[PATCH v2 13/21] avocado/tasst: Add helper for getting MTU of a network interface

[David Gibson <david@gibson.dropbear.id.au>]

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
---
 avocado/tasst/meta/veth.py | 4 ++++
 avocado/tasst/site.py      | 9 +++++++++
 2 files changed, 13 insertions(+)

diff --git a/avocado/tasst/meta/veth.py b/avocado/tasst/meta/veth.py
index 48ef88b..afca192 100644
--- a/avocado/tasst/meta/veth.py
+++ b/avocado/tasst/meta/veth.py
@@ -41,3 +41,7 @@ class VethTasst(Tasst):
     def test_ifs(self):
         self.assertCountEqual(self.ns1.ifs(), ['lo', 'veth1'])
         self.assertCountEqual(self.ns2.ifs(), ['lo', 'veth2'])
+
+    def test_mtu(self):
+        self.assertEquals(self.ns1.mtu('veth1'), 1500)
+        self.assertEquals(self.ns2.mtu('veth2'), 1500)
diff --git a/avocado/tasst/site.py b/avocado/tasst/site.py
index 5a63b76..00b86aa 100644
--- a/avocado/tasst/site.py
+++ b/avocado/tasst/site.py
@@ -64,6 +64,11 @@ class Site:
         self.require_cmds('ip')
         self.fg('ip link set {} up'.format(ifname), sudo=True)
 
+    def mtu(self, ifname):
+        self.require_cmds('ip')
+        (info,) = json.loads(self.output('ip -j link show {}'.format(ifname)))
+        return info['mtu']
+
     def addrinfos(self, ifname, **filter):
         self.require_cmds('ip')
         info = json.loads(self.output('ip -j addr show {}'.format(ifname)))
@@ -134,6 +139,10 @@ class BaseSiteTasst(Tasst):
                     for a in ['127.0.0.1/8', '::1/128']]
         self.assertCountEqual(site.addrs('lo'), expected)
 
+    def test_lo_mtu(self):
+        site = self.get_subsetup(BaseSiteTasst)
+        self.assertEqual(site.mtu('lo'), 65536)
+
 
 # Represents the host on which the tests are running, as opposed to
 # some simulated host created by the tests
-- 
@@ -64,6 +64,11 @@ class Site:
         self.require_cmds('ip')
         self.fg('ip link set {} up'.format(ifname), sudo=True)
 
+    def mtu(self, ifname):
+        self.require_cmds('ip')
+        (info,) = json.loads(self.output('ip -j link show {}'.format(ifname)))
+        return info['mtu']
+
     def addrinfos(self, ifname, **filter):
         self.require_cmds('ip')
         info = json.loads(self.output('ip -j addr show {}'.format(ifname)))
@@ -134,6 +139,10 @@ class BaseSiteTasst(Tasst):
                     for a in ['127.0.0.1/8', '::1/128']]
         self.assertCountEqual(site.addrs('lo'), expected)
 
+    def test_lo_mtu(self):
+        site = self.get_subsetup(BaseSiteTasst)
+        self.assertEqual(site.mtu('lo'), 65536)
+
 
 # Represents the host on which the tests are running, as opposed to
 # some simulated host created by the tests
-- 
2.40.1