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/*++
/* NAME
/* sane_connect 3
/* SUMMARY
/* sanitize connect() results
/* SYNOPSIS
/* #include <sane_connect.h>
/*
/* int sane_connect(sock, buf, len)
/* int sock;
/* struct sockaddr *buf;
/* SOCKADDR_SIZE *len;
/* DESCRIPTION
/* sane_connect() implements the connect(2) socket call, and maps
/* known harmless error results to EAGAIN.
/* BUGS
/* Bizarre systems may have other harmless error results. Such
/* systems encourage programmers to ignore error results, and
/* penalize programmers who code defensively.
/* LICENSE
/* .ad
/* .fi
/* The Secure Mailer license must be distributed with this software.
/* AUTHOR(S)
/* Wietse Venema
/* IBM T.J. Watson Research
/* P.O. Box 704
/* Yorktown Heights, NY 10598, USA
/*--*/
/* System library. */
#include "sys_defs.h"
#include <sys/socket.h>
#include <errno.h>
/* Utility library. */
#include "msg.h"
#include "sane_connect.h"
/* sane_connect - sanitize connect() results */
int sane_connect(int sock, struct sockaddr *sa, SOCKADDR_SIZE len)
{
/*
* XXX Solaris select() produces false read events, so that read() blocks
* forever on a blocking socket, and fails with EAGAIN on a non-blocking
* socket. Turning on keepalives will fix a blocking socket provided that
* the kernel's keepalive timer expires before the Postfix watchdog
* timer.
*
* XXX Work around NAT induced damage by sending a keepalive before an idle
* connection is expired. This requires that the kernel keepalive timer
* is set to a short time, like 100s.
*/
if (sa->sa_family == AF_INET) {
int on = 1;
(void) setsockopt(sock, SOL_SOCKET, SO_KEEPALIVE,
(void *) &on, sizeof(on));
}
return (connect(sock, sa, len));
}
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