Yohann Roussel | 602c6ca | 2014-03-28 17:35:02 +0100 | [diff] [blame] | 1 | /* |
| 2 | * Licensed to the Apache Software Foundation (ASF) under one or more |
| 3 | * contributor license agreements. See the NOTICE file distributed with |
| 4 | * this work for additional information regarding copyright ownership. |
| 5 | * The ASF licenses this file to You under the Apache License, Version 2.0 |
| 6 | * (the "License"); you may not use this file except in compliance with |
| 7 | * the License. You may obtain a copy of the License at |
| 8 | * |
| 9 | * http://www.apache.org/licenses/LICENSE-2.0 |
| 10 | * |
| 11 | * Unless required by applicable law or agreed to in writing, software |
| 12 | * distributed under the License is distributed on an "AS IS" BASIS, |
| 13 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 14 | * See the License for the specific language governing permissions and |
| 15 | * limitations under the License. |
| 16 | */ |
| 17 | /* Apache Harmony HEADER because the code in this class comes mostly from ZipFile, ZipEntry and |
| 18 | * ZipConstants from android libcore. |
| 19 | */ |
| 20 | |
| 21 | package android.support.multidex; |
| 22 | |
| 23 | import java.io.IOException; |
| 24 | import java.nio.ByteBuffer; |
| 25 | import java.nio.charset.Charset; |
| 26 | import java.util.Calendar; |
| 27 | import java.util.GregorianCalendar; |
| 28 | import java.util.zip.ZipEntry; |
| 29 | import java.util.zip.ZipException; |
| 30 | |
| 31 | class ZipEntryReader { |
| 32 | static final Charset UTF_8 = Charset.forName("UTF-8"); |
| 33 | /** |
| 34 | * General Purpose Bit Flags, Bit 0. |
| 35 | * If set, indicates that the file is encrypted. |
| 36 | */ |
| 37 | private static final int GPBF_ENCRYPTED_FLAG = 1 << 0; |
| 38 | |
| 39 | /** |
| 40 | * Supported General Purpose Bit Flags Mask. |
| 41 | * Bit mask of bits not supported. |
| 42 | * Note: The only bit that we will enforce at this time |
| 43 | * is the encrypted bit. Although other bits are not supported, |
| 44 | * we must not enforce them as this could break some legitimate |
| 45 | * use cases (See http://b/8617715). |
| 46 | */ |
| 47 | private static final int GPBF_UNSUPPORTED_MASK = GPBF_ENCRYPTED_FLAG; |
| 48 | private static final long CENSIG = 0x2014b50; |
| 49 | |
| 50 | static ZipEntry readEntry(ByteBuffer in) throws IOException { |
| 51 | |
| 52 | int sig = in.getInt(); |
| 53 | if (sig != CENSIG) { |
| 54 | throw new ZipException("Central Directory Entry not found"); |
| 55 | } |
| 56 | |
| 57 | in.position(8); |
| 58 | int gpbf = in.getShort() & 0xffff; |
| 59 | |
| 60 | if ((gpbf & GPBF_UNSUPPORTED_MASK) != 0) { |
| 61 | throw new ZipException("Invalid General Purpose Bit Flag: " + gpbf); |
| 62 | } |
| 63 | |
| 64 | int compressionMethod = in.getShort() & 0xffff; |
| 65 | int time = in.getShort() & 0xffff; |
| 66 | int modDate = in.getShort() & 0xffff; |
| 67 | |
| 68 | // These are 32-bit values in the file, but 64-bit fields in this object. |
| 69 | long crc = ((long) in.getInt()) & 0xffffffffL; |
| 70 | long compressedSize = ((long) in.getInt()) & 0xffffffffL; |
| 71 | long size = ((long) in.getInt()) & 0xffffffffL; |
| 72 | |
| 73 | int nameLength = in.getShort() & 0xffff; |
| 74 | int extraLength = in.getShort() & 0xffff; |
| 75 | int commentByteCount = in.getShort() & 0xffff; |
| 76 | |
| 77 | // This is a 32-bit value in the file, but a 64-bit field in this object. |
| 78 | in.position(42); |
| 79 | long localHeaderRelOffset = ((long) in.getInt()) & 0xffffffffL; |
| 80 | |
| 81 | byte[] nameBytes = new byte[nameLength]; |
| 82 | in.get(nameBytes, 0, nameBytes.length); |
| 83 | String name = new String(nameBytes, 0, nameBytes.length, UTF_8); |
| 84 | |
| 85 | ZipEntry entry = new ZipEntry(name); |
| 86 | entry.setMethod(compressionMethod); |
| 87 | entry.setTime(getTime(time, modDate)); |
| 88 | |
| 89 | entry.setCrc(crc); |
| 90 | entry.setCompressedSize(compressedSize); |
| 91 | entry.setSize(size); |
| 92 | |
| 93 | // The RI has always assumed UTF-8. (If GPBF_UTF8_FLAG isn't set, the encoding is |
| 94 | // actually IBM-437.) |
| 95 | if (commentByteCount > 0) { |
| 96 | byte[] commentBytes = new byte[commentByteCount]; |
| 97 | in.get(commentBytes, 0, commentByteCount); |
| 98 | entry.setComment(new String(commentBytes, 0, commentBytes.length, UTF_8)); |
| 99 | } |
| 100 | |
| 101 | if (extraLength > 0) { |
| 102 | byte[] extra = new byte[extraLength]; |
| 103 | in.get(extra, 0, extraLength); |
| 104 | entry.setExtra(extra); |
| 105 | } |
| 106 | |
| 107 | return entry; |
| 108 | |
| 109 | } |
| 110 | |
| 111 | private static long getTime(int time, int modDate) { |
| 112 | GregorianCalendar cal = new GregorianCalendar(); |
| 113 | cal.set(Calendar.MILLISECOND, 0); |
| 114 | cal.set(1980 + ((modDate >> 9) & 0x7f), ((modDate >> 5) & 0xf) - 1, |
| 115 | modDate & 0x1f, (time >> 11) & 0x1f, (time >> 5) & 0x3f, |
| 116 | (time & 0x1f) << 1); |
| 117 | return cal.getTime().getTime(); |
| 118 | } |
| 119 | |
| 120 | } |