1 /* 2 * Copyright (C) 2008 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 #pragma once 18 19 #include <stdint.h> 20 #include <list> 21 22 #ifdef __linux__ 23 #include <binder/IBinder.h> 24 #endif 25 26 #include <android-base/result.h> 27 #include <input/Input.h> 28 #include <utils/Errors.h> 29 #include <utils/Tokenizer.h> 30 #include <utils/Unicode.h> 31 #include <map> 32 33 // Maximum number of keys supported by KeyCharacterMaps 34 #define MAX_KEYS 8192 35 36 namespace android { 37 38 /** 39 * Describes a mapping from Android key codes to characters. 40 * Also specifies other functions of the keyboard such as the keyboard type 41 * and key modifier semantics. 42 * 43 * This object is immutable after it has been loaded. 44 */ 45 class KeyCharacterMap { 46 public: 47 enum class KeyboardType : int32_t { 48 UNKNOWN = 0, 49 NUMERIC = 1, 50 PREDICTIVE = 2, 51 ALPHA = 3, 52 FULL = 4, 53 /** 54 * Deprecated. Set 'keyboard.specialFunction' to '1' in the device's IDC file instead. 55 */ 56 SPECIAL_FUNCTION = 5, 57 OVERLAY = 6, 58 }; 59 60 enum class Format { 61 // Base keyboard layout, may contain device-specific options, such as "type" declaration. 62 BASE = 0, 63 // Overlay keyboard layout, more restrictive, may be published by applications, 64 // cannot override device-specific options. 65 OVERLAY = 1, 66 // Either base or overlay layout ok. 67 ANY = 2, 68 }; 69 70 // Substitute key code and meta state for fallback action. 71 struct FallbackAction { 72 int32_t keyCode; 73 int32_t metaState; 74 }; 75 76 /* Loads a key character map from a file. */ 77 static base::Result<std::shared_ptr<KeyCharacterMap>> load(const std::string& filename, 78 Format format); 79 80 /* Loads a key character map from its string contents. */ 81 static base::Result<std::shared_ptr<KeyCharacterMap>> loadContents(const std::string& filename, 82 const char* contents, 83 Format format); 84 85 const std::string getLoadFileName() const; 86 87 /* Combines this key character map with the provided overlay. */ 88 void combine(const KeyCharacterMap& overlay); 89 90 /* Clears already applied layout overlay */ 91 void clearLayoutOverlay(); 92 93 /* Gets the keyboard type. */ 94 KeyboardType getKeyboardType() const; 95 96 /* Gets the primary character for this key as in the label physically printed on it. 97 * Returns 0 if none (eg. for non-printing keys). */ 98 char16_t getDisplayLabel(int32_t keyCode) const; 99 100 /* Gets the Unicode character for the number or symbol generated by the key 101 * when the keyboard is used as a dialing pad. 102 * Returns 0 if no number or symbol is generated. 103 */ 104 char16_t getNumber(int32_t keyCode) const; 105 106 /* Gets the Unicode character generated by the key and meta key modifiers. 107 * Returns 0 if no character is generated. 108 */ 109 char16_t getCharacter(int32_t keyCode, int32_t metaState) const; 110 111 /* Gets the fallback action to use by default if the application does not 112 * handle the specified key. 113 * Returns true if an action was available, false if none. 114 */ 115 bool getFallbackAction(int32_t keyCode, int32_t metaState, 116 FallbackAction* outFallbackAction) const; 117 118 /* Gets the first matching Unicode character that can be generated by the key, 119 * preferring the one with the specified meta key modifiers. 120 * Returns 0 if no matching character is generated. 121 */ 122 char16_t getMatch(int32_t keyCode, const char16_t* chars, 123 size_t numChars, int32_t metaState) const; 124 125 /* Gets a sequence of key events that could plausibly generate the specified 126 * character sequence. Returns false if some of the characters cannot be generated. 127 */ 128 bool getEvents(int32_t deviceId, const char16_t* chars, size_t numChars, 129 Vector<KeyEvent>& outEvents) const; 130 131 /* Maps an Android key code to another Android key code. This mapping is applied after scanCode 132 * and usageCodes are mapped to corresponding Android Keycode */ 133 void addKeyRemapping(int32_t fromKeyCode, int32_t toKeyCode); 134 135 /* Maps a scan code and usage code to a key code, in case this key map overrides 136 * the mapping in some way. */ 137 status_t mapKey(int32_t scanCode, int32_t usageCode, int32_t* outKeyCode) const; 138 139 /* Returns keycode after applying Android key code remapping defined in mKeyRemapping */ 140 int32_t applyKeyRemapping(int32_t fromKeyCode) const; 141 142 /* Returns the <keyCode, metaState> pair after applying key behavior defined in the kcm file, 143 * that tries to find a replacement key code based on current meta state */ 144 std::pair<int32_t /*keyCode*/, int32_t /*metaState*/> applyKeyBehavior(int32_t keyCode, 145 int32_t metaState) const; 146 147 #ifdef __linux__ 148 /* Reads a key map from a parcel. */ 149 static std::shared_ptr<KeyCharacterMap> readFromParcel(Parcel* parcel); 150 151 /* Writes a key map to a parcel. */ 152 void writeToParcel(Parcel* parcel) const; 153 #endif 154 155 bool operator==(const KeyCharacterMap& other) const = default; 156 157 KeyCharacterMap(const KeyCharacterMap& other) = default; 158 159 private: 160 struct Behavior { 161 /* The meta key modifiers for this behavior. */ 162 int32_t metaState = 0; 163 164 /* The character to insert. */ 165 char16_t character = 0; 166 167 /* The fallback keycode if the key is not handled. */ 168 int32_t fallbackKeyCode = 0; 169 170 /* The replacement keycode if the key has to be replaced outright. */ 171 int32_t replacementKeyCode = 0; 172 173 bool operator==(const Behavior&) const = default; 174 }; 175 176 struct Key { 177 bool operator==(const Key&) const = default; 178 179 /* The single character label printed on the key, or 0 if none. */ 180 char16_t label = 0; 181 182 /* The number or symbol character generated by the key, or 0 if none. */ 183 char16_t number = 0; 184 185 /* The list of key behaviors sorted from most specific to least specific 186 * meta key binding. */ 187 std::list<Behavior> behaviors; 188 }; 189 190 class Parser { 191 enum State { 192 STATE_TOP = 0, 193 STATE_KEY = 1, 194 }; 195 196 enum { 197 PROPERTY_LABEL = 1, 198 PROPERTY_NUMBER = 2, 199 PROPERTY_META = 3, 200 }; 201 202 struct Property { 203 inline explicit Property(int32_t property = 0, int32_t metaState = 0) : propertyProperty204 property(property), metaState(metaState) { } 205 206 int32_t property; 207 int32_t metaState; 208 }; 209 210 KeyCharacterMap* mMap; 211 Tokenizer* mTokenizer; 212 Format mFormat; 213 State mState; 214 int32_t mKeyCode; 215 216 public: 217 Parser(KeyCharacterMap* map, Tokenizer* tokenizer, Format format); 218 status_t parse(); 219 220 private: 221 status_t parseType(); 222 status_t parseMap(); 223 status_t parseMapKey(); 224 status_t parseKey(); 225 status_t parseKeyProperty(); 226 status_t finishKey(Key& key); 227 status_t parseModifier(const std::string& token, int32_t* outMetaState); 228 status_t parseCharacterLiteral(char16_t* outCharacter); 229 }; 230 231 std::map<int32_t, Key> mKeys; 232 KeyboardType mType = KeyboardType::UNKNOWN; 233 std::string mLoadFileName; 234 bool mLayoutOverlayApplied = false; 235 236 std::map<int32_t /* fromAndroidKeyCode */, int32_t /* toAndroidKeyCode */> mKeyRemapping; 237 std::map<int32_t /* fromScanCode */, int32_t /* toAndroidKeyCode */> mKeysByScanCode; 238 std::map<int32_t /* fromHidUsageCode */, int32_t /* toAndroidKeyCode */> mKeysByUsageCode; 239 240 KeyCharacterMap(const std::string& filename); 241 242 const Key* getKey(int32_t keyCode) const; 243 const Behavior* getKeyBehavior(int32_t keyCode, int32_t metaState) const; 244 static bool matchesMetaState(int32_t eventMetaState, int32_t behaviorMetaState); 245 246 bool findKey(char16_t ch, int32_t* outKeyCode, int32_t* outMetaState) const; 247 248 static void addKey(Vector<KeyEvent>& outEvents, 249 int32_t deviceId, int32_t keyCode, int32_t metaState, bool down, nsecs_t time); 250 static void addMetaKeys(Vector<KeyEvent>& outEvents, 251 int32_t deviceId, int32_t metaState, bool down, nsecs_t time, 252 int32_t* currentMetaState); 253 static bool addSingleEphemeralMetaKey(Vector<KeyEvent>& outEvents, 254 int32_t deviceId, int32_t metaState, bool down, nsecs_t time, 255 int32_t keyCode, int32_t keyMetaState, 256 int32_t* currentMetaState); 257 static void addDoubleEphemeralMetaKey(Vector<KeyEvent>& outEvents, 258 int32_t deviceId, int32_t metaState, bool down, nsecs_t time, 259 int32_t leftKeyCode, int32_t leftKeyMetaState, 260 int32_t rightKeyCode, int32_t rightKeyMetaState, 261 int32_t eitherKeyMetaState, 262 int32_t* currentMetaState); 263 static void addLockedMetaKey(Vector<KeyEvent>& outEvents, 264 int32_t deviceId, int32_t metaState, nsecs_t time, 265 int32_t keyCode, int32_t keyMetaState, 266 int32_t* currentMetaState); 267 268 /* Clears all data stored in this key character map */ 269 void clear(); 270 271 /* Loads the KeyCharacterMap provided by the tokenizer into this instance. */ 272 status_t load(Tokenizer* tokenizer, Format format); 273 274 /* Reloads the data from mLoadFileName and unapplies any overlay. */ 275 status_t reloadBaseFromFile(); 276 }; 277 278 } // namespace android 279