1 /* 2 * Copyright (C) 2014 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.internal.telephony; 18 19 import android.content.res.Resources; 20 import android.content.res.XmlResourceParser; 21 import android.os.Build; 22 import android.telephony.Rlog; 23 import android.util.SparseIntArray; 24 25 import com.android.internal.telephony.cdma.sms.UserData; 26 import com.android.internal.util.XmlUtils; 27 28 public class Sms7BitEncodingTranslator { 29 private static final String TAG = "Sms7BitEncodingTranslator"; 30 private static final boolean DBG = Build.IS_DEBUGGABLE ; 31 private static boolean mIs7BitTranslationTableLoaded = false; 32 private static SparseIntArray mTranslationTable = null; 33 private static SparseIntArray mTranslationTableCommon = null; 34 private static SparseIntArray mTranslationTableGSM = null; 35 private static SparseIntArray mTranslationTableCDMA = null; 36 37 // Parser variables 38 private static final String XML_START_TAG = "SmsEnforce7BitTranslationTable"; 39 private static final String XML_TRANSLATION_TYPE_TAG = "TranslationType"; 40 private static final String XML_CHARACTOR_TAG = "Character"; 41 private static final String XML_FROM_TAG = "from"; 42 private static final String XML_TO_TAG = "to"; 43 44 /** 45 * Translates each message character that is not supported by GSM 7bit alphabet into a supported 46 * one. 47 * 48 * @param message message to be translated. 49 * @param isCdmaFormat true if cdma format should be used. 50 * @return translated message or null if some error occur. 51 */ translate(CharSequence message, boolean isCdmaFormat)52 public static String translate(CharSequence message, boolean isCdmaFormat) { 53 if (message == null) { 54 Rlog.w(TAG, "Null message can not be translated"); 55 return null; 56 } 57 58 int size = message.length(); 59 if (size <= 0) { 60 return ""; 61 } 62 63 if (!mIs7BitTranslationTableLoaded) { 64 mTranslationTableCommon = new SparseIntArray(); 65 mTranslationTableGSM = new SparseIntArray(); 66 mTranslationTableCDMA = new SparseIntArray(); 67 load7BitTranslationTableFromXml(); 68 mIs7BitTranslationTableLoaded = true; 69 } 70 71 if ((mTranslationTableCommon != null && mTranslationTableCommon.size() > 0) || 72 (mTranslationTableGSM != null && mTranslationTableGSM.size() > 0) || 73 (mTranslationTableCDMA != null && mTranslationTableCDMA.size() > 0)) { 74 char[] output = new char[size]; 75 for (int i = 0; i < size; i++) { 76 output[i] = translateIfNeeded(message.charAt(i), isCdmaFormat); 77 } 78 79 return String.valueOf(output); 80 } 81 82 return null; 83 } 84 85 /** 86 * Translates a single character into its corresponding acceptable one, if 87 * needed, based on GSM 7-bit alphabet 88 * 89 * @param c 90 * character to be translated 91 * @return original character, if it's present on GSM 7-bit alphabet; a 92 * corresponding character, based on the translation table or white 93 * space, if no mapping is found in the translation table for such 94 * character 95 */ translateIfNeeded(char c, boolean isCdmaFormat)96 private static char translateIfNeeded(char c, boolean isCdmaFormat) { 97 if (noTranslationNeeded(c, isCdmaFormat)) { 98 if (DBG) { 99 Rlog.v(TAG, "No translation needed for " + Integer.toHexString(c)); 100 } 101 return c; 102 } 103 104 /* 105 * Trying to translate unicode to Gsm 7-bit alphabet; If c is not 106 * present on translation table, c does not belong to Unicode Latin-1 107 * (Basic + Supplement), so we don't know how to translate it to a Gsm 108 * 7-bit character! We replace c for an empty space and advises the user 109 * about it. 110 */ 111 int translation = -1; 112 113 if (mTranslationTableCommon != null) { 114 translation = mTranslationTableCommon.get(c, -1); 115 } 116 117 if (translation == -1) { 118 if (isCdmaFormat) { 119 if (mTranslationTableCDMA != null) { 120 translation = mTranslationTableCDMA.get(c, -1); 121 } 122 } else { 123 if (mTranslationTableGSM != null) { 124 translation = mTranslationTableGSM.get(c, -1); 125 } 126 } 127 } 128 129 if (translation != -1) { 130 if (DBG) { 131 Rlog.v(TAG, Integer.toHexString(c) + " (" + c + ")" + " translated to " 132 + Integer.toHexString(translation) + " (" + (char) translation + ")"); 133 } 134 return (char) translation; 135 } else { 136 if (DBG) { 137 Rlog.w(TAG, "No translation found for " + Integer.toHexString(c) 138 + "! Replacing for empty space"); 139 } 140 return ' '; 141 } 142 } 143 noTranslationNeeded(char c, boolean isCdmaFormat)144 private static boolean noTranslationNeeded(char c, boolean isCdmaFormat) { 145 if (isCdmaFormat) { 146 return GsmAlphabet.isGsmSeptets(c) && UserData.charToAscii.get(c, -1) != -1; 147 } 148 else { 149 return GsmAlphabet.isGsmSeptets(c); 150 } 151 } 152 153 /** 154 * Load the whole translation table file from the framework resource 155 * encoded in XML. 156 */ load7BitTranslationTableFromXml()157 private static void load7BitTranslationTableFromXml() { 158 XmlResourceParser parser = null; 159 Resources r = Resources.getSystem(); 160 161 if (parser == null) { 162 if (DBG) Rlog.d(TAG, "load7BitTranslationTableFromXml: open normal file"); 163 parser = r.getXml(com.android.internal.R.xml.sms_7bit_translation_table); 164 } 165 166 try { 167 XmlUtils.beginDocument(parser, XML_START_TAG); 168 while (true) { 169 XmlUtils.nextElement(parser); 170 String tag = parser.getName(); 171 if (DBG) { 172 Rlog.d(TAG, "tag: " + tag); 173 } 174 if (XML_TRANSLATION_TYPE_TAG.equals(tag)) { 175 String type = parser.getAttributeValue(null, "Type"); 176 if (DBG) { 177 Rlog.d(TAG, "type: " + type); 178 } 179 if (type.equals("common")) { 180 mTranslationTable = mTranslationTableCommon; 181 } else if (type.equals("gsm")) { 182 mTranslationTable = mTranslationTableGSM; 183 } else if (type.equals("cdma")) { 184 mTranslationTable = mTranslationTableCDMA; 185 } else { 186 Rlog.e(TAG, "Error Parsing 7BitTranslationTable: found incorrect type" + type); 187 } 188 } else if (XML_CHARACTOR_TAG.equals(tag) && mTranslationTable != null) { 189 int from = parser.getAttributeUnsignedIntValue(null, 190 XML_FROM_TAG, -1); 191 int to = parser.getAttributeUnsignedIntValue(null, 192 XML_TO_TAG, -1); 193 if ((from != -1) && (to != -1)) { 194 if (DBG) { 195 Rlog.d(TAG, "Loading mapping " + Integer.toHexString(from) 196 .toUpperCase() + " -> " + Integer.toHexString(to) 197 .toUpperCase()); 198 } 199 mTranslationTable.put (from, to); 200 } else { 201 Rlog.d(TAG, "Invalid translation table file format"); 202 } 203 } else { 204 break; 205 } 206 } 207 if (DBG) Rlog.d(TAG, "load7BitTranslationTableFromXml: parsing successful, file loaded"); 208 } catch (Exception e) { 209 Rlog.e(TAG, "Got exception while loading 7BitTranslationTable file.", e); 210 } finally { 211 if (parser instanceof XmlResourceParser) { 212 ((XmlResourceParser)parser).close(); 213 } 214 } 215 } 216 } 217