1 files changed, 61 insertions, 0 deletions
diff --git a/lib/libc/gen/dup3.c b/lib/libc/gen/dup3.c
new file mode 100644
index 000000000000..1401c1f5b607
--- /dev/null
+++ b/lib/libc/gen/dup3.c
@@ -0,0 +1,61 @@
+/*-
+ * SPDX-License-Identifier: BSD-2-Clause
+ *
+ * Copyright (c) 2012 Jukka A. Ukkonen
+ * All rights reserved.
+ *
+ * This software was developed by Jukka Ukkonen for FreeBSD.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. 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.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.
+ */
+
+#include "namespace.h"
+#include <unistd.h>
+#include <fcntl.h>
+#include <errno.h>
+#include "un-namespace.h"
+
+int __dup3(int, int, int);
+
+int
+__dup3(int oldfd, int newfd, int flags)
+{
+	int fdflags;
+
+	if (oldfd == newfd) {
+		errno = EINVAL;
+		return (-1);
+	}
+
+	if ((flags & ~(O_CLOEXEC | O_CLOFORK)) != 0) {
+		errno = EINVAL;
+		return (-1);
+	}
+
+	fdflags = ((flags & O_CLOEXEC) != 0 ? FD_CLOEXEC : 0) |
+	    ((flags & O_CLOFORK) != 0 ? FD_CLOFORK : 0);
+
+	return (_fcntl(oldfd, F_DUP3FD | (fdflags << F_DUP3FD_SHIFT), newfd));
+}
+
+__weak_reference(__dup3, dup3);
+__weak_reference(__dup3, _dup3);