text: /* See LICENSE file for copyright and license details.
   *
   * dynamic window manager is designed like any other X client as well. It is
   * driven through handling X events. In contrast to other X clients, a window
   * manager selects for SubstructureRedirectMask on the root window, to receive
   * events about window (dis-)appearance. Only one X connection at a time is
   * allowed to select for this event mask.
   *
   * The event handlers of dwm are organized in an array which is accessed
   * whenever a new event has been fetched. This allows event dispatching
   * in O(1) time.
   *
   * Each child of the root window is called a client, except windows which have
   * set the override_redirect flag. Clients are organized in a linked client
   * list on each monitor, the focus history is remembered through a stack list
   * on each monitor. Each client contains a bit array to indicate the tags of a
   * client.
   *
   * Keys and tagging rules are organized as arrays and defined in config.h.
   *
   * To understand everything else, start reading main().
   */
  #include <errno.h>
  #include <locale.h>
  #include <signal.h>
  #include <stdarg.h>
  #include <stdio.h>
  #include <stdlib.h>
  #include <string.h>
  #include <unistd.h>
  #include <sys/types.h>
  #include <sys/wait.h>
  #include <X11/cursorfont.h>
  #include <X11/keysym.h>
  #include <X11/Xatom.h>
  #include <X11/Xlib.h>
  #include <X11/Xproto.h>
  #include <X11/Xutil.h>
  #ifdef XINERAMA
  #include <X11/extensions/Xinerama.h>
  #endif /* XINERAMA */
  #include <X11/Xft/Xft.h>
  #include <pango/pango.h>
  
  #include "drw.h"
  #include "util.h"
  
  /* macros */
  #define BUTTONMASK              (ButtonPressMask|ButtonReleaseMask)
  #define CLEANMASK(mask)         (mask & ~(numlockmask|LockMask) & (ShiftMask|ControlMask|Mod1Mask|Mod2Mask|Mod3Mask|Mod4Mask|Mod5Mask))
  #define INTERSECT(x,y,w,h,m)    (MAX(0, MIN((x)+(w),(m)->wx+(m)->ww) - MAX((x),(m)->wx)) \
                                 * MAX(0, MIN((y)+(h),(m)->wy+(m)->wh) - MAX((y),(m)->wy)))
  #define ISVISIBLE(C)            ((C->tags & C->mon->tagset[C->mon->seltags]))
  #define LENGTH(X)               (sizeof X / sizeof X[0])
  #define MOUSEMASK               (BUTTONMASK|PointerMotionMask)
  #define WIDTH(X)                ((X)->w + 2 * (X)->bw)
  #define HEIGHT(X)               ((X)->h + 2 * (X)->bw)
  #define TAGMASK                 ((1 << LENGTH(tags)) - 1)
  #define TEXTW(X)                (drw_font_getwidth(drw, (X), False) + lrpad)
  #define TEXTWM(X)                (drw_font_getwidth(drw, (X), True) + lrpad)
  
  #define SYSTEM_TRAY_REQUEST_DOCK    0
  
  /* XEMBED messages */
  #define XEMBED_EMBEDDED_NOTIFY      0
  #define XEMBED_WINDOW_ACTIVATE      1
  #define XEMBED_FOCUS_IN             4
  #define XEMBED_MODALITY_ON         10
  
  #define XEMBED_MAPPED              (1 << 0)
  #define XEMBED_WINDOW_ACTIVATE      1
  #define XEMBED_WINDOW_DEACTIVATE    2
  
  #define VERSION_MAJOR               0
  #define VERSION_MINOR               0
  #define XEMBED_EMBEDDED_VERSION (VERSION_MAJOR << 16) | VERSION_MINOR
  
  /* enums */
  enum { CurNormal, CurResize, CurMove, CurLast }; /* cursor */
  enum { SchemeNorm, SchemeSel, SchemeStatus, SchemeTagsSel, SchemeTagsNorm, SchemeInfoSel, SchemeInfoNorm }; /* color schemes */
  enum { NetSupported, NetWMName, NetWMState, NetWMCheck,
         NetSystemTray, NetSystemTrayOP, NetSystemTrayOrientation, NetSystemTrayOrientationHorz,
         NetWMFullscreen, NetActiveWindow, NetWMWindowType,
         NetWMWindowTypeDialog, NetClientList, NetLast }; /* EWMH atoms */
  enum { Manager, Xembed, XembedInfo, XLast }; /* Xembed atoms */
  enum { WMProtocols, WMDelete, WMState, WMTakeFocus, WMLast }; /* default atoms */
  enum { ClkTagBar, ClkLtSymbol, ClkStatusText, ClkWinTitle,
         ClkClientWin, ClkRootWin, ClkLast }; /* clicks */
  
  typedef union {
  	int i;
  	unsigned int ui;
  	float f;
  	const void *v;
  } Arg;
  
  typedef struct {
  	unsigned int click;
  	unsigned int mask;
  	unsigned int button;
  	void (*func)(const Arg *arg);
  	const Arg arg;
  } Button;
  
  typedef struct Monitor Monitor;
  typedef struct Client Client;
  struct Client {
  	char name[256];
  	float mina, maxa;
  	float cfact;
  	int x, y, w, h;
  	int oldx, oldy, oldw, oldh;
  	int basew, baseh, incw, inch, maxw, maxh, minw, minh;
  	int bw, oldbw;
  	unsigned int tags;
  	int isfixed, isfloating, isurgent, neverfocus, oldstate, isfullscreen;
  	Client *next;
  	Client *snext;
  	Monitor *mon;
  	Window win;
  };
  
  typedef struct {
  	unsigned int mod;
  	KeySym keysym;
  	void (*func)(const Arg *);
  	const Arg arg;
  } Key;
  
  typedef struct {
  	const char *symbol;
  	void (*arrange)(Monitor *);
  } Layout;
  
  struct Monitor {
  	char ltsymbol[16];
  	float mfact;
  	int nmaster;
  	int num;
  	int by;               /* bar geometry */
  	int mx, my, mw, mh;   /* screen size */
  	int wx, wy, ww, wh;   /* window area  */
  	int gappih;           /* horizontal gap between windows */
  	int gappiv;           /* vertical gap between windows */
  	int gappoh;           /* horizontal outer gaps */
  	int gappov;           /* vertical outer gaps */
  	unsigned int seltags;
  	unsigned int sellt;
  	unsigned int tagset[2];
  	int showbar;
  	int topbar;
  	Client *clients;
  	Client *sel;
  	Client *stack;
  	Monitor *next;
  	Window barwin;
  	const Layout *lt[2];
  };
  
  typedef struct {
  	const char *class;
  	const char *instance;
  	const char *title;
  	unsigned int tags;
  	int isfloating;
  	int monitor;
  } Rule;
  
  typedef struct Systray   Systray;
  struct Systray {
  	Window win;
  	Client *icons;
  };
  
  /* function declarations */
  static void applyrules(Client *c);
  static int applysizehints(Client *c, int *x, int *y, int *w, int *h, int interact);
  static void arrange(Monitor *m);
  static void arrangemon(Monitor *m);
  static void attach(Client *c);
  static void attachstack(Client *c);
  static void buttonpress(XEvent *e);
  static void checkotherwm(void);
  static void cleanup(void);
  static void cleanupmon(Monitor *mon);
  static void clientmessage(XEvent *e);
  static void configure(Client *c);
  static void configurenotify(XEvent *e);
  static void configurerequest(XEvent *e);
  static Monitor *createmon(void);
  static void destroynotify(XEvent *e);
  static void detach(Client *c);
  static void detachstack(Client *c);
  static Monitor *dirtomon(int dir);
  static void drawbar(Monitor *m);
  static void drawbars(void);
  static void enternotify(XEvent *e);
  static void expose(XEvent *e);
  static void focus(Client *c);
  static void focusin(XEvent *e);
  static void focusmon(const Arg *arg);
  static void focusstack(const Arg *arg);
  static int getrootptr(int *x, int *y);
  static long getstate(Window w);
  static unsigned int getsystraywidth();
  static int gettextprop(Window w, Atom atom, char *text, unsigned int size);
  static void grabbuttons(Client *c, int focused);
  static void grabkeys(void);
  static void incnmaster(const Arg *arg);
  static void keypress(XEvent *e);
  static void killclient(const Arg *arg);
  static void manage(Window w, XWindowAttributes *wa);
  static void mappingnotify(XEvent *e);
  static void maprequest(XEvent *e);
  static void monocle(Monitor *m);
  static void motionnotify(XEvent *e);
  static void movemouse(const Arg *arg);
  static Client *nexttiled(Client *c);
  static void pop(Client *);
  static void propertynotify(XEvent *e);
  static void quit(const Arg *arg);
  static Monitor *recttomon(int x, int y, int w, int h);
  static void removesystrayicon(Client *i);
  static void resize(Client *c, int x, int y, int w, int h, int interact);
  static void resizebarwin(Monitor *m);
  static void resizeclient(Client *c, int x, int y, int w, int h);
  static void resizemouse(const Arg *arg);
  static void resizerequest(XEvent *e);
  static void restack(Monitor *m);
  static void run(void);
  static void scan(void);
  static int sendevent(Window w, Atom proto, int m, long d0, long d1, long d2, long d3, long d4);
  static void sendmon(Client *c, Monitor *m);
  static void setclientstate(Client *c, long state);
  static void setfocus(Client *c);
  static void setfullscreen(Client *c, int fullscreen);
  static void setlayout(const Arg *arg);
  static void setcfact(const Arg *arg);
  static void setmfact(const Arg *arg);
  static void setup(void);
  static void seturgent(Client *c, int urg);
  static void showhide(Client *c);
  static void sigchld(int unused);
  static void spawn(const Arg *arg);
  static Monitor *systraytomon(Monitor *m);
  static void tag(const Arg *arg);
  static void tagmon(const Arg *arg);
  static void togglebar(const Arg *arg);
  static void togglefloating(const Arg *arg);
  static void toggletag(const Arg *arg);
  static void toggleview(const Arg *arg);
  static void unfocus(Client *c, int setfocus);
  static void unmanage(Client *c, int destroyed);
  static void unmapnotify(XEvent *e);
  static void updatebarpos(Monitor *m);
  static void updatebars(void);
  static void updateclientlist(void);
  static int updategeom(void);
  static void updatenumlockmask(void);
  static void updatesizehints(Client *c);
  static void updatestatus(void);
  static void updatesystray(void);
  static void updatesystrayicongeom(Client *i, int w, int h);
  static void updatesystrayiconstate(Client *i, XPropertyEvent *ev);
  static void updatetitle(Client *c);
  static void updatewindowtype(Client *c);
  static void updatewmhints(Client *c);
  static void view(const Arg *arg);
  static Client *wintoclient(Window w);
  static Monitor *wintomon(Window w);
  static Client *wintosystrayicon(Window w);
  static int xerror(Display *dpy, XErrorEvent *ee);
  static int xerrordummy(Display *dpy, XErrorEvent *ee);
  static int xerrorstart(Display *dpy, XErrorEvent *ee);
  static void zoom(const Arg *arg);
  
  /* variables */
  static Systray *systray =  NULL;
  static const char broken[] = "broken";
  static char stext[512];
  static int screen;
  static int sw, sh;           /* X display screen geometry width, height */
  static int bh, blw = 0;      /* bar geometry */
  static int lrpad;            /* sum of left and right padding for text */
  static int (*xerrorxlib)(Display *, XErrorEvent *);
  static unsigned int numlockmask = 0;
  static void (*handler[LASTEvent]) (XEvent *) = {
  	[ButtonPress] = buttonpress,
  	[ClientMessage] = clientmessage,
  	[ConfigureRequest] = configurerequest,
  	[ConfigureNotify] = configurenotify,
  	[DestroyNotify] = destroynotify,
  	[EnterNotify] = enternotify,
  	[Expose] = expose,
  	[FocusIn] = focusin,
  	[KeyPress] = keypress,
  	[MappingNotify] = mappingnotify,
  	[MapRequest] = maprequest,
  	[MotionNotify] = motionnotify,
  	[PropertyNotify] = propertynotify,
  	[ResizeRequest] = resizerequest,
  	[UnmapNotify] = unmapnotify
  };
  static Atom wmatom[WMLast], netatom[NetLast], xatom[XLast];
  static int running = 1;
  static Cur *cursor[CurLast];
  static Clr **scheme;
  static Display *dpy;
  static Drw *drw;
  static Monitor *mons, *selmon;
  static Window root, wmcheckwin;
  
  /* configuration, allows nested code to access above variables */
  #include "config.h"
  
  /* compile-time check if all tags fit into an unsigned int bit array. */
  struct NumTags { char limitexceeded[LENGTH(tags) > 31 ? -1 : 1]; };
  
  /* function implementations */
  void
  applyrules(Client *c)
  {
  	const char *class, *instance;
  	unsigned int i;
  	const Rule *r;
  	Monitor *m;
  	XClassHint ch = { NULL, NULL };
  
  	/* rule matching */
  	c->isfloating = 0;
  	c->tags = 0;
  	XGetClassHint(dpy, c->win, &ch);
  	class    = ch.res_class ? ch.res_class : broken;
  	instance = ch.res_name  ? ch.res_name  : broken;
  
  	for (i = 0; i < LENGTH(rules); i++) {
  		r = &rules[i];
  		if ((!r->title || strstr(c->name, r->title))
  		&& (!r->class || strstr(class, r->class))
  		&& (!r->instance || strstr(instance, r->instance)))
  		{
  			c->isfloating = r->isfloating;
  			c->tags |= r->tags;
  			for (m = mons; m && m->num != r->monitor; m = m->next);
  			if (m)
  				c->mon = m;
  		}
  	}
  	if (ch.res_class)
  		XFree(ch.res_class);
  	if (ch.res_name)
  		XFree(ch.res_name);
  	c->tags = c->tags & TAGMASK ? c->tags & TAGMASK : c->mon->tagset[c->mon->seltags];
  }
  
  int
  applysizehints(Client *c, int *x, int *y, int *w, int *h, int interact)
  {
  	int baseismin;
  	Monitor *m = c->mon;
  
  	/* set minimum possible */
  	*w = MAX(1, *w);
  	*h = MAX(1, *h);
  	if (interact) {
  		if (*x > sw)
  			*x = sw - WIDTH(c);
  		if (*y > sh)
  			*y = sh - HEIGHT(c);
  		if (*x + *w + 2 * c->bw < 0)
  			*x = 0;
  		if (*y + *h + 2 * c->bw < 0)
  			*y = 0;
  	} else {
  		if (*x >= m->wx + m->ww)
  			*x = m->wx + m->ww - WIDTH(c);
  		if (*y >= m->wy + m->wh)
  			*y = m->wy + m->wh - HEIGHT(c);
  		if (*x + *w + 2 * c->bw <= m->wx)
  			*x = m->wx;
  		if (*y + *h + 2 * c->bw <= m->wy)
  			*y = m->wy;
  	}
  	if (*h < bh)
  		*h = bh;
  	if (*w < bh)
  		*w = bh;
  	if (resizehints || c->isfloating || !c->mon->lt[c->mon->sellt]->arrange) {
  		/* see last two sentences in ICCCM 4.1.2.3 */
  		baseismin = c->basew == c->minw && c->baseh == c->minh;
  		if (!baseismin) { /* temporarily remove base dimensions */
  			*w -= c->basew;
  			*h -= c->baseh;
  		}
  		/* adjust for aspect limits */
  		if (c->mina > 0 && c->maxa > 0) {
  			if (c->maxa < (float)*w / *h)
  				*w = *h * c->maxa + 0.5;
  			else if (c->mina < (float)*h / *w)
  				*h = *w * c->mina + 0.5;
  		}
  		if (baseismin) { /* increment calculation requires this */
  			*w -= c->basew;
  			*h -= c->baseh;
  		}
  		/* adjust for increment value */
  		if (c->incw)
  			*w -= *w % c->incw;
  		if (c->inch)
  			*h -= *h % c->inch;
  		/* restore base dimensions */
  		*w = MAX(*w + c->basew, c->minw);
  		*h = MAX(*h + c->baseh, c->minh);
  		if (c->maxw)
  			*w = MIN(*w, c->maxw);
  		if (c->maxh)
  			*h = MIN(*h, c->maxh);
  	}
  	return *x != c->x || *y != c->y || *w != c->w || *h != c->h;
  }
  
  void
  arrange(Monitor *m)
  {
  	if (m)
  		showhide(m->stack);
  	else for (m = mons; m; m = m->next)
  		showhide(m->stack);
  	if (m) {
  		arrangemon(m);
  		restack(m);
  	} else for (m = mons; m; m = m->next)
  		arrangemon(m);
  }
  
  void
  arrangemon(Monitor *m)
  {
  	strncpy(m->ltsymbol, m->lt[m->sellt]->symbol, sizeof m->ltsymbol);
  	if (m->lt[m->sellt]->arrange)
  		m->lt[m->sellt]->arrange(m);
  }
  
  void
  attach(Client *c)
  {
  	c->next = c->mon->clients;
  	c->mon->clients = c;
  }
  
  void
  attachstack(Client *c)
  {
  	c->snext = c->mon->stack;
  	c->mon->stack = c;
  }
  
  void
  buttonpress(XEvent *e)
  {
  	unsigned int i, x, click;
  	Arg arg = {0};
  	Client *c;
  	Monitor *m;
  	XButtonPressedEvent *ev = &e->xbutton;
  
  	click = ClkRootWin;
  	/* focus monitor if necessary */
  	if ((m = wintomon(ev->window)) && m != selmon) {
  		unfocus(selmon->sel, 1);
  		selmon = m;
  		focus(NULL);
  	}
  	if (ev->window == selmon->barwin) {
  		i = x = 0;
  		do
  			x += TEXTW(tags[i]);
  		while (ev->x >= x && ++i < LENGTH(tags));
  		if (i < LENGTH(tags)) {
  			click = ClkTagBar;
  			arg.ui = 1 << i;
  		} else if (ev->x < x + blw)
  			click = ClkLtSymbol;
  		else if (ev->x > selmon->ww - TEXTWM(stext))
  			click = ClkStatusText;
  		else
  			click = ClkWinTitle;
  	} else if ((c = wintoclient(ev->window))) {
  		focus(c);
  		restack(selmon);
  		XAllowEvents(dpy, ReplayPointer, CurrentTime);
  		click = ClkClientWin;
  	}
  	for (i = 0; i < LENGTH(buttons); i++)
  		if (click == buttons[i].click && buttons[i].func && buttons[i].button == ev->button
  		&& CLEANMASK(buttons[i].mask) == CLEANMASK(ev->state))
  			buttons[i].func(click == ClkTagBar && buttons[i].arg.i == 0 ? &arg : &buttons[i].arg);
  }
  
  void
  checkotherwm(void)
  {
  	xerrorxlib = XSetErrorHandler(xerrorstart);
  	/* this causes an error if some other window manager is running */
  	XSelectInput(dpy, DefaultRootWindow(dpy), SubstructureRedirectMask);
  	XSync(dpy, False);
  	XSetErrorHandler(xerror);
  	XSync(dpy, False);
  }
  
  void
  cleanup(void)
  {
  	Arg a = {.ui = ~0};
  	Layout foo = { "", NULL };
  	Monitor *m;
  	size_t i;
  
  	view(&a);
  	selmon->lt[selmon->sellt] = &foo;
  	for (m = mons; m; m = m->next)
  		while (m->stack)
  			unmanage(m->stack, 0);
  	XUngrabKey(dpy, AnyKey, AnyModifier, root);
  	while (mons)
  		cleanupmon(mons);
  	if (showsystray) {
  		XUnmapWindow(dpy, systray->win);
  		XDestroyWindow(dpy, systray->win);
  		free(systray);
  	}
  	for (i = 0; i < CurLast; i++)
  		drw_cur_free(drw, cursor[i]);
  	for (i = 0; i < LENGTH(colors); i++)
  		free(scheme[i]);
  	XDestroyWindow(dpy, wmcheckwin);
  	drw_free(drw);
  	XSync(dpy, False);
  	XSetInputFocus(dpy, PointerRoot, RevertToPointerRoot, CurrentTime);
  	XDeleteProperty(dpy, root, netatom[NetActiveWindow]);
  }
  
  void
  cleanupmon(Monitor *mon)
  {
  	Monitor *m;
  
  	if (mon == mons)
  		mons = mons->next;
  	else {
  		for (m = mons; m && m->next != mon; m = m->next);
  		m->next = mon->next;
  	}
  	XUnmapWindow(dpy, mon->barwin);
  	XDestroyWindow(dpy, mon->barwin);
  	free(mon);
  }
  
  void
  clientmessage(XEvent *e)
  {
  	XWindowAttributes wa;
  	XSetWindowAttributes swa;
  	XClientMessageEvent *cme = &e->xclient;
  	Client *c = wintoclient(cme->window);
  
  	if (showsystray && cme->window == systray->win && cme->message_type == netatom[NetSystemTrayOP]) {
  		/* add systray icons */
  		if (cme->data.l[1] == SYSTEM_TRAY_REQUEST_DOCK) {
  			if (!(c = (Client *)calloc(1, sizeof(Client))))
  				die("fatal: could not malloc() %u bytes\n", sizeof(Client));
  			if (!(c->win = cme->data.l[2])) {
  				free(c);
  				return;
  			}
  			c->mon = selmon;
  			c->next = systray->icons;
  			systray->icons = c;
  			if (!XGetWindowAttributes(dpy, c->win, &wa)) {
  				/* use sane defaults */
  				wa.width = bh;
  				wa.height = bh;
  				wa.border_width = 0;
  			}
  			c->x = c->oldx = c->y = c->oldy = 0;
  			c->w = c->oldw = wa.width;
  			c->h = c->oldh = wa.height;
  			c->oldbw = wa.border_width;
  			c->bw = 0;
  			c->isfloating = True;
  			/* reuse tags field as mapped status */
  			c->tags = 1;
  			updatesizehints(c);
  			updatesystrayicongeom(c, wa.width, wa.height);
  			XAddToSaveSet(dpy, c->win);
  			XSelectInput(dpy, c->win, StructureNotifyMask | PropertyChangeMask | ResizeRedirectMask);
  			XReparentWindow(dpy, c->win, systray->win, 0, 0);
  			/* use parents background color */
  			swa.background_pixel  = scheme[SchemeNorm][ColBg].pixel;
  			XChangeWindowAttributes(dpy, c->win, CWBackPixel, &swa);
  			sendevent(c->win, netatom[Xembed], StructureNotifyMask, CurrentTime, XEMBED_EMBEDDED_NOTIFY, 0 , systray->win, XEMBED_EMBEDDED_VERSION);
  			/* FIXME not sure if I have to send these events, too */
  			sendevent(c->win, netatom[Xembed], StructureNotifyMask, CurrentTime, XEMBED_FOCUS_IN, 0 , systray->win, XEMBED_EMBEDDED_VERSION);
  			sendevent(c->win, netatom[Xembed], StructureNotifyMask, CurrentTime, XEMBED_WINDOW_ACTIVATE, 0 , systray->win, XEMBED_EMBEDDED_VERSION);
  			sendevent(c->win, netatom[Xembed], StructureNotifyMask, CurrentTime, XEMBED_MODALITY_ON, 0 , systray->win, XEMBED_EMBEDDED_VERSION);
  			XSync(dpy, False);
  			resizebarwin(selmon);
  			updatesystray();
  			setclientstate(c, NormalState);
  		}
  		return;
  	}
  	if (!c)
  		return;
  	if (cme->message_type == netatom[NetWMState]) {
  		if (cme->data.l[1] == netatom[NetWMFullscreen]
  		|| cme->data.l[2] == netatom[NetWMFullscreen])
  			setfullscreen(c, (cme->data.l[0] == 1 /* _NET_WM_STATE_ADD    */
  				|| (cme->data.l[0] == 2 /* _NET_WM_STATE_TOGGLE */ && !c->isfullscreen)));
  	} else if (cme->message_type == netatom[NetActiveWindow]) {
  		if (c != selmon->sel && !c->isurgent)
  			seturgent(c, 1);
  	}
  }
  
  void
  configure(Client *c)
  {
  	XConfigureEvent ce;
  
  	ce.type = ConfigureNotify;
  	ce.display = dpy;
  	ce.event = c->win;
  	ce.window = c->win;
  	ce.x = c->x;
  	ce.y = c->y;
  	ce.width = c->w;
  	ce.height = c->h;
  	ce.border_width = c->bw;
  	ce.above = None;
  	ce.override_redirect = False;
  	XSendEvent(dpy, c->win, False, StructureNotifyMask, (XEvent *)&ce);
  }
  
  void
  configurenotify(XEvent *e)
  {
  	Monitor *m;
  	Client *c;
  	XConfigureEvent *ev = &e->xconfigure;
  	int dirty;
  
  	/* TODO: updategeom handling sucks, needs to be simplified */
  	if (ev->window == root) {
  		dirty = (sw != ev->width || sh != ev->height);
  		sw = ev->width;
  		sh = ev->height;
  		if (updategeom() || dirty) {
  			drw_resize(drw, sw, bh);
  			updatebars();
  			for (m = mons; m; m = m->next) {
  				for (c = m->clients; c; c = c->next)
  					if (c->isfullscreen)
  						resizeclient(c, m->mx, m->my, m->mw, m->mh);
  				resizebarwin(m);
  			}
  			focus(NULL);
  			arrange(NULL);
  		}
  	}
  }
  
  void
  configurerequest(XEvent *e)
  {
  	Client *c;
  	Monitor *m;
  	XConfigureRequestEvent *ev = &e->xconfigurerequest;
  	XWindowChanges wc;
  
  	if ((c = wintoclient(ev->window))) {
  		if (ev->value_mask & CWBorderWidth)
  			c->bw = ev->border_width;
  		else if (c->isfloating || !selmon->lt[selmon->sellt]->arrange) {
  			m = c->mon;
  			if (ev->value_mask & CWX) {
  				c->oldx = c->x;
  				c->x = m->mx + ev->x;
  			}
  			if (ev->value_mask & CWY) {
  				c->oldy = c->y;
  				c->y = m->my + ev->y;
  			}
  			if (ev->value_mask & CWWidth) {
  				c->oldw = c->w;
  				c->w = ev->width;
  			}
  			if (ev->value_mask & CWHeight) {
  				c->oldh = c->h;
  				c->h = ev->height;
  			}
  			if ((c->x + c->w) > m->mx + m->mw && c->isfloating)
  				c->x = m->mx + (m->mw / 2 - WIDTH(c) / 2); /* center in x direction */
  			if ((c->y + c->h) > m->my + m->mh && c->isfloating)
  				c->y = m->my + (m->mh / 2 - HEIGHT(c) / 2); /* center in y direction */
  			if ((ev->value_mask & (CWX|CWY)) && !(ev->value_mask & (CWWidth|CWHeight)))
  				configure(c);
  			if (ISVISIBLE(c))
  				XMoveResizeWindow(dpy, c->win, c->x, c->y, c->w, c->h);
  		} else
  			configure(c);
  	} else {
  		wc.x = ev->x;
  		wc.y = ev->y;
  		wc.width = ev->width;
  		wc.height = ev->height;
  		wc.border_width = ev->border_width;
  		wc.sibling = ev->above;
  		wc.stack_mode = ev->detail;
  		XConfigureWindow(dpy, ev->window, ev->value_mask, &wc);
  	}
  	XSync(dpy, False);
  }
  
  Monitor *
  createmon(void)
  {
  	Monitor *m;
  
  	m = ecalloc(1, sizeof(Monitor));
  	m->tagset[0] = m->tagset[1] = 1;
  	m->mfact = mfact;
  	m->nmaster = nmaster;
  	m->showbar = showbar;
  	m->topbar = topbar;
  	m->gappih = gappih;
  	m->gappiv = gappiv;
  	m->gappoh = gappoh;
  	m->gappov = gappov;
  	m->lt[0] = &layouts[0];
  	m->lt[1] = &layouts[1 % LENGTH(layouts)];
  	strncpy(m->ltsymbol, layouts[0].symbol, sizeof m->ltsymbol);
  	return m;
  }
  
  void
  destroynotify(XEvent *e)
  {
  	Client *c;
  	XDestroyWindowEvent *ev = &e->xdestroywindow;
  
  	if ((c = wintoclient(ev->window)))
  		unmanage(c, 1);
  	else if ((c = wintosystrayicon(ev->window))) {
  		removesystrayicon(c);
  		resizebarwin(selmon);
  		updatesystray();
  	}
  }
  
  void
  detach(Client *c)
  {
  	Client **tc;
  
  	for (tc = &c->mon->clients; *tc && *tc != c; tc = &(*tc)->next);
  	*tc = c->next;
  }
  
  void
  detachstack(Client *c)
  {
  	Client **tc, *t;
  
  	for (tc = &c->mon->stack; *tc && *tc != c; tc = &(*tc)->snext);
  	*tc = c->snext;
  
  	if (c == c->mon->sel) {
  		for (t = c->mon->stack; t && !ISVISIBLE(t); t = t->snext);
  		c->mon->sel = t;
  	}
  }
  
  Monitor *
  dirtomon(int dir)
  {
  	Monitor *m = NULL;
  
  	if (dir > 0) {
  		if (!(m = selmon->next))
  			m = mons;
  	} else if (selmon == mons)
  		for (m = mons; m->next; m = m->next);
  	else
  		for (m = mons; m->next != selmon; m = m->next);
  	return m;
  }
  
  void
  drawbar(Monitor *m)
  {
  	int x, w, sw = 0, stw = 0;
  	int boxs = drw->font->h / 9;
  	int boxw = drw->font->h / 6 + 2;
  	unsigned int i, occ = 0, urg = 0;
  	Client *c;
  
  	/* draw status first so it can be overdrawn by tags later */
  	if (m == selmon) { /* status is only drawn on selected monitor */
  		drw_setscheme(drw, scheme[SchemeStatus]);
  		sw = TEXTWM(stext) - lrpad / 2 + 2; /* 2px extra right padding */
  		drw_text(drw, m->ww - sw - stw, 0, sw, bh, lrpad / 2 - 2, stext, 0, True);
  	}
  
  	resizebarwin(m);
  	for (c = m->clients; c; c = c->next) {
  		occ |= c->tags;
  		if (c->isurgent)
  			urg |= c->tags;
  	}
  	x = 0;
  	for (i = 0; i < LENGTH(tags); i++) {
  
  		w = TEXTW(tags[i]);
  		drw_setscheme(drw, scheme[m->tagset[m->seltags] & 1 << i ? SchemeTagsSel : SchemeTagsNorm]);
  		drw_text(drw, x, 0, w, bh, lrpad / 2, tags[i], urg & 1 << i, False);
  		x += w;
  	}
  	w = blw = TEXTW(m->ltsymbol);
  	drw_setscheme(drw, scheme[SchemeTagsNorm]);
  	x = drw_text(drw, x, 0, w, bh, lrpad / 2, m->ltsymbol, 0, False);
  
  	if ((w = m->ww - sw - stw - x) > bh) {
  		if (m->sel) {
  			drw_setscheme(drw, scheme[m == selmon ? SchemeInfoSel : SchemeInfoNorm]);
  			drw_text(drw, x, 0, w, bh, lrpad / 2, m->sel->name, 0, False);
  			if (m->sel->isfloating)
  				drw_rect(drw, x + boxs, boxs, boxw, boxw, m->sel->isfixed, 0);
  		} else {
  			drw_setscheme(drw, scheme[SchemeInfoNorm]);
  			drw_rect(drw, x, 0, w, bh, 1, 1);
  		}
  	}
  	drw_map(drw, m->barwin, 0, 0, m->ww - stw, bh);
  }
  
  void
  drawbars(void)
  {
  	Monitor *m;
  
  	for (m = mons; m; m = m->next)
  		drawbar(m);
  }
  
  void
  enternotify(XEvent *e)
  {
  	Client *c;
  	Monitor *m;
  	XCrossingEvent *ev = &e->xcrossing;
  
  	if ((ev->mode != NotifyNormal || ev->detail == NotifyInferior) && ev->window != root)
  		return;
  	c = wintoclient(ev->window);
  	m = c ? c->mon : wintomon(ev->window);
  	if (m != selmon) {
  		unfocus(selmon->sel, 1);
  		selmon = m;
  	} else if (!c || c == selmon->sel)
  		return;
  	focus(c);
  }
  
  void
  expose(XEvent *e)
  {
  	Monitor *m;
  	XExposeEvent *ev = &e->xexpose;
  
  	if (ev->count == 0 && (m = wintomon(ev->window))) {
  		drawbar(m);
  		if (m == selmon)
  			updatesystray();
  	}
  }
  
  void
  focus(Client *c)
  {
  	if (!c || !ISVISIBLE(c))
  		for (c = selmon->stack; c && !ISVISIBLE(c); c = c->snext);
  	if (selmon->sel && selmon->sel != c)
  		unfocus(selmon->sel, 0);
  	if (c) {
  		if (c->mon != selmon)
  			selmon = c->mon;
  		if (c->isurgent)
  			seturgent(c, 0);
  		detachstack(c);
  		attachstack(c);
  		grabbuttons(c, 1);
  		XSetWindowBorder(dpy, c->win, scheme[SchemeSel][ColBorder].pixel);
  		setfocus(c);
  	} else {
  		XSetInputFocus(dpy, root, RevertToPointerRoot, CurrentTime);
  		XDeleteProperty(dpy, root, netatom[NetActiveWindow]);
  	}
  	selmon->sel = c;
  	drawbars();
  }
  
  /* there are some broken focus acquiring clients needing extra handling */
  void
  focusin(XEvent *e)
  {
  	XFocusChangeEvent *ev = &e->xfocus;
  
  	if (selmon->sel && ev->window != selmon->sel->win)
  		setfocus(selmon->sel);
  }
  
  void
  focusmon(const Arg *arg)
  {
  	Monitor *m;
  
  	if (!mons->next)
  		return;
  	if ((m = dirtomon(arg->i)) == selmon)
  		return;
  	unfocus(selmon->sel, 0);
  	selmon = m;
  	focus(NULL);
  }
  
  void
  focusstack(const Arg *arg)
  {
  	Client *c = NULL, *i;
  
  	if (!selmon->sel)
  		return;
  	if (arg->i > 0) {
  		for (c = selmon->sel->next; c && !ISVISIBLE(c); c = c->next);
  		if (!c)
  			for (c = selmon->clients; c && !ISVISIBLE(c); c = c->next);
  	} else {
  		for (i = selmon->clients; i != selmon->sel; i = i->next)
  			if (ISVISIBLE(i))
  				c = i;
  		if (!c)
  			for (; i; i = i->next)
  				if (ISVISIBLE(i))
  					c = i;
  	}
  	if (c) {
  		focus(c);
  		restack(selmon);
  	}
  }
  
  Atom
  getatomprop(Client *c, Atom prop)
  {
  	int di;
  	unsigned long dl;
  	unsigned char *p = NULL;
  	Atom da, atom = None;
  	/* FIXME getatomprop should return the number of items and a pointer to
  	 * the stored data instead of this workaround */
  	Atom req = XA_ATOM;
  	if (prop == xatom[XembedInfo])
  		req = xatom[XembedInfo];
  
  	if (XGetWindowProperty(dpy, c->win, prop, 0L, sizeof atom, False, req,
  		&da, &di, &dl, &dl, &p) == Success && p) {
  		atom = *(Atom *)p;
  		if (da == xatom[XembedInfo] && dl == 2)
  			atom = ((Atom *)p)[1];
  		XFree(p);
  	}
  	return atom;
  }
  
  int
  getrootptr(int *x, int *y)
  {
  	int di;
  	unsigned int dui;
  	Window dummy;
  
  	return XQueryPointer(dpy, root, &dummy, &dummy, x, y, &di, &di, &dui);
  }
  
  long
  getstate(Window w)
  {
  	int format;
  	long result = -1;
  	unsigned char *p = NULL;
  	unsigned long n, extra;
  	Atom real;
  
  	if (XGetWindowProperty(dpy, w, wmatom[WMState], 0L, 2L, False, wmatom[WMState],
  		&real, &format, &n, &extra, (unsigned char **)&p) != Success)
  		return -1;
  	if (n != 0)
  		result = *p;
  	XFree(p);
  	return result;
  }
  
  unsigned int
  getsystraywidth()
  {
  	unsigned int w = 0;
  	Client *i;
  	if(showsystray)
  		for(i = systray->icons; i; w += i->w + systrayspacing, i = i->next) ;
  	return w ? w + systrayspacing : 1;
  }
  
  int
  gettextprop(Window w, Atom atom, char *text, unsigned int size)
  {
  	char **list = NULL;
  	int n;
  	XTextProperty name;
  
  	if (!text || size == 0)
  		return 0;
  	text[0] = '\0';
  	if (!XGetTextProperty(dpy, w, &name, atom) || !name.nitems)
  		return 0;
  	if (name.encoding == XA_STRING)
  		strncpy(text, (char *)name.value, size - 1);
  	else {
  		if (XmbTextPropertyToTextList(dpy, &name, &list, &n) >= Success && n > 0 && *list) {
  			strncpy(text, *list, size - 1);
  			XFreeStringList(list);
  		}
  	}
  	text[size - 1] = '\0';
  	XFree(name.value);
  	return 1;
  }
  
  void
  grabbuttons(Client *c, int focused)
  {
  	updatenumlockmask();
  	{
  		unsigned int i, j;
  		unsigned int modifiers[] = { 0, LockMask, numlockmask, numlockmask|LockMask };
  		XUngrabButton(dpy, AnyButton, AnyModifier, c->win);
  		if (!focused)
  			XGrabButton(dpy, AnyButton, AnyModifier, c->win, False,
  				BUTTONMASK, GrabModeSync, GrabModeSync, None, None);
  		for (i = 0; i < LENGTH(buttons); i++)
  			if (buttons[i].click == ClkClientWin)
  				for (j = 0; j < LENGTH(modifiers); j++)
  					XGrabButton(dpy, buttons[i].button,
  						buttons[i].mask | modifiers[j],
  						c->win, False, BUTTONMASK,
  						GrabModeAsync, GrabModeSync, None, None);
  	}
  }
  
  void
  grabkeys(void)
  {
  	updatenumlockmask();
  	{
  		unsigned int i, j;
  		unsigned int modifiers[] = { 0, LockMask, numlockmask, numlockmask|LockMask };
  		KeyCode code;
  
  		XUngrabKey(dpy, AnyKey, AnyModifier, root);
  		for (i = 0; i < LENGTH(keys); i++)
  			if ((code = XKeysymToKeycode(dpy, keys[i].keysym)))
  				for (j = 0; j < LENGTH(modifiers); j++)
  					XGrabKey(dpy, code, keys[i].mod | modifiers[j], root,
  						True, GrabModeAsync, GrabModeAsync);
  	}
  }
  
  void
  incnmaster(const Arg *arg)
  {
  	selmon->nmaster = MAX(selmon->nmaster + arg->i, 0);
  	arrange(selmon);
  }
  
  #ifdef XINERAMA
  static int
  isuniquegeom(XineramaScreenInfo *unique, size_t n, XineramaScreenInfo *info)
  {
  	while (n--)
  		if (unique[n].x_org == info->x_org && unique[n].y_org == info->y_org
  		&& unique[n].width == info->width && unique[n].height == info->height)
  			return 0;
  	return 1;
  }
  #endif /* XINERAMA */
  
  void
  keypress(XEvent *e)
  {
  	unsigned int i;
  	KeySym keysym;
  	XKeyEvent *ev;
  
  	ev = &e->xkey;
  	keysym = XKeycodeToKeysym(dpy, (KeyCode)ev->keycode, 0);
  	for (i = 0; i < LENGTH(keys); i++)
  		if (keysym == keys[i].keysym
  		&& CLEANMASK(keys[i].mod) == CLEANMASK(ev->state)
  		&& keys[i].func)
  			keys[i].func(&(keys[i].arg));
  }
  
  void
  killclient(const Arg *arg)
  {
  	if (!selmon->sel)
  		return;
  	if (!sendevent(selmon->sel->win, wmatom[WMDelete], NoEventMask, wmatom[WMDelete], CurrentTime, 0 , 0, 0)) {
  		XGrabServer(dpy);
  		XSetErrorHandler(xerrordummy);
  		XSetCloseDownMode(dpy, DestroyAll);
  		XKillClient(dpy, selmon->sel->win);
  		XSync(dpy, False);
  		XSetErrorHandler(xerror);
  		XUngrabServer(dpy);
  	}
  }
  
  void
  manage(Window w, XWindowAttributes *wa)
  {
  	Client *c, *t = NULL;
  	Window trans = None;
  	XWindowChanges wc;
  
  	c = ecalloc(1, sizeof(Client));
  	c->win = w;
  	/* geometry */
  	c->x = c->oldx = wa->x;
  	c->y = c->oldy = wa->y;
  	c->w = c->oldw = wa->width;
  	c->h = c->oldh = wa->height;
  	c->oldbw = wa->border_width;
  	c->cfact = 1.0;
  
  	updatetitle(c);
  	if (XGetTransientForHint(dpy, w, &trans) && (t = wintoclient(trans))) {
  		c->mon = t->mon;
  		c->tags = t->tags;
  	} else {
  		c->mon = selmon;
  		applyrules(c);
  	}
  
  	if (c->x + WIDTH(c) > c->mon->mx + c->mon->mw)
  		c->x = c->mon->mx + c->mon->mw - WIDTH(c);
  	if (c->y + HEIGHT(c) > c->mon->my + c->mon->mh)
  		c->y = c->mon->my + c->mon->mh - HEIGHT(c);
  	c->x = MAX(c->x, c->mon->mx);
  	/* only fix client y-offset, if the client center might cover the bar */
  	c->y = MAX(c->y, ((c->mon->by == c->mon->my) && (c->x + (c->w / 2) >= c->mon->wx)
  		&& (c->x + (c->w / 2) < c->mon->wx + c->mon->ww)) ? bh : c->mon->my);
  	c->bw = borderpx;
  
  	wc.border_width = c->bw;
  	XConfigureWindow(dpy, w, CWBorderWidth, &wc);
  	XSetWindowBorder(dpy, w, scheme[SchemeNorm][ColBorder].pixel);
  	configure(c); /* propagates border_width, if size doesn't change */
  	updatewindowtype(c);
  	updatesizehints(c);
  	updatewmhints(c);
  	c->x = c->mon->mx + (c->mon->mw - WIDTH(c)) / 2;
  	c->y = c->mon->my + (c->mon->mh - HEIGHT(c)) / 2;
  	XSelectInput(dpy, w, EnterWindowMask|FocusChangeMask|PropertyChangeMask|StructureNotifyMask);
  	grabbuttons(c, 0);
  	if (!c->isfloating)
  		c->isfloating = c->oldstate = trans != None || c->isfixed;
  	if (c->isfloating)
  		XRaiseWindow(dpy, c->win);
  	attach(c);
  	attachstack(c);
  	XChangeProperty(dpy, root, netatom[NetClientList], XA_WINDOW, 32, PropModeAppend,
  		(unsigned char *) &(c->win), 1);
  	XMoveResizeWindow(dpy, c->win, c->x + 2 * sw, c->y, c->w, c->h); /* some windows require this */
  	setclientstate(c, NormalState);
  	if (c->mon == selmon)
  		unfocus(selmon->sel, 0);
  	c->mon->sel = c;
  	arrange(c->mon);
  	XMapWindow(dpy, c->win);
  	focus(NULL);
  }
  
  void
  mappingnotify(XEvent *e)
  {
  	XMappingEvent *ev = &e->xmapping;
  
  	XRefreshKeyboardMapping(ev);
  	if (ev->request == MappingKeyboard)
  		grabkeys();
  }
  
  void
  maprequest(XEvent *e)
  {
  	static XWindowAttributes wa;
  	XMapRequestEvent *ev = &e->xmaprequest;
  	Client *i;
  	if ((i = wintosystrayicon(ev->window))) {
  		sendevent(i->win, netatom[Xembed], StructureNotifyMask, CurrentTime, XEMBED_WINDOW_ACTIVATE, 0, systray->win, XEMBED_EMBEDDED_VERSION);
  		resizebarwin(selmon);
  		updatesystray();
  	}
  
  	if (!XGetWindowAttributes(dpy, ev->window, &wa))
  		return;
  	if (wa.override_redirect)
  		return;
  	if (!wintoclient(ev->window))
  		manage(ev->window, &wa);
  }
  
  void
  monocle(Monitor *m)
  {
  	unsigned int n = 0;
  	Client *c;
  
  	for (c = m->clients; c; c = c->next)
  		if (ISVISIBLE(c))
  			n++;
  	if (n > 0) /* override layout symbol */
  		snprintf(m->ltsymbol, sizeof m->ltsymbol, "[%d]", n);
  	for (c = nexttiled(m->clients); c; c = nexttiled(c->next))
  		resize(c, m->wx, m->wy, m->ww - 2 * c->bw, m->wh - 2 * c->bw, 0);
  }
  
  void
  motionnotify(XEvent *e)
  {
  	static Monitor *mon = NULL;
  	Monitor *m;
  	XMotionEvent *ev = &e->xmotion;
  
  	if (ev->window != root)
  		return;
  	if ((m = recttomon(ev->x_root, ev->y_root, 1, 1)) != mon && mon) {
  		unfocus(selmon->sel, 1);
  		selmon = m;
  		focus(NULL);
  	}
  	mon = m;
  }
  
  void
  movemouse(const Arg *arg)
  {
  	int x, y, ocx, ocy, nx, ny;
  	Client *c;
  	Monitor *m;
  	XEvent ev;
  	Time lasttime = 0;
  
  	if (!(c = selmon->sel))
  		return;
  	if (c->isfullscreen) /* no support moving fullscreen windows by mouse */
  		return;
  	restack(selmon);
  	ocx = c->x;
  	ocy = c->y;
  	if (XGrabPointer(dpy, root, False, MOUSEMASK, GrabModeAsync, GrabModeAsync,
  		None, cursor[CurMove]->cursor, CurrentTime) != GrabSuccess)
  		return;
  	if (!getrootptr(&x, &y))
  		return;
  	do {
  		XMaskEvent(dpy, MOUSEMASK|ExposureMask|SubstructureRedirectMask, &ev);
  		switch(ev.type) {
  		case ConfigureRequest:
  		case Expose:
  		case MapRequest:
  			handler[ev.type](&ev);
  			break;
  		case MotionNotify:
  			if ((ev.xmotion.time - lasttime) <= (1000 / 60))
  				continue;
  			lasttime = ev.xmotion.time;
  
  			nx = ocx + (ev.xmotion.x - x);
  			ny = ocy + (ev.xmotion.y - y);
  			if (abs(selmon->wx - nx) < snap)
  				nx = selmon->wx;
  			else if (abs((selmon->wx + selmon->ww) - (nx + WIDTH(c))) < snap)
  				nx = selmon->wx + selmon->ww - WIDTH(c);
  			if (abs(selmon->wy - ny) < snap)
  				ny = selmon->wy;
  			else if (abs((selmon->wy + selmon->wh) - (ny + HEIGHT(c))) < snap)
  				ny = selmon->wy + selmon->wh - HEIGHT(c);
  			if (!c->isfloating && selmon->lt[selmon->sellt]->arrange
  			&& (abs(nx - c->x) > snap || abs(ny - c->y) > snap))
  				togglefloating(NULL);
  			if (!selmon->lt[selmon->sellt]->arrange || c->isfloating)
  				resize(c, nx, ny, c->w, c->h, 1);
  			break;
  		}
  	} while (ev.type != ButtonRelease);
  	XUngrabPointer(dpy, CurrentTime);
  	if ((m = recttomon(c->x, c->y, c->w, c->h)) != selmon) {
  		sendmon(c, m);
  		selmon = m;
  		focus(NULL);
  	}
  }
  
  Client *
  nexttiled(Client *c)
  {
  	for (; c && (c->isfloating || !ISVISIBLE(c)); c = c->next);
  	return c;
  }
  
  void
  pop(Client *c)
  {
  	detach(c);
  	attach(c);
  	focus(c);
  	arrange(c->mon);
  }
  
  void
  propertynotify(XEvent *e)
  {
  	Client *c;
  	Window trans;
  	XPropertyEvent *ev = &e->xproperty;
  
  	if ((c = wintosystrayicon(ev->window))) {
  		if (ev->atom == XA_WM_NORMAL_HINTS) {
  			updatesizehints(c);
  			updatesystrayicongeom(c, c->w, c->h);
  		}
  		else
  			updatesystrayiconstate(c, ev);
  		resizebarwin(selmon);
  		updatesystray();
  	}
  	if ((ev->window == root) && (ev->atom == XA_WM_NAME))
  		updatestatus();
  	else if (ev->state == PropertyDelete)
  		return; /* ignore */
  	else if ((c = wintoclient(ev->window))) {
  		switch(ev->atom) {
  		default: break;
  		case XA_WM_TRANSIENT_FOR:
  			if (!c->isfloating && (XGetTransientForHint(dpy, c->win, &trans)) &&
  				(c->isfloating = (wintoclient(trans)) != NULL))
  				arrange(c->mon);
  			break;
  		case XA_WM_NORMAL_HINTS:
  			updatesizehints(c);
  			break;
  		case XA_WM_HINTS:
  			updatewmhints(c);
  			drawbars();
  			break;
  		}
  		if (ev->atom == XA_WM_NAME || ev->atom == netatom[NetWMName]) {
  			updatetitle(c);
  			if (c == c->mon->sel)
  				drawbar(c->mon);
  		}
  		if (ev->atom == netatom[NetWMWindowType])
  			updatewindowtype(c);
  	}
  }
  
  void
  quit(const Arg *arg)
  {
  	running = 0;
  }
  
  Monitor *
  recttomon(int x, int y, int w, int h)
  {
  	Monitor *m, *r = selmon;
  	int a, area = 0;
  
  	for (m = mons; m; m = m->next)
  		if ((a = INTERSECT(x, y, w, h, m)) > area) {
  			area = a;
  			r = m;
  		}
  	return r;
  }
  
  void
  removesystrayicon(Client *i)
  {
  	Client **ii;
  
  	if (!showsystray || !i)
  		return;
  	for (ii = &systray->icons; *ii && *ii != i; ii = &(*ii)->next);
  	if (ii)
  		*ii = i->next;
  	free(i);
  }
  
  
  void
  resize(Client *c, int x, int y, int w, int h, int interact)
  {
  	if (applysizehints(c, &x, &y, &w, &h, interact))
  		resizeclient(c, x, y, w, h);
  }
  
  void
  resizebarwin(Monitor *m) {
  	unsigned int w = m->ww;
  	if (showsystray && m == systraytomon(m) && !systrayonleft)
  		w -= getsystraywidth();
  	XMoveResizeWindow(dpy, m->barwin, m->wx, m->by, w, bh);
  }
  
  void
  resizeclient(Client *c, int x, int y, int w, int h)
  {
  	XWindowChanges wc;
  
  	c->oldx = c->x; c->x = wc.x = x;
  	c->oldy = c->y; c->y = wc.y = y;
  	c->oldw = c->w; c->w = wc.width = w;
  	c->oldh = c->h; c->h = wc.height = h;
  	wc.border_width = c->bw;
  	XConfigureWindow(dpy, c->win, CWX|CWY|CWWidth|CWHeight|CWBorderWidth, &wc);
  	configure(c);
  	XSync(dpy, False);
  }
  
  void
  resizemouse(const Arg *arg)
  {
  	int ocx, ocy, nw, nh;
  	Client *c;
  	Monitor *m;
  	XEvent ev;
  	Time lasttime = 0;
  
  	if (!(c = selmon->sel))
  		return;
  	if (c->isfullscreen) /* no support resizing fullscreen windows by mouse */
  		return;
  	restack(selmon);
  	ocx = c->x;
  	ocy = c->y;
  	if (XGrabPointer(dpy, root, False, MOUSEMASK, GrabModeAsync, GrabModeAsync,
  		None, cursor[CurResize]->cursor, CurrentTime) != GrabSuccess)
  		return;
  	XWarpPointer(dpy, None, c->win, 0, 0, 0, 0, c->w + c->bw - 1, c->h + c->bw - 1);
  	do {
  		XMaskEvent(dpy, MOUSEMASK|ExposureMask|SubstructureRedirectMask, &ev);
  		switch(ev.type) {
  		case ConfigureRequest:
  		case Expose:
  		case MapRequest:
  			handler[ev.type](&ev);
  			break;
  		case MotionNotify:
  			if ((ev.xmotion.time - lasttime) <= (1000 / 60))
  				continue;
  			lasttime = ev.xmotion.time;
  
  			nw = MAX(ev.xmotion.x - ocx - 2 * c->bw + 1, 1);
  			nh = MAX(ev.xmotion.y - ocy - 2 * c->bw + 1, 1);
  			if (c->mon->wx + nw >= selmon->wx && c->mon->wx + nw <= selmon->wx + selmon->ww
  			&& c->mon->wy + nh >= selmon->wy && c->mon->wy + nh <= selmon->wy + selmon->wh)
  			{
  				if (!c->isfloating && selmon->lt[selmon->sellt]->arrange
  				&& (abs(nw - c->w) > snap || abs(nh - c->h) > snap))
  					togglefloating(NULL);
  			}
  			if (!selmon->lt[selmon->sellt]->arrange || c->isfloating)
  				resize(c, c->x, c->y, nw, nh, 1);
  			break;
  		}
  	} while (ev.type != ButtonRelease);
  	XWarpPointer(dpy, None, c->win, 0, 0, 0, 0, c->w + c->bw - 1, c->h + c->bw - 1);
  	XUngrabPointer(dpy, CurrentTime);
  	while (XCheckMaskEvent(dpy, EnterWindowMask, &ev));
  	if ((m = recttomon(c->x, c->y, c->w, c->h)) != selmon) {
  		sendmon(c, m);
  		selmon = m;
  		focus(NULL);
  	}
  }
  
  void
  resizerequest(XEvent *e)
  {
  	XResizeRequestEvent *ev = &e->xresizerequest;
  	Client *i;
  
  	if ((i = wintosystrayicon(ev->window))) {
  		updatesystrayicongeom(i, ev->width, ev->height);
  		resizebarwin(selmon);
  		updatesystray();
  	}
  }
  
  void
  restack(Monitor *m)
  {
  	Client *c;
  	XEvent ev;
  	XWindowChanges wc;
  
  	drawbar(m);
  	if (!m->sel)
  		return;
  	if (m->sel->isfloating || !m->lt[m->sellt]->arrange)
  		XRaiseWindow(dpy, m->sel->win);
  	if (m->lt[m->sellt]->arrange) {
  		wc.stack_mode = Below;
  		wc.sibling = m->barwin;
  		for (c = m->stack; c; c = c->snext)
  			if (!c->isfloating && ISVISIBLE(c)) {
  				XConfigureWindow(dpy, c->win, CWSibling|CWStackMode, &wc);
  				wc.sibling = c->win;
  			}
  	}
  	XSync(dpy, False);
  	while (XCheckMaskEvent(dpy, EnterWindowMask, &ev));
  }
  
  void
  run(void)
  {
  	XEvent ev;
  	/* main event loop */
  	XSync(dpy, False);
  	while (running && !XNextEvent(dpy, &ev))
  		if (handler[ev.type])
  			handler[ev.type](&ev); /* call handler */
  }
  
  void
  scan(void)
  {
  	unsigned int i, num;
  	Window d1, d2, *wins = NULL;
  	XWindowAttributes wa;
  
  	if (XQueryTree(dpy, root, &d1, &d2, &wins, &num)) {
  		for (i = 0; i < num; i++) {
  			if (!XGetWindowAttributes(dpy, wins[i], &wa)
  			|| wa.override_redirect || XGetTransientForHint(dpy, wins[i], &d1))
  				continue;
  			if (wa.map_state == IsViewable || getstate(wins[i]) == IconicState)
  				manage(wins[i], &wa);
  		}
  		for (i = 0; i < num; i++) { /* now the transients */
  			if (!XGetWindowAttributes(dpy, wins[i], &wa))
  				continue;
  			if (XGetTransientForHint(dpy, wins[i], &d1)
  			&& (wa.map_state == IsViewable || getstate(wins[i]) == IconicState))
  				manage(wins[i], &wa);
  		}
  		if (wins)
  			XFree(wins);
  	}
  }
  
  void
  sendmon(Client *c, Monitor *m)
  {
  	if (c->mon == m)
  		return;
  	unfocus(c, 1);
  	detach(c);
  	detachstack(c);
  	c->mon = m;
  	c->tags = m->tagset[m->seltags]; /* assign tags of target monitor */
  	attach(c);
  	attachstack(c);
  	focus(NULL);
  	arrange(NULL);
  }
  
  void
  setclientstate(Client *c, long state)
  {
  	long data[] = { state, None };
  
  	XChangeProperty(dpy, c->win, wmatom[WMState], wmatom[WMState], 32,
  		PropModeReplace, (unsigned char *)data, 2);
  }
  
  int
  sendevent(Window w, Atom proto, int mask, long d0, long d1, long d2, long d3, long d4)
  {
  	int n;
  	Atom *protocols, mt;
  	int exists = 0;
  	XEvent ev;
  
  	if (proto == wmatom[WMTakeFocus] || proto == wmatom[WMDelete]) {
  		mt = wmatom[WMProtocols];
  		if (XGetWMProtocols(dpy, w, &protocols, &n)) {
  			while (!exists && n--)
  				exists = protocols[n] == proto;
  			XFree(protocols);
  		}
  	}
  	else {
  		exists = True;
  		mt = proto;
  	}
  	if (exists) {
  		ev.type = ClientMessage;
  		ev.xclient.window = w;
  		ev.xclient.message_type = mt;
  		ev.xclient.format = 32;
  		ev.xclient.data.l[0] = d0;
  		ev.xclient.data.l[1] = d1;
  		ev.xclient.data.l[2] = d2;
  		ev.xclient.data.l[3] = d3;
  		ev.xclient.data.l[4] = d4;
  		XSendEvent(dpy, w, False, mask, &ev);
  	}
  	return exists;
  }
  
  void
  setfocus(Client *c)
  {
  	if (!c->neverfocus) {
  		XSetInputFocus(dpy, c->win, RevertToPointerRoot, CurrentTime);
  		XChangeProperty(dpy, root, netatom[NetActiveWindow],
  			XA_WINDOW, 32, PropModeReplace,
  			(unsigned char *) &(c->win), 1);
  	}
  	sendevent(c->win, wmatom[WMTakeFocus], NoEventMask, wmatom[WMTakeFocus], CurrentTime, 0, 0, 0);
  }
  
  void
  setfullscreen(Client *c, int fullscreen)
  {
  	if (fullscreen && !c->isfullscreen) {
  		XChangeProperty(dpy, c->win, netatom[NetWMState], XA_ATOM, 32,
  			PropModeReplace, (unsigned char*)&netatom[NetWMFullscreen], 1);
  		c->isfullscreen = 1;
  		c->oldstate = c->isfloating;
  		c->oldbw = c->bw;
  		c->bw = 0;
  		c->isfloating = 1;
  		resizeclient(c, c->mon->mx, c->mon->my, c->mon->mw, c->mon->mh);
  		XRaiseWindow(dpy, c->win);
  	} else if (!fullscreen && c->isfullscreen){
  		XChangeProperty(dpy, c->win, netatom[NetWMState], XA_ATOM, 32,
  			PropModeReplace, (unsigned char*)0, 0);
  		c->isfullscreen = 0;
  		c->isfloating = c->oldstate;
  		c->bw = c->oldbw;
  		c->x = c->oldx;
  		c->y = c->oldy;
  		c->w = c->oldw;
  		c->h = c->oldh;
  		resizeclient(c, c->x, c->y, c->w, c->h);
  		arrange(c->mon);
  	}
  }
  
  void
  setlayout(const Arg *arg)
  {
  	if (!arg || !arg->v || arg->v != selmon->lt[selmon->sellt])
  		selmon->sellt ^= 1;
  	if (arg && arg->v)
  		selmon->lt[selmon->sellt] = (Layout *)arg->v;
  	strncpy(selmon->ltsymbol, selmon->lt[selmon->sellt]->symbol, sizeof selmon->ltsymbol);
  	if (selmon->sel)
  		arrange(selmon);
  	else
  		drawbar(selmon);
  }
  
  void
  setcfact(const Arg *arg) {
  	float f;
  	Client *c;
  
  	c = selmon->sel;
  
  	if(!arg || !c || !selmon->lt[selmon->sellt]->arrange)
  		return;
  	f = arg->f + c->cfact;
  	if(arg->f == 0.0)
  		f = 1.0;
  	else if(f < 0.25 || f > 4.0)
  		return;
  	c->cfact = f;
  	arrange(selmon);
  }
  
  /* arg > 1.0 will set mfact absolutely */
  void
  setmfact(const Arg *arg)
  {
  	float f;
  
  	if (!arg || !selmon->lt[selmon->sellt]->arrange)
  		return;
  	f = arg->f < 1.0 ? arg->f + selmon->mfact : arg->f - 1.0;
  	if (f < 0.1 || f > 0.9)
  		return;
  	selmon->mfact = f;
  	arrange(selmon);
  }
  
  void
  setup(void)
  {
  	int i;
  	XSetWindowAttributes wa;
  	Atom utf8string;
  
  	/* clean up any zombies immediately */
  	sigchld(0);
  
  	/* init screen */
  	screen = DefaultScreen(dpy);
  	sw = DisplayWidth(dpy, screen);
  	sh = DisplayHeight(dpy, screen);
  	root = RootWindow(dpy, screen);
  	drw = drw_create(dpy, screen, root, sw, sh);
  	if (!drw_font_create(drw, font))
  		die("no fonts could be loaded.");
  	lrpad = drw->font->h;
  	bh = drw->font->h + 2;
  	updategeom();
  	/* init atoms */
  	utf8string = XInternAtom(dpy, "UTF8_STRING", False);
  	wmatom[WMProtocols] = XInternAtom(dpy, "WM_PROTOCOLS", False);
  	wmatom[WMDelete] = XInternAtom(dpy, "WM_DELETE_WINDOW", False);
  	wmatom[WMState] = XInternAtom(dpy, "WM_STATE", False);
  	wmatom[WMTakeFocus] = XInternAtom(dpy, "WM_TAKE_FOCUS", False);
  	netatom[NetActiveWindow] = XInternAtom(dpy, "_NET_ACTIVE_WINDOW", False);
  	netatom[NetSupported] = XInternAtom(dpy, "_NET_SUPPORTED", False);
  	netatom[NetSystemTray] = XInternAtom(dpy, "_NET_SYSTEM_TRAY_S0", False);
  	netatom[NetSystemTrayOP] = XInternAtom(dpy, "_NET_SYSTEM_TRAY_OPCODE", False);
  	netatom[NetSystemTrayOrientation] = XInternAtom(dpy, "_NET_SYSTEM_TRAY_ORIENTATION", False);
  	netatom[NetSystemTrayOrientationHorz] = XInternAtom(dpy, "_NET_SYSTEM_TRAY_ORIENTATION_HORZ", False);
  	netatom[NetWMName] = XInternAtom(dpy, "_NET_WM_NAME", False);
  	netatom[NetWMState] = XInternAtom(dpy, "_NET_WM_STATE", False);
  	netatom[NetWMCheck] = XInternAtom(dpy, "_NET_SUPPORTING_WM_CHECK", False);
  	netatom[NetWMFullscreen] = XInternAtom(dpy, "_NET_WM_STATE_FULLSCREEN", False);
  	netatom[NetWMWindowType] = XInternAtom(dpy, "_NET_WM_WINDOW_TYPE", False);
  	netatom[NetWMWindowTypeDialog] = XInternAtom(dpy, "_NET_WM_WINDOW_TYPE_DIALOG", False);
  	netatom[NetClientList] = XInternAtom(dpy, "_NET_CLIENT_LIST", False);
  	xatom[Manager] = XInternAtom(dpy, "MANAGER", False);
  	xatom[Xembed] = XInternAtom(dpy, "_XEMBED", False);
  	xatom[XembedInfo] = XInternAtom(dpy, "_XEMBED_INFO", False);
  	/* init cursors */
  	cursor[CurNormal] = drw_cur_create(drw, XC_left_ptr);
  	cursor[CurResize] = drw_cur_create(drw, XC_sizing);
  	cursor[CurMove] = drw_cur_create(drw, XC_fleur);
  	/* init appearance */
  	scheme = ecalloc(LENGTH(colors), sizeof(Clr *));
  	for (i = 0; i < LENGTH(colors); i++)
  		scheme[i] = drw_scm_create(drw, colors[i], 3);
  	/* init system tray */
  	updatesystray();
  	/* init bars */
  	updatebars();
  	updatestatus();
  	/* supporting window for NetWMCheck */
  	wmcheckwin = XCreateSimpleWindow(dpy, root, 0, 0, 1, 1, 0, 0, 0);
  	XChangeProperty(dpy, wmcheckwin, netatom[NetWMCheck], XA_WINDOW, 32,
  		PropModeReplace, (unsigned char *) &wmcheckwin, 1);
  	XChangeProperty(dpy, wmcheckwin, netatom[NetWMName], utf8string, 8,
  		PropModeReplace, (unsigned char *) "dwm", 3);
  	XChangeProperty(dpy, root, netatom[NetWMCheck], XA_WINDOW, 32,
  		PropModeReplace, (unsigned char *) &wmcheckwin, 1);
  	/* EWMH support per view */
  	XChangeProperty(dpy, root, netatom[NetSupported], XA_ATOM, 32,
  		PropModeReplace, (unsigned char *) netatom, NetLast);
  	XDeleteProperty(dpy, root, netatom[NetClientList]);
  	/* select events */
  	wa.cursor = cursor[CurNormal]->cursor;
  	wa.event_mask = SubstructureRedirectMask|SubstructureNotifyMask
  		|ButtonPressMask|PointerMotionMask|EnterWindowMask
  		|LeaveWindowMask|StructureNotifyMask|PropertyChangeMask;
  	XChangeWindowAttributes(dpy, root, CWEventMask|CWCursor, &wa);
  	XSelectInput(dpy, root, wa.event_mask);
  	grabkeys();
  	focus(NULL);
  }
  
  void
  seturgent(Client *c, int urg)
  {
  	XWMHints *wmh;
  
  	c->isurgent = urg;
  	if (!(wmh = XGetWMHints(dpy, c->win)))
  		return;
  	wmh->flags = urg ? (wmh->flags | XUrgencyHint) : (wmh->flags & ~XUrgencyHint);
  	XSetWMHints(dpy, c->win, wmh);
  	XFree(wmh);
  }
  
  void
  showhide(Client *c)
  {
  	if (!c)
  		return;
  	if (ISVISIBLE(c)) {
  		/* show clients top down */
  		XMoveWindow(dpy, c->win, c->x, c->y);
  		if ((!c->mon->lt[c->mon->sellt]->arrange || c->isfloating) && !c->isfullscreen)
  			resize(c, c->x, c->y, c->w, c->h, 0);
  		showhide(c->snext);
  	} else {
  		/* hide clients bottom up */
  		showhide(c->snext);
  		XMoveWindow(dpy, c->win, WIDTH(c) * -2, c->y);
  	}
  }
  
  void
  sigchld(int unused)
  {
  	if (signal(SIGCHLD, sigchld) == SIG_ERR)
  		die("can't install SIGCHLD handler:");
  	while (0 < waitpid(-1, NULL, WNOHANG));
  }
  
  void
  spawn(const Arg *arg)
  {
  	if (arg->v == dmenucmd)
  		dmenumon[0] = '0' + selmon->num;
  	if (fork() == 0) {
  		if (dpy)
  			close(ConnectionNumber(dpy));
  		setsid();
  		execvp(((char **)arg->v)[0], (char **)arg->v);
  		fprintf(stderr, "dwm: execvp %s", ((char **)arg->v)[0]);
  		perror(" failed");
  		exit(EXIT_SUCCESS);
  	}
  }
  
  void
  tag(const Arg *arg)
  {
  	if (selmon->sel && arg->ui & TAGMASK) {
  		selmon->sel->tags = arg->ui & TAGMASK;
  		focus(NULL);
  		arrange(selmon);
  	}
  }
  
  void
  tagmon(const Arg *arg)
  {
  	if (!selmon->sel || !mons->next)
  		return;
  	sendmon(selmon->sel, dirtomon(arg->i));
  }
  
  void
  togglebar(const Arg *arg)
  {
  	selmon->showbar = !selmon->showbar;
  	updatebarpos(selmon);
  	resizebarwin(selmon);
  	if (showsystray) {
  		XWindowChanges wc;
  		if (!selmon->showbar)
  			wc.y = -bh;
  		else if (selmon->showbar) {
  			wc.y = 0;
  			if (!selmon->topbar)
  				wc.y = selmon->mh - bh;
  		}
  		XConfigureWindow(dpy, systray->win, CWY, &wc);
  	}
  	arrange(selmon);
  }
  
  void
  togglefloating(const Arg *arg)
  {
  	if (!selmon->sel)
  		return;
  	if (selmon->sel->isfullscreen) /* no support for fullscreen windows */
  		return;
  	selmon->sel->isfloating = !selmon->sel->isfloating || selmon->sel->isfixed;
  	if (selmon->sel->isfloating)
  		resize(selmon->sel, selmon->sel->x, selmon->sel->y,
  			selmon->sel->w, selmon->sel->h, 0);
  	arrange(selmon);
  }
  
  void
  toggletag(const Arg *arg)
  {
  	unsigned int newtags;
  
  	if (!selmon->sel)
  		return;
  	newtags = selmon->sel->tags ^ (arg->ui & TAGMASK);
  	if (newtags) {
  		selmon->sel->tags = newtags;
  		focus(NULL);
  		arrange(selmon);
  	}
  }
  
  void
  toggleview(const Arg *arg)
  {
  	unsigned int newtagset = selmon->tagset[selmon->seltags] ^ (arg->ui & TAGMASK);
  
  	if (newtagset) {
  		selmon->tagset[selmon->seltags] = newtagset;
  		focus(NULL);
  		arrange(selmon);
  	}
  }
  
  void
  unfocus(Client *c, int setfocus)
  {
  	if (!c)
  		return;
  	grabbuttons(c, 0);
  	XSetWindowBorder(dpy, c->win, scheme[SchemeNorm][ColBorder].pixel);
  	if (setfocus) {
  		XSetInputFocus(dpy, root, RevertToPointerRoot, CurrentTime);
  		XDeleteProperty(dpy, root, netatom[NetActiveWindow]);
  	}
  }
  
  void
  unmanage(Client *c, int destroyed)
  {
  	Monitor *m = c->mon;
  	XWindowChanges wc;
  
  	detach(c);
  	detachstack(c);
  	if (!destroyed) {
  		wc.border_width = c->oldbw;
  		XGrabServer(dpy); /* avoid race conditions */
  		XSetErrorHandler(xerrordummy);
  		XConfigureWindow(dpy, c->win, CWBorderWidth, &wc); /* restore border */
  		XUngrabButton(dpy, AnyButton, AnyModifier, c->win);
  		setclientstate(c, WithdrawnState);
  		XSync(dpy, False);
  		XSetErrorHandler(xerror);
  		XUngrabServer(dpy);
  	}
  	free(c);
  	focus(NULL);
  	updateclientlist();
  	arrange(m);
  }
  
  void
  unmapnotify(XEvent *e)
  {
  	Client *c;
  	XUnmapEvent *ev = &e->xunmap;
  
  	if ((c = wintoclient(ev->window))) {
  		if (ev->send_event)
  			setclientstate(c, WithdrawnState);
  		else
  			unmanage(c, 0);
  	}
  	else if ((c = wintosystrayicon(ev->window))) {
  		/* KLUDGE! sometimes icons occasionally unmap their windows, but do
  		 * _not_ destroy them. We map those windows back */
  		XMapRaised(dpy, c->win);
  		updatesystray();
  	}
  }
  
  void
  updatebars(void)
  {
  	unsigned int w;
  	Monitor *m;
  	XSetWindowAttributes wa = {
  		.override_redirect = True,
  		.background_pixmap = ParentRelative,
  		.event_mask = ButtonPressMask|ExposureMask
  	};
  	XClassHint ch = {"dwm", "dwm"};
  	for (m = mons; m; m = m->next) {
  		if (m->barwin)
  			continue;
  		w = m->ww;
  		if (showsystray && m == systraytomon(m))
  			w -= getsystraywidth();
  		m->barwin = XCreateWindow(dpy, root, m->wx, m->by, w, bh, 0, DefaultDepth(dpy, screen),
  				CopyFromParent, DefaultVisual(dpy, screen),
  				CWOverrideRedirect|CWBackPixmap|CWEventMask, &wa);
  		XDefineCursor(dpy, m->barwin, cursor[CurNormal]->cursor);
  		if (showsystray && m == systraytomon(m))
  			XMapRaised(dpy, systray->win);
  		XMapRaised(dpy, m->barwin);
  		XSetClassHint(dpy, m->barwin, &ch);
  	}
  }
  
  void
  updatebarpos(Monitor *m)
  {
  	m->wy = m->my;
  	m->wh = m->mh;
  	if (m->showbar) {
  		m->wh -= bh;
  		m->by = m->topbar ? m->wy : m->wy + m->wh;
  		m->wy = m->topbar ? m->wy + bh : m->wy;
  	} else
  		m->by = -bh;
  }
  
  void
  updateclientlist()
  {
  	Client *c;
  	Monitor *m;
  
  	XDeleteProperty(dpy, root, netatom[NetClientList]);
  	for (m = mons; m; m = m->next)
  		for (c = m->clients; c; c = c->next)
  			XChangeProperty(dpy, root, netatom[NetClientList],
  				XA_WINDOW, 32, PropModeAppend,
  				(unsigned char *) &(c->win), 1);
  }
  
  int
  updategeom(void)
  {
  	int dirty = 0;
  
  #ifdef XINERAMA
  	if (XineramaIsActive(dpy)) {
  		int i, j, n, nn;
  		Client *c;
  		Monitor *m;
  		XineramaScreenInfo *info = XineramaQueryScreens(dpy, &nn);
  		XineramaScreenInfo *unique = NULL;
  
  		for (n = 0, m = mons; m; m = m->next, n++);
  		/* only consider unique geometries as separate screens */
  		unique = ecalloc(nn, sizeof(XineramaScreenInfo));
  		for (i = 0, j = 0; i < nn; i++)
  			if (isuniquegeom(unique, j, &info[i]))
  				memcpy(&unique[j++], &info[i], sizeof(XineramaScreenInfo));
  		XFree(info);
  		nn = j;
  		if (n <= nn) { /* new monitors available */
  			for (i = 0; i < (nn - n); i++) {
  				for (m = mons; m && m->next; m = m->next);
  				if (m)
  					m->next = createmon();
  				else
  					mons = createmon();
  			}
  			for (i = 0, m = mons; i < nn && m; m = m->next, i++)
  				if (i >= n
  				|| unique[i].x_org != m->mx || unique[i].y_org != m->my
  				|| unique[i].width != m->mw || unique[i].height != m->mh)
  				{
  					dirty = 1;
  					m->num = i;
  					m->mx = m->wx = unique[i].x_org;
  					m->my = m->wy = unique[i].y_org;
  					m->mw = m->ww = unique[i].width;
  					m->mh = m->wh = unique[i].height;
  					updatebarpos(m);
  				}
  		} else { /* less monitors available nn < n */
  			for (i = nn; i < n; i++) {
  				for (m = mons; m && m->next; m = m->next);
  				while ((c = m->clients)) {
  					dirty = 1;
  					m->clients = c->next;
  					detachstack(c);
  					c->mon = mons;
  					attach(c);
  					attachstack(c);
  				}
  				if (m == selmon)
  					selmon = mons;
  				cleanupmon(m);
  			}
  		}
  		free(unique);
  	} else
  #endif /* XINERAMA */
  	{ /* default monitor setup */
  		if (!mons)
  			mons = createmon();
  		if (mons->mw != sw || mons->mh != sh) {
  			dirty = 1;
  			mons->mw = mons->ww = sw;
  			mons->mh = mons->wh = sh;
  			updatebarpos(mons);
  		}
  	}
  	if (dirty) {
  		selmon = mons;
  		selmon = wintomon(root);
  	}
  	return dirty;
  }
  
  void
  updatenumlockmask(void)
  {
  	unsigned int i, j;
  	XModifierKeymap *modmap;
  
  	numlockmask = 0;
  	modmap = XGetModifierMapping(dpy);
  	for (i = 0; i < 8; i++)
  		for (j = 0; j < modmap->max_keypermod; j++)
  			if (modmap->modifiermap[i * modmap->max_keypermod + j]
  				== XKeysymToKeycode(dpy, XK_Num_Lock))
  				numlockmask = (1 << i);
  	XFreeModifiermap(modmap);
  }
  
  void
  updatesizehints(Client *c)
  {
  	long msize;
  	XSizeHints size;
  
  	if (!XGetWMNormalHints(dpy, c->win, &size, &msize))
  		/* size is uninitialized, ensure that size.flags aren't used */
  		size.flags = PSize;
  	if (size.flags & PBaseSize) {
  		c->basew = size.base_width;
  		c->baseh = size.base_height;
  	} else if (size.flags & PMinSize) {
  		c->basew = size.min_width;
  		c->baseh = size.min_height;
  	} else
  		c->basew = c->baseh = 0;
  	if (size.flags & PResizeInc) {
  		c->incw = size.width_inc;
  		c->inch = size.height_inc;
  	} else
  		c->incw = c->inch = 0;
  	if (size.flags & PMaxSize) {
  		c->maxw = size.max_width;
  		c->maxh = size.max_height;
  	} else
  		c->maxw = c->maxh = 0;
  	if (size.flags & PMinSize) {
  		c->minw = size.min_width;
  		c->minh = size.min_height;
  	} else if (size.flags & PBaseSize) {
  		c->minw = size.base_width;
  		c->minh = size.base_height;
  	} else
  		c->minw = c->minh = 0;
  	if (size.flags & PAspect) {
  		c->mina = (float)size.min_aspect.y / size.min_aspect.x;
  		c->maxa = (float)size.max_aspect.x / size.max_aspect.y;
  	} else
  		c->maxa = c->mina = 0.0;
  	c->isfixed = (c->maxw && c->maxh && c->maxw == c->minw && c->maxh == c->minh);
  }
  
  void
  updatestatus(void)
  {
  	if (!gettextprop(root, XA_WM_NAME, stext, sizeof(stext)))
  		strcpy(stext, "dwm-"VERSION);
  	drawbar(selmon);
  	updatesystray();
  }
  
  void
  updatesystrayicongeom(Client *i, int w, int h)
  {
  	if (i) {
  		i->h = bh;
  		if (w == h)
  			i->w = bh;
  		else if (h == bh)
  			i->w = w;
  		else
  			i->w = (int) ((float)bh * ((float)w / (float)h));
  		applysizehints(i, &(i->x), &(i->y), &(i->w), &(i->h), False);
  		/* force icons into the systray dimensions if they don't want to */
  		if (i->h > bh) {
  			if (i->w == i->h)
  				i->w = bh;
  			else
  				i->w = (int) ((float)bh * ((float)i->w / (float)i->h));
  			i->h = bh;
  		}
  	}
  }
  
  void
  updatesystrayiconstate(Client *i, XPropertyEvent *ev)
  {
  	long flags;
  	int code = 0;
  
  	if (!showsystray || !i || ev->atom != xatom[XembedInfo] ||
  			!(flags = getatomprop(i, xatom[XembedInfo])))
  		return;
  
  	if (flags & XEMBED_MAPPED && !i->tags) {
  		i->tags = 1;
  		code = XEMBED_WINDOW_ACTIVATE;
  		XMapRaised(dpy, i->win);
  		setclientstate(i, NormalState);
  	}
  	else if (!(flags & XEMBED_MAPPED) && i->tags) {
  		i->tags = 0;
  		code = XEMBED_WINDOW_DEACTIVATE;
  		XUnmapWindow(dpy, i->win);
  		setclientstate(i, WithdrawnState);
  	}
  	else
  		return;
  	sendevent(i->win, xatom[Xembed], StructureNotifyMask, CurrentTime, code, 0,
  			systray->win, XEMBED_EMBEDDED_VERSION);
  }
  
  void
  updatesystray(void)
  {
  	XSetWindowAttributes wa;
  	XWindowChanges wc;
  	Client *i;
  	Monitor *m = systraytomon(NULL);
  	unsigned int x = m->mx + m->mw;
  	unsigned int sw = TEXTW(stext) - lrpad + systrayspacing;
  	unsigned int w = 1;
  
  	if (!showsystray)
  		return;
  	if (systrayonleft)
  		x -= sw + lrpad / 2;
  	if (!systray) {
  		/* init systray */
  		if (!(systray = (Systray *)calloc(1, sizeof(Systray))))
  			die("fatal: could not malloc() %u bytes\n", sizeof(Systray));
  		systray->win = XCreateSimpleWindow(dpy, root, x, m->by, w, bh, 0, 0, scheme[SchemeSel][ColBg].pixel);
  		wa.event_mask        = ButtonPressMask | ExposureMask;
  		wa.override_redirect = True;
  		wa.background_pixel  = scheme[SchemeNorm][ColBg].pixel;
  		XSelectInput(dpy, systray->win, SubstructureNotifyMask);
  		XChangeProperty(dpy, systray->win, netatom[NetSystemTrayOrientation], XA_CARDINAL, 32,
  				PropModeReplace, (unsigned char *)&netatom[NetSystemTrayOrientationHorz], 1);
  		XChangeWindowAttributes(dpy, systray->win, CWEventMask|CWOverrideRedirect|CWBackPixel, &wa);
  		XMapRaised(dpy, systray->win);
  		XSetSelectionOwner(dpy, netatom[NetSystemTray], systray->win, CurrentTime);
  		if (XGetSelectionOwner(dpy, netatom[NetSystemTray]) == systray->win) {
  			sendevent(root, xatom[Manager], StructureNotifyMask, CurrentTime, netatom[NetSystemTray], systray->win, 0, 0);
  			XSync(dpy, False);
  		}
  		else {
  			fprintf(stderr, "dwm: unable to obtain system tray.\n");
  			free(systray);
  			systray = NULL;
  			return;
  		}
  	}
  	for (w = 0, i = systray->icons; i; i = i->next) {
  		/* make sure the background color stays the same */
  		wa.background_pixel  = scheme[SchemeNorm][ColBg].pixel;
  		XChangeWindowAttributes(dpy, i->win, CWBackPixel, &wa);
  		XMapRaised(dpy, i->win);
  		w += systrayspacing;
  		i->x = w;
  		XMoveResizeWindow(dpy, i->win, i->x, 0, i->w, i->h);
  		w += i->w;
  		if (i->mon != m)
  			i->mon = m;
  	}
  	w = w ? w + systrayspacing : 1;
  	x -= w;
  	XMoveResizeWindow(dpy, systray->win, x, m->by, w, bh);
  	wc.x = x; wc.y = m->by; wc.width = w; wc.height = bh;
  	wc.stack_mode = Above; wc.sibling = m->barwin;
  	XConfigureWindow(dpy, systray->win, CWX|CWY|CWWidth|CWHeight|CWSibling|CWStackMode, &wc);
  	XMapWindow(dpy, systray->win);
  	XMapSubwindows(dpy, systray->win);
  	/* redraw background */
  	XSetForeground(dpy, drw->gc, scheme[SchemeNorm][ColBg].pixel);
  	XFillRectangle(dpy, systray->win, drw->gc, 0, 0, w, bh);
  	XSync(dpy, False);
  }
  
  void
  updatetitle(Client *c)
  {
  	if (!gettextprop(c->win, netatom[NetWMName], c->name, sizeof c->name))
  		gettextprop(c->win, XA_WM_NAME, c->name, sizeof c->name);
  	if (c->name[0] == '\0') /* hack to mark broken clients */
  		strcpy(c->name, broken);
  }
  
  void
  updatewindowtype(Client *c)
  {
  	Atom state = getatomprop(c, netatom[NetWMState]);
  	Atom wtype = getatomprop(c, netatom[NetWMWindowType]);
  
  	if (state == netatom[NetWMFullscreen])
  		setfullscreen(c, 1);
  	if (wtype == netatom[NetWMWindowTypeDialog])
  		c->isfloating = 1;
  }
  
  void
  updatewmhints(Client *c)
  {
  	XWMHints *wmh;
  
  	if ((wmh = XGetWMHints(dpy, c->win))) {
  		if (c == selmon->sel && wmh->flags & XUrgencyHint) {
  			wmh->flags &= ~XUrgencyHint;
  			XSetWMHints(dpy, c->win, wmh);
  		} else
  			c->isurgent = (wmh->flags & XUrgencyHint) ? 1 : 0;
  		if (wmh->flags & InputHint)
  			c->neverfocus = !wmh->input;
  		else
  			c->neverfocus = 0;
  		XFree(wmh);
  	}
  }
  
  void
  view(const Arg *arg)
  {
  	if ((arg->ui & TAGMASK) == selmon->tagset[selmon->seltags])
  		return;
  	selmon->seltags ^= 1; /* toggle sel tagset */
  	if (arg->ui & TAGMASK)
  		selmon->tagset[selmon->seltags] = arg->ui & TAGMASK;
  	focus(NULL);
  	arrange(selmon);
  }
  
  Client *
  wintoclient(Window w)
  {
  	Client *c;
  	Monitor *m;
  
  	for (m = mons; m; m = m->next)
  		for (c = m->clients; c; c = c->next)
  			if (c->win == w)
  				return c;
  	return NULL;
  }
  
  Client *
  wintosystrayicon(Window w) {
  	Client *i = NULL;
  
  	if (!showsystray || !w)
  		return i;
  	for (i = systray->icons; i && i->win != w; i = i->next) ;
  	return i;
  }
  
  Monitor *
  wintomon(Window w)
  {
  	int x, y;
  	Client *c;
  	Monitor *m;
  
  	if (w == root && getrootptr(&x, &y))
  		return recttomon(x, y, 1, 1);
  	for (m = mons; m; m = m->next)
  		if (w == m->barwin)
  			return m;
  	if ((c = wintoclient(w)))
  		return c->mon;
  	return selmon;
  }
  
  /* There's no way to check accesses to destroyed windows, thus those cases are
   * ignored (especially on UnmapNotify's). Other types of errors call Xlibs
   * default error handler, which may call exit. */
  int
  xerror(Display *dpy, XErrorEvent *ee)
  {
  	if (ee->error_code == BadWindow
  	|| (ee->request_code == X_SetInputFocus && ee->error_code == BadMatch)
  	|| (ee->request_code == X_PolyText8 && ee->error_code == BadDrawable)
  	|| (ee->request_code == X_PolyFillRectangle && ee->error_code == BadDrawable)
  	|| (ee->request_code == X_PolySegment && ee->error_code == BadDrawable)
  	|| (ee->request_code == X_ConfigureWindow && ee->error_code == BadMatch)
  	|| (ee->request_code == X_GrabButton && ee->error_code == BadAccess)
  	|| (ee->request_code == X_GrabKey && ee->error_code == BadAccess)
  	|| (ee->request_code == X_CopyArea && ee->error_code == BadDrawable))
  		return 0;
  	fprintf(stderr, "dwm: fatal error: request code=%d, error code=%d\n",
  		ee->request_code, ee->error_code);
  	return xerrorxlib(dpy, ee); /* may call exit */
  }
  
  int
  xerrordummy(Display *dpy, XErrorEvent *ee)
  {
  	return 0;
  }
  
  /* Startup Error handler to check if another window manager
   * is already running. */
  int
  xerrorstart(Display *dpy, XErrorEvent *ee)
  {
  	die("dwm: another window manager is already running");
  	return -1;
  }
  
  Monitor *
  systraytomon(Monitor *m) {
  	Monitor *t;
  	int i, n;
  	if(!systraypinning) {
  		if(!m)
  			return selmon;
  		return m == selmon ? m : NULL;
  	}
  	for(n = 1, t = mons; t && t->next; n++, t = t->next) ;
  	for(i = 1, t = mons; t && t->next && i < systraypinning; i++, t = t->next) ;
  	if(systraypinningfailfirst && n < systraypinning)
  		return mons;
  	return t;
  }
  
  void
  zoom(const Arg *arg)
  {
  	Client *c = selmon->sel;
  
  	if (!selmon->lt[selmon->sellt]->arrange
  	|| (selmon->sel && selmon->sel->isfloating))
  		return;
  	if (c == nexttiled(selmon->clients))
  		if (!c || !(c = nexttiled(c->next)))
  			return;
  	pop(c);
  }
  
  int
  main(int argc, char *argv[])
  {
  	if (argc == 2 && !strcmp("-v", argv[1]))
  		die("dwm-"VERSION);
  	else if (argc != 1)
  		die("usage: dwm [-v]");
  	if (!setlocale(LC_CTYPE, "") || !XSupportsLocale())
  		fputs("warning: no locale support\n", stderr);
  	if (!(dpy = XOpenDisplay(NULL)))
  		die("dwm: cannot open display");
  	checkotherwm();
  	setup();
  #ifdef __OpenBSD__
  	if (pledge("stdio rpath proc exec", NULL) == -1)
  		die("pledge");
  #endif /* __OpenBSD__ */
  	scan();
  	run();
  	cleanup();
  	XCloseDisplay(dpy);
  	return EXIT_SUCCESS;
  }
  