blob: 203318d91af566f65654f48e36e63a7b425ecef0 [file] [log] [blame]
* Copyright (C) 2017 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
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* See the License for the specific language governing permissions and
* limitations under the License.
#ifndef _LOGD_LOG_TAGS_H__
#define _LOGD_LOG_TAGS_H__
#include <string>
#include <unordered_map>
#include <unordered_set>
#include <utils/RWLock.h>
class LogTags {
// This lock protects all the unordered_map accesses below. It
// is a reader/writer lock so that contentions are kept to a
// minimum since writes are rare, even administratably when
// reads are extended. Resist the temptation to use the writer
// lock to protect anything outside the following unordered_maps
// as that would increase the reader contentions. Use a separate
// mutex to protect the other entities.
android::RWLock rwlock;
// key is Name + "+" + Format
std::unordered_map<std::string, uint32_t> key2tag;
typedef std::unordered_map<std::string, uint32_t>::const_iterator
// Allows us to manage access permissions based on uid registrants
// Global entries are specifically erased.
typedef std::unordered_set<uid_t> uid_list;
std::unordered_map<uint32_t, uid_list> tag2uid;
typedef std::unordered_map<uint32_t, uid_list>::const_iterator
std::unordered_map<uint32_t, std::string> tag2name;
typedef std::unordered_map<uint32_t, std::string>::const_iterator
std::unordered_map<uint32_t, std::string> tag2format;
typedef std::unordered_map<uint32_t, std::string>::const_iterator
static const size_t max_per_uid = 256; // Put a cap on the tags per uid
std::unordered_map<uid_t, size_t> uid2count;
typedef std::unordered_map<uid_t, size_t>::const_iterator
// Dynamic entries are assigned
std::unordered_map<uint32_t, size_t> tag2total;
typedef std::unordered_map<uint32_t, size_t>::const_iterator
// emplace unique tag
uint32_t nameToTag(uid_t uid, const char* name, const char* format);
// find unique or associated tag
uint32_t nameToTag_locked(const std::string& name, const char* format,
bool& unique);
// Record expected file watermarks to detect corruption.
std::unordered_map<std::string, size_t> file2watermark;
typedef std::unordered_map<std::string, size_t>::const_iterator
void ReadPersistEventLogTags();
// format helpers
// format a single entry, does not need object data
static std::string formatEntry(uint32_t tag, uid_t uid, const char* name,
const char* format);
// caller locks, database lookup, authenticate against uid
std::string formatEntry_locked(uint32_t tag, uid_t uid,
bool authenticate = true);
bool RebuildFileEventLogTags(const char* filename, bool warn = true);
void AddEventLogTags(uint32_t tag, uid_t uid, const std::string& Name,
const std::string& Format, const char* source = NULL,
bool warn = false);
void WriteDynamicEventLogTags(uint32_t tag, uid_t uid);
void WriteDebugEventLogTags(uint32_t tag, uid_t uid);
// push tag details to persistent storage
void WritePersistEventLogTags(uint32_t tag, uid_t uid = AID_ROOT,
const char* source = NULL);
static const uint32_t emptyTag = uint32_t(-1);
static const char system_event_log_tags[];
static const char dynamic_event_log_tags[];
// Only for userdebug and eng
static const char debug_event_log_tags[];
void WritePmsgEventLogTags(uint32_t tag, uid_t uid = AID_ROOT);
void ReadFileEventLogTags(const char* filename, bool warn = true);
// reverse lookup from tag
const char* tagToName(uint32_t tag) const;
const char* tagToFormat(uint32_t tag) const;
std::string formatEntry(uint32_t tag, uid_t uid);
// find associated tag
uint32_t nameToTag(const char* name) const;
// emplace tag if necessary, provide event-log-tag formated output in string
std::string formatGetEventTag(uid_t uid, const char* name,
const char* format);
#endif // _LOGD_LOG_TAGS_H__