[dwm] Adapted the pertag patch for 5.0.1

[Mayhem 666]

Greetings to all

This is my first attempt to improve-modify existing open source, so please
forgive any
imperfections or errors. I believe the patch i send applied to 5.0.1 to be
free of any bugs.
It is a simple adaptation of the pertag patch which was at the site to the
new version of dwm.
A friend asked me to write it so i worked with the existing patch.
Hopefully the project maintainer can update the web site with this fixed
version.

Thanks in advance.

diff -up dwm-5.0.1/dwm.c dwm-5.0.1.pertag/dwm.c
--- dwm.c	2008-06-19 11:11:38.000000000 +0300
+++ dwm.c	2008-07-08 23:17:30.000000000 +0300
@@ -237,6 +237,8 @@ static Display *dpy;
 static DC dc = {0};
 static Layout *lt = NULL;
 static Window root, barwin;
+static Layout **ptlt;
+static double *mfacts;
 /* configuration, allows nested code to access above variables */
 #include "config.h"
 
@@ -272,7 +274,10 @@ applyrules(Client *c) {
 void
 arrange(void) {
 	Client *c;
+	int i;
 
+	for(i = 0; i < LENGTH(tags) && !(tagset[seltags] & 1 << i); i++);
+	lt = ptlt[i];		/* The first visible tag defines the layout */
 	for(c = clients; c; c = c->next)
 		if(c->tags & tagset[seltags]) { /* is visible */
 			if(ismax && !c->isfixed) {
@@ -1300,6 +1305,7 @@ setclientstate(Client *c, long state) {
 void
 setmfact(const Arg *arg) {
 	float f;
+	int i;
 
 	if(!arg || !lt->arrange)
 		return;
@@ -1307,6 +1313,9 @@ setmfact(const Arg *arg) {
 	if(f < 0.1 || f > 0.9)
 		return;
 	mfact = f;
+	for(i = 0; i < LENGTH(tags); i++)
+		if(tagset[seltags] & 1 << i)
+			mfacts[i] = mfact;		/* Adjust all visible tags mfact */
 	arrange();
 }
 
@@ -1328,6 +1337,16 @@ setup(void) {
 	lt = layouts;
 	updategeom();
 
+	/* init mfacts array and ptlt array */
+	if(!(mfacts = calloc(LENGTH(tags), sizeof(double))))
+		eprint("Fatal: could not calloc() %d bytes\n", LENGTH(tags) * sizeof(double) );
+	for(i = 0; i < LENGTH(tags); i++)
+	  	mfacts[i] = mfact;
+	if(!(ptlt = calloc(LENGTH(tags), sizeof(Layout*))))
+		eprint("Fatal: could not calloc() %d bytes\n", LENGTH(tags) * sizeof(Layout *) );
+	for(i = 0; i < LENGTH(tags); i++)
+		ptlt[i] = lt;
+
 	/* init atoms */
 	wmatom[WMProtocols] = XInternAtom(dpy, "WM_PROTOCOLS", False);
 	wmatom[WMDelete] = XInternAtom(dpy, "WM_DELETE_WINDOW", False);
@@ -1436,7 +1455,8 @@ tile(void) {
 
 	/* master */
 	c = nexttiled(clients);
-	mw = mfact * ww;
+	for(i = 0; i<LENGTH(tags) && !(tagset[seltags] & 1 << i); i++);	/* Select mfact from first visible tag */
+	mw = mfacts[i] * ww;
 	resize(c, wx, wy, (n == 1 ? ww : mw) - 2 * c->bw, wh - 2 * c->bw, resizehints);
 
 	if(--n == 0)
@@ -1480,8 +1500,13 @@ void
 togglelayout(const Arg *arg) {
 	if(arg && arg->v)
 		lt = (Layout *)arg->v;
-	else if(++lt == &layouts[LENGTH(layouts)])
-		lt = &layouts[0];
+	else {
+		int i;
+		for(i = 0; i<LENGTH(tags); i++)
+			if( tagset[seltags] & 1 << i )
+				if( ++ptlt[i] == &layouts[LENGTH(layouts)] )
+					ptlt[i] = layouts;
+	} 
 	if(sel)
 		arrange();
 	else