libc/src/unistd/linux/link.cpp

   1 //===-- Linux implementation of link --------------------------------------===//
   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/link.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 <sys/syscall.h> // For syscall numbers.
  17
  18 namespace LIBC_NAMESPACE {
  19
  20 LLVM_LIBC_FUNCTION(int, link, (const char *path1, const char *path2)) {
  21 #ifdef SYS_link
  22   int ret = LIBC_NAMESPACE::syscall_impl<int>(SYS_link, path1, path2);
  23 #elif defined(SYS_linkat)
  24   int ret = LIBC_NAMESPACE::syscall_impl<int>(SYS_linkat, AT_FDCWD, path1,
  25                                               AT_FDCWD, path2, 0);
  26 #else
  27 #error "link or linkat syscalls not available."
  28 #endif
  29   if (ret < 0) {
  30     libc_errno = -ret;
  31     return -1;
  32   }
  33   return ret;
  34 }
  35
  36 } // namespace LIBC_NAMESPACE