xborderless.c

#include "xborderless.h"
#include <stdio.h>

#ifdef DEBUG
#define debug(a...) fprintf(stderr,a)
#else
#define debug(a...) do {} while(0)
#endif

static int down_x, down_y;

static void btndown(Widget w, XEvent* e, String* s, Cardinal* n)
{
    int x,y,x0=e->xbutton.x, y0= e->xbutton.y;
    Display *disp = XtDisplay(w);
    Window child_return;
    Widget par = w;
    while( XtParent(par) ) par = XtParent(par);

    XTranslateCoordinates (disp, XtWindow(w), XtWindow(par),
                           x0, y0, & x, & y, & child_return);

    down_x = x;
    down_y = y;
}

static void btnmove(Widget w, XEvent* e, String* s, Cardinal* n)
{
    int x0=e->xbutton.x, y0= e->xbutton.y;

    Display *disp = XtDisplay(w);
    int screen    = DefaultScreen(disp);
    Window root   = RootWindow(disp,screen);
    int x,y;
    Window child_return;
    Widget par;

    XTranslateCoordinates (disp, XtWindow(w), root,
                           x0, y0, & x, & y, & child_return);
    while( (par = XtParent(w)) ) w=par;
    XMoveWindow(disp,XtWindow(w), x - down_x,y-down_y );
}



/** append to the list of client properties a property that
    tells the window manager to keep this window above others
*/
void make_stay_above(Widget top)
{
#define _NET_WM_STATE_REMOVE        0    // remove/unset property
#define _NET_WM_STATE_ADD           1    // add/set property
#define _NET_WM_STATE_TOGGLE        2    // toggle property

    Display *display = XtDisplay(top);
    int screen = DefaultScreen(display);
    Window root = RootWindow(display,screen);
    Atom wmStateAbove;
    Atom wmNetWmState;
    XClientMessageEvent xclient;
    memset( &xclient, 0, sizeof (xclient) );

    wmStateAbove = XInternAtom( display, "_NET_WM_STATE_ABOVE", 1 );
    if( wmStateAbove != None ) {
        debug( "_NET_WM_STATE_ABOVE has atom of %ld\n", (long)wmStateAbove );
    } else {
        debug( "ERROR: cannot find atom for _NET_WM_STATE_ABOVE !\n" );
    }

    wmNetWmState = XInternAtom( display, "_NET_WM_STATE", 1 );
    if( wmNetWmState != None ) {
        debug( "_NET_WM_STATE has atom of %ld\n", (long)wmNetWmState );
    } else {
        debug( "ERROR: cannot find atom for _NET_WM_STATE !\n" );
    }
    // set window always on top hint
    if( wmStateAbove == None ) return;


    //
    //window  = the respective client window
    //message_type = _NET_WM_STATE
    //format = 32
    //data.l[0] = the action, as listed below
    //data.l[1] = first property to alter
    //data.l[2] = second property to alter
    //data.l[3] = source indication (0-unk,1-normal app,2-pager)
    //other data.l[] elements = 0
    //
    xclient.type = ClientMessage;
    xclient.window = XtWindow(top); // GDK_WINDOW_XID(window);
    xclient.message_type = wmNetWmState; //gdk_x11_get_xatom_by_name_for_display( display, "_NET_WM_STATE" );
    xclient.format = 32;
    xclient.data.l[0] = _NET_WM_STATE_ADD; // add ? _NET_WM_STATE_ADD : _NET_WM_STATE_REMOVE;
    xclient.data.l[1] = wmStateAbove; //gdk_x11_atom_to_xatom_for_display (display, state1);
    xclient.data.l[2] = 0; //gdk_x11_atom_to_xatom_for_display (display, state2);
    xclient.data.l[3] = 0;
    xclient.data.l[4] = 0;
    //  gdk_wmspec_change_state( FALSE, window,
    //  gdk_atom_intern_static_string ("_NET_WM_STATE_BELOW"),
    //  GDK_NONE );
    XSendEvent( display,
                //mywin - wrong, not app window, send to root window!
                root, // !! DefaultRootWindow( display ) !!!
                False,
                SubstructureRedirectMask | SubstructureNotifyMask,
                (XEvent *)&xclient );
}

/** tell window manager to not decorated this shell window
 */
void make_borderless_window(Widget top )
{
    Window window = XtWindow(top);
    Display *display = XtDisplay(top);

    struct MwmHints {
        unsigned long flags;
        unsigned long functions;
        unsigned long decorations;
        long input_mode;
        unsigned long status;
    };

    enum {
        MWM_HINTS_FUNCTIONS = (1L << 0),
        MWM_HINTS_DECORATIONS =  (1L << 1),

        MWM_FUNC_ALL = (1L << 0),
        MWM_FUNC_RESIZE = (1L << 1),
        MWM_FUNC_MOVE = (1L << 2),
        MWM_FUNC_MINIMIZE = (1L << 3),
        MWM_FUNC_MAXIMIZE = (1L << 4),
        MWM_FUNC_CLOSE = (1L << 5)
    };
    struct MwmHints hints;
    Atom mwmHintsProperty = XInternAtom(display, "_MOTIF_WM_HINTS", 0);

    hints.flags = MWM_HINTS_DECORATIONS;
    hints.decorations = 0;
    XChangeProperty(display, window, mwmHintsProperty, mwmHintsProperty, 32,
                    PropModeReplace, (unsigned char *)&hints, 5);
}

static void wm_quit(Widget w, XEvent *event, String *params, Cardinal *num_params)
{

    XtAppSetExitFlag( XtWidgetToApplicationContext(w) );
}


/* add btnmove/btndown actions to application,
   override Btn1Motion / Btn1Down translations on widget |w|
*/
void add_winmove_translations(Widget w)
{
    static Boolean not_initialized = True;
    static XtTranslations app_translations;
    XtActionsRec action_table [] = {
        { "wm_quit", wm_quit },
        { "btndown",btndown },
        { "btnmove",btnmove }
    };

    char translation_str[] =
        " <Btn2Down>: wm_quit() \n"
        " <BtnMotion>: btnmove() \n"
        " <BtnDown>: btndown() \n";


    if( not_initialized ) {
        XtAppContext ctx = XtWidgetToApplicationContext(w);
        XtAppAddActions(ctx, action_table, XtNumber(action_table) );
        app_translations = XtParseTranslationTable(translation_str);
        not_initialized = False;
    }
    XtOverrideTranslations( w, app_translations );
}