+
+ if (not @source and not @versions and not @archs) {
+ # ok, we haven't found any results at all. If we weren't given
+ # a specific version and architecture, then we should try
+ # really hard to figure out the right source
+
+ # if any the packages we've been given are a valid source
+ # package name, and there's no binary of the same name (we got
+ # here, so there isn't), return it.
+
+ if (not tied %_sourcetobinary) {
+ tie %_sourcetobinary, MLDBM => $config{source_binary_map}, O_RDONLY or
+ die "Unable top open $gSourceBinaryMap for reading";
+ }
+ for my $maybe_sourcepkg (@binaries) {
+ if (exists $_sourcetobinary{$maybe_sourcepkg}) {
+ push @source,[$maybe_sourcepkg,$_] for keys %{$_sourcetobinary{$maybe_sourcepkg}};
+ }
+ }
+ # if @source is still empty here, it's probably a non-existant
+ # source package, so don't return anything.
+ }
+