port dwm "push" patch to dwl

Makefile

@@ -16,7 +16,7 @@ LDLIBS    = `$(PKG_CONFIG) --libs $(PKGS)` $(LIBS)
 all: dwl
 dwl: dwl.o util.o
 	$(CC) dwl.o util.o $(LDLIBS) $(LDFLAGS) $(DWLCFLAGS) -o $@
-dwl.o: dwl.c config.mk config.h client.h xdg-shell-protocol.h wlr-layer-shell-unstable-v1-protocol.h
+dwl.o: dwl.c push.c config.mk config.h client.h xdg-shell-protocol.h wlr-layer-shell-unstable-v1-protocol.h
 util.o: util.c util.h
 
 # wayland-scanner is a tool which generates C headers and rigging for Wayland

dwl.c

@@ -370,7 +370,9 @@ static Atom netatom[NetLast];
 #endif
 
 /* configuration, allows nested code to access above variables */
+#include "push.h"
 #include "config.h"
+#include "push.c"
 
 /* attempt to encapsulate suck into one file */
 #include "client.h"

push.c

@@ -0,0 +1,63 @@
+static Client *
+nexttiled(Client *sel) {
+	Client *c;
+	wl_list_for_each(c, &sel->link, link) {
+		if (&c->link == &clients)
+			break;  /* don't wrap */
+		if (!c->isfloating && VISIBLEON(c, selmon))
+			return c;
+	}
+	return NULL;
+}
+
+static Client *
+prevtiled(Client *sel) {
+	Client *c;
+	wl_list_for_each_reverse(c, &sel->link, link) {
+		if (&c->link == &clients)
+			break;  /* don't wrap */
+		if (!c->isfloating && VISIBLEON(c, selmon))
+			return c;
+	}
+	return NULL;
+}
+
+static void
+pushup(const Arg *arg) {
+	Client *sel = selclient();
+	Client *c;
+
+	if(!sel || sel->isfloating)
+		return;
+	if((c = prevtiled(sel))) {
+		/* attach before c */
+		wl_list_remove(&sel->link);
+		wl_list_insert(c->link.prev, &sel->link);
+	} else {
+		/* move to the end */
+		wl_list_remove(&sel->link);
+		wl_list_insert(clients.prev, &sel->link);
+	}
+	focusclient(sel, 1);
+	arrange(selmon);
+}
+
+static void
+pushdown(const Arg *arg) {
+	Client *sel = selclient();
+	Client *c;
+
+	if(!sel || sel->isfloating)
+		return;
+	if((c = nexttiled(sel))) {
+		/* attach after c */
+		wl_list_remove(&sel->link);
+		wl_list_insert(&c->link, &sel->link);
+	} else {
+		/* move to the front */
+		wl_list_remove(&sel->link);
+		wl_list_insert(&clients, &sel->link);
+	}
+	focusclient(sel, 1);
+	arrange(selmon);
+}