Framework for "container" files

[larsbrinkhoff]

Create a framework for "container" files similar to work and file formats. A "container" in this context is a file or other medium containing other files. Common operations on containers are:

• Listing files.
• Extracting all or a selection of files.
• Creating a new container from a list of files.
• Removing/adding/updating files in a container.

Currently supported container formats with ad-hoc support:

• DECtape MACDMP format.
• Raw magtapes (tape mark separated files).
• ITS DUMP tapes.
• ITS MAGDMP tapes.
• ITS file systems on disks.
• TENEX/TOPS-20 DUMPER tapes.
• WAITS DART tapes.
• TENCOM-X TITO tapes.
• ITS archive files.
• IPAK archives.
• BSYS tapes (work in progress).

[larsbrinkhoff]

Future extension, but not an immediate goal, would be to have other tools operate on a file inside a container. E.g. disassemble a single file on a tape.

[larsbrinkhoff]

Pie in the sky. Generalize this to "containers in containers" to any depth.

The default top-level container would be the local host file system.

[atsampson]

I'd like eventually to add support for Multics tapes and archives as well (which aren't PDP-10, but are 36-bit, so the framework here would be useful).

[atsampson]

Also pie in the sky: provide a library to generate a container on the fly from a directory of files, so you could just attach a directory to a tape drive in an emulator and have it produce a tape automatically when read.

[larsbrinkhoff]

Multics is welcome here. I already diverged from 36-bitness by adding some 8-bit and 16-bit based formats. Really, any word size should work as long as it fits in a word_t (minus some tape metadata bits).

[larsbrinkhoff]

The idea to provide a library is interesting. More generally, various components could be packaged up as stand-alone libraries. We can quickly identify a few of those:

• Word format.
• Core image file format.
• Container format.
• Disassembler.