added an extra key column (alt now on keyboard by default), added cyrillic keymap, added a toggle to enable/disable overlays, added quick toggle buttons to toggle primary two layers. Added some configurability using command line parameters and environment variables.

README

@@ -1,5 +1,6 @@
 SVKBD
 =====
+
 This is a simple virtual keyboard, intended to be used in environments,
 where no keyboard is available.
 
@@ -9,8 +10,11 @@ Installation
 	$ make
 	$ make install
 
-This will create by default `svkbd-en`, which is svkbd using an English
+This will create by default `svkbd-sxmo`, which is svkbd using an versatile
-keyboard layout. You can create svkbd for additional layouts by doing:
+layout with multiple layers and overlays, and optimised for mobile devices.
+It was designed for [Simple X Mobile](https://sr.ht/~mil/Sxmo).
+
+You can create svkbd for additional layouts by doing:
 
 	$ make LAYOUT=$layout
 
@@ -20,25 +24,36 @@ This will take the file `layout.$layout.h` and create `svkbd-$layout`.
 Usage
 -----
 
-	$ svkbd-en
+	% svkbd-sxmo
 
 This will open svkbd at the bottom of the screen, showing the default
 English layout.
 
-	$ svkbd-en -d
+	% svkbd-sxmo -d
 
-This tells svkbd-en to announce itself being a dock window, which then
+This tells svkbd-sxmo to announce itself being a dock window, which then
 is managed differently between different window managers. If using dwm
 and the dock patch, then this will make svkbd being managed by dwm and
 some space of the screen being reserved for it.
 
-	$ svkbd-en -g 400x200+1+1
+	% svkbd-sxmo -g 400x200+1+1
 
 This will start svkbd-en with a size of 400x200 and at the upper left
 window corner.
 
+You can enable layers on the fly through either the ``-l`` flag or through the ``SVKBD_LAYERS`` environment variable.
+They both take a comma separated list of layer names (as defined in your ``layout.*.h``). Use the ``↺`` button in the
+bottom-left to cycle through all the layers.
+
+The virtual keyboard comes with overlays that will show when certain keys are hold pressed for a longer time. For
+example, a long press on the ``a`` key will enable an overview showing all kinds of diacritic combinations for ``a``.
+
+Overlay functionality interferes with the ability to hold a key and have it outputted repeatedly.  You can disable
+overlay functionality with the ``-O`` flag or by setting the environment variable ``SVKBD_ENABLEOVERLAYS=0``. There is
+also a key on the function layer of the keyboard itself to enable/disable this behaviour on the fly. Its label shows
+``≅`` when the overlay functionality is enabled and ``≇`` when not.
+
 Repository
 ----------
 
-	git clone https://git.suckless.org/svkbd
+	git clone http://git.suckless.org/svkbd
-

layout.sxmo.h

@@ -1,7 +1,8 @@
-#define KEYS 40
+#define KEYS 43
 static Key keys[KEYS] = { NULL };
 
 static Key keys_en[KEYS] = {
+        { "Esc", XK_Escape, 1 },
         { 0, XK_q, 1 },
         { 0, XK_w, 1 },
         { 0, XK_e, 1 },
@@ -15,6 +16,7 @@ static Key keys_en[KEYS] = {
 
         { 0 }, /* New row */
 
+        { "'\"", XK_apostrophe, 1 },
         { 0, XK_a, 1 },
         { 0, XK_s, 1 },
         { 0, XK_d, 1 },
@@ -25,10 +27,10 @@ static Key keys_en[KEYS] = {
         { 0, XK_k, 1 },
         { 0, XK_l, 1 },
         { "/?", XK_slash, 1 },
-        /*{ "'", XK_apostrophe, 2 },*/
 
         { 0 }, /* New row */
 
+        { "123", XK_Mode_switch, 1 },
         { 0, XK_z, 1 },
         { 0, XK_x, 1 },
         { 0, XK_c, 1 },
@@ -36,25 +38,21 @@ static Key keys_en[KEYS] = {
         { 0, XK_b, 1 },
         { 0, XK_n, 1 },
         { 0, XK_m, 1 },
-        /*{ "/?", XK_slash, 1 },*/
         { "Tab", XK_Tab, 1 },
         { "⌫Bksp", XK_BackSpace, 2 },
 
         { 0 }, /* New row */
         { "↺", XK_Cancel, 1},
-        { "Shft", XK_Shift_L, 1 },
+        { "Shift", XK_Shift_L, 2 },
-        /*{ "L", XK_Left, 1 },*/
+        { "Ctrl", XK_Control_L, 1 },
+        { "Alt", XK_Alt_L, 1 },
+        { "", XK_space, 2 },
         { "↓", XK_Down, 1 },
         { "↑", XK_Up, 1 },
-        /*{ "R", XK_Right, 1 },*/
-        { "", XK_space, 2 },
-        { "Esc", XK_Escape, 1 },
-        { "Ctrl", XK_Control_L, 1 },
-        /*{ "Alt", XK_Alt_L, 1 },*/
         { "↲ Enter", XK_Return, 2 },
 };
 
-#define OVERLAYS 165
+#define OVERLAYS 197
 static Key overlay[OVERLAYS] = {
         { 0, XK_a }, //Overlay for a
         //---
@@ -195,6 +193,58 @@ static Key overlay[OVERLAYS] = {
         { 0, XK_r }, //New overlay
         //---
         { "ř", XK_rcaron },
+        { 0, XK_Cancel }, /* XK_Cancel signifies  overlay boundary */
+        //---
+        { 0, XK_Cyrillic_softsign }, //New overlay
+        //---
+        { "ъ", XK_Cyrillic_hardsign },
+        { 0, XK_Cancel }, /* XK_Cancel signifies  overlay boundary */
+        //---
+        { 0, XK_Cyrillic_ie }, //New overlay
+        //---
+        { "ё", XK_Cyrillic_io },
+        { 0, XK_Cancel }, /* XK_Cancel signifies  overlay boundary */
+        //---
+        { 0, XK_Cyrillic_e }, //New overlay
+        //---
+        { "Є", XK_Ukrainian_ie },
+        { 0, XK_Cancel }, /* XK_Cancel signifies  overlay boundary */
+        //---
+        { 0, XK_Cyrillic_i }, //New overlay
+        //---
+        { "і", XK_Ukrainian_i },
+        { "ї", XK_Ukrainian_yi },
+        { 0, XK_Cancel }, /* XK_Cancel signifies  overlay boundary */
+        //---
+        { 0, XK_Cyrillic_u }, //New overlay
+        //---
+        { "ў", XK_Byelorussian_shortu },
+        { 0, XK_Cancel }, /* XK_Cancel signifies  overlay boundary */
+		//---
+        { 0, XK_Cyrillic_shorti }, //New overlay
+        //---
+        { "ј", XK_Cyrillic_je },
+        { 0, XK_Cancel }, /* XK_Cancel signifies  overlay boundary */
+		//---
+        { 0, XK_Cyrillic_el }, //New overlay
+        //---
+        { "љ", XK_Cyrillic_lje },
+        { 0, XK_Cancel }, /* XK_Cancel signifies  overlay boundary */
+		//---
+        { 0, XK_Cyrillic_en }, //New overlay
+        //---
+        { "њ", XK_Cyrillic_nje },
+        { 0, XK_Cancel }, /* XK_Cancel signifies  overlay boundary */
+		//---
+        { 0, XK_Cyrillic_tse }, //New overlay
+        //---
+        { "џ", XK_Cyrillic_dzhe },
+        { 0, XK_Cancel }, /* XK_Cancel signifies  overlay boundary */
+		//---
+        { 0, XK_Cyrillic_che }, //New overlay
+        //---
+        { "ћ", XK_Serbian_tshe },
+        { "ђ", XK_Serbian_dje },
         { 0, XK_Cancel }, /* XK_Cancel signifies  overlay boundary */
 		//---
         { "🙂", 0x101f642 }, //emoji overlay
@@ -262,6 +312,7 @@ static Key overlay[OVERLAYS] = {
 
 
 static Key keys_symbols[KEYS] = {
+  { "Esc", XK_Escape, 1 },
   { "1!", XK_1, 1 },
   { "2@", XK_2, 1 },
   { "3#", XK_3, 1 },
@@ -285,31 +336,34 @@ static Key keys_symbols[KEYS] = {
   { ".>", XK_period, 1 },
   { "/?", XK_slash, 1 },
   { "\\|", XK_backslash, 1 },
+  { ";:", XK_colon, 1 },
 
   { 0 }, /* New row */
 
+  { "abc", XK_Mode_switch, 1 },
   { "☺", 0x101f642, 1 },
   { "⇤", XK_Home, 1 },
   { "←", XK_Left, 1 },
   { "→", XK_Right, 1 },
   { "⇥", XK_End, 1 },
   { "⇊", XK_Next, 1 },
-  { ";:", XK_colon, 1 },
+  { "⇈", XK_Prior, 1 },
   { "Tab", XK_Tab, 1 },
   { "⌫Bksp", XK_BackSpace, 2 },
 
   { 0 }, /* New row */
   { "↺", XK_Cancel, 1},
-  { "Shft", XK_Shift_L, 1 },
+  { "Shift", XK_Shift_L, 2 },
+  { "Ctrl", XK_Control_L, 1 },
+  { "Alt", XK_Alt_L, 1 },
+  { "", XK_space, 2 },
   { "↓", XK_Down, 1 },
   { "↑", XK_Up, 1 },
-  { "", XK_space, 2 },
-  { "Esc", XK_Escape, 1 },
-  { "Ctrl", XK_Control_L, 1 },
   { "↲ Enter", XK_Return, 2 },
 };
 
 static Key keys_functions[KEYS] = {
+  { "Esc", XK_Escape, 1 },
   { "F1", XK_F1, 1 },
   { "F2", XK_F2, 1 },
   { "F3", XK_F3, 1 },
@@ -323,6 +377,7 @@ static Key keys_functions[KEYS] = {
 
   { 0 }, /* New row */
 
+  { "≅", XK_KP_Insert, 1 },
   { "▶", XF86XK_AudioPlay, 1 },
   { "●", XF86XK_AudioRecord, 1 },
   { "■", XF86XK_AudioStop, 1 },
@@ -336,6 +391,7 @@ static Key keys_functions[KEYS] = {
 
   { 0 }, /* New row */
 
+  { "abc", XK_Mode_switch, 1 },
   { "Del", XK_Delete, 1 },
   { "⇤", XK_Home, 1 },
   { "←", XK_Left, 1 },
@@ -348,30 +404,80 @@ static Key keys_functions[KEYS] = {
 
   { 0 }, /* New row */
   { "↺", XK_Cancel, 1},
-  { "Shft", XK_Shift_L, 1 },
+  { "Shift", XK_Shift_L, 2 },
+  { "Ctrl", XK_Control_L, 1 },
+  { "Alt", XK_Alt_L, 1 },
+  { "", XK_space, 2 },
   { "↓", XK_Down, 1 },
   { "↑", XK_Up, 1 },
-  { "", XK_space, 2 },
-  { "Esc", XK_Escape, 1 },
-  { "Ctrl", XK_Control_L, 1 },
   { "↲ Enter", XK_Return, 2 },
 };
 
 
-#define LAYERS 3
+static Key keys_ru[KEYS] = {
-static Key* layers[LAYERS] = {
+        { "и", XK_Cyrillic_shorti, 1 },
+        { "ц", XK_Cyrillic_tse, 1 },
+        { "у", XK_Cyrillic_u, 1 },
+        { "к", XK_Cyrillic_ka, 1 },
+        { "е", XK_Cyrillic_ie, 1 },
+        { "н", XK_Cyrillic_en, 1 },
+        { "г", XK_Cyrillic_ghe, 1 },
+        { "ш", XK_Cyrillic_sha, 1 },
+        { "щ", XK_Cyrillic_shcha, 1 },
+        { "з", XK_Cyrillic_ze, 1 },
+        { "х", XK_Cyrillic_ha, 1 },
+
+        { 0 }, /* New row */
+
+        { "ф", XK_Cyrillic_ef, 1 },
+        { "ы", XK_Cyrillic_yeru, 1 },
+        { "в", XK_Cyrillic_ve, 1 },
+        { "а", XK_Cyrillic_a, 1 },
+        { "п", XK_Cyrillic_pe, 1 },
+        { "о", XK_Cyrillic_o, 1 },
+        { "л", XK_Cyrillic_el, 1 },
+        { "д", XK_Cyrillic_de, 1 },
+        { "ж", XK_Cyrillic_zhe, 1 },
+        { "э", XK_Cyrillic_e, 1 },
+        { "ю", XK_Cyrillic_yu, 1 },
+
+        { 0 }, /* New row */
+
+        { "123", XK_Mode_switch, 1 },
+        { "я", XK_Cyrillic_ya, 1 },
+        { "ч", XK_Cyrillic_che, 1 },
+        { "с", XK_Cyrillic_es, 1 },
+        { "м", XK_Cyrillic_em, 1 },
+        { "и", XK_Cyrillic_i, 1 },
+        { "т", XK_Cyrillic_te, 1 },
+        { "ь", XK_Cyrillic_softsign, 1 },
+        { "б", XK_Cyrillic_be, 1 },
+        { "⌫Bksp", XK_BackSpace, 2 },
+
+        { 0 }, /* New row */
+        { "↺", XK_Cancel, 1},
+        { "Shift", XK_Shift_L, 2 },
+        { "Ctrl", XK_Control_L, 1 },
+        { "Alt", XK_Alt_L, 1 },
+        { "", XK_space, 2 },
+        { "↓", XK_Down, 1 },
+        { "↑", XK_Up, 1 },
+        { "↲ Enter", XK_Return, 2 },
+};
+
+#define LAYERS 4
+static char* layer_names[LAYERS] = {
+    "en",
+    "symbols",
+    "functions",
+    "ru",
+};
+
+static Key* available_layers[LAYERS] = {
     keys_en,
     keys_symbols,
     keys_functions,
-};
+    keys_ru
-
-
-#define CYCLEMODKEY (KEYS - 3) //third last key (Escape)
-#define CYCLEMODS 3
-static Key cyclemods[CYCLEMODS] = {
-  { "Esc", XK_Escape, 1 },
-  { "Alt", XK_Alt_L, 1 },
-  { "AGr", XK_ISO_Level3_Shift, 1 },
 };
 
 

svkbd.c

@@ -67,7 +67,6 @@ static void drawkeyboard(void);
 static void drawkey(Key *k);
 static void expose(XEvent *e);
 static Key *findkey(int x, int y);
-static int iscyclemod(KeySym keysym);
 static void leavenotify(XEvent *e);
 static void press(Key *k, KeySym mod);
 static double get_press_duration();
@@ -76,9 +75,9 @@ static void setup(void);
 static void simulate_keypress(KeySym keysym);
 static void simulate_keyrelease(KeySym keysym);
 static void showoverlay(int idx);
-static void cyclemod();
 static void hideoverlay();
 static void cyclelayer();
+static void togglelayer();
 static void unpress(Key *k, KeySym mod);
 static void updatekeys();
 
@@ -101,14 +100,15 @@ static Bool running = True, isdock = False;
 static KeySym pressedmod = 0;
 static struct timeval pressbegin;
 static int currentlayer = 0;
+static int enableoverlays = 1;
 static int currentoverlay = -1; // -1 = no overlay
-static int currentcyclemod = 0;
 static KeySym overlaykeysym = 0; //keysym for which the overlay is presented
 static int releaseprotect = 0; //set to 1 after overlay is shown, protecting against immediate release
 static int tmp_keycode = 1;
 static int rows = 0, ww = 0, wh = 0, wx = 0, wy = 0;
 static char *name = "svkbd";
 static int debug = 0;
+static int numlayers = 0;
 
 static KeySym ispressingkeysym;
 
@@ -122,6 +122,8 @@ Bool sigtermd = False;
 #endif
 #include LAYOUT
 
+static Key* layers[LAYERS];
+
 void
 motionnotify(XEvent *e)
 {
@@ -210,6 +212,15 @@ cleanup(void) {
 	//      process will be dead before finger lifts - in that case we
 	//      just trigger out fake up presses for all keys
 	if (sigtermd) {
+		//handle last pending events
+		XEvent ev;
+		while (XPending(dpy)) {
+			XNextEvent(dpy, &ev);
+			if(handler[ev.type]) {
+				(handler[ev.type])(&ev); /* call handler */
+			}
+		}
+		if (debug) { printf("Cleanup: simulating key release\n"); fflush(stdout); }
 		for (i = 0; i < LENGTH(keys); i++) {
 			XTestFakeKeyEvent(dpy, XKeysymToKeycode(dpy, keys[i].keysym), False, 0);
 		}
@@ -218,6 +229,7 @@ cleanup(void) {
 	for (i = 0; i < SchemeLast; i++)
 		free(scheme[i]);
 	drw_sync(drw);
+	drw_free(drw);
 	XSync(dpy, False);
 	drw_free(drw);
 	XDestroyWindow(dpy, win);
@@ -272,7 +284,13 @@ drawkey(Key *k) {
 	drw_rect(drw, k->x, k->y, k->w, k->h, 1, 1);
 	drw_rect(drw, k->x, k->y, k->w, k->h, 0, 0);
 
-	if(k->label) {
+	if (k->keysym == XK_KP_Insert) {
+		if (enableoverlays) {
+			l = "≅";
+		} else {
+			l = "≇";
+		}
+	} else if(k->label) {
 		l = k->label;
 	} else {
 		l = XKeysymToString(k->keysym);
@@ -322,17 +340,6 @@ hasoverlay(KeySym keysym) {
 	return -1;
 }
 
-int
-iscyclemod(KeySym keysym) {
-	int i;
-	for(i = 0; i < CYCLEMODS; i++) {
-		if(cyclemods[i].keysym == keysym) {
-			return i;
-		}
-	}
-	return -1;
-}
-
 void
 leavenotify(XEvent *e) {
 	if (currentoverlay != -1) {
@@ -358,16 +365,10 @@ press(Key *k, KeySym mod) {
 	pressbegin.tv_usec = 0;
 	ispressingkeysym = 0;
 
-	int cm = iscyclemod(k->keysym);
+	if(!IsModifierKey(k->keysym)) {
-	if (cm != -1) {
+		if (enableoverlays && currentoverlay == -1)
-		if (!pressbegin.tv_sec && !pressbegin.tv_usec) {
-			//record the begin of the press, don't simulate the actual keypress yet
-			record_press_begin(k->keysym);
-		}
-	} else if(!IsModifierKey(k->keysym)) {
-		if (currentoverlay == -1)
 			overlayidx = hasoverlay(k->keysym);
-		if (overlayidx != -1) {
+		if (enableoverlays && overlayidx != -1) {
 			if (!pressbegin.tv_sec && !pressbegin.tv_usec) {
 				//record the begin of the press, don't simulate the actual keypress yet
 				record_press_begin(k->keysym);
@@ -437,6 +438,12 @@ unpress(Key *k, KeySym mod) {
 		case XK_Cancel:
 			cyclelayer();
 			break;
+		case XK_script_switch:
+			togglelayer();
+			break;
+		case XK_KP_Insert:
+			enableoverlays = !enableoverlays;
+			break;
 		case XK_Break:
 		  running = False;
 		default:
@@ -445,7 +452,7 @@ unpress(Key *k, KeySym mod) {
 	}
 
 
-	if ((pressbegin.tv_sec || pressbegin.tv_usec) && k && k->keysym == ispressingkeysym) {
+	if ((pressbegin.tv_sec || pressbegin.tv_usec) && enableoverlays && k && k->keysym == ispressingkeysym) {
 		if (currentoverlay == -1) {
 			if (get_press_duration() < overlay_delay) {
 				if (debug) { printf("Delayed simulation of press after release: %ld\n", k->keysym); fflush(stdout); }
@@ -472,7 +479,7 @@ unpress(Key *k, KeySym mod) {
 		if (k) {
 			printf("Simulation of release: %ld\n", k->keysym); fflush(stdout);
 		} else {
-			printf("Simulation of release (all keys)"); fflush(stdout);
+			printf("Simulation of release (all keys)\n"); fflush(stdout);
 		}
 	}
 
@@ -500,7 +507,7 @@ unpress(Key *k, KeySym mod) {
 		}
 	}
 
-	if (currentoverlay != -1) {
+	if (enableoverlays && currentoverlay != -1) {
 		if (releaseprotect) {
 			releaseprotect = 0;
 		} else {
@@ -516,7 +523,6 @@ run(void) {
 	fd_set fds;
 	struct timeval tv;
 	double duration = 0.0;
-	int cyclemodidx;
 
 
 	xfd = ConnectionNumber(dpy);
@@ -528,6 +534,7 @@ run(void) {
 	XFlush(dpy);
 
 	while (running) {
+		usleep(100000L);
 		FD_ZERO(&fds);
 		FD_SET(xfd, &fds);
 		if (select(xfd + 1, &fds, NULL, NULL, &tv)) {
@@ -543,19 +550,13 @@ run(void) {
 				if (debug == 2) { printf("%f\n", duration); fflush(stdout); }
 				if (get_press_duration() >= overlay_delay) {
 					if (debug) { printf("press duration %f\n", duration); fflush(stdout); }
-					cyclemodidx = iscyclemod(ispressingkeysym);
-					if (cyclemodidx != -1) {
-						cyclemod();
-					} else {
 					showoverlay(hasoverlay(ispressingkeysym));
-					}
 					pressbegin.tv_sec = 0;
 					pressbegin.tv_usec = 0;
 					ispressingkeysym = 0;
 				}
 			}
 		}
-		usleep(100000L);
 	}
 }
 
@@ -719,14 +720,20 @@ updatekeys() {
 
 void
 usage(char *argv0) {
-	fprintf(stderr, "usage: %s [-hdvD] [-g geometry] [-fn font]\n", argv0);
+	fprintf(stderr, "usage: %s [-hdvDOl] [-g geometry] [-fn font]\n", argv0);
+	fprintf(stderr, "Options:\n");
+	fprintf(stderr, "  -d         - Set Dock Window Type\n");
+	fprintf(stderr, "  -D         - Enable debug\n");
+	fprintf(stderr, "  -O         - Disable overlays\n");
+	fprintf(stderr, "  -l         - Comma separated list of layers to enable\n");
+	fprintf(stderr, "  -fn [font] - Set font (Xft, e.g: DejaVu Sans:bold:size=20)\n");
 	exit(1);
 }
 
 void
 cyclelayer() {
 	currentlayer++;
-	if (currentlayer >= LAYERS)
+	if (currentlayer >= numlayers)
 		currentlayer = 0;
 	if (debug) { printf("Cycling to layer %d\n", currentlayer); fflush(stdout); }
 	memcpy(&keys, layers[currentlayer], sizeof(keys_en));
@@ -735,28 +742,18 @@ cyclelayer() {
 }
 
 void
-cyclemod() {
+togglelayer() {
-	int i;
+	if (currentlayer > 0) {
-	//unpress all pressed keys
+		currentlayer = 0;
-	for(i = 0; i < LENGTH(keys); i++) {
+	} else if (numlayers > 1) {
-		if(keys[i].pressed) {
+		currentlayer = 1;
-			keys[i].pressed = 0;
-			drawkey(&keys[i]);
 	}
+	if (debug) { printf("Toggling layer %d\n", currentlayer); fflush(stdout); }
+	memcpy(&keys, layers[currentlayer], sizeof(keys_en));
+	updatekeys();
+	drawkeyboard();
 }
-	pressedmod = 0;
+
-	pressbegin.tv_sec = 0;
-	pressbegin.tv_usec = 0;
-	ispressingkeysym = 0;
-	currentcyclemod++;
-	if (currentcyclemod >= CYCLEMODS)
-		currentcyclemod = 0;
-	if (debug) { printf("Cycling modifier to %d\n", currentcyclemod); fflush(stdout); }
-	keys[CYCLEMODKEY].label = cyclemods[currentcyclemod].label;
-	keys[CYCLEMODKEY].keysym = cyclemods[currentcyclemod].keysym;
-	drawkey(&keys[CYCLEMODKEY]);
-	XSync(dpy, False);
-}
 
 void
 showoverlay(int idx) {
@@ -802,15 +799,58 @@ sigterm(int sig)
 {
 	running = False;
 	sigtermd = True;
+	if (debug) { printf("Sigterm received\n"); fflush(stdout); }
+}
+
+
+void
+init_layers(char * layer_names_list) {
+	if (layer_names_list == NULL) {
+		numlayers = LAYERS;
+		memcpy(&layers, &available_layers, sizeof(available_layers));
+	} else {
+		char * s;
+		int j;
+		s = strtok(layer_names_list, ",");
+		while (s != NULL) {
+			if (numlayers+1 > LAYERS) die("too many layers specified");
+			int found = 0;
+			for (j = 0; j < LAYERS; j++) {
+				if (strcmp(layer_names[j], s) == 0) {
+					layers[numlayers] = available_layers[j];
+					printf("Adding layer %s\n", s);
+					found = 1;
+					break;
+				}
+			}
+			if (!found) {
+				fprintf(stderr, "Undefined layer: %s\n", s);
+				exit(3);
+			}
+			numlayers++;
+			s = strtok(NULL,",");
+		}
+	}
 }
 
 int
 main(int argc, char *argv[]) {
 	int i, xr, yr, bitm;
 	unsigned int wr, hr;
+	char * layer_names_list = NULL;
 
 	memcpy(&keys, &keys_en, sizeof(keys_en));
 	signal(SIGTERM, sigterm);
+
+	const char* enableoverlays_env = getenv("SVKBD_ENABLEOVERLAYS");
+	if (enableoverlays_env != NULL) enableoverlays = atoi(enableoverlays_env);
+	const char* layers_env = getenv("SVKBD_LAYERS");
+	if (layers_env != NULL) {
+		layer_names_list = malloc(128);
+		strcpy(layer_names_list, layers_env);
+	}
+
+
 	for (i = 1; argv[i]; i++) {
 		if(!strcmp(argv[i], "-v")) {
 			die("svkbd-"VERSION", © 2006-2020 svkbd engineers,"
@@ -842,9 +882,18 @@ main(int argc, char *argv[]) {
 			debug = 1;
 		} else if(!strcmp(argv[i], "-h")) {
 			usage(argv[0]);
+		} else if(!strcmp(argv[i], "-O")) {
+			enableoverlays = 0;
+		} else if(!strcmp(argv[i], "-l")) {
+			if(i >= argc - 1)
+				continue;
+			if (layer_names_list == NULL) layer_names_list = malloc(128);
+			strcpy(layer_names_list, argv[i+1]);
 		}
 	}
 
+	init_layers(layer_names_list);
+
 	if(!setlocale(LC_CTYPE, "") || !XSupportsLocale())
 		fprintf(stderr, "warning: no locale support\n");
 	if(!(dpy = XOpenDisplay(0)))
@@ -853,5 +902,6 @@ main(int argc, char *argv[]) {
 	run();
 	cleanup();
 	XCloseDisplay(dpy);
+	if (layer_names_list != NULL) free(layer_names_list);
 	return 0;
 }