libcxx/src/ostream.cpp

   1 //===----------------------------------------------------------------------===//
   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 <__config>
  10 #if _LIBCPP_HAS_FILESYSTEM
  11 #  include <fstream>
  12 #endif
  13 #include <ostream>
  14
  15 #include "std_stream.h"
  16
  17 _LIBCPP_BEGIN_NAMESPACE_STD
  18
  19 _LIBCPP_EXPORTED_FROM_ABI FILE* __get_ostream_file(ostream& __os) {
  20   // dynamic_cast requires RTTI, this only affects users whose vendor builds
  21   // the dylib with RTTI disabled. It does not affect users who build with RTTI
  22   // disabled but use a dylib where the RTTI is enabled.
  23   //
  24   // Returning a nullptr means the stream is not considered a terminal and the
  25   // special terminal handling is not done. The terminal handling is mainly of
  26   // importance on Windows.
  27 #if _LIBCPP_HAS_RTTI
  28   auto* __rdbuf = __os.rdbuf();
  29 #  if _LIBCPP_HAS_FILESYSTEM
  30   if (auto* __buffer = dynamic_cast<filebuf*>(__rdbuf))
  31     return __buffer->__file_;
  32 #  endif
  33
  34   if (auto* __buffer = dynamic_cast<__stdoutbuf<char>*>(__rdbuf))
  35     return __buffer->__file_;
  36 #endif // _LIBCPP_HAS_RTTI
  37
  38   return nullptr;
  39 }
  40
  41 _LIBCPP_END_NAMESPACE_STD