Cog/Frameworks/OpenMPT/OpenMPT/common/mptStringFormat.h
Christopher Snowhill 9d3089462e
Updated libOpenMPT to version 0.7
Signed-off-by: Christopher Snowhill <kode54@gmail.com>
2023-05-04 18:23:25 -07:00

173 lines
6.9 KiB
C++

/*
* mptStringFormat.h
* -----------------
* Purpose: Convert other types to strings.
* Notes : Currently none.
* Authors: OpenMPT Devs
* The OpenMPT source code is released under the BSD license. Read LICENSE for more details.
*/
#pragma once
#include "openmpt/all/BuildSettings.hpp"
#include "mpt/base/detect.hpp"
#include "mpt/endian/integer.hpp"
#include "mpt/format/default_formatter.hpp"
#include "mpt/format/message.hpp"
#include "mpt/format/message_macros.hpp"
#include "mpt/format/simple.hpp"
#include "mpt/format/simple_spec.hpp"
#include "mpt/string/types.hpp"
#include "mpt/string_transcode/transcode.hpp"
#include "openmpt/base/FlagSet.hpp"
#include "mptString.h"
#include <cstddef>
// The following section demands a rationale.
// 1. mpt::afmt::val(), mpt::wfmt::val() and mpt::ufmt::val() mimic the semantics of c++11 std::to_string() and std::to_wstring().
// There is an important difference though. The c++11 versions are specified in terms of sprintf formatting which in turn
// depends on the current C locale. This renders these functions unusable in a library context because the current
// C locale is set by the library-using application and could be anything. There is no way a library can get reliable semantics
// out of these functions. It is thus better to just avoid them.
// ToAString() and ToWString() are based on iostream internally, but the the locale of the stream is forced to std::locale::classic(),
// which results in "C" ASCII locale behavior.
// 2. The full suite of printf-like or iostream like number formatting is generally not required. Instead, a sane subset functionality
// is provided here.
// When formatting integers, it is recommended to use mpt::afmt::dec or mpt::afmt::hex. Appending a template argument '<n>' sets the width,
// the same way as '%nd' would do. Appending a '0' to the function name causes zero-filling as print-like '%0nd' would do. Spelling 'HEX'
// in upper-case generates upper-case hex digits. If these are not known at compile-time, a more verbose FormatValA(int, format) can be
// used.
// 3. mpt::format(format)(...) provides simplified and type-safe message and localization string formatting.
// The only specifier allowed is '{}' enclosing a number n. It references to n-th parameter after the format string (1-based).
// This mimics the behaviour of QString::arg() in QT4/5 or MFC AfxFormatString2(). C printf-like functions offer similar functionality
// with a '%n$TYPE' syntax. In .NET, the syntax is '{n}'. This is useful to support localization strings that can change the parameter
// ordering.
// 4. Every function is available for std::string, std::wstring and mpt::ustring. std::string makes no assumption about the encoding, which
// basically means, it should work for any 7-bit or 8-bit encoding, including for example ASCII, UTF8 or the current locale encoding.
// std::string std::wstring mpt::ustring mpt::tsrtring CString
// mpt::afmt mpt::wfmt mpt::ufmt mpt::tfmt mpt::cfmt
// MPT_AFORMAT("{}") MPT_WFORMAT("{}") MPT_UFORMAT("{}") MPT_TFORMAT("{}") MPT_CFORMAT("{}")
// 5. All functionality here delegates real work outside of the header file so that <sstream> and <locale> do not need to be included when
// using this functionality.
// Advantages:
// - Avoids binary code bloat when too much of iostream operator << gets inlined at every usage site.
// - Faster compile times because <sstream> and <locale> (2 very complex headers) are not included everywhere.
// Disadvantages:
// - Slightly more c++ code is required for delegating work.
// - As the header does not use iostreams, custom types need to overload mpt::UString instead of iostream operator << to allow for custom type
// formatting.
// - std::string, std::wstring and mpt::ustring are returned from somewhat deep cascades of helper functions. Where possible, code is
// written in such a way that return-value-optimization (RVO) or named-return-value-optimization (NRVO) should be able to eliminate
// almost all these copies. This should not be a problem for any decent modern compiler (and even less so for a c++11 compiler where
// move-semantics will kick in if RVO/NRVO fails).
namespace mpt {
inline namespace MPT_INLINE_NS {
template <typename Tstring, typename Tint, mpt::endian endian>
inline auto format_value_default(const mpt::packed<Tint, endian> & x) -> decltype(mpt::default_formatter::format<Tstring, Tint>(x)) {
return mpt::default_formatter::format<Tstring, Tint>(x);
}
} // namespace MPT_INLINE_NS
} // namespace mpt
OPENMPT_NAMESPACE_BEGIN
template <typename Tstring, typename T>
inline auto format_value_default(const T & x) -> decltype(mpt::transcode<Tstring>(x.ToUString())) {
return mpt::transcode<Tstring>(x.ToUString());
}
template <typename Tstring, typename T>
inline auto format_value_default(const T & x) -> decltype(mpt::transcode<Tstring>(ToUString(x))) {
return mpt::transcode<Tstring>(ToUString(x));
}
namespace mpt
{
template <typename Tstring, typename T>
inline auto format_value_default(const T & x) -> decltype(mpt::transcode<Tstring>(x.ToUString())) {
return mpt::transcode<Tstring>(x.ToUString());
}
template <typename Tstring, typename T>
inline auto format_value_default(const T & x) -> decltype(mpt::transcode<Tstring>(ToUString(x))) {
return mpt::transcode<Tstring>(ToUString(x));
}
template <typename Tstring>
using fmtT = mpt::format<Tstring>;
using afmt = fmtT<std::string>;
#if !defined(MPT_COMPILER_QUIRK_NO_WCHAR)
using wfmt = fmtT<std::wstring>;
#endif
using ufmt = fmtT<mpt::ustring>;
#if defined(MPT_ENABLE_CHARSET_LOCALE)
using lfmt = fmtT<mpt::lstring>;
#endif // MPT_ENABLE_CHARSET_LOCALE
#if MPT_OS_WINDOWS
using tfmt = fmtT<mpt::tstring>;
#endif
#if defined(MPT_WITH_MFC)
using cfmt = fmtT<CString>;
#endif // MPT_WITH_MFC
#define MPT_AFORMAT(f) MPT_AFORMAT_MESSAGE(f)
#if !defined(MPT_COMPILER_QUIRK_NO_WCHAR)
#define MPT_WFORMAT(f) MPT_WFORMAT_MESSAGE(f)
#endif
#define MPT_UFORMAT(f) MPT_UFORMAT_MESSAGE(f)
#if defined(MPT_ENABLE_CHARSET_LOCALE)
#define MPT_LFORMAT(f) MPT_LFORMAT_MESSAGE(f)
#endif // MPT_ENABLE_CHARSET_LOCALE
#if MPT_OS_WINDOWS
#define MPT_TFORMAT(f) MPT_TFORMAT_MESSAGE(f)
#endif // MPT_OS_WINDOWS
#if defined(MPT_WITH_MFC)
#define MPT_CFORMAT(f) MPT_CFORMAT_MESSAGE(f)
#endif // MPT_WITH_MFC
} // namespace mpt
template <typename enum_t, typename store_t>
mpt::ustring ToUString(FlagSet<enum_t, store_t> flagset)
{
mpt::ustring str(flagset.size_bits(), UC_('0'));
for(std::size_t x = 0; x < flagset.size_bits(); ++x)
{
str[flagset.size_bits() - x - 1] = (flagset.value().as_bits() & (static_cast<typename FlagSet<enum_t>::store_type>(1) << x) ? UC_('1') : UC_('0'));
}
return str;
}
OPENMPT_NAMESPACE_END