/*
* This file is part of the DXX-Rebirth project <https://www.dxx-rebirth.com/>.
* It is copyright by its individual contributors, as recorded in the
* project's Git history. See COPYING.txt at the top level for license
* terms and a link to the Git history.
*/
#pragma once
#include <type_traits>
#include <utility>
#include "dxxsconf.h"
template <bool capture_source_location = false>
class location_wrapper
{
public:
location_wrapper() = default;
/* Allow callers to pass explicit file/line, for signature
* compatibility with `location_wrapper<true>`.
*/
location_wrapper(const char *, unsigned)
{
}
/* This must be a template to be compatible with the `scratch_buffer`
* template-typedef in `location_wrapper<true>`.
*/
template <std::size_t N>
using scratch_buffer = std::false_type;
template <std::size_t N>
static std::pair<char (&)[N], std::integral_constant<std::size_t, N>> insert_location_leader(char (&buffer)[N])
{
return {buffer, {}};
}
/* Define overloads to preserve const qualification */
static std::pair<char *, std::size_t> prepare_buffer(scratch_buffer<0> &, char *const text, const std::size_t len)
{
return {text, len};
}
static std::pair<const char *, std::size_t> prepare_buffer(scratch_buffer<0> &, const char *const text, const std::size_t len)
{
return {text, len};
}
};
#ifdef DXX_HAVE_CXX_BUILTIN_FILE_LINE
#include <cstdio>
template <>
class location_wrapper<true>
{
const char *file;
unsigned line;
public:
template <std::size_t N>
using scratch_buffer = char[N];
location_wrapper(const char *const f = __builtin_FILE(), const unsigned l = __builtin_LINE()) :
file(f), line(l)
{
}
template <std::size_t N>
std::pair<char *, std::size_t> insert_location_leader(char (&buffer)[N]) const
{
const auto written = std::snprintf(buffer, sizeof(buffer), "%s:%u: ", file, line);
return {buffer + written, sizeof(buffer) - written};
}
template <std::size_t N>
std::pair<const char *, std::size_t> prepare_buffer(char (&buffer)[N], const char *const text, const std::size_t len) const
{
const auto written = std::snprintf(buffer, sizeof(buffer), "%s:%u: %.*s", file, line, static_cast<int>(len), text);
return {buffer, len + written};
}
/* Delegate to the const-qualified version, but return a `char *` to
* match the non-const input `char *`, to preserve the choice of
* overload for the function to receive this result.
*/
template <std::size_t N>
std::pair<char *, std::size_t> prepare_buffer(char (&buffer)[N], char *const text, const std::size_t len) const
{
return {buffer, prepare_buffer(buffer, const_cast<const char *>(text), len).second};
}
};
#endif
template <typename T, bool capture_source_location = false>
class location_value_wrapper : public location_wrapper<capture_source_location>
{
T value;
public:
/* Allow callers to pass explicit file/line, for signature
* compatibility with `location_value_wrapper<T, true>`.
*/
#ifndef DXX_HAVE_CXX_BUILTIN_FILE_LINE
location_value_wrapper(const T &v) :
value(v)
{
}
#endif
location_value_wrapper(const T &v,
const char *const f
#ifdef DXX_HAVE_CXX_BUILTIN_FILE_LINE
= __builtin_FILE()
#endif
, const unsigned l
#ifdef DXX_HAVE_CXX_BUILTIN_FILE_LINE
= __builtin_LINE()
#endif
) :
location_wrapper<capture_source_location>(f, l),
value(v)
{
}
operator T() const
{
return value;
}
};