--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mk/subdir-rules.sh	Sat Dec 22 17:52:45 2007 -0500
@@ -0,0 +1,56 @@
+#!/bin/sh
+# subdir-rules.sh - generate make rules for subdir.mk
+# usage: subdir-rules.sh "targets" "subdirs" "moresubdirs" > rules.mk
+
+if [ $# != 3 ]; then
+    echo "$0: usage: $0 'targets' 'subdirs' 'moresubdirs'" 1>&2
+    exit 1
+fi
+
+TARGETS="$1"
+SUBDIRS="$2"
+MORESUBDIRS="$3"
+
+# Remove anything from MORESUBDIRS that's already in DIRS
+MORESUBDIRS=`(echo 1 $SUBDIRS; echo 2 $MORESUBDIRS) | awk '
+    /^1 / { for (i=2;i<=NF;i++) seen[$i] = 1; }
+    /^2 / { for (i=2;i<=NF;i++) if (!seen[$i]) print $i; }
+'`
+
+for T in $TARGETS; do
+    if [ "$T" != rules -a "$T" != distclean ]; then
+	echo "${T}: ${T}-subdirs"
+    fi
+done
+
+for T in $TARGETS; do
+    echo "${T}-subdirs:"
+
+    if [ "$T" = rules -o "$T" = distclean ]; then
+	DIRS="$SUBDIRS $MORESUBDIRS"
+    else
+	DIRS="$SUBDIRS"
+    fi
+
+    for D in $DIRS; do
+	echo $D | awk '{
+	    printf "\t@echo \"%s ===> $(_SUBDIR_)%s\"\n", t, $1;
+	    printf "\t@cd %s && $(MAKE) %s _SUBDIR_=$(_SUBDIR_)%s/\n", $1,t,$1;
+	}' "t=$T"
+    done
+done
+
+for T in $TARGETS; do
+    echo ".PHONY: $T ${T}-subdirs"
+done
+
+echo 'distclean-here:'
+for D in $SUBDIRS $MORESUBDIRS; do
+    echo $D | awk '
+	{
+	    printf "\t@echo \"        [RMDIR]   %s\"\n", $1;
+	    printf "\t@-rm -f %s/Makefile %s/rules.mk %s/depend.mk\n",$1,$1,$1;
+	    printf "\t@-rmdir %s\n", $1;
+	}
+    '
+done