1/*
2 * Copyright (C) 2013 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.firewall;
18
19import android.content.ComponentName;
20import android.content.Intent;
21import com.android.internal.util.XmlUtils;
22import org.xmlpull.v1.XmlPullParser;
23import org.xmlpull.v1.XmlPullParserException;
24
25import java.io.IOException;
26
27class NotFilter implements Filter {
28    private final Filter mChild;
29
30    private NotFilter(Filter child) {
31        mChild = child;
32    }
33
34    @Override
35    public boolean matches(IntentFirewall ifw, ComponentName resolvedComponent, Intent intent,
36            int callerUid, int callerPid, String resolvedType, int receivingUid) {
37        return !mChild.matches(ifw, resolvedComponent, intent, callerUid, callerPid, resolvedType,
38                receivingUid);
39    }
40
41    public static final FilterFactory FACTORY = new FilterFactory("not") {
42        @Override
43        public Filter newFilter(XmlPullParser parser)
44                throws IOException, XmlPullParserException {
45            Filter child = null;
46            int outerDepth = parser.getDepth();
47            while (XmlUtils.nextElementWithin(parser, outerDepth)) {
48                Filter filter = IntentFirewall.parseFilter(parser);
49                if (child == null) {
50                    child = filter;
51                } else {
52                    throw new XmlPullParserException(
53                            "<not> tag can only contain a single child filter.", parser, null);
54                }
55            }
56            return new NotFilter(child);
57        }
58    };
59}
60