"},
	{{.pid = 100, .tid = 2, .sec = 10000, .nsec = 20003, .lid = LOG_ID_MAIN, .uid = 0},
	"third"},
	};
	FixupMessages(&log_messages);
	LogMessages(log_messages);

	std::vector<LogMessage> read_log_messages;
	bool released = false;

	{
	auto lock = std::unique_lock{reader_list_.reader_threads_lock()};
	std::unique_ptr<LogWriter> test_writer(new TestWriter(&read_log_messages, &released));
	std::unique_ptr<LogReaderThread> log_reader(
	new LogReaderThread(log_buffer_.get(), &reader_list_, std::move(test_writer), true,
	0, kLogMaskAll, 0, {}, 3, {}));
	reader_list_.reader_threads().emplace_back(std::move(log_reader));
	}

	while (!released) {
	usleep(5000);
	}
	{
	auto lock = std::unique_lock{reader_list_.reader_threads_lock()};
	EXPECT_EQ(0U, reader_list_.reader_threads().size());
	}
	std::vector<LogMessage> expected_log_messages = {log_messages.back()};
	CompareLogMessages(expected_log_messages, read_log_messages);
	}

	TEST_P(LogBufferTest, clear_logs) {
	// Log 3 initial logs.
	std::vector<LogMessage> log_messages = {
	{{.pid = 1, .tid = 2, .sec = 10000, .nsec = 20001, .lid = LOG_ID_MAIN, .uid = 0},
	"first"},
	{{.pid = 10, .tid = 2, .sec = 10000, .nsec = 20002, .lid = LOG_ID_MAIN, .uid = 0},
	"second"},
	{{.pid = 100, .tid = 2, .sec = 10000, .nsec = 20003, .lid = LOG_ID_MAIN, .uid = 0},
	"third"},
	};
	FixupMessages(&log_messages);
	LogMessages(log_messages);

	std::vector<LogMessage> read_log_messages;
	bool released = false;

	// Connect a blocking reader.
	{
	auto lock = std::unique_lock{reader_list_.reader_threads_lock()};
	std::unique_ptr<LogWriter> test_writer(new TestWriter(&read_log_messages, &released));
	std::unique_ptr<LogReaderThread> log_reader(
	new LogReaderThread(log_buffer_.get(), &reader_list_, std::move(test_writer), false,
	0, kLogMaskAll, 0, {}, 1, {}));
	reader_list_.reader_threads().emplace_back(std::move(log_reader));
	}

	// Wait up to 250ms for the reader to read the first 3 logs.
	constexpr int kMaxRetryCount = 50;
	int count = 0;
	for (; count < kMaxRetryCount; ++count) {
	usleep(5000);
	auto lock = std::unique_lock{reader_list_.reader_threads_lock()};
	if (reader_list_.reader_threads().back()->start() == 4) {
	break;
	}
	}
	ASSERT_LT(count, kMaxRetryCount);

	// Clear the log buffer.
	log_buffer_->Clear(LOG_ID_MAIN, 0);

	// Log 3 more logs.
	std::vector<LogMessage> after_clear_messages = {
	{{.pid = 1, .tid = 2, .sec = 10000, .nsec = 20001, .lid = LOG_ID_MAIN, .uid = 0},
	"4th"},
	{{.pid = 10, .tid = 2, .sec = 10000, .nsec = 20002, .lid = LOG_ID_MAIN, .uid = 0},
	"5th"},
	{{.pid = 100, .tid = 2, .sec = 10000, .nsec = 20003, .lid = LOG_ID_MAIN, .uid = 0},
	"6th"},
	};
	FixupMessages(&after_clear_messages);
	LogMessages(after_clear_messages);

	// Wait up to 250ms for the reader to read the 3 additional logs.
	for (count = 0; count < kMaxRetryCount; ++count) {
	usleep(5000);
	auto lock = std::unique_lock{reader_list_.reader_threads_lock()};
	if (reader_list_.reader_threads().back()->start() == 7) {
	break;
	}
	}
	ASSERT_LT(count, kMaxRetryCount);

	// Release the reader, wait for it to get the signal then check that it has been deleted.
	{
	auto lock = std::unique_lock{reader_list_.reader_threads_lock()};
	reader_list_.reader_threads().back()->release_Locked();
	}
	while (!released) {
	usleep(5000);
	}
	{
	auto lock = std::unique_lock{reader_list_.reader_threads_lock()};
	EXPECT_EQ(0U, reader_list_.reader_threads().size());
	}

	// Check that we have read all 6 messages.
	std::vector<LogMessage> expected_log_messages = log_messages;
	expected_log_messages.insert(expected_log_messages.end(), after_clear_messages.begin(),
	after_clear_messages.end());
	CompareLogMessages(expected_log_messages, read_log_messages);

	// Finally, call FlushTo and ensure that only the 3 logs after the clear remain in the buffer.
	std::vector<LogMessage> read_log_messages_after_clear;
	std::unique_ptr<LogWriter> test_writer(new TestWriter(&read_log_messages_after_clear, nullptr));
	std::unique_ptr<FlushToState> flush_to_state = log_buffer_->CreateFlushToState(1, kLogMaskAll);
	EXPECT_TRUE(log_buffer_->FlushTo(test_writer.get(), *flush_to_state, nullptr));
	EXPECT_EQ(7ULL, flush_to_state->start());
	CompareLogMessages(after_clear_messages, read_log_messages_after_clear);
	}

	INSTANTIATE_TEST_CASE_P(LogBufferTests, LogBufferTest,
	testing::Values("chatty", "serialized", "simple"));