[REFACTOR] Split Android and CrOS logging.
Previously, they are all cramped in main.cc. Split them
into their respective files logging.cc, logging_android.cc
and provide a common header, logging.h, that main.cc can use.
Bug: 147696014
Bug: 148818798
Test: builds
Test: build logging.cc in Android
Change-Id: Iafdaee6be20e204f4faa1d1d8f81e43670f08d96
diff --git a/logging_android.cc b/logging_android.cc
new file mode 100644
index 0000000..ae1c8ed
--- /dev/null
+++ b/logging_android.cc
@@ -0,0 +1,109 @@
+//
+// 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 <inttypes.h>
+#include <stdio.h>
+#include <sys/stat.h>
+#include <unistd.h>
+
+#include <algorithm>
+#include <string>
+#include <vector>
+
+#include <base/files/dir_reader_posix.h>
+#include <base/logging.h>
+#include <base/strings/string_util.h>
+#include <base/strings/stringprintf.h>
+
+#include "update_engine/common/utils.h"
+
+using std::string;
+
+namespace chromeos_update_engine {
+namespace {
+
+constexpr char kSystemLogsRoot[] = "/data/misc/update_engine_log";
+constexpr size_t kLogCount = 5;
+
+// Keep the most recent |kLogCount| logs but remove the old ones in
+// "/data/misc/update_engine_log/".
+void DeleteOldLogs(const string& kLogsRoot) {
+ base::DirReaderPosix reader(kLogsRoot.c_str());
+ if (!reader.IsValid()) {
+ LOG(ERROR) << "Failed to read " << kLogsRoot;
+ return;
+ }
+
+ std::vector<string> old_logs;
+ while (reader.Next()) {
+ if (reader.name()[0] == '.')
+ continue;
+
+ // Log files are in format "update_engine.%Y%m%d-%H%M%S",
+ // e.g. update_engine.20090103-231425
+ uint64_t date;
+ uint64_t local_time;
+ if (sscanf(reader.name(),
+ "update_engine.%" PRIu64 "-%" PRIu64 "",
+ &date,
+ &local_time) == 2) {
+ old_logs.push_back(reader.name());
+ } else {
+ LOG(WARNING) << "Unrecognized log file " << reader.name();
+ }
+ }
+
+ std::sort(old_logs.begin(), old_logs.end(), std::greater<string>());
+ for (size_t i = kLogCount; i < old_logs.size(); i++) {
+ string log_path = kLogsRoot + "/" + old_logs[i];
+ if (unlink(log_path.c_str()) == -1) {
+ PLOG(WARNING) << "Failed to unlink " << log_path;
+ }
+ }
+}
+
+string SetupLogFile(const string& kLogsRoot) {
+ DeleteOldLogs(kLogsRoot);
+
+ return base::StringPrintf("%s/update_engine.%s",
+ kLogsRoot.c_str(),
+ utils::GetTimeAsString(::time(nullptr)).c_str());
+}
+
+} // namespace
+
+void SetupLogging(bool log_to_system, bool log_to_file) {
+ logging::LoggingSettings log_settings;
+ log_settings.lock_log = logging::DONT_LOCK_LOG_FILE;
+ log_settings.logging_dest = static_cast<logging::LoggingDestination>(
+ (log_to_system ? logging::LOG_TO_SYSTEM_DEBUG_LOG : 0) |
+ (log_to_file ? logging::LOG_TO_FILE : 0));
+ log_settings.log_file = nullptr;
+
+ string log_file;
+ if (log_to_file) {
+ log_file = SetupLogFile(kSystemLogsRoot);
+ log_settings.delete_old = logging::APPEND_TO_OLD_LOG_FILE;
+ log_settings.log_file = log_file.c_str();
+ }
+ logging::InitLogging(log_settings);
+
+ // The log file will have AID_LOG as group ID; this GID is inherited from the
+ // parent directory "/data/misc/update_engine_log" which sets the SGID bit.
+ chmod(log_file.c_str(), 0640);
+}
+
+} // namespace chromeos_update_engine
