Re: broken references in jar manifests

[Ludovic Courtès]

Heya,

Ricardo Wurmus <address@hidden> skribis:

> Manifest-Version: 1.0
> Class-Path: /gnu/store/i28vi94r8z9f0x02zgkrv87w16ibmqkw-java-htsjdk-2.
>  10.1/share/java/htsjdk.jar
> Created-By: 1.8.0_151 (Oracle Corporation)
> Main-Class: picard.cmdline.PicardCommandLine
>
> Note that the Class-Path property is broken into two lines.  This means
> that the reference scanner will miss it and grafting will fail.
>
> Breaking up lines longer than 70 characters is according to the manifest
> specification, see
> https://docs.oracle.com/javase/7/docs/technotes/guides/jar/jar.html

What would happen if we modified the tool that generates these to no
break lines?  Buffer overflow in the class loader?

> 1) we need to patch the JDK
> 2) the jars would not do the right thing when executed with a different
> JDK (e.g. on a foreign distro).

Does #2 really matter?  Those jars won’t work on non-Guix systems anyway
precisely because they contain references to the store.

> An alternative to recording full references in the manifest file is to
> install a “lib” directory that contains symlinks to dependencies.  The
> manifest can then contain relative paths to these symlinks.

Very smart and easy to do, no?  To my untrained eye, this looks like the
winning option here.  :-)

Thanks,
Ludo’.