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 #include <binder/IBinder.h> 23 24 #include <android-base/result.h> 25 #include <input/Input.h> 26 #include <utils/Errors.h> 27 #include <utils/Tokenizer.h> 28 #include <utils/Unicode.h> 29 #include <map> 30 31 // Maximum number of keys supported by KeyCharacterMaps 32 #define MAX_KEYS 8192 33 34 namespace android { 35 36 /** 37 * Describes a mapping from Android key codes to characters. 38 * Also specifies other functions of the keyboard such as the keyboard type 39 * and key modifier semantics. 40 * 41 * This object is immutable after it has been loaded. 42 */ 43 class KeyCharacterMap { 44 public: 45 enum class KeyboardType : int32_t { 46 UNKNOWN = 0, 47 NUMERIC = 1, 48 PREDICTIVE = 2, 49 ALPHA = 3, 50 FULL = 4, 51 /** 52 * Deprecated. Set 'keyboard.specialFunction' to '1' in the device's IDC file instead. 53 */ 54 SPECIAL_FUNCTION = 5, 55 OVERLAY = 6, 56 }; 57 58 enum class Format { 59 // Base keyboard layout, may contain device-specific options, such as "type" declaration. 60 BASE = 0, 61 // Overlay keyboard layout, more restrictive, may be published by applications, 62 // cannot override device-specific options. 63 OVERLAY = 1, 64 // Either base or overlay layout ok. 65 ANY = 2, 66 }; 67 68 // Substitute key code and meta state for fallback action. 69 struct FallbackAction { 70 int32_t keyCode; 71 int32_t metaState; 72 }; 73 74 /* Loads a key character map from a file. */ 75 static base::Result<std::shared_ptr<KeyCharacterMap>> load(const std::string& filename, 76 Format format); 77 78 /* Loads a key character map from its string contents. */ 79 static base::Result<std::shared_ptr<KeyCharacterMap>> loadContents(const std::string& filename, 80 const char* contents, 81 Format format); 82 83 const std::string getLoadFileName() const; 84 85 /* Combines this key character map with the provided overlay. */ 86 void combine(const KeyCharacterMap& overlay); 87 88 /* Clears already applied layout overlay */ 89 void clearLayoutOverlay(); 90 91 /* Gets the keyboard type. */ 92 KeyboardType getKeyboardType() const; 93 94 /* Gets the primary character for this key as in the label physically printed on it. 95 * Returns 0 if none (eg. for non-printing keys). */ 96 char16_t getDisplayLabel(int32_t keyCode) const; 97 98 /* Gets the Unicode character for the number or symbol generated by the key 99 * when the keyboard is used as a dialing pad. 100 * Returns 0 if no number or symbol is generated. 101 */ 102 char16_t getNumber(int32_t keyCode) const; 103 104 /* Gets the Unicode character generated by the key and meta key modifiers. 105 * Returns 0 if no character is generated. 106 */ 107 char16_t getCharacter(int32_t keyCode, int32_t metaState) const; 108 109 /* Gets the fallback action to use by default if the application does not 110 * handle the specified key. 111 * Returns true if an action was available, false if none. 112 */ 113 bool getFallbackAction(int32_t keyCode, int32_t metaState, 114 FallbackAction* outFallbackAction) const; 115 116 /* Gets the first matching Unicode character that can be generated by the key, 117 * preferring the one with the specified meta key modifiers. 118 * Returns 0 if no matching character is generated. 119 */ 120 char16_t getMatch(int32_t keyCode, const char16_t* chars, 121 size_t numChars, int32_t metaState) const; 122 123 /* Gets a sequence of key events that could plausibly generate the specified 124 * character sequence. Returns false if some of the characters cannot be generated. 125 */ 126 bool getEvents(int32_t deviceId, const char16_t* chars, size_t numChars, 127 Vector<KeyEvent>& outEvents) const; 128 129 /* Maps an Android key code to another Android key code. This mapping is applied after scanCode 130 * and usageCodes are mapped to corresponding Android Keycode */ 131 void addKeyRemapping(int32_t fromKeyCode, int32_t toKeyCode); 132 133 /* Maps a scan code and usage code to a key code, in case this key map overrides 134 * the mapping in some way. */ 135 status_t mapKey(int32_t scanCode, int32_t usageCode, int32_t* outKeyCode) const; 136 137 /* Returns keycode after applying Android key code remapping defined in mKeyRemapping */ 138 int32_t applyKeyRemapping(int32_t fromKeyCode) const; 139 140 /* Returns the <keyCode, metaState> pair after applying key behavior defined in the kcm file, 141 * that tries to find a replacement key code based on current meta state */ 142 std::pair<int32_t /*keyCode*/, int32_t /*metaState*/> applyKeyBehavior(int32_t keyCode, 143 int32_t metaState) const; 144 145 /* Reads a key map from a parcel. */ 146 static std::unique_ptr<KeyCharacterMap> readFromParcel(Parcel* parcel); 147 148 /* Writes a key map to a parcel. */ 149 void writeToParcel(Parcel* parcel) const; 150 151 bool operator==(const KeyCharacterMap& other) const = default; 152 153 KeyCharacterMap(const KeyCharacterMap& other) = default; 154 155 private: 156 struct Behavior { 157 /* The meta key modifiers for this behavior. */ 158 int32_t metaState = 0; 159 160 /* The character to insert. */ 161 char16_t character = 0; 162 163 /* The fallback keycode if the key is not handled. */ 164 int32_t fallbackKeyCode = 0; 165 166 /* The replacement keycode if the key has to be replaced outright. */ 167 int32_t replacementKeyCode = 0; 168 169 bool operator==(const Behavior&) const = default; 170 }; 171 172 struct Key { 173 bool operator==(const Key&) const = default; 174 175 /* The single character label printed on the key, or 0 if none. */ 176 char16_t label = 0; 177 178 /* The number or symbol character generated by the key, or 0 if none. */ 179 char16_t number = 0; 180 181 /* The list of key behaviors sorted from most specific to least specific 182 * meta key binding. */ 183 std::list<Behavior> behaviors; 184 }; 185 186 class Parser { 187 enum State { 188 STATE_TOP = 0, 189 STATE_KEY = 1, 190 }; 191 192 enum { 193 PROPERTY_LABEL = 1, 194 PROPERTY_NUMBER = 2, 195 PROPERTY_META = 3, 196 }; 197 198 struct Property { 199 inline explicit Property(int32_t property = 0, int32_t metaState = 0) : propertyProperty200 property(property), metaState(metaState) { } 201 202 int32_t property; 203 int32_t metaState; 204 }; 205 206 KeyCharacterMap* mMap; 207 Tokenizer* mTokenizer; 208 Format mFormat; 209 State mState; 210 int32_t mKeyCode; 211 212 public: 213 Parser(KeyCharacterMap* map, Tokenizer* tokenizer, Format format); 214 status_t parse(); 215 216 private: 217 status_t parseType(); 218 status_t parseMap(); 219 status_t parseMapKey(); 220 status_t parseKey(); 221 status_t parseKeyProperty(); 222 status_t finishKey(Key& key); 223 status_t parseModifier(const std::string& token, int32_t* outMetaState); 224 status_t parseCharacterLiteral(char16_t* outCharacter); 225 }; 226 227 std::map<int32_t, Key> mKeys; 228 KeyboardType mType = KeyboardType::UNKNOWN; 229 std::string mLoadFileName; 230 bool mLayoutOverlayApplied = false; 231 232 std::map<int32_t /* fromAndroidKeyCode */, int32_t /* toAndroidKeyCode */> mKeyRemapping; 233 std::map<int32_t /* fromScanCode */, int32_t /* toAndroidKeyCode */> mKeysByScanCode; 234 std::map<int32_t /* fromHidUsageCode */, int32_t /* toAndroidKeyCode */> mKeysByUsageCode; 235 236 KeyCharacterMap(const std::string& filename); 237 238 const Key* getKey(int32_t keyCode) const; 239 const Behavior* getKeyBehavior(int32_t keyCode, int32_t metaState) const; 240 static bool matchesMetaState(int32_t eventMetaState, int32_t behaviorMetaState); 241 242 bool findKey(char16_t ch, int32_t* outKeyCode, int32_t* outMetaState) const; 243 244 static void addKey(Vector<KeyEvent>& outEvents, 245 int32_t deviceId, int32_t keyCode, int32_t metaState, bool down, nsecs_t time); 246 static void addMetaKeys(Vector<KeyEvent>& outEvents, 247 int32_t deviceId, int32_t metaState, bool down, nsecs_t time, 248 int32_t* currentMetaState); 249 static bool addSingleEphemeralMetaKey(Vector<KeyEvent>& outEvents, 250 int32_t deviceId, int32_t metaState, bool down, nsecs_t time, 251 int32_t keyCode, int32_t keyMetaState, 252 int32_t* currentMetaState); 253 static void addDoubleEphemeralMetaKey(Vector<KeyEvent>& outEvents, 254 int32_t deviceId, int32_t metaState, bool down, nsecs_t time, 255 int32_t leftKeyCode, int32_t leftKeyMetaState, 256 int32_t rightKeyCode, int32_t rightKeyMetaState, 257 int32_t eitherKeyMetaState, 258 int32_t* currentMetaState); 259 static void addLockedMetaKey(Vector<KeyEvent>& outEvents, 260 int32_t deviceId, int32_t metaState, nsecs_t time, 261 int32_t keyCode, int32_t keyMetaState, 262 int32_t* currentMetaState); 263 264 /* Clears all data stored in this key character map */ 265 void clear(); 266 267 /* Loads the KeyCharacterMap provided by the tokenizer into this instance. */ 268 status_t load(Tokenizer* tokenizer, Format format); 269 270 /* Reloads the data from mLoadFileName and unapplies any overlay. */ 271 status_t reloadBaseFromFile(); 272 }; 273 274 } // namespace android 275