Add support for out-of-tree builds

Involves prefixing with $(srcdir) to some of the build rule variables. For
the builddir we create Makefiles which simply include the srcdir Makefile.
Add list make rule to get list of Makefiles to generate (find will get it
wrong for builddirs nested in srcdir).

There are still a few minor issues like the file paths echoed during make
install ...

Makefile.lib

@@ -56,7 +56,7 @@ ifdef OBJS
 -include $(DEP_FILES)
 endif
 
-%.o: %.c
+%.o: $(srcdir)%.c
 	$(call mcmd,compile)
 	@-cp .deps/$(*F).pp .deps/$(*F).P; \
 		tr ' ' '\012' < .deps/$(*F).pp \
@@ -84,6 +84,9 @@ CLEAN += $(PROG)
 
 all-default: $(LIB_O) $(PROGS) $(MAN1) $(MAN5)
 
+list-default:
+	@echo '$(RELPATH)Makefile'
+
 clean-default:
 	-test -z "$(CLEAN)" || $(RM) $(CLEAN)
 
@@ -106,8 +109,8 @@ endif
 
 # Recursion:
 
-.PHONY: all-recursive install-recursive clean-recursive
-all-recursive install-recursive clean-recursive:
+.PHONY: all-recursive install-recursive clean-recursive list-recursive
+all-recursive install-recursive clean-recursive list-recursive:
 ifdef SUBDIRS
 	@target=`echo $@ | sed s/-recursive//`; \
 	for subdir in $(sort $(SUBDIRS)); do \
@@ -118,6 +121,7 @@ endif
 all: all-recursive all-default all-local
 install: install-recursive install-default install-local
 clean: clean-recursive clean-default clean-local
+list: list-recursive list-default
 
 all-local:
 install-local:

configure.in

@@ -1245,6 +1245,19 @@ AC_OUTPUT([ \
  src/intl/gettext/ref-del.sed
 ])
 
+srcdir2="$(cd "$srcdir" && pwd)"
+if test "$srcdir2" != "$builddir"; then
+	for i in $(make -C "$srcdir" list | grep Makefile); do
+		$MKINSTALLDIRS "$builddir/$(dirname $i)"
+		grep path_to_top= "$srcdir/$i" > "$builddir/$i"
+		case "$srcdir" in
+		/*)	echo "include $srcdir/$i" >> "$builddir/$i" ;;
+		*)	echo "include \$(path_to_top)/$srcdir/$i" >> "$builddir/$i" ;;
+		esac
+		echo "creating $builddir/$i"
+	done
+fi
+ 
 
 dnl ===================================================================
 dnl Configuration summary

doc/man/man1/Makefile

@@ -1,7 +1,7 @@
 path_to_top=../../..
 include $(path_to_top)/Makefile.config
 
-elinks.1: elinks.1.in $(top_srcdir)/configure.in
+elinks.1: $(srcdir)/elinks.1.in $(top_srcdir)/configure.in
 	cd $(top_srcdir) && \
 	CONFIG_FILES="$(RELPATH)$@" CONFIG_HEADERS= $(SHELL) ./config.status
 

doc/man/man5/Makefile

@@ -1,6 +1,6 @@
 path_to_top=../../..
 include $(path_to_top)/Makefile.config
 
-MAN5 = elinks.conf.5 elinkskeys.5
+MAN5 = $(srcdir)/elinks.conf.5 $(srcdir)/elinkskeys.5
 
 include $(top_srcdir)/Makefile.lib

po/Makefile

@@ -15,7 +15,7 @@ POTFILES_ABS_LIST = potfiles.list
 SUFFIXES = .po .gmo .mo
 .SUFFIXES: .gmo .mo .po
 
-%.gmo: %.po
+%.gmo: $(srcdir)/%.po
 	@file=`echo $* | sed 's,.*/,,'`.gmo \
 	  && rm -f $$file && echo -n $*": " \
 	  && $(GMSGFMT) --statistics -o $$file $<

src/intl/gettext/Makefile

@@ -4,9 +4,6 @@ include $(path_to_top)/Makefile.config
 localedir = $(datadir)/locale
 builddir = $(top_builddir)/src/intl/gettext
 
-# FIXME: Makefile.config gets this wrong
-srcdir = $(top_srcdir)/src/intl/gettext
-
 OBJS = \
  bindtextdom.o \
  dcgettext.o \