tests: kill for windows in killdaemons.py checks return values

The return values of the windll calls are checked and when an error is
indicated, it is raised. The handle is still closed properly.

tests/killdaemons.py

@@ -1,54 +1,71 b''
 #!/usr/bin/env python
 
 import os, sys, time, errno, signal
 
 if os.name =='nt':
     import ctypes
+
+    def _check(ret, expectederr=None):
+        if ret == 0:
+            winerrno = ctypes.GetLastError()
+            if winerrno == expectederr:
+                return True
+            raise ctypes.WinError(winerrno)
+
     def kill(pid, logfn, tryhard=True):
         logfn('# Killing daemon process %d' % pid)
         PROCESS_TERMINATE = 1
         handle = ctypes.windll.kernel32.OpenProcess(
                 PROCESS_TERMINATE, False, pid)
-        ctypes.windll.kernel32.TerminateProcess(handle, -1)
-        ctypes.windll.kernel32.CloseHandle(handle)
+        if handle == 0:
+            # TODO: call _check(0, expected) to check if "process not found"
+            return # process not found, already finished
+        try:
+            _check(ctypes.windll.kernel32.TerminateProcess(handle, -1), 5)
+            #      windows error 5 when process does not exist or no access TODO
+        except: #re-raises
+            ctypes.windll.kernel32.CloseHandle(handle) # no _check, keep error
+            raise
+        _check(ctypes.windll.kernel32.CloseHandle(handle))
+
 else:
     def kill(pid, logfn, tryhard=True):
         try:
             os.kill(pid, 0)
             logfn('# Killing daemon process %d' % pid)
             os.kill(pid, signal.SIGTERM)
             if tryhard:
                 for i in range(10):
                     time.sleep(0.05)
                     os.kill(pid, 0)
             else:
                 time.sleep(0.1)
                 os.kill(pid, 0)
             logfn('# Daemon process %d is stuck - really killing it' % pid)
             os.kill(pid, signal.SIGKILL)
         except OSError, err:
             if err.errno != errno.ESRCH:
                 raise
 
 def killdaemons(pidfile, tryhard=True, remove=False, logfn=None):
     if not logfn:
         logfn = lambda s: s
     # Kill off any leftover daemon processes
     try:
         fp = open(pidfile)
         for line in fp:
             try:
                 pid = int(line)
             except ValueError:
                 continue
             kill(pid, logfn, tryhard)
         fp.close()
         if remove:
             os.unlink(pidfile)
     except IOError:
         pass
 
 if __name__ == '__main__':
     path, = sys.argv[1:]
     killdaemons(path)