Issue #11: daemonize after opening listen port.

The listen port should be opened before daemonizing otherwise if
opening the port fails, the user will get no feedback. The only
complication was that the listen socket needs to not be closed as part
of daemonizing.

Thanks to http://github.com/rickr for finding it.

utils/websocket.py

@@ -2,6 +2,8 @@
 
 '''
 Python WebSocket library with support for "wss://" encryption.
+Copyright 2010 Joel Martin
+Licensed under LGPL version 3 (see docs/LICENSE.LGPL-3)
 
 You can make a cert/key with openssl using:
 openssl req -new -x509 -days 365 -nodes -out self.pem -keyout self.pem
@@ -154,7 +156,7 @@ def do_handshake(sock):
     retsock.send(response)
     return retsock
 
-def daemonize():
+def daemonize(keepfd=None):
     os.umask(0)
     os.chdir('/')
     os.setgid(os.getgid())  # relinquish elevations
@@ -175,7 +177,10 @@ def daemonize():
     if maxfd == resource.RLIM_INFINITY: maxfd = 256
     for fd in reversed(range(maxfd)):
         try:
-            os.close(fd)
+            if fd != keepfd:
+                os.close(fd)
+            else:
+                print "Keeping fd: %d" % fd
         except OSError, exc:
             if exc.errno != errno.EBADF: raise
 
@@ -187,12 +192,13 @@ def daemonize():
 
 def start_server():
 
-    if settings['daemon']: daemonize()
-
     lsock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
     lsock.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
     lsock.bind((settings['listen_host'], settings['listen_port']))
     lsock.listen(100)
+
+    if settings['daemon']: daemonize(keepfd=lsock.fileno())
+
     while True:
         try:
             csock = startsock = None