11.4Skre/*	$NetBSD: compat_dup3.c,v 1.4 2025/08/06 23:51:16 kre Exp $ */
21.1Schristos
31.1Schristos/*-
41.1Schristos * Copyright (c) 2024 The NetBSD Foundation, Inc.
51.1Schristos * All rights reserved.
61.1Schristos *
71.1Schristos * This code is derived from software contributed to The NetBSD Foundation
81.1Schristos * by Christos Zoulas.
91.1Schristos *
101.1Schristos * Redistribution and use in source and binary forms, with or without
111.1Schristos * modification, are permitted provided that the following conditions
121.1Schristos * are met:
131.1Schristos * 1. Redistributions of source code must retain the above copyright
141.1Schristos *    notice, this list of conditions and the following disclaimer.
151.1Schristos * 2. Redistributions in binary form must reproduce the above copyright
161.1Schristos *    notice, this list of conditions and the following disclaimer in the
171.1Schristos *    documentation and/or other materials provided with the distribution.
181.1Schristos *
191.1Schristos * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
201.1Schristos * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
211.1Schristos * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
221.1Schristos * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
231.1Schristos * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
241.1Schristos * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
251.1Schristos * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
261.1Schristos * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
271.1Schristos * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
281.1Schristos * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
291.1Schristos * POSSIBILITY OF SUCH DAMAGE.
301.1Schristos */
311.1Schristos#include <sys/cdefs.h>
321.1Schristos#if defined(LIBC_SCCS) && !defined(lint)
331.4Skre__RCSID("$NetBSD: compat_dup3.c,v 1.4 2025/08/06 23:51:16 kre Exp $");
341.1Schristos#endif /* LIBC_SCCS and not lint */
351.1Schristos
361.1Schristos#include "namespace.h"
371.1Schristos#define __LIBC12_SOURCE__
381.1Schristos#include <fcntl.h>
391.1Schristos#include <compat/include/unistd.h>
401.1Schristos
411.1Schristos__warn_references(dup3,
421.1Schristos    "warning: reference to compatibility dup3(); include <unistd.h> to generate correct reference")
431.1Schristos
441.1Schristosint
451.1Schristosdup3(int oldfd, int newfd, int flags)
461.1Schristos{
471.3Skre	int fdflags;
481.3Skre
491.1Schristos	if (oldfd != newfd) {
501.2Schristos		return __dup3100(oldfd, newfd, flags);
511.1Schristos	}
521.1Schristos	if (flags & (O_NONBLOCK|O_NOSIGPIPE)) {
531.1Schristos		int e = fcntl(newfd, F_GETFL, 0);
541.1Schristos		if (e == -1)
551.1Schristos			return -1;
561.1Schristos		e |= flags & (O_NONBLOCK|O_NOSIGPIPE);
571.1Schristos		e = fcntl(newfd, F_SETFL, e);
581.1Schristos		if (e == -1)
591.1Schristos			return -1;
601.1Schristos	}
611.3Skre
621.3Skre	switch (flags & (O_CLOEXEC|O_CLOFORK)) {
631.3Skre	case O_CLOEXEC|O_CLOFORK:
641.3Skre		fdflags = FD_CLOEXEC|FD_CLOFORK;
651.3Skre		break;
661.3Skre	case O_CLOEXEC:
671.3Skre		fdflags = FD_CLOEXEC;
681.3Skre		break;
691.3Skre	case O_CLOFORK:
701.3Skre		fdflags = FD_CLOFORK;
711.3Skre		break;
721.3Skre	default:
731.3Skre		return 0;
741.3Skre	}
751.3Skre	return fcntl(newfd, F_SETFD, fdflags);
761.1Schristos}
77