Fix Unicode handling for ostream under Windows with libc++. (#3001)

Also replaces the SFIANE tricks applied in
ce7ecdb7af with conditional compilation.
The code was too complicated along with the other trick to access private
data members.
This commit is contained in:
Dimitrij Mijoski
2022-07-30 15:49:21 +02:00
committed by GitHub
parent 0b2862a1e4
commit 756822ba39

View File

@ -13,6 +13,8 @@
#if defined(_WIN32) && defined(__GLIBCXX__)
# include <ext/stdio_filebuf.h>
# include <ext/stdio_sync_filebuf.h>
#elif defined(_WIN32) && defined(_LIBCPP_VERSION)
# include <__std_stream>
#endif
#include "format.h"
@ -55,35 +57,25 @@ struct is_streamable<
(std::is_convertible<T, int>::value && !std::is_enum<T>::value)>>
: std::false_type {};
template <typename Char> FILE* get_file(std::basic_filebuf<Char>&) {
return nullptr;
}
struct dummy_filebuf {
FILE* _Myfile;
};
template <typename T, typename U = int> struct ms_filebuf {
using type = dummy_filebuf;
};
template <typename T> struct ms_filebuf<T, decltype(T::_Myfile, 0)> {
using type = T;
};
using filebuf_type = ms_filebuf<std::filebuf>::type;
FILE* get_file(filebuf_type& buf);
// Generate a unique explicit instantion in every translation unit using a tag
// type in an anonymous namespace.
namespace {
struct filebuf_access_tag {};
struct file_access_tag {};
} // namespace
template <typename Tag, typename FileMemberPtr, FileMemberPtr file>
class filebuf_access {
friend FILE* get_file(filebuf_type& buf) { return buf.*file; }
template <class Tag, class BufType, FILE* BufType::*FileMemberPtr>
class file_access {
friend auto get_file(BufType& obj) -> FILE* { return obj.*FileMemberPtr; }
};
template class filebuf_access<filebuf_access_tag,
decltype(&filebuf_type::_Myfile),
&filebuf_type::_Myfile>;
#if FMT_MSC_VERSION
template class file_access<file_access_tag, std::filebuf,
&std::filebuf::_Myfile>;
auto get_file(std::filebuf&) -> FILE*;
#elif defined(_WIN32) && defined(_LIBCPP_VERSION)
template class file_access<file_access_tag, std::__stdoutbuf<char>,
&std::__stdoutbuf<char>::__file_>;
auto get_file(std::__stdoutbuf<char>&) -> FILE*;
#endif
inline bool write_ostream_unicode(std::ostream& os, fmt::string_view data) {
#if FMT_MSC_VERSION
@ -99,6 +91,9 @@ inline bool write_ostream_unicode(std::ostream& os, fmt::string_view data) {
else
return false;
if (c_file) return write_console(c_file, data);
#elif defined(_WIN32) && defined(_LIBCPP_VERSION)
if (auto* buf = dynamic_cast<std::__stdoutbuf<char>*>(os.rdbuf()))
if (FILE* f = get_file(*buf)) return write_console(f, data);
#else
ignore_unused(os);
ignore_unused(data);