1 /*
2  * Copyright (C) 2016 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 
17 package com.android.tools.build.apkzlib.utils;
18 
19 import static org.junit.Assert.assertTrue;
20 
21 import com.android.testutils.TestResources;
22 import com.android.tools.build.apkzlib.zip.ZFile;
23 import com.google.common.base.Preconditions;
24 import com.google.common.io.ByteSource;
25 import com.google.common.io.Resources;
26 import java.io.ByteArrayInputStream;
27 import java.io.EOFException;
28 import java.io.File;
29 import java.io.IOException;
30 import java.io.RandomAccessFile;
31 import javax.annotation.Nonnull;
32 
33 /**
34  * Utility functions for tests.
35  */
36 public final class ApkZFileTestUtils {
37 
38     /**
39      * Reads a portion of a file to memory.
40      *
41      * @param file the file to read data from
42      * @param start the offset in the file to start reading
43      * @param length the number of bytes to read
44      * @return the bytes read
45      * @throws Exception failed to read the file
46      */
47     @Nonnull
readSegment(@onnull File file, long start, int length)48     public static byte[] readSegment(@Nonnull File file, long start, int length) throws Exception {
49         Preconditions.checkArgument(start >= 0, "start < 0");
50         Preconditions.checkArgument(length >= 0, "length < 0");
51 
52         byte data[];
53         try (RandomAccessFile raf = new RandomAccessFile(file, "r")) {
54             raf.seek(start);
55 
56             data = new byte[length];
57             int tot = 0;
58             while (tot < length) {
59                 int r = raf.read(data, tot, length - tot);
60                 if (r < 0) {
61                     throw new EOFException();
62                 }
63 
64                 tot += r;
65             }
66         }
67 
68         return data;
69     }
70 
71     /**
72      * Obtains the test resource with the given path.
73      *
74      * @param path the path
75      * @return the test resource
76      */
77     @Nonnull
getResource(@onnull String path)78     public static File getResource(@Nonnull String path) {
79         File resource = TestResources.getFile(ApkZFileTestUtils.class, path);
80         assertTrue(resource.exists());
81         return resource;
82     }
83 
84     /**
85      * Obtains the test resource with the given path.
86      *
87      * @param path the path
88      * @return the test resource
89      */
90     @Nonnull
getResourceBytes(@onnull String path)91     public static ByteSource getResourceBytes(@Nonnull String path) {
92         return Resources.asByteSource(Resources.getResource(ApkZFileTestUtils.class, path));
93     }
94 
95     /**
96      * Sleeps the current thread for enough time to ensure that the local file system had enough
97      * time to notice a "tick". This method is usually called in tests when it is necessary to
98      * ensure filesystem writes are detected through timestamp modification.
99      *
100      * @param currentTimestamp last timestamp read from disk
101      * @throws InterruptedException waiting interrupted
102      * @throws IOException issues creating a temporary file
103      */
waitForFileSystemTick(long currentTimestamp)104     public static void waitForFileSystemTick(long currentTimestamp)
105             throws InterruptedException, IOException {
106         while (getFreshTimestamp() <= currentTimestamp) {
107             Thread.sleep(100);
108         }
109     }
110 
111     /*
112      * Adds a basic compiled AndroidManifest to the given ZFile containing minSdkVersion equal 15
113      * and targetSdkVersion equal 25.
114      */
addAndroidManifest(ZFile zf)115     public static void addAndroidManifest(ZFile zf) throws IOException {
116         zf.add("AndroidManifest.xml", new ByteArrayInputStream(getAndroidManifest()));
117     }
118 
119     /*
120      * Provides a basic compiled AndroidManifest containing minSdkVersion equal 15 and
121      * targetSdkVersion equal 25.
122      */
getAndroidManifest()123     public static byte[] getAndroidManifest() throws IOException {
124         return ApkZFileTestUtils.getResourceBytes("/testData/packaging/AndroidManifest.xml").read();
125     }
126 
127     /**
128      * Obtains the timestamp of a newly-created file.
129      *
130      * @return the timestamp
131      * @throws IOException the I/O Exception
132      */
getFreshTimestamp()133     private static long getFreshTimestamp() throws IOException {
134         File notUsed = File.createTempFile(ApkZFileTestUtils.class.getName(), "waitForFSTick");
135         long freshTimestamp = notUsed.lastModified();
136         assertTrue(notUsed.delete());
137         return freshTimestamp;
138     }
139 }
140