bug#27143: [PATCH] gnu: build: Improve error reporting.

[Ludovic Courtès]

Hi Danny,

The prefix for the subject line should just be “file-systems:”.

Danny Milosavljevic <address@hidden> skribis:

> * gnu/build/file-systems.scm (read-iso9660-primary-volume-descriptor):
> Improve error reporting.

[...]

>     Return #f if not found."
>    (let* ((sblock    (read-superblock device offset 2048 iso9660-superblock?))
> -         (type-code (if sblock (array-ref sblock 0) 255)))
> +         (type-code (if sblock
> +                      (array-ref sblock 0)
> +                      (error (format #f "Could not read ISO9660 primary
> +volume descriptor from ~s" device)))))

‘format’ misses an argument.

I hadn’t noticed earlier, but we should use:

  (bytevector-u8-ref sblock 0)

instead of ‘array-ref’ (the array API is not appropriate in this
context; in fact it’s rarely appropriate :-)).

Also make sure to indent the ‘if’ arms properly.

OK with these changes, thanks!

Ludo’.