1/* See LICENSE file for copyright and license details.
   2 *
   3 * dynamic window manager is designed like any other X client as well. It is
   4 * driven through handling X events. In contrast to other X clients, a window
   5 * manager selects for SubstructureRedirectMask on the root window, to receive
   6 * events about window (dis-)appearance.  Only one X connection at a time is
   7 * allowed to select for this event mask.
   8 *
   9 * The event handlers of dwm are organized in an array which is accessed
  10 * whenever a new event has been fetched. This allows event dispatching
  11 * in O(1) time.
  12 *
  13 * Each child of the root window is called a client, except windows which have
  14 * set the override_redirect flag.  Clients are organized in a linked client
  15 * list on each monitor, the focus history is remembered through a stack list
  16 * on each monitor. Each client contains a bit array to indicate the tags of a
  17 * client.
  18 *
  19 * Keys and tagging rules are organized as arrays and defined in config.h.
  20 *
  21 * To understand everything else, start reading main().
  22 */
  23#include <errno.h>
  24#include <locale.h>
  25#include <stdarg.h>
  26#include <signal.h>
  27#include <stdio.h>
  28#include <stdlib.h>
  29#include <string.h>
  30#include <unistd.h>
  31#include <sys/types.h>
  32#include <sys/wait.h>
  33#include <X11/cursorfont.h>
  34#include <X11/keysym.h>
  35#include <X11/Xatom.h>
  36#include <X11/Xlib.h>
  37#include <X11/Xproto.h>
  38#include <X11/Xutil.h>
  39#ifdef XINERAMA
  40#include <X11/extensions/Xinerama.h>
  41#endif /* XINERAMA */
  42
  43#include "drw.h"
  44#include "util.h"
  45
  46/* macros */
  47#define BUTTONMASK              (ButtonPressMask|ButtonReleaseMask)
  48#define CLEANMASK(mask)         (mask & ~(numlockmask|LockMask) & (ShiftMask|ControlMask|Mod1Mask|Mod2Mask|Mod3Mask|Mod4Mask|Mod5Mask))
  49#define INTERSECT(x,y,w,h,m)    (MAX(0, MIN((x)+(w),(m)->wx+(m)->ww) - MAX((x),(m)->wx)) \
  50                               * MAX(0, MIN((y)+(h),(m)->wy+(m)->wh) - MAX((y),(m)->wy)))
  51#define ISVISIBLE(C)            ((C->tags & C->mon->tagset[C->mon->seltags]))
  52#define LENGTH(X)               (sizeof X / sizeof X[0])
  53#define MOUSEMASK               (BUTTONMASK|PointerMotionMask)
  54#define WIDTH(X)                ((X)->w + 2 * (X)->bw)
  55#define HEIGHT(X)               ((X)->h + 2 * (X)->bw)
  56#define TAGMASK                 ((1 << LENGTH(tags)) - 1)
  57#define TEXTW(X)                (drw_font_getexts_width(drw->font, X, strlen(X)) + drw->font->h)
  58
  59/* enums */
  60enum { CurNormal, CurResize, CurMove, CurLast };        /* cursor */
  61enum { ColBorder, ColFG, ColBG, ColLast };              /* color */
  62enum { NetSupported, NetWMName, NetWMState,
  63       NetWMFullscreen, NetActiveWindow, NetWMWindowType,
  64       NetWMWindowTypeDialog, NetClientList, NetLast };     /* EWMH atoms */
  65enum { WMProtocols, WMDelete, WMState, WMTakeFocus, WMLast }; /* default atoms */
  66enum { ClkTagBar, ClkLtSymbol, ClkStatusText, ClkWinTitle,
  67       ClkClientWin, ClkRootWin, ClkLast };             /* clicks */
  68
  69typedef union {
  70	int i;
  71	unsigned int ui;
  72	float f;
  73	const void *v;
  74} Arg;
  75
  76typedef struct {
  77	unsigned int click;
  78	unsigned int mask;
  79	unsigned int button;
  80	void (*func)(const Arg *arg);
  81	const Arg arg;
  82} Button;
  83
  84typedef struct Monitor Monitor;
  85typedef struct Client Client;
  86struct Client {
  87	char name[256];
  88	float mina, maxa;
  89	int x, y, w, h;
  90	int oldx, oldy, oldw, oldh;
  91	int basew, baseh, incw, inch, maxw, maxh, minw, minh;
  92	int bw, oldbw;
  93	unsigned int tags;
  94	Bool isfixed, isfloating, isurgent, neverfocus, oldstate, isfullscreen;
  95	Client *next;
  96	Client *snext;
  97	Monitor *mon;
  98	Window win;
  99};
 100
 101typedef struct {
 102	unsigned int mod;
 103	KeySym keysym;
 104	void (*func)(const Arg *);
 105	const Arg arg;
 106} Key;
 107
 108typedef struct {
 109	const char *symbol;
 110	void (*arrange)(Monitor *);
 111} Layout;
 112
 113struct Monitor {
 114	char ltsymbol[16];
 115	float mfact;
 116	int nmaster;
 117	int num;
 118	int by;               /* bar geometry */
 119	int mx, my, mw, mh;   /* screen size */
 120	int wx, wy, ww, wh;   /* window area  */
 121	unsigned int seltags;
 122	unsigned int sellt;
 123	unsigned int tagset[2];
 124	Bool showbar;
 125	Bool topbar;
 126	Client *clients;
 127	Client *sel;
 128	Client *stack;
 129	Monitor *next;
 130	Window barwin;
 131	const Layout *lt[2];
 132};
 133
 134typedef struct {
 135	const char *class;
 136	const char *instance;
 137	const char *title;
 138	unsigned int tags;
 139	Bool isfloating;
 140	int monitor;
 141} Rule;
 142
 143/* function declarations */
 144static void applyrules(Client *c);
 145static Bool applysizehints(Client *c, int *x, int *y, int *w, int *h, Bool interact);
 146static void arrange(Monitor *m);
 147static void arrangemon(Monitor *m);
 148static void attach(Client *c);
 149static void attachstack(Client *c);
 150static void buttonpress(XEvent *e);
 151static void checkotherwm(void);
 152static void cleanup(void);
 153static void cleanupmon(Monitor *mon);
 154static void clearurgent(Client *c);
 155static void clientmessage(XEvent *e);
 156static void configure(Client *c);
 157static void configurenotify(XEvent *e);
 158static void configurerequest(XEvent *e);
 159static Monitor *createmon(void);
 160static void destroynotify(XEvent *e);
 161static void detach(Client *c);
 162static void detachstack(Client *c);
 163static Monitor *dirtomon(int dir);
 164static void drawbar(Monitor *m);
 165static void drawbars(void);
 166static void enternotify(XEvent *e);
 167static void expose(XEvent *e);
 168static void focus(Client *c);
 169static void focusin(XEvent *e);
 170static void focusmon(const Arg *arg);
 171static void focusstack(const Arg *arg);
 172static Bool getrootptr(int *x, int *y);
 173static long getstate(Window w);
 174static Bool gettextprop(Window w, Atom atom, char *text, unsigned int size);
 175static void grabbuttons(Client *c, Bool focused);
 176static void grabkeys(void);
 177static void incnmaster(const Arg *arg);
 178static void keypress(XEvent *e);
 179static void killclient(const Arg *arg);
 180static void manage(Window w, XWindowAttributes *wa);
 181static void mappingnotify(XEvent *e);
 182static void maprequest(XEvent *e);
 183static void monocle(Monitor *m);
 184static void motionnotify(XEvent *e);
 185static void movemouse(const Arg *arg);
 186static Client *nexttiled(Client *c);
 187static void pop(Client *);
 188static void propertynotify(XEvent *e);
 189static void quit(const Arg *arg);
 190static Monitor *recttomon(int x, int y, int w, int h);
 191static void resize(Client *c, int x, int y, int w, int h, Bool interact);
 192static void resizeclient(Client *c, int x, int y, int w, int h);
 193static void resizemouse(const Arg *arg);
 194static void restack(Monitor *m);
 195static void run(void);
 196static void scan(void);
 197static Bool sendevent(Client *c, Atom proto);
 198static void sendmon(Client *c, Monitor *m);
 199static void setclientstate(Client *c, long state);
 200static void setfocus(Client *c);
 201static void setfullscreen(Client *c, Bool fullscreen);
 202static void setlayout(const Arg *arg);
 203static void setmfact(const Arg *arg);
 204static void setup(void);
 205static void showhide(Client *c);
 206static void sigchld(int unused);
 207static void spawn(const Arg *arg);
 208static void tag(const Arg *arg);
 209static void tagmon(const Arg *arg);
 210static void tile(Monitor *);
 211static void togglebar(const Arg *arg);
 212static void togglefloating(const Arg *arg);
 213static void toggletag(const Arg *arg);
 214static void toggleview(const Arg *arg);
 215static void unfocus(Client *c, Bool setfocus);
 216static void unmanage(Client *c, Bool destroyed);
 217static void unmapnotify(XEvent *e);
 218static Bool updategeom(void);
 219static void updatebarpos(Monitor *m);
 220static void updatebars(void);
 221static void updateclientlist(void);
 222static void updatenumlockmask(void);
 223static void updatesizehints(Client *c);
 224static void updatestatus(void);
 225static void updatewindowtype(Client *c);
 226static void updatetitle(Client *c);
 227static void updatewmhints(Client *c);
 228static void view(const Arg *arg);
 229static Client *wintoclient(Window w);
 230static Monitor *wintomon(Window w);
 231static int xerror(Display *dpy, XErrorEvent *ee);
 232static int xerrordummy(Display *dpy, XErrorEvent *ee);
 233static int xerrorstart(Display *dpy, XErrorEvent *ee);
 234static void zoom(const Arg *arg);
 235
 236/* variables */
 237static const char broken[] = "broken";
 238static char stext[256];
 239static int screen;
 240static int sw, sh;           /* X display screen geometry width, height */
 241static int bh, blw = 0;      /* bar geometry */
 242static int (*xerrorxlib)(Display *, XErrorEvent *);
 243static unsigned int numlockmask = 0;
 244static void (*handler[LASTEvent]) (XEvent *) = {
 245	[ButtonPress] = buttonpress,
 246	[ClientMessage] = clientmessage,
 247	[ConfigureRequest] = configurerequest,
 248	[ConfigureNotify] = configurenotify,
 249	[DestroyNotify] = destroynotify,
 250	[EnterNotify] = enternotify,
 251	[Expose] = expose,
 252	[FocusIn] = focusin,
 253	[KeyPress] = keypress,
 254	[MappingNotify] = mappingnotify,
 255	[MapRequest] = maprequest,
 256	[MotionNotify] = motionnotify,
 257	[PropertyNotify] = propertynotify,
 258	[UnmapNotify] = unmapnotify
 259};
 260static Atom wmatom[WMLast], netatom[NetLast];
 261static Bool running = True;
 262static Cur *cursor[CurLast];
 263static Theme thmnorm[ColLast];
 264static Theme thmsel[ColLast];
 265static Display *dpy;
 266static Drw *drw;
 267static Fnt *fnt;
 268static Monitor *mons, *selmon;
 269static Window root;
 270
 271/* configuration, allows nested code to access above variables */
 272#include "config.h"
 273
 274/* compile-time check if all tags fit into an unsigned int bit array. */
 275struct NumTags { char limitexceeded[LENGTH(tags) > 31 ? -1 : 1]; };
 276
 277/* function implementations */
 278void
 279applyrules(Client *c) {
 280	const char *class, *instance;
 281	unsigned int i;
 282	const Rule *r;
 283	Monitor *m;
 284	XClassHint ch = { NULL, NULL };
 285
 286	/* rule matching */
 287	c->isfloating = c->tags = 0;
 288	XGetClassHint(dpy, c->win, &ch);
 289	class    = ch.res_class ? ch.res_class : broken;
 290	instance = ch.res_name  ? ch.res_name  : broken;
 291
 292	for(i = 0; i < LENGTH(rules); i++) {
 293		r = &rules[i];
 294		if((!r->title || strstr(c->name, r->title))
 295		&& (!r->class || strstr(class, r->class))
 296		&& (!r->instance || strstr(instance, r->instance)))
 297		{
 298			c->isfloating = r->isfloating;
 299			c->tags |= r->tags;
 300			for(m = mons; m && m->num != r->monitor; m = m->next);
 301			if(m)
 302				c->mon = m;
 303		}
 304	}
 305	if(ch.res_class)
 306		XFree(ch.res_class);
 307	if(ch.res_name)
 308		XFree(ch.res_name);
 309	c->tags = c->tags & TAGMASK ? c->tags & TAGMASK : c->mon->tagset[c->mon->seltags];
 310}
 311
 312Bool
 313applysizehints(Client *c, int *x, int *y, int *w, int *h, Bool interact) {
 314	Bool baseismin;
 315	Monitor *m = c->mon;
 316
 317	/* set minimum possible */
 318	*w = MAX(1, *w);
 319	*h = MAX(1, *h);
 320	if(interact) {
 321		if(*x > sw)
 322			*x = sw - WIDTH(c);
 323		if(*y > sh)
 324			*y = sh - HEIGHT(c);
 325		if(*x + *w + 2 * c->bw < 0)
 326			*x = 0;
 327		if(*y + *h + 2 * c->bw < 0)
 328			*y = 0;
 329	}
 330	else {
 331		if(*x >= m->wx + m->ww)
 332			*x = m->wx + m->ww - WIDTH(c);
 333		if(*y >= m->wy + m->wh)
 334			*y = m->wy + m->wh - HEIGHT(c);
 335		if(*x + *w + 2 * c->bw <= m->wx)
 336			*x = m->wx;
 337		if(*y + *h + 2 * c->bw <= m->wy)
 338			*y = m->wy;
 339	}
 340	if(*h < bh)
 341		*h = bh;
 342	if(*w < bh)
 343		*w = bh;
 344	if(resizehints || c->isfloating || !c->mon->lt[c->mon->sellt]->arrange) {
 345		/* see last two sentences in ICCCM 4.1.2.3 */
 346		baseismin = c->basew == c->minw && c->baseh == c->minh;
 347		if(!baseismin) { /* temporarily remove base dimensions */
 348			*w -= c->basew;
 349			*h -= c->baseh;
 350		}
 351		/* adjust for aspect limits */
 352		if(c->mina > 0 && c->maxa > 0) {
 353			if(c->maxa < (float)*w / *h)
 354				*w = *h * c->maxa + 0.5;
 355			else if(c->mina < (float)*h / *w)
 356				*h = *w * c->mina + 0.5;
 357		}
 358		if(baseismin) { /* increment calculation requires this */
 359			*w -= c->basew;
 360			*h -= c->baseh;
 361		}
 362		/* adjust for increment value */
 363		if(c->incw)
 364			*w -= *w % c->incw;
 365		if(c->inch)
 366			*h -= *h % c->inch;
 367		/* restore base dimensions */
 368		*w = MAX(*w + c->basew, c->minw);
 369		*h = MAX(*h + c->baseh, c->minh);
 370		if(c->maxw)
 371			*w = MIN(*w, c->maxw);
 372		if(c->maxh)
 373			*h = MIN(*h, c->maxh);
 374	}
 375	return *x != c->x || *y != c->y || *w != c->w || *h != c->h;
 376}
 377
 378void
 379arrange(Monitor *m) {
 380	if(m)
 381		showhide(m->stack);
 382	else for(m = mons; m; m = m->next)
 383		showhide(m->stack);
 384	if(m) {
 385		arrangemon(m);
 386		restack(m);
 387	} else for(m = mons; m; m = m->next)
 388		arrangemon(m);
 389}
 390
 391void
 392arrangemon(Monitor *m) {
 393	strncpy(m->ltsymbol, m->lt[m->sellt]->symbol, sizeof m->ltsymbol);
 394	if(m->lt[m->sellt]->arrange)
 395		m->lt[m->sellt]->arrange(m);
 396}
 397
 398void
 399attach(Client *c) {
 400	c->next = c->mon->clients;
 401	c->mon->clients = c;
 402}
 403
 404void
 405attachstack(Client *c) {
 406	c->snext = c->mon->stack;
 407	c->mon->stack = c;
 408}
 409
 410void
 411buttonpress(XEvent *e) {
 412	unsigned int i, x, click;
 413	Arg arg = {0};
 414	Client *c;
 415	Monitor *m;
 416	XButtonPressedEvent *ev = &e->xbutton;
 417
 418	click = ClkRootWin;
 419	/* focus monitor if necessary */
 420	if((m = wintomon(ev->window)) && m != selmon) {
 421		unfocus(selmon->sel, True);
 422		selmon = m;
 423		focus(NULL);
 424	}
 425	if(ev->window == selmon->barwin) {
 426		i = x = 0;
 427		do
 428			x += TEXTW(tags[i]);
 429		while(ev->x >= x && ++i < LENGTH(tags));
 430		if(i < LENGTH(tags)) {
 431			click = ClkTagBar;
 432			arg.ui = 1 << i;
 433		}
 434		else if(ev->x < x + blw)
 435			click = ClkLtSymbol;
 436		else if(ev->x > selmon->ww - TEXTW(stext))
 437			click = ClkStatusText;
 438		else
 439			click = ClkWinTitle;
 440	}
 441	else if((c = wintoclient(ev->window))) {
 442		focus(c);
 443		click = ClkClientWin;
 444	}
 445	for(i = 0; i < LENGTH(buttons); i++)
 446		if(click == buttons[i].click && buttons[i].func && buttons[i].button == ev->button
 447		&& CLEANMASK(buttons[i].mask) == CLEANMASK(ev->state))
 448			buttons[i].func(click == ClkTagBar && buttons[i].arg.i == 0 ? &arg : &buttons[i].arg);
 449}
 450
 451void
 452checkotherwm(void) {
 453	xerrorxlib = XSetErrorHandler(xerrorstart);
 454	/* this causes an error if some other window manager is running */
 455	XSelectInput(dpy, DefaultRootWindow(dpy), SubstructureRedirectMask);
 456	XSync(dpy, False);
 457	XSetErrorHandler(xerror);
 458	XSync(dpy, False);
 459}
 460
 461void
 462cleanup(void) {
 463	Arg a = {.ui = ~0};
 464	Layout foo = { "", NULL };
 465	Monitor *m;
 466
 467	view(&a);
 468	selmon->lt[selmon->sellt] = &foo;
 469	for(m = mons; m; m = m->next)
 470		while(m->stack)
 471			unmanage(m->stack, False);
 472	XUngrabKey(dpy, AnyKey, AnyModifier, root);
 473	while(mons)
 474		cleanupmon(mons);
 475	drw_cur_free(drw, cursor[CurNormal]);
 476	drw_cur_free(drw, cursor[CurResize]);
 477	drw_cur_free(drw, cursor[CurMove]);
 478	drw_font_free(dpy, fnt);
 479	drw_clr_free(thmnorm->border);
 480	drw_clr_free(thmnorm->bg);
 481	drw_clr_free(thmnorm->fg);
 482	drw_clr_free(thmsel->border);
 483	drw_clr_free(thmsel->bg);
 484	drw_clr_free(thmsel->fg);
 485	drw_free(drw);
 486	XSync(dpy, False);
 487	XSetInputFocus(dpy, PointerRoot, RevertToPointerRoot, CurrentTime);
 488	XDeleteProperty(dpy, root, netatom[NetActiveWindow]);
 489}
 490
 491void
 492cleanupmon(Monitor *mon) {
 493	Monitor *m;
 494
 495	if(mon == mons)
 496		mons = mons->next;
 497	else {
 498		for(m = mons; m && m->next != mon; m = m->next);
 499		m->next = mon->next;
 500	}
 501	XUnmapWindow(dpy, mon->barwin);
 502	XDestroyWindow(dpy, mon->barwin);
 503	free(mon);
 504}
 505
 506void
 507clearurgent(Client *c) {
 508	XWMHints *wmh;
 509
 510	c->isurgent = False;
 511	if(!(wmh = XGetWMHints(dpy, c->win)))
 512		return;
 513	wmh->flags &= ~XUrgencyHint;
 514	XSetWMHints(dpy, c->win, wmh);
 515	XFree(wmh);
 516}
 517
 518void
 519clientmessage(XEvent *e) {
 520	XClientMessageEvent *cme = &e->xclient;
 521	Client *c = wintoclient(cme->window);
 522
 523	if(!c)
 524		return;
 525	if(cme->message_type == netatom[NetWMState]) {
 526		if(cme->data.l[1] == netatom[NetWMFullscreen] || cme->data.l[2] == netatom[NetWMFullscreen])
 527			setfullscreen(c, (cme->data.l[0] == 1 /* _NET_WM_STATE_ADD    */
 528			              || (cme->data.l[0] == 2 /* _NET_WM_STATE_TOGGLE */ && !c->isfullscreen)));
 529	}
 530	else if(cme->message_type == netatom[NetActiveWindow]) {
 531		if(!ISVISIBLE(c)) {
 532			c->mon->seltags ^= 1;
 533			c->mon->tagset[c->mon->seltags] = c->tags;
 534		}
 535		pop(c);
 536	}
 537}
 538
 539void
 540configure(Client *c) {
 541	XConfigureEvent ce;
 542
 543	ce.type = ConfigureNotify;
 544	ce.display = dpy;
 545	ce.event = c->win;
 546	ce.window = c->win;
 547	ce.x = c->x;
 548	ce.y = c->y;
 549	ce.width = c->w;
 550	ce.height = c->h;
 551	ce.border_width = c->bw;
 552	ce.above = None;
 553	ce.override_redirect = False;
 554	XSendEvent(dpy, c->win, False, StructureNotifyMask, (XEvent *)&ce);
 555}
 556
 557void
 558configurenotify(XEvent *e) {
 559	Monitor *m;
 560	XConfigureEvent *ev = &e->xconfigure;
 561	Bool dirty;
 562
 563	// TODO: updategeom handling sucks, needs to be simplified
 564	if(ev->window == root) {
 565		dirty = (sw != ev->width || sh != ev->height);
 566		sw = ev->width;
 567		sh = ev->height;
 568		if(updategeom() || dirty) {
 569			drw_resize(drw, sw, bh);
 570			updatebars();
 571			for(m = mons; m; m = m->next)
 572				XMoveResizeWindow(dpy, m->barwin, m->wx, m->by, m->ww, bh);
 573			focus(NULL);
 574			arrange(NULL);
 575		}
 576	}
 577}
 578
 579void
 580configurerequest(XEvent *e) {
 581	Client *c;
 582	Monitor *m;
 583	XConfigureRequestEvent *ev = &e->xconfigurerequest;
 584	XWindowChanges wc;
 585
 586	if((c = wintoclient(ev->window))) {
 587		if(ev->value_mask & CWBorderWidth)
 588			c->bw = ev->border_width;
 589		else if(c->isfloating || !selmon->lt[selmon->sellt]->arrange) {
 590			m = c->mon;
 591			if(ev->value_mask & CWX) {
 592				c->oldx = c->x;
 593				c->x = m->mx + ev->x;
 594			}
 595			if(ev->value_mask & CWY) {
 596				c->oldy = c->y;
 597				c->y = m->my + ev->y;
 598			}
 599			if(ev->value_mask & CWWidth) {
 600				c->oldw = c->w;
 601				c->w = ev->width;
 602			}
 603			if(ev->value_mask & CWHeight) {
 604				c->oldh = c->h;
 605				c->h = ev->height;
 606			}
 607			if((c->x + c->w) > m->mx + m->mw && c->isfloating)
 608				c->x = m->mx + (m->mw / 2 - WIDTH(c) / 2); /* center in x direction */
 609			if((c->y + c->h) > m->my + m->mh && c->isfloating)
 610				c->y = m->my + (m->mh / 2 - HEIGHT(c) / 2); /* center in y direction */
 611			if((ev->value_mask & (CWX|CWY)) && !(ev->value_mask & (CWWidth|CWHeight)))
 612				configure(c);
 613			if(ISVISIBLE(c))
 614				XMoveResizeWindow(dpy, c->win, c->x, c->y, c->w, c->h);
 615		}
 616		else
 617			configure(c);
 618	}
 619	else {
 620		wc.x = ev->x;
 621		wc.y = ev->y;
 622		wc.width = ev->width;
 623		wc.height = ev->height;
 624		wc.border_width = ev->border_width;
 625		wc.sibling = ev->above;
 626		wc.stack_mode = ev->detail;
 627		XConfigureWindow(dpy, ev->window, ev->value_mask, &wc);
 628	}
 629	XSync(dpy, False);
 630}
 631
 632Monitor *
 633createmon(void) {
 634	Monitor *m;
 635
 636	if(!(m = (Monitor *)calloc(1, sizeof(Monitor))))
 637		die("fatal: could not malloc() %u bytes\n", sizeof(Monitor));
 638	m->tagset[0] = m->tagset[1] = 1;
 639	m->mfact = mfact;
 640	m->nmaster = nmaster;
 641	m->showbar = showbar;
 642	m->topbar = topbar;
 643	m->lt[0] = &layouts[0];
 644	m->lt[1] = &layouts[1 % LENGTH(layouts)];
 645	strncpy(m->ltsymbol, layouts[0].symbol, sizeof m->ltsymbol);
 646	return m;
 647}
 648
 649void
 650destroynotify(XEvent *e) {
 651	Client *c;
 652	XDestroyWindowEvent *ev = &e->xdestroywindow;
 653
 654	if((c = wintoclient(ev->window)))
 655		unmanage(c, True);
 656}
 657
 658void
 659detach(Client *c) {
 660	Client **tc;
 661
 662	for(tc = &c->mon->clients; *tc && *tc != c; tc = &(*tc)->next);
 663	*tc = c->next;
 664}
 665
 666void
 667detachstack(Client *c) {
 668	Client **tc, *t;
 669
 670	for(tc = &c->mon->stack; *tc && *tc != c; tc = &(*tc)->snext);
 671	*tc = c->snext;
 672
 673	if(c == c->mon->sel) {
 674		for(t = c->mon->stack; t && !ISVISIBLE(t); t = t->snext);
 675		c->mon->sel = t;
 676	}
 677}
 678
 679Monitor *
 680dirtomon(int dir) {
 681	Monitor *m = NULL;
 682
 683	if(dir > 0) {
 684		if(!(m = selmon->next))
 685			m = mons;
 686	}
 687	else if(selmon == mons)
 688		for(m = mons; m->next; m = m->next);
 689	else
 690		for(m = mons; m->next != selmon; m = m->next);
 691	return m;
 692}
 693
 694void
 695drawbar(Monitor *m) {
 696	int x, xx, w;
 697	unsigned int i, occ = 0, urg = 0;
 698	Client *c;
 699
 700	for(c = m->clients; c; c = c->next) {
 701		occ |= c->tags;
 702		if(c->isurgent)
 703			urg |= c->tags;
 704	}
 705	x = 0;
 706	for(i = 0; i < LENGTH(tags); i++) {
 707		w = TEXTW(tags[i]);
 708		drw_settheme(drw, m->tagset[m->seltags] & 1 << i ? thmsel : thmnorm);
 709		drw_text(drw, x, 0, w, bh, tags[i], urg & 1 << i);
 710		drw_rect(drw, x, 0, w, bh, m == selmon && selmon->sel && selmon->sel->tags & 1 << i,
 711		           occ & 1 << i, urg & 1 << i);
 712		x += w;
 713	}
 714	w = blw = TEXTW(m->ltsymbol);
 715	drw_settheme(drw, thmnorm);
 716	drw_text(drw, x, 0, w, bh, m->ltsymbol, 0);
 717	x += w;
 718	xx = x;
 719	if(m == selmon) { /* status is only drawn on selected monitor */
 720		w = TEXTW(stext);
 721		x = m->ww - w;
 722		if(x < xx) {
 723			x = xx;
 724			w = m->ww - xx;
 725		}
 726		drw_text(drw, x, 0, w, bh, stext, 0);
 727	}
 728	else
 729		x = m->ww;
 730	if((w = x - xx) > bh) {
 731		x = xx;
 732		if(m->sel) {
 733			drw_settheme(drw, m == selmon ? thmsel : thmnorm);
 734			drw_text(drw, x, 0, w, bh, m->sel->name, 0);
 735			drw_rect(drw, x, 0, w, bh, m->sel->isfixed, m->sel->isfloating, 0);
 736		}
 737		else {
 738			drw_settheme(drw, thmnorm);
 739			drw_text(drw, x, 0, w, bh, NULL, 0);
 740		}
 741	}
 742	drw_map(drw, m->barwin, 0, 0, m->ww, bh);
 743}
 744
 745void
 746drawbars(void) {
 747	Monitor *m;
 748
 749	for(m = mons; m; m = m->next)
 750		drawbar(m);
 751}
 752
 753void
 754enternotify(XEvent *e) {
 755	Client *c;
 756	Monitor *m;
 757	XCrossingEvent *ev = &e->xcrossing;
 758
 759	if((ev->mode != NotifyNormal || ev->detail == NotifyInferior) && ev->window != root)
 760		return;
 761	c = wintoclient(ev->window);
 762	m = c ? c->mon : wintomon(ev->window);
 763	if(m != selmon) {
 764		unfocus(selmon->sel, True);
 765		selmon = m;
 766	}
 767	else if(!c || c == selmon->sel)
 768		return;
 769	focus(c);
 770}
 771
 772void
 773expose(XEvent *e) {
 774	Monitor *m;
 775	XExposeEvent *ev = &e->xexpose;
 776
 777	if(ev->count == 0 && (m = wintomon(ev->window)))
 778		drawbar(m);
 779}
 780
 781void
 782focus(Client *c) {
 783	if(!c || !ISVISIBLE(c))
 784		for(c = selmon->stack; c && !ISVISIBLE(c); c = c->snext);
 785	/* was if(selmon->sel) */
 786	if(selmon->sel && selmon->sel != c)
 787		unfocus(selmon->sel, False);
 788	if(c) {
 789		if(c->mon != selmon)
 790			selmon = c->mon;
 791		if(c->isurgent)
 792			clearurgent(c);
 793		detachstack(c);
 794		attachstack(c);
 795		grabbuttons(c, True);
 796		XSetWindowBorder(dpy, c->win, thmsel->border->rgb);
 797		setfocus(c);
 798	}
 799	else {
 800		XSetInputFocus(dpy, root, RevertToPointerRoot, CurrentTime);
 801		XDeleteProperty(dpy, root, netatom[NetActiveWindow]);
 802	}
 803	selmon->sel = c;
 804	drawbars();
 805}
 806
 807void
 808focusin(XEvent *e) { /* there are some broken focus acquiring clients */
 809	XFocusChangeEvent *ev = &e->xfocus;
 810
 811	if(selmon->sel && ev->window != selmon->sel->win)
 812		setfocus(selmon->sel);
 813}
 814
 815void
 816focusmon(const Arg *arg) {
 817	Monitor *m;
 818
 819	if(!mons->next)
 820		return;
 821	if((m = dirtomon(arg->i)) == selmon)
 822		return;
 823	unfocus(selmon->sel, False); /* s/True/False/ fixes input focus issues
 824					in gedit and anjuta */
 825	selmon = m;
 826	focus(NULL);
 827}
 828
 829void
 830focusstack(const Arg *arg) {
 831	Client *c = NULL, *i;
 832
 833	if(!selmon->sel)
 834		return;
 835	if(arg->i > 0) {
 836		for(c = selmon->sel->next; c && !ISVISIBLE(c); c = c->next);
 837		if(!c)
 838			for(c = selmon->clients; c && !ISVISIBLE(c); c = c->next);
 839	}
 840	else {
 841		for(i = selmon->clients; i != selmon->sel; i = i->next)
 842			if(ISVISIBLE(i))
 843				c = i;
 844		if(!c)
 845			for(; i; i = i->next)
 846				if(ISVISIBLE(i))
 847					c = i;
 848	}
 849	if(c) {
 850		focus(c);
 851		restack(selmon);
 852	}
 853}
 854
 855Atom
 856getatomprop(Client *c, Atom prop) {
 857	int di;
 858	unsigned long dl;
 859	unsigned char *p = NULL;
 860	Atom da, atom = None;
 861
 862	if(XGetWindowProperty(dpy, c->win, prop, 0L, sizeof atom, False, XA_ATOM,
 863	                      &da, &di, &dl, &dl, &p) == Success && p) {
 864		atom = *(Atom *)p;
 865		XFree(p);
 866	}
 867	return atom;
 868}
 869
 870Bool
 871getrootptr(int *x, int *y) {
 872	int di;
 873	unsigned int dui;
 874	Window dummy;
 875
 876	return XQueryPointer(dpy, root, &dummy, &dummy, x, y, &di, &di, &dui);
 877}
 878
 879long
 880getstate(Window w) {
 881	int format;
 882	long result = -1;
 883	unsigned char *p = NULL;
 884	unsigned long n, extra;
 885	Atom real;
 886
 887	if(XGetWindowProperty(dpy, w, wmatom[WMState], 0L, 2L, False, wmatom[WMState],
 888	                      &real, &format, &n, &extra, (unsigned char **)&p) != Success)
 889		return -1;
 890	if(n != 0)
 891		result = *p;
 892	XFree(p);
 893	return result;
 894}
 895
 896Bool
 897gettextprop(Window w, Atom atom, char *text, unsigned int size) {
 898	char **list = NULL;
 899	int n;
 900	XTextProperty name;
 901
 902	if(!text || size == 0)
 903		return False;
 904	text[0] = '\0';
 905	XGetTextProperty(dpy, w, &name, atom);
 906	if(!name.nitems)
 907		return False;
 908	if(name.encoding == XA_STRING)
 909		strncpy(text, (char *)name.value, size - 1);
 910	else {
 911		if(XmbTextPropertyToTextList(dpy, &name, &list, &n) >= Success && n > 0 && *list) {
 912			strncpy(text, *list, size - 1);
 913			XFreeStringList(list);
 914		}
 915	}
 916	text[size - 1] = '\0';
 917	XFree(name.value);
 918	return True;
 919}
 920
 921void
 922grabbuttons(Client *c, Bool focused) {
 923	updatenumlockmask();
 924	{
 925		unsigned int i, j;
 926		unsigned int modifiers[] = { 0, LockMask, numlockmask, numlockmask|LockMask };
 927		XUngrabButton(dpy, AnyButton, AnyModifier, c->win);
 928		if(focused) {
 929			for(i = 0; i < LENGTH(buttons); i++)
 930				if(buttons[i].click == ClkClientWin)
 931					for(j = 0; j < LENGTH(modifiers); j++)
 932						XGrabButton(dpy, buttons[i].button,
 933						            buttons[i].mask | modifiers[j],
 934						            c->win, False, BUTTONMASK,
 935						            GrabModeAsync, GrabModeSync, None, None);
 936		}
 937		else
 938			XGrabButton(dpy, AnyButton, AnyModifier, c->win, False,
 939			            BUTTONMASK, GrabModeAsync, GrabModeSync, None, None);
 940	}
 941}
 942
 943void
 944grabkeys(void) {
 945	updatenumlockmask();
 946	{
 947		unsigned int i, j;
 948		unsigned int modifiers[] = { 0, LockMask, numlockmask, numlockmask|LockMask };
 949		KeyCode code;
 950
 951		XUngrabKey(dpy, AnyKey, AnyModifier, root);
 952		for(i = 0; i < LENGTH(keys); i++)
 953			if((code = XKeysymToKeycode(dpy, keys[i].keysym)))
 954				for(j = 0; j < LENGTH(modifiers); j++)
 955					XGrabKey(dpy, code, keys[i].mod | modifiers[j], root,
 956						 True, GrabModeAsync, GrabModeAsync);
 957	}
 958}
 959
 960void
 961incnmaster(const Arg *arg) {
 962	selmon->nmaster = MAX(selmon->nmaster + arg->i, 0);
 963	arrange(selmon);
 964}
 965
 966#ifdef XINERAMA
 967static Bool
 968isuniquegeom(XineramaScreenInfo *unique, size_t n, XineramaScreenInfo *info) {
 969	while(n--)
 970		if(unique[n].x_org == info->x_org && unique[n].y_org == info->y_org
 971		&& unique[n].width == info->width && unique[n].height == info->height)
 972			return False;
 973	return True;
 974}
 975#endif /* XINERAMA */
 976
 977void
 978keypress(XEvent *e) {
 979	unsigned int i;
 980	KeySym keysym;
 981	XKeyEvent *ev;
 982
 983	ev = &e->xkey;
 984	keysym = XKeycodeToKeysym(dpy, (KeyCode)ev->keycode, 0);
 985	for(i = 0; i < LENGTH(keys); i++)
 986		if(keysym == keys[i].keysym
 987		&& CLEANMASK(keys[i].mod) == CLEANMASK(ev->state)
 988		&& keys[i].func)
 989			keys[i].func(&(keys[i].arg));
 990}
 991
 992void
 993killclient(const Arg *arg) {
 994	if(!selmon->sel)
 995		return;
 996	if(!sendevent(selmon->sel, wmatom[WMDelete])) {
 997		XGrabServer(dpy);
 998		XSetErrorHandler(xerrordummy);
 999		XSetCloseDownMode(dpy, DestroyAll);
1000		XKillClient(dpy, selmon->sel->win);
1001		XSync(dpy, False);
1002		XSetErrorHandler(xerror);
1003		XUngrabServer(dpy);
1004	}
1005}
1006
1007void
1008manage(Window w, XWindowAttributes *wa) {
1009	Client *c, *t = NULL;
1010	Window trans = None;
1011	XWindowChanges wc;
1012
1013	if(!(c = calloc(1, sizeof(Client))))
1014		die("fatal: could not malloc() %u bytes\n", sizeof(Client));
1015	c->win = w;
1016	updatetitle(c);
1017	if(XGetTransientForHint(dpy, w, &trans) && (t = wintoclient(trans))) {
1018		c->mon = t->mon;
1019		c->tags = t->tags;
1020	}
1021	else {
1022		c->mon = selmon;
1023		applyrules(c);
1024	}
1025	/* geometry */
1026	c->x = c->oldx = wa->x;
1027	c->y = c->oldy = wa->y;
1028	c->w = c->oldw = wa->width;
1029	c->h = c->oldh = wa->height;
1030	c->oldbw = wa->border_width;
1031
1032	if(c->x + WIDTH(c) > c->mon->mx + c->mon->mw)
1033		c->x = c->mon->mx + c->mon->mw - WIDTH(c);
1034	if(c->y + HEIGHT(c) > c->mon->my + c->mon->mh)
1035		c->y = c->mon->my + c->mon->mh - HEIGHT(c);
1036	c->x = MAX(c->x, c->mon->mx);
1037	/* only fix client y-offset, if the client center might cover the bar */
1038	c->y = MAX(c->y, ((c->mon->by == c->mon->my) && (c->x + (c->w / 2) >= c->mon->wx)
1039	           && (c->x + (c->w / 2) < c->mon->wx + c->mon->ww)) ? bh : c->mon->my);
1040	c->bw = borderpx;
1041
1042	wc.border_width = c->bw;
1043	XConfigureWindow(dpy, w, CWBorderWidth, &wc);
1044	XSetWindowBorder(dpy, w, thmnorm->border->rgb);
1045	configure(c); /* propagates border_width, if size doesn't change */
1046	updatewindowtype(c);
1047	updatesizehints(c);
1048	updatewmhints(c);
1049	XSelectInput(dpy, w, EnterWindowMask|FocusChangeMask|PropertyChangeMask|StructureNotifyMask);
1050	grabbuttons(c, False);
1051	if(!c->isfloating)
1052		c->isfloating = c->oldstate = trans != None || c->isfixed;
1053	if(c->isfloating)
1054		XRaiseWindow(dpy, c->win);
1055	attach(c);
1056	attachstack(c);
1057	XChangeProperty(dpy, root, netatom[NetClientList], XA_WINDOW, 32, PropModeAppend,
1058	                (unsigned char *) &(c->win), 1);
1059	XMoveResizeWindow(dpy, c->win, c->x + 2 * sw, c->y, c->w, c->h); /* some windows require this */
1060	setclientstate(c, NormalState);
1061	if (c->mon == selmon)
1062		unfocus(selmon->sel, False);
1063	c->mon->sel = c;
1064	arrange(c->mon);
1065	XMapWindow(dpy, c->win);
1066	focus(NULL);
1067}
1068
1069void
1070mappingnotify(XEvent *e) {
1071	XMappingEvent *ev = &e->xmapping;
1072
1073	XRefreshKeyboardMapping(ev);
1074	if(ev->request == MappingKeyboard)
1075		grabkeys();
1076}
1077
1078void
1079maprequest(XEvent *e) {
1080	static XWindowAttributes wa;
1081	XMapRequestEvent *ev = &e->xmaprequest;
1082
1083	if(!XGetWindowAttributes(dpy, ev->window, &wa))
1084		return;
1085	if(wa.override_redirect)
1086		return;
1087	if(!wintoclient(ev->window))
1088		manage(ev->window, &wa);
1089}
1090
1091void
1092monocle(Monitor *m) {
1093	unsigned int n = 0;
1094	Client *c;
1095
1096	for(c = m->clients; c; c = c->next)
1097		if(ISVISIBLE(c))
1098			n++;
1099	if(n > 0) /* override layout symbol */
1100		snprintf(m->ltsymbol, sizeof m->ltsymbol, "[%d]", n);
1101	for(c = nexttiled(m->clients); c; c = nexttiled(c->next))
1102		resize(c, m->wx, m->wy, m->ww - 2 * c->bw, m->wh - 2 * c->bw, False);
1103}
1104
1105void
1106motionnotify(XEvent *e) {
1107	static Monitor *mon = NULL;
1108	Monitor *m;
1109	XMotionEvent *ev = &e->xmotion;
1110
1111	if(ev->window != root)
1112		return;
1113	if((m = recttomon(ev->x_root, ev->y_root, 1, 1)) != mon && mon) {
1114		unfocus(selmon->sel, True);
1115		selmon = m;
1116		focus(NULL);
1117	}
1118	mon = m;
1119}
1120
1121void
1122movemouse(const Arg *arg) {
1123	int x, y, ocx, ocy, nx, ny;
1124	Client *c;
1125	Monitor *m;
1126	XEvent ev;
1127
1128	if(!(c = selmon->sel))
1129		return;
1130	if(c->isfullscreen) /* no support moving fullscreen windows by mouse */
1131		return;
1132	restack(selmon);
1133	ocx = c->x;
1134	ocy = c->y;
1135	if(XGrabPointer(dpy, root, False, MOUSEMASK, GrabModeAsync, GrabModeAsync,
1136	None, cursor[CurMove]->cursor, CurrentTime) != GrabSuccess)
1137		return;
1138	if(!getrootptr(&x, &y))
1139		return;
1140	do {
1141		XMaskEvent(dpy, MOUSEMASK|ExposureMask|SubstructureRedirectMask, &ev);
1142		switch(ev.type) {
1143		case ConfigureRequest:
1144		case Expose:
1145		case MapRequest:
1146			handler[ev.type](&ev);
1147			break;
1148		case MotionNotify:
1149			nx = ocx + (ev.xmotion.x - x);
1150			ny = ocy + (ev.xmotion.y - y);
1151			if(nx >= selmon->wx && nx <= selmon->wx + selmon->ww
1152			&& ny >= selmon->wy && ny <= selmon->wy + selmon->wh) {
1153				if(abs(selmon->wx - nx) < snap)
1154					nx = selmon->wx;
1155				else if(abs((selmon->wx + selmon->ww) - (nx + WIDTH(c))) < snap)
1156					nx = selmon->wx + selmon->ww - WIDTH(c);
1157				if(abs(selmon->wy - ny) < snap)
1158					ny = selmon->wy;
1159				else if(abs((selmon->wy + selmon->wh) - (ny + HEIGHT(c))) < snap)
1160					ny = selmon->wy + selmon->wh - HEIGHT(c);
1161				if(!c->isfloating && selmon->lt[selmon->sellt]->arrange
1162				&& (abs(nx - c->x) > snap || abs(ny - c->y) > snap))
1163					togglefloating(NULL);
1164			}
1165			if(!selmon->lt[selmon->sellt]->arrange || c->isfloating)
1166				resize(c, nx, ny, c->w, c->h, True);
1167			break;
1168		}
1169	} while(ev.type != ButtonRelease);
1170	XUngrabPointer(dpy, CurrentTime);
1171	if((m = recttomon(c->x, c->y, c->w, c->h)) != selmon) {
1172		sendmon(c, m);
1173		selmon = m;
1174		focus(NULL);
1175	}
1176}
1177
1178Client *
1179nexttiled(Client *c) {
1180	for(; c && (c->isfloating || !ISVISIBLE(c)); c = c->next);
1181	return c;
1182}
1183
1184void
1185pop(Client *c) {
1186	detach(c);
1187	attach(c);
1188	focus(c);
1189	arrange(c->mon);
1190}
1191
1192void
1193propertynotify(XEvent *e) {
1194	Client *c;
1195	Window trans;
1196	XPropertyEvent *ev = &e->xproperty;
1197
1198	if((ev->window == root) && (ev->atom == XA_WM_NAME))
1199		updatestatus();
1200	else if(ev->state == PropertyDelete)
1201		return; /* ignore */
1202	else if((c = wintoclient(ev->window))) {
1203		switch(ev->atom) {
1204		default: break;
1205		case XA_WM_TRANSIENT_FOR:
1206			if(!c->isfloating && (XGetTransientForHint(dpy, c->win, &trans)) &&
1207			   (c->isfloating = (wintoclient(trans)) != NULL))
1208				arrange(c->mon);
1209			break;
1210		case XA_WM_NORMAL_HINTS:
1211			updatesizehints(c);
1212			break;
1213		case XA_WM_HINTS:
1214			updatewmhints(c);
1215			drawbars();
1216			break;
1217		}
1218		if(ev->atom == XA_WM_NAME || ev->atom == netatom[NetWMName]) {
1219			updatetitle(c);
1220			if(c == c->mon->sel)
1221				drawbar(c->mon);
1222		}
1223		if(ev->atom == netatom[NetWMWindowType])
1224			updatewindowtype(c);
1225	}
1226}
1227
1228void
1229quit(const Arg *arg) {
1230	running = False;
1231}
1232
1233Monitor *
1234recttomon(int x, int y, int w, int h) {
1235	Monitor *m, *r = selmon;
1236	int a, area = 0;
1237
1238	for(m = mons; m; m = m->next)
1239		if((a = INTERSECT(x, y, w, h, m)) > area) {
1240			area = a;
1241			r = m;
1242		}
1243	return r;
1244}
1245
1246void
1247resize(Client *c, int x, int y, int w, int h, Bool interact) {
1248	if(applysizehints(c, &x, &y, &w, &h, interact))
1249		resizeclient(c, x, y, w, h);
1250}
1251
1252void
1253resizeclient(Client *c, int x, int y, int w, int h) {
1254	XWindowChanges wc;
1255
1256	c->oldx = c->x; c->x = wc.x = x;
1257	c->oldy = c->y; c->y = wc.y = y;
1258	c->oldw = c->w; c->w = wc.width = w;
1259	c->oldh = c->h; c->h = wc.height = h;
1260	wc.border_width = c->bw;
1261	XConfigureWindow(dpy, c->win, CWX|CWY|CWWidth|CWHeight|CWBorderWidth, &wc);
1262	configure(c);
1263	XSync(dpy, False);
1264}
1265
1266void
1267resizemouse(const Arg *arg) {
1268	int ocx, ocy;
1269	int nw, nh;
1270	Client *c;
1271	Monitor *m;
1272	XEvent ev;
1273
1274	if(!(c = selmon->sel))
1275		return;
1276	if(c->isfullscreen) /* no support resizing fullscreen windows by mouse */
1277		return;
1278	restack(selmon);
1279	ocx = c->x;
1280	ocy = c->y;
1281	if(XGrabPointer(dpy, root, False, MOUSEMASK, GrabModeAsync, GrabModeAsync,
1282	                None, cursor[CurResize]->cursor, CurrentTime) != GrabSuccess)
1283		return;
1284	XWarpPointer(dpy, None, c->win, 0, 0, 0, 0, c->w + c->bw - 1, c->h + c->bw - 1);
1285	do {
1286		XMaskEvent(dpy, MOUSEMASK|ExposureMask|SubstructureRedirectMask, &ev);
1287		switch(ev.type) {
1288		case ConfigureRequest:
1289		case Expose:
1290		case MapRequest:
1291			handler[ev.type](&ev);
1292			break;
1293		case MotionNotify:
1294			nw = MAX(ev.xmotion.x - ocx - 2 * c->bw + 1, 1);
1295			nh = MAX(ev.xmotion.y - ocy - 2 * c->bw + 1, 1);
1296			if(c->mon->wx + nw >= selmon->wx && c->mon->wx + nw <= selmon->wx + selmon->ww
1297			&& c->mon->wy + nh >= selmon->wy && c->mon->wy + nh <= selmon->wy + selmon->wh)
1298			{
1299				if(!c->isfloating && selmon->lt[selmon->sellt]->arrange
1300				&& (abs(nw - c->w) > snap || abs(nh - c->h) > snap))
1301					togglefloating(NULL);
1302			}
1303			if(!selmon->lt[selmon->sellt]->arrange || c->isfloating)
1304				resize(c, c->x, c->y, nw, nh, True);
1305			break;
1306		}
1307	} while(ev.type != ButtonRelease);
1308	XWarpPointer(dpy, None, c->win, 0, 0, 0, 0, c->w + c->bw - 1, c->h + c->bw - 1);
1309	XUngrabPointer(dpy, CurrentTime);
1310	while(XCheckMaskEvent(dpy, EnterWindowMask, &ev));
1311	if((m = recttomon(c->x, c->y, c->w, c->h)) != selmon) {
1312		sendmon(c, m);
1313		selmon = m;
1314		focus(NULL);
1315	}
1316}
1317
1318void
1319restack(Monitor *m) {
1320	Client *c;
1321	XEvent ev;
1322	XWindowChanges wc;
1323
1324	drawbar(m);
1325	if(!m->sel)
1326		return;
1327	if(m->sel->isfloating || !m->lt[m->sellt]->arrange)
1328		XRaiseWindow(dpy, m->sel->win);
1329	if(m->lt[m->sellt]->arrange) {
1330		wc.stack_mode = Below;
1331		wc.sibling = m->barwin;
1332		for(c = m->stack; c; c = c->snext)
1333			if(!c->isfloating && ISVISIBLE(c)) {
1334				XConfigureWindow(dpy, c->win, CWSibling|CWStackMode, &wc);
1335				wc.sibling = c->win;
1336			}
1337	}
1338	XSync(dpy, False);
1339	while(XCheckMaskEvent(dpy, EnterWindowMask, &ev));
1340}
1341
1342void
1343run(void) {
1344	XEvent ev;
1345	/* main event loop */
1346	XSync(dpy, False);
1347	while(running && !XNextEvent(dpy, &ev))
1348		if(handler[ev.type])
1349			handler[ev.type](&ev); /* call handler */
1350}
1351
1352void
1353scan(void) {
1354	unsigned int i, num;
1355	Window d1, d2, *wins = NULL;
1356	XWindowAttributes wa;
1357
1358	if(XQueryTree(dpy, root, &d1, &d2, &wins, &num)) {
1359		for(i = 0; i < num; i++) {
1360			if(!XGetWindowAttributes(dpy, wins[i], &wa)
1361			|| wa.override_redirect || XGetTransientForHint(dpy, wins[i], &d1))
1362				continue;
1363			if(wa.map_state == IsViewable || getstate(wins[i]) == IconicState)
1364				manage(wins[i], &wa);
1365		}
1366		for(i = 0; i < num; i++) { /* now the transients */
1367			if(!XGetWindowAttributes(dpy, wins[i], &wa))
1368				continue;
1369			if(XGetTransientForHint(dpy, wins[i], &d1)
1370			&& (wa.map_state == IsViewable || getstate(wins[i]) == IconicState))
1371				manage(wins[i], &wa);
1372		}
1373		if(wins)
1374			XFree(wins);
1375	}
1376}
1377
1378void
1379sendmon(Client *c, Monitor *m) {
1380	if(c->mon == m)
1381		return;
1382	unfocus(c, True);
1383	detach(c);
1384	detachstack(c);
1385	c->mon = m;
1386	c->tags = m->tagset[m->seltags]; /* assign tags of target monitor */
1387	attach(c);
1388	attachstack(c);
1389	focus(NULL);
1390	arrange(NULL);
1391}
1392
1393void
1394setclientstate(Client *c, long state) {
1395	long data[] = { state, None };
1396
1397	XChangeProperty(dpy, c->win, wmatom[WMState], wmatom[WMState], 32,
1398			PropModeReplace, (unsigned char *)data, 2);
1399}
1400
1401Bool
1402sendevent(Client *c, Atom proto) {
1403	int n;
1404	Atom *protocols;
1405	Bool exists = False;
1406	XEvent ev;
1407
1408	if(XGetWMProtocols(dpy, c->win, &protocols, &n)) {
1409		while(!exists && n--)
1410			exists = protocols[n] == proto;
1411		XFree(protocols);
1412	}
1413	if(exists) {
1414		ev.type = ClientMessage;
1415		ev.xclient.window = c->win;
1416		ev.xclient.message_type = wmatom[WMProtocols];
1417		ev.xclient.format = 32;
1418		ev.xclient.data.l[0] = proto;
1419		ev.xclient.data.l[1] = CurrentTime;
1420		XSendEvent(dpy, c->win, False, NoEventMask, &ev);
1421	}
1422	return exists;
1423}
1424
1425void
1426setfocus(Client *c) {
1427	if(!c->neverfocus) {
1428		XSetInputFocus(dpy, c->win, RevertToPointerRoot, CurrentTime);
1429		XChangeProperty(dpy, root, netatom[NetActiveWindow],
1430 		                XA_WINDOW, 32, PropModeReplace,
1431 		                (unsigned char *) &(c->win), 1);
1432	}
1433	sendevent(c, wmatom[WMTakeFocus]);
1434}
1435
1436void
1437setfullscreen(Client *c, Bool fullscreen) {
1438	if(fullscreen) {
1439		XChangeProperty(dpy, c->win, netatom[NetWMState], XA_ATOM, 32,
1440		                PropModeReplace, (unsigned char*)&netatom[NetWMFullscreen], 1);
1441		c->isfullscreen = True;
1442		c->oldstate = c->isfloating;
1443		c->oldbw = c->bw;
1444		c->bw = 0;
1445		c->isfloating = True;
1446		resizeclient(c, c->mon->mx, c->mon->my, c->mon->mw, c->mon->mh);
1447		XRaiseWindow(dpy, c->win);
1448	}
1449	else {
1450		XChangeProperty(dpy, c->win, netatom[NetWMState], XA_ATOM, 32,
1451		                PropModeReplace, (unsigned char*)0, 0);
1452		c->isfullscreen = False;
1453		c->isfloating = c->oldstate;
1454		c->bw = c->oldbw;
1455		c->x = c->oldx;
1456		c->y = c->oldy;
1457		c->w = c->oldw;
1458		c->h = c->oldh;
1459		resizeclient(c, c->x, c->y, c->w, c->h);
1460		arrange(c->mon);
1461	}
1462}
1463
1464void
1465setlayout(const Arg *arg) {
1466	if(!arg || !arg->v || arg->v != selmon->lt[selmon->sellt])
1467		selmon->sellt ^= 1;
1468	if(arg && arg->v)
1469		selmon->lt[selmon->sellt] = (Layout *)arg->v;
1470	strncpy(selmon->ltsymbol, selmon->lt[selmon->sellt]->symbol, sizeof selmon->ltsymbol);
1471	if(selmon->sel)
1472		arrange(selmon);
1473	else
1474		drawbar(selmon);
1475}
1476
1477/* arg > 1.0 will set mfact absolutly */
1478void
1479setmfact(const Arg *arg) {
1480	float f;
1481
1482	if(!arg || !selmon->lt[selmon->sellt]->arrange)
1483		return;
1484	f = arg->f < 1.0 ? arg->f + selmon->mfact : arg->f - 1.0;
1485	if(f < 0.1 || f > 0.9)
1486		return;
1487	selmon->mfact = f;
1488	arrange(selmon);
1489}
1490
1491void
1492setup(void) {
1493	XSetWindowAttributes wa;
1494
1495	/* clean up any zombies immediately */
1496	sigchld(0);
1497
1498	/* init screen */
1499	screen = DefaultScreen(dpy);
1500	root = RootWindow(dpy, screen);
1501	fnt = drw_font_create(dpy, font);
1502	sw = DisplayWidth(dpy, screen);
1503	sh = DisplayHeight(dpy, screen);
1504	bh = fnt->h + 2;
1505	drw = drw_create(dpy, screen, root, sw, sh);
1506	drw_setfont(drw, fnt);
1507	updategeom();
1508	/* init atoms */
1509	wmatom[WMProtocols] = XInternAtom(dpy, "WM_PROTOCOLS", False);
1510	wmatom[WMDelete] = XInternAtom(dpy, "WM_DELETE_WINDOW", False);
1511	wmatom[WMState] = XInternAtom(dpy, "WM_STATE", False);
1512	wmatom[WMTakeFocus] = XInternAtom(dpy, "WM_TAKE_FOCUS", False);
1513	netatom[NetActiveWindow] = XInternAtom(dpy, "_NET_ACTIVE_WINDOW", False);
1514	netatom[NetSupported] = XInternAtom(dpy, "_NET_SUPPORTED", False);
1515	netatom[NetWMName] = XInternAtom(dpy, "_NET_WM_NAME", False);
1516	netatom[NetWMState] = XInternAtom(dpy, "_NET_WM_STATE", False);
1517	netatom[NetWMFullscreen] = XInternAtom(dpy, "_NET_WM_STATE_FULLSCREEN", False);
1518	netatom[NetWMWindowType] = XInternAtom(dpy, "_NET_WM_WINDOW_TYPE", False);
1519	netatom[NetWMWindowTypeDialog] = XInternAtom(dpy, "_NET_WM_WINDOW_TYPE_DIALOG", False);
1520	netatom[NetClientList] = XInternAtom(dpy, "_NET_CLIENT_LIST", False);
1521	/* init cursors */
1522	cursor[CurNormal] = drw_cur_create(drw, XC_left_ptr);
1523	cursor[CurResize] = drw_cur_create(drw, XC_sizing);
1524	cursor[CurMove] = drw_cur_create(drw, XC_fleur);
1525	/* init appearance */
1526	thmnorm->border = drw_clr_create(drw, normbordercolor);
1527	thmnorm->bg = drw_clr_create(drw, normbgcolor);
1528	thmnorm->fg = drw_clr_create(drw, normfgcolor);
1529	thmsel->border = drw_clr_create(drw, selbordercolor);
1530	thmsel->bg = drw_clr_create(drw, selbgcolor);
1531	thmsel->fg = drw_clr_create(drw, selfgcolor);
1532	/* init bars */
1533	updatebars();
1534	updatestatus();
1535	/* EWMH support per view */
1536	XChangeProperty(dpy, root, netatom[NetSupported], XA_ATOM, 32,
1537			PropModeReplace, (unsigned char *) netatom, NetLast);
1538	XDeleteProperty(dpy, root, netatom[NetClientList]);
1539	/* select for events */
1540	wa.cursor = cursor[CurNormal]->cursor;
1541	wa.event_mask = SubstructureRedirectMask|SubstructureNotifyMask|ButtonPressMask|PointerMotionMask
1542	                |EnterWindowMask|LeaveWindowMask|StructureNotifyMask|PropertyChangeMask;
1543	XChangeWindowAttributes(dpy, root, CWEventMask|CWCursor, &wa);
1544	XSelectInput(dpy, root, wa.event_mask);
1545	grabkeys();
1546}
1547
1548void
1549showhide(Client *c) {
1550	if(!c)
1551		return;
1552	if(ISVISIBLE(c)) { /* show clients top down */
1553		XMoveWindow(dpy, c->win, c->x, c->y);
1554		if((!c->mon->lt[c->mon->sellt]->arrange || c->isfloating) && !c->isfullscreen)
1555			resize(c, c->x, c->y, c->w, c->h, False);
1556		showhide(c->snext);
1557	}
1558	else { /* hide clients bottom up */
1559		showhide(c->snext);
1560		XMoveWindow(dpy, c->win, WIDTH(c) * -2, c->y);
1561	}
1562}
1563
1564void
1565sigchld(int unused) {
1566	if(signal(SIGCHLD, sigchld) == SIG_ERR)
1567		die("Can't install SIGCHLD handler");
1568	while(0 < waitpid(-1, NULL, WNOHANG));
1569}
1570
1571void
1572spawn(const Arg *arg) {
1573	if(fork() == 0) {
1574		if(dpy)
1575			close(ConnectionNumber(dpy));
1576		setsid();
1577		execvp(((char **)arg->v)[0], (char **)arg->v);
1578		fprintf(stderr, "dwm: execvp %s", ((char **)arg->v)[0]);
1579		perror(" failed");
1580		exit(EXIT_SUCCESS);
1581	}
1582}
1583
1584void
1585tag(const Arg *arg) {
1586	if(selmon->sel && arg->ui & TAGMASK) {
1587		selmon->sel->tags = arg->ui & TAGMASK;
1588		focus(NULL);
1589		arrange(selmon);
1590	}
1591}
1592
1593void
1594tagmon(const Arg *arg) {
1595	if(!selmon->sel || !mons->next)
1596		return;
1597	sendmon(selmon->sel, dirtomon(arg->i));
1598}
1599
1600void
1601tile(Monitor *m) {
1602	unsigned int i, n, h, mw, my, ty;
1603	Client *c;
1604
1605	for(n = 0, c = nexttiled(m->clients); c; c = nexttiled(c->next), n++);
1606	if(n == 0)
1607		return;
1608
1609	if(n > m->nmaster)
1610		mw = m->nmaster ? m->ww * m->mfact : 0;
1611	else
1612		mw = m->ww;
1613	for(i = my = ty = 0, c = nexttiled(m->clients); c; c = nexttiled(c->next), i++)
1614		if(i < m->nmaster) {
1615			h = (m->wh - my) / (MIN(n, m->nmaster) - i);
1616			resize(c, m->wx, m->wy + my, mw - (2*c->bw), h - (2*c->bw), False);
1617			my += HEIGHT(c);
1618		}
1619		else {
1620			h = (m->wh - ty) / (n - i);
1621			resize(c, m->wx + mw, m->wy + ty, m->ww - mw - (2*c->bw), h - (2*c->bw), False);
1622			ty += HEIGHT(c);
1623		}
1624}
1625
1626void
1627togglebar(const Arg *arg) {
1628	selmon->showbar = !selmon->showbar;
1629	updatebarpos(selmon);
1630	XMoveResizeWindow(dpy, selmon->barwin, selmon->wx, selmon->by, selmon->ww, bh);
1631	arrange(selmon);
1632}
1633
1634void
1635togglefloating(const Arg *arg) {
1636	if(!selmon->sel)
1637		return;
1638	if(selmon->sel->isfullscreen) /* no support for fullscreen windows */
1639		return;
1640	selmon->sel->isfloating = !selmon->sel->isfloating || selmon->sel->isfixed;
1641	if(selmon->sel->isfloating)
1642		resize(selmon->sel, selmon->sel->x, selmon->sel->y,
1643		       selmon->sel->w, selmon->sel->h, False);
1644	arrange(selmon);
1645}
1646
1647void
1648toggletag(const Arg *arg) {
1649	unsigned int newtags;
1650
1651	if(!selmon->sel)
1652		return;
1653	newtags = selmon->sel->tags ^ (arg->ui & TAGMASK);
1654	if(newtags) {
1655		selmon->sel->tags = newtags;
1656		focus(NULL);
1657		arrange(selmon);
1658	}
1659}
1660
1661void
1662toggleview(const Arg *arg) {
1663	unsigned int newtagset = selmon->tagset[selmon->seltags] ^ (arg->ui & TAGMASK);
1664
1665	if(newtagset) {
1666		selmon->tagset[selmon->seltags] = newtagset;
1667		focus(NULL);
1668		arrange(selmon);
1669	}
1670}
1671
1672void
1673unfocus(Client *c, Bool setfocus) {
1674	if(!c)
1675		return;
1676	grabbuttons(c, False);
1677	XSetWindowBorder(dpy, c->win, thmnorm->border->rgb);
1678	if(setfocus) {
1679		XSetInputFocus(dpy, root, RevertToPointerRoot, CurrentTime);
1680		XDeleteProperty(dpy, root, netatom[NetActiveWindow]);
1681	}
1682}
1683
1684void
1685unmanage(Client *c, Bool destroyed) {
1686	Monitor *m = c->mon;
1687	XWindowChanges wc;
1688
1689	/* The server grab construct avoids race conditions. */
1690	detach(c);
1691	detachstack(c);
1692	if(!destroyed) {
1693		wc.border_width = c->oldbw;
1694		XGrabServer(dpy);
1695		XSetErrorHandler(xerrordummy);
1696		XConfigureWindow(dpy, c->win, CWBorderWidth, &wc); /* restore border */
1697		XUngrabButton(dpy, AnyButton, AnyModifier, c->win);
1698		setclientstate(c, WithdrawnState);
1699		XSync(dpy, False);
1700		XSetErrorHandler(xerror);
1701		XUngrabServer(dpy);
1702	}
1703	free(c);
1704	focus(NULL);
1705	updateclientlist();
1706	arrange(m);
1707}
1708
1709void
1710unmapnotify(XEvent *e) {
1711	Client *c;
1712	XUnmapEvent *ev = &e->xunmap;
1713
1714	if((c = wintoclient(ev->window))) {
1715		if(ev->send_event)
1716			setclientstate(c, WithdrawnState);
1717		else
1718			unmanage(c, False);
1719	}
1720}
1721
1722void
1723updatebars(void) {
1724	Monitor *m;
1725	XSetWindowAttributes wa = {
1726		.override_redirect = True,
1727		.background_pixmap = ParentRelative,
1728		.event_mask = ButtonPressMask|ExposureMask
1729	};
1730	for(m = mons; m; m = m->next) {
1731		if (m->barwin)
1732			continue;
1733		m->barwin = XCreateWindow(dpy, root, m->wx, m->by, m->ww, bh, 0, DefaultDepth(dpy, screen),
1734		                          CopyFromParent, DefaultVisual(dpy, screen),
1735		                          CWOverrideRedirect|CWBackPixmap|CWEventMask, &wa);
1736		XDefineCursor(dpy, m->barwin, cursor[CurNormal]->cursor);
1737		XMapRaised(dpy, m->barwin);
1738	}
1739}
1740
1741void
1742updatebarpos(Monitor *m) {
1743	m->wy = m->my;
1744	m->wh = m->mh;
1745	if(m->showbar) {
1746		m->wh -= bh;
1747		m->by = m->topbar ? m->wy : m->wy + m->wh;
1748		m->wy = m->topbar ? m->wy + bh : m->wy;
1749	}
1750	else
1751		m->by = -bh;
1752}
1753
1754void
1755updateclientlist() {
1756	Client *c;
1757	Monitor *m;
1758
1759	XDeleteProperty(dpy, root, netatom[NetClientList]);
1760	for(m = mons; m; m = m->next)
1761		for(c = m->clients; c; c = c->next)
1762			XChangeProperty(dpy, root, netatom[NetClientList],
1763			                XA_WINDOW, 32, PropModeAppend,
1764			                (unsigned char *) &(c->win), 1);
1765}
1766
1767Bool
1768updategeom(void) {
1769	Bool dirty = False;
1770
1771#ifdef XINERAMA
1772	if(XineramaIsActive(dpy)) {
1773		int i, j, n, nn;
1774		Client *c;
1775		Monitor *m;
1776		XineramaScreenInfo *info = XineramaQueryScreens(dpy, &nn);
1777		XineramaScreenInfo *unique = NULL;
1778
1779		for(n = 0, m = mons; m; m = m->next, n++);
1780		/* only consider unique geometries as separate screens */
1781		if(!(unique = (XineramaScreenInfo *)malloc(sizeof(XineramaScreenInfo) * nn)))
1782			die("fatal: could not malloc() %u bytes\n", sizeof(XineramaScreenInfo) * nn);
1783		for(i = 0, j = 0; i < nn; i++)
1784			if(isuniquegeom(unique, j, &info[i]))
1785				memcpy(&unique[j++], &info[i], sizeof(XineramaScreenInfo));
1786		XFree(info);
1787		nn = j;
1788		if(n <= nn) {
1789			for(i = 0; i < (nn - n); i++) { /* new monitors available */
1790				for(m = mons; m && m->next; m = m->next);
1791				if(m)
1792					m->next = createmon();
1793				else
1794					mons = createmon();
1795			}
1796			for(i = 0, m = mons; i < nn && m; m = m->next, i++)
1797				if(i >= n
1798				|| (unique[i].x_org != m->mx || unique[i].y_org != m->my
1799				    || unique[i].width != m->mw || unique[i].height != m->mh))
1800				{
1801					dirty = True;
1802					m->num = i;
1803					m->mx = m->wx = unique[i].x_org;
1804					m->my = m->wy = unique[i].y_org;
1805					m->mw = m->ww = unique[i].width;
1806					m->mh = m->wh = unique[i].height;
1807					updatebarpos(m);
1808				}
1809		}
1810		else { /* less monitors available nn < n */
1811			for(i = nn; i < n; i++) {
1812				for(m = mons; m && m->next; m = m->next);
1813				while(m->clients) {
1814					dirty = True;
1815					c = m->clients;
1816					m->clients = c->next;
1817					detachstack(c);
1818					c->mon = mons;
1819					attach(c);
1820					attachstack(c);
1821				}
1822				if(m == selmon)
1823					selmon = mons;
1824				cleanupmon(m);
1825			}
1826		}
1827		free(unique);
1828	}
1829	else
1830#endif /* XINERAMA */
1831	/* default monitor setup */
1832	{
1833		if(!mons)
1834			mons = createmon();
1835		if(mons->mw != sw || mons->mh != sh) {
1836			dirty = True;
1837			mons->mw = mons->ww = sw;
1838			mons->mh = mons->wh = sh;
1839			updatebarpos(mons);
1840		}
1841	}
1842	if(dirty) {
1843		selmon = mons;
1844		selmon = wintomon(root);
1845	}
1846	return dirty;
1847}
1848
1849void
1850updatenumlockmask(void) {
1851	unsigned int i, j;
1852	XModifierKeymap *modmap;
1853
1854	numlockmask = 0;
1855	modmap = XGetModifierMapping(dpy);
1856	for(i = 0; i < 8; i++)
1857		for(j = 0; j < modmap->max_keypermod; j++)
1858			if(modmap->modifiermap[i * modmap->max_keypermod + j]
1859			   == XKeysymToKeycode(dpy, XK_Num_Lock))
1860				numlockmask = (1 << i);
1861	XFreeModifiermap(modmap);
1862}
1863
1864void
1865updatesizehints(Client *c) {
1866	long msize;
1867	XSizeHints size;
1868
1869	if(!XGetWMNormalHints(dpy, c->win, &size, &msize))
1870		/* size is uninitialized, ensure that size.flags aren't used */
1871		size.flags = PSize;
1872	if(size.flags & PBaseSize) {
1873		c->basew = size.base_width;
1874		c->baseh = size.base_height;
1875	}
1876	else if(size.flags & PMinSize) {
1877		c->basew = size.min_width;
1878		c->baseh = size.min_height;
1879	}
1880	else
1881		c->basew = c->baseh = 0;
1882	if(size.flags & PResizeInc) {
1883		c->incw = size.width_inc;
1884		c->inch = size.height_inc;
1885	}
1886	else
1887		c->incw = c->inch = 0;
1888	if(size.flags & PMaxSize) {
1889		c->maxw = size.max_width;
1890		c->maxh = size.max_height;
1891	}
1892	else
1893		c->maxw = c->maxh = 0;
1894	if(size.flags & PMinSize) {
1895		c->minw = size.min_width;
1896		c->minh = size.min_height;
1897	}
1898	else if(size.flags & PBaseSize) {
1899		c->minw = size.base_width;
1900		c->minh = size.base_height;
1901	}
1902	else
1903		c->minw = c->minh = 0;
1904	if(size.flags & PAspect) {
1905		c->mina = (float)size.min_aspect.y / size.min_aspect.x;
1906		c->maxa = (float)size.max_aspect.x / size.max_aspect.y;
1907	}
1908	else
1909		c->maxa = c->mina = 0.0;
1910	c->isfixed = (c->maxw && c->minw && c->maxh && c->minh
1911	             && c->maxw == c->minw && c->maxh == c->minh);
1912}
1913
1914void
1915updatetitle(Client *c) {
1916	if(!gettextprop(c->win, netatom[NetWMName], c->name, sizeof c->name))
1917		gettextprop(c->win, XA_WM_NAME, c->name, sizeof c->name);
1918	if(c->name[0] == '\0') /* hack to mark broken clients */
1919		strcpy(c->name, broken);
1920}
1921
1922void
1923updatestatus(void) {
1924	if(!gettextprop(root, XA_WM_NAME, stext, sizeof(stext)))
1925		strcpy(stext, "dwm-"VERSION);
1926	drawbar(selmon);
1927}
1928
1929void
1930updatewindowtype(Client *c) {
1931	Atom state = getatomprop(c, netatom[NetWMState]);
1932	Atom wtype = getatomprop(c, netatom[NetWMWindowType]);
1933
1934	if(state == netatom[NetWMFullscreen])
1935		setfullscreen(c, True);
1936	if(wtype == netatom[NetWMWindowTypeDialog])
1937		c->isfloating = True;
1938}
1939
1940void
1941updatewmhints(Client *c) {
1942	XWMHints *wmh;
1943
1944	if((wmh = XGetWMHints(dpy, c->win))) {
1945		if(c == selmon->sel && wmh->flags & XUrgencyHint) {
1946			wmh->flags &= ~XUrgencyHint;
1947			XSetWMHints(dpy, c->win, wmh);
1948		}
1949		else
1950			c->isurgent = (wmh->flags & XUrgencyHint) ? True : False;
1951		if(wmh->flags & InputHint)
1952			c->neverfocus = !wmh->input;
1953		else
1954			c->neverfocus = False;
1955		XFree(wmh);
1956	}
1957}
1958
1959void
1960view(const Arg *arg) {
1961	if((arg->ui & TAGMASK) == selmon->tagset[selmon->seltags])
1962		return;
1963	selmon->seltags ^= 1; /* toggle sel tagset */
1964	if(arg->ui & TAGMASK)
1965		selmon->tagset[selmon->seltags] = arg->ui & TAGMASK;
1966	focus(NULL);
1967	arrange(selmon);
1968}
1969
1970Client *
1971wintoclient(Window w) {
1972	Client *c;
1973	Monitor *m;
1974
1975	for(m = mons; m; m = m->next)
1976		for(c = m->clients; c; c = c->next)
1977			if(c->win == w)
1978				return c;
1979	return NULL;
1980}
1981
1982Monitor *
1983wintomon(Window w) {
1984	int x, y;
1985	Client *c;
1986	Monitor *m;
1987
1988	if(w == root && getrootptr(&x, &y))
1989		return recttomon(x, y, 1, 1);
1990	for(m = mons; m; m = m->next)
1991		if(w == m->barwin)
1992			return m;
1993	if((c = wintoclient(w)))
1994		return c->mon;
1995	return selmon;
1996}
1997
1998/* There's no way to check accesses to destroyed windows, thus those cases are
1999 * ignored (especially on UnmapNotify's).  Other types of errors call Xlibs
2000 * default error handler, which may call exit.  */
2001int
2002xerror(Display *dpy, XErrorEvent *ee) {
2003	if(ee->error_code == BadWindow
2004	|| (ee->request_code == X_SetInputFocus && ee->error_code == BadMatch)
2005	|| (ee->request_code == X_PolyText8 && ee->error_code == BadDrawable)
2006	|| (ee->request_code == X_PolyFillRectangle && ee->error_code == BadDrawable)
2007	|| (ee->request_code == X_PolySegment && ee->error_code == BadDrawable)
2008	|| (ee->request_code == X_ConfigureWindow && ee->error_code == BadMatch)
2009	|| (ee->request_code == X_GrabButton && ee->error_code == BadAccess)
2010	|| (ee->request_code == X_GrabKey && ee->error_code == BadAccess)
2011	|| (ee->request_code == X_CopyArea && ee->error_code == BadDrawable))
2012		return 0;
2013	fprintf(stderr, "dwm: fatal error: request code=%d, error code=%d\n",
2014			ee->request_code, ee->error_code);
2015	return xerrorxlib(dpy, ee); /* may call exit */
2016}
2017
2018int
2019xerrordummy(Display *dpy, XErrorEvent *ee) {
2020	return 0;
2021}
2022
2023/* Startup Error handler to check if another window manager
2024 * is already running. */
2025int
2026xerrorstart(Display *dpy, XErrorEvent *ee) {
2027	die("dwm: another window manager is already running\n");
2028	return -1;
2029}
2030
2031void
2032zoom(const Arg *arg) {
2033	Client *c = selmon->sel;
2034
2035	if(!selmon->lt[selmon->sellt]->arrange
2036	|| (selmon->sel && selmon->sel->isfloating))
2037		return;
2038	if(c == nexttiled(selmon->clients))
2039		if(!c || !(c = nexttiled(c->next)))
2040			return;
2041	pop(c);
2042}
2043
2044int
2045main(int argc, char *argv[]) {
2046	if(argc == 2 && !strcmp("-v", argv[1]))
2047		die("dwm-"VERSION", © 2006-2012 dwm engineers, see LICENSE for details\n");
2048	else if(argc != 1)
2049		die("usage: dwm [-v]\n");
2050	if(!setlocale(LC_CTYPE, "") || !XSupportsLocale())
2051		fputs("warning: no locale support\n", stderr);
2052	if(!(dpy = XOpenDisplay(NULL)))
2053		die("dwm: cannot open display\n");
2054	checkotherwm();
2055	setup();
2056	scan();
2057	run();
2058	cleanup();
2059	XCloseDisplay(dpy);
2060	return EXIT_SUCCESS;
2061}