platform_bootable_recovery/rotate_logs.cpp
Tianjie Xu e113e4d67f Cleanup the duplicates of logs rotation functions
Bug: 32067516
Test: Logs rotated successfully on angler, recovery-refresh/persist tests
passed on an a/b device.

Change-Id: Ie80adf0fa958ad3d7869d2d17f49489666b86c29
2016-11-03 18:16:33 -07:00

115 lines
3.7 KiB
C++

/*
* Copyright (C) 2016 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 "rotate_logs.h"
#include <stdio.h>
#include <string.h>
#include <sys/types.h>
#include <string>
#include <android-base/file.h>
#include <android-base/logging.h>
#include <android-base/parseint.h>
#include <android-base/stringprintf.h>
#include <private/android_logger.h> /* private pmsg functions */
static const std::string LAST_KMSG_FILTER = "recovery/last_kmsg";
static const std::string LAST_LOG_FILTER = "recovery/last_log";
ssize_t logbasename(
log_id_t /* logId */,
char /* prio */,
const char *filename,
const char * /* buf */, size_t len,
void *arg) {
bool* doRotate = static_cast<bool*>(arg);
if (LAST_KMSG_FILTER.find(filename) != std::string::npos ||
LAST_LOG_FILTER.find(filename) != std::string::npos) {
*doRotate = true;
}
return len;
}
ssize_t logrotate(
log_id_t logId,
char prio,
const char *filename,
const char *buf, size_t len,
void *arg) {
bool* doRotate = static_cast<bool*>(arg);
if (!*doRotate) {
return __android_log_pmsg_file_write(logId, prio, filename, buf, len);
}
std::string name(filename);
size_t dot = name.find_last_of('.');
std::string sub = name.substr(0, dot);
if (LAST_KMSG_FILTER.find(sub) == std::string::npos &&
LAST_LOG_FILTER.find(sub) == std::string::npos) {
return __android_log_pmsg_file_write(logId, prio, filename, buf, len);
}
// filename rotation
if (dot == std::string::npos) {
name += ".1";
} else {
std::string number = name.substr(dot + 1);
if (!isdigit(number[0])) {
name += ".1";
} else {
size_t i;
if (!android::base::ParseUint(number, &i)) {
LOG(ERROR) << "failed to parse uint in " << number;
return -1;
}
name = sub + "." + std::to_string(i + 1);
}
}
return __android_log_pmsg_file_write(logId, prio, name.c_str(), buf, len);
}
// Rename last_log -> last_log.1 -> last_log.2 -> ... -> last_log.$max.
// Similarly rename last_kmsg -> last_kmsg.1 -> ... -> last_kmsg.$max.
// Overwrite any existing last_log.$max and last_kmsg.$max.
void rotate_logs(const char* last_log_file, const char* last_kmsg_file) {
// Logs should only be rotated once.
static bool rotated = false;
if (rotated) {
return;
}
rotated = true;
for (int i = KEEP_LOG_COUNT - 1; i >= 0; --i) {
std::string old_log = android::base::StringPrintf("%s", last_log_file);
if (i > 0) {
old_log += "." + std::to_string(i);
}
std::string new_log = android::base::StringPrintf("%s.%d", last_log_file, i+1);
// Ignore errors if old_log doesn't exist.
rename(old_log.c_str(), new_log.c_str());
std::string old_kmsg = android::base::StringPrintf("%s", last_kmsg_file);
if (i > 0) {
old_kmsg += "." + std::to_string(i);
}
std::string new_kmsg = android::base::StringPrintf("%s.%d", last_kmsg_file, i+1);
rename(old_kmsg.c_str(), new_kmsg.c_str());
}
}