DnsEvent.java revision 4b6dfc2ef54723768a67887ce2a42d4f8f64d0f4 
1/*
2 * Copyright (C) 2016 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
17package android.net.metrics;
18
19import android.annotation.SystemApi;
20import android.os.Parcel;
21import android.os.Parcelable;
22
23/**
24 * {@hide}
25 */
26@SystemApi
27final public class DnsEvent extends IpConnectivityEvent implements Parcelable {
28    public final int netId;
29
30    // The event type is currently only 1 or 2, so we store it as a byte.
31    public final byte[] eventTypes;
32    // Current getaddrinfo codes go from 1 to EAI_MAX = 15. gethostbyname returns errno, but there
33    // are fewer than 255 errno values. So we store the result code in a byte as well.
34    public final byte[] returnCodes;
35    // The latency is an integer because a) short arrays aren't parcelable and b) a short can only
36    // store a maximum latency of 32757 or 65535 ms, which is too short for pathologically slow
37    // queries.
38    public final int[] latenciesMs;
39
40    private DnsEvent(int netId, byte[] eventTypes, byte[] returnCodes, int[] latenciesMs) {
41        this.netId = netId;
42        this.eventTypes = eventTypes;
43        this.returnCodes = returnCodes;
44        this.latenciesMs = latenciesMs;
45    }
46
47    private DnsEvent(Parcel in) {
48        this.netId = in.readInt();
49        this.eventTypes = in.createByteArray();
50        this.returnCodes = in.createByteArray();
51        this.latenciesMs = in.createIntArray();
52    }
53
54    @Override
55    public void writeToParcel(Parcel out, int flags) {
56        out.writeInt(netId);
57        out.writeByteArray(eventTypes);
58        out.writeByteArray(returnCodes);
59        out.writeIntArray(latenciesMs);
60    }
61
62    public int describeContents() {
63        return 0;
64    }
65
66    public static final Parcelable.Creator<DnsEvent> CREATOR = new Parcelable.Creator<DnsEvent>() {
67        @Override
68        public DnsEvent createFromParcel(Parcel in) {
69            return new DnsEvent(in);
70        }
71
72        @Override
73        public DnsEvent[] newArray(int size) {
74            return new DnsEvent[size];
75        }
76    };
77
78    public static void logEvent(
79            int netId, byte[] eventTypes, byte[] returnCodes, int[] latenciesMs) {
80        logEvent(IPCE_DNS_LOOKUPS, new DnsEvent(netId, eventTypes, returnCodes, latenciesMs));
81    }
82}
83