1 /* $NetBSD: rpc_dtablesize.c,v 1.14 1998/11/15 17:32:43 christos Exp $ */ 2 3 /*- 4 * SPDX-License-Identifier: BSD-3-Clause 5 * 6 * Copyright (c) 2009, Sun Microsystems, Inc. 7 * All rights reserved. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions are met: 11 * - Redistributions of source code must retain the above copyright notice, 12 * this list of conditions and the following disclaimer. 13 * - Redistributions in binary form must reproduce the above copyright notice, 14 * this list of conditions and the following disclaimer in the documentation 15 * and/or other materials provided with the distribution. 16 * - Neither the name of Sun Microsystems, Inc. nor the names of its 17 * contributors may be used to endorse or promote products derived 18 * from this software without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 21 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE 24 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 25 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 26 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 27 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 28 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 29 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 30 * POSSIBILITY OF SUCH DAMAGE. 31 */ 32 33 #include "namespace.h" 34 #include <unistd.h> 35 #include "un-namespace.h" 36 37 int _rpc_dtablesize(void); /* XXX */ 38 39 /* 40 * Cache the result of getdtablesize(), so we don't have to do an 41 * expensive system call every time. 42 */ 43 /* 44 * XXX In FreeBSD 2.x, you can have the maximum number of open file 45 * descriptors be greater than FD_SETSIZE (which us 256 by default). 46 * 47 * Since old programs tend to use this call to determine the first arg 48 * for _select(), having this return > FD_SETSIZE is a Bad Idea(TM)! 49 */ 50 int 51 _rpc_dtablesize(void) 52 { 53 static int size; 54 55 if (size == 0) { 56 size = getdtablesize(); 57 if (size > FD_SETSIZE) 58 size = FD_SETSIZE; 59 } 60 return (size); 61 } 62