1/*
2 * Copyright (C) 2011 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 com.android.server.net;
18
19import android.net.NetworkIdentity;
20
21import java.io.DataInputStream;
22import java.io.DataOutputStream;
23import java.io.IOException;
24import java.util.HashSet;
25
26/**
27 * Identity of a {@code iface}, defined by the set of {@link NetworkIdentity}
28 * active on that interface.
29 *
30 * @hide
31 */
32public class NetworkIdentitySet extends HashSet<NetworkIdentity> {
33    private static final int VERSION_INIT = 1;
34    private static final int VERSION_ADD_ROAMING = 2;
35    private static final int VERSION_ADD_NETWORK_ID = 3;
36
37    public NetworkIdentitySet() {
38    }
39
40    public NetworkIdentitySet(DataInputStream in) throws IOException {
41        final int version = in.readInt();
42        final int size = in.readInt();
43        for (int i = 0; i < size; i++) {
44            if (version <= VERSION_INIT) {
45                final int ignored = in.readInt();
46            }
47            final int type = in.readInt();
48            final int subType = in.readInt();
49            final String subscriberId = readOptionalString(in);
50            final String networkId;
51            if (version >= VERSION_ADD_NETWORK_ID) {
52                networkId = readOptionalString(in);
53            } else {
54                networkId = null;
55            }
56            final boolean roaming;
57            if (version >= VERSION_ADD_ROAMING) {
58                roaming = in.readBoolean();
59            } else {
60                roaming = false;
61            }
62
63            add(new NetworkIdentity(type, subType, subscriberId, networkId, false));
64        }
65    }
66
67    public void writeToStream(DataOutputStream out) throws IOException {
68        out.writeInt(VERSION_ADD_NETWORK_ID);
69        out.writeInt(size());
70        for (NetworkIdentity ident : this) {
71            out.writeInt(ident.getType());
72            out.writeInt(ident.getSubType());
73            writeOptionalString(out, ident.getSubscriberId());
74            writeOptionalString(out, ident.getNetworkId());
75            out.writeBoolean(ident.getRoaming());
76        }
77    }
78
79    private static void writeOptionalString(DataOutputStream out, String value) throws IOException {
80        if (value != null) {
81            out.writeByte(1);
82            out.writeUTF(value);
83        } else {
84            out.writeByte(0);
85        }
86    }
87
88    private static String readOptionalString(DataInputStream in) throws IOException {
89        if (in.readByte() != 0) {
90            return in.readUTF();
91        } else {
92            return null;
93        }
94    }
95}
96