[hackers] [dwm][PATCH] preserve clients on old tags when renewing dwm

[Arda Atci]

---
 dwm.c | 38 +++++++++++++++++++++++++++++++++++++-
 1 file changed, 37 insertions(+), 1 deletion(-)

diff --git a/dwm.c b/dwm.c
index a96f33c..a12e0bd 100644
--- a/dwm.c
+++ b/dwm.c
@@ -62,7 +62,7 @@ enum { CurNormal, CurResize, CurMove, CurLast }; /* cursor */
 enum { SchemeNorm, SchemeSel }; /* color schemes */
 enum { NetSupported, NetWMName, NetWMState, NetWMCheck,
        NetWMFullscreen, NetActiveWindow, NetWMWindowType,
-       NetWMWindowTypeDialog, NetClientList, NetLast }; /* EWMH atoms */
+       NetWMWindowTypeDialog, NetClientList, NetClientInfo, NetLast }; /* EWMH 
atoms */
 enum { WMProtocols, WMDelete, WMState, WMTakeFocus, WMLast }; /* default atoms 
*/
 enum { ClkTagBar, ClkLtSymbol, ClkStatusText, ClkWinTitle,
        ClkClientWin, ClkRootWin, ClkLast }; /* clicks */
@@ -198,6 +198,7 @@ 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 setclienttagprop(Client *c);
 static void setfocus(Client *c);
 static void setfullscreen(Client *c, int fullscreen);
 static void setlayout(const Arg *arg);
@@ -1060,6 +1061,26 @@ manage(Window w, XWindowAttributes *wa)
        updatewindowtype(c);
        updatesizehints(c);
        updatewmhints(c);
+       {
+               int format;
+               unsigned long *data, n, extra;
+               Monitor *m;
+               Atom atom;
+               if (XGetWindowProperty(dpy, c->win, netatom[NetClientInfo], 0L, 
2L, False, XA_CARDINAL,
+                               &atom, &format, &n, &extra, (unsigned char 
**)&data) == Success && n == 2) {
+                       c->tags = *data;
+                       for (m = mons; m; m = m->next) {
+                               if (m->num == *(data+1)) {
+                                       c->mon = m;
+                                       break;
+                               }
+                       }
+               }
+               if (n > 0)
+                       XFree(data);
+       }
+       setclienttagprop(c);
+
        XSelectInput(dpy, w, 
EnterWindowMask|FocusChangeMask|PropertyChangeMask|StructureNotifyMask);
        grabbuttons(c, 0);
        if (!c->isfloating)
@@ -1423,6 +1444,7 @@ sendmon(Client *c, Monitor *m)
        c->tags = m->tagset[m->seltags]; /* assign tags of target monitor */
        attach(c);
        attachstack(c);
+       setclienttagprop(c);
        focus(NULL);
        arrange(NULL);
 }
@@ -1566,6 +1588,7 @@ setup(void)
        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);
+       netatom[NetClientInfo] = XInternAtom(dpy, "_NET_CLIENT_INFO", False);
        /* init cursors */
        cursor[CurNormal] = drw_cur_create(drw, XC_left_ptr);
        cursor[CurResize] = drw_cur_create(drw, XC_sizing);
@@ -1589,6 +1612,7 @@ setup(void)
        XChangeProperty(dpy, root, netatom[NetSupported], XA_ATOM, 32,
                PropModeReplace, (unsigned char *) netatom, NetLast);
        XDeleteProperty(dpy, root, netatom[NetClientList]);
+       XDeleteProperty(dpy, root, netatom[NetClientInfo]);
        /* select events */
        wa.cursor = cursor[CurNormal]->cursor;
        wa.event_mask = SubstructureRedirectMask|SubstructureNotifyMask
@@ -1656,11 +1680,22 @@ spawn(const Arg *arg)
        }
 }
 
+void
+setclienttagprop(Client *c)
+{
+       long data[] = { (long) c->tags, (long) c->mon->num };
+       XChangeProperty(dpy, c->win, netatom[NetClientInfo], XA_CARDINAL, 32,
+                       PropModeReplace, (unsigned char *) data, 2);
+}
+
 void
 tag(const Arg *arg)
 {
+       Client *c;
        if (selmon->sel && arg->ui & TAGMASK) {
+               c = selmon->sel;
                selmon->sel->tags = arg->ui & TAGMASK;
+               setclienttagprop(c);
                focus(NULL);
                arrange(selmon);
        }
@@ -1735,6 +1770,7 @@ toggletag(const Arg *arg)
        newtags = selmon->sel->tags ^ (arg->ui & TAGMASK);
        if (newtags) {
                selmon->sel->tags = newtags;
+               setclienttagprop(selmon->sel);
                focus(NULL);
                arrange(selmon);
        }
-- 
2.36.1