LogBufferElement.h revision 81b3eabc49736b89c4f99940f79785074955eaa5 
1/*
2 * Copyright (C) 2012-2014 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#ifndef _LOGD_LOG_BUFFER_ELEMENT_H__
18#define _LOGD_LOG_BUFFER_ELEMENT_H__
19
20#include <stdatomic.h>
21#include <stdlib.h>
22#include <sys/types.h>
23
24#include <sysutils/SocketClient.h>
25#include <log/log.h>
26#include <log/log_read.h>
27
28// Hijack this header as a common include file used by most all sources
29// to report some utilities defined here and there.
30
31namespace android {
32
33// Furnished in main.cpp. Caller must own and free returned value
34// This function is designed for a single caller and is NOT thread-safe
35char *uidToName(uid_t uid);
36
37}
38
39static inline bool worstUidEnabledForLogid(log_id_t id) {
40    return (id != LOG_ID_CRASH) && (id != LOG_ID_EVENTS);
41}
42
43class LogBufferElement {
44    const log_id_t mLogId;
45    const uid_t mUid;
46    const pid_t mPid;
47    const pid_t mTid;
48    char *mMsg;
49    union {
50        const unsigned short mMsgLen; // mMSg != NULL
51        unsigned short mDropped;      // mMsg == NULL
52    };
53    const uint64_t mSequence;
54    const log_time mRealTime;
55    static atomic_int_fast64_t sequence;
56
57    // assumption: mMsg == NULL
58    size_t populateDroppedMessage(char *&buffer, bool privileged);
59
60public:
61    LogBufferElement(log_id_t log_id, log_time realtime,
62                     uid_t uid, pid_t pid, pid_t tid,
63                     const char *msg, unsigned short len);
64    virtual ~LogBufferElement();
65
66    log_id_t getLogId() const { return mLogId; }
67    uid_t getUid(void) const { return mUid; }
68    pid_t getPid(void) const { return mPid; }
69    pid_t getTid(void) const { return mTid; }
70    unsigned short getDropped(void) const { return mMsg ? 0 : mDropped; }
71    unsigned short setDropped(unsigned short value) {
72        if (mMsg) {
73            free(mMsg);
74            mMsg = NULL;
75        }
76        return mDropped = value;
77    }
78    unsigned short getMsgLen() const { return mMsg ? mMsgLen : 0; }
79    uint64_t getSequence(void) const { return mSequence; }
80    static uint64_t getCurrentSequence(void) { return sequence.load(memory_order_relaxed); }
81    log_time getRealTime(void) const { return mRealTime; }
82
83    static const uint64_t FLUSH_ERROR;
84    uint64_t flushTo(SocketClient *writer);
85};
86
87#endif
88