[PATCH] D31831: posix_fallocate isn't support on all filesystems

[Rafael Ávila de Espíndola via Phabricator via llvm-commits]

rafael added a comment.
This revision is now accepted and ready to land.

Please don't duplicate the code in the compile time and runtime checks. Can you do something like

#if defined(HAVE_POSIX_FALLOCATE)

  // If we have posix_fallocate use it. Unlike ftruncate it always allocates
  // space, so we get an error if the disk is full.

int Err = ::posix_fallocate(FD, 0, Size);
 if (!Err)

  return std::error_code();

if (Err && Err != EOPNOTSUPP)

    return std::error_code(Err, std::generic_category());
  
  // Add a comment about which file systems don't support posix_fallocate.

#endif

  // Use ftruncate as a fallback. It may or may not allocate space. At least on
  // OS X with HFS+ it does.
  if (::ftruncate(FD, Size) == -1)
    return std::error_code(errno, std::generic_category());


Repository:
  rL LLVM

https://reviews.llvm.org/D31831