support fullscreen toggle

README.md

@@ -1,7 +1,7 @@
 cerberus
 ========
 
-* Designed for wide screens.
+* Designed for wide screens, including multi-head support.
 * Static tiling; you get just three fixed asymmetric tiles and windows never move automatically.
 * Bare minimum EWMH to support panels and [simpleswitcher](https://github.com/seanpringle/simpleswitcher)
 * A few keyboard controls for moving, focusing, cycling, closing, and finding windows.

cerberus.c

@@ -182,6 +182,8 @@ client* window_client(Window win)
 			? (c->attr.y > m->y + m->h/2 ? SPOT3: SPOT2)
 				: SPOT1;
 
+		window_get_atom_prop(c->window, atoms[_NET_WM_STATE], c->states, MAX_NET_WM_STATES);
+
 		if (c->visible)
 		{
 			XWMHints *hints = XGetWMHints(display, c->window);
@@ -202,6 +204,55 @@ client* window_client(Window win)
 	return NULL;
 }
 
+// check _NET_WM_STATE
+int client_state(client *c, Atom state)
+{
+	int i;
+	for (i = 0; i < MAX_NET_WM_STATES && c->states[i]; i++)
+		if (c->states[i] == state)
+			return 1;
+	return 0;
+}
+
+int client_add_state(client *c, Atom state)
+{
+	int i;
+	for (i = 0; i < MAX_NET_WM_STATES; i++)
+	{
+		if (c->states[i]) continue;
+
+		c->states[i] = state;
+		window_set_atom_prop(c->window, atoms[_NET_WM_STATE], c->states, i+1);
+		return 1;
+	}
+	return 0;
+}
+
+int client_drop_state(client *c, Atom state)
+{
+	int i, j;
+	for (i = 0, j = 0; i < MAX_NET_WM_STATES && c->states[i]; i++)
+	{
+		if (c->states[i] == state) continue;
+		c->states[i] = c->states[j++];
+	}
+	window_set_atom_prop(c->window, atoms[_NET_WM_STATE], c->states, j);
+	int rc = i != j ? 1:0;
+
+	for (; j < MAX_NET_WM_STATES; j++)
+		c->states[j] = None;
+
+	return rc;
+}
+
+void client_toggle_state(client *c, Atom state)
+{
+	if (client_state(c, state))
+		client_drop_state(c, state);
+	else
+		client_add_state(c, state);
+}
+
 // build a list of visible windows
 void windows_visible(stack *s)
 {
@@ -278,6 +329,13 @@ void client_close(client *c)
 void client_position(client *c, int x, int y, int w, int h)
 {
 	if (!c) return;
+	monitor *m = &monitors[c->monitor];
+
+	if (client_state(c, atoms[_NET_WM_STATE_FULLSCREEN]))
+	{
+		XMoveResizeWindow(display, c->window, m->x, m->y, m->w, m->h);
+		return;
+	}
 
 	w -= BORDER*2; h -= BORDER*2;
 
@@ -319,8 +377,6 @@ void client_position(client *c, int x, int y, int w, int h)
 	if (w < sw) x += (sw-w)/2;
 	if (h < sh) y += (sh-h)/2;
 
-	monitor *m = &monitors[c->monitor];
-
 	// bump onto screen
 	x = MAX(0, MIN(x, m->x + m->w - w - BORDER*2));
 	y = MAX(0, MIN(y, m->y + m->h - h - BORDER*2));
@@ -556,7 +612,7 @@ void window_listen(Window win)
 void client_review(client *c)
 {
 	XSetWindowBorder(display, c->window, color_get(c->window == current ? BORDER_FOCUS: BORDER_BLUR));
-	XSetWindowBorderWidth(display, c->window, BORDER);
+	XSetWindowBorderWidth(display, c->window, client_state(c, atoms[_NET_WM_STATE_FULLSCREEN]) ? 0: BORDER);
 }
 
 // ------- event handlers --------
@@ -734,6 +790,11 @@ void key_press(XKeyEvent *e)
 					client_spot(c, c->spot, 1);
 				}
 				break;
+			case ACTION_FULLSCREEN_TOGGLE:
+				client_toggle_state(c, atoms[_NET_WM_STATE_FULLSCREEN]);
+				client_review(c);
+				client_spot(c, c->spot, 1);
+				break;
 		}
 	}
 	switch (act)

cerberus.h

@@ -63,13 +63,15 @@ typedef struct {
 monitor monitors[MAX_MONITORS];
 int nmonitors;
 
+#define MAX_NET_WM_STATES 5
+
 typedef struct {
 	Window window;
 	XWindowAttributes attr;
 	XWMHints hints;
 	XSizeHints size;
 	Window transient_for;
-	Atom type;
+	Atom type, states[MAX_NET_WM_STATES];
 	short monitor, spot, visible, trans, manage, input, urgent;
 } client;
 
@@ -109,6 +111,8 @@ int struts[4] = { 0, 0, 0, 0 };
 	X(_NET_WM_WINDOW_TYPE_DIALOG),\
 	X(_NET_CLIENT_LIST_STACKING),\
 	X(_NET_WM_STATE),\
+	X(_NET_WM_STATE_FULLSCREEN),\
+	X(_NET_WM_STATE_DEMANDS_ATTENTION),\
 	X(WM_PROTOCOLS)
 
 enum { GENERAL_ATOMS(ATOM_ENUM), ATOMS };
@@ -134,6 +138,7 @@ enum {
 	ACTION_MOVE_MONITOR_DEC,
 	ACTION_FOCUS_MONITOR_INC,
 	ACTION_FOCUS_MONITOR_DEC,
+	ACTION_FULLSCREEN_TOGGLE,
 	ACTIONS
 };
 

config.h

@@ -63,6 +63,9 @@ binding keys[] = {
 	// Gracefully close the current window.
 	{ .mod = Mod4Mask, .key = XK_Escape, .act = ACTION_CLOSE },
 
+	// Toggle current window full screen.
+	{ .mod = Mod4Mask, .key = XK_f, .act = ACTION_FULLSCREEN_TOGGLE },
+
 	// Switch focus between monitors.
 	{ .mod = Mod4Mask, .key = XK_Right, .act = ACTION_FOCUS_MONITOR_INC },
 	{ .mod = Mod4Mask, .key = XK_Left,  .act = ACTION_FOCUS_MONITOR_DEC },

proto.h

@@ -10,6 +10,10 @@ void window_set_cardinal_prop(Window w, Atom prop, unsigned long *values, int co
 void ewmh_client_list();
 void ewmh_active_window(Window w);
 client* window_client(Window win);
+int client_state(client *c, Atom state);
+int client_add_state(client *c, Atom state);
+int client_drop_state(client *c, Atom state);
+void client_toggle_state(client *c, Atom state);
 void windows_visible(stack *s);
 int window_message(Window target, Window subject, Atom atom, unsigned long protocol, unsigned long mask);
 void client_free(client *c);