platform_system_core/logd/LogBuffer.h
Tom Cherry 517808981e logd: don't check of the timestamp of audit messages is monotonic
This is the last isMonotonic() user and can go away.  This timestamp
is set in the kernel source in either the audit_get_stamp() or
__audit_syscall_entry() functions.  In both cases, the value used is
from ktime_get_coarse_real_ts64(), which is a realtime timestamp.

Test: audit messages show in the log correctly.
Change-Id: Ife6c09dd97fccdfc7a8f07ee63161079ae2eccc4
2020-05-06 13:37:33 -07:00

125 lines
4.2 KiB
C++

/*
* Copyright (C) 2012-2014 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 <sys/types.h>
#include <list>
#include <optional>
#include <string>
#include <android/log.h>
#include <private/android_filesystem_config.h>
#include <sysutils/SocketClient.h>
#include "LogBufferElement.h"
#include "LogReaderThread.h"
#include "LogStatistics.h"
#include "LogTags.h"
#include "LogWhiteBlackList.h"
typedef std::list<LogBufferElement*> LogBufferElementCollection;
class LogBuffer {
LogBufferElementCollection mLogElements;
pthread_rwlock_t mLogElementsLock;
LogStatistics stats;
// watermark of any worst/chatty uid processing
typedef std::unordered_map<uid_t, LogBufferElementCollection::iterator>
LogBufferIteratorMap;
LogBufferIteratorMap mLastWorst[LOG_ID_MAX];
// watermark of any worst/chatty pid of system processing
typedef std::unordered_map<pid_t, LogBufferElementCollection::iterator>
LogBufferPidIteratorMap;
LogBufferPidIteratorMap mLastWorstPidOfSystem[LOG_ID_MAX];
unsigned long mMaxSize[LOG_ID_MAX];
LogBufferElement* lastLoggedElements[LOG_ID_MAX];
LogBufferElement* droppedElements[LOG_ID_MAX];
void log(LogBufferElement* elem);
public:
LastLogTimes& mTimes;
LogBuffer(LastLogTimes* times, LogTags* tags, PruneList* prune);
~LogBuffer();
void init();
int log(log_id_t log_id, log_time realtime, uid_t uid, pid_t pid, pid_t tid, const char* msg,
uint16_t len);
// lastTid is an optional context to help detect if the last previous
// valid message was from the same source so we can differentiate chatty
// filter types (identical or expired)
uint64_t flushTo(SocketClient* writer, uint64_t start,
pid_t* lastTid, // &lastTid[LOG_ID_MAX] or nullptr
bool privileged, bool security,
const std::function<int(const LogBufferElement* element)>& filter);
bool clear(log_id_t id, uid_t uid = AID_ROOT);
unsigned long getSize(log_id_t id);
int setSize(log_id_t id, unsigned long size);
unsigned long getSizeUsed(log_id_t id);
std::string formatStatistics(uid_t uid, pid_t pid, unsigned int logMask);
void enableStatistics() {
stats.enableStatistics();
}
// helper must be protected directly or implicitly by wrlock()/unlock()
const char* pidToName(pid_t pid) {
return stats.pidToName(pid);
}
uid_t pidToUid(pid_t pid) { return stats.pidToUid(pid); }
const char* uidToName(uid_t uid) {
return stats.uidToName(uid);
}
void wrlock() {
pthread_rwlock_wrlock(&mLogElementsLock);
}
void rdlock() {
pthread_rwlock_rdlock(&mLogElementsLock);
}
void unlock() {
pthread_rwlock_unlock(&mLogElementsLock);
}
private:
static constexpr size_t minPrune = 4;
static constexpr size_t maxPrune = 256;
void maybePrune(log_id_t id);
void kickMe(LogReaderThread* me, log_id_t id, unsigned long pruneRows);
bool prune(log_id_t id, unsigned long pruneRows, uid_t uid = AID_ROOT);
LogBufferElementCollection::iterator erase(
LogBufferElementCollection::iterator it, bool coalesce = false);
// Returns an iterator to the oldest element for a given log type, or mLogElements.end() if
// there are no logs for the given log type. Requires mLogElementsLock to be held.
LogBufferElementCollection::iterator GetOldest(log_id_t log_id);
LogTags* tags_;
PruneList* prune_;
// Keeps track of the iterator to the oldest log message of a given log type, as an
// optimization when pruning logs. Use GetOldest() to retrieve.
std::optional<LogBufferElementCollection::iterator> oldest_[LOG_ID_MAX];
};