Binary Serialized File - Delphi

Question

I am trying to deserialize an old file format that was serialized in Delphi, it uses binary seralization. I know nothing about the structure of the file except some very high level records that are in it.

What steps would you take to solve this problem? Any tools etc?

Answer 1

A good hexeditor, and use the gray matter to identify structures.

If you get a hint what kind of file it is, you can search for more specialized tools.

Running the unix/Linux "file" command can be good too (*) See Barry's comment below for how it works. It can be a quick check for common filetypes like DBF,ZIP etc hidden by using a different extension.

(*) there are 3rd party builds for windows, but they might lag in versions. If you can do it on a recent *nix distro, it is advised to do so.

Answer 2

The serialization process simply loops over all published properties and streams their value to a text file. If you do not know the exact classes that were streamed to the file you will have a very hard time deserializing the file. (if not impossible)

Answer 3

A good hex editor is first. If the file is read without buffering (eg read directly from a TFileStream) you could gain some information when using ProcMon from SysInternals; You can see exactly what data is read in what chunks and thus determine more quickly where the boundaries are between the structures you already identified.