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 * Calls to fetch an X event from the event queue are blocking.  Due reading
  10 * status text from standard input, a select()-driven main loop has been
  11 * implemented which selects for reads on the X connection and STDIN_FILENO to
  12 * handle all data smoothly. The event handlers of dwm are organized in an
  13 * array which is accessed whenever a new event has been fetched. This allows
  14 * event dispatching in O(1) time.
  15 *
  16 * Each child of the root window is called a client, except windows which have
  17 * set the override_redirect flag.  Clients are organized in a global
  18 * doubly-linked client list, the focus history is remembered through a global
  19 * stack list. Each client contains an array of Bools of the same size as the
  20 * global tags array to indicate the tags of a client.
  21 *
  22 * Keys and tagging rules are organized as arrays and defined in config.h.
  23 *
  24 * To understand everything else, start reading main().
  25 */
  26#include <errno.h>
  27#include <locale.h>
  28#include <stdarg.h>
  29#include <stdio.h>
  30#include <stdlib.h>
  31#include <string.h>
  32#include <unistd.h>
  33#include <sys/select.h>
  34#include <sys/types.h>
  35#include <sys/wait.h>
  36#include <X11/cursorfont.h>
  37#include <X11/keysym.h>
  38#include <X11/Xatom.h>
  39#include <X11/Xlib.h>
  40#include <X11/Xproto.h>
  41#include <X11/Xutil.h>
  42
  43/* macros */
  44#define MAX(a, b)	((a) > (b) ? (a) : (b))
  45#define MIN(a, b)	((a) < (b) ? (a) : (b))
  46#define BUTTONMASK	(ButtonPressMask|ButtonReleaseMask)
  47#define CLEANMASK(mask)	(mask & ~(numlockmask|LockMask))
  48#define LENGTH(x)	(sizeof x / sizeof x[0])
  49#define MAXTAGLEN	16
  50#define MOUSEMASK	(BUTTONMASK|PointerMotionMask)
  51
  52/* enums */
  53enum { CurNormal, CurResize, CurMove, CurLast };	/* cursor */
  54enum { ColBorder, ColFG, ColBG, ColLast };		/* color */
  55enum { NetSupported, NetWMName, NetLast };		/* EWMH atoms */
  56enum { WMProtocols, WMDelete, WMName, WMState, WMLast };/* default atoms */
  57
  58/* typedefs */
  59typedef struct Client Client;
  60struct Client {
  61	char name[256];
  62	int x, y, w, h;
  63	int basew, baseh, incw, inch, maxw, maxh, minw, minh;
  64	int minax, maxax, minay, maxay;
  65	long flags;
  66	unsigned int bw, oldbw;
  67	Bool isbanned, isfixed, isfloating, isurgent;
  68	Bool *tags;
  69	Client *next;
  70	Client *prev;
  71	Client *snext;
  72	Window win;
  73};
  74
  75typedef struct {
  76	int x, y, w, h;
  77	unsigned long norm[ColLast];
  78	unsigned long sel[ColLast];
  79	Drawable drawable;
  80	GC gc;
  81	struct {
  82		int ascent;
  83		int descent;
  84		int height;
  85		XFontSet set;
  86		XFontStruct *xfont;
  87	} font;
  88} DC; /* draw context */
  89
  90typedef struct {
  91	unsigned long mod;
  92	KeySym keysym;
  93	void (*func)(const char *arg);
  94	const char *arg;
  95} Key;
  96
  97typedef struct {
  98	const char *symbol;
  99	void (*arrange)(void);
 100	void (*updategeom)(void);
 101} Layout;
 102
 103typedef struct {
 104	const char *class;
 105	const char *instance;
 106	const char *title;
 107	const char *tag;
 108	Bool isfloating;
 109} Rule;
 110
 111/* function declarations */
 112void applyrules(Client *c);
 113void arrange(void);
 114void attach(Client *c);
 115void attachstack(Client *c);
 116void ban(Client *c);
 117void buttonpress(XEvent *e);
 118void checkotherwm(void);
 119void cleanup(void);
 120void configure(Client *c);
 121void configurenotify(XEvent *e);
 122void configurerequest(XEvent *e);
 123void destroynotify(XEvent *e);
 124void detach(Client *c);
 125void detachstack(Client *c);
 126void drawbar(void);
 127void drawsquare(Bool filled, Bool empty, Bool invert, unsigned long col[ColLast]);
 128void drawtext(const char *text, unsigned long col[ColLast], Bool invert);
 129void *emallocz(unsigned int size);
 130void enternotify(XEvent *e);
 131void eprint(const char *errstr, ...);
 132void expose(XEvent *e);
 133void focus(Client *c);
 134void focusin(XEvent *e);
 135void focusnext(const char *arg);
 136void focusprev(const char *arg);
 137Client *getclient(Window w);
 138unsigned long getcolor(const char *colstr);
 139long getstate(Window w);
 140Bool gettextprop(Window w, Atom atom, char *text, unsigned int size);
 141void grabbuttons(Client *c, Bool focused);
 142void grabkeys(void);
 143unsigned int idxoftag(const char *t);
 144void initfont(const char *fontstr);
 145Bool isoccupied(unsigned int t);
 146Bool isprotodel(Client *c);
 147Bool isurgent(unsigned int t);
 148Bool isvisible(Client *c);
 149void keypress(XEvent *e);
 150void killclient(const char *arg);
 151void manage(Window w, XWindowAttributes *wa);
 152void mappingnotify(XEvent *e);
 153void maprequest(XEvent *e);
 154void movemouse(Client *c);
 155Client *nextunfloating(Client *c);
 156void propertynotify(XEvent *e);
 157void quit(const char *arg);
 158void resize(Client *c, int x, int y, int w, int h, Bool sizehints);
 159void resizemouse(Client *c);
 160void restack(void);
 161void run(void);
 162void scan(void);
 163void setclientstate(Client *c, long state);
 164void setup(void);
 165void spawn(const char *arg);
 166void tag(const char *arg);
 167unsigned int textnw(const char *text, unsigned int len);
 168unsigned int textw(const char *text);
 169void togglefloating(const char *arg);
 170void togglelayout(const char *arg);
 171void toggletag(const char *arg);
 172void toggleview(const char *arg);
 173void unban(Client *c);
 174void unmanage(Client *c);
 175void unmapnotify(XEvent *e);
 176void updatebar(void);
 177void updategeom(void);
 178void updatesizehints(Client *c);
 179void updatetitle(Client *c);
 180void updatewmhints(Client *c);
 181void view(const char *arg);
 182void viewprevtag(const char *arg);	/* views previous selected tags */
 183int xerror(Display *dpy, XErrorEvent *ee);
 184int xerrordummy(Display *dpy, XErrorEvent *ee);
 185int xerrorstart(Display *dpy, XErrorEvent *ee);
 186void zoom(const char *arg);
 187
 188/* variables */
 189char stext[256];
 190int screen, sx, sy, sw, sh;
 191int (*xerrorxlib)(Display *, XErrorEvent *);
 192int bx, by, bw, bh, blw, wx, wy, ww, wh;
 193int seltags = 0;
 194unsigned int numlockmask = 0;
 195void (*handler[LASTEvent]) (XEvent *) = {
 196	[ButtonPress] = buttonpress,
 197	[ConfigureRequest] = configurerequest,
 198	[ConfigureNotify] = configurenotify,
 199	[DestroyNotify] = destroynotify,
 200	[EnterNotify] = enternotify,
 201	[Expose] = expose,
 202	[FocusIn] = focusin,
 203	[KeyPress] = keypress,
 204	[MappingNotify] = mappingnotify,
 205	[MapRequest] = maprequest,
 206	[PropertyNotify] = propertynotify,
 207	[UnmapNotify] = unmapnotify
 208};
 209Atom wmatom[WMLast], netatom[NetLast];
 210Bool otherwm, readin;
 211Bool running = True;
 212Bool *tagset[2];
 213Client *clients = NULL;
 214Client *sel = NULL;
 215Client *stack = NULL;
 216Cursor cursor[CurLast];
 217Display *dpy;
 218DC dc = {0};
 219Layout layouts[];
 220Layout *lt = layouts;
 221Window root, barwin;
 222
 223/* configuration, allows nested code to access above variables */
 224#include "config.h"
 225#define TAGSZ (LENGTH(tags) * sizeof(Bool))
 226
 227/* function implementations */
 228
 229void
 230applyrules(Client *c) {
 231	unsigned int i;
 232	Bool matched = False;
 233	Rule *r;
 234	XClassHint ch = { 0 };
 235
 236	/* rule matching */
 237	XGetClassHint(dpy, c->win, &ch);
 238	for(i = 0; i < LENGTH(rules); i++) {
 239		r = &rules[i];
 240		if((!r->title || strstr(c->name, r->title))
 241		&& (!r->class || (ch.res_class && strstr(ch.res_class, r->class)))
 242		&& (!r->instance || (ch.res_name && strstr(ch.res_name, r->instance)))) {
 243			c->isfloating = r->isfloating;
 244			if(r->tag) {
 245				c->tags[idxoftag(r->tag)] = True;
 246				matched = True;
 247			}
 248		}
 249	}
 250	if(ch.res_class)
 251		XFree(ch.res_class);
 252	if(ch.res_name)
 253		XFree(ch.res_name);
 254	if(!matched)
 255		memcpy(c->tags, tagset[seltags], TAGSZ);
 256}
 257
 258void
 259arrange(void) {
 260	Client *c;
 261
 262	for(c = clients; c; c = c->next)
 263		if(isvisible(c)) {
 264			unban(c);
 265			if(!lt->arrange || c->isfloating)
 266				resize(c, c->x, c->y, c->w, c->h, True);
 267		}
 268		else
 269			ban(c);
 270
 271	focus(NULL);
 272	if(lt->arrange)
 273		lt->arrange();
 274	restack();
 275}
 276
 277void
 278attach(Client *c) {
 279	if(clients)
 280		clients->prev = c;
 281	c->next = clients;
 282	clients = c;
 283}
 284
 285void
 286attachstack(Client *c) {
 287	c->snext = stack;
 288	stack = c;
 289}
 290
 291void
 292ban(Client *c) {
 293	if(c->isbanned)
 294		return;
 295	XMoveWindow(dpy, c->win, c->x + 2 * sw, c->y);
 296	c->isbanned = True;
 297}
 298
 299void
 300buttonpress(XEvent *e) {
 301	unsigned int i, x;
 302	Client *c;
 303	XButtonPressedEvent *ev = &e->xbutton;
 304
 305	if(ev->window == barwin) {
 306		x = 0;
 307		for(i = 0; i < LENGTH(tags); i++) {
 308			x += textw(tags[i]);
 309			if(ev->x < x) {
 310				if(ev->button == Button1) {
 311					if(ev->state & MODKEY)
 312						tag(tags[i]);
 313					else
 314						view(tags[i]);
 315				}
 316				else if(ev->button == Button3) {
 317					if(ev->state & MODKEY)
 318						toggletag(tags[i]);
 319					else
 320						toggleview(tags[i]);
 321				}
 322				return;
 323			}
 324		}
 325		if((ev->x < x + blw) && ev->button == Button1) 
 326			togglelayout(NULL);
 327	}
 328	else if((c = getclient(ev->window))) {
 329		focus(c);
 330		if(CLEANMASK(ev->state) != MODKEY)
 331			return;
 332		if(ev->button == Button1) {
 333			restack();
 334			movemouse(c);
 335		}
 336		else if(ev->button == Button2) {
 337			if(lt->arrange && c->isfloating)
 338				togglefloating(NULL);
 339		}
 340		else if(ev->button == Button3 && !c->isfixed) {
 341			restack();
 342			resizemouse(c);
 343		}
 344	}
 345}
 346
 347void
 348checkotherwm(void) {
 349	otherwm = False;
 350	XSetErrorHandler(xerrorstart);
 351
 352	/* this causes an error if some other window manager is running */
 353	XSelectInput(dpy, DefaultRootWindow(dpy), SubstructureRedirectMask);
 354	XSync(dpy, False);
 355	if(otherwm)
 356		eprint("dwm: another window manager is already running\n");
 357	XSync(dpy, False);
 358	XSetErrorHandler(NULL);
 359	xerrorxlib = XSetErrorHandler(xerror);
 360	XSync(dpy, False);
 361}
 362
 363void
 364cleanup(void) {
 365	close(STDIN_FILENO);
 366	while(stack) {
 367		unban(stack);
 368		unmanage(stack);
 369	}
 370	if(dc.font.set)
 371		XFreeFontSet(dpy, dc.font.set);
 372	else
 373		XFreeFont(dpy, dc.font.xfont);
 374	XUngrabKey(dpy, AnyKey, AnyModifier, root);
 375	XFreePixmap(dpy, dc.drawable);
 376	XFreeGC(dpy, dc.gc);
 377	XFreeCursor(dpy, cursor[CurNormal]);
 378	XFreeCursor(dpy, cursor[CurResize]);
 379	XFreeCursor(dpy, cursor[CurMove]);
 380	XDestroyWindow(dpy, barwin);
 381	XSync(dpy, False);
 382	XSetInputFocus(dpy, PointerRoot, RevertToPointerRoot, CurrentTime);
 383}
 384
 385void
 386configure(Client *c) {
 387	XConfigureEvent ce;
 388
 389	ce.type = ConfigureNotify;
 390	ce.display = dpy;
 391	ce.event = c->win;
 392	ce.window = c->win;
 393	ce.x = c->x;
 394	ce.y = c->y;
 395	ce.width = c->w;
 396	ce.height = c->h;
 397	ce.border_width = c->bw;
 398	ce.above = None;
 399	ce.override_redirect = False;
 400	XSendEvent(dpy, c->win, False, StructureNotifyMask, (XEvent *)&ce);
 401}
 402
 403void
 404configurenotify(XEvent *e) {
 405	XConfigureEvent *ev = &e->xconfigure;
 406
 407	if(ev->window == root && (ev->width != sw || ev->height != sh)) {
 408		sw = ev->width;
 409		sh = ev->height;
 410		updategeom();
 411		updatebar();
 412		arrange();
 413	}
 414}
 415
 416void
 417configurerequest(XEvent *e) {
 418	Client *c;
 419	XConfigureRequestEvent *ev = &e->xconfigurerequest;
 420	XWindowChanges wc;
 421
 422	if((c = getclient(ev->window))) {
 423		if(ev->value_mask & CWBorderWidth)
 424			c->bw = ev->border_width;
 425		if(c->isfixed || c->isfloating || !lt->arrange) {
 426			if(ev->value_mask & CWX)
 427				c->x = sx + ev->x;
 428			if(ev->value_mask & CWY)
 429				c->y = sy + ev->y;
 430			if(ev->value_mask & CWWidth)
 431				c->w = ev->width;
 432			if(ev->value_mask & CWHeight)
 433				c->h = ev->height;
 434			if((c->x - sx + c->w) > sw && c->isfloating)
 435				c->x = sx + (sw / 2 - c->w / 2); /* center in x direction */
 436			if((c->y - sy + c->h) > sh && c->isfloating)
 437				c->y = sy + (sh / 2 - c->h / 2); /* center in y direction */
 438			if((ev->value_mask & (CWX|CWY))
 439			&& !(ev->value_mask & (CWWidth|CWHeight)))
 440				configure(c);
 441			if(isvisible(c))
 442				XMoveResizeWindow(dpy, c->win, c->x, c->y, c->w, c->h);
 443		}
 444		else
 445			configure(c);
 446	}
 447	else {
 448		wc.x = ev->x;
 449		wc.y = ev->y;
 450		wc.width = ev->width;
 451		wc.height = ev->height;
 452		wc.border_width = ev->border_width;
 453		wc.sibling = ev->above;
 454		wc.stack_mode = ev->detail;
 455		XConfigureWindow(dpy, ev->window, ev->value_mask, &wc);
 456	}
 457	XSync(dpy, False);
 458}
 459
 460void
 461destroynotify(XEvent *e) {
 462	Client *c;
 463	XDestroyWindowEvent *ev = &e->xdestroywindow;
 464
 465	if((c = getclient(ev->window)))
 466		unmanage(c);
 467}
 468
 469void
 470detach(Client *c) {
 471	if(c->prev)
 472		c->prev->next = c->next;
 473	if(c->next)
 474		c->next->prev = c->prev;
 475	if(c == clients)
 476		clients = c->next;
 477	c->next = c->prev = NULL;
 478}
 479
 480void
 481detachstack(Client *c) {
 482	Client **tc;
 483
 484	for(tc = &stack; *tc && *tc != c; tc = &(*tc)->snext);
 485	*tc = c->snext;
 486}
 487
 488void
 489drawbar(void) {
 490	int i, x;
 491	Client *c;
 492
 493	dc.x = 0;
 494	for(c = stack; c && !isvisible(c); c = c->snext);
 495	for(i = 0; i < LENGTH(tags); i++) {
 496		dc.w = textw(tags[i]);
 497		if(tagset[seltags][i]) {
 498			drawtext(tags[i], dc.sel, isurgent(i));
 499			drawsquare(c && c->tags[i], isoccupied(i), isurgent(i), dc.sel);
 500		}
 501		else {
 502			drawtext(tags[i], dc.norm, isurgent(i));
 503			drawsquare(c && c->tags[i], isoccupied(i), isurgent(i), dc.norm);
 504		}
 505		dc.x += dc.w;
 506	}
 507	if(blw > 0) {
 508		dc.w = blw;
 509		drawtext(lt->symbol, dc.norm, False);
 510		x = dc.x + dc.w;
 511	}
 512	else
 513		x = dc.x;
 514	dc.w = textw(stext);
 515	dc.x = bw - dc.w;
 516	if(dc.x < x) {
 517		dc.x = x;
 518		dc.w = bw - x;
 519	}
 520	drawtext(stext, dc.norm, False);
 521	if((dc.w = dc.x - x) > bh) {
 522		dc.x = x;
 523		if(c) {
 524			drawtext(c->name, dc.sel, False);
 525			drawsquare(False, c->isfloating, False, dc.sel);
 526		}
 527		else
 528			drawtext(NULL, dc.norm, False);
 529	}
 530	XCopyArea(dpy, dc.drawable, barwin, dc.gc, 0, 0, bw, bh, 0, 0);
 531	XSync(dpy, False);
 532}
 533
 534void
 535drawsquare(Bool filled, Bool empty, Bool invert, unsigned long col[ColLast]) {
 536	int x;
 537	XGCValues gcv;
 538	XRectangle r = { dc.x, dc.y, dc.w, dc.h };
 539
 540	gcv.foreground = col[invert ? ColBG : ColFG];
 541	XChangeGC(dpy, dc.gc, GCForeground, &gcv);
 542	x = (dc.font.ascent + dc.font.descent + 2) / 4;
 543	r.x = dc.x + 1;
 544	r.y = dc.y + 1;
 545	if(filled) {
 546		r.width = r.height = x + 1;
 547		XFillRectangles(dpy, dc.drawable, dc.gc, &r, 1);
 548	}
 549	else if(empty) {
 550		r.width = r.height = x;
 551		XDrawRectangles(dpy, dc.drawable, dc.gc, &r, 1);
 552	}
 553}
 554
 555void
 556drawtext(const char *text, unsigned long col[ColLast], Bool invert) {
 557	int x, y, w, h;
 558	unsigned int len, olen;
 559	XRectangle r = { dc.x, dc.y, dc.w, dc.h };
 560	char buf[256];
 561
 562	XSetForeground(dpy, dc.gc, col[invert ? ColFG : ColBG]);
 563	XFillRectangles(dpy, dc.drawable, dc.gc, &r, 1);
 564	if(!text)
 565		return;
 566	olen = strlen(text);
 567	len = MIN(olen, sizeof buf);
 568	memcpy(buf, text, len);
 569	w = 0;
 570	h = dc.font.ascent + dc.font.descent;
 571	y = dc.y + (dc.h / 2) - (h / 2) + dc.font.ascent;
 572	x = dc.x + (h / 2);
 573	/* shorten text if necessary */
 574	for(; len && (w = textnw(buf, len)) > dc.w - h; len--);
 575	if(!len)
 576		return;
 577	if(len < olen) {
 578		if(len > 1)
 579			buf[len - 1] = '.';
 580		if(len > 2)
 581			buf[len - 2] = '.';
 582		if(len > 3)
 583			buf[len - 3] = '.';
 584	}
 585	XSetForeground(dpy, dc.gc, col[invert ? ColBG : ColFG]);
 586	if(dc.font.set)
 587		XmbDrawString(dpy, dc.drawable, dc.font.set, dc.gc, x, y, buf, len);
 588	else
 589		XDrawString(dpy, dc.drawable, dc.gc, x, y, buf, len);
 590}
 591
 592void *
 593emallocz(unsigned int size) {
 594	void *res = calloc(1, size);
 595
 596	if(!res)
 597		eprint("fatal: could not malloc() %u bytes\n", size);
 598	return res;
 599}
 600
 601void
 602enternotify(XEvent *e) {
 603	Client *c;
 604	XCrossingEvent *ev = &e->xcrossing;
 605
 606	if((ev->mode != NotifyNormal || ev->detail == NotifyInferior) && ev->window != root)
 607		return;
 608	if((c = getclient(ev->window)))
 609		focus(c);
 610	else
 611		focus(NULL);
 612}
 613
 614void
 615eprint(const char *errstr, ...) {
 616	va_list ap;
 617
 618	va_start(ap, errstr);
 619	vfprintf(stderr, errstr, ap);
 620	va_end(ap);
 621	exit(EXIT_FAILURE);
 622}
 623
 624void
 625expose(XEvent *e) {
 626	XExposeEvent *ev = &e->xexpose;
 627
 628	if(ev->count == 0 && (ev->window == barwin))
 629		drawbar();
 630}
 631
 632void
 633focus(Client *c) {
 634	if(!c || (c && !isvisible(c)))
 635		for(c = stack; c && !isvisible(c); c = c->snext);
 636	if(sel && sel != c) {
 637		grabbuttons(sel, False);
 638		XSetWindowBorder(dpy, sel->win, dc.norm[ColBorder]);
 639	}
 640	if(c) {
 641		detachstack(c);
 642		attachstack(c);
 643		grabbuttons(c, True);
 644	}
 645	sel = c;
 646	if(c) {
 647		XSetWindowBorder(dpy, c->win, dc.sel[ColBorder]);
 648		XSetInputFocus(dpy, c->win, RevertToPointerRoot, CurrentTime);
 649	}
 650	else
 651		XSetInputFocus(dpy, root, RevertToPointerRoot, CurrentTime);
 652	drawbar();
 653}
 654
 655void
 656focusin(XEvent *e) { /* there are some broken focus acquiring clients */
 657	XFocusChangeEvent *ev = &e->xfocus;
 658
 659	if(sel && ev->window != sel->win)
 660		XSetInputFocus(dpy, sel->win, RevertToPointerRoot, CurrentTime);
 661}
 662
 663void
 664focusnext(const char *arg) {
 665	Client *c;
 666
 667	if(!sel)
 668		return;
 669	for(c = sel->next; c && !isvisible(c); c = c->next);
 670	if(!c)
 671		for(c = clients; c && !isvisible(c); c = c->next);
 672	if(c) {
 673		focus(c);
 674		restack();
 675	}
 676}
 677
 678void
 679focusprev(const char *arg) {
 680	Client *c;
 681
 682	if(!sel)
 683		return;
 684	for(c = sel->prev; c && !isvisible(c); c = c->prev);
 685	if(!c) {
 686		for(c = clients; c && c->next; c = c->next);
 687		for(; c && !isvisible(c); c = c->prev);
 688	}
 689	if(c) {
 690		focus(c);
 691		restack();
 692	}
 693}
 694
 695Client *
 696getclient(Window w) {
 697	Client *c;
 698
 699	for(c = clients; c && c->win != w; c = c->next);
 700	return c;
 701}
 702
 703unsigned long
 704getcolor(const char *colstr) {
 705	Colormap cmap = DefaultColormap(dpy, screen);
 706	XColor color;
 707
 708	if(!XAllocNamedColor(dpy, cmap, colstr, &color, &color))
 709		eprint("error, cannot allocate color '%s'\n", colstr);
 710	return color.pixel;
 711}
 712
 713long
 714getstate(Window w) {
 715	int format, status;
 716	long result = -1;
 717	unsigned char *p = NULL;
 718	unsigned long n, extra;
 719	Atom real;
 720
 721	status = XGetWindowProperty(dpy, w, wmatom[WMState], 0L, 2L, False, wmatom[WMState],
 722			&real, &format, &n, &extra, (unsigned char **)&p);
 723	if(status != Success)
 724		return -1;
 725	if(n != 0)
 726		result = *p;
 727	XFree(p);
 728	return result;
 729}
 730
 731Bool
 732gettextprop(Window w, Atom atom, char *text, unsigned int size) {
 733	char **list = NULL;
 734	int n;
 735	XTextProperty name;
 736
 737	if(!text || size == 0)
 738		return False;
 739	text[0] = '\0';
 740	XGetTextProperty(dpy, w, &name, atom);
 741	if(!name.nitems)
 742		return False;
 743	if(name.encoding == XA_STRING)
 744		strncpy(text, (char *)name.value, size - 1);
 745	else {
 746		if(XmbTextPropertyToTextList(dpy, &name, &list, &n) >= Success
 747		&& n > 0 && *list) {
 748			strncpy(text, *list, size - 1);
 749			XFreeStringList(list);
 750		}
 751	}
 752	text[size - 1] = '\0';
 753	XFree(name.value);
 754	return True;
 755}
 756
 757void
 758grabbuttons(Client *c, Bool focused) {
 759	int i, j;
 760	unsigned int buttons[]   = { Button1, Button2, Button3 };
 761	unsigned int modifiers[] = { MODKEY, MODKEY|LockMask, MODKEY|numlockmask,
 762				MODKEY|numlockmask|LockMask} ;
 763
 764	XUngrabButton(dpy, AnyButton, AnyModifier, c->win);
 765	if(focused)
 766		for(i = 0; i < LENGTH(buttons); i++)
 767			for(j = 0; j < LENGTH(modifiers); j++)
 768				XGrabButton(dpy, buttons[i], modifiers[j], c->win, False,
 769					BUTTONMASK, GrabModeAsync, GrabModeSync, None, None);
 770	else
 771		XGrabButton(dpy, AnyButton, AnyModifier, c->win, False,
 772			BUTTONMASK, GrabModeAsync, GrabModeSync, None, None);
 773}
 774
 775void
 776grabkeys(void) {
 777	unsigned int i, j;
 778	KeyCode code;
 779	XModifierKeymap *modmap;
 780
 781	/* init modifier map */
 782	modmap = XGetModifierMapping(dpy);
 783	for(i = 0; i < 8; i++)
 784		for(j = 0; j < modmap->max_keypermod; j++) {
 785			if(modmap->modifiermap[i * modmap->max_keypermod + j] == XKeysymToKeycode(dpy, XK_Num_Lock))
 786				numlockmask = (1 << i);
 787		}
 788	XFreeModifiermap(modmap);
 789
 790	XUngrabKey(dpy, AnyKey, AnyModifier, root);
 791	for(i = 0; i < LENGTH(keys); i++) {
 792		code = XKeysymToKeycode(dpy, keys[i].keysym);
 793		XGrabKey(dpy, code, keys[i].mod, root, True,
 794				GrabModeAsync, GrabModeAsync);
 795		XGrabKey(dpy, code, keys[i].mod|LockMask, root, True,
 796				GrabModeAsync, GrabModeAsync);
 797		XGrabKey(dpy, code, keys[i].mod|numlockmask, root, True,
 798				GrabModeAsync, GrabModeAsync);
 799		XGrabKey(dpy, code, keys[i].mod|numlockmask|LockMask, root, True,
 800				GrabModeAsync, GrabModeAsync);
 801	}
 802}
 803
 804unsigned int
 805idxoftag(const char *t) {
 806	unsigned int i;
 807
 808	for(i = 0; (i < LENGTH(tags)) && t && strcmp(tags[i], t); i++);
 809	return (i < LENGTH(tags)) ? i : 0;
 810}
 811
 812void
 813initfont(const char *fontstr) {
 814	char *def, **missing;
 815	int i, n;
 816
 817	missing = NULL;
 818	if(dc.font.set)
 819		XFreeFontSet(dpy, dc.font.set);
 820	dc.font.set = XCreateFontSet(dpy, fontstr, &missing, &n, &def);
 821	if(missing) {
 822		while(n--)
 823			fprintf(stderr, "dwm: missing fontset: %s\n", missing[n]);
 824		XFreeStringList(missing);
 825	}
 826	if(dc.font.set) {
 827		XFontSetExtents *font_extents;
 828		XFontStruct **xfonts;
 829		char **font_names;
 830		dc.font.ascent = dc.font.descent = 0;
 831		font_extents = XExtentsOfFontSet(dc.font.set);
 832		n = XFontsOfFontSet(dc.font.set, &xfonts, &font_names);
 833		for(i = 0, dc.font.ascent = 0, dc.font.descent = 0; i < n; i++) {
 834			dc.font.ascent = MAX(dc.font.ascent, (*xfonts)->ascent);
 835			dc.font.descent = MAX(dc.font.descent,(*xfonts)->descent);
 836			xfonts++;
 837		}
 838	}
 839	else {
 840		if(dc.font.xfont)
 841			XFreeFont(dpy, dc.font.xfont);
 842		dc.font.xfont = NULL;
 843		if(!(dc.font.xfont = XLoadQueryFont(dpy, fontstr))
 844		&& !(dc.font.xfont = XLoadQueryFont(dpy, "fixed")))
 845			eprint("error, cannot load font: '%s'\n", fontstr);
 846		dc.font.ascent = dc.font.xfont->ascent;
 847		dc.font.descent = dc.font.xfont->descent;
 848	}
 849	dc.font.height = dc.font.ascent + dc.font.descent;
 850}
 851
 852Bool
 853isoccupied(unsigned int t) {
 854	Client *c;
 855
 856	for(c = clients; c; c = c->next)
 857		if(c->tags[t])
 858			return True;
 859	return False;
 860}
 861
 862Bool
 863isprotodel(Client *c) {
 864	int i, n;
 865	Atom *protocols;
 866	Bool ret = False;
 867
 868	if(XGetWMProtocols(dpy, c->win, &protocols, &n)) {
 869		for(i = 0; !ret && i < n; i++)
 870			if(protocols[i] == wmatom[WMDelete])
 871				ret = True;
 872		XFree(protocols);
 873	}
 874	return ret;
 875}
 876
 877Bool
 878isurgent(unsigned int t) {
 879	Client *c;
 880
 881	for(c = clients; c; c = c->next)
 882		if(c->isurgent && c->tags[t])
 883			return True;
 884	return False;
 885}
 886
 887Bool
 888isvisible(Client *c) {
 889	unsigned int i;
 890
 891	for(i = 0; i < LENGTH(tags); i++)
 892		if(c->tags[i] && tagset[seltags][i])
 893			return True;
 894	return False;
 895}
 896
 897void
 898keypress(XEvent *e) {
 899	unsigned int i;
 900	KeySym keysym;
 901	XKeyEvent *ev;
 902
 903	ev = &e->xkey;
 904	keysym = XKeycodeToKeysym(dpy, (KeyCode)ev->keycode, 0);
 905	for(i = 0; i < LENGTH(keys); i++)
 906		if(keysym == keys[i].keysym
 907		&& CLEANMASK(keys[i].mod) == CLEANMASK(ev->state))
 908		{
 909			if(keys[i].func)
 910				keys[i].func(keys[i].arg);
 911		}
 912}
 913
 914void
 915killclient(const char *arg) {
 916	XEvent ev;
 917
 918	if(!sel)
 919		return;
 920	if(isprotodel(sel)) {
 921		ev.type = ClientMessage;
 922		ev.xclient.window = sel->win;
 923		ev.xclient.message_type = wmatom[WMProtocols];
 924		ev.xclient.format = 32;
 925		ev.xclient.data.l[0] = wmatom[WMDelete];
 926		ev.xclient.data.l[1] = CurrentTime;
 927		XSendEvent(dpy, sel->win, False, NoEventMask, &ev);
 928	}
 929	else
 930		XKillClient(dpy, sel->win);
 931}
 932
 933void
 934manage(Window w, XWindowAttributes *wa) {
 935	Client *c, *t = NULL;
 936	Status rettrans;
 937	Window trans;
 938	XWindowChanges wc;
 939
 940	c = emallocz(sizeof(Client));
 941	c->tags = emallocz(TAGSZ);
 942	c->win = w;
 943
 944	/* geometry */
 945	c->x = wa->x;
 946	c->y = wa->y;
 947	c->w = wa->width;
 948	c->h = wa->height;
 949	c->oldbw = wa->border_width;
 950	if(c->w == sw && c->h == sh) {
 951		c->x = sx;
 952		c->y = sy;
 953		c->bw = wa->border_width;
 954	}
 955	else {
 956		if(c->x + c->w + 2 * c->bw > wx + ww)
 957			c->x = wx + ww - c->w - 2 * c->bw;
 958		if(c->y + c->h + 2 * c->bw > wy + wh)
 959			c->y = wy + wh - c->h - 2 * c->bw;
 960		c->x = MAX(c->x, wx);
 961		c->y = MAX(c->y, wy);
 962		c->bw = BORDERPX;
 963	}
 964
 965	wc.border_width = c->bw;
 966	XConfigureWindow(dpy, w, CWBorderWidth, &wc);
 967	XSetWindowBorder(dpy, w, dc.norm[ColBorder]);
 968	configure(c); /* propagates border_width, if size doesn't change */
 969	updatesizehints(c);
 970	XSelectInput(dpy, w, EnterWindowMask|FocusChangeMask|PropertyChangeMask|StructureNotifyMask);
 971	grabbuttons(c, False);
 972	updatetitle(c);
 973	if((rettrans = XGetTransientForHint(dpy, w, &trans) == Success))
 974		for(t = clients; t && t->win != trans; t = t->next);
 975	if(t)
 976		memcpy(c->tags, t->tags, TAGSZ);
 977	else
 978		applyrules(c);
 979	if(!c->isfloating)
 980		c->isfloating = (rettrans == Success) || c->isfixed;
 981	attach(c);
 982	attachstack(c);
 983	XMoveResizeWindow(dpy, c->win, c->x, c->y, c->w, c->h); /* some windows require this */
 984	ban(c);
 985	XMapWindow(dpy, c->win);
 986	setclientstate(c, NormalState);
 987	arrange();
 988}
 989
 990void
 991mappingnotify(XEvent *e) {
 992	XMappingEvent *ev = &e->xmapping;
 993
 994	XRefreshKeyboardMapping(ev);
 995	if(ev->request == MappingKeyboard)
 996		grabkeys();
 997}
 998
 999void
1000maprequest(XEvent *e) {
1001	static XWindowAttributes wa;
1002	XMapRequestEvent *ev = &e->xmaprequest;
1003
1004	if(!XGetWindowAttributes(dpy, ev->window, &wa))
1005		return;
1006	if(wa.override_redirect)
1007		return;
1008	if(!getclient(ev->window))
1009		manage(ev->window, &wa);
1010}
1011
1012void
1013movemouse(Client *c) {
1014	int x1, y1, ocx, ocy, di, nx, ny;
1015	unsigned int dui;
1016	Window dummy;
1017	XEvent ev;
1018
1019	ocx = nx = c->x;
1020	ocy = ny = c->y;
1021	if(XGrabPointer(dpy, root, False, MOUSEMASK, GrabModeAsync, GrabModeAsync,
1022	None, cursor[CurMove], CurrentTime) != GrabSuccess)
1023		return;
1024	XQueryPointer(dpy, root, &dummy, &dummy, &x1, &y1, &di, &di, &dui);
1025	for(;;) {
1026		XMaskEvent(dpy, MOUSEMASK|ExposureMask|SubstructureRedirectMask, &ev);
1027		switch (ev.type) {
1028		case ButtonRelease:
1029			XUngrabPointer(dpy, CurrentTime);
1030			return;
1031		case ConfigureRequest:
1032		case Expose:
1033		case MapRequest:
1034			handler[ev.type](&ev);
1035			break;
1036		case MotionNotify:
1037			XSync(dpy, False);
1038			nx = ocx + (ev.xmotion.x - x1);
1039			ny = ocy + (ev.xmotion.y - y1);
1040			if(abs(wx - nx) < SNAP)
1041				nx = wx;
1042			else if(abs((wx + ww) - (nx + c->w + 2 * c->bw)) < SNAP)
1043				nx = wx + ww - c->w - 2 * c->bw;
1044			if(abs(wy - ny) < SNAP)
1045				ny = wy;
1046			else if(abs((wy + wh) - (ny + c->h + 2 * c->bw)) < SNAP)
1047				ny = wy + wh - c->h - 2 * c->bw;
1048			if(!c->isfloating && lt->arrange && (abs(nx - c->x) > SNAP || abs(ny - c->y) > SNAP))
1049				togglefloating(NULL);
1050			if(!lt->arrange || c->isfloating)
1051				resize(c, nx, ny, c->w, c->h, False);
1052			break;
1053		}
1054	}
1055}
1056
1057Client *
1058nextunfloating(Client *c) {
1059	for(; c && (c->isfloating || !isvisible(c)); c = c->next);
1060	return c;
1061}
1062
1063void
1064propertynotify(XEvent *e) {
1065	Client *c;
1066	Window trans;
1067	XPropertyEvent *ev = &e->xproperty;
1068
1069	if(ev->state == PropertyDelete)
1070		return; /* ignore */
1071	if((c = getclient(ev->window))) {
1072		switch (ev->atom) {
1073		default: break;
1074		case XA_WM_TRANSIENT_FOR:
1075			XGetTransientForHint(dpy, c->win, &trans);
1076			if(!c->isfloating && (c->isfloating = (getclient(trans) != NULL)))
1077				arrange();
1078			break;
1079		case XA_WM_NORMAL_HINTS:
1080			updatesizehints(c);
1081			break;
1082		case XA_WM_HINTS:
1083			updatewmhints(c);
1084			drawbar();
1085			break;
1086		}
1087		if(ev->atom == XA_WM_NAME || ev->atom == netatom[NetWMName]) {
1088			updatetitle(c);
1089			if(c == sel)
1090				drawbar();
1091		}
1092	}
1093}
1094
1095void
1096quit(const char *arg) {
1097	readin = running = False;
1098}
1099
1100void
1101resize(Client *c, int x, int y, int w, int h, Bool sizehints) {
1102	XWindowChanges wc;
1103
1104	if(sizehints) {
1105		/* set minimum possible */
1106		w = MAX(1, w);
1107		h = MAX(1, h);
1108
1109		/* temporarily remove base dimensions */
1110		w -= c->basew;
1111		h -= c->baseh;
1112
1113		/* adjust for aspect limits */
1114		if(c->minax != c->maxax && c->minay != c->maxay 
1115		&& c->minax > 0 && c->maxax > 0 && c->minay > 0 && c->maxay > 0) {
1116			if(w * c->maxay > h * c->maxax)
1117				w = h * c->maxax / c->maxay;
1118			else if(w * c->minay < h * c->minax)
1119				h = w * c->minay / c->minax;
1120		}
1121
1122		/* adjust for increment value */
1123		if(c->incw)
1124			w -= w % c->incw;
1125		if(c->inch)
1126			h -= h % c->inch;
1127
1128		/* restore base dimensions */
1129		w += c->basew;
1130		h += c->baseh;
1131
1132		w = MAX(w, c->minw);
1133		h = MAX(h, c->minh);
1134		
1135		if (c->maxw)
1136			w = MIN(w, c->maxw);
1137
1138		if (c->maxh)
1139			h = MIN(h, c->maxh);
1140	}
1141	if(w <= 0 || h <= 0)
1142		return;
1143	if(x > sx + sw)
1144		x = sw - w - 2 * c->bw;
1145	if(y > sy + sh)
1146		y = sh - h - 2 * c->bw;
1147	if(x + w + 2 * c->bw < sx)
1148		x = sx;
1149	if(y + h + 2 * c->bw < sy)
1150		y = sy;
1151	if(c->x != x || c->y != y || c->w != w || c->h != h) {
1152		c->x = wc.x = x;
1153		c->y = wc.y = y;
1154		c->w = wc.width = w;
1155		c->h = wc.height = h;
1156		wc.border_width = c->bw;
1157		XConfigureWindow(dpy, c->win,
1158				CWX|CWY|CWWidth|CWHeight|CWBorderWidth, &wc);
1159		configure(c);
1160		XSync(dpy, False);
1161	}
1162}
1163
1164void
1165resizemouse(Client *c) {
1166	int ocx, ocy;
1167	int nw, nh;
1168	XEvent ev;
1169
1170	ocx = c->x;
1171	ocy = c->y;
1172	if(XGrabPointer(dpy, root, False, MOUSEMASK, GrabModeAsync, GrabModeAsync,
1173	None, cursor[CurResize], CurrentTime) != GrabSuccess)
1174		return;
1175	XWarpPointer(dpy, None, c->win, 0, 0, 0, 0, c->w + c->bw - 1, c->h + c->bw - 1);
1176	for(;;) {
1177		XMaskEvent(dpy, MOUSEMASK|ExposureMask|SubstructureRedirectMask , &ev);
1178		switch(ev.type) {
1179		case ButtonRelease:
1180			XWarpPointer(dpy, None, c->win, 0, 0, 0, 0,
1181					c->w + c->bw - 1, c->h + c->bw - 1);
1182			XUngrabPointer(dpy, CurrentTime);
1183			while(XCheckMaskEvent(dpy, EnterWindowMask, &ev));
1184			return;
1185		case ConfigureRequest:
1186		case Expose:
1187		case MapRequest:
1188			handler[ev.type](&ev);
1189			break;
1190		case MotionNotify:
1191			XSync(dpy, False);
1192			nw = MAX(ev.xmotion.x - ocx - 2 * c->bw + 1, 1);
1193			nh = MAX(ev.xmotion.y - ocy - 2 * c->bw + 1, 1);
1194			if(!c->isfloating && lt->arrange && (abs(nw - c->w) > SNAP || abs(nh - c->h) > SNAP)) {
1195				togglefloating(NULL);
1196			}
1197			if(!lt->arrange || c->isfloating)
1198				resize(c, c->x, c->y, nw, nh, True);
1199			break;
1200		}
1201	}
1202}
1203
1204void
1205restack(void) {
1206	Client *c;
1207	XEvent ev;
1208	XWindowChanges wc;
1209
1210	drawbar();
1211	if(!sel)
1212		return;
1213	if(sel->isfloating || !lt->arrange)
1214		XRaiseWindow(dpy, sel->win);
1215	if(lt->arrange) {
1216		wc.stack_mode = Below;
1217		wc.sibling = barwin;
1218		for(c = stack; c; c = c->snext)
1219			if(!c->isfloating && isvisible(c)) {
1220				XConfigureWindow(dpy, c->win, CWSibling|CWStackMode, &wc);
1221				wc.sibling = c->win;
1222			}
1223	}
1224	XSync(dpy, False);
1225	while(XCheckMaskEvent(dpy, EnterWindowMask, &ev));
1226}
1227
1228void
1229run(void) {
1230	char *p;
1231	char sbuf[sizeof stext];
1232	fd_set rd;
1233	int r, xfd;
1234	unsigned int len, offset;
1235	XEvent ev;
1236
1237	/* main event loop, also reads status text from stdin */
1238	XSync(dpy, False);
1239	xfd = ConnectionNumber(dpy);
1240	readin = True;
1241	offset = 0;
1242	len = sizeof stext - 1;
1243	sbuf[len] = stext[len] = '\0'; /* 0-terminator is never touched */
1244	while(running) {
1245		FD_ZERO(&rd);
1246		if(readin)
1247			FD_SET(STDIN_FILENO, &rd);
1248		FD_SET(xfd, &rd);
1249		if(select(xfd + 1, &rd, NULL, NULL, NULL) == -1) {
1250			if(errno == EINTR)
1251				continue;
1252			eprint("select failed\n");
1253		}
1254		if(FD_ISSET(STDIN_FILENO, &rd)) {
1255			switch((r = read(STDIN_FILENO, sbuf + offset, len - offset))) {
1256			case -1:
1257				strncpy(stext, strerror(errno), len);
1258				readin = False;
1259				break;
1260			case 0:
1261				strncpy(stext, "EOF", 4);
1262				readin = False;
1263				break;
1264			default:
1265				for(p = sbuf + offset; r > 0; p++, r--, offset++)
1266					if(*p == '\n' || *p == '\0') {
1267						*p = '\0';
1268						strncpy(stext, sbuf, len);
1269						p += r - 1; /* p is sbuf + offset + r - 1 */
1270						for(r = 0; *(p - r) && *(p - r) != '\n'; r++);
1271						offset = r;
1272						if(r)
1273							memmove(sbuf, p - r + 1, r);
1274						break;
1275					}
1276				break;
1277			}
1278			drawbar();
1279		}
1280		while(XPending(dpy)) {
1281			XNextEvent(dpy, &ev);
1282			if(handler[ev.type])
1283				(handler[ev.type])(&ev); /* call handler */
1284		}
1285	}
1286}
1287
1288void
1289scan(void) {
1290	unsigned int i, num;
1291	Window *wins, d1, d2;
1292	XWindowAttributes wa;
1293
1294	wins = NULL;
1295	if(XQueryTree(dpy, root, &d1, &d2, &wins, &num)) {
1296		for(i = 0; i < num; i++) {
1297			if(!XGetWindowAttributes(dpy, wins[i], &wa)
1298			|| wa.override_redirect || XGetTransientForHint(dpy, wins[i], &d1))
1299				continue;
1300			if(wa.map_state == IsViewable || getstate(wins[i]) == IconicState)
1301				manage(wins[i], &wa);
1302		}
1303		for(i = 0; i < num; i++) { /* now the transients */
1304			if(!XGetWindowAttributes(dpy, wins[i], &wa))
1305				continue;
1306			if(XGetTransientForHint(dpy, wins[i], &d1)
1307			&& (wa.map_state == IsViewable || getstate(wins[i]) == IconicState))
1308				manage(wins[i], &wa);
1309		}
1310	}
1311	if(wins)
1312		XFree(wins);
1313}
1314
1315void
1316setclientstate(Client *c, long state) {
1317	long data[] = {state, None};
1318
1319	XChangeProperty(dpy, c->win, wmatom[WMState], wmatom[WMState], 32,
1320			PropModeReplace, (unsigned char *)data, 2);
1321}
1322
1323void
1324setup(void) {
1325	unsigned int i, w;
1326	XSetWindowAttributes wa;
1327
1328	/* init screen */
1329	screen = DefaultScreen(dpy);
1330	root = RootWindow(dpy, screen);
1331	initfont(FONT);
1332	sx = 0;
1333	sy = 0;
1334	sw = DisplayWidth(dpy, screen);
1335	sh = DisplayHeight(dpy, screen);
1336	bh = dc.font.height + 2;
1337	updategeom();
1338
1339	/* init atoms */
1340	wmatom[WMProtocols] = XInternAtom(dpy, "WM_PROTOCOLS", False);
1341	wmatom[WMDelete] = XInternAtom(dpy, "WM_DELETE_WINDOW", False);
1342	wmatom[WMName] = XInternAtom(dpy, "WM_NAME", False);
1343	wmatom[WMState] = XInternAtom(dpy, "WM_STATE", False);
1344	netatom[NetSupported] = XInternAtom(dpy, "_NET_SUPPORTED", False);
1345	netatom[NetWMName] = XInternAtom(dpy, "_NET_WM_NAME", False);
1346
1347	/* init cursors */
1348	wa.cursor = cursor[CurNormal] = XCreateFontCursor(dpy, XC_left_ptr);
1349	cursor[CurResize] = XCreateFontCursor(dpy, XC_sizing);
1350	cursor[CurMove] = XCreateFontCursor(dpy, XC_fleur);
1351
1352	/* init appearance */
1353	dc.norm[ColBorder] = getcolor(NORMBORDERCOLOR);
1354	dc.norm[ColBG] = getcolor(NORMBGCOLOR);
1355	dc.norm[ColFG] = getcolor(NORMFGCOLOR);
1356	dc.sel[ColBorder] = getcolor(SELBORDERCOLOR);
1357	dc.sel[ColBG] = getcolor(SELBGCOLOR);
1358	dc.sel[ColFG] = getcolor(SELFGCOLOR);
1359	initfont(FONT);
1360	dc.h = bh;
1361	dc.drawable = XCreatePixmap(dpy, root, DisplayWidth(dpy, screen), bh, DefaultDepth(dpy, screen));
1362	dc.gc = XCreateGC(dpy, root, 0, 0);
1363	XSetLineAttributes(dpy, dc.gc, 1, LineSolid, CapButt, JoinMiter);
1364	if(!dc.font.set)
1365		XSetFont(dpy, dc.gc, dc.font.xfont->fid);
1366
1367	/* init tags */
1368	tagset[0] = emallocz(TAGSZ);
1369	tagset[1] = emallocz(TAGSZ);
1370	tagset[0][0] = tagset[1][0] = True;
1371
1372	/* init bar */
1373	for(blw = i = 0; LENGTH(layouts) > 1 && i < LENGTH(layouts); i++) {
1374		w = textw(layouts[i].symbol);
1375		blw = MAX(blw, w);
1376	}
1377
1378	wa.override_redirect = 1;
1379	wa.background_pixmap = ParentRelative;
1380	wa.event_mask = ButtonPressMask|ExposureMask;
1381
1382	barwin = XCreateWindow(dpy, root, bx, by, bw, bh, 0, DefaultDepth(dpy, screen),
1383			CopyFromParent, DefaultVisual(dpy, screen),
1384			CWOverrideRedirect|CWBackPixmap|CWEventMask, &wa);
1385	XDefineCursor(dpy, barwin, cursor[CurNormal]);
1386	XMapRaised(dpy, barwin);
1387	strcpy(stext, "dwm-"VERSION);
1388	drawbar();
1389
1390	/* EWMH support per view */
1391	XChangeProperty(dpy, root, netatom[NetSupported], XA_ATOM, 32,
1392			PropModeReplace, (unsigned char *) netatom, NetLast);
1393
1394	/* select for events */
1395	wa.event_mask = SubstructureRedirectMask|SubstructureNotifyMask
1396			|EnterWindowMask|LeaveWindowMask|StructureNotifyMask;
1397	XChangeWindowAttributes(dpy, root, CWEventMask|CWCursor, &wa);
1398	XSelectInput(dpy, root, wa.event_mask);
1399
1400
1401	/* grab keys */
1402	grabkeys();
1403}
1404
1405void
1406spawn(const char *arg) {
1407	static char *shell = NULL;
1408
1409	if(!shell && !(shell = getenv("SHELL")))
1410		shell = "/bin/sh";
1411	if(!arg)
1412		return;
1413	/* The double-fork construct avoids zombie processes and keeps the code
1414	 * clean from stupid signal handlers. */
1415	if(fork() == 0) {
1416		if(fork() == 0) {
1417			if(dpy)
1418				close(ConnectionNumber(dpy));
1419			setsid();
1420			execl(shell, shell, "-c", arg, (char *)NULL);
1421			fprintf(stderr, "dwm: execl '%s -c %s'", shell, arg);
1422			perror(" failed");
1423		}
1424		exit(0);
1425	}
1426	wait(0);
1427}
1428
1429void
1430tag(const char *arg) {
1431	unsigned int i;
1432
1433	if(!sel)
1434		return;
1435	for(i = 0; i < LENGTH(tags); i++)
1436		sel->tags[i] = (arg == NULL);
1437	sel->tags[idxoftag(arg)] = True;
1438	arrange();
1439}
1440
1441unsigned int
1442textnw(const char *text, unsigned int len) {
1443	XRectangle r;
1444
1445	if(dc.font.set) {
1446		XmbTextExtents(dc.font.set, text, len, NULL, &r);
1447		return r.width;
1448	}
1449	return XTextWidth(dc.font.xfont, text, len);
1450}
1451
1452unsigned int
1453textw(const char *text) {
1454	return textnw(text, strlen(text)) + dc.font.height;
1455}
1456
1457void
1458togglefloating(const char *arg) {
1459	if(!sel)
1460		return;
1461	sel->isfloating = !sel->isfloating;
1462	if(sel->isfloating)
1463		resize(sel, sel->x, sel->y, sel->w, sel->h, True);
1464	arrange();
1465}
1466
1467void
1468togglelayout(const char *arg) {
1469	unsigned int i;
1470
1471	if(!arg) {
1472		if(++lt == &layouts[LENGTH(layouts)])
1473			lt = &layouts[0];
1474	}
1475	else {
1476		for(i = 0; i < LENGTH(layouts); i++)
1477			if(!strcmp(arg, layouts[i].symbol))
1478				break;
1479		if(i == LENGTH(layouts))
1480			return;
1481		lt = &layouts[i];
1482	}
1483	if(sel)
1484		arrange();
1485	else
1486		drawbar();
1487}
1488
1489void
1490toggletag(const char *arg) {
1491	unsigned int i, j;
1492
1493	if(!sel)
1494		return;
1495	i = idxoftag(arg);
1496	sel->tags[i] = !sel->tags[i];
1497	for(j = 0; j < LENGTH(tags) && !sel->tags[j]; j++);
1498	if(j == LENGTH(tags))
1499		sel->tags[i] = True; /* at least one tag must be enabled */
1500	arrange();
1501}
1502
1503void
1504toggleview(const char *arg) {
1505	unsigned int i, j;
1506
1507	i = idxoftag(arg);
1508	tagset[seltags][i] = !tagset[seltags][i];
1509	for(j = 0; j < LENGTH(tags) && !tagset[seltags][j]; j++);
1510	if(j == LENGTH(tags))
1511		tagset[seltags][i] = True; /* at least one tag must be viewed */
1512	arrange();
1513}
1514
1515void
1516unban(Client *c) {
1517	if(!c->isbanned)
1518		return;
1519	XMoveWindow(dpy, c->win, c->x, c->y);
1520	c->isbanned = False;
1521}
1522
1523void
1524unmanage(Client *c) {
1525	XWindowChanges wc;
1526
1527	wc.border_width = c->oldbw;
1528	/* The server grab construct avoids race conditions. */
1529	XGrabServer(dpy);
1530	XSetErrorHandler(xerrordummy);
1531	XConfigureWindow(dpy, c->win, CWBorderWidth, &wc); /* restore border */
1532	detach(c);
1533	detachstack(c);
1534	if(sel == c)
1535		focus(NULL);
1536	XUngrabButton(dpy, AnyButton, AnyModifier, c->win);
1537	setclientstate(c, WithdrawnState);
1538	free(c->tags);
1539	free(c);
1540	XSync(dpy, False);
1541	XSetErrorHandler(xerror);
1542	XUngrabServer(dpy);
1543	arrange();
1544}
1545
1546void
1547unmapnotify(XEvent *e) {
1548	Client *c;
1549	XUnmapEvent *ev = &e->xunmap;
1550
1551	if((c = getclient(ev->window)))
1552		unmanage(c);
1553}
1554
1555void
1556updatebar(void) {
1557	if(dc.drawable != 0)
1558		XFreePixmap(dpy, dc.drawable);
1559	dc.drawable = XCreatePixmap(dpy, root, bw, bh, DefaultDepth(dpy, screen));
1560	XMoveResizeWindow(dpy, barwin, bx, by, bw, bh);
1561}
1562
1563void
1564updategeom(void) {
1565	unsigned int i;
1566
1567	/* bar geometry */
1568	bx = 0;
1569	by = 0;
1570	bw = sw;
1571
1572	/* window area geometry */
1573	wx = sx;
1574	wy = sy + bh;
1575	ww = sw;
1576	wh = sh - bh;
1577
1578	/* update layout geometries */
1579	for(i = 0; i < LENGTH(layouts); i++)
1580		if(layouts[i].updategeom)
1581			layouts[i].updategeom();
1582}
1583
1584void
1585updatesizehints(Client *c) {
1586	long msize;
1587	XSizeHints size;
1588
1589	if(!XGetWMNormalHints(dpy, c->win, &size, &msize) || !size.flags)
1590		size.flags = PSize;
1591	c->flags = size.flags;
1592	if(c->flags & PBaseSize) {
1593		c->basew = size.base_width;
1594		c->baseh = size.base_height;
1595	}
1596	else if(c->flags & PMinSize) {
1597		c->basew = size.min_width;
1598		c->baseh = size.min_height;
1599	}
1600	else
1601		c->basew = c->baseh = 0;
1602	if(c->flags & PResizeInc) {
1603		c->incw = size.width_inc;
1604		c->inch = size.height_inc;
1605	}
1606	else
1607		c->incw = c->inch = 0;
1608	if(c->flags & PMaxSize) {
1609		c->maxw = size.max_width;
1610		c->maxh = size.max_height;
1611	}
1612	else
1613		c->maxw = c->maxh = 0;
1614	if(c->flags & PMinSize) {
1615		c->minw = size.min_width;
1616		c->minh = size.min_height;
1617	}
1618	else if(c->flags & PBaseSize) {
1619		c->minw = size.base_width;
1620		c->minh = size.base_height;
1621	}
1622	else
1623		c->minw = c->minh = 0;
1624	if(c->flags & PAspect) {
1625		c->minax = size.min_aspect.x;
1626		c->maxax = size.max_aspect.x;
1627		c->minay = size.min_aspect.y;
1628		c->maxay = size.max_aspect.y;
1629	}
1630	else
1631		c->minax = c->maxax = c->minay = c->maxay = 0;
1632	c->isfixed = (c->maxw && c->minw && c->maxh && c->minh
1633			&& c->maxw == c->minw && c->maxh == c->minh);
1634}
1635
1636void
1637updatetitle(Client *c) {
1638	if(!gettextprop(c->win, netatom[NetWMName], c->name, sizeof c->name))
1639		gettextprop(c->win, wmatom[WMName], c->name, sizeof c->name);
1640}
1641
1642void
1643updatewmhints(Client *c) {
1644	XWMHints *wmh;
1645
1646	if((wmh = XGetWMHints(dpy, c->win))) {
1647		if(c == sel)
1648			sel->isurgent = False;
1649		else
1650			c->isurgent = (wmh->flags & XUrgencyHint) ? True : False;
1651		XFree(wmh);
1652	}
1653}
1654
1655void
1656view(const char *arg) {
1657	seltags ^= 1; /* toggle sel tagset */
1658	memset(tagset[seltags], (NULL == arg), TAGSZ);
1659	tagset[seltags][idxoftag(arg)] = True;
1660	arrange();
1661}
1662
1663void
1664viewprevtag(const char *arg) {
1665	seltags ^= 1; /* toggle sel tagset */
1666	arrange();
1667}
1668
1669/* There's no way to check accesses to destroyed windows, thus those cases are
1670 * ignored (especially on UnmapNotify's).  Other types of errors call Xlibs
1671 * default error handler, which may call exit.  */
1672int
1673xerror(Display *dpy, XErrorEvent *ee) {
1674	if(ee->error_code == BadWindow
1675	|| (ee->request_code == X_SetInputFocus && ee->error_code == BadMatch)
1676	|| (ee->request_code == X_PolyText8 && ee->error_code == BadDrawable)
1677	|| (ee->request_code == X_PolyFillRectangle && ee->error_code == BadDrawable)
1678	|| (ee->request_code == X_PolySegment && ee->error_code == BadDrawable)
1679	|| (ee->request_code == X_ConfigureWindow && ee->error_code == BadMatch)
1680	|| (ee->request_code == X_GrabButton && ee->error_code == BadAccess)
1681	|| (ee->request_code == X_GrabKey && ee->error_code == BadAccess)
1682	|| (ee->request_code == X_CopyArea && ee->error_code == BadDrawable))
1683		return 0;
1684	fprintf(stderr, "dwm: fatal error: request code=%d, error code=%d\n",
1685			ee->request_code, ee->error_code);
1686	return xerrorxlib(dpy, ee); /* may call exit */
1687}
1688
1689int
1690xerrordummy(Display *dpy, XErrorEvent *ee) {
1691	return 0;
1692}
1693
1694/* Startup Error handler to check if another window manager
1695 * is already running. */
1696int
1697xerrorstart(Display *dpy, XErrorEvent *ee) {
1698	otherwm = True;
1699	return -1;
1700}
1701
1702int
1703main(int argc, char *argv[]) {
1704	if(argc == 2 && !strcmp("-v", argv[1]))
1705		eprint("dwm-"VERSION", © 2006-2008 dwm engineers, see LICENSE for details\n");
1706	else if(argc != 1)
1707		eprint("usage: dwm [-v]\n");
1708
1709	setlocale(LC_CTYPE, "");
1710	if(!(dpy = XOpenDisplay(0)))
1711		eprint("dwm: cannot open display\n");
1712
1713	checkotherwm();
1714	setup();
1715	scan();
1716	run();
1717	cleanup();
1718
1719	XCloseDisplay(dpy);
1720	return 0;
1721}