libc/src/unistd/linux/access.cpp

   1 //===-- Linux implementation of access ------------------------------------===//
   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/unistd/access.h"
  10
  11 #include "src/__support/OSUtil/syscall.h" // For internal syscall function.
  12 #include "src/__support/common.h"
  13
  14 #include "src/errno/libc_errno.h"
  15 #include <fcntl.h>
  16 #include <sys/syscall.h> // For syscall numbers.
  17
  18 namespace LIBC_NAMESPACE {
  19
  20 LLVM_LIBC_FUNCTION(int, access, (const char *path, int mode)) {
  21 #ifdef SYS_access
  22   int ret = LIBC_NAMESPACE::syscall_impl<int>(SYS_access, path, mode);
  23 #elif defined(SYS_faccessat)
  24   int ret =
  25       LIBC_NAMESPACE::syscall_impl<int>(SYS_faccessat, AT_FDCWD, path, mode, 0);
  26 #else
  27 #error "access and faccessat syscalls not available."
  28 #endif
  29
  30   if (ret < 0) {
  31     libc_errno = -ret;
  32     return -1;
  33   }
  34   return 0;
  35 }
  36
  37 } // namespace LIBC_NAMESPACE