Port gevent vfd to win64

Since long on win64 is 32-bit it cannot hold all possible
SOCKET handle values, making it theoretically possible to
get an exception "OverflowError: Python int too large to
convert to C long" if socket handles become too big. Now
on win64 it properly uses PY_LONG_LONG.

gevent/core.ppyx

@@ -453,8 +453,13 @@ cdef public class loop [object PyGeventLoopObject, type PyGeventLoop_Type]:
             CHECK_LOOP3(self)
             return libev.ev_pending_count(self._ptr)
 
+#ifdef _WIN32
+    def io(self, libev.vfd_socket_t fd, int events, ref=True, priority=None):
+        return io(self, fd, events, ref, priority)
+#else
     def io(self, int fd, int events, ref=True, priority=None):
         return io(self, fd, events, ref, priority)
+#endif
 
     def timer(self, double after, double repeat=0.0, ref=True, priority=None):
         return timer(self, after, repeat, ref, priority)
@@ -785,7 +790,7 @@ cdef public class io(watcher) [object PyGeventIOObject, type PyGeventIO_Type]:
 
 #ifdef _WIN32
 
-    def __init__(self, loop loop, long fd, int events, ref=True, priority=None):
+    def __init__(self, loop loop, libev.vfd_socket_t fd, int events, ref=True, priority=None):
         if events & ~(libev.EV__IOFDSET | libev.EV_READ | libev.EV_WRITE):
             raise ValueError('illegal event mask: %r' % events)
         cdef int vfd = libev.vfd_open(fd)

gevent/libev.pxd

 cdef extern from "libev_vfd.h":
+#ifdef _WIN32
+#ifdef _WIN64
+    ctypedef long long vfd_socket_t
+#else
+    ctypedef long vfd_socket_t
+#endif
+#else
+    ctypedef int vfd_socket_t
+#endif
     long vfd_get(int)
     int vfd_open(long) except -1
     void vfd_free(int)

gevent/libev_vfd.h

 #ifdef _WIN32
+#ifdef _WIN64
+typedef PY_LONG_LONG vfd_socket_t;
+#define vfd_socket_object PyLong_FromLongLong
+#else
+typedef long vfd_socket_t;
+#define vfd_socket_object PyInt_FromLong
+#endif
 #ifdef LIBEV_EMBED
 /*
  * If libev on win32 is embedded, then we can use an
@@ -13,7 +20,7 @@
 
 typedef struct vfd_entry_t
 {
-	long handle; /* OS handle, i.e. SOCKET */
+	vfd_socket_t handle; /* OS handle, i.e. SOCKET */
 	int count; /* Reference count, 0 if free */
 	int next; /* Next free fd, -1 if last */
 } vfd_entry;
@@ -58,7 +65,7 @@ static CRITICAL_SECTION* vfd_make_lock()
  * Given a virtual fd returns an OS handle or -1
  * This function is speed critical, so it cannot use GIL
  */
-static long vfd_get(int fd)
+static vfd_socket_t vfd_get(int fd)
 {
 	int handle = -1;
 	VFD_LOCK_ENTER;
@@ -74,7 +81,7 @@ static long vfd_get(int fd)
  * Given an OS handle finds or allocates a virtual fd
  * Returns -1 on failure and sets Python exception if pyexc is non-zero
  */
-static int vfd_open_(long handle, int pyexc)
+static int vfd_open_(vfd_socket_t handle, int pyexc)
 {
 	VFD_GIL_DECLARE;
 	int fd = -1;
@@ -87,7 +94,13 @@ static int vfd_open_(long handle, int pyexc)
 	}
 	if (ioctlsocket(handle, FIONREAD, &arg) != 0) {
 		if (pyexc)
-			PyErr_Format(PyExc_IOError, "%ld is not a socket (files are not supported)", handle);
+			PyErr_Format(PyExc_IOError,
+#ifdef _WIN64
+				"%lld is not a socket (files are not supported)",
+#else
+				"%ld is not a socket (files are not supported)",
+#endif
+				handle);
 		goto done;
 	}
 	if (vfd_map == NULL) {
@@ -95,7 +108,7 @@ static int vfd_open_(long handle, int pyexc)
 		if (vfd_map == NULL)
 			goto done;
 	}
-	key = PyLong_FromLong(handle);
+	key = vfd_socket_object(handle);
 	/* check if it's already in the dict */
 	value = PyDict_GetItem(vfd_map, key);
 	if (value != NULL) {
@@ -168,14 +181,14 @@ static void vfd_free_(int fd, int needclose)
 		goto done; /* free entry, ignore */
 	if (!--vfd_entries[fd].count) {
 		/* fd has just been freed */
-		long handle = vfd_entries[fd].handle;
+		vfd_socket_t handle = vfd_entries[fd].handle;
 		vfd_entries[fd].handle = -1;
 		vfd_entries[fd].next = vfd_next;
 		vfd_next = fd;
 		if (needclose)
 			closesocket(handle);
 		/* vfd_map is assumed to be != NULL */
-		key = PyLong_FromLong(handle);
+		key = vfd_socket_object(handle);
 		PyDict_DelItem(vfd_map, key);
 		Py_DECREF(key);
 	}
@@ -203,6 +216,7 @@ done:
 /*
  * On non-win32 platforms vfd_* are noop macros
  */
+typedef int vfd_socket_t;
 #define vfd_get(fd) (fd)
 #define vfd_open(fd) ((int)(fd))
 #define vfd_free(fd)