ratatoskr-messenger/lib/ZOpenPort.c

74 lines
1.6 KiB
C

/* This file is part of the Project Athena Zephyr Notification System.
* It contains source for the ZOpenPort function.
*
* Created by: Robert French
*
* $Id$
*
* Copyright (c) 1987 by the Massachusetts Institute of Technology.
* For copying and distribution information, see the file
* "mit-copyright.h".
*/
#ifndef lint
static const char rcsid_ZOpenPort_c[] = "$Id$";
#endif
#include <internal.h>
#include <sys/socket.h>
Code_t
ZOpenPort(u_short *port)
{
struct sockaddr_in bindin;
unsigned int len;
int val = 1;
(void) ZClosePort();
if ((__Zephyr_fd = socket(AF_INET, SOCK_DGRAM, 0)) < 0) {
__Zephyr_fd = -1;
return errno;
}
bindin.sin_family = AF_INET;
if (port && *port) {
bindin.sin_port = *port;
if (setsockopt(__Zephyr_fd, SOL_SOCKET, SO_REUSEADDR, &val, sizeof val) < 0)
return errno;
} else {
bindin.sin_port = 0;
}
bindin.sin_addr.s_addr = INADDR_ANY;
if (bind(__Zephyr_fd, (struct sockaddr *)&bindin, sizeof(bindin)) < 0) {
if (errno == EADDRINUSE && port && *port)
return ZERR_PORTINUSE;
else
return errno;
}
if (port && *port) {
/* turn SO_REUSEADDR back off so no one else can steal it */
val = 0;
if (setsockopt(__Zephyr_fd, SOL_SOCKET, SO_REUSEADDR, &val, sizeof val) < 0)
return errno;
}
if (!bindin.sin_port) {
len = sizeof(bindin);
if (getsockname(__Zephyr_fd, (struct sockaddr *)&bindin, &len))
return errno;
}
__Zephyr_port = bindin.sin_port;
__Zephyr_open = 1;
if (port)
*port = bindin.sin_port;
return ZERR_NONE;
}