rpc_dtablesize.c

/* @(#)rpc_dtablesize.c	2.1 88/07/29 4.0 RPCSRC */
/*
 * Copyright (c) 2010, Oracle America, Inc.
 *
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 *     * Redistributions of source code must retain the above copyright
 *       notice, this list of conditions and the following disclaimer.
 *
 *     * Redistributions in binary form must reproduce the above copyright
 *       notice, this list of conditions and the following disclaimer in
 *       the documentation and/or other materials provided with the
 *       distribution.
 *
 *     * Neither the name of the "Oracle America, Inc." nor the names of
 *       its contributors may be used to endorse or promote products
 *       derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
 * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
 * PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
 * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
#if !defined(lint) && defined(SCCSIDS)
static char sccsid[] = "@(#)rpc_dtablesize.c 1.2 87/08/11 Copyr 1987 Sun Micro";
#endif

#include <unistd.h>
#include <gssrpc/rpc.h>

/*
 * Cache the result of getdtablesize(), so we don't have to do an
 * expensive system call every time.
 */
int
gssrpc__rpc_dtablesize(void)
{
	static int size;

	if (size == 0) {
#ifdef _SC_OPEN_MAX
	    size = (int) sysconf(_SC_OPEN_MAX);
#else
	    size = getdtablesize();
#endif

/* sysconf() can return a number larger than what will fit in an
   fd_set.  we can't use fd's larger than this, anyway. */

#ifdef FD_SETSIZE
	    if (size >= FD_SETSIZE)
		size = FD_SETSIZE-1;
#endif
	}
	return (size);
}