43 lines · cpp
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-exception6//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 equality25 // with O_TMPFILE26 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 libc_errno = -fd;37 return -1;38 }39 return fd;40}41 42} // namespace LIBC_NAMESPACE_DECL43