relativise symbolic links

[id3fs.git] / lib / ID3FS / DB.pm

diff --git a/lib/ID3FS/DB.pm b/lib/ID3FS/DB.pm
index 15855b2..9930609 100644 (file)
--- a/lib/ID3FS/DB.pm
+++ b/lib/ID3FS/DB.pm
@@ -385,7 +385,7 @@ sub tracks
 
 sub filename
 {
-    my($self, @constraints)=@_;
+    my($self, $mountpoint, @constraints)=@_;
     if(ref($constraints[$#constraints]) eq "ID3FS::PathElement::File")
     {
        my $id=$constraints[$#constraints]->{id};
@@ -395,11 +395,45 @@ sub filename
                 "GROUP BY paths.name, files.name");
        print "FILENAME SQL: $sql\n";
        my ($path, $name)=$self->cmd_onerow($sql, $id);
-       return($self->{absbase} . "/$path/$name");
+       my $id3fs_path=join('/', map { $_->{name}; }  @constraints);
+       return($self->relativise($path, $name, $mountpoint, $id3fs_path));
     }
     die("DB::filename: unhandled case\n"); #FIXME
 }
 
+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 $result;
+}
+
 sub bare_tags
 {
     my($self)=@_;