Regenerate .conf files only if .conf.in were changed.

ChangeLog

@@ -59,6 +59,7 @@
 	  by the appropriate directories. This is especially useful for
 	  firmware locations. For the firmware paths for the artec_eplus48u,
 	  gt68xx, and snapscan backends variables were used. Bug #302590.
+	  Regenerate .conf files only if .conf.in were changed.
 	* backend/.cvsignore: Added *.conf.
 	* README.linux: Mentioned udev.
 	* doc/backend-writing.txt: New chapters about the build system and

backend/Makefile.in

@@ -170,8 +170,6 @@ DISTFILES = abaton.c abaton.conf.in abaton.h agfafocus.c agfafocus.conf.in \
   sm3840.conf.in sm3840.c sm3840_lib.c sm3840_params.h sm3840_scan.c sm3840.h \
   sm3840_lib.h
 
-
-
 .PHONY: all clean depend dist distclean install uninstall
 
 libsane-%.la: %.lo %-s.lo $(EXTRA) $(LIBOBJS)
@@ -286,21 +284,19 @@ libsane.la: dll.lo dll-s.lo $(EXTRA) $(addsuffix .lo,$(DLL_PRELOAD)) $(LIBOBJS)
 		$(addsuffix .lo,$(DLL_PRELOAD_EXTRAS)) @LIBTOOL_LINK_EXTRA@ \
 		-rpath $(libdir) -version-info $(V_MAJOR):$(V_REV):$(V_MINOR)
 
-becfg:
-	@for conf in $(CONFIGS) ; do \
-	   if test ! -f $${conf}.in ;  \
-	     then echo "Ignoring $${conf}" ;\
-	     continue; \
-	   fi ;\
-	   sed -e 's|@DATADIR@|$(datadir)|g' \
-	       -e 's|@CONFIGDIR@|$(configdir)|g' \
-	       -e 's|@DOCDIR@|$(docdir)|g' \
-	       -e 's|@LIBDIR@|$(libdir)/sane|g' \
-	       -e 's|@BINDIR@|$(bindir)|g' \
-	       -e 's|@SBINDIR@|$(sbindir)|g' \
-	       -e 's|@PACKAGEVERSION@|$(package_version)|g' $${conf}.in >$${conf} ;\
-	   echo Generating $${conf}... ;\
-	 done
+# Generate .conf files for all existing .conf.in files
+becfg: $(patsubst %.conf.in,%.conf,$(wildcard *.conf.in)) 
+%.conf: %.conf.in
+	@echo Generating $@ from $^
+	@sed -e 's|@DATADIR@|$(datadir)|g' \
+	     -e 's|@CONFIGDIR@|$(configdir)|g' \
+	     -e 's|@DOCDIR@|$(docdir)|g' \
+	     -e 's|@LIBDIR@|$(libdir)/sane|g' \
+	     -e 's|@BINDIR@|$(bindir)|g' \
+	     -e 's|@SBINDIR@|$(sbindir)|g' \
+	     -e 's|@PACKAGEVERSION@|$(package_version)|g' $? > $@
+
+
 
 # additional dependencies