| /* |
| * Copyright (C) 2006 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| package com.android.internal.telephony.gsm.stk; |
| |
| import java.util.ArrayList; |
| import java.util.List; |
| |
| |
| /** |
| * Class for representing COMPREHENSION-TLV objects. |
| * |
| * @see "ETSI TS 101 220 subsection 7.1.1" |
| * |
| * {@hide} |
| */ |
| class ComprehensionTlv { |
| private int mTag; |
| private boolean mCr; |
| private int mLength; |
| private int mValueIndex; |
| private byte[] mRawValue; |
| |
| /** |
| * Constructor. Private on purpose. Use |
| * {@link #decodeMany(byte[], int) decodeMany} or |
| * {@link #decode(byte[], int) decode} method. |
| * |
| * @param tag The tag for this object |
| * @param cr Comprehension Required flag |
| * @param length Length of the value |
| * @param data Byte array containing the value |
| * @param valueIndex Index in data at which the value starts |
| */ |
| protected ComprehensionTlv(int tag, boolean cr, int length, byte[] data, |
| int valueIndex) { |
| mTag = tag; |
| mCr = cr; |
| mLength = length; |
| mValueIndex = valueIndex; |
| mRawValue = data; |
| } |
| |
| public int getTag() { |
| return mTag; |
| } |
| |
| public boolean isComprehensionRequired() { |
| return mCr; |
| } |
| |
| public int getLength() { |
| return mLength; |
| } |
| |
| public int getValueIndex() { |
| return mValueIndex; |
| } |
| |
| public byte[] getRawValue() { |
| return mRawValue; |
| } |
| |
| /** |
| * Parses a list of COMPREHENSION-TLV objects from a byte array. |
| * |
| * @param data A byte array containing data to be parsed |
| * @param startIndex Index in data at which to start parsing |
| * @return A list of COMPREHENSION-TLV objects parsed |
| * @throws ResultException |
| */ |
| public static List<ComprehensionTlv> decodeMany(byte[] data, int startIndex) |
| throws ResultException { |
| ArrayList<ComprehensionTlv> items = new ArrayList<ComprehensionTlv>(); |
| int endIndex = data.length; |
| while (startIndex < endIndex) { |
| ComprehensionTlv ctlv = ComprehensionTlv.decode(data, startIndex); |
| items.add(ctlv); |
| startIndex = ctlv.mValueIndex + ctlv.mLength; |
| } |
| |
| return items; |
| } |
| |
| /** |
| * Parses an COMPREHENSION-TLV object from a byte array. |
| * |
| * @param data A byte array containing data to be parsed |
| * @param startIndex Index in data at which to start parsing |
| * @return A COMPREHENSION-TLV object parsed |
| * @throws ResultException |
| */ |
| public static ComprehensionTlv decode(byte[] data, int startIndex) |
| throws ResultException { |
| try { |
| int curIndex = startIndex; |
| int endIndex = data.length; |
| |
| /* tag */ |
| int tag; |
| boolean cr; // Comprehension required flag |
| int temp = data[curIndex++] & 0xff; |
| switch (temp) { |
| case 0: |
| case 0xff: |
| case 0x80: |
| throw new ResultException(ResultCode.CMD_DATA_NOT_UNDERSTOOD); |
| |
| case 0x7f: // tag is in three-byte format |
| tag = ((data[curIndex] & 0xff) << 8) |
| | (data[curIndex + 1] & 0xff); |
| cr = (tag & 0x8000) != 0; |
| tag &= ~0x8000; |
| curIndex += 2; |
| break; |
| |
| default: // tag is in single-byte format |
| tag = temp; |
| cr = (tag & 0x80) != 0; |
| tag &= ~0x80; |
| break; |
| } |
| |
| /* length */ |
| int length; |
| temp = data[curIndex++] & 0xff; |
| if (temp < 0x80) { |
| length = temp; |
| } else if (temp == 0x81) { |
| length = data[curIndex++] & 0xff; |
| if (length < 0x80) { |
| throw new ResultException( |
| ResultCode.CMD_DATA_NOT_UNDERSTOOD); |
| } |
| } else if (temp == 0x82) { |
| length = ((data[curIndex] & 0xff) << 8) |
| | (data[curIndex + 1] & 0xff); |
| curIndex += 2; |
| if (length < 0x100) { |
| throw new ResultException( |
| ResultCode.CMD_DATA_NOT_UNDERSTOOD); |
| } |
| } else if (temp == 0x83) { |
| length = ((data[curIndex] & 0xff) << 16) |
| | ((data[curIndex + 1] & 0xff) << 8) |
| | (data[curIndex + 2] & 0xff); |
| curIndex += 3; |
| if (length < 0x10000) { |
| throw new ResultException( |
| ResultCode.CMD_DATA_NOT_UNDERSTOOD); |
| } |
| } else { |
| throw new ResultException(ResultCode.CMD_DATA_NOT_UNDERSTOOD); |
| } |
| |
| return new ComprehensionTlv(tag, cr, length, data, curIndex); |
| |
| } catch (IndexOutOfBoundsException e) { |
| throw new ResultException(ResultCode.CMD_DATA_NOT_UNDERSTOOD); |
| } |
| } |
| } |