libc/src/__support/OSUtil/linux/syscall_wrappers/link.h

//===-- Implementation header for link --------------------------*- C++ -*-===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//

#ifndef LLVM_LIBC_SRC___SUPPORT_OSUTIL_LINUX_SYSCALL_WRAPPERS_LINK_H
#define LLVM_LIBC_SRC___SUPPORT_OSUTIL_LINUX_SYSCALL_WRAPPERS_LINK_H

#include "hdr/fcntl_macros.h"                   // AT_FDCWD
#include "src/__support/OSUtil/linux/syscall.h" // syscall_impl
#include "src/__support/common.h"
#include "src/__support/error_or.h"
#include "src/__support/macros/config.h"
#include <sys/syscall.h> // For syscall numbers

namespace LIBC_NAMESPACE_DECL {
namespace linux_syscalls {

LIBC_INLINE ErrorOr<int> link(const char *oldpath, const char *newpath) {
#ifdef SYS_link
  int ret = syscall_impl<int>(SYS_link, oldpath, newpath);
#elif defined(SYS_linkat)
  int ret =
      syscall_impl<int>(SYS_linkat, AT_FDCWD, oldpath, AT_FDCWD, newpath, 0);
#else
#error "link and linkat syscalls not available."
#endif
  if (ret < 0)
    return Error(-static_cast<int>(ret));
  return 0;
}

} // namespace linux_syscalls
} // namespace LIBC_NAMESPACE_DECL

#endif // LLVM_LIBC_SRC___SUPPORT_OSUTIL_LINUX_SYSCALL_WRAPPERS_LINK_H