test that the file descriptor ZGetFD returns is actually a socket

2 files changed, 31 insertions, 2 deletions

diff --git a/lib/zephyr_tests.py b/lib/zephyr_tests.py
index 043ed2b..5855238 100755
--- a/lib/zephyr_tests.py
+++ b/lib/zephyr_tests.py
@@ -593,6 +593,26 @@ def find_buildpath():
 
     return os.path.join(opts.builddir, "lib")
 
+def getsockname(fd):
+    """wrapped C lib getsocketname (works on raw fd)"""
+    libc = ctypes.cdll.LoadLibrary(ctypes.util.find_library("c"))
+
+    call_getsockname = libc.getsockname
+    call_getsockname.argtypes = [
+        c_int,                 # int s
+        POINTER(sockaddr),     # struct sockaddr *name
+        POINTER(c_int),        # socklen_t *namelen
+        ]
+    name = sockaddr(0)
+    namelen = c_int(sizeof(name))
+    ret = call_getsockname(fd, name, namelen)
+    if ret == 0:
+        return name
+    # we can't get at errno until python 2.6...
+    print ret
+    raise EnvironmentError("getsockname failed")
+
+
 if __name__ == "__main__":
     tester = ZephyrTestSuite(builddir=find_buildpath())
     tester.setup()
diff --git a/lib/zephyr_tests.txt b/lib/zephyr_tests.txt
index 906399a..a30cb88 100644
--- a/lib/zephyr_tests.txt
+++ b/lib/zephyr_tests.txt
@@ -176,6 +176,17 @@ Trivial test of ZOpenPort and ZClosePort:
    >>> st = _z.ZOpenPort(port)
    >>> assert st == 0
    >>> assert _z.ZGetFD() != -1
+   >>> zsock = zephyr_tests.getsockname(_z.ZGetFD())
+   >>> assert zsock
+   >>> from socket import AF_INET
+   >>> assert zsock.sa_family.value == AF_INET, zsock.sa_family
+
+(Here we're actually using getsockname as an "is that file descriptor
+ a socket" test; the wrapper is weak in that it can't check for
+ ENOTSOCK without requiring Python 2.6, so it just throws an exception
+ on any return of -1.  If ctypes.cast worked on sockaddr, we could
+ also cast it to sockaddr_in and look at the address and port...)
+
    >>> assert port != 0
    >>> zephyr_tests.ctypes_pprint(_z.ZGetDestAddr())
    ... # doctest: +ELLIPSIS
@@ -184,8 +195,6 @@ Trivial test of ZOpenPort and ZClosePort:
    sin_addr 127.0.0.1
    sin_zero [ignored]
 
-TODO: consider checking that ZGetFD is returning a socket on that port.
-
    >>> assert _z.ZClosePort() == 0
    >>> assert _z.ZGetFD() == -1