wxhelper-new/inc/spdlog/fmt/bundled/ostream.h
2024-06-16 13:17:24 +08:00

238 lines
7.4 KiB
C++

// Formatting library for C++ - std::ostream support
//
// Copyright (c) 2012 - present, Victor Zverovich
// All rights reserved.
//
// For the license information refer to format.h.
#ifndef FMT_OSTREAM_H_
#define FMT_OSTREAM_H_
#include <fstream>
#include <ostream>
#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"
FMT_BEGIN_NAMESPACE
template <typename OutputIt, typename Char> class basic_printf_context;
namespace detail {
// Checks if T has a user-defined operator<<.
template <typename T, typename Char, typename Enable = void>
class is_streamable {
private:
template <typename U>
static auto test(int)
-> bool_constant<sizeof(std::declval<std::basic_ostream<Char>&>()
<< std::declval<U>()) != 0>;
template <typename> static auto test(...) -> std::false_type;
using result = decltype(test<T>(0));
public:
is_streamable() = default;
static const bool value = result::value;
};
// Formatting of built-in types and arrays is intentionally disabled because
// it's handled by standard (non-ostream) formatters.
template <typename T, typename Char>
struct is_streamable<
T, Char,
enable_if_t<
std::is_arithmetic<T>::value || std::is_array<T>::value ||
std::is_pointer<T>::value || std::is_same<T, char8_type>::value ||
std::is_convertible<T, fmt::basic_string_view<Char>>::value ||
std::is_same<T, std_string_view<Char>>::value ||
(std::is_convertible<T, int>::value && !std::is_enum<T>::value)>>
: std::false_type {};
// Generate a unique explicit instantion in every translation unit using a tag
// type in an anonymous namespace.
namespace {
struct file_access_tag {};
} // namespace
template <class Tag, class BufType, FILE* BufType::*FileMemberPtr>
class file_access {
friend auto get_file(BufType& obj) -> FILE* { return obj.*FileMemberPtr; }
};
#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
if (auto* buf = dynamic_cast<std::filebuf*>(os.rdbuf()))
if (FILE* f = get_file(*buf)) return write_console(f, data);
#elif defined(_WIN32) && defined(__GLIBCXX__)
auto* rdbuf = os.rdbuf();
FILE* c_file;
if (auto* fbuf = dynamic_cast<__gnu_cxx::stdio_sync_filebuf<char>*>(rdbuf))
c_file = fbuf->file();
else if (auto* fbuf = dynamic_cast<__gnu_cxx::stdio_filebuf<char>*>(rdbuf))
c_file = fbuf->file();
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, data);
#endif
return false;
}
inline bool write_ostream_unicode(std::wostream&,
fmt::basic_string_view<wchar_t>) {
return false;
}
// Write the content of buf to os.
// It is a separate function rather than a part of vprint to simplify testing.
template <typename Char>
void write_buffer(std::basic_ostream<Char>& os, buffer<Char>& buf) {
const Char* buf_data = buf.data();
using unsigned_streamsize = std::make_unsigned<std::streamsize>::type;
unsigned_streamsize size = buf.size();
unsigned_streamsize max_size = to_unsigned(max_value<std::streamsize>());
do {
unsigned_streamsize n = size <= max_size ? size : max_size;
os.write(buf_data, static_cast<std::streamsize>(n));
buf_data += n;
size -= n;
} while (size != 0);
}
template <typename Char, typename T>
void format_value(buffer<Char>& buf, const T& value,
locale_ref loc = locale_ref()) {
auto&& format_buf = formatbuf<std::basic_streambuf<Char>>(buf);
auto&& output = std::basic_ostream<Char>(&format_buf);
#if !defined(FMT_STATIC_THOUSANDS_SEPARATOR)
if (loc) output.imbue(loc.get<std::locale>());
#endif
output << value;
output.exceptions(std::ios_base::failbit | std::ios_base::badbit);
}
template <typename T> struct streamed_view { const T& value; };
} // namespace detail
// Formats an object of type T that has an overloaded ostream operator<<.
template <typename Char>
struct basic_ostream_formatter : formatter<basic_string_view<Char>, Char> {
void set_debug_format() = delete;
template <typename T, typename OutputIt>
auto format(const T& value, basic_format_context<OutputIt, Char>& ctx) const
-> OutputIt {
auto buffer = basic_memory_buffer<Char>();
format_value(buffer, value, ctx.locale());
return formatter<basic_string_view<Char>, Char>::format(
{buffer.data(), buffer.size()}, ctx);
}
};
using ostream_formatter = basic_ostream_formatter<char>;
template <typename T, typename Char>
struct formatter<detail::streamed_view<T>, Char>
: basic_ostream_formatter<Char> {
template <typename OutputIt>
auto format(detail::streamed_view<T> view,
basic_format_context<OutputIt, Char>& ctx) const -> OutputIt {
return basic_ostream_formatter<Char>::format(view.value, ctx);
}
};
/**
\rst
Returns a view that formats `value` via an ostream ``operator<<``.
**Example**::
fmt::print("Current thread id: {}\n",
fmt::streamed(std::this_thread::get_id()));
\endrst
*/
template <typename T>
auto streamed(const T& value) -> detail::streamed_view<T> {
return {value};
}
namespace detail {
// Formats an object of type T that has an overloaded ostream operator<<.
template <typename T, typename Char>
struct fallback_formatter<T, Char, enable_if_t<is_streamable<T, Char>::value>>
: basic_ostream_formatter<Char> {
using basic_ostream_formatter<Char>::format;
};
inline void vprint_directly(std::ostream& os, string_view format_str,
format_args args) {
auto buffer = memory_buffer();
detail::vformat_to(buffer, format_str, args);
detail::write_buffer(os, buffer);
}
} // namespace detail
FMT_MODULE_EXPORT template <typename Char>
void vprint(std::basic_ostream<Char>& os,
basic_string_view<type_identity_t<Char>> format_str,
basic_format_args<buffer_context<type_identity_t<Char>>> args) {
auto buffer = basic_memory_buffer<Char>();
detail::vformat_to(buffer, format_str, args);
if (detail::write_ostream_unicode(os, {buffer.data(), buffer.size()})) return;
detail::write_buffer(os, buffer);
}
/**
\rst
Prints formatted data to the stream *os*.
**Example**::
fmt::print(cerr, "Don't {}!", "panic");
\endrst
*/
FMT_MODULE_EXPORT template <typename... T>
void print(std::ostream& os, format_string<T...> fmt, T&&... args) {
const auto& vargs = fmt::make_format_args(args...);
if (detail::is_utf8())
vprint(os, fmt, vargs);
else
detail::vprint_directly(os, fmt, vargs);
}
FMT_MODULE_EXPORT
template <typename... Args>
void print(std::wostream& os,
basic_format_string<wchar_t, type_identity_t<Args>...> fmt,
Args&&... args) {
vprint(os, fmt, fmt::make_format_args<buffer_context<wchar_t>>(args...));
}
FMT_END_NAMESPACE
#endif // FMT_OSTREAM_H_