Bug#822633: debsums: No longer bails when there's 'Too many levels of symbolic links', just eats CPU like the cookie monster with cookies

[Unit 193]

Package: debsums
Version: 2.1.2
Severity: important

Dear Maintainer,

This regression is introduced in a01dbf49d7ccfc8d518b5218b0dee51eb5aa3ecc and will occur when a file is a symlink to itself.

To reproduce, try creating /usr/share/doc/libfm-extra4/changelog.Debian.gz -> ../libfm-extra4/changelog.Debian.gz

I have no idea what caused this in the package, but was also reported downstream: https://launchpad.net/bugs/1522563

-- System Information:
Debian Release: stretch/sid
  APT prefers testing-updates
  APT policy: (500, 'testing-updates'), (500, 'testing'), (1, 'experimental')
Architecture: i386 (i686)

Kernel: Linux 4.4.0-1-686-pae (SMP w/2 CPU cores)
Locale: LANG=en_US.UTF-8, LC_CTYPE=en_US.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash
Init: systemd (via /run/systemd/system)

Versions of packages debsums depends on:
ii  dpkg                  1.18.4
ii  libdpkg-perl          1.18.4
ii  libfile-fnmatch-perl  0.02-2+b2
ii  perl                  5.22.1-10
ii  ucf                   3.0036

debsums recommends no packages.

debsums suggests no packages.

-- no debconf information