+ # Edit out `#line' or `#' directives.
+ #
+ # We don't want the resulting debug information to point at
+ # an absolute srcdir; it is better for it to just mention the
+ # .y file with no path.
+ #
+ # We want to use the real output file name, not yy.lex.c for
+ # instance.
+ #
+ # We want the include guards to be adjusted too.
+ FROM=`echo "$from" | sed \
+ -e 'y/abcdefghijklmnopqrstuvwxyz/ABCDEFGHIJKLMNOPQRSTUVWXYZ/'\
+ -e 's/[^ABCDEFGHIJKLMNOPQRSTUVWXYZ]/_/g'`
+ TARGET=`echo "$2" | sed \
+ -e 'y/abcdefghijklmnopqrstuvwxyz/ABCDEFGHIJKLMNOPQRSTUVWXYZ/'\
+ -e 's/[^ABCDEFGHIJKLMNOPQRSTUVWXYZ]/_/g'`
+
+ sed -e "/^#/!b" -e "s,$input_rx,," -e "s,$from,$2," \
+ -e "s,$FROM,$TARGET," "$from" >"$target" || ret=$?
+
+ # Check whether header files must be updated.
+ if test $first = no; then
+ if test -f "$realtarget" && cmp -s "$realtarget" "$target"; then
+ echo "$2" is unchanged
+ rm -f "$target"
+ else
+ echo updating "$2"
+ mv -f "$target" "$realtarget"
+ fi
+ fi
+ else
+ # A missing file is only an error for the first file. This
+ # is a blatant hack to let us support using "yacc -d". If -d
+ # is not specified, we don't want an error when the header
+ # file is "missing".
+ if test $first = yes; then
+ ret=1
+ fi
+ fi
+ shift
+ shift
+ first=no
+ done