1//===-- Implementation of open --------------------------------------------===//
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/open.h"
10
11#include "src/__support/OSUtil/syscall.h" // For internal syscall function.
12#include "src/__support/common.h"
13#include "src/errno/libc_errno.h"
14
15#include <fcntl.h>
16#include <stdarg.h>
17#include <sys/syscall.h> // For syscall numbers.
18
19namespace LIBC_NAMESPACE {
20
21LLVM_LIBC_FUNCTION(int, open, (const char *path, int flags, ...)) {
22 mode_t mode_flags = 0;
23 // O_TMPFILE is a multi-bit flag so we test all bits by checking for equality
24 // with O_TMPFILE
25 if ((flags & O_CREAT) || (flags & O_TMPFILE) == O_TMPFILE) {
26 va_list varargs;
27 va_start(varargs, flags);
28 mode_flags = va_arg(varargs, mode_t);
29 va_end(varargs);
30 }
31
32#ifdef SYS_open
33 int fd = LIBC_NAMESPACE::syscall_impl<int>(SYS_open, ts: path, ts: flags, ts: mode_flags);
34#else
35 int fd = LIBC_NAMESPACE::syscall_impl<int>(SYS_openat, AT_FDCWD, path, flags,
36 mode_flags);
37#endif
38 if (fd > 0)
39 return fd;
40
41 libc_errno = -fd;
42 return -1;
43}
44
45} // namespace LIBC_NAMESPACE
46

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