LUMIERA.clone/src/lib/lifecycleregistry.hpp
Ichthyostega 7be1b7d35d Switch from TR1 preveiw to the new standard headers
- functional
- memory
- unordered collections
2014-04-03 22:42:48 +02:00

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3.5 KiB
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/*
LIFECYCLEREGISTRY.hpp - registry for application lifecycle callbacks
Copyright (C) Lumiera.org
2008, Christian Thaeter <ct@pipapo.org>
Hermann Vosseler <Ichthyostega@web.de>
This program is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License as
published by the Free Software Foundation; either version 2 of
the License, or (at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
/** @file lifecycleregistry.hpp
** Helper for registering lifecycle event callbacks, which are
** provided as a global service by lumiera::AppState. This service
** allows to enrol functions under a given label and then to call
** all those registered functions.
** @note this is in fact an event mechanism, and if we start using
** more than just this basic functionality, we should switch to
** boost::signals. (which has the downside of being an binary
** dependency).
**
** @see appstate.hpp
*/
#ifndef LUMIERA_LIFECYCLEREGISTRY_H
#define LUMIERA_LIFECYCLEREGISTRY_H
#include <map>
#include <set>
#include <string>
#include <functional>
#include <boost/scoped_ptr.hpp>
#include <boost/noncopyable.hpp>
#include "lib/util.hpp"
namespace lumiera {
using boost::scoped_ptr;
using boost::noncopyable;
using std::function;
using util::contains;
using std::string;
/**
* Registry of callback functions accessible by a label (ID)
* provided at registration. Registered functions will be added
* to a list, which can be triggered via label. Used by AppState
* to implement the lumiera lifecycle (init, shutdown) hooks.
*/
class LifecycleRegistry
: private noncopyable
{
public:
typedef void (*Hook)(void);
typedef std::set<Hook> Callbacks;
typedef Callbacks::iterator Iter;
/** @note only one copy of each distinct callback remembered */
bool enrol (Symbol label, Hook toCall)
{
return table_[label]
.insert(toCall)
.second; // true if actually stored
}
void execute (Symbol label)
{
Callbacks& cbs (table_[label]);
Iter e = cbs.end();
for (Iter p = cbs.begin();
p != e; ++p)
(*p)(); // invoke callback
}
/** get the (single) LifecycleRegistry instance.
* @warning don't use it after the end of main()! */
static LifecycleRegistry& instance() // Meyer's singleton
{
static scoped_ptr<LifecycleRegistry> theRegistry_;
if (!theRegistry_) theRegistry_.reset (new LifecycleRegistry ());
return *theRegistry_;
}
private:
std::map<Symbol, Callbacks> table_;
LifecycleRegistry () {
execute (ON_BASIC_INIT); // just to be sure, typically a NOP, because nothing is registered yet
}
~LifecycleRegistry () {}
friend void boost::checked_delete<LifecycleRegistry>(LifecycleRegistry*);
};
} // namespace lumiera
#endif