From 515370b2c24511b9d999f44dffbd7a892d84a530 Mon Sep 17 00:00:00 2001
From: Jason Volk <jason@zemos.net>
Date: Thu, 22 Feb 2018 19:34:24 -0800
Subject: [PATCH] ircd::m: Add and apply module importer; replace any module
 name suffixes.

---
 include/ircd/m/import.h | 71 +++++++++++++++++++++++++++++++++++++++++
 include/ircd/m/m.h      |  2 +-
 ircd/m/m.cc             | 56 ++++++++++----------------------
 3 files changed, 88 insertions(+), 41 deletions(-)
 create mode 100644 include/ircd/m/import.h

diff --git a/include/ircd/m/import.h b/include/ircd/m/import.h
new file mode 100644
index 000000000..00b8fed9c
--- /dev/null
+++ b/include/ircd/m/import.h
@@ -0,0 +1,71 @@
+// Matrix Construct
+//
+// Copyright (C) Matrix Construct Developers, Authors & Contributors
+// Copyright (C) 2016-2018 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_M_IMPORT_H
+
+namespace ircd::m
+{
+	template<class prototype> struct import;
+
+	extern std::map<std::string, ircd::module> modules;
+}
+
+template<class prototype>
+struct ircd::m::import
+:mods::import<prototype>
+{
+	std::string modname;
+	std::string symname;
+
+	void reload();
+
+  public:
+	template<class... args> auto operator()(args&&... a);
+
+	import(std::string modname, std::string symname);
+};
+
+template<class prototype>
+ircd::m::import<prototype>::import(std::string modname,
+                                   std::string symname)
+:mods::import<prototype>{}
+,modname{std::move(modname)}
+,symname{std::move(symname)}
+{}
+
+template<class prototype>
+template<class... args>
+auto
+ircd::m::import<prototype>::operator()(args&&... a)
+{
+	if(unlikely(!*this))
+		reload();
+
+	return mods::import<prototype>::operator()(std::forward<args>(a)...);
+}
+
+template<class prototype>
+void
+ircd::m::import<prototype>::reload()
+try
+{
+	auto &import(static_cast<mods::import<prototype> &>(*this));
+	import = { modules.at(modname), symname };
+}
+catch(const std::out_of_range &e)
+{
+	throw m::UNAVAILABLE
+	{
+		"Sorry, %s in %s is currently unavailable.",
+		symname,
+		modname
+	};
+}
diff --git a/include/ircd/m/m.h b/include/ircd/m/m.h
index 0e8d8f353..1617a3bd8 100644
--- a/include/ircd/m/m.h
+++ b/include/ircd/m/m.h
@@ -20,7 +20,6 @@ namespace ircd::m
 	extern struct room my_room;
 	extern struct room control;
 	extern struct log::log log;
-	extern std::map<std::string, ircd::module> modules;
 	extern std::list<ircd::net::listener> listeners;
 
 	IRCD_OVERLOAD(generate)
@@ -45,6 +44,7 @@ namespace ircd
 
 #include "name.h"
 #include "error.h"
+#include "import.h"
 #include "id.h"
 #include "event.h"
 #include "dbs.h"
diff --git a/ircd/m/m.cc b/ircd/m/m.cc
index 07e3cfc28..32c3f2d10 100644
--- a/ircd/m/m.cc
+++ b/ircd/m/m.cc
@@ -118,7 +118,7 @@ ircd::m::init::modules()
 		if(startswith_any(name, std::begin(prefixes), std::end(prefixes)))
 			m::modules.emplace(name, name);
 
-	m::modules.emplace("root.so"s, "root.so"s);
+	m::modules.emplace("root"s, "root"s);
 }
 
 namespace ircd::m
@@ -275,20 +275,12 @@ ircd::m::create(const id::room &room_id,
                 const id::user &creator,
                 const string_view &type)
 {
-	static const auto modname
-	{
-		"client_createroom.so"
-	};
-
-	static const auto symname
-	{
-		"createroom__type"
-	};
-
 	using prototype = room (const id::room &, const id::user &, const string_view &);
-	static mods::import<prototype> function;
-	if(unlikely(!function))
-		function = { modules.at(modname), symname };
+
+	static import<prototype> function
+	{
+		"client_createroom", "createroom__type"
+	};
 
 	return function(room_id, creator, type);
 }
@@ -299,20 +291,12 @@ ircd::m::create(const id::room &room_id,
                 const id::room &parent,
                 const string_view &type)
 {
-	static const auto modname
-	{
-		"client_createroom.so"
-	};
-
-	static const auto symname
-	{
-		"createroom__parent_type"
-	};
-
 	using prototype = room (const id::room &, const id::user &, const id::room &, const string_view &);
-	static mods::import<prototype> function;
-	if(unlikely(!function))
-		function = { modules.at(modname), symname };
+
+	static import<prototype> function
+	{
+		"client_createroom", "createroom__parent_type"
+	};
 
 	return function(room_id, creator, parent, type);
 }
@@ -321,20 +305,12 @@ ircd::m::event::id::buf
 ircd::m::join(const room &room,
               const id::user &user_id)
 {
-	static const auto modname
-	{
-		"client_rooms_join.so"
-	};
-
-	static const auto symname
-	{
-		"join__room_user"
-	};
-
 	using prototype = event::id::buf (const m::room &, const id::user &);
-	static mods::import<prototype> function;
-	if(unlikely(!function))
-		function = { modules.at(modname), symname };
+
+	static import<prototype> function
+	{
+		"client_rooms", "join__room_user"
+	};
 
 	return function(room, user_id);
 }