Bug#503644: [Pkg-cups-devel] Bug#503644: cups: no IPP printer available any more?

[Till Kamppeter <till.kamppeter@gmail.com>]

Martin Pitt wrote:
> Hi Marc,
>
> Marc Haber [2008-10-27 10:03 +0100]:
> > after upgrading to the experimental CUPS packages, I can no longer
> > configure an IPP printer: The "Device" combo box in the "Add" and
> > "Configure Printer" dialogs only shows "AppSocket/HP JetDirect",
> > "Backend Error Handler", "CUPS-PDF (Virtual PDF Printer)", "HP Fax
> > (HPLIP)", "HP Printer (HPLIP)", "LPT #1", "SCSI Printer" and "Windows
> > Printer via SAMBA".
>
> Is this really any different with the unstable packages? My feeling is
> that this is an upstream decision, and it's like that for my printer,
> too.

My IPP backend on Ubuntu Intrepid (uses the same CUPS package as Debian 
experimental) has the following permissions

till@till-laptop:~/photos$ ll /usr/lib/cups/backend/ipp
-rwxr--r-- 3 root root 28280 2008-11-11 09:55 /usr/lib/cups/backend/ipp
till@till-laptop:~/photos$

Is this intended (to make CUPS run it as root)? "lpinfo -v" does noy 
list "ipp" for me.

> > When I try to print a test page, the printer status says "No %%Pages:
> > comment in header!", but when I look into the actual spool file, it
> > looks like PostScript alright.
>
> That seems to be a bug in one of the filters. Till, any idea how to
> debug this?

First, the newest available CUPS package is needed. The one which comes 
with Intrepid has a bug in pstopdf.


Second, for debugging filter chains you can use the cupsfilter command.


Third, you can temporarily short-circuit pdftopdf via

sudo -s
mv /usr/lib/cups/filter/pdftopdf /usr/lib/cups/filter/pdftopdf.orig
cat > /usr/lib/cups/filter/pdftopdf << EOF
#!/bin/sh
cat \$6
EOF
chmod 755 /usr/lib/cups/filter/pdftopdf
exit

and undo it with

sudo mv /usr/lib/cups/filter/pdftopdf.orig /usr/lib/cups/filter/pdftopdf

Does the problem go away with the short-circuit?


Forth, /usr/lib/cups/filter/pdftoraster is not feature-coomplete. Please 
test with my Ghostscript-based version:

Download this file:

http://www.openprinting.org/download/printing/ghostscript-cups-patches/pdftoraster.c

Install the packages needed to compile it:

sudo apt-get install libcups2-dev libcupsimage2-dev

Compile it:

gcc -lcups -lcupsimage -o pdftoraster pdftoraster.c

Install it:

sudo mv /usr/lib/cups/filter/pdftoraster 
/usr/lib/cups/filter/pdftoraster.orig
sudo cp pdftoraster /usr/lib/cups/filter/
sudo chmod 755 /usr/lib/cups/filter/pdftoraster

Now try to print again. Does it work now?



Fifth, always run CUPS in debug mode ("cupsctl LogLevel=debug") and have 
a look into /var/log/cups/error_log.

   Till