Aurimas Liutikas | 88c7ff1 | 2023-08-10 12:42:26 -0700 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 2007 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 org.apache.harmony.dalvik.ddmc; |
| 18 | |
| 19 | import static android.annotation.SystemApi.Client.MODULE_LIBRARIES; |
| 20 | |
| 21 | import android.annotation.SystemApi; |
| 22 | import android.compat.annotation.UnsupportedAppUsage; |
| 23 | import java.nio.ByteBuffer; |
| 24 | import java.nio.ByteOrder; |
| 25 | |
| 26 | /** |
| 27 | * Handle a chunk of data sent from a DDM server. |
| 28 | * |
| 29 | * To handle a chunk type, sub-class {@link ChunkHandler} and register your class |
| 30 | * with {@link DdmServer}. |
| 31 | * |
| 32 | * @hide |
| 33 | */ |
| 34 | @SystemApi(client = MODULE_LIBRARIES) |
| 35 | public abstract class ChunkHandler { |
| 36 | |
| 37 | /** |
| 38 | * Byte order of the data in the chunk. |
| 39 | * |
| 40 | * @hide |
| 41 | */ |
| 42 | @UnsupportedAppUsage |
| 43 | @SystemApi(client = MODULE_LIBRARIES) |
| 44 | public static final ByteOrder CHUNK_ORDER = ByteOrder.BIG_ENDIAN; |
| 45 | |
| 46 | /** |
| 47 | * @hide |
| 48 | */ |
| 49 | public static final int CHUNK_FAIL = type("FAIL"); |
| 50 | |
| 51 | /** |
| 52 | * Constructs chunk handler. |
| 53 | * |
| 54 | * @hide |
| 55 | */ |
| 56 | @SystemApi(client = MODULE_LIBRARIES) |
| 57 | public ChunkHandler() {} |
| 58 | |
| 59 | /** |
| 60 | * Called when the DDM server connects. The handler is allowed to |
| 61 | * send messages to the server. |
| 62 | * |
| 63 | * @hide |
| 64 | */ |
| 65 | @SystemApi(client = MODULE_LIBRARIES) |
| 66 | public abstract void onConnected(); |
| 67 | |
| 68 | /** |
| 69 | * Called when the DDM server disconnects. Can be used to disable |
| 70 | * periodic transmissions or clean up saved state. |
| 71 | * |
| 72 | * @hide |
| 73 | */ |
| 74 | @SystemApi(client = MODULE_LIBRARIES) |
| 75 | public abstract void onDisconnected(); |
| 76 | |
| 77 | /** |
| 78 | * Handle a single chunk of data. {@code request} includes the type and |
| 79 | * the chunk payload. |
| 80 | * |
| 81 | * Returns a response in a {@link Chunk}. |
| 82 | * |
| 83 | * @param request chunk type and payload |
| 84 | * @return {@link Chunk} with response |
| 85 | * |
| 86 | * @hide |
| 87 | */ |
| 88 | @SystemApi(client = MODULE_LIBRARIES) |
| 89 | public abstract Chunk handleChunk(Chunk request); |
| 90 | |
| 91 | /** |
| 92 | * Create a FAIL chunk. The {@link #handleChunk(Chunk)} methods can use this to |
| 93 | * return an error message when they are not able to process a chunk. |
| 94 | * |
| 95 | * @param errorCode arbitrary number to distinguish error |
| 96 | * @param msg error message |
| 97 | * @return {@link Chunk} with response |
| 98 | * |
| 99 | * @hide |
| 100 | */ |
| 101 | @SystemApi(client = MODULE_LIBRARIES) |
| 102 | public static Chunk createFailChunk(int errorCode, String msg) { |
| 103 | if (msg == null) |
| 104 | msg = ""; |
| 105 | |
| 106 | ByteBuffer out = ByteBuffer.allocate(8 + msg.length() * 2); |
| 107 | out.order(ChunkHandler.CHUNK_ORDER); |
| 108 | out.putInt(errorCode); |
| 109 | out.putInt(msg.length()); |
| 110 | final int len = msg.length(); |
| 111 | for (int i = 0; i < len; i++) { |
| 112 | out.putChar(msg.charAt(i)); |
| 113 | } |
| 114 | |
| 115 | return new Chunk(CHUNK_FAIL, out); |
| 116 | } |
| 117 | |
| 118 | /** |
| 119 | * Utility function to wrap a {@link ByteBuffer} around a {@link Chunk}. |
| 120 | * |
| 121 | * @param request chunk to be wrapped |
| 122 | * @return {@link ByteBuffer} wrapping data from the given chunk |
| 123 | * |
| 124 | * @hide |
| 125 | */ |
| 126 | @SystemApi(client = MODULE_LIBRARIES) |
| 127 | public static ByteBuffer wrapChunk(Chunk request) { |
| 128 | ByteBuffer in; |
| 129 | |
| 130 | in = ByteBuffer.wrap(request.data, request.offset, request.length); |
| 131 | in.order(CHUNK_ORDER); |
| 132 | return in; |
| 133 | } |
| 134 | |
| 135 | /** |
| 136 | * Convert a 4-character string to a 32-bit type. |
| 137 | * |
| 138 | * @hide |
| 139 | */ |
| 140 | @SystemApi(client = MODULE_LIBRARIES) |
| 141 | public static int type(String typeName) { |
| 142 | if (typeName.length() != 4) { |
| 143 | throw new IllegalArgumentException("Bad type name: " + typeName); |
| 144 | } |
| 145 | int result = 0; |
| 146 | for (int i = 0; i < 4; ++i) { |
| 147 | result = ((result << 8) | (typeName.charAt(i) & 0xff)); |
| 148 | } |
| 149 | return result; |
| 150 | } |
| 151 | |
| 152 | /** |
| 153 | * Convert an integer type to a 4-character string. |
| 154 | * |
| 155 | * @hide |
| 156 | */ |
| 157 | @SystemApi(client = MODULE_LIBRARIES) |
| 158 | public static String name(int type) |
| 159 | { |
| 160 | char[] ascii = new char[4]; |
| 161 | |
| 162 | ascii[0] = (char) ((type >> 24) & 0xff); |
| 163 | ascii[1] = (char) ((type >> 16) & 0xff); |
| 164 | ascii[2] = (char) ((type >> 8) & 0xff); |
| 165 | ascii[3] = (char) (type & 0xff); |
| 166 | |
| 167 | return new String(ascii); |
| 168 | } |
| 169 | } |