1/* (C)opyright MMVI-MMVII Anselm R. Garbe <garbeam at gmail dot com>
  2 * See LICENSE file for license details.
  3 *
  4 * dynamic window manager is designed like any other X client as well. It is
  5 * driven through handling X events. In contrast to other X clients, a window
  6 * manager selects for SubstructureRedirectMask on the root window, to receive
  7 * events about window (dis-)appearance.  Only one X connection at a time is
  8 * allowed to select for this event mask.
  9 *
 10 * Calls to fetch an X event from the event queue are blocking.  Due reading
 11 * status text from standard input, a select()-driven main loop has been
 12 * implemented which selects for reads on the X connection and STDIN_FILENO to
 13 * handle all data smoothly. The event handlers of dwm are organized in an
 14 * array which is accessed whenever a new event has been fetched. This allows
 15 * event dispatching in O(1) time.
 16 *
 17 * Each child of the root window is called a client, except windows which have
 18 * set the override_redirect flag.  Clients are organized in a global
 19 * doubly-linked client list, the focus history is remembered through a global
 20 * stack list. Each client contains an array of Bools of the same size as the
 21 * global tags array to indicate the tags of a client.  For each client dwm
 22 * creates a small title window, which is resized whenever the (_NET_)WM_NAME
 23 * properties are updated or the client is moved/resized.
 24 *
 25 * Keys and tagging rules are organized as arrays and defined in the config.h
 26 * file. These arrays are kept static in event.o and tag.o respectively,
 27 * because no other part of dwm needs access to them.  The current mode is
 28 * represented by the arrange() function pointer, which wether points to
 29 * dofloat() or dotile(). 
 30 *
 31 * To understand everything else, start reading main.c:main().
 32 */
 33
 34#include "config.h"
 35#include <X11/Xlib.h>
 36
 37/* mask shorthands, used in event.c and client.c */
 38#define BUTTONMASK		(ButtonPressMask | ButtonReleaseMask)
 39/* other stuff used in different places */
 40#define PROTODELWIN		1
 41
 42enum { NetSupported, NetWMName, NetLast };		/* EWMH atoms */
 43enum { WMProtocols, WMDelete, WMLast };			/* default atoms */
 44enum { CurNormal, CurResize, CurMove, CurLast };	/* cursor */
 45enum { ColBorder, ColFG, ColBG, ColLast };		/* color */
 46
 47typedef union {
 48	const char *cmd;
 49	int i;
 50} Arg; /* argument type */
 51
 52typedef struct {
 53	int ascent;
 54	int descent;
 55	int height;
 56	XFontSet set;
 57	XFontStruct *xfont;
 58} Fnt;
 59
 60typedef struct {
 61	int x, y, w, h;
 62	unsigned long norm[ColLast];
 63	unsigned long sel[ColLast];
 64	Drawable drawable;
 65	Fnt font;
 66	GC gc;
 67} DC; /* draw context */
 68
 69typedef struct Client Client;
 70struct Client {
 71	char name[256];
 72	int proto;
 73	int x, y, w, h;
 74	int rx, ry, rw, rh; /* revert geometry */
 75	int basew, baseh, incw, inch, maxw, maxh, minw, minh;
 76	long flags; 
 77	unsigned int border;
 78	Bool isfloat, isfixed, ismax;
 79	Bool *tags;
 80	Client *next;
 81	Client *prev;
 82	Client *snext;
 83	Window win;
 84};
 85
 86extern const char *tags[];			/* all tags */
 87extern char stext[256];				/* status text */
 88extern int bh, bmw;				/* bar height, bar mode label width */
 89extern int screen, sx, sy, sw, sh;		/* screen geometry */
 90extern int wax, way, wah, waw;			/* windowarea geometry */
 91extern unsigned int master, nmaster;		/* master percent, number of master clients */
 92extern unsigned int ntags, numlockmask;		/* number of tags, dynamic lock mask */
 93extern void (*handler[LASTEvent])(XEvent *);	/* event handler */
 94extern void (*arrange)(void);			/* arrange function, indicates mode  */
 95extern Atom wmatom[WMLast], netatom[NetLast];
 96extern Bool running, selscreen, *seltag;	/* seltag is array of Bool */
 97extern Client *clients, *sel, *stack;		/* global client list and stack */
 98extern Cursor cursor[CurLast];
 99extern DC dc;					/* global draw context */
100extern Display *dpy;
101extern Window root, barwin;
102
103/* client.c */
104extern void configure(Client *c);		/* send synthetic configure event */
105extern void focus(Client *c);			/* focus c, c may be NULL */
106extern Client *getclient(Window w);		/* return client of w */
107extern void killclient(Arg *arg);		/* kill c nicely */
108extern void manage(Window w, XWindowAttributes *wa);	/* manage new client */
109extern void resize(Client *c, Bool sizehints);	/* resize c*/
110extern void updatesizehints(Client *c);		/* update the size hint variables of c */
111extern void updatetitle(Client *c);		/* update the name of c */
112extern void unmanage(Client *c);		/* destroy c */
113
114/* draw.c */
115extern void drawstatus(void);			/* draw the bar */
116extern unsigned long getcolor(const char *colstr);	/* return color of colstr */
117extern void setfont(const char *fontstr);	/* set the font for DC */
118extern unsigned int textw(const char *text);	/* return the width of text in px*/
119
120/* event.c */
121extern void grabkeys(void);			/* grab all keys defined in config.h */
122extern void procevent(void);			/* process pending X events */
123
124/* main.c */
125extern int getproto(Window w);			/* return protocol mask of WMProtocols property of w */
126extern void quit(Arg *arg);			/* quit dwm nicely */
127extern void sendevent(Window w, Atom a, long value);	/* send synthetic event to w */
128extern int xerror(Display *dsply, XErrorEvent *ee);	/* dwm's X error handler */
129
130/* tag.c */
131extern void initrregs(void);			/* initialize regexps of rules defined in config.h */
132extern Client *getnext(Client *c);		/* returns next visible client */
133extern Client *getprev(Client *c);		/* returns previous visible client */
134extern void settags(Client *c, Client *trans);	/* sets tags of c */
135extern void tag(Arg *arg);			/* tags c with arg's index */
136extern void toggletag(Arg *arg);		/* toggles c tags with arg's index */
137
138/* util.c */
139extern void *emallocz(unsigned int size);	/* allocates zero-initialized memory, exits on error */
140extern void eprint(const char *errstr, ...);	/* prints errstr and exits with 1 */
141extern void spawn(Arg *arg);			/* forks a new subprocess with to arg's cmd */
142
143/* view.c */
144extern void detach(Client *c);			/* detaches c from global client list */
145extern void dofloat(void);			/* arranges all windows floating */
146extern void dotile(void);			/* arranges all windows tiled */
147extern void focusnext(Arg *arg);		/* focuses next visible client, arg is ignored  */
148extern void focusprev(Arg *arg);		/* focuses previous visible client, arg is ignored */
149extern void incnmaster(Arg *arg);		/* increments nmaster with arg's index value */
150extern Bool isvisible(Client *c);		/* returns True if client is visible */
151extern void resizemaster(Arg *arg);		/* resizes the master percent with arg's index value */
152extern void restack(void);			/* restores z layers of all clients */
153extern void togglefloat(Arg *arg);		/* toggles focusesd client between floating/non-floating state */
154extern void togglemode(Arg *arg);		/* toggles global arrange function (dotile/dofloat) */
155extern void toggleview(Arg *arg);		/* toggles the tag with arg's index (in)visible */
156extern void view(Arg *arg);			/* views the tag with arg's index */
157extern void zoom(Arg *arg);			/* zooms the focused client to master area, arg is ignored */