/* await_contact.c */#include <cnaiapi.h>/*----------------------------------------------------------------------- * await_contact - accept a connection on port a. If no master sock is * already open for the port, create one and record it in the port-to- * socket table. *----------------------------------------------------------------------- */connectionawait_contact(appnum a){	struct sockaddr_in	sockaddr, csockaddr;	int			sock, newsock, i, csockaddrlen;	static int		p2sinit = 0;	static struct port2sock	p2s[P2S_SIZE];	cnaiapi_init();		if (a == 0)		return -1;#if defined(LINUX) || defined(SOLARIS)	pthread_mutex_lock(&await_contact_mutex);#elif defined(WIN32)	WaitForSingleObject(await_contact_mutex, INFINITE);#endif		if (p2sinit == 0) {			(void) memset(p2s, 0, sizeof(p2s));			p2sinit = 1;		}	/* look up master socket in port-to-socket table */	for (sock = -1, i = 0; i < P2S_SIZE; i++) {		if (p2s[i].port == a) {			sock = p2s[i].sock;			break;		}	}	if (sock == -1) {		/* open new master socket */		/* look for room in p2s table */		for (i = 0; i < P2S_SIZE; i++) {			if (p2s[i].port == 0)				break;		}		if (i == P2S_SIZE) {			/* no room left in p2s */#if defined(LINUX) || defined(SOLARIS)			pthread_mutex_unlock(&await_contact_mutex);#elif defined(WIN32)			ReleaseMutex(await_contact_mutex);#endif			return -1;		}		sock = socket(PF_INET, SOCK_STREAM, 0);		if (sock < 0) {#if defined(LINUX) || defined(SOLARIS)			pthread_mutex_unlock(&await_contact_mutex);#elif defined(WIN32)			ReleaseMutex(await_contact_mutex);#endif			return -1;		}		(void) memset(&sockaddr, 0, sizeof(struct sockaddr_in));		sockaddr.sin_family = AF_INET;		sockaddr.sin_port = htons(a);		sockaddr.sin_addr.s_addr = htonl(INADDR_ANY);		if (bind(sock, (struct sockaddr *) &sockaddr,			 sizeof(struct sockaddr_in)) < 0 ||		    listen(sock, LISTEN_Q_LEN) < 0) {#if defined(LINUX) || defined(SOLARIS)			close(sock);			pthread_mutex_unlock(&await_contact_mutex);#elif defined(WIN32)			closesocket(sock);			ReleaseMutex(await_contact_mutex);#endif			return -1;		}		/* record master socket in table */		p2s[i].sock = sock;		p2s[i].port = a;	}#if defined(LINUX) || defined(SOLARIS)	pthread_mutex_unlock(&await_contact_mutex);#elif defined(WIN32)	ReleaseMutex(await_contact_mutex);#endif	csockaddrlen = sizeof(struct sockaddr_in);	newsock = accept(sock, (struct sockaddr *) &csockaddr, &csockaddrlen);	return newsock;}