dwm/dwm.c

/* 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>
#include <X11/Xresource.h>
#ifdef XINERAMA
#include <X11/extensions/Xinerama.h>
#endif /* XINERAMA */
#include <X11/Xft/Xft.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_fontset_getwidth(drw, (X)) + lrpad)

/* enums */
enum { CurNormal, CurResize, CurMove, CurLast }; /* cursor */
enum { SchemeNorm, SchemeSel }; /* color schemes */
enum { NetSupported, NetWMName, NetWMState, NetWMCheck,
       NetWMFullscreen, NetActiveWindow, NetWMWindowType,
       NetWMWindowTypeDialog, NetClientList, NetLast }; /* EWMH 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;
	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, iscentered, 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  */
	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 iscentered;
	int isfloating;
	int monitor;
} Rule;

/* Xresources preferences */
enum resource_type {
	STRING = 0,
	INTEGER = 1,
	FLOAT = 2
};

typedef struct {
	char *name;
	enum resource_type type;
	void *dst;
} ResourcePref;

/* 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 Atom getatomprop(Client *c, Atom prop);
static int getrootptr(int *x, int *y);
static long getstate(Window w);
static int gettextprop(Window w, Atom atom, char *text, unsigned int size);
static void grabbuttons(Client *c, int focused);
static void grabkeys(void);
static void incnmaster(const Arg *arg);
static 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 resize(Client *c, int x, int y, int w, int h, int interact);
static void resizeclient(Client *c, int x, int y, int w, int h);
static void resizemouse(const Arg *arg);
static void restack(Monitor *m);
static void run(void);
static void scan(void);
static int sendevent(Client *c, Atom proto);
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 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 void tag(const Arg *arg);
static void tagmon(const Arg *arg);
static void tile(Monitor *);
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 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 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);
static void load_xresources(void);
static void resource_load(XrmDatabase db, char *name, enum resource_type rtype, void *dst);

/* variables */
static const char broken[] = "broken";
static char stext[256];
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,
	[UnmapNotify] = unmapnotify
};
static Atom wmatom[WMLast], netatom[NetLast];
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->iscentered = 0;
	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->iscentered = r->iscentered;
			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 - (int)TEXTW(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);
	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)
{
	XClientMessageEvent *cme = &e->xclient;
	Client *c = wintoclient(cme->window);

	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;