• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
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/errno/libc_errno.h"
14 
15 #include <fcntl.h>
16 #include <stdarg.h>
17 #include <sys/syscall.h> // For syscall numbers.
18 
19 namespace LIBC_NAMESPACE {
20 
21 LLVM_LIBC_FUNCTION(int, openat, (int dfd, 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   int fd = LIBC_NAMESPACE::syscall_impl<int>(SYS_openat, dfd, path, flags,
33                                              mode_flags);
34   if (fd > 0)
35     return fd;
36 
37   libc_errno = -fd;
38   return -1;
39 }
40 
41 } // namespace LIBC_NAMESPACE
42