oe-selftest: devtool: add a proper test to see if tap devices exist

Check up front in test_devtool_deploy_target whether the tap devices
exist and skip if not. If we don't do this we get a significantly less
comprehensible error via pexpect.

Signed-off-by: Paul Eggleton <paul.eggleton@linux.intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

1 files changed, 10 insertions, 0 deletions

diff --git a/meta/lib/oeqa/selftest/devtool.py b/meta/lib/oeqa/selftest/devtool.py
index 2344fac5d8..1d16113343 100644
--- a/meta/lib/oeqa/selftest/devtool.py
+++ b/meta/lib/oeqa/selftest/devtool.py
@@ -587,6 +587,16 @@ class DevtoolTests(oeSelfTest):
             self.skipTest('This test only works with qemu machines')
         if not os.path.exists('/etc/runqemu-nosudo'):
             self.skipTest('You must set up tap devices with scripts/runqemu-gen-tapdevs before running this test')
+        result = runCmd('PATH="$PATH:/sbin:/usr/sbin" ip tuntap show', ignore_status=True)
+        if result.status != 0:
+            result = runCmd('PATH="$PATH:/sbin:/usr/sbin" ifconfig -a', ignore_status=True)
+            if result.status != 0:
+                self.skipTest('Failed to determine if tap devices exist with ifconfig or ip: %s' % result.output)
+        for line in result.output.splitlines():
+            if line.startswith('tap'):
+                break
+        else:
+            self.skipTest('No tap devices found - you must set up tap devices with scripts/runqemu-gen-tapdevs before running this test')
         workspacedir = os.path.join(self.builddir, 'workspace')
         self.assertTrue(not os.path.exists(workspacedir), 'This test cannot be run with a workspace directory under the build directory')
         import pexpect