class FFI::Pointer

# File lib/puppet/util/windows/api_types.rb, line 61
def read_arbitrary_wide_string_up_to(max_char_length = 512)
  # max_char_length is number of wide chars (typically excluding NULLs), *not* bytes
  # use a pointer to read one UTF-16LE char (2 bytes) at a time
  wchar_ptr = FFI::Pointer.new(:wchar, address)

  # now iterate 2 bytes at a time until an offset lower than max_char_length is found
  0.upto(max_char_length - 1) do |i|
    if wchar_ptr[i].read_wchar == NULL_TERMINATOR_WCHAR
      return read_wide_string(i)
    end
  end

  read_wide_string(max_char_length)
end

# File lib/puppet/util/windows/api_types.rb, line 93
def read_com_memory_pointer(&block)
  ptr = nil
  begin
    ptr = read_pointer
    yield ptr
  ensure
    FFI::WIN32::CoTaskMemFree(ptr) if ptr && ! ptr.null?
  end

  # ptr has already had CoTaskMemFree called, so nothing to return
  nil
end

# File lib/puppet/util/windows/api_types.rb, line 48
def read_handle
  type_size == 4 ? read_uint32 : read_uint64
end

# File lib/puppet/util/windows/api_types.rb, line 55
def read_wide_string(char_length)
  # char_length is number of wide chars (typically excluding NULLs), *not* bytes
  str = get_bytes(0, char_length * 2).force_encoding('UTF-16LE')
  str.encode(Encoding.default_external)
end

# File lib/puppet/util/windows/api_types.rb, line 37
def read_win32_bool
  # BOOL is always a 32-bit integer in Win32
  # some Win32 APIs return 1 for true, while others are non-0
  read_int32 != FFI::WIN32_FALSE
end

# File lib/puppet/util/windows/api_types.rb, line 76
def read_win32_local_pointer(&block)
  ptr = nil
  begin
    ptr = read_pointer
    yield ptr
  ensure
    if ptr && ! ptr.null?
      if FFI::WIN32::LocalFree(ptr.address) != FFI::Pointer::NULL_HANDLE
        Puppet.debug "LocalFree memory leak"
      end
    end
  end

  # ptr has already had LocalFree called, so nothing to return
  nil
end

# File lib/puppet/util/windows/api_types.rb, line 24
def self.from_string_to_wide_string(str, &block)
  str = Puppet::Util::Windows::String.wide_string(str)
  FFI::MemoryPointer.new(:byte, str.bytesize) do |ptr|
    # uchar here is synonymous with byte
    ptr.put_array_of_uchar(0, str.bytes.to_a)

    yield ptr
  end

  # ptr has already had free called, so nothing to return
  nil
end