construct/include/ircd/versions.h

100 lines
2.8 KiB
C++

// Matrix Construct
//
// Copyright (C) Matrix Construct Developers, Authors & Contributors
// Copyright (C) 2016-2022 Jason Volk <jason@zemos.net>
//
// Permission to use, copy, modify, and/or distribute this software for any
// purpose with or without fee is hereby granted, provided that the above
// copyright notice and this permission notice is present in all copies. The
// full license for this software is available in the LICENSE file.
#pragma once
#define HAVE_IRCD_VERSIONS_H
namespace ircd
{
struct versions;
}
/// Instances of `versions` create a dynamic version registry identifying
/// third-party dependencies throughout the project and its loaded modules.
///
/// Create a static instance of this class in a definition file or module
/// which has access to the version information of the dependency. Often there
/// can be two version identifiers for a dependency, one for headers and the
/// other for dynamically loaded shared object. In that case, create two
/// instances of this class with the same name.
///
struct ircd::versions
:instance_list<versions>
{
/// Our own name for the dependency.
string_view name;
/// Set the type to either API or ABI to indicate where this version
/// information has been sourced. Defaults to API.
enum type {API, ABI} type {API};
/// If the version number is a single (likely monotonic) integer.
long monotonic {0};
/// Alternative semantic version number.
std::array<long, 3> semantic {0};
/// Version string buffer. Copy any provided version string here.
char string[128] {0};
/// Convenience access to read the semantic version numbers.
auto &operator[](const int &idx) const;
/// Convenience access to read the monotonic integer; note that if zero
/// the semantic major number is read instead.
explicit operator const long &() const;
/// Convenience access to read the string
explicit operator string_view() const;
versions(const string_view &name,
const enum type &type = type::API,
const long &monotonic = 0,
const std::array<long, 3> &semantic = {0L},
const string_view &string = {}) noexcept;
versions(const string_view &name,
const enum type &type,
const long &monotonic,
const std::array<long, 3> &semantic,
const std::function<void (versions &, const mutable_buffer &)> &generator) noexcept;
versions() = default;
versions(versions &&) = delete;
versions(const versions &) = delete;
~versions() noexcept;
};
template<>
decltype(ircd::versions::list)
ircd::instance_list<ircd::versions>::list;
inline ircd::versions::operator
const long &()
const
{
return monotonic?: semantic[0];
}
inline ircd::versions::operator
ircd::string_view()
const
{
return string;
}
inline auto &
ircd::versions::operator[](const int &idx)
const
{
return semantic.at(idx);
}