gh-126400: Add TCP socket timeout to SysLogHandler to prevent blocking (GH-126716)

Co-authored-by: Vinay Sajip <vinay_sajip@yahoo.co.uk>

Lib/logging/handlers.py

@@ -855,7 +855,7 @@ class SysLogHandler(logging.Handler):
     }
 
     def __init__(self, address=('localhost', SYSLOG_UDP_PORT),
-                 facility=LOG_USER, socktype=None):
+                 facility=LOG_USER, socktype=None, timeout=None):
         """
         Initialize a handler.
 
@@ -872,6 +872,7 @@ class SysLogHandler(logging.Handler):
         self.address = address
         self.facility = facility
         self.socktype = socktype
+        self.timeout = timeout
         self.socket = None
         self.createSocket()
 
@@ -933,6 +934,8 @@ class SysLogHandler(logging.Handler):
                 err = sock = None
                 try:
                     sock = socket.socket(af, socktype, proto)
+                    if self.timeout:
+                        sock.settimeout(self.timeout)
                     if socktype == socket.SOCK_STREAM:
                         sock.connect(sa)
                     break