LUMIERA.clone/src/lib/allocation-cluster.hpp

281 lines
7.9 KiB
C++

/*
ALLOCATION-CLUSTER.hpp - allocating and owning a pile of objects
Copyright (C) Lumiera.org
2008, 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 allocation-cluster.hpp
** Memory management for the low-level model (render nodes network).
** The model is organised into temporal segments, which are considered
** to be structurally constant and uniform. The objects within each
** segment are strongly interconnected, and thus each segment is
** being built in a single build process and is replaced or released
** as a whole. AllocationCluster implements memory management to
** support this usage pattern.
**
** @note this file is organised in a way which doesn't bind the
** client code to the memory manager implementation. Parts of the
** interface depending on the usage situation are implemented using
** templates, and thus need to be in the header. This way they can
** exploit the type information available in call context. This
** information is passed to generic implementation functions
** defined in allocation-cluster.cpp . In a similar vein, the
** AllocationCluster::MemoryManger is just forward declared.
**
** @see allocation-cluster-test.cpp
** @see builder::ToolFactory
** @see frameid.hpp
*/
#ifndef LIB_ALLOCATION_CLUSTER_H
#define LIB_ALLOCATION_CLUSTER_H
#include <vector>
#include <boost/scoped_ptr.hpp>
#include <boost/noncopyable.hpp>
#include "lib/error.hpp"
#include "lib/sync-classlock.hpp"
#include "lib/scoped-holder.hpp"
#include "lib/scoped-holder-transfer.hpp"
namespace lib {
using boost::scoped_ptr;
/**
* A pile of objects sharing common allocation and lifecycle.
* AllocationCluster owns a number of object families of various types.
* Each of those contains a initially undetermined (but rather large)
* number of individual objects, which can be expected to be allocated
* within a short timespan and which are to be released cleanly on
* destruction of the AllocationCluster. We provide a service creating
* individual objects with arbitrary ctor parameters.
* @warning make sure the objects dtors aren't called and object references
* aren't used after shutting down a given AllocationCluster.
* @todo implement a facility to control the oder in which
* the object families are to be discarded. Currently
* they are just purged in reverse order defined by
* the first request for allocating a certain type.
* @todo should we use an per-instance lock? We can't avoid
* the class-wide lock, unless also the type-ID registration
* is done on a per-instance base. AllocationCluster is intended
* to be used within the builder, which executes in a dedicated
* thread. Thus I doubt lock contention could be a problem and
* we can avoid using a mutex per instance. Re-evaluate this!
*/
class AllocationCluster
: boost::noncopyable
{
public:
AllocationCluster ();
~AllocationCluster () throw();
template<class TY>
TY&
create ()
{
TY* obj = new(allocation<TY>()) TY();
return commit(obj);
}
template<class TY, typename P0>
TY&
create (P0& p0)
{
TY* obj = new(allocation<TY>()) TY (p0);
return commit(obj);
}
template<class TY, typename P0, typename P1>
TY&
create (P0& p0, P1& p1)
{
TY* obj = new(allocation<TY>()) TY (p0,p1);
return commit(obj);
}
template<class TY, typename P0, typename P1, typename P2>
TY&
create (P0& p0, P1& p1, P2& p2)
{
TY* obj = new(allocation<TY>()) TY (p0,p1,p2);
return commit(obj);
}
template<class TY, typename P0, typename P1, typename P2, typename P3>
TY&
create (P0& p0, P1& p1, P2& p2, P3& p3)
{
TY* obj = new(allocation<TY>()) TY (p0,p1,p2,p3);
return commit(obj);
}
private:
/** initiate an allocation for the given type */
template<class TY>
void*
allocation();
/** finish the allocation after the ctor is successful */
template<class TY>
TY&
commit (TY* obj);
/**
* The type-specific configuration information
* any low-level memory manager needs to know
*/
struct TypeInfo;
/**
* low-level memory manager responsible for
* the allocations of one specific type.
*/
class MemoryManager;
/**
* organising the association Type -> table entry
*/
template<class TY>
struct TypeSlot;
static size_t maxTypeIDs;
typedef ScopedPtrHolder<MemoryManager> HMemManager;
typedef Allocator_TransferNoncopyable<HMemManager> Allo;
typedef std::vector<HMemManager,Allo> ManagerTable;
ManagerTable typeHandlers_; ///< table of active MemoryManager instances
HMemManager&
handler (size_t slot)
{
ASSERT (0<slot && slot<=typeHandlers_.size());
return typeHandlers_[slot-1];
}
/** implementation of the actual memory allocation
* is pushed down to the MemoryManager impl. */
void* initiateAlloc (size_t& slot);
void* initiateAlloc (TypeInfo type, size_t& slot);
/** enrol the allocation after successful ctor call */
void finishAlloc (size_t& slot, void*);
};
//-----implementation-details------------------------
struct AllocationCluster::TypeInfo
{
size_t allocSize;
void (*killIt)(void*); ///< deleter function
template<class TY>
TypeInfo(TY*)
: allocSize(sizeof(TY)),
killIt(&TypeSlot<TY>::kill)
{ }
TypeInfo() ///< denotes "unknown" type
: allocSize(0),
killIt(0)
{ }
};
template<class TY>
struct AllocationCluster::TypeSlot
{
static size_t id_; ///< table pos+1 of the memory manager in charge for type TY
static size_t &
get()
{
return id_;
}
static TypeInfo
setup()
{
ClassLock<AllocationCluster> guard();
if (!id_)
id_= ++maxTypeIDs;
return TypeInfo ((TY*) 0 );
}
static void
kill (void* obj)
{
TY* p = static_cast<TY*>(obj);
ASSERT (p);
ASSERT (INSTANCEOF (TY,p));
p->~TY();
}
};
/** storage for static bookkeeping of type allocation slots */
template<class TY>
size_t AllocationCluster::TypeSlot<TY>::id_;
template<class TY>
inline void*
AllocationCluster::allocation()
{
void *mem = initiateAlloc (TypeSlot<TY>::get());
if (!mem)
mem = initiateAlloc (TypeSlot<TY>::setup(),TypeSlot<TY>::get());
ENSURE (mem);
return mem;
}
template<class TY>
inline TY&
AllocationCluster::commit (TY* obj)
{
REQUIRE (obj);
finishAlloc (TypeSlot<TY>::get(), obj);
return *obj;
}
} // namespace lib
#endif