1/*
2 * Copyright (C) 2010 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.am;
18
19import android.content.Intent;
20import android.os.Binder;
21import android.os.IBinder;
22import android.util.ArraySet;
23
24import com.google.android.collect.Sets;
25
26import java.io.PrintWriter;
27import java.util.Iterator;
28
29final class UriPermissionOwner {
30    final ActivityManagerService service;
31    final Object owner;
32
33    Binder externalToken;
34
35    private ArraySet<UriPermission> mReadPerms;
36    private ArraySet<UriPermission> mWritePerms;
37
38    class ExternalToken extends Binder {
39        UriPermissionOwner getOwner() {
40            return UriPermissionOwner.this;
41        }
42    }
43
44    UriPermissionOwner(ActivityManagerService service, Object owner) {
45        this.service = service;
46        this.owner = owner;
47    }
48
49    Binder getExternalTokenLocked() {
50        if (externalToken == null) {
51            externalToken = new ExternalToken();
52        }
53        return externalToken;
54    }
55
56    static UriPermissionOwner fromExternalToken(IBinder token) {
57        if (token instanceof ExternalToken) {
58            return ((ExternalToken)token).getOwner();
59        }
60        return null;
61    }
62
63    void removeUriPermissionsLocked() {
64        removeUriPermissionsLocked(Intent.FLAG_GRANT_READ_URI_PERMISSION
65                | Intent.FLAG_GRANT_WRITE_URI_PERMISSION);
66    }
67
68    void removeUriPermissionsLocked(int mode) {
69        removeUriPermissionLocked(null, mode);
70    }
71
72    void removeUriPermissionLocked(ActivityManagerService.GrantUri grantUri, int mode) {
73        if ((mode & Intent.FLAG_GRANT_READ_URI_PERMISSION) != 0
74                && mReadPerms != null) {
75            Iterator<UriPermission> it = mReadPerms.iterator();
76            while (it.hasNext()) {
77                UriPermission perm = it.next();
78                if (grantUri == null || grantUri.equals(perm.uri)) {
79                    perm.removeReadOwner(this);
80                    service.removeUriPermissionIfNeededLocked(perm);
81                    it.remove();
82                }
83            }
84            if (mReadPerms.isEmpty()) {
85                mReadPerms = null;
86            }
87        }
88        if ((mode & Intent.FLAG_GRANT_WRITE_URI_PERMISSION) != 0
89                && mWritePerms != null) {
90            Iterator<UriPermission> it = mWritePerms.iterator();
91            while (it.hasNext()) {
92                UriPermission perm = it.next();
93                if (grantUri == null || grantUri.equals(perm.uri)) {
94                    perm.removeWriteOwner(this);
95                    service.removeUriPermissionIfNeededLocked(perm);
96                    it.remove();
97                }
98            }
99            if (mWritePerms.isEmpty()) {
100                mWritePerms = null;
101            }
102        }
103    }
104
105    public void addReadPermission(UriPermission perm) {
106        if (mReadPerms == null) {
107            mReadPerms = Sets.newArraySet();
108        }
109        mReadPerms.add(perm);
110    }
111
112    public void addWritePermission(UriPermission perm) {
113        if (mWritePerms == null) {
114            mWritePerms = Sets.newArraySet();
115        }
116        mWritePerms.add(perm);
117    }
118
119    public void removeReadPermission(UriPermission perm) {
120        mReadPerms.remove(perm);
121        if (mReadPerms.isEmpty()) {
122            mReadPerms = null;
123        }
124    }
125
126    public void removeWritePermission(UriPermission perm) {
127        mWritePerms.remove(perm);
128        if (mWritePerms.isEmpty()) {
129            mWritePerms = null;
130        }
131    }
132
133    public void dump(PrintWriter pw, String prefix) {
134        if (mReadPerms != null) {
135            pw.print(prefix); pw.print("readUriPermissions="); pw.println(mReadPerms);
136        }
137        if (mWritePerms != null) {
138            pw.print(prefix); pw.print("writeUriPermissions="); pw.println(mWritePerms);
139        }
140    }
141
142    @Override
143    public String toString() {
144        return owner.toString();
145    }
146}
147