1 /*
2  * Copyright 2023 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 #define LOG_TAG "VirtualInputDevice"
18 
19 #include <android/input.h>
20 #include <android/keycodes.h>
21 #include <fcntl.h>
22 #include <input/Input.h>
23 #include <input/VirtualInputDevice.h>
24 #include <linux/uinput.h>
25 #include <math.h>
26 #include <utils/Log.h>
27 
28 #include <map>
29 #include <string>
30 
31 using android::base::unique_fd;
32 
33 /**
34  * Log debug messages about native virtual input devices.
35  * Enable this via "adb shell setprop log.tag.VirtualInputDevice DEBUG"
36  */
isDebug()37 static bool isDebug() {
38     return __android_log_is_loggable(ANDROID_LOG_DEBUG, LOG_TAG, ANDROID_LOG_INFO);
39 }
40 
41 namespace android {
42 
VirtualInputDevice(unique_fd fd)43 VirtualInputDevice::VirtualInputDevice(unique_fd fd) : mFd(std::move(fd)) {}
44 
~VirtualInputDevice()45 VirtualInputDevice::~VirtualInputDevice() {
46     ioctl(mFd, UI_DEV_DESTROY);
47 }
48 
writeInputEvent(uint16_t type,uint16_t code,int32_t value,std::chrono::nanoseconds eventTime)49 bool VirtualInputDevice::writeInputEvent(uint16_t type, uint16_t code, int32_t value,
50                                          std::chrono::nanoseconds eventTime) {
51     std::chrono::seconds seconds = std::chrono::duration_cast<std::chrono::seconds>(eventTime);
52     std::chrono::microseconds microseconds =
53             std::chrono::duration_cast<std::chrono::microseconds>(eventTime - seconds);
54     struct input_event ev = {.type = type, .code = code, .value = value};
55     ev.input_event_sec = static_cast<decltype(ev.input_event_sec)>(seconds.count());
56     ev.input_event_usec = static_cast<decltype(ev.input_event_usec)>(microseconds.count());
57 
58     return TEMP_FAILURE_RETRY(write(mFd, &ev, sizeof(struct input_event))) == sizeof(ev);
59 }
60 
61 /** Utility method to write keyboard key events or mouse/stylus button events. */
writeEvKeyEvent(int32_t androidCode,int32_t androidAction,const std::map<int,int> & evKeyCodeMapping,const std::map<int,UinputAction> & actionMapping,std::chrono::nanoseconds eventTime)62 bool VirtualInputDevice::writeEvKeyEvent(int32_t androidCode, int32_t androidAction,
63                                          const std::map<int, int>& evKeyCodeMapping,
64                                          const std::map<int, UinputAction>& actionMapping,
65                                          std::chrono::nanoseconds eventTime) {
66     auto evKeyCodeIterator = evKeyCodeMapping.find(androidCode);
67     if (evKeyCodeIterator == evKeyCodeMapping.end()) {
68         ALOGE("Unsupported native EV keycode for android code %d", androidCode);
69         return false;
70     }
71     auto actionIterator = actionMapping.find(androidAction);
72     if (actionIterator == actionMapping.end()) {
73         ALOGE("Unsupported native action for android action %d", androidAction);
74         return false;
75     }
76     int32_t action = static_cast<int32_t>(actionIterator->second);
77     uint16_t evKeyCode = static_cast<uint16_t>(evKeyCodeIterator->second);
78     if (!writeInputEvent(EV_KEY, evKeyCode, action, eventTime)) {
79         ALOGE("Failed to write native action %d and EV keycode %u.", action, evKeyCode);
80         return false;
81     }
82     if (!writeInputEvent(EV_SYN, SYN_REPORT, 0, eventTime)) {
83         ALOGE("Failed to write SYN_REPORT for EV_KEY event.");
84         return false;
85     }
86     return true;
87 }
88 
89 // --- VirtualKeyboard ---
90 const std::map<int, UinputAction> VirtualKeyboard::KEY_ACTION_MAPPING = {
91         {AKEY_EVENT_ACTION_DOWN, UinputAction::PRESS},
92         {AKEY_EVENT_ACTION_UP, UinputAction::RELEASE},
93 };
94 
95 // Keycode mapping from https://source.android.com/devices/input/keyboard-devices
96 const std::map<int, int> VirtualKeyboard::KEY_CODE_MAPPING = {
97         {AKEYCODE_0, KEY_0},
98         {AKEYCODE_1, KEY_1},
99         {AKEYCODE_2, KEY_2},
100         {AKEYCODE_3, KEY_3},
101         {AKEYCODE_4, KEY_4},
102         {AKEYCODE_5, KEY_5},
103         {AKEYCODE_6, KEY_6},
104         {AKEYCODE_7, KEY_7},
105         {AKEYCODE_8, KEY_8},
106         {AKEYCODE_9, KEY_9},
107         {AKEYCODE_A, KEY_A},
108         {AKEYCODE_B, KEY_B},
109         {AKEYCODE_C, KEY_C},
110         {AKEYCODE_D, KEY_D},
111         {AKEYCODE_E, KEY_E},
112         {AKEYCODE_F, KEY_F},
113         {AKEYCODE_G, KEY_G},
114         {AKEYCODE_H, KEY_H},
115         {AKEYCODE_I, KEY_I},
116         {AKEYCODE_J, KEY_J},
117         {AKEYCODE_K, KEY_K},
118         {AKEYCODE_L, KEY_L},
119         {AKEYCODE_M, KEY_M},
120         {AKEYCODE_N, KEY_N},
121         {AKEYCODE_O, KEY_O},
122         {AKEYCODE_P, KEY_P},
123         {AKEYCODE_Q, KEY_Q},
124         {AKEYCODE_R, KEY_R},
125         {AKEYCODE_S, KEY_S},
126         {AKEYCODE_T, KEY_T},
127         {AKEYCODE_U, KEY_U},
128         {AKEYCODE_V, KEY_V},
129         {AKEYCODE_W, KEY_W},
130         {AKEYCODE_X, KEY_X},
131         {AKEYCODE_Y, KEY_Y},
132         {AKEYCODE_Z, KEY_Z},
133         {AKEYCODE_GRAVE, KEY_GRAVE},
134         {AKEYCODE_MINUS, KEY_MINUS},
135         {AKEYCODE_EQUALS, KEY_EQUAL},
136         {AKEYCODE_LEFT_BRACKET, KEY_LEFTBRACE},
137         {AKEYCODE_RIGHT_BRACKET, KEY_RIGHTBRACE},
138         {AKEYCODE_BACKSLASH, KEY_BACKSLASH},
139         {AKEYCODE_SEMICOLON, KEY_SEMICOLON},
140         {AKEYCODE_APOSTROPHE, KEY_APOSTROPHE},
141         {AKEYCODE_COMMA, KEY_COMMA},
142         {AKEYCODE_PERIOD, KEY_DOT},
143         {AKEYCODE_SLASH, KEY_SLASH},
144         {AKEYCODE_ALT_LEFT, KEY_LEFTALT},
145         {AKEYCODE_ALT_RIGHT, KEY_RIGHTALT},
146         {AKEYCODE_CTRL_LEFT, KEY_LEFTCTRL},
147         {AKEYCODE_CTRL_RIGHT, KEY_RIGHTCTRL},
148         {AKEYCODE_SHIFT_LEFT, KEY_LEFTSHIFT},
149         {AKEYCODE_SHIFT_RIGHT, KEY_RIGHTSHIFT},
150         {AKEYCODE_META_LEFT, KEY_LEFTMETA},
151         {AKEYCODE_META_RIGHT, KEY_RIGHTMETA},
152         {AKEYCODE_CAPS_LOCK, KEY_CAPSLOCK},
153         {AKEYCODE_SCROLL_LOCK, KEY_SCROLLLOCK},
154         {AKEYCODE_NUM_LOCK, KEY_NUMLOCK},
155         {AKEYCODE_ENTER, KEY_ENTER},
156         {AKEYCODE_TAB, KEY_TAB},
157         {AKEYCODE_SPACE, KEY_SPACE},
158         {AKEYCODE_DPAD_DOWN, KEY_DOWN},
159         {AKEYCODE_DPAD_UP, KEY_UP},
160         {AKEYCODE_DPAD_LEFT, KEY_LEFT},
161         {AKEYCODE_DPAD_RIGHT, KEY_RIGHT},
162         {AKEYCODE_MOVE_END, KEY_END},
163         {AKEYCODE_MOVE_HOME, KEY_HOME},
164         {AKEYCODE_PAGE_DOWN, KEY_PAGEDOWN},
165         {AKEYCODE_PAGE_UP, KEY_PAGEUP},
166         {AKEYCODE_DEL, KEY_BACKSPACE},
167         {AKEYCODE_FORWARD_DEL, KEY_DELETE},
168         {AKEYCODE_INSERT, KEY_INSERT},
169         {AKEYCODE_ESCAPE, KEY_ESC},
170         {AKEYCODE_BREAK, KEY_PAUSE},
171         {AKEYCODE_F1, KEY_F1},
172         {AKEYCODE_F2, KEY_F2},
173         {AKEYCODE_F3, KEY_F3},
174         {AKEYCODE_F4, KEY_F4},
175         {AKEYCODE_F5, KEY_F5},
176         {AKEYCODE_F6, KEY_F6},
177         {AKEYCODE_F7, KEY_F7},
178         {AKEYCODE_F8, KEY_F8},
179         {AKEYCODE_F9, KEY_F9},
180         {AKEYCODE_F10, KEY_F10},
181         {AKEYCODE_F11, KEY_F11},
182         {AKEYCODE_F12, KEY_F12},
183         {AKEYCODE_BACK, KEY_BACK},
184         {AKEYCODE_FORWARD, KEY_FORWARD},
185         {AKEYCODE_NUMPAD_1, KEY_KP1},
186         {AKEYCODE_NUMPAD_2, KEY_KP2},
187         {AKEYCODE_NUMPAD_3, KEY_KP3},
188         {AKEYCODE_NUMPAD_4, KEY_KP4},
189         {AKEYCODE_NUMPAD_5, KEY_KP5},
190         {AKEYCODE_NUMPAD_6, KEY_KP6},
191         {AKEYCODE_NUMPAD_7, KEY_KP7},
192         {AKEYCODE_NUMPAD_8, KEY_KP8},
193         {AKEYCODE_NUMPAD_9, KEY_KP9},
194         {AKEYCODE_NUMPAD_0, KEY_KP0},
195         {AKEYCODE_NUMPAD_ADD, KEY_KPPLUS},
196         {AKEYCODE_NUMPAD_SUBTRACT, KEY_KPMINUS},
197         {AKEYCODE_NUMPAD_MULTIPLY, KEY_KPASTERISK},
198         {AKEYCODE_NUMPAD_DIVIDE, KEY_KPSLASH},
199         {AKEYCODE_NUMPAD_DOT, KEY_KPDOT},
200         {AKEYCODE_NUMPAD_ENTER, KEY_KPENTER},
201         {AKEYCODE_NUMPAD_EQUALS, KEY_KPEQUAL},
202         {AKEYCODE_NUMPAD_COMMA, KEY_KPCOMMA},
203         {AKEYCODE_LANGUAGE_SWITCH, KEY_LANGUAGE},
204 };
205 
VirtualKeyboard(unique_fd fd)206 VirtualKeyboard::VirtualKeyboard(unique_fd fd) : VirtualInputDevice(std::move(fd)) {}
207 
~VirtualKeyboard()208 VirtualKeyboard::~VirtualKeyboard() {}
209 
writeKeyEvent(int32_t androidKeyCode,int32_t androidAction,std::chrono::nanoseconds eventTime)210 bool VirtualKeyboard::writeKeyEvent(int32_t androidKeyCode, int32_t androidAction,
211                                     std::chrono::nanoseconds eventTime) {
212     return writeEvKeyEvent(androidKeyCode, androidAction, KEY_CODE_MAPPING, KEY_ACTION_MAPPING,
213                            eventTime);
214 }
215 
216 // --- VirtualDpad ---
217 // Dpad keycode mapping from https://source.android.com/devices/input/keyboard-devices
218 const std::map<int, int> VirtualDpad::DPAD_KEY_CODE_MAPPING = {
219         // clang-format off
220         {AKEYCODE_DPAD_DOWN, KEY_DOWN},
221         {AKEYCODE_DPAD_UP, KEY_UP},
222         {AKEYCODE_DPAD_LEFT, KEY_LEFT},
223         {AKEYCODE_DPAD_RIGHT, KEY_RIGHT},
224         {AKEYCODE_DPAD_CENTER, KEY_SELECT},
225         {AKEYCODE_BACK, KEY_BACK},
226         // clang-format on
227 };
228 
VirtualDpad(unique_fd fd)229 VirtualDpad::VirtualDpad(unique_fd fd) : VirtualInputDevice(std::move(fd)) {}
230 
~VirtualDpad()231 VirtualDpad::~VirtualDpad() {}
232 
writeDpadKeyEvent(int32_t androidKeyCode,int32_t androidAction,std::chrono::nanoseconds eventTime)233 bool VirtualDpad::writeDpadKeyEvent(int32_t androidKeyCode, int32_t androidAction,
234                                     std::chrono::nanoseconds eventTime) {
235     return writeEvKeyEvent(androidKeyCode, androidAction, DPAD_KEY_CODE_MAPPING,
236                            VirtualKeyboard::KEY_ACTION_MAPPING, eventTime);
237 }
238 
239 // --- VirtualMouse ---
240 const std::map<int, UinputAction> VirtualMouse::BUTTON_ACTION_MAPPING = {
241         {AMOTION_EVENT_ACTION_BUTTON_PRESS, UinputAction::PRESS},
242         {AMOTION_EVENT_ACTION_BUTTON_RELEASE, UinputAction::RELEASE},
243 };
244 
245 // Button code mapping from https://source.android.com/devices/input/touch-devices
246 const std::map<int, int> VirtualMouse::BUTTON_CODE_MAPPING = {
247         // clang-format off
248         {AMOTION_EVENT_BUTTON_PRIMARY, BTN_LEFT},
249         {AMOTION_EVENT_BUTTON_SECONDARY, BTN_RIGHT},
250         {AMOTION_EVENT_BUTTON_TERTIARY, BTN_MIDDLE},
251         {AMOTION_EVENT_BUTTON_BACK, BTN_BACK},
252         {AMOTION_EVENT_BUTTON_FORWARD, BTN_FORWARD},
253         // clang-format on
254 };
255 
VirtualMouse(unique_fd fd)256 VirtualMouse::VirtualMouse(unique_fd fd) : VirtualInputDevice(std::move(fd)) {}
257 
~VirtualMouse()258 VirtualMouse::~VirtualMouse() {}
259 
writeButtonEvent(int32_t androidButtonCode,int32_t androidAction,std::chrono::nanoseconds eventTime)260 bool VirtualMouse::writeButtonEvent(int32_t androidButtonCode, int32_t androidAction,
261                                     std::chrono::nanoseconds eventTime) {
262     return writeEvKeyEvent(androidButtonCode, androidAction, BUTTON_CODE_MAPPING,
263                            BUTTON_ACTION_MAPPING, eventTime);
264 }
265 
writeRelativeEvent(float relativeX,float relativeY,std::chrono::nanoseconds eventTime)266 bool VirtualMouse::writeRelativeEvent(float relativeX, float relativeY,
267                                       std::chrono::nanoseconds eventTime) {
268     return writeInputEvent(EV_REL, REL_X, relativeX, eventTime) &&
269             writeInputEvent(EV_REL, REL_Y, relativeY, eventTime) &&
270             writeInputEvent(EV_SYN, SYN_REPORT, 0, eventTime);
271 }
272 
writeScrollEvent(float xAxisMovement,float yAxisMovement,std::chrono::nanoseconds eventTime)273 bool VirtualMouse::writeScrollEvent(float xAxisMovement, float yAxisMovement,
274                                     std::chrono::nanoseconds eventTime) {
275     return writeInputEvent(EV_REL, REL_HWHEEL, xAxisMovement, eventTime) &&
276             writeInputEvent(EV_REL, REL_WHEEL, yAxisMovement, eventTime) &&
277             writeInputEvent(EV_SYN, SYN_REPORT, 0, eventTime);
278 }
279 
280 // --- VirtualTouchscreen ---
281 const std::map<int, UinputAction> VirtualTouchscreen::TOUCH_ACTION_MAPPING = {
282         {AMOTION_EVENT_ACTION_DOWN, UinputAction::PRESS},
283         {AMOTION_EVENT_ACTION_UP, UinputAction::RELEASE},
284         {AMOTION_EVENT_ACTION_MOVE, UinputAction::MOVE},
285         {AMOTION_EVENT_ACTION_CANCEL, UinputAction::CANCEL},
286 };
287 
288 // Tool type mapping from https://source.android.com/devices/input/touch-devices
289 const std::map<int, int> VirtualTouchscreen::TOOL_TYPE_MAPPING = {
290         {AMOTION_EVENT_TOOL_TYPE_FINGER, MT_TOOL_FINGER},
291         {AMOTION_EVENT_TOOL_TYPE_PALM, MT_TOOL_PALM},
292 };
293 
VirtualTouchscreen(unique_fd fd)294 VirtualTouchscreen::VirtualTouchscreen(unique_fd fd) : VirtualInputDevice(std::move(fd)) {}
295 
~VirtualTouchscreen()296 VirtualTouchscreen::~VirtualTouchscreen() {}
297 
isValidPointerId(int32_t pointerId,UinputAction uinputAction)298 bool VirtualTouchscreen::isValidPointerId(int32_t pointerId, UinputAction uinputAction) {
299     if (pointerId < -1 || pointerId >= (int)MAX_POINTERS) {
300         ALOGE("Virtual touch event has invalid pointer id %d; value must be between -1 and %zu",
301               pointerId, MAX_POINTERS - 0);
302         return false;
303     }
304 
305     if (uinputAction == UinputAction::PRESS && mActivePointers.test(pointerId)) {
306         ALOGE("Repetitive action DOWN event received on a pointer %d that is already down.",
307               pointerId);
308         return false;
309     }
310     if (uinputAction == UinputAction::RELEASE && !mActivePointers.test(pointerId)) {
311         ALOGE("PointerId %d action UP received with no prior action DOWN on touchscreen %d.",
312               pointerId, mFd.get());
313         return false;
314     }
315     return true;
316 }
317 
writeTouchEvent(int32_t pointerId,int32_t toolType,int32_t action,float locationX,float locationY,float pressure,float majorAxisSize,std::chrono::nanoseconds eventTime)318 bool VirtualTouchscreen::writeTouchEvent(int32_t pointerId, int32_t toolType, int32_t action,
319                                          float locationX, float locationY, float pressure,
320                                          float majorAxisSize, std::chrono::nanoseconds eventTime) {
321     auto actionIterator = TOUCH_ACTION_MAPPING.find(action);
322     if (actionIterator == TOUCH_ACTION_MAPPING.end()) {
323         return false;
324     }
325     UinputAction uinputAction = actionIterator->second;
326     if (!isValidPointerId(pointerId, uinputAction)) {
327         return false;
328     }
329     if (!writeInputEvent(EV_ABS, ABS_MT_SLOT, pointerId, eventTime)) {
330         return false;
331     }
332     auto toolTypeIterator = TOOL_TYPE_MAPPING.find(toolType);
333     if (toolTypeIterator == TOOL_TYPE_MAPPING.end()) {
334         return false;
335     }
336     if (!writeInputEvent(EV_ABS, ABS_MT_TOOL_TYPE, static_cast<int32_t>(toolTypeIterator->second),
337                          eventTime)) {
338         return false;
339     }
340     if (uinputAction == UinputAction::PRESS && !handleTouchDown(pointerId, eventTime)) {
341         return false;
342     }
343     if (uinputAction == UinputAction::RELEASE && !handleTouchUp(pointerId, eventTime)) {
344         return false;
345     }
346     if (!writeInputEvent(EV_ABS, ABS_MT_POSITION_X, locationX, eventTime)) {
347         return false;
348     }
349     if (!writeInputEvent(EV_ABS, ABS_MT_POSITION_Y, locationY, eventTime)) {
350         return false;
351     }
352     if (!isnan(pressure)) {
353         if (!writeInputEvent(EV_ABS, ABS_MT_PRESSURE, pressure, eventTime)) {
354             return false;
355         }
356     }
357     if (!isnan(majorAxisSize)) {
358         if (!writeInputEvent(EV_ABS, ABS_MT_TOUCH_MAJOR, majorAxisSize, eventTime)) {
359             return false;
360         }
361     }
362     return writeInputEvent(EV_SYN, SYN_REPORT, 0, eventTime);
363 }
364 
handleTouchUp(int32_t pointerId,std::chrono::nanoseconds eventTime)365 bool VirtualTouchscreen::handleTouchUp(int32_t pointerId, std::chrono::nanoseconds eventTime) {
366     if (!writeInputEvent(EV_ABS, ABS_MT_TRACKING_ID, static_cast<int32_t>(-1), eventTime)) {
367         return false;
368     }
369     // When a pointer is no longer in touch, remove the pointer id from the corresponding
370     // entry in the unreleased touches map.
371     mActivePointers.reset(pointerId);
372     ALOGD_IF(isDebug(), "Pointer %d erased from the touchscreen %d", pointerId, mFd.get());
373 
374     // Only sends the BTN UP event when there's no pointers on the touchscreen.
375     if (mActivePointers.none()) {
376         if (!writeInputEvent(EV_KEY, BTN_TOUCH, static_cast<int32_t>(UinputAction::RELEASE),
377                              eventTime)) {
378             return false;
379         }
380         ALOGD_IF(isDebug(), "No pointers on touchscreen %d, BTN UP event sent.", mFd.get());
381     }
382     return true;
383 }
384 
handleTouchDown(int32_t pointerId,std::chrono::nanoseconds eventTime)385 bool VirtualTouchscreen::handleTouchDown(int32_t pointerId, std::chrono::nanoseconds eventTime) {
386     // When a new pointer is down on the touchscreen, add the pointer id in the corresponding
387     // entry in the unreleased touches map.
388     if (mActivePointers.none()) {
389         // Only sends the BTN Down event when the first pointer on the touchscreen is down.
390         if (!writeInputEvent(EV_KEY, BTN_TOUCH, static_cast<int32_t>(UinputAction::PRESS),
391                              eventTime)) {
392             return false;
393         }
394         ALOGD_IF(isDebug(), "First pointer %d down under touchscreen %d, BTN DOWN event sent",
395                  pointerId, mFd.get());
396     }
397 
398     mActivePointers.set(pointerId);
399     ALOGD_IF(isDebug(), "Added pointer %d under touchscreen %d in the map", pointerId, mFd.get());
400     if (!writeInputEvent(EV_ABS, ABS_MT_TRACKING_ID, static_cast<int32_t>(pointerId), eventTime)) {
401         return false;
402     }
403     return true;
404 }
405 
406 // --- VirtualStylus ---
407 const std::map<int, int> VirtualStylus::TOOL_TYPE_MAPPING = {
408         {AMOTION_EVENT_TOOL_TYPE_STYLUS, BTN_TOOL_PEN},
409         {AMOTION_EVENT_TOOL_TYPE_ERASER, BTN_TOOL_RUBBER},
410 };
411 
412 // Button code mapping from https://source.android.com/devices/input/touch-devices
413 const std::map<int, int> VirtualStylus::BUTTON_CODE_MAPPING = {
414         {AMOTION_EVENT_BUTTON_STYLUS_PRIMARY, BTN_STYLUS},
415         {AMOTION_EVENT_BUTTON_STYLUS_SECONDARY, BTN_STYLUS2},
416 };
417 
VirtualStylus(unique_fd fd)418 VirtualStylus::VirtualStylus(unique_fd fd)
419       : VirtualInputDevice(std::move(fd)), mIsStylusDown(false) {}
420 
~VirtualStylus()421 VirtualStylus::~VirtualStylus() {}
422 
writeMotionEvent(int32_t toolType,int32_t action,int32_t locationX,int32_t locationY,int32_t pressure,int32_t tiltX,int32_t tiltY,std::chrono::nanoseconds eventTime)423 bool VirtualStylus::writeMotionEvent(int32_t toolType, int32_t action, int32_t locationX,
424                                      int32_t locationY, int32_t pressure, int32_t tiltX,
425                                      int32_t tiltY, std::chrono::nanoseconds eventTime) {
426     auto actionIterator = VirtualTouchscreen::TOUCH_ACTION_MAPPING.find(action);
427     if (actionIterator == VirtualTouchscreen::TOUCH_ACTION_MAPPING.end()) {
428         ALOGE("Unsupported action passed for stylus: %d.", action);
429         return false;
430     }
431     UinputAction uinputAction = actionIterator->second;
432     auto toolTypeIterator = TOOL_TYPE_MAPPING.find(toolType);
433     if (toolTypeIterator == TOOL_TYPE_MAPPING.end()) {
434         ALOGE("Unsupported tool type passed for stylus: %d.", toolType);
435         return false;
436     }
437     uint16_t tool = static_cast<uint16_t>(toolTypeIterator->second);
438     if (uinputAction == UinputAction::PRESS && !handleStylusDown(tool, eventTime)) {
439         return false;
440     }
441     if (!mIsStylusDown) {
442         ALOGE("Action UP or MOVE received with no prior action DOWN for stylus %d.", mFd.get());
443         return false;
444     }
445     if (uinputAction == UinputAction::RELEASE && !handleStylusUp(tool, eventTime)) {
446         return false;
447     }
448     if (!writeInputEvent(EV_ABS, ABS_X, locationX, eventTime)) {
449         ALOGE("Unsupported x-axis location passed for stylus: %d.", locationX);
450         return false;
451     }
452     if (!writeInputEvent(EV_ABS, ABS_Y, locationY, eventTime)) {
453         ALOGE("Unsupported y-axis location passed for stylus: %d.", locationY);
454         return false;
455     }
456     if (!writeInputEvent(EV_ABS, ABS_TILT_X, tiltX, eventTime)) {
457         ALOGE("Unsupported x-axis tilt passed for stylus: %d.", tiltX);
458         return false;
459     }
460     if (!writeInputEvent(EV_ABS, ABS_TILT_Y, tiltY, eventTime)) {
461         ALOGE("Unsupported y-axis tilt passed for stylus: %d.", tiltY);
462         return false;
463     }
464     if (!writeInputEvent(EV_ABS, ABS_PRESSURE, pressure, eventTime)) {
465         ALOGE("Unsupported pressure passed for stylus: %d.", pressure);
466         return false;
467     }
468     if (!writeInputEvent(EV_SYN, SYN_REPORT, 0, eventTime)) {
469         ALOGE("Failed to write SYN_REPORT for stylus motion event.");
470         return false;
471     }
472     return true;
473 }
474 
writeButtonEvent(int32_t androidButtonCode,int32_t androidAction,std::chrono::nanoseconds eventTime)475 bool VirtualStylus::writeButtonEvent(int32_t androidButtonCode, int32_t androidAction,
476                                      std::chrono::nanoseconds eventTime) {
477     return writeEvKeyEvent(androidButtonCode, androidAction, BUTTON_CODE_MAPPING,
478                            VirtualMouse::BUTTON_ACTION_MAPPING, eventTime);
479 }
480 
handleStylusDown(uint16_t tool,std::chrono::nanoseconds eventTime)481 bool VirtualStylus::handleStylusDown(uint16_t tool, std::chrono::nanoseconds eventTime) {
482     if (mIsStylusDown) {
483         ALOGE("Repetitive action DOWN event received for a stylus that is already down.");
484         return false;
485     }
486     if (!writeInputEvent(EV_KEY, tool, static_cast<int32_t>(UinputAction::PRESS), eventTime)) {
487         ALOGE("Failed to write EV_KEY for stylus tool type: %u.", tool);
488         return false;
489     }
490     if (!writeInputEvent(EV_KEY, BTN_TOUCH, static_cast<int32_t>(UinputAction::PRESS), eventTime)) {
491         ALOGE("Failed to write BTN_TOUCH for stylus press.");
492         return false;
493     }
494     mIsStylusDown = true;
495     return true;
496 }
497 
handleStylusUp(uint16_t tool,std::chrono::nanoseconds eventTime)498 bool VirtualStylus::handleStylusUp(uint16_t tool, std::chrono::nanoseconds eventTime) {
499     if (!writeInputEvent(EV_KEY, tool, static_cast<int32_t>(UinputAction::RELEASE), eventTime)) {
500         ALOGE("Failed to write EV_KEY for stylus tool type: %u.", tool);
501         return false;
502     }
503     if (!writeInputEvent(EV_KEY, BTN_TOUCH, static_cast<int32_t>(UinputAction::RELEASE),
504                          eventTime)) {
505         ALOGE("Failed to write BTN_TOUCH for stylus release.");
506         return false;
507     }
508     mIsStylusDown = false;
509     return true;
510 }
511 
512 } // namespace android
513