The Annoyance Filter.pdf - Fourmilab

§214 ANNOYANCE-FILTER POP3 PROXY SERVER CLASS DEFINITION 177
214. We’re all done. Having relayed the reply to the “quit” command, or having something go blooie
in the processing loop, we close the client and server sockets and get ready to bail out from servicing
this connection.
〈 Close the connection to the client and server 214 〉 ≡
close (clientSocket );
close (serverSocket );
if (verbose ) {
cerr ≪ "Closing␣POP3␣connection␣from␣" ≪ inet ntoa (from .sin addr ) ≪ endl ;
}
This code is used in section 200.
215. If you simply wish to run a POP3 proxy server until the end of time, you can invoke this method
which puts it all together. We return only if something blows up, after which the caller is well-advised
to destroy the POP3Proxy object and try again.
〈 Class implementations 11 〉 +≡
#ifdef POP3_PROXY_SERVER
bool POP3Proxy ::operateProxyServer (int maxBacklog )
{
if (acceptConnections (maxBacklog )) {
while (serviceConnection ( )) ;
}
return false ;
}
#endif
216. Various alarums and diversions will result in our receiving a SIGPIPE signal whilst acting as a
POP3 server. These may be safely ignored, as the following function does.
〈 Declare signal handler function for broken pipes 216 〉 ≡
static RETSIGTYPEabsentPlumber (int)
{
if (popProxyTrace ) {
cerr ≪ "POP3:␣Caught␣SIGPIPE−−continuing." ≪ endl ;
}
signal (SIGPIPE, absentPlumber ); /∗ Reset signal just in case ∗/
}
This code is used in section 194.