[ovs-git] [ovn-org/ovn] a2b3b3: configure: Save OVSDIR as an absolute path.

[Mark Michelson]

  Branch: refs/heads/master
  Home:   https://github.com/ovn-org/ovn
  Commit: a2b3b363d1ef7fe78f0348dfd6ed33b0fe653c03
      https://github.com/ovn-org/ovn/commit/a2b3b363d1ef7fe78f0348dfd6ed33b0fe653c03
  Author: Mark Michelson <mmichels at redhat.com>
  Date:   2021-04-12 (Mon, 12 Apr 2021)

  Changed paths:
    M acinclude.m4

  Log Message:
  -----------
  configure: Save OVSDIR as an absolute path.

Lately, `make check` runs have been failing. When "--with-ovs-source"
is not specified at configure time, the configure script automatically
sets the location to "$srcdir/ovs". This location is passed along the
chain and eventually added to AUTOTEST_PATH when running the tests.

$srcdir is a relative path name, which is fine when building the code.
This falls apart, though, when tests are run. Tests are not run from
the build directory, but instead from the tests/ directory. Therefore,
the relative path to ovs/ is different. This causes most tests to fail
since files are not in the expected location.

The fix is to set OVSDIR to an absolute path instead. Autoconf documents
an $abs_srcdir variable, but this is not set until after configure
checks are run. It is meant to be used by Makefiles. Therefore, we use
the trick of cd-ing to the directory and calling pwd to expand it to the
absolute path.

Signed-off-by: Mark Michelson <mmichels at redhat.com>
Acked-by: Dumitru Ceara <dceara at redhat.com>