+sub tags_subselect
+{
+ my($self,@constraints)=@_;
+ my @ids = grep { defined; } map { $_->{id}; } @constraints;
+ @ids=map( { "\"$_\""; } @ids) unless($self->{postgres});
+ my $sql=("\tSELECT files_id FROM tags t1\n" .
+ "\tINNER JOIN files_x_tags ON t1.id=files_x_tags.tags_id\n" .
+ "\tWHERE t1.id IN (\n\t\t" .
+ join(', ', @ids) .
+ "\n\t)\n");
+ return $sql;
+}
+
+
+sub relativise
+{
+ my($self, $path, $name, $mountpoint, $id3fs_path)=@_;
+ $id3fs_path=~s/(.*)\/.*/$1/;
+ my $rpath="$self->{absbase}/$path";
+ my $vpath="$mountpoint/$id3fs_path";
+ my @path=split(/\//,$rpath);
+ my @rel=split(/\//,$vpath);
+ #absolute paths have empty first element due to leading /
+ shift(@path) if($path[0] eq "");
+ shift(@rel) if($rel[0] eq "");
+ if($path[0] ne $rel[0])
+ {
+ #no path in common, return absolute
+ print "FAIL: NO PATHS IN COMMON\n";
+ return $name;
+ }
+ # f: /home/foo/bar/baz.mp3
+ # r: /home/ianb/music/albums
+ while(@path && @rel && ($path[0] eq $rel[0]))
+ {
+ shift(@path);
+ shift(@rel);
+ print "POP ";
+ }
+ print "\n";
+ my $upcount=scalar(@rel);
+ my $result="../" x $upcount;
+ $result .= join("/",@path);
+ $result .= "/$name";
+ return $result;
+}
+