SF patch 555085 (timeout socket implementation) by Michael Gilfix.

I've made considerable changes to Michael's code, specifically to use
the select() system call directly and to store the timeout as a C
double instead of a Python object; internally, -1.0 (or anything
negative) represents the None from the API.

I'm not 100% sure that all corner cases are covered correctly, so
please keep an eye on this.  Next I'm going to try it Windows before
Tim complains.

No way is this a bugfix candidate. :-)

Lib/test/test_timeout.py

@@ -0,0 +1,136 @@
+#!/home/bernie/src/python23/dist/src/python
+
+import unittest
+
+import time
+import socket
+
+class creationTestCase(unittest.TestCase):
+    """Test Case for socket.gettimeout() and socket.settimeout()"""
+    def setUp(self):
+        self.__s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
+
+    def tearDown(self):
+        self.__s.close()
+
+    def testObjectCreation(self):
+        "Test Socket creation"
+        self.assertEqual(self.__s.gettimeout(), None, 
+            "Timeout socket not default to disable (None)")
+
+    def testFloatReturnValue(self):
+        "Test return value of getter/setter"
+        self.__s.settimeout(7.345)
+        self.assertEqual(self.__s.gettimeout(), 7.345, 
+            "settimeout() and gettimeout() return different result")
+
+        self.__s.settimeout(3)
+        self.assertEqual(self.__s.gettimeout(), 3, 
+            "settimeout() and gettimeout() return different result")
+
+    def testReturnType(self):
+        "Test return type of getter/setter"
+        self.__s.settimeout(1)
+        self.assertEqual(type(self.__s.gettimeout()), type(1.0),
+            "return type of gettimeout() is not FloatType")
+
+        self.__s.settimeout(3.9)
+        self.assertEqual(type(self.__s.gettimeout()), type(1.0),
+            "return type of gettimeout() is not FloatType")
+
+
+class timeoutTestCase(unittest.TestCase):
+    """Test Case for socket.socket() timeout functions"""
+    def setUp(self):
+        self.__s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
+        self.__addr_remote = ('www.google.com', 80)
+        self.__addr_local  = ('127.0.0.1', 25339)
+
+    def tearDown(self):
+        self.__s.close()
+
+    def testConnectTimeout(self):
+        "Test connect() timeout"
+        _timeout = 0.02
+        self.__s.settimeout(_timeout)
+
+        _t1 = time.time()
+        self.failUnlessRaises(socket.error, self.__s.connect,
+                self.__addr_remote)
+        _t2 = time.time()
+
+        _delta = abs(_t1 - _t2)
+        self.assert_(_delta < _timeout + 0.5,
+                "timeout (%f) is 0.5 seconds more than required (%f)"
+                %(_delta, _timeout))
+
+    def testRecvTimeout(self):
+        "Test recv() timeout"
+        _timeout = 0.02
+        self.__s.connect(self.__addr_remote)
+        self.__s.settimeout(_timeout)
+
+        _t1 = time.time()
+        self.failUnlessRaises(socket.error, self.__s.recv, 1024)
+        _t2 = time.time()
+
+        _delta = abs(_t1 - _t2)
+        self.assert_(_delta < _timeout + 0.5,
+                "timeout (%f) is 0.5 seconds more than required (%f)" 
+                %(_delta, _timeout))
+
+    def testAcceptTimeout(self):
+        "Test accept() timeout()"
+        _timeout = 2
+        self.__s.settimeout(_timeout)
+        self.__s.bind(self.__addr_local)
+        self.__s.listen(5)
+
+        _t1 = time.time()
+        self.failUnlessRaises(socket.error, self.__s.accept)
+        _t2 = time.time()
+
+        _delta = abs(_t1 - _t2)
+        self.assert_(_delta < _timeout + 0.5,
+                "timeout (%f) is 0.5 seconds more than required (%f)" 
+                %(_delta, _timeout))
+
+    def testRecvfromTimeout(self):
+        "Test recvfrom() timeout()"
+        _timeout = 2
+        self.__s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
+        self.__s.settimeout(_timeout)
+        self.__s.bind(self.__addr_local)
+
+        _t1 = time.time()
+        self.failUnlessRaises(socket.error, self.__s.recvfrom, 8192)
+        _t2 = time.time()
+
+        _delta = abs(_t1 - _t2)
+        self.assert_(_delta < _timeout + 0.5,
+                "timeout (%f) is 0.5 seconds more than required (%f)" 
+                %(_delta, _timeout))
+
+    def testSend(self):
+        "Test send() timeout"
+        # couldn't figure out how to test it
+        pass
+
+    def testSendto(self):
+        "Test sendto() timeout"
+        # couldn't figure out how to test it
+        pass
+
+    def testSendall(self):
+        "Test sendall() timeout"
+        # couldn't figure out how to test it
+        pass
+
+
+def suite():
+    suite = unittest.TestSuite()
+
+    return suite
+
+if __name__ == "__main__":
+    unittest.main()