From 4ecf33f469cb494be10d6c757753a5104f975627 Mon Sep 17 00:00:00 2001
From: Luke Smith <luke@lukesmith.xyz>
Date: Wed, 2 Nov 2022 12:53:16 -0400
Subject: preserveonrestart

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

diff --git a/dwm.c b/dwm.c
index 33bb71c..041e0d8 100644
--- a/dwm.c
+++ b/dwm.c
@@ -90,7 +90,7 @@ 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 */
@@ -251,6 +251,7 @@ 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);
@@ -1283,6 +1284,26 @@ 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);
+
 	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);
@@ -1681,6 +1702,7 @@ 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);
 }
@@ -1857,6 +1879,7 @@ 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);
@@ -1880,6 +1903,7 @@ 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
@@ -1982,11 +2006,22 @@ 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);
 	}
@@ -2075,6 +2110,7 @@ toggletag(const Arg *arg)
 	newtags = selmon->sel->tags ^ (arg->ui & TAGMASK);
 	if (newtags) {
 		selmon->sel->tags = newtags;
+		setclienttagprop(selmon->sel);
 		focus(NULL);
 		arrange(selmon);
 	}
-- 
cgit 1.4.1