1/*
2 * Copyright (C) 2017 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.backup.transport;
18
19import android.annotation.IntDef;
20import android.annotation.Nullable;
21import android.os.DeadObjectException;
22import android.util.Log;
23import android.util.Slog;
24
25import com.android.internal.backup.IBackupTransport;
26
27import java.lang.annotation.Retention;
28import java.lang.annotation.RetentionPolicy;
29
30/** Utility methods for transport-related operations. */
31public class TransportUtils {
32    private static final String TAG = "TransportUtils";
33
34    /**
35     * Throws {@link TransportNotAvailableException} if {@param transport} is null. The semantics is
36     * similar to a {@link DeadObjectException} coming from a dead transport binder.
37     */
38    public static IBackupTransport checkTransportNotNull(@Nullable IBackupTransport transport)
39            throws TransportNotAvailableException {
40        if (transport == null) {
41            log(Priority.ERROR, TAG, "Transport not available");
42            throw new TransportNotAvailableException();
43        }
44        return transport;
45    }
46
47    static void log(@Priority int priority, String tag, String message) {
48        if (priority == Priority.WTF) {
49            Slog.wtf(tag, message);
50        } else if (Log.isLoggable(tag, priority)) {
51            Slog.println(priority, tag, message);
52        }
53    }
54
55    static String formatMessage(@Nullable String prefix, @Nullable String caller, String message) {
56        StringBuilder string = new StringBuilder();
57        if (prefix != null) {
58            string.append(prefix).append(" ");
59        }
60        if (caller != null) {
61            string.append("[").append(caller).append("] ");
62        }
63        return string.append(message).toString();
64    }
65
66    /**
67     * Create our own constants so we can log WTF using the same APIs. Except for {@link
68     * Priority#WTF} all the others have the same value, so can be used directly
69     */
70    @IntDef({Priority.VERBOSE, Priority.DEBUG, Priority.INFO, Priority.WARN, Priority.WTF})
71    @Retention(RetentionPolicy.SOURCE)
72    @interface Priority {
73        int VERBOSE = Log.VERBOSE;
74        int DEBUG = Log.DEBUG;
75        int INFO = Log.INFO;
76        int WARN = Log.WARN;
77        int ERROR = Log.ERROR;
78        int WTF = -1;
79    }
80
81    private TransportUtils() {}
82}
83