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