On Mon, Mar 15, 2021 at 3:30 PM Greg Kroah-Hartman
<gregkh@xxxxxxxxxxxxxxxxxxx> wrote:
>
> On Mon, Mar 15, 2021 at 02:58:11PM +0800, Zhai Zhaoxuan wrote:
> > On Sat, Mar 13, 2021 at 9:07 PM Greg Kroah-Hartman
> > <gregkh@xxxxxxxxxxxxxxxxxxx> wrote:
> > >
> > > On Sat, Mar 13, 2021 at 02:32:46PM +0800, Zhai Zhaoxuan wrote:
> > > > Hi Dmitry and Greg,
> > > >
> > > > I recently started making a keyboard utility. It basically helps the
> > > > user press some keys based on a user script.
> > > > So I tried to use the "uinput" driver to help me send keys to the kernel.
> > > >
> > > > Due to any key and combination can be requested by the user script, I
> > > > tried to enable all KEYBIT on the uinput device. But it fails.
> > > > And more accurate, using a binary search, it seems that I am unable to
> > > > enable more than 568 keys.
> > >
> > > As that's not a "real" device, that makes sense :)
> > >
> > > > The KEY_MAX (defined in linux/input-event-codes.h) is 0x2ff. So it
> > > > should be ok to enable 767 keys. The uinput device should not fail
> > > > with only 568 keys.
> > > >
> > > > I read system logs. The log shows that the new input device fails due
> > > > to systemd-udevd trying to read
> > > > `/sys/devices/virtual/input/input4/uevent`, but this file is empty
> > > > unexpectedly.
> > > >
> > > > Then ,I searched on the web about this and found a bug opened in
> > > > 2016-05-24 by Markus:
> > > > https://bugzilla.kernel.org/show_bug.cgi?id=118861
> > > > The status of this bug is still NEW.
> > > >
> > > > I tried to debug the kernel. And I got something that may be useful.
> > > > The "uevent" shows empty, because a -ENOMEM error returns by
> > > > `input_add_uevent_modalias_var`.
> > > > And this function returns -ENOMEM, because the `buf` on `struct
> > > > kobj_uevent_env` is not enough.
> > > >
> > > > The size of `buf` is 2048 (UEVENT_BUFFER_SIZE). According to the
> > > > MODALIAS encoding algorithm (input_print_modalias_bits), if we allow
> > > > all 0x2ff keys to be enabled on the
> > > > uinput device, the buffer should have at least 2477 bytes. (2477 = 3
> > > > * (0xff - 0x71 + 1) + 4 * 0x200)
> > > > 2048 is smaller than 2477, so it fails.
> > > >
> > > > I have tried to set UEVENT_BUFFER_SIZE to 4096. After that,
> > > > everythings seems ok. The `/sys/devices/virtual/input/input4/uevent`
> > > > can show its content correctly. (See the attachment uevent.txt)
> > > >
> > > > Since this change is related to the core feature kobject which is used
> > > > everywhere in the kernel, I don't know if doubling the
> > > > UEVENT_BUFFER_SIZE is the best way to fix it, or if it will cause
> > > > other serious problems.
> > > > Or maybe we can use a dynamic buffer size in `struct kobj_uevent_env`.
> > > >
> > > >
> > > > Thank you,
> > > > Zhai Zhaoxuan
> > >
> > > > PRODUCT=3/1234/5678/0
> > > > NAME="Example device"
> > > > PROP=0
> > > > EV=3
> > > > KEY=7fffffffffffffff ffffffffffffffff ffffffffffffffff ffffffffffffffff ffffffffffffffff ffffffffffffffff ffffffffffffffff ffffffffffffffff ffffffffffffffff ffffffffffffffff ffffffffffffffff fffffffffffffffe
> > > > MODALIAS=input:b0003v1234p5678e0000-e0,1,k71,72,73,74,75,76,77,78,79,7A,7B,7C,7D,7E,7F,80,81,82,83,84,85,86,87,88,89,8A,8B,8C,8D,8E,8F,90,91,92,93,94,95,96,97,98,99,9A,9B,9C,9D,9E,9F,A0,A1,A2,A3,A4,A5,A6,A7,A8,A9,AA,AB,AC,AD,AE,AF,B0,B1,B2,B3,B4,B5,B6,B7,B8,B9,BA,BB,BC,BD,BE,BF,C0,C1,C2,C3,C4,C5,C6,C7,C8,C9,CA,CB,CC,CD,CE,CF,D0,D1,D2,D3,D4,D5,D6,D7,D8,D9,DA,DB,DC,DD,DE,DF,E0,E1,E2,E3,E4,E5,E6,E7,E8,E9,EA,EB,EC,ED,EE,EF,F0,F1,F2,F3,F4,F5,F6,F7,F8,F9,FA,FB,FC,FD,FE,FF,100,101,102,103,104,105,106,107,108,109,10A,10B,10C,10D,10E,10F,110,111,112,113,114,115,116,117,118,119,11A,11B,11C,11D,11E,11F,120,121,122,123,124,125,126,127,128,129,12A,12B,12C,12D,12E,12F,130,131,132,133,134,135,136,137,138,139,13A,13B,13C,13D,13E,13F,140,141,142,143,144,145,146,147,148,149,14A,14B,14C,14D,14E,14F,150,151,152,153,154,155,156,157,158,159,15A,15B,15C,15D,15E,15F,160,161,162,163,164,165,166,167,168,169,16A,16B,16C,16D,16E,16F,170,171,172,173,174,175,176,177,178,179,17A,17B,17C,17D,17E,17F,180,181,182,183,184,185,186,187,188,189,18A,18B,18C,18D,18E,18F,190,191,192,193,194,195,196,197,198,199,19A,19B,19C,19D,19E,19F,1A0,1A1,1A2,1A3,1A4,1A5,1A6,1A7,1A8,1A9,1AA,1AB,1AC,1AD,1AE,1AF,1B0,1B1,1B2,1B3,1B4,1B5,1B6,1B7,1B8,1B9,1BA,1BB,1BC,1BD,1BE,1BF,1C0,1C1,1C2,1C3,1C4,1C5,1C6,1C7,1C8,1C9,1CA,1CB,1CC,1CD,1CE,1CF,1D0,1D1,1D2,1D3,1D4,1D5,1D6,1D7,1D8,1D9,1DA,1DB,1DC,1DD,1DE,1DF,1E0,1E1,1E2,1E3,1E4,1E5,1E6,1E7,1E8,1E9,1EA,1EB,1EC,1ED,1EE,1EF,1F0,1F1,1F2,1F3,1F4,1F5,1F6,1F7,1F8,1F9,1FA,1FB,1FC,1FD,1FE,1FF,200,201,202,203,204,205,206,207,208,209,20A,20B,20C,20D,20E,20F,210,211,212,213,214,215,216,217,218,219,21A,21B,21C,21D,21E,21F,220,221,222,223,224,225,226,227,228,229,22A,22B,22C,22D,22E,22F,230,231,232,233,234,235,236,237,238,239,23A,23B,23C,23D,23E,23F,240,241,242,243,244,245,246,247,248,249,24A,24B,24C,24D,24E,24F,250,251,252,253,254,255,256,257,258,259,25A,25B,25C,25D,25E,25F,260,261,262,263,264,265,266,267,268,269,26A,26B,26C,26D,26E,26F,270,271,272,273,274,275,276,277,278,279,27A,27B,27C,27D,27E,27F,280,281,282,283,284,285,286,287,288,289,28A,28B,28C,28D,28E,28F,290,291,292,293,294,295,296,297,298,299,29A,29B,29C,29D,29E,29F,2A0,2A1,2A2,2A3,2A4,2A5,2A6,2A7,2A8,2A9,2AA,2AB,2AC,2AD,2AE,2AF,2B0,2B1,2B2,2B3,2B4,2B5,2B6,2B7,2B8,2B9,2BA,2BB,2BC,2BD,2BE,2BF,2C0,2C1,2C2,2C3,2C4,2C5,2C6,2C7,2C8,2C9,2CA,2CB,2CC,2CD,2CE,2CF,2D0,2D1,2D2,2D3,2D4,2D5,2D6,2D7,2D8,2D9,2DA,2DB,2DC,2DD,2DE,2DF,2E0,2E1,2E2,2E3,2E4,2E5,2E6,2E7,2E8,2E9,2EA,2EB,2EC,2ED,2EE,2EF,2F0,2F1,2F2,2F3,2F4,2F5,2F6,2F7,2F8,2F9,2FA,2FB,2FC,2FD,2FE,ramlsfw
> > > >
> > >
> > > What about encoding the keys as ranges instead of individual ones, would
> > > that make more sense?
> >
> > I think this solution is ok in most cases.
> >
> >
> > But, just a notice, MODALIAS may be used in user code (such as hwdb in
> > /lib/udev/hwdb.d). For example, the user may have a pattern "k*74*" in
> > hwdb to match the new input device which has a POWER button (0x74 is
> > the key code of power button). Then, the user could use udev to run
> > some programs, when an input device with power button has been added.
> >
> > If we use a "range" to describe the keys, the user may be unable to
> > detect the power button with only hwdb. They have to move the matching
> > code into their own programs.
>
> Yeah, you are right, that's not going to work, I didn't realize that
> this was a modprobe matching field, but should have.
>
> I don't mind bumping up the size of the uevent buffer, but just how
> realistic is this device "in the real world"? What does offering up a
> device with that many keys actually provide userspace with? What
> functionality does it allow that we do not have today?
In the real world, I think, it is nearly impossible that a physical
device contains so many keys or buttons.
But I think a virtual device may need this. Such as a server remote
management card, it simulates a virtual keyboard,
registers keys and forwards all keys from user's computer to server.
And the user's computer may have any keys. So the card needs to
register all possible keys and send them to the kernel.
I have tried to register only all **known** keys instead of all keys,
but it still fails on the kernel.
(The userspace source file has been placed in attachment.)
> What functionality does it allow that we do not have today?
If programs are unable to register all known keys on only 1 uinput
device, programs have to register
keys on two or more devices. But this may result in unexpected behavior.
For example, the program registers Key A on device1, and registers Key
B on device2.
When the program needs to send a key combination A+B to a target
application, it has to:
1. emit Key A down on device 1
2. emit Key B down on device 2
3. SYN_REPORT on device 1
4. SYN_REPORT on device 2
5. emit Key A up on device 1
6. emit Key B up on device 2
7. SYN_REPORT on device 1
8. SYN_REPORT on device 2
Then, the target application polls input events on both devices 1 & 2.
It reads on device 1, and gets Key A pressed down and then released,
so it does feature A.
Then, it reads on device 2, and gets Key B pressed down and then
released, so it does feature B.
Finally, the target application loses the A+B key combination.
If the program has a uinput device with Key A and Key B enabled, the
program can do this:
1. emit Key A down on device 1
2. emit Key B down on device 1
3. SYN_REPORT on device 1
4. emit Key A up on device 1
5. emit Key B up on device 1
3. SYN_REPORT on device 1
The target application has no chance to lose the key combination.
>
> If you change UEVENT_BUFFER_SIZE to be larger, does all of the problems
> go away? This is a short-lived memory buffer, there should not be any
> real issue with increasing it as the memory is used and then freed
> quickly.
I will do more tests about uinput on the modified kernel, and see if
there is still something broken.
But please wait for me some time. I don’t have much time on that
keyboard utility. Since I have a 996 working. :(
>
> thanks,
>
> greg k-h
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <unistd.h>
#include <errno.h>
#include <fcntl.h>
#include <linux/uinput.h>
static int known_keys[] = {
KEY_ESC,
KEY_1,
KEY_2,
KEY_3,
KEY_4,
KEY_5,
KEY_6,
KEY_7,
KEY_8,
KEY_9,
KEY_0,
KEY_MINUS,
KEY_EQUAL,
KEY_BACKSPACE,
KEY_TAB,
KEY_Q,
KEY_W,
KEY_E,
KEY_R,
KEY_T,
KEY_Y,
KEY_U,
KEY_I,
KEY_O,
KEY_P,
KEY_LEFTBRACE,
KEY_RIGHTBRACE,
KEY_ENTER,
KEY_LEFTCTRL,
KEY_A,
KEY_S,
KEY_D,
KEY_F,
KEY_G,
KEY_H,
KEY_J,
KEY_K,
KEY_L,
KEY_SEMICOLON,
KEY_APOSTROPHE,
KEY_GRAVE,
KEY_LEFTSHIFT,
KEY_BACKSLASH,
KEY_Z,
KEY_X,
KEY_C,
KEY_V,
KEY_B,
KEY_N,
KEY_M,
KEY_COMMA,
KEY_DOT,
KEY_SLASH,
KEY_RIGHTSHIFT,
KEY_KPASTERISK,
KEY_LEFTALT,
KEY_SPACE,
KEY_CAPSLOCK,
KEY_F1,
KEY_F2,
KEY_F3,
KEY_F4,
KEY_F5,
KEY_F6,
KEY_F7,
KEY_F8,
KEY_F9,
KEY_F10,
KEY_NUMLOCK,
KEY_SCROLLLOCK,
KEY_KP7,
KEY_KP8,
KEY_KP9,
KEY_KPMINUS,
KEY_KP4,
KEY_KP5,
KEY_KP6,
KEY_KPPLUS,
KEY_KP1,
KEY_KP2,
KEY_KP3,
KEY_KP0,
KEY_KPDOT,
KEY_ZENKAKUHANKAKU,
KEY_102ND,
KEY_F11,
KEY_F12,
KEY_RO,
KEY_KATAKANA,
KEY_HIRAGANA,
KEY_HENKAN,
KEY_KATAKANAHIRAGANA,
KEY_MUHENKAN,
KEY_KPJPCOMMA,
KEY_KPENTER,
KEY_RIGHTCTRL,
KEY_KPSLASH,
KEY_SYSRQ,
KEY_RIGHTALT,
KEY_LINEFEED,
KEY_HOME,
KEY_UP,
KEY_PAGEUP,
KEY_LEFT,
KEY_RIGHT,
KEY_END,
KEY_DOWN,
KEY_PAGEDOWN,
KEY_INSERT,
KEY_DELETE,
KEY_MACRO,
KEY_MUTE,
KEY_VOLUMEDOWN,
KEY_VOLUMEUP,
KEY_POWER,
KEY_KPEQUAL,
KEY_KPPLUSMINUS,
KEY_PAUSE,
KEY_SCALE,
KEY_KPCOMMA,
KEY_HANGEUL,
KEY_HANGUEL,
KEY_HANJA,
KEY_YEN,
KEY_LEFTMETA,
KEY_RIGHTMETA,
KEY_COMPOSE,
KEY_STOP,
KEY_AGAIN,
KEY_PROPS,
KEY_UNDO,
KEY_FRONT,
KEY_COPY,
KEY_OPEN,
KEY_PASTE,
KEY_FIND,
KEY_CUT,
KEY_HELP,
KEY_MENU,
KEY_CALC,
KEY_SETUP,
KEY_SLEEP,
KEY_WAKEUP,
KEY_FILE,
KEY_SENDFILE,
KEY_DELETEFILE,
KEY_XFER,
KEY_PROG1,
KEY_PROG2,
KEY_WWW,
KEY_MSDOS,
KEY_COFFEE,
KEY_SCREENLOCK,
KEY_ROTATE_DISPLAY,
KEY_DIRECTION,
KEY_CYCLEWINDOWS,
KEY_MAIL,
KEY_BOOKMARKS,
KEY_COMPUTER,
KEY_BACK,
KEY_FORWARD,
KEY_CLOSECD,
KEY_EJECTCD,
KEY_EJECTCLOSECD,
KEY_NEXTSONG,
KEY_PLAYPAUSE,
KEY_PREVIOUSSONG,
KEY_STOPCD,
KEY_RECORD,
KEY_REWIND,
KEY_PHONE,
KEY_ISO,
KEY_CONFIG,
KEY_HOMEPAGE,
KEY_REFRESH,
KEY_EXIT,
KEY_MOVE,
KEY_EDIT,
KEY_SCROLLUP,
KEY_SCROLLDOWN,
KEY_KPLEFTPAREN,
KEY_KPRIGHTPAREN,
KEY_NEW,
KEY_REDO,
KEY_F13,
KEY_F14,
KEY_F15,
KEY_F16,
KEY_F17,
KEY_F18,
KEY_F19,
KEY_F20,
KEY_F21,
KEY_F22,
KEY_F23,
KEY_F24,
KEY_PLAYCD,
KEY_PAUSECD,
KEY_PROG3,
KEY_PROG4,
KEY_DASHBOARD,
KEY_SUSPEND,
KEY_CLOSE,
KEY_PLAY,
KEY_FASTFORWARD,
KEY_BASSBOOST,
KEY_PRINT,
KEY_HP,
KEY_CAMERA,
KEY_SOUND,
KEY_QUESTION,
KEY_EMAIL,
KEY_CHAT,
KEY_SEARCH,
KEY_CONNECT,
KEY_FINANCE,
KEY_SPORT,
KEY_SHOP,
KEY_ALTERASE,
KEY_CANCEL,
KEY_BRIGHTNESSDOWN,
KEY_BRIGHTNESSUP,
KEY_MEDIA,
KEY_SWITCHVIDEOMODE,
KEY_KBDILLUMTOGGLE,
KEY_KBDILLUMDOWN,
KEY_KBDILLUMUP,
KEY_SEND,
KEY_REPLY,
KEY_FORWARDMAIL,
KEY_SAVE,
KEY_DOCUMENTS,
KEY_BATTERY,
KEY_BLUETOOTH,
KEY_WLAN,
KEY_UWB,
KEY_UNKNOWN,
KEY_VIDEO_NEXT,
KEY_VIDEO_PREV,
KEY_BRIGHTNESS_CYCLE,
KEY_BRIGHTNESS_AUTO,
KEY_BRIGHTNESS_ZERO,
KEY_DISPLAY_OFF,
KEY_WWAN,
KEY_WIMAX,
KEY_RFKILL,
KEY_MICMUTE,
BTN_MISC,
BTN_0,
BTN_1,
BTN_2,
BTN_3,
BTN_4,
BTN_5,
BTN_6,
BTN_7,
BTN_8,
BTN_9,
BTN_MOUSE,
BTN_LEFT,
BTN_RIGHT,
BTN_MIDDLE,
BTN_SIDE,
BTN_EXTRA,
BTN_FORWARD,
BTN_BACK,
BTN_TASK,
BTN_JOYSTICK,
BTN_TRIGGER,
BTN_THUMB,
BTN_THUMB2,
BTN_TOP,
BTN_TOP2,
BTN_PINKIE,
BTN_BASE,
BTN_BASE2,
BTN_BASE3,
BTN_BASE4,
BTN_BASE5,
BTN_BASE6,
BTN_DEAD,
BTN_GAMEPAD,
BTN_SOUTH,
BTN_A,
BTN_EAST,
BTN_B,
BTN_C,
BTN_NORTH,
BTN_X,
BTN_WEST,
BTN_Y,
BTN_Z,
BTN_TL,
BTN_TR,
BTN_TL2,
BTN_TR2,
BTN_SELECT,
BTN_START,
BTN_MODE,
BTN_THUMBL,
BTN_THUMBR,
BTN_DIGI,
BTN_TOOL_PEN,
BTN_TOOL_RUBBER,
BTN_TOOL_BRUSH,
BTN_TOOL_PENCIL,
BTN_TOOL_AIRBRUSH,
BTN_TOOL_FINGER,
BTN_TOOL_MOUSE,
BTN_TOOL_LENS,
BTN_TOOL_QUINTTAP,
BTN_STYLUS3,
BTN_TOUCH,
BTN_STYLUS,
BTN_STYLUS2,
BTN_TOOL_DOUBLETAP,
BTN_TOOL_TRIPLETAP,
BTN_TOOL_QUADTAP,
BTN_WHEEL,
BTN_GEAR_DOWN,
BTN_GEAR_UP,
KEY_OK,
KEY_SELECT,
KEY_GOTO,
KEY_CLEAR,
KEY_POWER2,
KEY_OPTION,
KEY_INFO,
KEY_TIME,
KEY_VENDOR,
KEY_ARCHIVE,
KEY_PROGRAM,
KEY_CHANNEL,
KEY_FAVORITES,
KEY_EPG,
KEY_PVR,
KEY_MHP,
KEY_LANGUAGE,
KEY_TITLE,
KEY_SUBTITLE,
KEY_ANGLE,
KEY_FULL_SCREEN,
KEY_ZOOM,
KEY_MODE,
KEY_KEYBOARD,
KEY_ASPECT_RATIO,
KEY_SCREEN,
KEY_PC,
KEY_TV,
KEY_TV2,
KEY_VCR,
KEY_VCR2,
KEY_SAT,
KEY_SAT2,
KEY_CD,
KEY_TAPE,
KEY_RADIO,
KEY_TUNER,
KEY_PLAYER,
KEY_TEXT,
KEY_DVD,
KEY_AUX,
KEY_MP3,
KEY_AUDIO,
KEY_VIDEO,
KEY_DIRECTORY,
KEY_LIST,
KEY_MEMO,
KEY_CALENDAR,
KEY_RED,
KEY_GREEN,
KEY_YELLOW,
KEY_BLUE,
KEY_CHANNELUP,
KEY_CHANNELDOWN,
KEY_FIRST,
KEY_LAST,
KEY_AB,
KEY_NEXT,
KEY_RESTART,
KEY_SLOW,
KEY_SHUFFLE,
KEY_BREAK,
KEY_PREVIOUS,
KEY_DIGITS,
KEY_TEEN,
KEY_TWEN,
KEY_VIDEOPHONE,
KEY_GAMES,
KEY_ZOOMIN,
KEY_ZOOMOUT,
KEY_ZOOMRESET,
KEY_WORDPROCESSOR,
KEY_EDITOR,
KEY_SPREADSHEET,
KEY_GRAPHICSEDITOR,
KEY_PRESENTATION,
KEY_DATABASE,
KEY_NEWS,
KEY_VOICEMAIL,
KEY_ADDRESSBOOK,
KEY_MESSENGER,
KEY_DISPLAYTOGGLE,
KEY_BRIGHTNESS_TOGGLE,
KEY_SPELLCHECK,
KEY_LOGOFF,
KEY_DOLLAR,
KEY_EURO,
KEY_FRAMEBACK,
KEY_FRAMEFORWARD,
KEY_CONTEXT_MENU,
KEY_MEDIA_REPEAT,
KEY_10CHANNELSUP,
KEY_10CHANNELSDOWN,
KEY_IMAGES,
KEY_DEL_EOL,
KEY_DEL_EOS,
KEY_INS_LINE,
KEY_DEL_LINE,
KEY_FN,
KEY_FN_ESC,
KEY_FN_F1,
KEY_FN_F2,
KEY_FN_F3,
KEY_FN_F4,
KEY_FN_F5,
KEY_FN_F6,
KEY_FN_F7,
KEY_FN_F8,
KEY_FN_F9,
KEY_FN_F10,
KEY_FN_F11,
KEY_FN_F12,
KEY_FN_1,
KEY_FN_2,
KEY_FN_D,
KEY_FN_E,
KEY_FN_F,
KEY_FN_S,
KEY_FN_B,
KEY_BRL_DOT1,
KEY_BRL_DOT2,
KEY_BRL_DOT3,
KEY_BRL_DOT4,
KEY_BRL_DOT5,
KEY_BRL_DOT6,
KEY_BRL_DOT7,
KEY_BRL_DOT8,
KEY_BRL_DOT9,
KEY_BRL_DOT10,
KEY_NUMERIC_0,
KEY_NUMERIC_1,
KEY_NUMERIC_2,
KEY_NUMERIC_3,
KEY_NUMERIC_4,
KEY_NUMERIC_5,
KEY_NUMERIC_6,
KEY_NUMERIC_7,
KEY_NUMERIC_8,
KEY_NUMERIC_9,
KEY_NUMERIC_STAR,
KEY_NUMERIC_POUND,
KEY_NUMERIC_A,
KEY_NUMERIC_B,
KEY_NUMERIC_C,
KEY_NUMERIC_D,
KEY_CAMERA_FOCUS,
KEY_WPS_BUTTON,
KEY_TOUCHPAD_TOGGLE,
KEY_TOUCHPAD_ON,
KEY_TOUCHPAD_OFF,
KEY_CAMERA_ZOOMIN,
KEY_CAMERA_ZOOMOUT,
KEY_CAMERA_UP,
KEY_CAMERA_DOWN,
KEY_CAMERA_LEFT,
KEY_CAMERA_RIGHT,
KEY_ATTENDANT_ON,
KEY_ATTENDANT_OFF,
KEY_ATTENDANT_TOGGLE,
KEY_LIGHTS_TOGGLE,
BTN_DPAD_UP,
BTN_DPAD_DOWN,
BTN_DPAD_LEFT,
BTN_DPAD_RIGHT,
KEY_ALS_TOGGLE,
KEY_ROTATE_LOCK_TOGGLE,
KEY_BUTTONCONFIG,
KEY_TASKMANAGER,
KEY_JOURNAL,
KEY_CONTROLPANEL,
KEY_APPSELECT,
KEY_SCREENSAVER,
KEY_VOICECOMMAND,
KEY_ASSISTANT,
KEY_KBD_LAYOUT_NEXT,
KEY_BRIGHTNESS_MIN,
KEY_BRIGHTNESS_MAX,
KEY_KBDINPUTASSIST_PREV,
KEY_KBDINPUTASSIST_NEXT,
KEY_KBDINPUTASSIST_PREVGROUP,
KEY_KBDINPUTASSIST_NEXTGROUP,
KEY_KBDINPUTASSIST_ACCEPT,
KEY_KBDINPUTASSIST_CANCEL,
KEY_RIGHT_UP,
KEY_RIGHT_DOWN,
KEY_LEFT_UP,
KEY_LEFT_DOWN,
KEY_ROOT_MENU,
KEY_MEDIA_TOP_MENU,
KEY_NUMERIC_11,
KEY_NUMERIC_12,
KEY_AUDIO_DESC,
KEY_3D_MODE,
KEY_NEXT_FAVORITE,
KEY_STOP_RECORD,
KEY_PAUSE_RECORD,
KEY_VOD,
KEY_UNMUTE,
KEY_FASTREVERSE,
KEY_SLOWREVERSE,
KEY_DATA,
KEY_ONSCREEN_KEYBOARD,
KEY_PRIVACY_SCREEN_TOGGLE,
KEY_SELECTIVE_SCREENSHOT,
KEY_MACRO1,
KEY_MACRO2,
KEY_MACRO3,
KEY_MACRO4,
KEY_MACRO5,
KEY_MACRO6,
KEY_MACRO7,
KEY_MACRO8,
KEY_MACRO9,
KEY_MACRO10,
KEY_MACRO11,
KEY_MACRO12,
KEY_MACRO13,
KEY_MACRO14,
KEY_MACRO15,
KEY_MACRO16,
KEY_MACRO17,
KEY_MACRO18,
KEY_MACRO19,
KEY_MACRO20,
KEY_MACRO21,
KEY_MACRO22,
KEY_MACRO23,
KEY_MACRO24,
KEY_MACRO25,
KEY_MACRO26,
KEY_MACRO27,
KEY_MACRO28,
KEY_MACRO29,
KEY_MACRO30,
KEY_MACRO_RECORD_START,
KEY_MACRO_RECORD_STOP,
KEY_MACRO_PRESET_CYCLE,
KEY_MACRO_PRESET1,
KEY_MACRO_PRESET2,
KEY_MACRO_PRESET3,
KEY_KBD_LCD_MENU1,
KEY_KBD_LCD_MENU2,
KEY_KBD_LCD_MENU3,
KEY_KBD_LCD_MENU4,
KEY_KBD_LCD_MENU5,
BTN_TRIGGER_HAPPY,
BTN_TRIGGER_HAPPY1,
BTN_TRIGGER_HAPPY2,
BTN_TRIGGER_HAPPY3,
BTN_TRIGGER_HAPPY4,
BTN_TRIGGER_HAPPY5,
BTN_TRIGGER_HAPPY6,
BTN_TRIGGER_HAPPY7,
BTN_TRIGGER_HAPPY8,
BTN_TRIGGER_HAPPY9,
BTN_TRIGGER_HAPPY10,
BTN_TRIGGER_HAPPY11,
BTN_TRIGGER_HAPPY12,
BTN_TRIGGER_HAPPY13,
BTN_TRIGGER_HAPPY14,
BTN_TRIGGER_HAPPY15,
BTN_TRIGGER_HAPPY16,
BTN_TRIGGER_HAPPY17,
BTN_TRIGGER_HAPPY18,
BTN_TRIGGER_HAPPY19,
BTN_TRIGGER_HAPPY20,
BTN_TRIGGER_HAPPY21,
BTN_TRIGGER_HAPPY22,
BTN_TRIGGER_HAPPY23,
BTN_TRIGGER_HAPPY24,
BTN_TRIGGER_HAPPY25,
BTN_TRIGGER_HAPPY26,
BTN_TRIGGER_HAPPY27,
BTN_TRIGGER_HAPPY28,
BTN_TRIGGER_HAPPY29,
BTN_TRIGGER_HAPPY30,
BTN_TRIGGER_HAPPY31,
BTN_TRIGGER_HAPPY32,
BTN_TRIGGER_HAPPY33,
BTN_TRIGGER_HAPPY34,
BTN_TRIGGER_HAPPY35,
BTN_TRIGGER_HAPPY36,
BTN_TRIGGER_HAPPY37,
BTN_TRIGGER_HAPPY38,
BTN_TRIGGER_HAPPY39,
BTN_TRIGGER_HAPPY40,
};
void emit(int fd, int type, int code, int val)
{
struct input_event ie;
ie.type = type;
ie.code = code;
ie.value = val;
/* timestamp values below are ignored */
ie.time.tv_sec = 0;
ie.time.tv_usec = 0;
write(fd, &ie, sizeof(ie));
}
int main(void)
{
struct uinput_setup usetup;
int fd = open("/dev/uinput", O_WRONLY | O_NONBLOCK);
if (fd < 0) {
switch (errno) {
case EACCES:
fprintf(stderr, "Please run this program as root\n");
break;
case ENOENT:
fprintf(stderr, "Please load \"uinput\" module\n");
break;
default:
fprintf(stderr, "Error open /dev/uinput: %s\n", strerror(errno));
break;
}
exit(1);
}
/*
* The ioctls below will enable the device that is about to be
* created, to pass key events, in this case the space key.
*/
ioctl(fd, UI_SET_EVBIT, EV_KEY);
for (int i = 0; i < sizeof(known_keys) / sizeof(*known_keys); i++) {
ioctl(fd, UI_SET_KEYBIT, known_keys[i]);
}
printf("%d known keys registered\n", sizeof(known_keys)/ sizeof(*known_keys));
memset(&usetup, 0, sizeof(usetup));
usetup.id.bustype = BUS_USB;
usetup.id.vendor = 0x1234; /* sample vendor */
usetup.id.product = 0x5678; /* sample product */
strcpy(usetup.name, "Example device");
ioctl(fd, UI_DEV_SETUP, &usetup);
ioctl(fd, UI_DEV_CREATE);
/*
* Give userspace some time to read the events before we destroy the
* device with UI_DEV_DESTOY.
*/
sleep(1000);
ioctl(fd, UI_DEV_DESTROY);
close(fd);
return 0;
}
