Update README for adding alacritty to swallow

.gitignore

@@ -0,0 +1,4 @@
+*.o
+dwm
+patches/
+*.rej

README.md

@@ -1,3 +1,12 @@
+# Changes in this build
+
+## Patches
+
+#### [Swallow](https://dwm.suckless.org/patches/swallow/) 
+1. `git apply --reject <diff file>`
+2. Manually apply any failed hunks
+3. Add your terminal of choice to your config.h (simply copy the St line from the patch)
+
 dwm - dynamic window manager
 ============================
 dwm is an extremely fast, small, and dynamic window manager for X.

config.def.h

@@ -3,6 +3,7 @@
 /* appearance */
 static const unsigned int borderpx  = 1;        /* border pixel of windows */
 static const unsigned int snap      = 32;       /* snap pixel */
+static const int swallowfloating    = 0;        /* 1 means swallow floating windows by default */
 static const int showbar            = 1;        /* 0 means no bar */
 static const int topbar             = 1;        /* 0 means bottom bar */
 static const char *fonts[]          = { "monospace:size=10" };
@@ -26,9 +27,11 @@ static const Rule rules[] = {
 	 *	WM_CLASS(STRING) = instance, class
 	 *	WM_NAME(STRING) = title
 	 */
-	/* class      instance    title       tags mask     isfloating   monitor */
+	/* class     instance  title           tags mask  isfloating  isterminal  noswallow  monitor */
-	{ "Gimp",     NULL,       NULL,       0,            1,           -1 },
+	{ "Gimp",    NULL,     NULL,           0,         1,          0,           0,        -1 },
-	{ "Firefox",  NULL,       NULL,       1 << 8,       0,           -1 },
+	{ "Firefox", NULL,     NULL,           1 << 8,    0,          0,          -1,        -1 },
+	{ "St",      NULL,     NULL,           0,         0,          1,           0,        -1 },
+	{ NULL,      NULL,     "Event Tester", 0,         0,          0,           1,        -1 }, /* xev */
 };
 
 /* layout(s) */

config.h

@@ -0,0 +1,129 @@
+#include <X11/XF86keysym.h>
+
+/* appearance */
+static const unsigned int borderpx  = 1;        /* border pixel of windows */
+static const unsigned int snap      = 32;       /* snap pixel */
+static const int swallowfloating    = 0;        /* 1 means swallow floating windows by default */
+static const int showbar            = 1;        /* 0 means no bar */
+static const int topbar             = 1;        /* 0 means bottom bar */
+static const char *fonts[]          = { "monospace:size=10" };
+static const char dmenufont[]       = "monospace:size=10";
+static const char col_gray1[]       = "#222222";
+static const char col_gray2[]       = "#444444";
+static const char col_gray3[]       = "#bbbbbb";
+static const char col_gray4[]       = "#eeeeee";
+static const char col_cyan[]        = "#005577";
+static const char *colors[][3]      = {
+	/*               fg         bg         border   */
+	[SchemeNorm] = { col_gray3, col_gray1, col_gray2 },
+	[SchemeSel]  = { col_gray4, col_cyan,  col_cyan  },
+};
+
+/* tagging */
+static const char *tags[] = { "1", "2", "3", "4", "5", "6", "7", "8", "9" };
+
+static const Rule rules[] = {
+	/* xprop(1):
+	 *	WM_CLASS(STRING) = instance, class
+	 *	WM_NAME(STRING) = title
+	 */
+	/* class     instance  title           tags mask  isfloating  isterminal  noswallow  monitor */
+	{ "Gimp",    NULL,     NULL,           0,         1,          0,           0,        -1 },
+	{ "Firefox", NULL,     NULL,           1 << 8,    0,          0,          -1,        -1 },
+	{ "St",      NULL,     NULL,           0,         0,          1,           0,        -1 },
+	{ "Alacritty",      NULL,     NULL,           0,         0,          1,           0,        -1 },
+	{ NULL,      NULL,     "Event Tester", 0,         0,          0,           1,        -1 }, /* xev */
+};
+
+/* layout(s) */
+static const float mfact     = 0.55; /* factor of master area size [0.05..0.95] */
+static const int nmaster     = 1;    /* number of clients in master area */
+static const int resizehints = 1;    /* 1 means respect size hints in tiled resizals */
+static const int lockfullscreen = 1; /* 1 will force focus on the fullscreen window */
+
+static const Layout layouts[] = {
+	/* symbol     arrange function */
+	{ "[]=",      tile },    /* first entry is default */
+	{ "><>",      NULL },    /* no layout function means floating behavior */
+	{ "[M]",      monocle },
+};
+
+/* key definitions */
+#define MODKEY Mod4Mask
+#define TAGKEYS(KEY,TAG) \
+	{ MODKEY,                       KEY,      view,           {.ui = 1 << TAG} }, \
+	{ MODKEY|ControlMask,           KEY,      toggleview,     {.ui = 1 << TAG} }, \
+	{ MODKEY|ShiftMask,             KEY,      tag,            {.ui = 1 << TAG} }, \
+	{ MODKEY|ControlMask|ShiftMask, KEY,      toggletag,      {.ui = 1 << TAG} },
+
+/* helper for spawning shell commands in the pre dwm-5.0 fashion */
+#define SHCMD(cmd) { .v = (const char*[]){ "/bin/sh", "-c", cmd, NULL } }
+
+/* commands */
+static char dmenumon[2] = "0"; /* component of dmenucmd, manipulated in spawn() */
+static const char *dmenucmd[] = { "dmenu_run", "-m", dmenumon, "-fn", dmenufont, "-nb", col_gray1, "-nf", col_gray3, "-sb", col_cyan, "-sf", col_gray4, NULL };
+static const char *termcmd[]  = { "st", NULL };
+static const char *brighter[] = { "brightnessctl", "set", "10%+", NULL };
+static const char *dimmer[]   = { "brightnessctl", "set", "10%-", NULL };
+static const char *up_vol[]   = { "pactl", "set-sink-volume", "@DEFAULT_SINK@", "+10%",   NULL };
+static const char *down_vol[] = { "pactl", "set-sink-volume", "@DEFAULT_SINK@", "-10%",   NULL };
+static const char *mute_vol[] = { "pactl", "set-sink-mute",   "@DEFAULT_SINK@", "toggle", NULL };
+
+static const Key keys[] = {
+	/* modifier                     key        function        argument */
+	{ MODKEY,                       XK_p,      spawn,          {.v = dmenucmd } },
+	{ MODKEY|ShiftMask,             XK_Return, spawn,          {.v = termcmd } },
+	{ MODKEY,                       XK_b,      togglebar,      {0} },
+	{ MODKEY,                       XK_j,      focusstack,     {.i = +1 } },
+	{ MODKEY,                       XK_k,      focusstack,     {.i = -1 } },
+	{ MODKEY,                       XK_i,      incnmaster,     {.i = +1 } },
+	{ MODKEY,                       XK_d,      incnmaster,     {.i = -1 } },
+	{ MODKEY,                       XK_h,      setmfact,       {.f = -0.05} },
+	{ MODKEY,                       XK_l,      setmfact,       {.f = +0.05} },
+	{ MODKEY,                       XK_Return, zoom,           {0} },
+	{ MODKEY,                       XK_Tab,    view,           {0} },
+	{ MODKEY|ShiftMask,             XK_c,      killclient,     {0} },
+	{ MODKEY,                       XK_t,      setlayout,      {.v = &layouts[0]} },
+	{ MODKEY,                       XK_f,      setlayout,      {.v = &layouts[1]} },
+	{ MODKEY,                       XK_m,      setlayout,      {.v = &layouts[2]} },
+	{ MODKEY,                       XK_space,  setlayout,      {0} },
+	{ MODKEY|ShiftMask,             XK_space,  togglefloating, {0} },
+	{ MODKEY,                       XK_0,      view,           {.ui = ~0 } },
+	{ MODKEY|ShiftMask,             XK_0,      tag,            {.ui = ~0 } },
+	{ MODKEY,                       XK_comma,  focusmon,       {.i = -1 } },
+	{ MODKEY,                       XK_period, focusmon,       {.i = +1 } },
+	{ MODKEY|ShiftMask,             XK_comma,  tagmon,         {.i = -1 } },
+	{ MODKEY|ShiftMask,             XK_period, tagmon,         {.i = +1 } },
+	TAGKEYS(                        XK_1,                      0)
+	TAGKEYS(                        XK_2,                      1)
+	TAGKEYS(                        XK_3,                      2)
+	TAGKEYS(                        XK_4,                      3)
+	TAGKEYS(                        XK_5,                      4)
+	TAGKEYS(                        XK_6,                      5)
+	TAGKEYS(                        XK_7,                      6)
+	TAGKEYS(                        XK_8,                      7)
+	TAGKEYS(                        XK_9,                      8)
+	{ MODKEY|ShiftMask,             XK_q,      quit,           {0} },
+	{ 0, XF86XK_MonBrightnessDown, spawn, {.v = dimmer } },
+	{ 0, XF86XK_MonBrightnessUp,   spawn, {.v = brighter } },
+	{ 0, XF86XK_AudioMute,        spawn, {.v = mute_vol } },
+	{ 0, XF86XK_AudioLowerVolume, spawn, {.v = down_vol } },
+	{ 0, XF86XK_AudioRaiseVolume, spawn, {.v = up_vol } },
+};
+
+/* button definitions */
+/* click can be ClkTagBar, ClkLtSymbol, ClkStatusText, ClkWinTitle, ClkClientWin, or ClkRootWin */
+static const Button buttons[] = {
+	/* click                event mask      button          function        argument */
+	{ ClkLtSymbol,          0,              Button1,        setlayout,      {0} },
+	{ ClkLtSymbol,          0,              Button3,        setlayout,      {.v = &layouts[2]} },
+	{ ClkWinTitle,          0,              Button2,        zoom,           {0} },
+	{ ClkStatusText,        0,              Button2,        spawn,          {.v = termcmd } },
+	{ ClkClientWin,         MODKEY,         Button1,        movemouse,      {0} },
+	{ ClkClientWin,         MODKEY,         Button2,        togglefloating, {0} },
+	{ ClkClientWin,         MODKEY,         Button3,        resizemouse,    {0} },
+	{ ClkTagBar,            0,              Button1,        view,           {0} },
+	{ ClkTagBar,            0,              Button3,        toggleview,     {0} },
+	{ ClkTagBar,            MODKEY,         Button1,        tag,            {0} },
+	{ ClkTagBar,            MODKEY,         Button3,        toggletag,      {0} },
+};

config.mk

@@ -20,10 +20,11 @@ FREETYPEINC = /usr/include/freetype2
 # OpenBSD (uncomment)
 #FREETYPEINC = ${X11INC}/freetype2
 #MANPREFIX = ${PREFIX}/man
+#KVMLIB = -lkvm
 
 # includes and libs
 INCS = -I${X11INC} -I${FREETYPEINC}
-LIBS = -L${X11LIB} -lX11 ${XINERAMALIBS} ${FREETYPELIBS}
+LIBS = -L${X11LIB} -lX11 ${XINERAMALIBS} ${FREETYPELIBS} -lX11-xcb -lxcb -lxcb-res ${KVMLIB}
 
 # flags
 CPPFLAGS = -D_DEFAULT_SOURCE -D_BSD_SOURCE -D_XOPEN_SOURCE=700L -DVERSION=\"${VERSION}\" ${XINERAMAFLAGS}

dwm.c

@@ -40,6 +40,12 @@
 #include <X11/extensions/Xinerama.h>
 #endif /* XINERAMA */
 #include <X11/Xft/Xft.h>
+#include <X11/Xlib-xcb.h>
+#include <xcb/res.h>
+#ifdef __OpenBSD__
+#include <sys/sysctl.h>
+#include <kvm.h>
+#endif /* __OpenBSD */
 
 #include "drw.h"
 #include "util.h"
@@ -91,9 +97,11 @@ struct Client {
 	int basew, baseh, incw, inch, maxw, maxh, minw, minh, hintsvalid;
 	int bw, oldbw;
 	unsigned int tags;
-	int isfixed, isfloating, isurgent, neverfocus, oldstate, isfullscreen;
+	int isfixed, isfloating, isurgent, neverfocus, oldstate, isfullscreen, isterminal, noswallow;
+	pid_t pid;
 	Client *next;
 	Client *snext;
+	Client *swallowing;
 	Monitor *mon;
 	Window win;
 };
@@ -137,6 +145,8 @@ typedef struct {
 	const char *title;
 	unsigned int tags;
 	int isfloating;
+	int isterminal;
+	int noswallow;
 	int monitor;
 } Rule;
 
@@ -233,6 +243,12 @@ static int xerrordummy(Display *dpy, XErrorEvent *ee);
 static int xerrorstart(Display *dpy, XErrorEvent *ee);
 static void zoom(const Arg *arg);
 
+static pid_t getparentprocess(pid_t p);
+static int isdescprocess(pid_t p, pid_t c);
+static Client *swallowingclient(Window w);
+static Client *termforwin(const Client *c);
+static pid_t winpid(Window w);
+
 /* variables */
 static const char broken[] = "broken";
 static char stext[256];
@@ -267,6 +283,8 @@ static Drw *drw;
 static Monitor *mons, *selmon;
 static Window root, wmcheckwin;
 
+static xcb_connection_t *xcon;
+
 /* configuration, allows nested code to access above variables */
 #include "config.h"
 
@@ -296,6 +314,8 @@ applyrules(Client *c)
 		&& (!r->class || strstr(class, r->class))
 		&& (!r->instance || strstr(instance, r->instance)))
 		{
+			c->isterminal = r->isterminal;
+			c->noswallow  = r->noswallow;
 			c->isfloating = r->isfloating;
 			c->tags |= r->tags;
 			for (m = mons; m && m->num != r->monitor; m = m->next);
@@ -414,6 +434,53 @@ attachstack(Client *c)
 	c->mon->stack = c;
 }
 
+void
+swallow(Client *p, Client *c)
+{
+
+	if (c->noswallow || c->isterminal)
+		return;
+	if (c->noswallow && !swallowfloating && c->isfloating)
+		return;
+
+	detach(c);
+	detachstack(c);
+
+	setclientstate(c, WithdrawnState);
+	XUnmapWindow(dpy, p->win);
+
+	p->swallowing = c;
+	c->mon = p->mon;
+
+	Window w = p->win;
+	p->win = c->win;
+	c->win = w;
+	updatetitle(p);
+	XMoveResizeWindow(dpy, p->win, p->x, p->y, p->w, p->h);
+	arrange(p->mon);
+	configure(p);
+	updateclientlist();
+}
+
+void
+unswallow(Client *c)
+{
+	c->win = c->swallowing->win;
+
+	free(c->swallowing);
+	c->swallowing = NULL;
+
+	/* unfullscreen the client */
+	setfullscreen(c, 0);
+	updatetitle(c);
+	arrange(c->mon);
+	XMapWindow(dpy, c->win);
+	XMoveResizeWindow(dpy, c->win, c->x, c->y, c->w, c->h);
+	setclientstate(c, NormalState);
+	focus(NULL);
+	arrange(c->mon);
+}
+
 void
 buttonpress(XEvent *e)
 {
@@ -654,6 +721,9 @@ destroynotify(XEvent *e)
 
 	if ((c = wintoclient(ev->window)))
 		unmanage(c, 1);
+
+	else if ((c = swallowingclient(ev->window)))
+		unmanage(c->swallowing, 1);
 }
 
 void
@@ -1030,12 +1100,13 @@ killclient(const Arg *arg)
 void
 manage(Window w, XWindowAttributes *wa)
 {
-	Client *c, *t = NULL;
+	Client *c, *t = NULL, *term = NULL;
 	Window trans = None;
 	XWindowChanges wc;
 
 	c = ecalloc(1, sizeof(Client));
 	c->win = w;
+	c->pid = winpid(w);
 	/* geometry */
 	c->x = c->oldx = wa->x;
 	c->y = c->oldy = wa->y;
@@ -1050,6 +1121,7 @@ manage(Window w, XWindowAttributes *wa)
 	} else {
 		c->mon = selmon;
 		applyrules(c);
+		term = termforwin(c);
 	}
 
 	if (c->x + WIDTH(c) > c->mon->wx + c->mon->ww)
@@ -1084,6 +1156,8 @@ manage(Window w, XWindowAttributes *wa)
 	c->mon->sel = c;
 	arrange(c->mon);
 	XMapWindow(dpy, c->win);
+	if (term)
+		swallow(term, c);
 	focus(NULL);
 }
 
@@ -1780,6 +1854,20 @@ unmanage(Client *c, int destroyed)
 	Monitor *m = c->mon;
 	XWindowChanges wc;
 
+	if (c->swallowing) {
+		unswallow(c);
+		return;
+	}
+
+	Client *s = swallowingclient(c->win);
+	if (s) {
+		free(s->swallowing);
+		s->swallowing = NULL;
+		arrange(m);
+		focus(NULL);
+		return;
+	}
+
 	detach(c);
 	detachstack(c);
 	if (!destroyed) {
@@ -1795,9 +1883,12 @@ unmanage(Client *c, int destroyed)
 		XUngrabServer(dpy);
 	}
 	free(c);
-	focus(NULL);
+
-	updateclientlist();
+	if (!s) {
-	arrange(m);
+		arrange(m);
+		focus(NULL);
+		updateclientlist();
+	}
 }
 
 void
@@ -2061,6 +2152,136 @@ view(const Arg *arg)
 	arrange(selmon);
 }
 
+pid_t
+winpid(Window w)
+{
+
+	pid_t result = 0;
+
+#ifdef __linux__
+	xcb_res_client_id_spec_t spec = {0};
+	spec.client = w;
+	spec.mask = XCB_RES_CLIENT_ID_MASK_LOCAL_CLIENT_PID;
+
+	xcb_generic_error_t *e = NULL;
+	xcb_res_query_client_ids_cookie_t c = xcb_res_query_client_ids(xcon, 1, &spec);
+	xcb_res_query_client_ids_reply_t *r = xcb_res_query_client_ids_reply(xcon, c, &e);
+
+	if (!r)
+		return (pid_t)0;
+
+	xcb_res_client_id_value_iterator_t i = xcb_res_query_client_ids_ids_iterator(r);
+	for (; i.rem; xcb_res_client_id_value_next(&i)) {
+		spec = i.data->spec;
+		if (spec.mask & XCB_RES_CLIENT_ID_MASK_LOCAL_CLIENT_PID) {
+			uint32_t *t = xcb_res_client_id_value_value(i.data);
+			result = *t;
+			break;
+		}
+	}
+
+	free(r);
+
+	if (result == (pid_t)-1)
+		result = 0;
+
+#endif /* __linux__ */
+
+#ifdef __OpenBSD__
+        Atom type;
+        int format;
+        unsigned long len, bytes;
+        unsigned char *prop;
+        pid_t ret;
+
+        if (XGetWindowProperty(dpy, w, XInternAtom(dpy, "_NET_WM_PID", 0), 0, 1, False, AnyPropertyType, &type, &format, &len, &bytes, &prop) != Success || !prop)
+               return 0;
+
+        ret = *(pid_t*)prop;
+        XFree(prop);
+        result = ret;
+
+#endif /* __OpenBSD__ */
+	return result;
+}
+
+pid_t
+getparentprocess(pid_t p)
+{
+	unsigned int v = 0;
+
+#ifdef __linux__
+	FILE *f;
+	char buf[256];
+	snprintf(buf, sizeof(buf) - 1, "/proc/%u/stat", (unsigned)p);
+
+	if (!(f = fopen(buf, "r")))
+		return 0;
+
+	fscanf(f, "%*u %*s %*c %u", &v);
+	fclose(f);
+#endif /* __linux__*/
+
+#ifdef __OpenBSD__
+	int n;
+	kvm_t *kd;
+	struct kinfo_proc *kp;
+
+	kd = kvm_openfiles(NULL, NULL, NULL, KVM_NO_FILES, NULL);
+	if (!kd)
+		return 0;
+
+	kp = kvm_getprocs(kd, KERN_PROC_PID, p, sizeof(*kp), &n);
+	v = kp->p_ppid;
+#endif /* __OpenBSD__ */
+
+	return (pid_t)v;
+}
+
+int
+isdescprocess(pid_t p, pid_t c)
+{
+	while (p != c && c != 0)
+		c = getparentprocess(c);
+
+	return (int)c;
+}
+
+Client *
+termforwin(const Client *w)
+{
+	Client *c;
+	Monitor *m;
+
+	if (!w->pid || w->isterminal)
+		return NULL;
+
+	for (m = mons; m; m = m->next) {
+		for (c = m->clients; c; c = c->next) {
+			if (c->isterminal && !c->swallowing && c->pid && isdescprocess(c->pid, w->pid))
+				return c;
+		}
+	}
+
+	return NULL;
+}
+
+Client *
+swallowingclient(Window w)
+{
+	Client *c;
+	Monitor *m;
+
+	for (m = mons; m; m = m->next) {
+		for (c = m->clients; c; c = c->next) {
+			if (c->swallowing && c->swallowing->win == w)
+				return c;
+		}
+	}
+
+	return NULL;
+}
+
 Client *
 wintoclient(Window w)
 {
@@ -2150,10 +2371,12 @@ main(int argc, char *argv[])
 		fputs("warning: no locale support\n", stderr);
 	if (!(dpy = XOpenDisplay(NULL)))
 		die("dwm: cannot open display");
+	if (!(xcon = XGetXCBConnection(dpy)))
+		die("dwm: cannot get xcb connection\n");
 	checkotherwm();
 	setup();
 #ifdef __OpenBSD__
-	if (pledge("stdio rpath proc exec", NULL) == -1)
+	if (pledge("stdio rpath proc exec ps", NULL) == -1)
 		die("pledge");
 #endif /* __OpenBSD__ */
 	scan();