Fixed bug 3157 - Rudimentary touchscreen support in SDL_evdev (supports Raspberry Pi)

tvc

I've spent the last few days implementing touchscreen support in core/linux/SDL_evdev.c. It's fairly rudimentary at the moment, as can be seen from the multiple TODO's and FIXME's littered throughout, but I'm mainly submitting this patch for review. I've tested this patch on my Raspberry Pi 2 with the official touchscreen and it works fantastically, reporting all 10 multitouch points. I'm happy to work on this further, the evdev logic also needs a bit of a cleanup I think (I may have included a few changes). But if it's good enough in its current state to be committed then I'm sure there'd be plenty of people pleased, as currently the only other framework/library that supports touchscreens on the Raspberry Pi is Kivy.

src/core/linux/SDL_evdev.c

@@ -29,10 +29,7 @@
  *             The evtest application is also useful to debug the protocol
  */
 
-
 #include "SDL_evdev.h"
-#define _THIS SDL_EVDEV_PrivateData *_this
-static _THIS = NULL;
 
 #include <sys/stat.h>
 #include <unistd.h>
@@ -43,18 +40,8 @@ static _THIS = NULL;
 #ifdef SDL_INPUT_LINUXKD
 #include <linux/kd.h>
 #include <linux/keyboard.h>
-#endif
-
-
-/* We need this to prevent keystrokes from appear in the console */
-#ifndef KDSKBMUTE
-#define KDSKBMUTE 0x4B51
-#endif
-#ifndef KDSKBMODE
-#define KDSKBMODE 0x4B45
-#endif
-#ifndef K_OFF
-#define K_OFF 0x04
+#include <linux/vt.h>
+#include <linux/tiocl.h> /* for TIOCL_GETSHIFTSTATE */
 #endif
 
 #include "SDL.h"
@@ -63,273 +50,71 @@ static _THIS = NULL;
 #include "../../core/linux/SDL_udev.h"
 #include "SDL_scancode.h"
 #include "../../events/SDL_events_c.h"
+#include "../../events/scancodes_linux.h" /* adds linux_scancode_table */
 
 /* This isn't defined in older Linux kernel headers */
 #ifndef SYN_DROPPED
 #define SYN_DROPPED 3
 #endif
 
+typedef struct SDL_evdevlist_item
+{
+    char *path;
+    int fd;
+    
+    /* TODO: use this for every device, not just touchscreen */
+    int out_of_sync;
+    
+    /* TODO: expand on this to have data for every possible class (mouse,
+       keyboard, touchpad, etc.). Also there's probably some things in here we
+       can pull out to the SDL_evdevlist_item i.e. name */
+    int is_touchscreen;
+    struct {
+        char* name;
+        
+        int min_x, max_x, range_x;
+        int min_y, max_y, range_y;
+        
+        int max_slots;
+        int current_slot;
+        struct {
+            enum {
+                EVDEV_TOUCH_SLOTDELTA_NONE = 0,
+                EVDEV_TOUCH_SLOTDELTA_DOWN,
+                EVDEV_TOUCH_SLOTDELTA_UP,
+                EVDEV_TOUCH_SLOTDELTA_MOVE
+            } delta;
+            int tracking_id;
+            int x, y;
+        } * slots;
+    } * touchscreen_data;
+    
+    struct SDL_evdevlist_item *next;
+} SDL_evdevlist_item;
+
+typedef struct SDL_EVDEV_PrivateData
+{
+    SDL_evdevlist_item *first;
+    SDL_evdevlist_item *last;
+    int num_devices;
+    int ref_count;
+    int console_fd;
+    int kb_mode;
+} SDL_EVDEV_PrivateData;
+
+#define _THIS SDL_EVDEV_PrivateData *_this
+static _THIS = NULL;
+
 static SDL_Scancode SDL_EVDEV_translate_keycode(int keycode);
 static void SDL_EVDEV_sync_device(SDL_evdevlist_item *item);
-static int SDL_EVDEV_device_removed(const char *devpath);
+static int SDL_EVDEV_device_removed(const char *dev_path);
 
 #if SDL_USE_LIBUDEV
-static int SDL_EVDEV_device_added(const char *devpath);
-void SDL_EVDEV_udev_callback(SDL_UDEV_deviceevent udev_type, int udev_class, const char *devpath);
+static int SDL_EVDEV_device_added( const char *dev_path, int udev_class );
+void SDL_EVDEV_udev_callback( SDL_UDEV_deviceevent udev_type, int udev_class,
+    const char *dev_path );
 #endif /* SDL_USE_LIBUDEV */
 
-static SDL_Scancode EVDEV_Keycodes[] = {
-    SDL_SCANCODE_UNKNOWN,       /*  KEY_RESERVED        0 */
-    SDL_SCANCODE_ESCAPE,        /*  KEY_ESC         1 */
-    SDL_SCANCODE_1,             /*  KEY_1           2 */
-    SDL_SCANCODE_2,             /*  KEY_2           3 */
-    SDL_SCANCODE_3,             /*  KEY_3           4 */
-    SDL_SCANCODE_4,             /*  KEY_4           5 */
-    SDL_SCANCODE_5,             /*  KEY_5           6 */
-    SDL_SCANCODE_6,             /*  KEY_6           7 */
-    SDL_SCANCODE_7,             /*  KEY_7           8 */
-    SDL_SCANCODE_8,             /*  KEY_8           9 */
-    SDL_SCANCODE_9,             /*  KEY_9           10 */
-    SDL_SCANCODE_0,             /*  KEY_0           11 */
-    SDL_SCANCODE_MINUS,         /*  KEY_MINUS       12 */
-    SDL_SCANCODE_EQUALS,        /*  KEY_EQUAL       13 */
-    SDL_SCANCODE_BACKSPACE,     /*  KEY_BACKSPACE       14 */
-    SDL_SCANCODE_TAB,           /*  KEY_TAB         15 */
-    SDL_SCANCODE_Q,             /*  KEY_Q           16 */
-    SDL_SCANCODE_W,             /*  KEY_W           17 */
-    SDL_SCANCODE_E,             /*  KEY_E           18 */
-    SDL_SCANCODE_R,             /*  KEY_R           19 */
-    SDL_SCANCODE_T,             /*  KEY_T           20 */
-    SDL_SCANCODE_Y,             /*  KEY_Y           21 */
-    SDL_SCANCODE_U,             /*  KEY_U           22 */
-    SDL_SCANCODE_I,             /*  KEY_I           23 */
-    SDL_SCANCODE_O,             /*  KEY_O           24 */
-    SDL_SCANCODE_P,             /*  KEY_P           25 */
-    SDL_SCANCODE_LEFTBRACKET,   /*  KEY_LEFTBRACE       26 */
-    SDL_SCANCODE_RIGHTBRACKET,  /*  KEY_RIGHTBRACE      27 */
-    SDL_SCANCODE_RETURN,        /*  KEY_ENTER       28 */
-    SDL_SCANCODE_LCTRL,         /*  KEY_LEFTCTRL        29 */
-    SDL_SCANCODE_A,             /*  KEY_A           30 */
-    SDL_SCANCODE_S,             /*  KEY_S           31 */
-    SDL_SCANCODE_D,             /*  KEY_D           32 */
-    SDL_SCANCODE_F,             /*  KEY_F           33 */
-    SDL_SCANCODE_G,             /*  KEY_G           34 */
-    SDL_SCANCODE_H,             /*  KEY_H           35 */
-    SDL_SCANCODE_J,             /*  KEY_J           36 */
-    SDL_SCANCODE_K,             /*  KEY_K           37 */
-    SDL_SCANCODE_L,             /*  KEY_L           38 */
-    SDL_SCANCODE_SEMICOLON,     /*  KEY_SEMICOLON       39 */
-    SDL_SCANCODE_APOSTROPHE,    /*  KEY_APOSTROPHE      40 */
-    SDL_SCANCODE_GRAVE,         /*  KEY_GRAVE       41 */
-    SDL_SCANCODE_LSHIFT,        /*  KEY_LEFTSHIFT       42 */
-    SDL_SCANCODE_BACKSLASH,     /*  KEY_BACKSLASH       43 */
-    SDL_SCANCODE_Z,             /*  KEY_Z           44 */
-    SDL_SCANCODE_X,             /*  KEY_X           45 */
-    SDL_SCANCODE_C,             /*  KEY_C           46 */
-    SDL_SCANCODE_V,             /*  KEY_V           47 */
-    SDL_SCANCODE_B,             /*  KEY_B           48 */
-    SDL_SCANCODE_N,             /*  KEY_N           49 */
-    SDL_SCANCODE_M,             /*  KEY_M           50 */
-    SDL_SCANCODE_COMMA,         /*  KEY_COMMA       51 */
-    SDL_SCANCODE_PERIOD,        /*  KEY_DOT         52 */
-    SDL_SCANCODE_SLASH,         /*  KEY_SLASH       53 */
-    SDL_SCANCODE_RSHIFT,        /*  KEY_RIGHTSHIFT      54 */
-    SDL_SCANCODE_KP_MULTIPLY,   /*  KEY_KPASTERISK      55 */
-    SDL_SCANCODE_LALT,          /*  KEY_LEFTALT     56 */
-    SDL_SCANCODE_SPACE,         /*  KEY_SPACE       57 */
-    SDL_SCANCODE_CAPSLOCK,      /*  KEY_CAPSLOCK        58 */
-    SDL_SCANCODE_F1,            /*  KEY_F1          59 */
-    SDL_SCANCODE_F2,            /*  KEY_F2          60 */
-    SDL_SCANCODE_F3,            /*  KEY_F3          61 */
-    SDL_SCANCODE_F4,            /*  KEY_F4          62 */
-    SDL_SCANCODE_F5,            /*  KEY_F5          63 */
-    SDL_SCANCODE_F6,            /*  KEY_F6          64 */
-    SDL_SCANCODE_F7,            /*  KEY_F7          65 */
-    SDL_SCANCODE_F8,            /*  KEY_F8          66 */
-    SDL_SCANCODE_F9,            /*  KEY_F9          67 */
-    SDL_SCANCODE_F10,           /*  KEY_F10         68 */
-    SDL_SCANCODE_NUMLOCKCLEAR,  /*  KEY_NUMLOCK     69 */
-    SDL_SCANCODE_SCROLLLOCK,    /*  KEY_SCROLLLOCK      70 */
-    SDL_SCANCODE_KP_7,          /*  KEY_KP7         71 */
-    SDL_SCANCODE_KP_8,          /*  KEY_KP8         72 */
-    SDL_SCANCODE_KP_9,          /*  KEY_KP9         73 */
-    SDL_SCANCODE_KP_MINUS,      /*  KEY_KPMINUS     74 */
-    SDL_SCANCODE_KP_4,          /*  KEY_KP4         75 */
-    SDL_SCANCODE_KP_5,          /*  KEY_KP5         76 */
-    SDL_SCANCODE_KP_6,          /*  KEY_KP6         77 */
-    SDL_SCANCODE_KP_PLUS,       /*  KEY_KPPLUS      78 */
-    SDL_SCANCODE_KP_1,          /*  KEY_KP1         79 */
-    SDL_SCANCODE_KP_2,          /*  KEY_KP2         80 */
-    SDL_SCANCODE_KP_3,          /*  KEY_KP3         81 */
-    SDL_SCANCODE_KP_0,          /*  KEY_KP0         82 */
-    SDL_SCANCODE_KP_PERIOD,     /*  KEY_KPDOT       83 */
-    SDL_SCANCODE_UNKNOWN,       /*  84 */
-    SDL_SCANCODE_LANG5,         /*  KEY_ZENKAKUHANKAKU  85 */
-    SDL_SCANCODE_UNKNOWN,       /*  KEY_102ND       86 */
-    SDL_SCANCODE_F11,           /*  KEY_F11         87 */
-    SDL_SCANCODE_F12,           /*  KEY_F12         88 */
-    SDL_SCANCODE_UNKNOWN,       /*  KEY_RO          89 */
-    SDL_SCANCODE_LANG3,         /*  KEY_KATAKANA        90 */
-    SDL_SCANCODE_LANG4,         /*  KEY_HIRAGANA        91 */
-    SDL_SCANCODE_UNKNOWN,       /*  KEY_HENKAN      92 */
-    SDL_SCANCODE_LANG3,         /*  KEY_KATAKANAHIRAGANA    93 */
-    SDL_SCANCODE_UNKNOWN,       /*  KEY_MUHENKAN        94 */
-    SDL_SCANCODE_KP_COMMA,      /*  KEY_KPJPCOMMA       95 */
-    SDL_SCANCODE_KP_ENTER,      /*  KEY_KPENTER     96 */
-    SDL_SCANCODE_RCTRL,         /*  KEY_RIGHTCTRL       97 */
-    SDL_SCANCODE_KP_DIVIDE,     /*  KEY_KPSLASH     98 */
-    SDL_SCANCODE_SYSREQ,        /*  KEY_SYSRQ       99 */
-    SDL_SCANCODE_RALT,          /*  KEY_RIGHTALT        100 */
-    SDL_SCANCODE_UNKNOWN,       /*  KEY_LINEFEED        101 */
-    SDL_SCANCODE_HOME,          /*  KEY_HOME        102 */
-    SDL_SCANCODE_UP,            /*  KEY_UP          103 */
-    SDL_SCANCODE_PAGEUP,        /*  KEY_PAGEUP      104 */
-    SDL_SCANCODE_LEFT,          /*  KEY_LEFT        105 */
-    SDL_SCANCODE_RIGHT,         /*  KEY_RIGHT       106 */
-    SDL_SCANCODE_END,           /*  KEY_END         107 */
-    SDL_SCANCODE_DOWN,          /*  KEY_DOWN        108 */
-    SDL_SCANCODE_PAGEDOWN,      /*  KEY_PAGEDOWN        109 */
-    SDL_SCANCODE_INSERT,        /*  KEY_INSERT      110 */
-    SDL_SCANCODE_DELETE,        /*  KEY_DELETE      111 */
-    SDL_SCANCODE_UNKNOWN,       /*  KEY_MACRO       112 */
-    SDL_SCANCODE_MUTE,          /*  KEY_MUTE        113 */
-    SDL_SCANCODE_VOLUMEDOWN,    /*  KEY_VOLUMEDOWN      114 */
-    SDL_SCANCODE_VOLUMEUP,      /*  KEY_VOLUMEUP        115 */
-    SDL_SCANCODE_POWER,         /*  KEY_POWER       116 SC System Power Down */
-    SDL_SCANCODE_KP_EQUALS,     /*  KEY_KPEQUAL     117 */
-    SDL_SCANCODE_KP_MINUS,      /*  KEY_KPPLUSMINUS     118 */
-    SDL_SCANCODE_PAUSE,         /*  KEY_PAUSE       119 */
-    SDL_SCANCODE_UNKNOWN,       /*  KEY_SCALE       120 AL Compiz Scale (Expose) */
-    SDL_SCANCODE_KP_COMMA,      /*  KEY_KPCOMMA     121 */
-    SDL_SCANCODE_LANG1,         /*  KEY_HANGEUL,KEY_HANGUEL 122 */
-    SDL_SCANCODE_LANG2,         /*  KEY_HANJA       123 */
-    SDL_SCANCODE_INTERNATIONAL3,/*  KEY_YEN         124 */
-    SDL_SCANCODE_LGUI,          /*  KEY_LEFTMETA        125 */
-    SDL_SCANCODE_RGUI,          /*  KEY_RIGHTMETA       126 */
-    SDL_SCANCODE_APPLICATION,   /*  KEY_COMPOSE     127 */
-    SDL_SCANCODE_STOP,          /*  KEY_STOP        128 AC Stop */
-    SDL_SCANCODE_AGAIN,         /*  KEY_AGAIN       129 */
-    SDL_SCANCODE_UNKNOWN,       /*  KEY_PROPS       130 AC Properties */
-    SDL_SCANCODE_UNDO,          /*  KEY_UNDO        131 AC Undo */
-    SDL_SCANCODE_UNKNOWN,       /*  KEY_FRONT       132 */
-    SDL_SCANCODE_COPY,          /*  KEY_COPY        133 AC Copy */
-    SDL_SCANCODE_UNKNOWN,       /*  KEY_OPEN        134 AC Open */
-    SDL_SCANCODE_PASTE,         /*  KEY_PASTE       135 AC Paste */
-    SDL_SCANCODE_FIND,          /*  KEY_FIND        136 AC Search */
-    SDL_SCANCODE_CUT,           /*  KEY_CUT         137 AC Cut */
-    SDL_SCANCODE_HELP,          /*  KEY_HELP        138 AL Integrated Help Center */
-    SDL_SCANCODE_MENU,          /*  KEY_MENU        139 Menu (show menu) */
-    SDL_SCANCODE_CALCULATOR,    /*  KEY_CALC        140 AL Calculator */
-    SDL_SCANCODE_UNKNOWN,       /*  KEY_SETUP       141 */
-    SDL_SCANCODE_SLEEP,         /*  KEY_SLEEP       142 SC System Sleep */
-    SDL_SCANCODE_UNKNOWN,       /*  KEY_WAKEUP      143 System Wake Up */
-    SDL_SCANCODE_UNKNOWN,       /*  KEY_FILE        144 AL Local Machine Browser */
-    SDL_SCANCODE_UNKNOWN,       /*  KEY_SENDFILE        145 */
-    SDL_SCANCODE_UNKNOWN,       /*  KEY_DELETEFILE      146 */
-    SDL_SCANCODE_UNKNOWN,       /*  KEY_XFER        147 */
-    SDL_SCANCODE_APP1,          /*  KEY_PROG1       148 */
-    SDL_SCANCODE_APP1,          /*  KEY_PROG2       149 */
-    SDL_SCANCODE_WWW,           /*  KEY_WWW         150 AL Internet Browser */
-    SDL_SCANCODE_UNKNOWN,       /*  KEY_MSDOS       151 */
-    SDL_SCANCODE_UNKNOWN,       /*  KEY_COFFEE,KEY_SCREENLOCK      152 AL Terminal Lock/Screensaver */
-    SDL_SCANCODE_UNKNOWN,       /*  KEY_DIRECTION       153 */
-    SDL_SCANCODE_UNKNOWN,       /*  KEY_CYCLEWINDOWS    154 */
-    SDL_SCANCODE_MAIL,          /*  KEY_MAIL        155 */
-    SDL_SCANCODE_AC_BOOKMARKS,  /*  KEY_BOOKMARKS       156 AC Bookmarks */
-    SDL_SCANCODE_COMPUTER,      /*  KEY_COMPUTER        157 */
-    SDL_SCANCODE_AC_BACK,       /*  KEY_BACK        158 AC Back */
-    SDL_SCANCODE_AC_FORWARD,    /*  KEY_FORWARD     159 AC Forward */
-    SDL_SCANCODE_UNKNOWN,       /*  KEY_CLOSECD     160 */
-    SDL_SCANCODE_EJECT,         /*  KEY_EJECTCD     161 */
-    SDL_SCANCODE_UNKNOWN,       /*  KEY_EJECTCLOSECD    162 */
-    SDL_SCANCODE_AUDIONEXT,     /*  KEY_NEXTSONG        163 */
-    SDL_SCANCODE_AUDIOPLAY,     /*  KEY_PLAYPAUSE       164 */
-    SDL_SCANCODE_AUDIOPREV,     /*  KEY_PREVIOUSSONG    165 */
-    SDL_SCANCODE_AUDIOSTOP,     /*  KEY_STOPCD      166 */
-    SDL_SCANCODE_UNKNOWN,       /*  KEY_RECORD      167 */
-    SDL_SCANCODE_UNKNOWN,       /*  KEY_REWIND      168 */
-    SDL_SCANCODE_UNKNOWN,       /*  KEY_PHONE       169 Media Select Telephone */
-    SDL_SCANCODE_UNKNOWN,       /*  KEY_ISO         170 */
-    SDL_SCANCODE_UNKNOWN,       /*  KEY_CONFIG      171 AL Consumer Control Configuration */
-    SDL_SCANCODE_AC_HOME,       /*  KEY_HOMEPAGE        172 AC Home */
-    SDL_SCANCODE_AC_REFRESH,    /*  KEY_REFRESH     173 AC Refresh */
-    SDL_SCANCODE_UNKNOWN,       /*  KEY_EXIT        174 AC Exit */
-    SDL_SCANCODE_UNKNOWN,       /*  KEY_MOVE        175 */
-    SDL_SCANCODE_UNKNOWN,       /*  KEY_EDIT        176 */
-    SDL_SCANCODE_UNKNOWN,       /*  KEY_SCROLLUP        177 */
-    SDL_SCANCODE_UNKNOWN,       /*  KEY_SCROLLDOWN      178 */
-    SDL_SCANCODE_KP_LEFTPAREN,  /*  KEY_KPLEFTPAREN     179 */
-    SDL_SCANCODE_KP_RIGHTPAREN, /*  KEY_KPRIGHTPAREN    180 */
-    SDL_SCANCODE_UNKNOWN,       /*  KEY_NEW         181 AC New */
-    SDL_SCANCODE_AGAIN,         /*  KEY_REDO        182 AC Redo/Repeat */
-    SDL_SCANCODE_F13,           /*  KEY_F13         183 */
-    SDL_SCANCODE_F14,           /*  KEY_F14         184 */
-    SDL_SCANCODE_F15,           /*  KEY_F15         185 */
-    SDL_SCANCODE_F16,           /*  KEY_F16         186 */
-    SDL_SCANCODE_F17,           /*  KEY_F17         187 */
-    SDL_SCANCODE_F18,           /*  KEY_F18         188 */
-    SDL_SCANCODE_F19,           /*  KEY_F19         189 */
-    SDL_SCANCODE_F20,           /*  KEY_F20         190 */
-    SDL_SCANCODE_F21,           /*  KEY_F21         191 */
-    SDL_SCANCODE_F22,           /*  KEY_F22         192 */
-    SDL_SCANCODE_F23,           /*  KEY_F23         193 */
-    SDL_SCANCODE_F24,           /*  KEY_F24         194 */
-    SDL_SCANCODE_UNKNOWN,       /*  195 */
-    SDL_SCANCODE_UNKNOWN,       /*  196 */
-    SDL_SCANCODE_UNKNOWN,       /*  197 */
-    SDL_SCANCODE_UNKNOWN,       /*  198 */
-    SDL_SCANCODE_UNKNOWN,       /*  199 */
-    SDL_SCANCODE_UNKNOWN,       /*  KEY_PLAYCD      200 */
-    SDL_SCANCODE_UNKNOWN,       /*  KEY_PAUSECD     201 */
-    SDL_SCANCODE_UNKNOWN,       /*  KEY_PROG3       202 */
-    SDL_SCANCODE_UNKNOWN,       /*  KEY_PROG4       203 */
-    SDL_SCANCODE_UNKNOWN,       /*  KEY_DASHBOARD       204 AL Dashboard */
-    SDL_SCANCODE_UNKNOWN,       /*  KEY_SUSPEND     205 */
-    SDL_SCANCODE_UNKNOWN,       /*  KEY_CLOSE       206 AC Close */
-    SDL_SCANCODE_UNKNOWN,       /*  KEY_PLAY        207 */
-    SDL_SCANCODE_UNKNOWN,       /*  KEY_FASTFORWARD     208 */
-    SDL_SCANCODE_UNKNOWN,       /*  KEY_BASSBOOST       209 */
-    SDL_SCANCODE_UNKNOWN,       /*  KEY_PRINT       210 AC Print */
-    SDL_SCANCODE_UNKNOWN,       /*  KEY_HP          211 */
-    SDL_SCANCODE_UNKNOWN,       /*  KEY_CAMERA      212 */
-    SDL_SCANCODE_UNKNOWN,       /*  KEY_SOUND       213 */
-    SDL_SCANCODE_UNKNOWN,       /*  KEY_QUESTION        214 */
-    SDL_SCANCODE_UNKNOWN,       /*  KEY_EMAIL       215 */
-    SDL_SCANCODE_UNKNOWN,       /*  KEY_CHAT        216 */
-    SDL_SCANCODE_UNKNOWN,       /*  KEY_SEARCH      217 */
-    SDL_SCANCODE_UNKNOWN,       /*  KEY_CONNECT     218 */
-    SDL_SCANCODE_UNKNOWN,       /*  KEY_FINANCE     219 AL Checkbook/Finance */
-    SDL_SCANCODE_UNKNOWN,       /*  KEY_SPORT       220 */
-    SDL_SCANCODE_UNKNOWN,       /*  KEY_SHOP        221 */
-    SDL_SCANCODE_UNKNOWN,       /*  KEY_ALTERASE        222 */
-    SDL_SCANCODE_UNKNOWN,       /*  KEY_CANCEL      223 AC Cancel */
-    SDL_SCANCODE_UNKNOWN,       /*  KEY_BRIGHTNESSDOWN  224 */
-    SDL_SCANCODE_UNKNOWN,       /*  KEY_BRIGHTNESSUP    225 */
-    SDL_SCANCODE_UNKNOWN,       /*  KEY_MEDIA       226 */
-    SDL_SCANCODE_UNKNOWN,       /*  KEY_SWITCHVIDEOMODE 227 Cycle between available video outputs (Monitor/LCD/TV-out/etc) */
-    SDL_SCANCODE_UNKNOWN,       /*  KEY_KBDILLUMTOGGLE  228 */
-    SDL_SCANCODE_UNKNOWN,       /*  KEY_KBDILLUMDOWN    229 */
-    SDL_SCANCODE_UNKNOWN,       /*  KEY_KBDILLUMUP      230 */
-    SDL_SCANCODE_UNKNOWN,       /*  KEY_SEND        231 AC Send */
-    SDL_SCANCODE_UNKNOWN,       /*  KEY_REPLY       232 AC Reply */
-    SDL_SCANCODE_UNKNOWN,       /*  KEY_FORWARDMAIL     233 AC Forward Msg */
-    SDL_SCANCODE_UNKNOWN,       /*  KEY_SAVE        234 AC Save */
-    SDL_SCANCODE_UNKNOWN,       /*  KEY_DOCUMENTS       235 */
-    SDL_SCANCODE_UNKNOWN,       /*  KEY_BATTERY     236  */
-    SDL_SCANCODE_UNKNOWN,       /*  KEY_BLUETOOTH       237 */
-    SDL_SCANCODE_UNKNOWN,       /*  KEY_WLAN        238 */
-    SDL_SCANCODE_UNKNOWN,       /*  KEY_UWB         239 */
-    SDL_SCANCODE_UNKNOWN,       /*  KEY_UNKNOWN     240 */
-    SDL_SCANCODE_UNKNOWN,       /*  KEY_VIDEO_NEXT      241 drive next video source */
-    SDL_SCANCODE_UNKNOWN,       /*  KEY_VIDEO_PREV      242 drive previous video source */
-    SDL_SCANCODE_UNKNOWN,       /*  KEY_BRIGHTNESS_CYCLE    243 brightness up, after max is min */
-    SDL_SCANCODE_UNKNOWN,       /*  KEY_BRIGHTNESS_ZERO 244 brightness off, use ambient */
-    SDL_SCANCODE_UNKNOWN,       /*  KEY_DISPLAY_OFF     245 display device to off state */
-    SDL_SCANCODE_UNKNOWN,       /*  KEY_WIMAX       246 */
-    SDL_SCANCODE_UNKNOWN,       /*  KEY_RFKILL      247 Key that controls all radios */
-    SDL_SCANCODE_UNKNOWN,       /*  KEY_MICMUTE     248 Mute / unmute the microphone */
-};
-
 static Uint8 EVDEV_MouseButtons[] = {
     SDL_BUTTON_LEFT,            /*  BTN_LEFT        0x110 */
     SDL_BUTTON_RIGHT,           /*  BTN_RIGHT       0x111 */
@@ -342,134 +127,113 @@ static Uint8 EVDEV_MouseButtons[] = {
 };
 
 static const char* EVDEV_consoles[] = {
-    "/proc/self/fd/0",
+    /* "/proc/self/fd/0",
     "/dev/tty",
-    "/dev/tty0",
+    "/dev/tty0", */ /* the tty ioctl's prohibit these */
     "/dev/tty1",
     "/dev/tty2",
     "/dev/tty3",
     "/dev/tty4",
     "/dev/tty5",
     "/dev/tty6",
+    "/dev/tty7", /* usually X is spawned in tty7 */
     "/dev/vc/0",
     "/dev/console"
 };
 
-#define IS_CONSOLE(fd) isatty (fd) && ioctl(fd, KDGKBTYPE, &arg) == 0 && ((arg == KB_101) || (arg == KB_84))
-
-static int SDL_EVDEV_get_console_fd(void)
-{
-    int fd, i;
-    char arg = 0;
-    
-    /* Try a few consoles to see which one we have read access to */
-    
-    for(i = 0; i < SDL_arraysize(EVDEV_consoles); i++) {
-        fd = open(EVDEV_consoles[i], O_RDONLY);
-        if (fd >= 0) {
-            if (IS_CONSOLE(fd)) return fd;
-            close(fd);
-        }
-    }
-    
-    /* Try stdin, stdout, stderr */
+static int SDL_EVDEV_is_console( int fd ) {
+    int type;
     
-    for(fd = 0; fd < 3; fd++) {
-        if (IS_CONSOLE(fd)) return fd;
-    }
-    
-    /* We won't be able to send SDL_TEXTINPUT events */
-    return -1;
+    return isatty( fd ) && ioctl( fd, KDGKBTYPE, &type ) == 0 &&
+        ( type == KB_101 || type == KB_84 );
 }
 
 /* Prevent keystrokes from reaching the tty */
-static int SDL_EVDEV_mute_keyboard(int tty, int *kb_mode)
+static int SDL_EVDEV_mute_keyboard( int tty_fd, int* old_kb_mode )
 {
-    char arg;
+    if( !SDL_EVDEV_is_console( tty_fd ) ) {
+        return SDL_SetError( "Tried to mute an invalid tty" );
+    }
     
-    *kb_mode = 0; /* FIXME: Is this a sane default in case KDGKBMODE fails? */
-    if (!IS_CONSOLE(tty)) {
-        return SDL_SetError("Tried to mute an invalid tty");
+    if( ioctl( tty_fd, KDGKBMODE, old_kb_mode ) < 0 ) {
+        return SDL_SetError( "Failed to get keyboard mode during muting" );
     }
-    ioctl(tty, KDGKBMODE, kb_mode); /* It's not fatal if this fails */
-    if (ioctl(tty, KDSKBMUTE, 1) && ioctl(tty, KDSKBMODE, K_OFF)) {
-        return SDL_SetError("EVDEV: Failed muting keyboard");
+    
+    /* FIXME: atm this absolutely ruins the vt, and KDSKBMUTE isn't implemented
+       in the kernel */
+    /*
+    if( ioctl( tty_fd, KDSKBMODE, K_OFF ) < 0 ) {
+        return SDL_SetError( "Failed to set keyboard mode during muting" );
     }
+    */
     
     return 0;  
 }
 
 /* Restore the keyboard mode for given tty */
-static void SDL_EVDEV_unmute_keyboard(int tty, int kb_mode)
+static void SDL_EVDEV_unmute_keyboard( int tty_fd, int kb_mode )
 {
-    if (ioctl(tty, KDSKBMUTE, 0) && ioctl(tty, KDSKBMODE, kb_mode)) {
-        SDL_Log("EVDEV: Failed restoring keyboard mode");
+    /* read above */
+    /*
+    if( ioctl( tty_fd, KDSKBMODE, kb_mode ) < 0 ) {
+        SDL_Log( "Failed to unmute keyboard" );
     }
+    */
 }
 
-/* Read /sys/class/tty/tty0/active and open the tty */
 static int SDL_EVDEV_get_active_tty()
-{
-    int fd, len;
-    char ttyname[NAME_MAX + 1];
-    char ttypath[PATH_MAX+1] = "/dev/";
-    char arg;
+{  
+    int i, fd, ret, tty = 0;
+    char tiocl;
+    struct vt_stat vt_state;
+    char path[PATH_MAX + 1];
     
-    fd = open("/sys/class/tty/tty0/active", O_RDONLY);
-    if (fd < 0) {
-        return SDL_SetError("Could not determine which tty is active");
-    }
-    
-    len = read(fd, ttyname, NAME_MAX);
-    close(fd);
-    
-    if (len <= 0) {
-        return SDL_SetError("Could not read which tty is active");
-    }
-    
-    if (ttyname[len-1] == '\n') {
-        ttyname[len-1] = '\0';
-    }
-    else {
-        ttyname[len] = '\0';
-    }
-    
-    SDL_strlcat(ttypath, ttyname, PATH_MAX);
-    fd = open(ttypath, O_RDWR | O_NOCTTY);
-    if (fd < 0) {
-        return SDL_SetError("Could not open tty: %s", ttypath);
+    for( i = 0; i < SDL_arraysize( EVDEV_consoles ); i++ ) {
+        fd = open( EVDEV_consoles[i], O_RDONLY );
+        
+        if( fd < 0 && !SDL_EVDEV_is_console( fd ) )
+            break;
+        
+        tiocl = TIOCL_GETFGCONSOLE;
+        if( ( ret = ioctl( fd, TIOCLINUX, &tiocl ) ) >= 0 )
+            tty = ret + 1;
+        else if( ioctl( fd, VT_GETSTATE, &vt_state ) == 0 )
+            tty = vt_state.v_active;
+        
+        close( fd );
+        
+        if( tty ) {
+            sprintf( path, "/dev/tty%u", tty );
+            fd = open( path, O_RDONLY );
+            if( fd >= 0 && SDL_EVDEV_is_console( fd ) )
+                return fd;
+        }
     }
     
-    if (!IS_CONSOLE(fd)) {
-        close(fd);
-        return SDL_SetError("Invalid tty obtained: %s", ttypath);
-    }
-
-    return fd;  
+    return SDL_SetError( "Failed to determine active tty" );
 }
 
 int
 SDL_EVDEV_Init(void)
 {
-    int retval = 0;
-    
-    if (_this == NULL) {
-        
-        _this = (SDL_EVDEV_PrivateData *) SDL_calloc(1, sizeof(*_this));
-        if(_this == NULL) {
+    if( _this == NULL ) {
+        _this = (SDL_EVDEV_PrivateData*)SDL_calloc( 1, sizeof( *_this ) );
+        if( _this == NULL ) {
             return SDL_OutOfMemory();
         }
 
 #if SDL_USE_LIBUDEV
-        if (SDL_UDEV_Init() < 0) {
-            SDL_free(_this);
+        if( SDL_UDEV_Init() < 0 ) {
+            SDL_free( _this );
             _this = NULL;
             return -1;
         }
 
         /* Set up the udev callback */
         if (SDL_UDEV_AddCallback(SDL_EVDEV_udev_callback) < 0) {
-            SDL_EVDEV_Quit();
+            SDL_UDEV_Quit();
+            SDL_free( _this );
+            _this = NULL;
             return -1;
         }
         
@@ -479,109 +243,165 @@ SDL_EVDEV_Init(void)
         /* TODO: Scan the devices manually, like a caveman */
 #endif /* SDL_USE_LIBUDEV */
         
-        /* We need a physical terminal (not PTS) to be able to translate key code to symbols via the kernel tables */
-        _this->console_fd = SDL_EVDEV_get_console_fd();
+        /* We need a physical terminal (not PTS) to be able to translate key
+           code to symbols via the kernel tables */
+        _this->console_fd = SDL_EVDEV_get_active_tty();
         
-        /* Mute the keyboard so keystrokes only generate evdev events and do not leak through to the console */
-        _this->tty = STDIN_FILENO;
-        if (SDL_EVDEV_mute_keyboard(_this->tty, &_this->kb_mode) < 0) {
-            /* stdin is not a tty, probably we were launched remotely, so we try to disable the active tty */
-            _this->tty = SDL_EVDEV_get_active_tty();
-            if (_this->tty >= 0) {
-                if (SDL_EVDEV_mute_keyboard(_this->tty, &_this->kb_mode) < 0) {
-                    close(_this->tty);
-                    _this->tty = -1;
-                }
-            }
-        }
+        /* Mute the keyboard so keystrokes only generate evdev events and do not
+           leak through to the console */
+        SDL_EVDEV_mute_keyboard( _this->console_fd, &_this->kb_mode );
     }
     
     _this->ref_count += 1;
     
-    return retval;
+    return 0;
 }
 
 void
 SDL_EVDEV_Quit(void)
 {
-    if (_this == NULL) {
+    if( _this == NULL ) {
         return;
     }
     
     _this->ref_count -= 1;
     
-    if (_this->ref_count < 1) {
-        
+    if( _this->ref_count < 1 ) {
 #if SDL_USE_LIBUDEV
-        SDL_UDEV_DelCallback(SDL_EVDEV_udev_callback);
+        SDL_UDEV_DelCallback( SDL_EVDEV_udev_callback );
         SDL_UDEV_Quit();
 #endif /* SDL_USE_LIBUDEV */
        
-        if (_this->console_fd >= 0) {
-            close(_this->console_fd);
-        }
-        
-        if (_this->tty >= 0) {
-            SDL_EVDEV_unmute_keyboard(_this->tty, _this->kb_mode);
-            close(_this->tty);
+        if( _this->console_fd >= 0 ) {
+            SDL_EVDEV_unmute_keyboard( _this->console_fd, _this->kb_mode );
+            close( _this->console_fd );
         }
         
         /* Remove existing devices */
         while(_this->first != NULL) {
-            SDL_EVDEV_device_removed(_this->first->path);
+            SDL_EVDEV_device_removed( _this->first->path );
         }
         
-        SDL_assert(_this->first == NULL);
-        SDL_assert(_this->last == NULL);
-        SDL_assert(_this->numdevices == 0);
+        SDL_assert( _this->first == NULL );
+        SDL_assert( _this->last == NULL );
+        SDL_assert( _this->num_devices == 0 );
         
-        SDL_free(_this);
+        SDL_free( _this );
         _this = NULL;
     }
 }
 
 #if SDL_USE_LIBUDEV
-void SDL_EVDEV_udev_callback(SDL_UDEV_deviceevent udev_type, int udev_class, const char *devpath)
+void SDL_EVDEV_udev_callback( SDL_UDEV_deviceevent udev_event, int udev_class,
+    const char* dev_path )
 {
-    if (devpath == NULL) {
+    if( dev_path == NULL ) {
         return;
     }
     
-    switch(udev_type) {
+    switch( udev_event ) {
     case SDL_UDEV_DEVICEADDED:
-        if (!(udev_class & (SDL_UDEV_DEVICE_MOUSE|SDL_UDEV_DEVICE_KEYBOARD))) {
+        if( !( udev_class & ( SDL_UDEV_DEVICE_MOUSE | SDL_UDEV_DEVICE_KEYBOARD |
+            SDL_UDEV_DEVICE_TOUCHSCREEN ) ) )
             return;
-        }
-        SDL_EVDEV_device_added(devpath);
-        break;
-            
+
+        SDL_EVDEV_device_added( dev_path, udev_class );
+        break;  
     case SDL_UDEV_DEVICEREMOVED:
-        SDL_EVDEV_device_removed(devpath);
+        SDL_EVDEV_device_removed( dev_path );
         break;
-            
     default:
         break;
     }
 }
-
 #endif /* SDL_USE_LIBUDEV */
 
+#ifdef SDL_INPUT_LINUXKD
+/* this logic is pulled from kbd_keycode() in drivers/tty/vt/keyboard.c in the
+   Linux kernel source */
+static void SDL_EVDEV_do_text_input( unsigned short keycode ) {
+    char shift_state;
+    int locks_state;
+    struct kbentry kbe;
+    unsigned char type;
+    char text[2] = { 0 };
+    
+    if( _this->console_fd < 0 )
+        return;
+    
+    shift_state = TIOCL_GETSHIFTSTATE;
+    if( ioctl( _this->console_fd, TIOCLINUX, &shift_state ) < 0 ) {
+        /* TODO: error */
+        return;
+    }
+
+    kbe.kb_table = shift_state;
+    kbe.kb_index = keycode;
+    
+    if( ioctl( _this->console_fd, KDGKBENT, &kbe ) < 0 ) {
+        /* TODO: error */
+        return;
+    }
+    
+    type = KTYP( kbe.kb_value );
+    
+    if( type < 0xf0 ) {
+        /* 
+         * FIXME: keysyms with a type below 0xf0 represent a unicode character
+         * which requires special handling due to dead characters, diacritics,
+         * etc. For perfect input a proper way to deal with such characters
+         * should be implemented.
+         *
+         * For reference, the only place I was able to find out about this
+         * special 0xf0 value was in an unused? couple of patches listed below.
+         *
+         * http://ftp.tc.edu.tw/pub/docs/Unicode/utf8/linux-2.3.12-keyboard.diff
+         * http://ftp.tc.edu.tw/pub/docs/Unicode/utf8/linux-2.3.12-console.diff
+         */
+        
+        return;
+    }
+    
+    type -= 0xf0;
+    
+    /* if type is KT_LETTER then it can be affected by Caps Lock */
+    if( type == KT_LETTER ) {
+        type = KT_LATIN;
+    
+        if( ioctl( _this->console_fd, KDGKBLED, &locks_state ) < 0 ) {
+            /* TODO: error */
+            return;
+        }
+        
+        if( locks_state & K_CAPSLOCK ) {
+            kbe.kb_table = shift_state ^ ( 1 << KG_SHIFT );
+            
+            if( ioctl( _this->console_fd, KDGKBENT, &kbe ) < 0 ) {
+                /* TODO: error */
+                return;
+            }
+        }
+    }
+    
+    /* TODO: convert values >= 0x80 from ISO-8859-1? to UTF-8 */
+    if( type != KT_LATIN || KVAL( kbe.kb_value ) >= 0x80 )
+        return;
+    
+    *text = KVAL( kbe.kb_value );
+    SDL_SendKeyboardText( text );
+}
+#endif /* SDL_INPUT_LINUXKD */
+
 void 
 SDL_EVDEV_Poll(void)
 {
     struct input_event events[32];
-    int i, len;
+    int i, j, len;
     SDL_evdevlist_item *item;
     SDL_Scancode scan_code;
     int mouse_button;
     SDL_Mouse *mouse;
-#ifdef SDL_INPUT_LINUXKD
-    Uint16 modstate;
-    struct kbentry kbe;
-    static char keysym[8];
-    char *end;
-    Uint32 kval;
-#endif
+    float norm_x, norm_y;
 
     if (!_this) {
         return;
@@ -597,6 +417,13 @@ SDL_EVDEV_Poll(void)
         while ((len = read(item->fd, events, (sizeof events))) > 0) {
             len /= sizeof(events[0]);
             for (i = 0; i < len; ++i) {
+                /* special handling for touchscreen, that should eventually be
+                   used for all devices */
+                if( item->out_of_sync && item->is_touchscreen &&
+                    events[i].type == EV_SYN && events[i].code != SYN_REPORT ) {
+                    break;
+                }
+                
                 switch (events[i].type) {
                 case EV_KEY:
                     if (events[i].code >= BTN_MOUSE && events[i].code < BTN_MOUSE + SDL_arraysize(EVDEV_MouseButtons)) {
@@ -614,57 +441,55 @@ SDL_EVDEV_Poll(void)
                     if (scan_code != SDL_SCANCODE_UNKNOWN) {
                         if (events[i].value == 0) {
                             SDL_SendKeyboardKey(SDL_RELEASED, scan_code);
-                        } else if (events[i].value == 1 || events[i].value == 2 /* Key repeated */) {
+                        } else if( events[i].value == 1 || events[i].value == 2 /* key repeated */ ) {
                             SDL_SendKeyboardKey(SDL_PRESSED, scan_code);
 #ifdef SDL_INPUT_LINUXKD
-                            if (_this->console_fd >= 0) {
-                                kbe.kb_index = events[i].code;
-                                /* Convert the key to an UTF-8 char */
-                                /* Ref: http://www.linuxjournal.com/article/2783 */
-                                modstate = SDL_GetModState();
-                                kbe.kb_table = 0;
-                                
-                                /* Ref: http://graphics.stanford.edu/~seander/bithacks.html#ConditionalSetOrClearBitsWithoutBranching */
-                                kbe.kb_table |= -((modstate & KMOD_LCTRL) != 0) & (1 << KG_CTRLL | 1 << KG_CTRL);
-                                kbe.kb_table |= -((modstate & KMOD_RCTRL) != 0) & (1 << KG_CTRLR | 1 << KG_CTRL);
-                                kbe.kb_table |= -((modstate & KMOD_LSHIFT) != 0) & (1 << KG_SHIFTL | 1 << KG_SHIFT);
-                                kbe.kb_table |= -((modstate & KMOD_RSHIFT) != 0) & (1 << KG_SHIFTR | 1 << KG_SHIFT);
-                                kbe.kb_table |= -((modstate & KMOD_LALT) != 0) & (1 << KG_ALT);
-                                kbe.kb_table |= -((modstate & KMOD_RALT) != 0) & (1 << KG_ALTGR);
-
-                                if (ioctl(_this->console_fd, KDGKBENT, (unsigned long)&kbe) == 0 && 
-                                    ((KTYP(kbe.kb_value) == KT_LATIN) || (KTYP(kbe.kb_value) == KT_ASCII) || (KTYP(kbe.kb_value) == KT_LETTER))) 
-                                {
-                                    kval = KVAL(kbe.kb_value);
-                                    
-                                    /* While there's a KG_CAPSSHIFT symbol, it's not useful to build the table index with it
-                                     * because 1 << KG_CAPSSHIFT overflows the 8 bits of kb_table 
-                                     * So, we do the CAPS LOCK logic here. Note that isalpha depends on the locale!
-                                     */
-                                    if (modstate & KMOD_CAPS && isalpha(kval)) {
-                                        if (isupper(kval)) {
-                                            kval = tolower(kval);
-                                        } else {
-                                            kval = toupper(kval);
-                                        }
-                                    }
-                                     
-                                    /* Convert to UTF-8 and send */
-                                    end = SDL_UCS4ToUTF8(kval, keysym);
-                                    *end = '\0';
-                                    SDL_SendKeyboardText(keysym);
-                                }
-                            }
+                            SDL_EVDEV_do_text_input( events[i].code );
 #endif /* SDL_INPUT_LINUXKD */
                         }
                     }
                     break;
                 case EV_ABS:
                     switch(events[i].code) {
+                    case ABS_MT_SLOT:
+                        if( !item->is_touchscreen ) /* FIXME: temp hack */
+                            break;
+                        item->touchscreen_data->current_slot = events[i].value;
+                        break;
+                    case ABS_MT_TRACKING_ID:
+                        if( !item->is_touchscreen ) /* FIXME: temp hack */
+                            break;
+                        if( events[i].value >= 0 ) {
+                            item->touchscreen_data->slots[item->touchscreen_data->current_slot].tracking_id = events[i].value;
+                            item->touchscreen_data->slots[item->touchscreen_data->current_slot].delta = EVDEV_TOUCH_SLOTDELTA_DOWN;
+                        } else {
+                            item->touchscreen_data->slots[item->touchscreen_data->current_slot].delta = EVDEV_TOUCH_SLOTDELTA_UP;
+                        }
+                        break;
+                    case ABS_MT_POSITION_X:
+                        if( !item->is_touchscreen ) /* FIXME: temp hack */
+                            break;
+                        item->touchscreen_data->slots[item->touchscreen_data->current_slot].x = events[i].value;
+                        if( item->touchscreen_data->slots[item->touchscreen_data->current_slot].delta == EVDEV_TOUCH_SLOTDELTA_NONE ) {
+                            item->touchscreen_data->slots[item->touchscreen_data->current_slot].delta = EVDEV_TOUCH_SLOTDELTA_MOVE;
+                        }
+                        break;
+                    case ABS_MT_POSITION_Y:
+                        if( !item->is_touchscreen ) /* FIXME: temp hack */
+                            break;
+                        item->touchscreen_data->slots[item->touchscreen_data->current_slot].y = events[i].value;
+                        if( item->touchscreen_data->slots[item->touchscreen_data->current_slot].delta == EVDEV_TOUCH_SLOTDELTA_NONE ) {
+                            item->touchscreen_data->slots[item->touchscreen_data->current_slot].delta = EVDEV_TOUCH_SLOTDELTA_MOVE;
+                        }
+                        break;
                     case ABS_X:
+                        if( item->is_touchscreen ) /* FIXME: temp hack */
+                            break;
                         SDL_SendMouseMotion(mouse->focus, mouse->mouseID, SDL_FALSE, events[i].value, mouse->y);
                         break;
                     case ABS_Y:
+                        if( item->is_touchscreen ) /* FIXME: temp hack */
+                            break;
                         SDL_SendMouseMotion(mouse->focus, mouse->mouseID, SDL_FALSE, mouse->x, events[i].value);
                         break;
                     default:
@@ -691,7 +516,41 @@ SDL_EVDEV_Poll(void)
                     break;
                 case EV_SYN:
                     switch (events[i].code) {
+                    case SYN_REPORT:
+                        if( !item->is_touchscreen ) /* FIXME: temp hack */
+                            break;
+                            
+                        for( j = 0; j < item->touchscreen_data->max_slots; j++ ) {
+                            norm_x = (float)(item->touchscreen_data->slots[j].x - item->touchscreen_data->min_x) /
+                                (float)item->touchscreen_data->range_x;
+                            norm_y = (float)(item->touchscreen_data->slots[j].y - item->touchscreen_data->min_y) /
+                                (float)item->touchscreen_data->range_y;
+                        
+                            switch( item->touchscreen_data->slots[j].delta ) {
+                            case EVDEV_TOUCH_SLOTDELTA_DOWN:
+                                SDL_SendTouch( item->fd, item->touchscreen_data->slots[j].tracking_id, SDL_TRUE, norm_x, norm_y, 1.0f );
+                                item->touchscreen_data->slots[j].delta = EVDEV_TOUCH_SLOTDELTA_NONE;
+                                break;
+                            case EVDEV_TOUCH_SLOTDELTA_UP:
+                                SDL_SendTouch( item->fd, item->touchscreen_data->slots[j].tracking_id, SDL_FALSE, norm_x, norm_y, 1.0f );
+                                item->touchscreen_data->slots[j].tracking_id = -1;
+                                item->touchscreen_data->slots[j].delta = EVDEV_TOUCH_SLOTDELTA_NONE;
+                                break;
+                            case EVDEV_TOUCH_SLOTDELTA_MOVE:
+                                SDL_SendTouchMotion( item->fd, item->touchscreen_data->slots[j].tracking_id, norm_x, norm_y, 1.0f );
+                                item->touchscreen_data->slots[j].delta = EVDEV_TOUCH_SLOTDELTA_NONE;
+                                break;
+                            default:
+                                break;
+                            }
+                        }
+                        
+                        if( item->out_of_sync )
+                            item->out_of_sync = 0;
+                        break;
                     case SYN_DROPPED:
+                        if( item->is_touchscreen )
+                            item->out_of_sync = 1;
                         SDL_EVDEV_sync_device(item);
                         break;
                     default:
@@ -705,34 +564,230 @@ SDL_EVDEV_Poll(void)
 }
 
 static SDL_Scancode
-SDL_EVDEV_translate_keycode(int keycode)
+SDL_EVDEV_translate_keycode( int keycode )
 {
     SDL_Scancode scancode = SDL_SCANCODE_UNKNOWN;
 
-    if (keycode < SDL_arraysize(EVDEV_Keycodes)) {
-        scancode = EVDEV_Keycodes[keycode];
-    }
-    if (scancode == SDL_SCANCODE_UNKNOWN) {
-        SDL_Log("The key you just pressed is not recognized by SDL. To help get this fixed, please report this to the SDL mailing list <sdl@libsdl.org> EVDEV KeyCode %d \n", keycode);
+    if( keycode < SDL_arraysize( linux_scancode_table ) )
+        scancode = linux_scancode_table[keycode];
+
+    if( scancode == SDL_SCANCODE_UNKNOWN ) {
+        SDL_Log( "The key you just pressed is not recognized by SDL. To help "
+            "get this fixed, please report this to the SDL mailing list "
+            "<sdl@libsdl.org> EVDEV KeyCode %d\n", keycode );
     }
+
     return scancode;
 }
 
+static int
+SDL_EVDEV_init_touchscreen( SDL_evdevlist_item* item ) {
+    int ret, i;
+    char name[64];
+    struct input_absinfo abs_info;
+    
+    if( !item->is_touchscreen )
+        return 0;
+    
+    item->touchscreen_data = SDL_calloc( 1, sizeof( *item->touchscreen_data ) );
+    if( item->touchscreen_data == NULL )
+        return SDL_OutOfMemory();
+    
+    ret = ioctl( item->fd, EVIOCGNAME( sizeof( name ) ), name );
+    if( ret < 0 ) {
+        SDL_free( item->touchscreen_data );
+        return SDL_SetError( "Failed to get evdev touchscreen name" );
+    }
+    
+    item->touchscreen_data->name = SDL_strdup( name );
+    if( item->touchscreen_data->name == NULL ) {
+        SDL_free( item->touchscreen_data );
+        return SDL_OutOfMemory();
+    }
+    
+    ret = ioctl( item->fd, EVIOCGABS( ABS_MT_POSITION_X ), &abs_info );
+    if( ret < 0 ) {
+        SDL_free( item->touchscreen_data->name );
+        SDL_free( item->touchscreen_data );
+        return SDL_SetError( "Failed to get evdev touchscreen limits" );
+    }
+    item->touchscreen_data->min_x = abs_info.minimum;
+    item->touchscreen_data->max_x = abs_info.maximum;
+    item->touchscreen_data->range_x = abs_info.maximum - abs_info.minimum;
+        
+    ret = ioctl( item->fd, EVIOCGABS( ABS_MT_POSITION_Y ), &abs_info );
+    if( ret < 0 ) {
+        SDL_free( item->touchscreen_data->name );
+        SDL_free( item->touchscreen_data );
+        return SDL_SetError( "Failed to get evdev touchscreen limits" );
+    }
+    item->touchscreen_data->min_y = abs_info.minimum;
+    item->touchscreen_data->max_y = abs_info.maximum;
+    item->touchscreen_data->range_y = abs_info.maximum - abs_info.minimum;
+    
+    ret = ioctl( item->fd, EVIOCGABS( ABS_MT_SLOT ), &abs_info );
+    if( ret < 0 ) {
+        SDL_free( item->touchscreen_data->name );
+        SDL_free( item->touchscreen_data );
+        return SDL_SetError( "Failed to get evdev touchscreen limits" );
+    }
+    item->touchscreen_data->max_slots = abs_info.maximum + 1;
+    
+    item->touchscreen_data->slots = SDL_calloc(
+        item->touchscreen_data->max_slots,
+        sizeof( *item->touchscreen_data->slots ) );
+    if( item->touchscreen_data->slots == NULL ) {
+        SDL_free( item->touchscreen_data->name );
+        SDL_free( item->touchscreen_data );
+        return SDL_OutOfMemory();
+    }
+    
+    for( i = 0; i < item->touchscreen_data->max_slots; i++ ) {
+        item->touchscreen_data->slots[i].tracking_id = -1;
+    }
+    
+    ret = SDL_AddTouch( item->fd, /* I guess our fd is unique enough */
+        item->touchscreen_data->name );
+    if( ret < 0 ) {
+        SDL_free( item->touchscreen_data->slots );
+        SDL_free( item->touchscreen_data->name );
+        SDL_free( item->touchscreen_data );
+        return ret;
+    }
+    
+    return 0;
+}
+
+static void
+SDL_EVDEV_destroy_touchscreen( SDL_evdevlist_item* item ) {
+    if( !item->is_touchscreen )
+        return;
+    
+    SDL_DelTouch( item->fd );
+    SDL_free( item->touchscreen_data->slots );
+    SDL_free( item->touchscreen_data->name );
+    SDL_free( item->touchscreen_data );
+}
+
 static void
 SDL_EVDEV_sync_device(SDL_evdevlist_item *item) 
 {
-    /* TODO: get full state of device and report whatever is required */
+    int i, ret;
+    struct input_absinfo abs_info;
+    /*
+     * struct input_mt_request_layout {
+     *     __u32 code;
+     *     __s32 values[num_slots];
+     * };
+     *
+     * this is the structure we're trying to emulate
+     */
+    __u32* mt_req_code;
+    __s32* mt_req_values;
+    size_t mt_req_size;
+    
+    /* TODO: sync devices other than touchscreen */
+    if( !item->is_touchscreen )
+        return;
+    
+    mt_req_size = sizeof( *mt_req_code ) +
+        sizeof( *mt_req_values ) * item->touchscreen_data->max_slots;
+    
+    mt_req_code = SDL_calloc( 1, mt_req_size );
+    if( mt_req_code == NULL ) {
+        SDL_Log( "Failed to sync device" );
+        return;
+    }
+    
+    mt_req_values = (__s32*)mt_req_code + 1;
+    
+    *mt_req_code = ABS_MT_TRACKING_ID;
+    ret = ioctl( item->fd, EVIOCGMTSLOTS( mt_req_size ), mt_req_code );
+    if( ret < 0 ) {
+        SDL_free( mt_req_code );
+        SDL_Log( "Failed to sync device" );
+        return;
+    }
+    for( i = 0; i < item->touchscreen_data->max_slots; i++ ) {
+        /*
+         * This doesn't account for the very edge case of the user removing their
+         * finger and replacing it on the screen during the time we're out of sync,
+         * which'll mean that we're not going from down -> up or up -> down, we're
+         * going from down -> down but with a different tracking id, meaning we'd
+         * have to tell SDL of the two events, but since we wait till SYN_REPORT in
+         * SDL_EVDEV_Poll to tell SDL, the current structure of this code doesn't
+         * allow it. Lets just pray to God it doesn't happen.
+         */
+        if( item->touchscreen_data->slots[i].tracking_id < 0 &&
+            mt_req_values[i] >= 0 ) {
+            item->touchscreen_data->slots[i].tracking_id = mt_req_values[i];
+            item->touchscreen_data->slots[i].delta = EVDEV_TOUCH_SLOTDELTA_DOWN;
+        } else if( item->touchscreen_data->slots[i].tracking_id >= 0 &&
+            mt_req_values[i] < 0 ) {
+            item->touchscreen_data->slots[i].tracking_id = -1;
+            item->touchscreen_data->slots[i].delta = EVDEV_TOUCH_SLOTDELTA_UP;
+        }
+    }
+    
+    *mt_req_code = ABS_MT_POSITION_X;
+    ret = ioctl( item->fd, EVIOCGMTSLOTS( mt_req_size ), mt_req_code );
+    if( ret < 0 ) {
+        SDL_free( mt_req_code );
+        SDL_Log( "Failed to sync device" );
+        return;
+    }
+    for( i = 0; i < item->touchscreen_data->max_slots; i++ ) {
+        if( item->touchscreen_data->slots[i].tracking_id >= 0 &&
+            item->touchscreen_data->slots[i].x != mt_req_values[i] ) {
+            item->touchscreen_data->slots[i].x = mt_req_values[i];
+            if( item->touchscreen_data->slots[i].delta ==
+                EVDEV_TOUCH_SLOTDELTA_NONE ) {
+                item->touchscreen_data->slots[i].delta =
+                    EVDEV_TOUCH_SLOTDELTA_MOVE;
+            }
+        }
+    }
+    
+    *mt_req_code = ABS_MT_POSITION_Y;
+    ret = ioctl( item->fd, EVIOCGMTSLOTS( mt_req_size ), mt_req_code );
+    if( ret < 0 ) {
+        SDL_free( mt_req_code );
+        SDL_Log( "Failed to sync device" );
+        return;
+    }
+    for( i = 0; i < item->touchscreen_data->max_slots; i++ ) {
+        if( item->touchscreen_data->slots[i].tracking_id >= 0 &&
+            item->touchscreen_data->slots[i].y != mt_req_values[i] ) {
+            item->touchscreen_data->slots[i].y = mt_req_values[i];
+            if( item->touchscreen_data->slots[i].delta ==
+                EVDEV_TOUCH_SLOTDELTA_NONE ) {
+                item->touchscreen_data->slots[i].delta =
+                    EVDEV_TOUCH_SLOTDELTA_MOVE;
+            }
+        }
+    }
+    
+    ret = ioctl( item->fd, EVIOCGABS( ABS_MT_SLOT ), &abs_info );
+    if( ret < 0 ) {
+        SDL_free( mt_req_code );
+        SDL_Log( "Failed to sync device" );
+        return;
+    }
+    item->touchscreen_data->current_slot = abs_info.value;
+    
+    SDL_free( mt_req_code );
 }
 
 #if SDL_USE_LIBUDEV
 static int
-SDL_EVDEV_device_added(const char *devpath)
+SDL_EVDEV_device_added(const char *dev_path, int udev_class)
 {
+    int ret;
     SDL_evdevlist_item *item;
 
     /* Check to make sure it's not already in list. */
     for (item = _this->first; item != NULL; item = item->next) {
-        if (SDL_strcmp(devpath, item->path) == 0) {
+        if (SDL_strcmp(dev_path, item->path) == 0) {
             return -1;  /* already have this one */
         }
     }
@@ -742,21 +797,28 @@ SDL_EVDEV_device_added(const char *devpath)
         return SDL_OutOfMemory();
     }
 
-    item->fd = open(devpath, O_RDONLY, 0);
+    item->fd = open( dev_path, O_RDONLY | O_NONBLOCK );
     if (item->fd < 0) {
         SDL_free(item);
-        return SDL_SetError("Unable to open %s", devpath);
+        return SDL_SetError("Unable to open %s", dev_path);
     }
     
-    item->path = SDL_strdup(devpath);
+    item->path = SDL_strdup(dev_path);
     if (item->path == NULL) {
         close(item->fd);
         SDL_free(item);
         return SDL_OutOfMemory();
     }
     
-    /* Non blocking read mode */
-    fcntl(item->fd, F_SETFL, O_NONBLOCK);
+    if( udev_class & SDL_UDEV_DEVICE_TOUCHSCREEN ) {
+        item->is_touchscreen = 1;
+        
+        if( ( ret = SDL_EVDEV_init_touchscreen( item ) ) < 0 ) {
+            close(item->fd);
+            SDL_free(item);
+            return ret;
+        }
+    }
     
     if (_this->last == NULL) {
         _this->first = _this->last = item;
@@ -767,19 +829,19 @@ SDL_EVDEV_device_added(const char *devpath)
     
     SDL_EVDEV_sync_device(item);
     
-    return _this->numdevices++;
+    return _this->num_devices++;
 }
 #endif /* SDL_USE_LIBUDEV */
 
 static int
-SDL_EVDEV_device_removed(const char *devpath)
+SDL_EVDEV_device_removed(const char *dev_path)
 {
     SDL_evdevlist_item *item;
     SDL_evdevlist_item *prev = NULL;
 
     for (item = _this->first; item != NULL; item = item->next) {
         /* found it, remove it. */
-        if (SDL_strcmp(devpath, item->path) == 0) {
+        if (SDL_strcmp(dev_path, item->path) == 0) {
             if (prev != NULL) {
                 prev->next = item->next;
             } else {
@@ -789,10 +851,13 @@ SDL_EVDEV_device_removed(const char *devpath)
             if (item == _this->last) {
                 _this->last = prev;
             }
+            if( item->is_touchscreen ) {
+                SDL_EVDEV_destroy_touchscreen( item );
+            }
             close(item->fd);
             SDL_free(item->path);
             SDL_free(item);
-            _this->numdevices--;
+            _this->num_devices--;
             return 0;
         }
         prev = item;
@@ -805,4 +870,3 @@ SDL_EVDEV_device_removed(const char *devpath)
 #endif /* SDL_INPUT_LINUXEV */
 
 /* vi: set ts=4 sw=4 expandtab: */
-

src/core/linux/SDL_evdev.h

@@ -27,31 +27,11 @@
 #ifdef SDL_INPUT_LINUXEV
 
 #include "SDL_events.h"
-#include <sys/stat.h>
-
-typedef struct SDL_evdevlist_item
-{
-    char *path;
-    int fd;
-    struct SDL_evdevlist_item *next;
-} SDL_evdevlist_item;
-
-typedef struct SDL_EVDEV_PrivateData
-{
-    SDL_evdevlist_item *first;
-    SDL_evdevlist_item *last;
-    int numdevices;
-    int ref_count;
-    int console_fd;
-    int kb_mode;
-    int tty;
-} SDL_EVDEV_PrivateData;
 
 extern int SDL_EVDEV_Init(void);
 extern void SDL_EVDEV_Quit(void);
 extern void SDL_EVDEV_Poll(void);
 
-
 #endif /* SDL_INPUT_LINUXEV */
 
 #endif /* _SDL_evdev_h */

src/core/linux/SDL_udev.c

@@ -349,7 +349,9 @@ guess_device_class(struct udev_device *dev)
         } else if (test_bit(BTN_MOUSE, bitmask_key)) {
             devclass |= SDL_UDEV_DEVICE_MOUSE; /* ID_INPUT_MOUSE */
         } else if (test_bit(BTN_TOUCH, bitmask_key)) {
-            ; /* ID_INPUT_TOUCHSCREEN */
+            /* TODO: better determining between touchscreen and multitouch touchpad,
+               see https://github.com/systemd/systemd/blob/master/src/udev/udev-builtin-input_id.c */
+            devclass |= SDL_UDEV_DEVICE_TOUCHSCREEN; /* ID_INPUT_TOUCHSCREEN */
         }
 
         if (test_bit(BTN_TRIGGER, bitmask_key) ||
@@ -411,6 +413,11 @@ device_event(SDL_UDEV_deviceevent type, struct udev_device *dev)
         if (val != NULL && SDL_strcmp(val, "1") == 0 ) {
             devclass |= SDL_UDEV_DEVICE_MOUSE;
         }
+        
+        val = _this->udev_device_get_property_value(dev, "ID_INPUT_TOUCHSCREEN");
+        if (val != NULL && SDL_strcmp(val, "1") == 0 ) {
+            devclass |= SDL_UDEV_DEVICE_TOUCHSCREEN;
+        }
 
         /* The undocumented rule is:
            - All devices with keys get ID_INPUT_KEY

src/core/linux/SDL_udev.h

@@ -42,17 +42,19 @@
 
 typedef enum
 {
-    SDL_UDEV_DEVICEADDED = 0x0001,
+    SDL_UDEV_DEVICEADDED = 1,
     SDL_UDEV_DEVICEREMOVED
 } SDL_UDEV_deviceevent;
 
 /* A device can be any combination of these classes */
 typedef enum
 {
+    SDL_UDEV_DEVICE_UNKNOWN     = 0x0000,
     SDL_UDEV_DEVICE_MOUSE       = 0x0001,
     SDL_UDEV_DEVICE_KEYBOARD    = 0x0002,
     SDL_UDEV_DEVICE_JOYSTICK    = 0x0004,
-    SDL_UDEV_DEVICE_SOUND       = 0x0008
+    SDL_UDEV_DEVICE_SOUND       = 0x0008,
+    SDL_UDEV_DEVICE_TOUCHSCREEN = 0x0010
 } SDL_UDEV_deviceclass;
 
 typedef void (*SDL_UDEV_Callback)(SDL_UDEV_deviceevent udev_type, int udev_class, const char *devpath);