clnt_udp.c

RTEMS (Real-Time Executive for Multiprocessor Systems) is a free open source real-time operating sys

	if (!timerisset(&timeout)) {
		if (fds != &readfds)
			free(fds);
		return (cu->cu_error.re_status = RPC_TIMEDOUT);
	}
	/*
	 * sub-optimal code appears here because we have
	 * some clock time to spare while the packets are in flight.
	 * (We assume that this is actually only executed once.)
	 */
	reply_msg.acpted_rply.ar_verf = _null_auth;
	reply_msg.acpted_rply.ar_results.where = resultsp;
	reply_msg.acpted_rply.ar_results.proc = xresults;

	gettimeofday(&start, NULL);
	for (;;) {
		/* XXX we know the other bits are still clear */
		FD_SET(cu->cu_sock, fds);
		tv = cu->cu_wait;
		switch (select(cu->cu_sock+1, fds, NULL, NULL, &tv)) {

		case 0:
			timeradd(&time_waited, &cu->cu_wait, &tmp1);
			time_waited = tmp1;
			if (timercmp(&time_waited, &timeout, <))
				goto send_again;
			if (fds != &readfds)
				free(fds);
			return (cu->cu_error.re_status = RPC_TIMEDOUT);

		case -1:
			if (errno == EINTR) {
				gettimeofday(&after, NULL);
				timersub(&after, &start, &tmp1);
				timeradd(&time_waited, &tmp1, &tmp2);
				time_waited = tmp2;
				if (timercmp(&time_waited, &timeout, <))
					continue;
				if (fds != &readfds)
					free(fds);
				return (cu->cu_error.re_status = RPC_TIMEDOUT);
			}
			cu->cu_error.re_errno = errno;
			if (fds != &readfds)
				free(fds);
			return (cu->cu_error.re_status = RPC_CANTRECV);
		}

		do {
			fromlen = sizeof(struct sockaddr);
			inlen = recvfrom(cu->cu_sock, cu->cu_inbuf,
				(int) cu->cu_recvsz, 0,
				(struct sockaddr *)&from, &fromlen);
		} while (inlen < 0 && errno == EINTR);
		if (inlen < 0) {
			if (errno == EWOULDBLOCK)
				continue;
			cu->cu_error.re_errno = errno;
			if (fds != &readfds)
				free(fds);
			return (cu->cu_error.re_status = RPC_CANTRECV);
		}
		if (inlen < sizeof(u_int32_t))
			continue;
		/* see if reply transaction id matches sent id */
		if (*((u_int32_t *)(cu->cu_inbuf)) != *((u_int32_t *)(cu->cu_outbuf)))
			continue;
		/* we now assume we have the proper reply */
		break;
	}

	/*
	 * now decode and validate the response
	 */
	xdrmem_create(&reply_xdrs, cu->cu_inbuf, (u_int)inlen, XDR_DECODE);
	ok = xdr_replymsg(&reply_xdrs, &reply_msg);
	/* XDR_DESTROY(&reply_xdrs);  save a few cycles on noop destroy */
	if (ok) {
		_seterr_reply(&reply_msg, &(cu->cu_error));
		if (cu->cu_error.re_status == RPC_SUCCESS) {
			if (! AUTH_VALIDATE(cl->cl_auth,
				&reply_msg.acpted_rply.ar_verf)) {
				cu->cu_error.re_status = RPC_AUTHERROR;
				cu->cu_error.re_why = AUTH_INVALIDRESP;
			}
			if (reply_msg.acpted_rply.ar_verf.oa_base != NULL) {
				xdrs->x_op = XDR_FREE;
				(void)xdr_opaque_auth(xdrs,
				    &(reply_msg.acpted_rply.ar_verf));
			}
		}  /* end successful completion */
		else {
			/* maybe our credentials need to be refreshed ... */
			if (nrefreshes > 0 && AUTH_REFRESH(cl->cl_auth)) {
				nrefreshes--;
				goto call_again;
			}
		}  /* end of unsuccessful completion */
	}  /* end of valid reply message */
	else {
		/*
		 * It's possible for xdr_replymsg() to fail partway
		 * through its attempt to decode the result from the
		 * server. If this happens, it will leave the reply
		 * structure partially populated with dynamically
		 * allocated memory. (This can happen if someone uses
		 * clntudp_bufcreate() to create a CLIENT handle and
		 * specifies a receive buffer size that is too small.)
		 * This memory must be free()ed to avoid a leak.
		 */
		int op = reply_xdrs.x_op;
		reply_xdrs.x_op = XDR_FREE;
		xdr_replymsg(&reply_xdrs, &reply_msg);
		reply_xdrs.x_op = op;
		cu->cu_error.re_status = RPC_CANTDECODERES;
	}
	if (fds != &readfds)
		free(fds);
	return (cu->cu_error.re_status);
}

static void
clntudp_geterr(cl, errp)
	CLIENT *cl;
	struct rpc_err *errp;
{
	register struct cu_data *cu = (struct cu_data *)cl->cl_private;

	*errp = cu->cu_error;
}


static bool_t
clntudp_freeres(cl, xdr_res, res_ptr)
	CLIENT *cl;
	xdrproc_t xdr_res;
	caddr_t res_ptr;
{
	register struct cu_data *cu = (struct cu_data *)cl->cl_private;
	register XDR *xdrs = &(cu->cu_outxdrs);

	xdrs->x_op = XDR_FREE;
	return ((*xdr_res)(xdrs, res_ptr));
}

static void
clntudp_abort(/*h*/)
	/*CLIENT *h;*/
{
}


static bool_t
clntudp_control(cl, request, info)
	CLIENT *cl;
	int request;
	char *info;
{
	register struct cu_data *cu = (struct cu_data *)cl->cl_private;
	register struct timeval *tv;
	int len;

	switch (request) {
	case CLSET_FD_CLOSE:
		cu->cu_closeit = TRUE;
		break;
	case CLSET_FD_NCLOSE:
		cu->cu_closeit = FALSE;
		break;
	case CLSET_TIMEOUT:
		if (info == NULL)
			return(FALSE);
		tv = (struct timeval *)info;
		cu->cu_total.tv_sec = tv->tv_sec;
		cu->cu_total.tv_usec = tv->tv_usec;
		break;
	case CLGET_TIMEOUT:
		if (info == NULL)
			return(FALSE);
		*(struct timeval *)info = cu->cu_total;
		break;
	case CLSET_RETRY_TIMEOUT:
		if (info == NULL)
			return(FALSE);
		tv = (struct timeval *)info;
		cu->cu_wait.tv_sec = tv->tv_sec;
		cu->cu_wait.tv_usec = tv->tv_usec;
		break;
	case CLGET_RETRY_TIMEOUT:
		if (info == NULL)
			return(FALSE);
		*(struct timeval *)info = cu->cu_wait;
		break;
	case CLGET_SERVER_ADDR:
		if (info == NULL)
			return(FALSE);
		*(struct sockaddr_in *)info = cu->cu_raddr;
		break;
	case CLGET_FD:
		if (info == NULL)
			return(FALSE);
		*(int *)info = cu->cu_sock;
		break;
	case CLGET_XID:
		/*
		 * use the knowledge that xid is the
		 * first element in the call structure *.
		 * This will get the xid of the PREVIOUS call
		 */
		if (info == NULL)
			return(FALSE);
		*(u_long *)info = ntohl(*(u_long *)cu->cu_outbuf);
		break;
	case CLSET_XID:
		/* This will set the xid of the NEXT call */
		if (info == NULL)
			return(FALSE);
		*(u_long *)cu->cu_outbuf =  htonl(*(u_long *)info - 1);
		/* decrement by 1 as clntudp_call() increments once */
	case CLGET_VERS:
		/*
		 * This RELIES on the information that, in the call body,
		 * the version number field is the fifth field from the
		 * begining of the RPC header. MUST be changed if the
		 * call_struct is changed
		 */
		if (info == NULL)
			return(FALSE);
		*(u_long *)info = ntohl(*(u_long *)(cu->cu_outbuf +
						4 * BYTES_PER_XDR_UNIT));
		break;
	case CLSET_VERS:
		if (info == NULL)
			return(FALSE);
		*(u_long *)(cu->cu_outbuf + 4 * BYTES_PER_XDR_UNIT)
				= htonl(*(u_long *)info);
		break;
	case CLGET_PROG:
		/*
		 * This RELIES on the information that, in the call body,
		 * the program number field is the  field from the
		 * begining of the RPC header. MUST be changed if the
		 * call_struct is changed
		 */
		if (info == NULL)
			return(FALSE);
		*(u_long *)info = ntohl(*(u_long *)(cu->cu_outbuf +
						3 * BYTES_PER_XDR_UNIT));
		break;
	case CLSET_PROG:
		if (info == NULL)
			return(FALSE);
		*(u_long *)(cu->cu_outbuf + 3 * BYTES_PER_XDR_UNIT)
				= htonl(*(u_long *)info);
		break;
	case CLGET_LOCAL_ADDR:
		len = sizeof(struct sockaddr);
		if (getsockname(cu->cu_sock, (struct sockaddr *)info, &len) <0)
			return(FALSE);
		break;
	case CLGET_SVC_ADDR:
	case CLSET_SVC_ADDR:
	case CLSET_PUSH_TIMOD:
	case CLSET_POP_TIMOD:
	default:
		return (FALSE);
	}
	return (TRUE);
}

static void
clntudp_destroy(cl)
	CLIENT *cl;
{
	register struct cu_data *cu = (struct cu_data *)cl->cl_private;

	if (cu->cu_closeit) {
		(void)_RPC_close(cu->cu_sock);
	}
	XDR_DESTROY(&(cu->cu_outxdrs));
	mem_free((caddr_t)cu, (sizeof(*cu) + cu->cu_sendsz + cu->cu_recvsz));
	mem_free((caddr_t)cl, sizeof(CLIENT));
}