bug#27563: [PATCH] gnu: ghostscript: Don't write document UUID; use "" as instance UUID.

[Ludovic Courtès]

Danny Milosavljevic <address@hidden> skribis:

> * gnu/packages/patches/ghostscript-no-header-uuid.patch: New file.
> * gnu/local.mk (dist_patch_DATA): Add it.
> * gnu/packages/ghostscript.scm (ghostscript)[source]: Use it.

[...]

> --- /dev/null
> +++ b/gnu/packages/patches/ghostscript-no-header-uuid.patch
> @@ -0,0 +1,28 @@
> +--- a/devices/vector/gdevpdfe.c      2017-07-06 10:22:28.131889858 +0200
> ++++ b/devices/vector/gdevpdfe.c      2017-07-06 10:24:25.137842222 +0200

Please add a comment at the top of the patch to explain what it does and
what its upstream status is or if there were discussions around it.

> +             pdf_xml_tag_open_beg(s, "rdf:Description");
> +-            pdf_xml_attribute_name(s, "rdf:about");
> +-            pdf_xml_attribute_value(s, instance_uuid);
> +-            pdf_xml_attribute_name(s, "xmlns:xapMM");
> +-            pdf_xml_attribute_value(s, "http://ns.adobe.com/xap/1.0/mm/";);
> +-            pdf_xml_attribute_name(s, "xapMM:DocumentID");
> +-            pdf_xml_attribute_value(s, document_uuid);
> +-            pdf_xml_tag_end_empty(s);
> +-            pdf_xml_newline(s);
> +-
> +-            pdf_xml_tag_open_beg(s, "rdf:Description");

What’s the impact of simply removing all of this from generated PDF
files?  Should we instead make it optional?  For instance, we could
introduce a new environment variable, say “GHOSTSCRIPT_PDF_UUID”, and
use that as the document UUID when it’s defined.  In our build
environments, we’d always set GHOSTSCRIPT_PDF_UUID to a known value to
ensure determinism.

WDYT?

Also, what does Debian do?  :-)

Thank you for working on it!

Ludo’.