makepkg: fix regression that broke extraction of file:// sources

In commit 9c817b6549 we made these sources
extendable, and heuristically determined the correct extraction
functions to use. But our fallback for protos that didn't have an exact
extract_* function didn't take into account that 'extract_file' matches
an actual proto... so we passed the netfile in while the function
expected a file.

Solution: the function should expect a netfile too, thereby allowing us
to delay an attempted resolution of netfile -> file, to the one case
where it is actually used. This makes us slightly more efficient in the
non-file case, makes our functions a bit more consistent, and makes
file:// extraction work again.

Fixes FS#64648

Signed-off-by: Eli Schwartz <eschwartz@archlinux.org>
Signed-off-by: Allan McRae <allan@archlinux.org>
(cherry picked from commit 349c22d043)

scripts/libmakepkg/source.sh.in

@@ -75,12 +75,11 @@ extract_sources() {
 
 	get_all_sources_for_arch 'all_sources'
 	for netfile in "${all_sources[@]}"; do
-		local file=$(get_filename "$netfile")
 		local proto=$(get_protocol "$netfile")
 		if declare -f extract_$proto > /dev/null; then
 			extract_$proto "$netfile"
 		else
-			extract_file "$file"
+			extract_file "$netfile"
 		fi
 	done
 }

scripts/libmakepkg/source/file.sh.in

@@ -83,8 +83,9 @@ download_file() {
 }
 
 extract_file() {
-	local file=$1
+	local netfile=$1
 
+	local file=$(get_filename "$netfile")
 	local filepath=$(get_filepath "$file")
 	rm -f "$srcdir/${file}"
 	ln -s "$filepath" "$srcdir/"