Add layout "horizontile"

config.def.h

@@ -41,6 +41,7 @@ static const Layout layouts[] = {
 	{ layouts_symbol_monocle,        monocle }, /* first entry is default */
 	{ layouts_symbol_floating,       NULL },    /* no layout function means floating behavior */
 	{ layouts_symbol_tile,           tile },
+	{ layouts_symbol_horizontile,    horizontile },
 	{ layouts_symbol_centeredmaster, centeredmaster },
 };
 
@@ -74,10 +75,11 @@ static Key keys[] = {
 	{ MODKEY,                       XK_Return, zoom,           {0} },
 	{ MODKEY,                       XK_Tab,    view,           {0} },
 	{ MODKEY|ShiftMask,             XK_x,      killclient,     {0} },
-	{ MODKEY,                       XK_m,      setlayout,      {.v = &layouts[0]} },
-	{ MODKEY,                       XK_f,      setlayout,      {.v = &layouts[1]} },
-	{ MODKEY,                       XK_t,      setlayout,      {.v = &layouts[2]} },
-	{ MODKEY,                       XK_u,      setlayout,      {.v = &layouts[3]} },
+	{ MODKEY,                       XK_m,      setlayout,      {.v = &layouts[0]} }, // Monocle
+	{ MODKEY,                       XK_f,      setlayout,      {.v = &layouts[1]} }, // Floating
+	{ MODKEY,                       XK_t,      setlayout,      {.v = &layouts[2]} }, // Tile
+	{ MODKEY|ShiftMask,             XK_t,      setlayout,      {.v = &layouts[3]} }, // Horizontile
+	{ MODKEY,                       XK_u,      setlayout,      {.v = &layouts[4]} }, // Centeredmaster
 	{ MODKEY,                       XK_space,  setlayout,      {0} },
 	{ MODKEY|ShiftMask,             XK_space,  togglefloating, {0} },
 	{ MODKEY,                       XK_0,      view,           {.ui = ~0 } },

dwm.c

@@ -212,6 +212,7 @@ static unsigned int getsystraywidth();
 static int gettextprop(Window w, Atom atom, char *text, unsigned int size);
 static void grabbuttons(Client *c, int focused);
 static void grabkeys(void);
+static void horizontile(Monitor *);
 static void incnmaster(const Arg *arg);
 static void keypress(XEvent *e);
 static void killclient(const Arg *arg);

dwm/layouts.c

@@ -98,6 +98,74 @@ centeredmaster(Monitor *m)
 	}
 }
 
+void
+horizontile(Monitor *m)
+{
+	unsigned int n = 0;
+	for (Client *c = nexttiled(m->clients); c; c = nexttiled(c->next), ++n);
+	if (n == 0) return;
+
+	const bool is_fullscreen = m->sel == NULL ? false : m->sel->isfullscreen;
+
+	const int gap_size = helpers_gap_size(n, is_fullscreen, is_fullscreen);
+	const int border_width = helpers_border_width(n, is_fullscreen, is_fullscreen);
+
+	const int top_left_half_gap = gap_size / 2;
+	const int bottom_right_half_gap = gap_size - top_left_half_gap;
+
+	const unsigned int mh = n > m->nmaster ? (m->nmaster ? m->wh * m->mfact : 0) : m->wh;
+
+	Client *c = nexttiled(m->clients);
+
+	for (unsigned int i = 0, mx = 0, tx = 0; c; c = nexttiled(c->next), ++i) {
+		if (i < m->nmaster) {
+			const unsigned int w = (m->ww - mx) / (MIN(n, m->nmaster) - i);
+
+			const unsigned int left_gap   = i == 0 ? gap_size : top_left_half_gap;
+			const unsigned int top_gap    = gap_size;
+			const unsigned int right_gap  = (i == m->nmaster - 1 || i == n - 1) ? gap_size : bottom_right_half_gap;
+			const unsigned int bottom_gap = n <= m->nmaster ? gap_size : bottom_right_half_gap;
+
+			resize(
+				c,
+				m->wx + mx + left_gap,
+				m->wy + top_gap,
+				w - 2 * border_width - left_gap - right_gap,
+				mh - 2 * border_width - top_gap - bottom_gap,
+				border_width,
+				0
+			);
+
+			// FIXME: maybe need + left_gap + right_gap
+			if (mx + WIDTH(c) < m->ww) {
+				mx += WIDTH(c) + left_gap + right_gap;
+			}
+		} else {
+			const unsigned int w = (m->ww - tx) / (n - i);
+
+			const unsigned int left_gap   = i == m->nmaster ? gap_size : top_left_half_gap;
+			const unsigned int top_gap    = m->nmaster == 0 ? gap_size : top_left_half_gap;
+			const unsigned int right_gap  = (i == n - 1) ? gap_size : bottom_right_half_gap;
+			const unsigned int bottom_gap = gap_size;
+
+			resize(
+				c,
+				m->wx + tx + left_gap,
+				m->wy + mh + top_gap,
+				w - 2 * border_width - left_gap - right_gap,
+				m->wh - mh - 2 * border_width - top_gap - bottom_gap,
+				border_width,
+				0
+			);
+
+			// FIXME: maybe need + left_gap + right_gap
+			if (tx + WIDTH(c) < m->ww) {
+				tx += WIDTH(c) + left_gap + right_gap;
+			}
+		}
+	}
+}
+
 void
 monocle(Monitor *m)
 {
@@ -162,6 +230,7 @@ tile(Monitor *m)
 				0
 			);
 
+			// FIXME: maybe need + top_gap + bottom_gap
 			if (my + HEIGHT(c) < m->wh) {
 				my += HEIGHT(c) + top_gap + bottom_gap;
 			}
@@ -183,6 +252,7 @@ tile(Monitor *m)
 				0
 			);
 
+			// FIXME: maybe need + top_gap + bottom_gap
 			if (ty + HEIGHT(c) < m->wh) {
 				ty += HEIGHT(c) + top_gap + bottom_gap;
 			}

layouts.c

@@ -84,6 +84,21 @@ void layouts_symbol_tile(
 	strncpy(buffer, tmp, buffer_size);
 }
 
+void layouts_symbol_horizontile(
+	char *const buffer,
+	const size_t buffer_size,
+	const unsigned int clients_in_master,
+	const unsigned int visible_clients
+) {
+	// TODO: maybe we should assert
+	if (buffer == NULL) return;
+
+	char tmp[TMP_BUFFER_SIZE];
+	sprintf(tmp, "v{%u/%u}v", clients_in_master, visible_clients);
+	tmp[(buffer_size > TMP_BUFFER_SIZE ? TMP_BUFFER_SIZE : buffer_size) - 1] = '\0';
+	strncpy(buffer, tmp, buffer_size);
+}
+
 void layouts_symbol_centeredmaster(
 	char *const buffer,
 	const size_t buffer_size,

layouts.h

@@ -46,6 +46,13 @@ void layouts_symbol_tile(
 	unsigned int visible_clients
 );
 
+void layouts_symbol_horizontile(
+	char *buffer,
+	size_t buffer_size,
+	unsigned int clients_in_master,
+	unsigned int visible_clients
+);
+
 void layouts_symbol_centeredmaster(
 	char *buffer,
 	size_t buffer_size,