The Annoyance Filter.pdf - Fourmilab

176 POP3 PROXY SERVER CLASS DEFINITION ANNOYANCE-FILTER §213
213. If the server’s reponse included a multi-line reply, relay it to the client. We write it with a single
send unless POP3_MAX_CLIENT_WRITE is defined, in which case we write the reply in chunks of that size;
if you wish to be ultra-conservative, you might define it to be POP_MAX_MESSAGE.
〈 Relay multi-line reply, if any, to the client 213 〉 ≡
if (reply ≠ "") {
if (popProxyTrace ) {
cerr ≪ "POP3:␣Relaying␣" ≪ reply .length ( ) ≪ "␣byte␣multi−line␣reply␣to␣client." ≪
endl ;
}
#ifdef POP3_MAX_CLIENT_WRITE
clientLength = 0;
int rpl = reply .length ( );
while (clientLength < ((int) reply .length ( ))) {
int bcl , pcl ;
bcl = min (rpl , POP3_MAX_CLIENT_WRITE);
#ifdef POP3_TRACE_TRANSFER_DETAIL
if (popProxyTrace ) {
cerr ≪ "POP3:␣Writing␣" ≪ bcl ≪ "␣bytes␣of␣multi−line␣reply␣to␣client." ≪ endl ;
}
#endif
pcl = send (clientSocket , reply .data ( ) + clientLength , bcl , 0);
if (pcl ≠ bcl ) {
if (popProxyTrace ) {
cerr ≪ "POP3:␣Error␣writing␣" ≪ bcl ≪ "␣bytes:␣wrote␣" ≪ pcl ≪ "␣bytes." ≪
endl ;
}
break; /∗ Note that test below will error transfer ∗/
}
clientLength += pcl ;
rpl −= pcl ;
}
#else
clientLength = send (clientSocket , reply .data ( ), reply .length ( ), 0);
#endif
if (clientLength ≠ static cast〈int〉(reply .length ( ))) {
perror ("POP3Proxy␣relaying␣multi−line␣reply␣to␣request␣to␣client");
break;
}
#ifdef POP3_TRACE_TRANSFER_DETAIL
if (popProxyTrace ) {
}
#endif
}
cerr
≪ "POP3:␣" ≪ endl ;
cerr ≪ reply ;
cerr ≪ "POP3:␣" ≪ endl ;
This code is cited in section 256.
This code is used in section 204.