some stuff moved

src/netns/interface.py

+# vim:ts=4:sw=4:et:ai:sts=4
+
+import re, socket
+
+__all__ = ['interface', 'address', 'ipv6address', 'ipv4address']
+
+# helpers
+
+def _any_to_bool(any):
+    if isinstance(any, bool):
+        return any
+    if isinstance(any, int):
+        return any != 0
+    if isinstance(any, str):
+        if any.isdigit():
+            return int(any) != 0
+        if any.lower() == "true":
+            return True
+        if any.lower() == "false":
+            return False
+        return any != ""
+    return bool(any)
+
+def _make_getter(attr, conv = lambda x: x):
+    def getter(self):
+        return conv(getattr(self, attr))
+    return getter
+def _make_setter(attr, conv = lambda x: x):
+    def setter(self, value):
+        if value == None:
+            setattr(self, attr, None)
+        else:
+            setattr(self, attr, conv(value))
+    return setter
+
+class interface(object):
+    @classmethod
+    def parse_ip(cls, line):
+        match = re.search(r'^(\d+): (\S+): <(\S+)> mtu (\d+) qdisc \S+' +
+                r'.*link/\S+ ([0-9a-f:]+) brd ([0-9a-f:]+)', line)
+        flags = match.group(3).split(",")
+        return cls(
+                index   = match.group(1),
+                name    = match.group(2),
+                up      = "UP" in flags,
+                mtu     = match.group(4),
+                lladdr  = match.group(5),
+                arp     = not ("NOARP" in flags),
+                broadcast = match.group(6),
+                multicast = "MULTICAST" in flags)
+
+    index = property(_make_getter("_index"), _make_setter("_index", int))
+    up = property(_make_getter("_up"), _make_setter("_up", _any_to_bool))
+    mtu = property(_make_getter("_mtu"), _make_setter("_mtu", int))
+    arp = property(_make_getter("_arp"), _make_setter("_arp", _any_to_bool))
+    multicast = property(_make_getter("_mc"), _make_setter("_mc", _any_to_bool))
+
+    def __init__(self, index = None, name = None, up = None, mtu = None,
+            lladdr = None, broadcast = None, multicast = None, arp = None):
+        self.index = index
+        self.name = name
+        self.up = up
+        self.mtu = mtu
+        self.lladdr = lladdr
+        self.broadcast = broadcast
+        self.multicast = multicast
+        self.arp = arp
+
+    def __repr__(self):
+        s = "%s.%s(index = %s, name = %s, up = %s, mtu = %s, lladdr = %s, "
+        s += "broadcast = %s, multicast = %s, arp = %s)"
+        return s % (self.__module__, self.__class__.__name__,
+                self.index.__repr__(), self.name.__repr__(),
+                self.up.__repr__(), self.mtu.__repr__(),
+                self.lladdr.__repr__(), self.broadcast.__repr__(),
+                self.multicast.__repr__(), self.arp.__repr__())
+
+    def __sub__(self, o):
+        """Compare attributes and return a new object with just the attributes
+        that differ set (with the value they have in the first operand). The
+        index remains equal to the first operand."""
+        name = None if self.name == o.name else self.name
+        up = None if self.up == o.up else self.up
+        mtu = None if self.mtu == o.mtu else self.mtu
+        lladdr = None if self.lladdr == o.lladdr else self.lladdr
+        broadcast = None if self.broadcast == o.broadcast else self.broadcast
+        multicast = None if self.multicast == o.multicast else self.multicast
+        arp = None if self.arp == o.arp else self.arp
+        return self.__class__(self.index, name, up, mtu, lladdr, broadcast,
+                multicast, arp)
+
+class address(object):
+    @classmethod
+    def parse_ip(cls, line):
+        match = re.search(r'^inet ([0-9.]+)/(\d+)(?: brd ([0-9.]+))?', line)
+        if match != None:
+            return ipv4address(
+                address     = match.group(1),
+                prefix_len  = match.group(2),
+                broadcast   = match.group(3))
+
+        match = re.search(r'^inet6 ([0-9a-f:]+)/(\d+)', line)
+        if match != None:
+            return ipv6address(
+                address     = match.group(1),
+                prefix_len  = match.group(2))
+
+        raise RuntimeError("Problems parsing ip command output")
+
+    # broadcast is not taken into account for differentiating addresses
+    def __eq__(self, o):
+        if not isinstance(o, address):
+            return False
+        return (self.family == o.family and self.address == o.address and
+                self.prefix_len == o.prefix_len)
+
+    def __hash__(self):
+        h = (self.address.__hash__() ^ self.prefix_len.__hash__() ^
+                self.family.__hash__())
+        return h
+ 
+class ipv4address(address):
+    def __init__(self, address, prefix_len, broadcast):
+        self.address = address
+        self.prefix_len = int(prefix_len)
+        self.broadcast = broadcast
+        self.family = socket.AF_INET
+
+    def __repr__(self):
+        s = "%s.%s(address = %s, prefix_len = %d, broadcast = %s)"
+        return s % (self.__module__, self.__class__.__name__,
+                self.address.__repr__(), self.prefix_len,
+                self.broadcast.__repr__())
+
+class ipv6address(address):
+    def __init__(self, address, prefix_len):
+        self.address = address
+        self.prefix_len = int(prefix_len)
+        self.family = socket.AF_INET6
+
+    def __repr__(self):
+        s = "%s.%s(address = %s, prefix_len = %d)"
+        return s % (self.__module__, self.__class__.__name__,
+                self.address.__repr__(), self.prefix_len)
+