anotherim-desktop/plugins/windows-notification/api/include/ginvoke.hpp
2021-06-09 07:20:09 -03:00

173 lines
4.8 KiB
C++

#ifndef GINVOKE_HPP
#define GINVOKE_HPP
#include <type_traits>
#include <string>
#include <string_view>
#include <sstream>
#include <iomanip>
#include <utility>
#include <optional>
#include <variant>
#include <iterator>
#include <functional>
#include <exception>
#include <cstdint>
#include <cinttypes>
#include <glib.h>
#include "overload.hpp"
#include "make_array.hpp"
#include "hexify.hpp"
namespace glib {
namespace impl
{
using static_c_str = const char *;
using varstring_t = std::variant<std::string, static_c_str>;
struct varstring : varstring_t
{
varstring(std::string &&s) noexcept : varstring_t{std::move(s)} {}
varstring(static_c_str &&s) noexcept : varstring_t{std::move(s)} {}
varstring(std::nullptr_t) = delete;
varstring(const varstring &) = delete;
varstring(varstring &&) = default;
const char* c_str() const && = delete;
const char* c_str() const &
{
return std::visit(overload{
[](const std::string &s){ return s.c_str(); },
[](const static_c_str s){ return s; }
}, static_cast<const varstring_t &>(*this));
}
};
struct hresult
{
std::int32_t code;
varstring message;
};
std::optional<hresult> get_if_hresult_error(std::exception_ptr) noexcept;
}
template<typename OStream, typename T,
std::enable_if_t<!std::is_enum_v<T>,int> = 0>
inline auto &describe_argument(OStream &s, const T &a)
{ return s << a; }
template<typename OStream, typename T,
std::enable_if_t< std::is_enum_v<T>,int> = 0>
inline auto &describe_argument(OStream &s, const T &a)
{ return s << static_cast<std::underlying_type_t<T>>(a); }
template<typename OStream>
inline auto &describe_argument(OStream &s, std::string_view const a)
{ return s << std::quoted(a); }
template<typename OStream>
inline auto &describe_argument(OStream &s, const std::string & a)
{ return s << std::quoted(a); }
template<typename OStream>
inline auto &describe_argument(OStream &s, const char * const a)
{ return s << std::quoted(a); }
// TODO: overload for const GString *
// not implemented (TODO maybe):
template<typename OStream>
inline auto &describe_argument(OStream &s, std::wstring_view const a) = delete;
template<typename OStream>
inline auto &describe_argument(OStream &s, const std::wstring & a) = delete;
template<typename OStream>
inline auto &describe_argument(OStream &s, const wchar_t * const a) = delete;
inline impl::varstring describe_arguments() noexcept { return {""}; }
template<typename... Arg>
inline impl::varstring describe_arguments(const Arg &... a) noexcept try
{
std::ostringstream ss;
((describe_argument(ss,a) << ','), ...);
auto s = std::move(ss).str();
s.pop_back();
return {std::move(s)};
}
catch (...)
{
return {"<failed to stringify arguments>"};
}
#define FORMAT "%s(%s) failed: %s"
template<typename... Arg>
inline void log_invocation_failure(const char *e,
const char *func_name, const Arg &... a) noexcept
{
const auto args = describe_arguments(a...);
g_warning(FORMAT, func_name, args.c_str(), e);
}
template<typename... Arg>
inline void log_invocation_failure_desc(const char *e, const char *e_desc,
const char *func_name, const Arg &... a) noexcept
{
const auto args = describe_arguments(a...);
g_warning(FORMAT": %s", func_name, args.c_str(), e, e_desc);
}
#undef FORMAT
struct regular_void {};
template<typename Invokable, typename... Arg>
inline auto invoke(Invokable &&i, const Arg &... a)
{
using R = decltype(std::invoke(std::forward<Invokable>(i), a...));
if constexpr (std::is_void_v<R>)
{
std::invoke(std::forward<Invokable>(i), a...);
return regular_void{};
}
else
return std::invoke(std::forward<Invokable>(i), a...);
}
template<typename Invokable, typename... Arg>
inline auto try_invoke(
const char *func_name, Invokable &&i, const Arg &... a) noexcept
-> std::optional<decltype(invoke(std::forward<Invokable>(i), a...))>
try
{
return invoke(std::forward<Invokable>(i), a...);
}
catch (const std::exception &e)
{
log_invocation_failure(e.what(), func_name, a...);
return {};
}
catch (...)
{
if (const auto e = impl::get_if_hresult_error(std::current_exception()))
{
auto hr = make_array("hresult 0x01234567\0");
hexify32(static_cast<std::uint32_t>(e->code), std::end(hr)-1);
log_invocation_failure_desc(
std::begin(hr), e->message.c_str(), func_name, a...);
}
else
log_invocation_failure("unknown error", func_name, a...);
return {};
}
} // namespace glib
#define g_try_invoke(invokable, ...) \
glib::try_invoke(#invokable, invokable, __VA_ARGS__)
#define g_try_invoke0(invokable) \
glib::try_invoke(#invokable, invokable)
#endif