+/*
+ * Perform a non-blocking connect on the socket fd.
+ *
+ * tout contains the timeout. It will be modified to contain the time
+ * remaining (i.e. time provided - time elasped).
+ */
+static int connect_nb(int fd, struct sockaddr_in *addr, struct timeval *tout)
+{
+ int flags, ret;
+ socklen_t len;
+ fd_set rset;
+
+ flags = fcntl(fd, F_GETFL, 0);
+ if (flags < 0)
+ return -1;
+
+ ret = fcntl(fd, F_SETFL, flags | O_NONBLOCK);
+ if (ret < 0)
+ return -1;
+
+ /*
+ * From here on subsequent sys calls could change errno so
+ * we set ret = -errno to capture it in case we decide to
+ * use it later.
+ */
+ len = sizeof(struct sockaddr);
+ ret = connect(fd, (struct sockaddr *)addr, len);
+ if (ret < 0 && errno != EINPROGRESS) {
+ ret = -errno;
+ goto done;
+ }
+
+ if (ret == 0)
+ goto done;
+
+ /* now wait */
+ FD_ZERO(&rset);
+ FD_SET(fd, &rset);
+
+ ret = select(fd + 1, &rset, NULL, NULL, tout);
+ if (ret <= 0) {
+ if (ret == 0)
+ ret = -ETIMEDOUT;
+ else
+ ret = -errno;
+ goto done;
+ }
+
+ if (FD_ISSET(fd, &rset)) {
+ int status;
+
+ len = sizeof(ret);
+ status = getsockopt(fd, SOL_SOCKET, SO_ERROR, &ret, &len);
+ if (status < 0) {
+ ret = -errno;
+ goto done;
+ }
+
+ /* Oops - something wrong with connect */
+ if (ret)
+ ret = -ret;
+ }
+
+done:
+ fcntl(fd, F_SETFL, flags);
+ return ret;
+}
+
+static unsigned short getport(struct sockaddr_in *addr,
+ unsigned long prog, unsigned long vers, int prot)
+{
+ CLIENT *client;
+ enum clnt_stat status;
+ struct pmap parms;
+ int ret, sock;
+ struct sockaddr_in laddr, saddr;
+ struct timeval tout = {0, 0};
+ socklen_t len;
+ unsigned int send_sz = 0;
+ unsigned int recv_sz = 0;
+ unsigned short port;
+
+ memset(&laddr, 0, sizeof(laddr));
+ memset(&saddr, 0, sizeof(saddr));
+ memset(&parms, 0, sizeof(parms));
+
+ memcpy(&saddr, addr, sizeof(saddr));
+ saddr.sin_port = htons(PMAPPORT);
+
+ if (prot == IPPROTO_TCP) {
+ sock = socket(PF_INET, SOCK_STREAM, IPPROTO_TCP);
+ if (sock == -1) {
+ rpc_createerr.cf_stat = RPC_SYSTEMERROR;
+ rpc_createerr.cf_error.re_errno = errno;
+ return 0;
+ }
+
+ tout.tv_sec = TIMEOUT_TCP;
+
+ ret = connect_nb(sock, &saddr, &tout);
+ if (ret == -1) {
+ close(sock);
+ rpc_createerr.cf_stat = RPC_SYSTEMERROR;
+ rpc_createerr.cf_error.re_errno = errno;
+ return 0;
+ }
+ } else {
+ /*
+ * bind to any unused port. If we left this up to the rpc
+ * layer, it would bind to a reserved port, which has been shown
+ * to exhaust the reserved port range in some situations.
+ */
+ sock = socket(PF_INET, SOCK_DGRAM, IPPROTO_UDP);
+ if (sock == -1) {
+ rpc_createerr.cf_stat = RPC_SYSTEMERROR;
+ rpc_createerr.cf_error.re_errno = errno;
+ return 0;
+ }
+
+ laddr.sin_family = AF_INET;
+ laddr.sin_port = 0;
+ laddr.sin_addr.s_addr = htonl(INADDR_ANY);
+
+ tout.tv_sec = TIMEOUT_UDP;
+
+ send_sz = RPCSMALLMSGSIZE;
+ recv_sz = RPCSMALLMSGSIZE;
+
+ len = sizeof(struct sockaddr_in);
+ if (bind(sock, (struct sockaddr *)&laddr, len) < 0) {
+ close(sock);
+ sock = RPC_ANYSOCK;
+ /* FALLTHROUGH */
+ }
+ }
+
+ client = clntudp_bufcreate(&saddr, PMAPPROG, PMAPVERS,
+ tout, &sock, send_sz, recv_sz);
+ if (!client) {
+ close(sock);
+ rpc_createerr.cf_stat = RPC_RPCBFAILURE;
+ return 0;
+ }
+
+ clnt_control(client, CLSET_FD_CLOSE, NULL);
+
+ parms.pm_prog = prog;
+ parms.pm_vers = vers;
+ parms.pm_prot = prot;
+
+ status = clnt_call(client, PMAPPROC_GETPORT,
+ (xdrproc_t) xdr_pmap, (caddr_t) &parms,
+ (xdrproc_t) xdr_u_short, (caddr_t) &port,
+ tout);
+
+ if (status != RPC_SUCCESS) {
+ clnt_geterr(client, &rpc_createerr.cf_error);
+ rpc_createerr.cf_stat = status;
+ clnt_destroy(client);
+ return 0;
+ }
+
+ clnt_destroy(client);
+
+ return htons(port);
+}
+