platform_system_core/logd/LogUtils.h

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/*
* Copyright (C) 2012-2015 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.
*/
#ifndef _LOGD_LOG_UTILS_H__
#define _LOGD_LOG_UTILS_H__
#include <sys/cdefs.h>
#include <sys/types.h>
#include <utils/FastStrcmp.h>
#include <private/android_logger.h>
#include <sysutils/SocketClient.h>
// Hijack this header as a common include file used by most all sources
// to report some utilities defined here and there.
namespace android {
// Furnished in main.cpp. Caller must own and free returned value
char *uidToName(uid_t uid);
void prdebug(const char *fmt, ...) __printflike(1, 2);
// Furnished in LogStatistics.cpp. Caller must own and free returned value
char *pidToName(pid_t pid);
char *tidToName(pid_t tid);
// Furnished in main.cpp. Thread safe.
liblog: logd: Add android_lookupEventTag_len() Allows us to mitigate the impact of MAP_PRIVATE and copy on write by calling android_lookupEventTag_len instead of android_lookupEventTag, and delaying the copy on write impact to the later. We return a string length in a supplied location along with the string pointer with android_lookupEventTag_len(const EventTagMap* map, size_t* len, int tag). The string is not guaranteed to be nul terminated. Since android_lookupEventTag() called even once can cause the memory impact, we will mark it as deprecated, but we currently have no timeframe for removal since this is a very old interface. Add an API for __android_log_is_loggable_len() that accepts the non null terminated content and fixup callers that would gain because the length is known prior to the call either in the compiler or at runtime. Tackle transition to android_lookupEventTag_len() and fixup callers. On any application that performs logging (eg: com.android.phone) /proc/<pid>/smaps before: xxxxxxxxxx-xxxxxxxxxx rw-p 00000000 fd:00 463 /system/etc/event-log-tags Size: 20 kB Rss: 20 kB Pss: 1 kB Shared_Clean: 0 kB Shared_Dirty: 20 kB Private_Clean: 0 kB Private_Dirty: 0 kB Referenced: 0 kB Anonymous: 20 kB AnonHugePages: 0 kB Swap: 0 kB SwapPss: 0 kB KernelPageSize: 4 kB MMUPageSize: 4 kB Locked: 0 kB VmFlags: rd wr mr mw me ac /proc/<pid>/smaps after: xxxxxxxxxx-xxxxxxxxxx rw-p 00000000 fd:00 1773 /system/etc/event-log-tags Size: 20 kB Rss: 20 kB Pss: 1 kB Shared_Clean: 20 kB (was 0kB) Shared_Dirty: 0 kB (was 20kB) Private_Clean: 0 kB Private_Dirty: 0 kB Referenced: 20 kB (was 0kB) Anonymous: 0 kB (was 20kB) AnonHugePages: 0 kB Swap: 0 kB SwapPss: 0 kB KernelPageSize: 4 kB MMUPageSize: 4 kB Locked: 0 kB VmFlags: rd wr mr mw me ac Added liblog-unit-tests --gtest_filter=liblog.event_log_tags to check for Shared_Clean: to not be 0 and Anonymous: to be 0 for all processes referencing event-log-tags. Which can include multiple references to /system/etc/event-log-tags and future possible refs to /data/misc/logd/event-log-tags and /dev/event-log-tags. We want failure messages to help point to errant code using the deprecated interface. This change saves 1/4MB of memory or more on a typical system. Test: gTest liblog-unit-tests Bug: 31456426 Change-Id: I9e08e44d9092bd96fe704b5709242e7195281d33
2016-09-23 00:56:51 +08:00
const char *tagToName(size_t *len, uint32_t tag);
}
// Furnished in LogCommand.cpp
bool clientHasLogCredentials(uid_t uid, gid_t gid, pid_t pid);
bool clientHasLogCredentials(SocketClient *cli);
static inline bool worstUidEnabledForLogid(log_id_t id) {
return (id == LOG_ID_MAIN) || (id == LOG_ID_SYSTEM) ||
(id == LOG_ID_RADIO) || (id == LOG_ID_EVENTS);
}
#endif // _LOGD_LOG_UTILS_H__