1//===-- Implementation of openat ------------------------------------------===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8
9#include "src/fcntl/openat.h"
10
11#include "src/__support/OSUtil/syscall.h" // For internal syscall function.
12#include "src/__support/common.h"
13#include "src/__support/libc_errno.h"
14#include "src/__support/macros/config.h"
15
16#include "hdr/types/mode_t.h"
17#include <stdarg.h>
18#include <sys/syscall.h> // For syscall numbers.
19
20namespace LIBC_NAMESPACE_DECL {
21
22LLVM_LIBC_FUNCTION(int, openat, (int dfd, const char *path, int flags, ...)) {
23 mode_t mode_flags = 0;
24 // O_TMPFILE is a multi-bit flag so we test all bits by checking for equality
25 // with O_TMPFILE
26 if ((flags & O_CREAT) || (flags & O_TMPFILE) == O_TMPFILE) {
27 va_list varargs;
28 va_start(varargs, flags);
29 mode_flags = va_arg(varargs, mode_t);
30 va_end(varargs);
31 }
32
33 int fd = LIBC_NAMESPACE::syscall_impl<int>(SYS_openat, dfd, path, flags,
34 mode_flags);
35 if (fd > 0)
36 return fd;
37
38 libc_errno = -fd;
39 return -1;
40}
41
42} // namespace LIBC_NAMESPACE_DECL
43

source code of libc/src/fcntl/linux/openat.cpp