1 files changed, 79 insertions, 0 deletions
diff --git a/share/mk/meta.subdir.mk b/share/mk/meta.subdir.mk
new file mode 100644
index 000000000000..1a77b44abc3c
--- /dev/null
+++ b/share/mk/meta.subdir.mk
@@ -0,0 +1,79 @@
+# $Id: meta.subdir.mk,v 1.8 2011/11/09 22:27:25 sjg Exp $
+
+#
+#	@(#) Copyright (c) 2010, Simon J. Gerraty
+#
+#	This file is provided in the hope that it will
+#	be of use.  There is absolutely NO WARRANTY.
+#	Permission to copy, redistribute or otherwise
+#	use this file is hereby granted provided that 
+#	the above copyright notice and this notice are
+#	left intact. 
+#      
+#	Please send copies of changes and bug-fixes to:
+#	sjg@crufty.net
+#
+
+.if !defined(NO_SUBDIR) && !empty(SUBDIR)
+.if make(destroy*) || make(clean*)
+.MAKE.MODE = compat
+.if !commands(destroy)
+.-include <bsd.obj.mk>
+.endif
+.elif ${.MAKE.LEVEL} == 0
+
+.MAIN: all
+
+.if !exists(${.CURDIR}/${.MAKE.DEPENDFILE:T}) || make(gendirdeps)
+# start with this
+DIRDEPS = ${SUBDIR:N.WAIT:O:u:@d@${RELDIR}/$d@}
+
+.if make(gendirdeps)
+.include <meta.autodep.mk>
+.else
+# this is the cunning bit
+# actually it is probably a bit risky 
+# since we may pickup subdirs which are not relevant
+# the alternative is a walk through the tree though
+# which is difficult without a sub-make.
+
+.if defined(BOOTSTRAP_DEPENDFILES)
+_find_name = ${.MAKE.MAKEFILE_PREFERENCE:@m@-o -name $m@:S,^-o,,1}
+DIRDEPS = ${_subdeps:H:O:u:@d@${RELDIR}/$d@}
+.elif ${.MAKE.DEPENDFILE:E} == ${MACHINE} && defined(ALL_MACHINES)
+# we want to find Makefile.depend.* ie for all machines
+# and turn the dirs into dir.<machine>
+_find_name = -name '${.MAKE.DEPENDFILE:T:R}*'
+DIRDEPS = ${_subdeps:O:u:${NIgnoreFiles}:@d@${RELDIR}/${d:H}.${d:E}@:S,.${MACHINE}$,,:S,.depend$,,}
+.else
+# much simpler
+_find_name = -name ${.MAKE.DEPENDFILE:T}
+.if ${.MAKE.DEPENDFILE:E} == ${MACHINE}
+_find_name += -o -name ${.MAKE.DEPENDFILE:T:R}
+.endif
+DIRDEPS = ${_subdeps:H:O:u:@d@${RELDIR}/$d@}
+.endif
+
+_subdeps != cd ${.CURDIR} && \
+	find ${SUBDIR:N.WAIT} -type f \( ${_find_name} \) -print -o \
+	-name .svn -prune 2> /dev/null; echo
+
+.if empty(_subdeps)
+DIRDEPS =
+.else
+# clean up if needed
+DIRDEPS := ${DIRDEPS:S,^./,,:S,/./,/,g:${SUBDIREPS_FILTER:Uu}}
+.endif
+# we just dealt with it, if we leave it defined,
+# dirdeps.mk will compute some interesting combinations.
+.undef ALL_MACHINES
+
+DEP_RELDIR = ${RELDIR}
+.include <dirdeps.mk>
+.endif
+.endif
+.else
+all: .PHONY
+.endif
+
+.endif