1/*
2 * Copyright (C) 2015 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.preload;
18
19import com.android.ddmlib.AndroidDebugBridge;
20import com.android.ddmlib.AndroidDebugBridge.IClientChangeListener;
21import com.android.ddmlib.Client;
22import com.android.ddmlib.IDevice;
23
24/**
25 * Helper class for common communication with a Client (the ddms name for a running application).
26 *
27 * Instances take a default timeout parameter that's applied to all functions without explicit
28 * timeout. Timeouts are in milliseconds.
29 */
30public class ClientUtils {
31
32    private int defaultTimeout;
33
34    public ClientUtils() {
35        this(10000);
36    }
37
38    public ClientUtils(int defaultTimeout) {
39        this.defaultTimeout = defaultTimeout;
40    }
41
42    /**
43     * Shortcut for findClient with default timeout.
44     */
45    public Client findClient(IDevice device, String processName, int processPid) {
46        return findClient(device, processName, processPid, defaultTimeout);
47    }
48
49    /**
50     * Find the client with the given process name or process id. The name takes precedence over
51     * the process id (if valid). Stop looking after the given timeout.
52     *
53     * @param device The device to communicate with.
54     * @param processName The name of the process. May be null.
55     * @param processPid The pid of the process. Values less than or equal to zero are ignored.
56     * @param timeout The amount of milliseconds to wait, at most.
57     * @return The client, if found. Otherwise null.
58     */
59    public Client findClient(IDevice device, String processName, int processPid, int timeout) {
60        WaitForClient wfc = new WaitForClient(device, processName, processPid, timeout);
61        return wfc.get();
62    }
63
64    /**
65     * Shortcut for findAllClients with default timeout.
66     */
67    public Client[] findAllClients(IDevice device) {
68        return findAllClients(device, defaultTimeout);
69    }
70
71    /**
72     * Retrieve all clients known to the given device. Wait at most the given timeout.
73     *
74     * @param device The device to investigate.
75     * @param timeout The amount of milliseconds to wait, at most.
76     * @return An array of clients running on the given device. May be null depending on the
77     *         device implementation.
78     */
79    public Client[] findAllClients(IDevice device, int timeout) {
80        if (device.hasClients()) {
81            return device.getClients();
82        }
83        WaitForClients wfc = new WaitForClients(device, timeout);
84        return wfc.get();
85    }
86
87    private static class WaitForClient implements IClientChangeListener {
88
89        private IDevice device;
90        private String processName;
91        private int processPid;
92        private long timeout;
93        private Client result;
94
95        public WaitForClient(IDevice device, String processName, int processPid, long timeout) {
96            this.device = device;
97            this.processName = processName;
98            this.processPid = processPid;
99            this.timeout = timeout;
100            this.result = null;
101        }
102
103        public Client get() {
104            synchronized (this) {
105                AndroidDebugBridge.addClientChangeListener(this);
106
107                // Maybe it's already there.
108                if (result == null) {
109                    result = searchForClient(device);
110                }
111
112                if (result == null) {
113                    try {
114                        wait(timeout);
115                    } catch (InterruptedException e) {
116                        // Note: doesn't guard for spurious wakeup.
117                    }
118                }
119            }
120
121            AndroidDebugBridge.removeClientChangeListener(this);
122            return result;
123        }
124
125        private Client searchForClient(IDevice device) {
126            if (processName != null) {
127                Client tmp = device.getClient(processName);
128                if (tmp != null) {
129                    return tmp;
130                }
131            }
132            if (processPid > 0) {
133                String name = device.getClientName(processPid);
134                if (name != null && !name.isEmpty()) {
135                    Client tmp = device.getClient(name);
136                    if (tmp != null) {
137                        return tmp;
138                    }
139                }
140            }
141            if (processPid > 0) {
142                // Try manual search.
143                for (Client cl : device.getClients()) {
144                    if (cl.getClientData().getPid() == processPid
145                            && cl.getClientData().getClientDescription() != null) {
146                        return cl;
147                    }
148                }
149            }
150            return null;
151        }
152
153        private boolean isTargetClient(Client c) {
154            if (processPid > 0 && c.getClientData().getPid() == processPid) {
155                return true;
156            }
157            if (processName != null
158                    && processName.equals(c.getClientData().getClientDescription())) {
159                return true;
160            }
161            return false;
162        }
163
164        @Override
165        public void clientChanged(Client arg0, int arg1) {
166            synchronized (this) {
167                if ((arg1 & Client.CHANGE_INFO) != 0 && (arg0.getDevice() == device)) {
168                    if (isTargetClient(arg0)) {
169                        result = arg0;
170                        notifyAll();
171                    }
172                }
173            }
174        }
175    }
176
177    private static class WaitForClients implements IClientChangeListener {
178
179        private IDevice device;
180        private long timeout;
181
182        public WaitForClients(IDevice device, long timeout) {
183            this.device = device;
184            this.timeout = timeout;
185        }
186
187        public Client[] get() {
188            synchronized (this) {
189                AndroidDebugBridge.addClientChangeListener(this);
190
191                if (device.hasClients()) {
192                    return device.getClients();
193                }
194
195                try {
196                    wait(timeout); // Note: doesn't guard for spurious wakeup.
197                } catch (InterruptedException exc) {
198                }
199
200                // We will be woken up when the first client data arrives. Sleep a little longer
201                // to give (hopefully all of) the rest of the clients a chance to become available.
202                // Note: a loop with timeout is brittle as well and complicated, just accept this
203                //       for now.
204                try {
205                    Thread.sleep(500);
206                } catch (InterruptedException exc) {
207                }
208            }
209
210            AndroidDebugBridge.removeClientChangeListener(this);
211
212            return device.getClients();
213        }
214
215        @Override
216        public void clientChanged(Client arg0, int arg1) {
217            synchronized (this) {
218                if ((arg1 & Client.CHANGE_INFO) != 0 && (arg0.getDevice() == device)) {
219                    notifyAll();
220                }
221            }
222        }
223    }
224}
225