downdated swallow patch

config.def.h

@@ -66,14 +66,14 @@ static Sp scratchpads[] = {
 /* tagging */
 static const char *tags[] = { "1", "2", "3", "4", "5", "6", "7", "8", "9" };
 static const Rule rules[] = {
-	/* class     instance  title           tags mask  isfloating  monitor */
+	/* class     instance  title           tags mask  isfloating isterminal noswallow   monitor */
-  { NULL,      "spterm0",  NULL,           SPTAG(0),  1,          -1 },
+  { NULL,      "spterm0",  NULL,           SPTAG(0),  1,       1,         0,          -1 },
-  { NULL,      "spterm1",  NULL,           SPTAG(1),  1,          -1 },
+  { NULL,      "spterm1",  NULL,           SPTAG(1),  1,       1,         0,          -1 },
-  { NULL,      "spterm2",  NULL,           SPTAG(2),  1,          -1 },
+  { NULL,      "spterm2",  NULL,           SPTAG(2),  1,       1,         0,          -1 },
-  { NULL,      "spterm3",  NULL,           SPTAG(3),  1,          -1 },
+  { NULL,      "spterm3",  NULL,           SPTAG(3),  1,       1,         0,          -1 },
-  { NULL,      "spterm4",  NULL,           SPTAG(4),  1,          -1 },
+  { NULL,      "spterm4",  NULL,           SPTAG(4),  1,       1,         0,          -1 },
-  { NULL,      "spterm5",  NULL,           SPTAG(5),  1,          -1 },
+  { NULL,      "spterm5",  NULL,           SPTAG(5),  1,       1,         0,          -1 },
-  { NULL,      "spterm6",  NULL,           SPTAG(6),  1,          -1 },
+  { NULL,      "spterm6",  NULL,           SPTAG(6),  1,       1,         0,          -1 },
 };
 
 

config.mk

@@ -23,7 +23,7 @@ FREETYPEINC = /usr/include/freetype2
 
 # 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
 
 # flags
 CPPFLAGS = -D_DEFAULT_SOURCE -D_BSD_SOURCE -D_XOPEN_SOURCE=700L -DVERSION=\"${VERSION}\" ${XINERAMAFLAGS}

dwm.c

@@ -40,6 +40,8 @@
 #include <X11/extensions/Xinerama.h>
 #endif /* XINERAMA */
 #include <X11/Xft/Xft.h>
+#include <X11/Xlib-xcb.h>
+#include <xcb/res.h>
 
 #include "drw.h"
 #include "util.h"
@@ -95,9 +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;
 };
@@ -142,6 +146,8 @@ typedef struct {
 	const char *title;
 	unsigned int tags;
 	int isfloating;
+	int isterminal;
+	int noswallow;
 	int monitor;
 } Rule;
 
@@ -173,6 +179,7 @@ static void focus(Client *c);
 static void focusin(XEvent *e);
 static void focusmon(const Arg *arg);
 static void focusstack(const Arg *arg);
+static pid_t getparentprocess(pid_t p);
 static Atom getatomprop(Client *c, Atom prop);
 static int getrootptr(int *x, int *y);
 static long getstate(Window w);
@@ -180,6 +187,7 @@ 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 incnmaster(const Arg *arg);
+static int isdescprocess(pid_t p, pid_t c);
 static void keypress(XEvent *e);
 static void killclient(const Arg *arg);
 static void manage(Window w, XWindowAttributes *wa);
@@ -213,8 +221,10 @@ static void showhide(Client *c);
 static void sighup(int unused);
 static void sigterm(int unused);
 static void spawn(const Arg *arg);
+static Client *swallowingclient(Window w);
 static void tag(const Arg *arg);
 static void tagmon(const Arg *arg);
+static Client *termforwin(const Client *c);
 static void tile(Monitor *m);
 static void togglebar(const Arg *arg);
 static void togglefloating(const Arg *arg);
@@ -235,6 +245,7 @@ static void updatetitle(Client *c);
 static void updatewindowtype(Client *c);
 static void updatewmhints(Client *c);
 static void view(const Arg *arg);
+static pid_t winpid(Window w);
 static Client *wintoclient(Window w);
 static Monitor *wintomon(Window w);
 static int xerror(Display *dpy, XErrorEvent *ee);
@@ -277,6 +288,8 @@ 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"
 
@@ -306,6 +319,7 @@ applyrules(Client *c)
 		&& (!r->class || strstr(class, r->class))
 		&& (!r->instance || strstr(instance, r->instance)))
 		{
+			c->isterminal = r->isterminal;
 			c->isfloating = r->isfloating;
 			c->tags |= r->tags;
 			if ((r->tags & SPTAGMASK) && r->isfloating) {
@@ -429,6 +443,47 @@ attachstack(Client *c)
 	c->mon->stack = c;
 }
 
+void
+swallow(Client *p, Client *c)
+{
+	if (c->noswallow || c->isterminal)
+		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);
+	arrange(p->mon);
+	XMoveResizeWindow(dpy, p->win, p->x, p->y, p->w, p->h);
+	configure(p);
+	updateclientlist();
+}
+
+void
+unswallow(Client *c)
+{
+	c->win = c->swallowing->win;
+
+	free(c->swallowing);
+	c->swallowing = NULL;
+
+	updatetitle(c);
+	arrange(c->mon);
+	XMapWindow(dpy, c->win);
+	XMoveResizeWindow(dpy, c->win, c->x, c->y, c->w, c->h);
+	configure(c);
+	setclientstate(c, NormalState);
+}
+
 void
 buttonpress(XEvent *e)
 {
@@ -494,7 +549,7 @@ cleanup(void)
 	selmon->lt[selmon->sellt] = &foo;
 	for (m = mons; m; m = m->next)
 		while (m->stack)
-			unmanage(m->stack, 0);
+			unmanage(m->stack, 0); // XXX - unmanage swallowing windows too
 	XUngrabKey(dpy, AnyKey, AnyModifier, root);
 	while (mons)
 		cleanupmon(mons);
@@ -670,6 +725,9 @@ destroynotify(XEvent *e)
 
 	if ((c = wintoclient(ev->window)))
 		unmanage(c, 1);
+
+	else if ((c = swallowingclient(ev->window)))
+		unmanage(c->swallowing, 1);
 }
 
 void
@@ -1046,12 +1104,13 @@ 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;
@@ -1066,6 +1125,7 @@ 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)
@@ -1100,6 +1160,8 @@ manage(Window w, XWindowAttributes *wa)
 	c->mon->sel = c;
 	arrange(c->mon);
 	XMapWindow(dpy, c->win);
+	if (term)
+		swallow(term, c);
 	focus(NULL);
 }
 
@@ -1921,6 +1983,20 @@ 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) {
@@ -1936,9 +2012,12 @@ unmanage(Client *c, int destroyed)
 		XUngrabServer(dpy);
 	}
 	free(c);
+
+	if (!s) {
+		arrange(m);
 		focus(NULL);
 		updateclientlist();
-	arrange(m);
+	}
 }
 
 void
@@ -2202,16 +2281,116 @@ view(const Arg *arg)
 	arrange(selmon);
 }
 
+pid_t
+winpid(Window w)
+{
+	pid_t result = 0;
+
+	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;
+	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__ */
+
+	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)
 {
 	Client *c;
 	Monitor *m;
 
-	for (m = mons; m; m = m->next)
+	for (m = mons; m; m = m->next) {
-		for (c = m->clients; c; c = c->next)
+		for (c = m->clients; c; c = c->next) {
 			if (c->win == w)
 				return c;
+		}
+	}
+
 	return NULL;
 }
 
@@ -2291,6 +2470,8 @@ 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__

patches/dwm-swallow-20160717-56a31dc.diff

@@ -0,0 +1,381 @@
+diff --git a/config.def.h b/config.def.h
+index fd77a07..69976b3 100644
+--- a/config.def.h
++++ b/config.def.h
+@@ -26,9 +26,10 @@ static const Rule rules[] = {
+ 	 *	WM_CLASS(STRING) = instance, class
+ 	 *	WM_NAME(STRING) = title
+ 	 */
+-	/* class      instance    title       tags mask     isfloating   monitor */
+-	{ "Gimp",     NULL,       NULL,       0,            1,           -1 },
+-	{ "Firefox",  NULL,       NULL,       1 << 8,       0,           -1 },
++	/* class      instance    title       tags mask     isfloating   isterminal noswallow monitor */
++	{ "Gimp",     NULL,       NULL,       0,            1,           0,         0,        -1 },
++	{ "Firefox",  NULL,       NULL,       1 << 8,       0,           0,         0,        -1 },
++	{ "st",       NULL,       NULL,       0,            0,           1,         1,        -1 },
+ };
+ 
+ /* layout(s) */
+diff --git a/config.mk b/config.mk
+index 80dc936..5ed14e3 100644
+--- a/config.mk
++++ b/config.mk
+@@ -22,7 +22,7 @@ FREETYPEINC = /usr/include/freetype2
+ 
+ # includes and libs
+ INCS = -I${X11INC} -I${FREETYPEINC}
+-LIBS = -L${X11LIB} -lX11 ${XINERAMALIBS} ${FREETYPELIBS}
++LIBS = -L${X11LIB} -lX11 ${XINERAMALIBS} ${FREETYPELIBS} -lX11-xcb -lxcb -lxcb-res
+ 
+ # flags
+ CPPFLAGS = -D_DEFAULT_SOURCE -D_BSD_SOURCE -D_POSIX_C_SOURCE=2 -DVERSION=\"${VERSION}\" ${XINERAMAFLAGS}
+diff --git a/dwm.c b/dwm.c
+index b2bc9bd..528df2f 100644
+--- a/dwm.c
++++ b/dwm.c
+@@ -40,6 +40,8 @@
+ #include <X11/extensions/Xinerama.h>
+ #endif /* XINERAMA */
+ #include <X11/Xft/Xft.h>
++#include <X11/Xlib-xcb.h>
++#include <xcb/res.h>
+ 
+ #include "drw.h"
+ #include "util.h"
+@@ -93,9 +95,11 @@ struct Client {
+ 	int basew, baseh, incw, inch, maxw, maxh, minw, minh;
+ 	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;
+ };
+@@ -139,6 +143,8 @@ typedef struct {
+ 	const char *title;
+ 	unsigned int tags;
+ 	int isfloating;
++	int isterminal;
++	int noswallow;
+ 	int monitor;
+ } Rule;
+ 
+@@ -171,12 +177,14 @@ static void focus(Client *c);
+ static void focusin(XEvent *e);
+ static void focusmon(const Arg *arg);
+ static void focusstack(const Arg *arg);
++static pid_t getparentprocess(pid_t p);
+ static int getrootptr(int *x, int *y);
+ static long getstate(Window w);
+ 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 incnmaster(const Arg *arg);
++static int isdescprocess(pid_t p, pid_t c);
+ static void keypress(XEvent *e);
+ static void killclient(const Arg *arg);
+ static void manage(Window w, XWindowAttributes *wa);
+@@ -207,8 +215,10 @@ static void setup(void);
+ static void showhide(Client *c);
+ static void sigchld(int unused);
+ static void spawn(const Arg *arg);
++static Client *swallowingclient(Window w);
+ static void tag(const Arg *arg);
+ static void tagmon(const Arg *arg);
++static Client *termforwin(const Client *c);
+ static void tile(Monitor *);
+ static void togglebar(const Arg *arg);
+ static void togglefloating(const Arg *arg);
+@@ -228,6 +238,7 @@ static void updatewindowtype(Client *c);
+ static void updatetitle(Client *c);
+ static void updatewmhints(Client *c);
+ static void view(const Arg *arg);
++static pid_t winpid(Window w);
+ static Client *wintoclient(Window w);
+ static Monitor *wintomon(Window w);
+ static int xerror(Display *dpy, XErrorEvent *ee);
+@@ -269,6 +280,8 @@ static Drw *drw;
+ static Monitor *mons, *selmon;
+ static Window root;
+ 
++static xcb_connection_t *xcon;
++
+ /* configuration, allows nested code to access above variables */
+ #include "config.h"
+ 
+@@ -298,6 +311,7 @@ applyrules(Client *c)
+ 		&& (!r->class || strstr(class, r->class))
+ 		&& (!r->instance || strstr(instance, r->instance)))
+ 		{
++			c->isterminal = r->isterminal;
+ 			c->isfloating = r->isfloating;
+ 			c->tags |= r->tags;
+ 			for (m = mons; m && m->num != r->monitor; m = m->next);
+@@ -415,6 +429,47 @@ attachstack(Client *c)
+ }
+ 
+ void
++swallow(Client *p, Client *c)
++{
++	if (c->noswallow || c->isterminal)
++		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);
++	arrange(p->mon);
++	XMoveResizeWindow(dpy, p->win, p->x, p->y, p->w, p->h);
++	configure(p);
++	updateclientlist();
++}
++
++void
++unswallow(Client *c)
++{
++	c->win = c->swallowing->win;
++
++	free(c->swallowing);
++	c->swallowing = NULL;
++
++	updatetitle(c);
++	arrange(c->mon);
++	XMapWindow(dpy, c->win);
++	XMoveResizeWindow(dpy, c->win, c->x, c->y, c->w, c->h);
++	configure(c);
++	setclientstate(c, NormalState);
++}
++
++void
+ buttonpress(XEvent *e)
+ {
+ 	unsigned int i, x, click;
+@@ -477,7 +531,7 @@ cleanup(void)
+ 	selmon->lt[selmon->sellt] = &foo;
+ 	for (m = mons; m; m = m->next)
+ 		while (m->stack)
+-			unmanage(m->stack, 0);
++			unmanage(m->stack, 0); // XXX - unmanage swallowing windows too
+ 	XUngrabKey(dpy, AnyKey, AnyModifier, root);
+ 	while (mons)
+ 		cleanupmon(mons);
+@@ -665,6 +719,9 @@ destroynotify(XEvent *e)
+ 
+ 	if ((c = wintoclient(ev->window)))
+ 		unmanage(c, 1);
++
++	else if ((c = swallowingclient(ev->window)))
++		unmanage(c->swallowing, 1);
+ }
+ 
+ void
+@@ -1034,12 +1091,13 @@ 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;
+@@ -1054,6 +1112,7 @@ manage(Window w, XWindowAttributes *wa)
+ 	} else {
+ 		c->mon = selmon;
+ 		applyrules(c);
++		term = termforwin(c);
+ 	}
+ 
+ 	if (c->x + WIDTH(c) > c->mon->mx + c->mon->mw)
+@@ -1090,6 +1149,8 @@ manage(Window w, XWindowAttributes *wa)
+ 	c->mon->sel = c;
+ 	arrange(c->mon);
+ 	XMapWindow(dpy, c->win);
++	if (term)
++		swallow(term, c);
+ 	focus(NULL);
+ }
+ 
+@@ -1757,6 +1818,20 @@ 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;
++	}
++
+ 	/* The server grab construct avoids race conditions. */
+ 	detach(c);
+ 	detachstack(c);
+@@ -1772,9 +1847,12 @@ unmanage(Client *c, int destroyed)
+ 		XUngrabServer(dpy);
+ 	}
+ 	free(c);
+-	focus(NULL);
+-	updateclientlist();
+-	arrange(m);
++
++	if (!s) {
++		arrange(m);
++		focus(NULL);
++		updateclientlist();
++	}
+ }
+ 
+ void
+@@ -2039,16 +2117,116 @@ view(const Arg *arg)
+ 	arrange(selmon);
+ }
+ 
++pid_t
++winpid(Window w)
++{
++	pid_t result = 0;
++
++	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;
++	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__ */
++
++	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)
+ {
+ 	Client *c;
+ 	Monitor *m;
+ 
+-	for (m = mons; m; m = m->next)
+-		for (c = m->clients; c; c = c->next)
++	for (m = mons; m; m = m->next) {
++		for (c = m->clients; c; c = c->next) {
+ 			if (c->win == w)
+ 				return c;
++		}
++	}
++
+ 	return NULL;
+ }
+ 
+@@ -2130,6 +2308,8 @@ main(int argc, char *argv[])
+ 		fputs("warning: no locale support\n", stderr);
+ 	if (!(dpy = XOpenDisplay(NULL)))
+ 		die("dwm: cannot open display\n");
++	if (!(xcon = XGetXCBConnection(dpy)))
++		die("dwm: cannot get xcb connection\n");
+ 	checkotherwm();
+ 	setup();
+ 	scan();