freebsd-nq/lib/libc/sys/openat.c
Conrad Meyer 1e72c52e23 libc: partially revert r326576
In r326576 ("use @@@ instead of @@ in __sym_default"), an earlier version of
the phabricator-discussed patch was inadvertently committed.  The commit
message claims that @@@ means that weak is not needed, but that was due to a
misunderstanding of the use of weak symbols in this context by the submitted
in the first draft of the patch; the description text was not updated to
match the discussion.  As discussed in phabricator, weak is needed for
symbol interposing because of the behavior of our rtld, and is widely used
elsewhere in libc.

This partial revert restores the approved version of the patch and permits
symbol interposing for openat.

Reported by:	Raymond Ramsden <rramsden AT isilon.com>
Reviewed by:	dim, emaste, kib (2017)
Discussed with:	kib (2020)
Differential Revision:	https://reviews.freebsd.org/D11653
2020-04-25 14:24:54 +00:00

63 lines
2.2 KiB
C

/*
* Copyright (c) 2014 The FreeBSD Foundation.
* All rights reserved.
*
* Portions of this software were developed by Konstantin Belousov
* under sponsorship from the FreeBSD Foundation.
*
* 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(s), this list of conditions and the following disclaimer as
* the first lines of this file unmodified other than the possible
* addition of one or more copyright notices.
* 2. Redistributions in binary form must reproduce the above copyright
* notice(s), 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 COPYRIGHT HOLDER(S) ``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(S) 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 <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/types.h>
#include <sys/fcntl.h>
#include <stdarg.h>
#include "libc_private.h"
__weak_reference(__sys_openat, __openat);
__sym_compat(openat, __impl_openat, FBSD_1.1);
__weak_reference(openat, __impl_openat);
__sym_default(openat, openat, FBSD_1.2);
#pragma weak openat
int
openat(int fd, const char *path, int flags, ...)
{
va_list ap;
int mode;
if ((flags & O_CREAT) != 0) {
va_start(ap, flags);
mode = va_arg(ap, int);
va_end(ap);
} else {
mode = 0;
}
return (((int (*)(int, const char *, int, ...))
__libc_interposing[INTERPOS_openat])(fd, path, flags, mode));
}