added ctypes dependency for old Pythons on Windows

2 files changed, 16 insertions, 1 deletions

diff --git a/pysnmp/smi/mibs/TRANSPORT-ADDRESS-MIB.py b/pysnmp/smi/mibs/TRANSPORT-ADDRESS-MIB.py
index 992a9496..6f4e6bb8 100644
--- a/pysnmp/smi/mibs/TRANSPORT-ADDRESS-MIB.py
+++ b/pysnmp/smi/mibs/TRANSPORT-ADDRESS-MIB.py
@@ -2,6 +2,7 @@
 # by libsmi2pysnmp-0.1.3 at Tue Apr  3 16:58:37 2012,
 # Python version sys.version_info(major=2, minor=7, micro=2, releaselevel='final', serial=0)
 
+from pysnmp.error import PySnmpError
 from socket import AF_INET, error, has_ipv6
 
 try:
@@ -19,7 +20,10 @@ except ImportError:
         inet_pton = lambda x,y: inet_aton(y)
         has_ipv6 = False
     elif has_ipv6:
-        import ctypes
+        try:
+            import ctypes
+        except ImportError:
+            raise PySnmpError('Need ctypes module to handle IPv6 addresses')
  
         class sockaddr(ctypes.Structure):
             _fields_ = [("sa_family", ctypes.c_short),
diff --git a/setup.py b/setup.py
index a6a10814..82bae33d 100644
--- a/setup.py
+++ b/setup.py
@@ -52,6 +52,8 @@ try:
         }
     if sys.platform.lower()[:3] != 'win':
         params['install_requires'].append('pycrypto>=2.4.1')
+    elif sys.version_info[:2] < (2, 5):
+        params['install_requires'].append('ctypes')
 
 except ImportError:
     for arg in sys.argv:
@@ -64,6 +66,15 @@ except ImportError:
         params['requires'] = [ 'pyasn1(>=0.1.2)' ]
         if sys.platform.lower()[:3] != 'win':
             params['requires'].append('pycrypto(>=2.4.1)')
+    elif sys.platform.lower()[:3] == 'win':
+        try:
+            import ctypes
+        except ImportError:
+            sys.stderr.write("""WARNING! WARNING! WARNING!
+Handling IPv6 addresses requires the ctypes module. Please install it on
+your system if you need PySNMP supporting IPv6 addressing:
+http://downloads.sourceforge.net/project/ctypes/ctypes/1.0.2/ctypes-1.0.2.tar.gz
+""")
 
 if sys.platform.lower()[:3] == 'win':
     try: