ircd::stats: Start a preliminary stats system.

include/ircd/ircd.h

@@ -45,6 +45,7 @@
 #include "http.h"
 #include "magics.h"
 #include "conf.h"
+#include "stats.h"
 #include "fs/fs.h"
 #include "ios.h"
 #include "ctx/ctx.h"

include/ircd/stats.h

@@ -0,0 +1,40 @@
+// Matrix Construct
+//
+// Copyright (C) Matrix Construct Developers, Authors & Contributors
+// Copyright (C) 2016-2019 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_STATS_H
+
+namespace ircd::stats
+{
+	struct item;
+
+	IRCD_EXCEPTION(ircd::error, error)
+	IRCD_EXCEPTION(error, not_found)
+
+	extern std::map<string_view, item *> items;
+}
+
+struct ircd::stats::item
+{
+	using callback = std::function<string_view (const mutable_buffer &)>;
+
+	static const size_t NAME_MAX_LEN;
+
+	json::strung feature_;
+	json::object feature;
+	string_view name;
+	callback cb;
+
+  public:
+	item(const json::members &, callback);
+	item(item &&) = delete;
+	item(const item &) = delete;
+	~item() noexcept;
+};

ircd/Makefile.am

@@ -110,6 +110,7 @@ libircd_la_SOURCES =   \
 	json.cc            \
 	locale.cc          \
 	conf.cc            \
+	stats.cc           \
 	logger.cc          \
 	sodium.cc          \
 	rfc1459.cc         \

ircd/stats.cc

@@ -0,0 +1,69 @@
+// Matrix Construct
+//
+// Copyright (C) Matrix Construct Developers, Authors & Contributors
+// Copyright (C) 2016-2019 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.
+
+decltype(ircd::stats::items)
+ircd::stats::items
+{};
+
+//
+// item
+//
+
+decltype(ircd::stats::item::NAME_MAX_LEN)
+ircd::stats::item::NAME_MAX_LEN
+{
+	127
+};
+
+ircd::stats::item::item(const json::members &opts,
+                        callback cb)
+:feature_
+{
+	opts
+}
+,feature
+{
+	feature_
+}
+,name
+{
+	unquote(feature.at("name"))
+}
+,cb
+{
+	std::move(cb)
+}
+{
+	if(name.size() > NAME_MAX_LEN)
+		throw error
+		{
+			"Stats item '%s' name length:%zu exceeds max:%zu",
+			name,
+			name.size(),
+			NAME_MAX_LEN
+		};
+
+	if(!items.emplace(name, this).second)
+		throw error
+		{
+			"Conf item named '%s' already exists", name
+		};
+}
+
+ircd::stats::item::~item()
+noexcept
+{
+	if(name)
+	{
+		const auto it{items.find(name)};
+		assert(data(it->first) == data(name));
+		items.erase(it);
+	}
+}