utils.network: Use all local addresses in is_port_free

When binding to 0.0.0.0 all local addresses are used and these are
not covered by "localhost" binding. Let's use "" which makes sure we can
bind on all local addresses (including eg. 192.168.122.1).
Signed-off-by: NLukáš Doktor <ldoktor@redhat.com>

avocado/utils/network.py

@@ -50,7 +50,7 @@ def is_port_free(port, address):
                 try:
                     s = socket.socket(family, protocol)
                     if address == "localhost":
-                        s.bind((address, port))
+                        s.bind(("", port))
                     else:
                         s.connect((address, port))
                         return False

python-avocado.spec

@@ -128,6 +128,7 @@ BuildRequires: libcdio
 BuildRequires: libvirt-python
 BuildRequires: perl-Test-Harness
 BuildRequires: psmisc
+BuildRequires: python2-netifaces
 %if 0%{?rhel}
 BuildRequires: PyYAML
 %else
@@ -136,6 +137,7 @@ BuildRequires: python2-yaml
 %if %{with_python3}
 BuildRequires: python3-libvirt
 BuildRequires: python3-yaml
+BuildRequires: python3-netifaces
 %endif
 %endif
 

requirements-selftests.txt

@@ -34,3 +34,6 @@ lxml==4.2.4
 # in make develop. The proper solution would be migrate
 # our make develop process to use pip
 libvirt-python==4.6.0
+
+# For avocado.utils.network selftests
+netifaces

selftests/unit/test_utils_network.py

+import netifaces
 import socket
 import unittest
 
@@ -34,17 +35,29 @@ class PortTrackerTest(unittest.TestCase):
         self.assertNotIn(22, tracker.retained_ports)
 
 
+def get_all_local_addrs():
+    """
+    Returns all ipv4/ipv6 addresses that are associated with this machine
+    """
+    ipv4_addrs = []
+    ipv6_addrs = []
+    for interface in netifaces.interfaces():
+        ifaddresses = netifaces.ifaddresses(interface)
+        ipv4_addrs += [_['addr']
+                       for _ in ifaddresses.get(netifaces.AF_INET, [])]
+        ipv6_addrs += [_['addr']
+                       for _ in ifaddresses.get(netifaces.AF_INET6, [])]
+    return ipv4_addrs, ipv6_addrs
+
+
 class FreePort(unittest.TestCase):
 
     def test_is_port_free(self):
         port = network.find_free_port(sequent=False)
-        if port is None:
-            # Use this temporarily as in Travis the current implementation
-            # fails to find free port.
-            self.skipTest("No free port")
         self.assertTrue(network.is_port_free(port, "localhost"))
-        ipv4_addrs = ["localhost", "127.0.0.1"]
-        ipv6_addrs = ["localhost", "::1"]
+        local_addrs = get_all_local_addrs()
+        ipv4_addrs = ["localhost", ""] + list(local_addrs[0])
+        ipv6_addrs = ["localhost", ""] + list(local_addrs[1])
         good = []
         bad = []
         skip = []