Broke BSD ifconfig parser into chunks for subclassing

This allows minor changes to be handled by adding a new
parse line function to the subclass

setup

@@ -860,44 +860,87 @@ class GenericBsdIfconfigNetwork(Network):
             if line:
                 words = line.split()
                 if re.match('^\S', line) and len(words) > 3:
+                    current_if = self.parse_interface_line(words)
+                    interfaces[ current_if['device'] ] = current_if
+                elif words[0].startswith('options='):
+                    self.parse_options_line(words, current_if, ips)
+                elif words[0] == 'nd6':
+                    self.parse_nd6_line(words, current_if, ips)
+                elif words[0] == 'ether':
+                    self.parse_ether_line(words, current_if, ips)
+                elif words[0] == 'media:':
+                    self.parse_media_line(words, current_if, ips)
+                elif words[0] == 'status:':
+                    self.parse_status_line(words, current_if, ips)
+                elif words[0] == 'lladdr':
+                    self.parse_lladdr_line(words, current_if, ips)
+                elif words[0] == 'inet':
+                    self.parse_inet_line(words, current_if, ips)
+                elif words[0] == 'inet6':
+                    self.parse_inet6_line(words, current_if, ips)
+                else:
+                    self.parse_unknown_line(words, current_if, ips)
+
+        return interfaces, ips
+
+    def parse_interface_line(self, words):
         device = words[0][0:-1]
         current_if = {'device': device, 'ipv4': [], 'ipv6': [], 'type': 'unknown'}
-                    interfaces[device] = current_if
         current_if['flags'] = self.get_options(words[1])
         current_if['mtu'] = words[3]
         current_if['macaddress'] = 'unknown'    # will be overwritten later
-                elif words[0].startswith('options='):
+        return current_if
+
+    def parse_options_line(self, words, current_if, ips):
         # Mac has options like this...
         current_if['options'] = self.get_options(words[0])
-                elif words[0] == 'nd6':
+
+    def parse_nd6_line(self, words, current_if, ips):
         # FreBSD has options like this...
         current_if['options'] = self.get_options(words[1])
-                elif words[0] == 'ether':
+
+    def parse_ether_line(self, words, current_if, ips):
         current_if['macaddress'] = words[1]
-                elif words[0] == 'media:':
+
+    def parse_media_line(self, words, current_if, ips):
         # not sure if this is useful - we also drop information
         current_if['media'] = words[1]
-                elif words[0] == 'status:':
+        if len(words) > 2:
+            current_if['media_select'] = words[2]
+        if len(words) > 3:
+            current_if['media_type'] = words[3][1:]
+        if len(words) > 4:
+            current_if['media_options'] = self.get_options(words[4])
+
+    def parse_status_line(self, words, current_if, ips):
         current_if['status'] = words[1]
-                elif words[0] == 'lladdr':
+
+    def parse_lladdr_line(self, words, current_if, ips):
         current_if['lladdr'] = words[1]
-                elif words[0] == 'inet':
+
+    def parse_inet_line(self, words, current_if, ips):
         address = {'address': words[1]}
+        # deal with hex netmask
         if words[3].startswith('0x'):
             address['netmask'] = socket.inet_ntoa(struct.pack('!L', int(words[3], base=16)))
         else:
+            # otherwise assume this is a dotted quad
             address['netmask'] = words[3]
-                    if len(words) > 5:
-                        address['broadcast'] = words[5]
         # calculate the network
         address_bin = struct.unpack('!L', socket.inet_aton(address['address']))[0]
         netmask_bin = struct.unpack('!L', socket.inet_aton(address['netmask']))[0]
         address['network'] = socket.inet_ntoa(struct.pack('!L', address_bin & netmask_bin))
+        # broadcast may be given or we need to calculate
+        if len(words) > 5:
+            address['broadcast'] = words[5]
+        else:
+            address['broadcast'] = socket.inet_ntoa(struct.pack('!L', address_bin | (~netmask_bin & 0xffffffff)))
         # add to our list of addresses
         if not words[1].startswith('127.'):
             ips['all_ipv4_addresses'].append(address['address'])
         current_if['ipv4'].append(address)
-                elif words[0] == 'inet6':
+
+    def parse_inet6_line(self, words, current_if, ips):
         address = {'address': words[1]}
         if (len(words) >= 4) and (words[2] == 'prefixlen'):
             address['prefix'] = words[3]
@@ -906,11 +949,15 @@ class GenericBsdIfconfigNetwork(Network):
         if not address['address'] == '::1' and not address['address'] == 'fe80::1%lo0':
             ips['all_ipv6_addresses'].append(address['address'])
         current_if['ipv6'].append(address)
-        return interfaces, ips
+
+    def parse_unknown_line(self, words, current_if, ips):
+        # we are going to ignore unknown lines here - this may be
+        # a bad idea - but you can override it in your subclass
+        pass
 
     def get_options(self, option_string):
         start = option_string.find('<') + 1
-        end = option_string.rfind('>') - 1
+        end = option_string.rfind('>')
         if (start > 0) and (end > 0) and (end > start + 1):
             option_csv = option_string[start:end]
             return option_csv.split(',')
@@ -936,6 +983,17 @@ class DarwinNetwork(GenericBsdIfconfigNetwork, Network):
     """
     platform = 'Darwin'
 
+    # media line is different to the default FreeBSD one
+    def parse_media_line(self, words, current_if, ips):
+        # not sure if this is useful - we also drop information
+        current_if['media'] = 'Unknown' # Mac does not give us this
+        current_if['media_select'] = words[1]
+        if len(words) > 2:
+            current_if['media_type'] = words[2][1:]
+        if len(words) > 3:
+            current_if['media_options'] = self.get_options(words[3])
+
+
 class FreeBSDNetwork(GenericBsdIfconfigNetwork, Network):
     """
     This is the FreeBSD Network Class.