You cannot select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
297 lines
8.9 KiB
C++
297 lines
8.9 KiB
C++
/* $Id$ */
|
|
|
|
/*
|
|
* This file is part of OpenTTD.
|
|
* OpenTTD 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, version 2.
|
|
* OpenTTD 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 OpenTTD. If not, see <http://www.gnu.org/licenses/>.
|
|
*/
|
|
|
|
/** @file pool_type.hpp Defintion of Pool, structure used to access PoolItems, and PoolItem, base structure for Vehicle, Town, and other indexed items. */
|
|
|
|
#ifndef POOL_TYPE_HPP
|
|
#define POOL_TYPE_HPP
|
|
|
|
/**
|
|
* Base class for all pools.
|
|
* @tparam Titem Type of the class/struct that is going to be pooled
|
|
* @tparam Tindex Type of the index for this pool
|
|
* @tparam Tgrowth_step Size of growths; if the pool is full increase the size by this amount
|
|
* @tparam Tmax_size Maximum size of the pool
|
|
* @tparam Tcache Whether to perform 'alloc' caching, i.e. don't actually free/malloc just reuse the memory
|
|
* @tparam Tzero Whether to zero the memory
|
|
* @warning when Tcache is enabled *all* instances of this pool's item must be of the same size.
|
|
*/
|
|
template <class Titem, typename Tindex, size_t Tgrowth_step, size_t Tmax_size, bool Tcache = false, bool Tzero = true>
|
|
struct Pool {
|
|
static const size_t MAX_SIZE = Tmax_size; ///< Make template parameter accessible from outside
|
|
|
|
const char * const name; ///< Name of this pool
|
|
|
|
size_t size; ///< Current allocated size
|
|
size_t first_free; ///< No item with index lower than this is free (doesn't say anything about this one!)
|
|
size_t first_unused; ///< This and all higher indexes are free (doesn't say anything about first_unused-1 !)
|
|
size_t items; ///< Number of used indexes (non-NULL)
|
|
|
|
bool cleaning; ///< True if cleaning pool (deleting all items)
|
|
|
|
Titem **data; ///< Pointer to array of pointers to Titem
|
|
|
|
/** Constructor */
|
|
Pool(const char *name);
|
|
/** Destroys all items in the pool and resets all member variables */
|
|
void CleanPool();
|
|
|
|
/**
|
|
* Returs Titem with given index
|
|
* @param index of item to get
|
|
* @return pointer to Titem
|
|
* @pre index < this->first_unused
|
|
*/
|
|
FORCEINLINE Titem *Get(size_t index)
|
|
{
|
|
assert(index < this->first_unused);
|
|
return this->data[index];
|
|
}
|
|
|
|
/**
|
|
* Tests whether given index can be used to get valid (non-NULL) Titem
|
|
* @param index index to examine
|
|
* @return true if PoolItem::Get(index) will return non-NULL pointer
|
|
*/
|
|
FORCEINLINE bool IsValidID(size_t index)
|
|
{
|
|
return index < this->first_unused && this->Get(index) != NULL;
|
|
}
|
|
|
|
/**
|
|
* Tests whether we can allocate 'n' items
|
|
* @param n number of items we want to allocate
|
|
* @return true if 'n' items can be allocated
|
|
*/
|
|
FORCEINLINE bool CanAllocate(size_t n = 1)
|
|
{
|
|
return this->items <= Tmax_size - n;
|
|
}
|
|
|
|
/**
|
|
* Base class for all PoolItems
|
|
* @tparam Tpool The pool this item is going to be part of
|
|
*/
|
|
template <struct Pool<Titem, Tindex, Tgrowth_step, Tmax_size, Tcache, Tzero> *Tpool>
|
|
struct PoolItem {
|
|
Tindex index; ///< Index of this pool item
|
|
|
|
/**
|
|
* Allocates space for new Titem
|
|
* @param size size of Titem
|
|
* @return pointer to allocated memory
|
|
* @note can never fail (return NULL), use CanAllocate() to check first!
|
|
*/
|
|
FORCEINLINE void *operator new(size_t size)
|
|
{
|
|
return Tpool->GetNew(size);
|
|
}
|
|
|
|
/**
|
|
* Marks Titem as free. Its memory is released
|
|
* @param p memory to free
|
|
* @note the item has to be allocated in the pool!
|
|
*/
|
|
FORCEINLINE void operator delete(void *p)
|
|
{
|
|
Titem *pn = (Titem *)p;
|
|
assert(pn == Tpool->Get(pn->index));
|
|
Tpool->FreeItem(pn->index);
|
|
}
|
|
|
|
/**
|
|
* Allocates space for new Titem with given index
|
|
* @param size size of Titem
|
|
* @param index index of item
|
|
* @return pointer to allocated memory
|
|
* @note can never fail (return NULL), use CanAllocate() to check first!
|
|
* @pre index has to be unused! Else it will crash
|
|
*/
|
|
FORCEINLINE void *operator new(size_t size, size_t index)
|
|
{
|
|
return Tpool->GetNew(size, index);
|
|
}
|
|
|
|
/**
|
|
* Allocates space for new Titem at given memory address
|
|
* @param size size of Titem
|
|
* @param ptr where are we allocating the item?
|
|
* @return pointer to allocated memory (== ptr)
|
|
* @note use of this is strongly discouraged
|
|
* @pre the memory must not be allocated in the Pool!
|
|
*/
|
|
FORCEINLINE void *operator new(size_t size, void *ptr)
|
|
{
|
|
for (size_t i = 0; i < Tpool->first_unused; i++) {
|
|
/* Don't allow creating new objects over existing.
|
|
* Even if we called the destructor and reused this memory,
|
|
* we don't know whether 'size' and size of currently allocated
|
|
* memory are the same (because of possible inheritance).
|
|
* Use { size_t index = item->index; delete item; new (index) item; }
|
|
* instead to make sure destructor is called and no memory leaks. */
|
|
assert(ptr != Tpool->data[i]);
|
|
}
|
|
return ptr;
|
|
}
|
|
|
|
|
|
/** Helper functions so we can use PoolItem::Function() instead of _poolitem_pool.Function() */
|
|
|
|
/**
|
|
* Tests whether we can allocate 'n' items
|
|
* @param n number of items we want to allocate
|
|
* @return true if 'n' items can be allocated
|
|
*/
|
|
static FORCEINLINE bool CanAllocateItem(size_t n = 1)
|
|
{
|
|
return Tpool->CanAllocate(n);
|
|
}
|
|
|
|
/**
|
|
* Returns current state of pool cleaning - yes or no
|
|
* @return true iff we are cleaning the pool now
|
|
*/
|
|
static FORCEINLINE bool CleaningPool()
|
|
{
|
|
return Tpool->cleaning;
|
|
}
|
|
|
|
/**
|
|
* Tests whether given index can be used to get valid (non-NULL) Titem
|
|
* @param index index to examine
|
|
* @return true if PoolItem::Get(index) will return non-NULL pointer
|
|
*/
|
|
static FORCEINLINE bool IsValidID(size_t index)
|
|
{
|
|
return Tpool->IsValidID(index);
|
|
}
|
|
|
|
/**
|
|
* Returs Titem with given index
|
|
* @param index of item to get
|
|
* @return pointer to Titem
|
|
* @pre index < this->first_unused
|
|
*/
|
|
static FORCEINLINE Titem *Get(size_t index)
|
|
{
|
|
return Tpool->Get(index);
|
|
}
|
|
|
|
/**
|
|
* Returs Titem with given index
|
|
* @param index of item to get
|
|
* @return pointer to Titem
|
|
* @note returns NULL for invalid index
|
|
*/
|
|
static FORCEINLINE Titem *GetIfValid(size_t index)
|
|
{
|
|
return index < Tpool->first_unused ? Tpool->Get(index) : NULL;
|
|
}
|
|
|
|
/**
|
|
* Returns first unused index. Useful when iterating over
|
|
* all pool items.
|
|
* @return first unused index
|
|
*/
|
|
static FORCEINLINE size_t GetPoolSize()
|
|
{
|
|
return Tpool->first_unused;
|
|
}
|
|
|
|
/**
|
|
* Returns number of valid items in the pool
|
|
* @return number of valid items in the pool
|
|
*/
|
|
static FORCEINLINE size_t GetNumItems()
|
|
{
|
|
return Tpool->items;
|
|
}
|
|
|
|
/**
|
|
* Dummy function called after destructor of each member.
|
|
* If you want to use it, override it in PoolItem's subclass.
|
|
* @param index index of deleted item
|
|
* @note when this function is called, PoolItem::Get(index) == NULL.
|
|
* @note it's called only when !CleaningPool()
|
|
*/
|
|
static FORCEINLINE void PostDestructor(size_t index) { }
|
|
};
|
|
|
|
private:
|
|
static const size_t NO_FREE_ITEM = MAX_UVALUE(size_t); ///< Contant to indicate we can't allocate any more items
|
|
|
|
/**
|
|
* Helper struct to cache 'freed' PoolItems so we
|
|
* do not need to allocate them again.
|
|
*/
|
|
struct AllocCache {
|
|
/** The next in our 'cache' */
|
|
AllocCache *next;
|
|
};
|
|
|
|
/** Cache of freed pointers */
|
|
AllocCache *alloc_cache;
|
|
|
|
/**
|
|
* Makes given index valid
|
|
* @param size size of item
|
|
* @param index index of item
|
|
* @pre index < this->size
|
|
* @pre this->Get(index) == NULL
|
|
*/
|
|
void *AllocateItem(size_t size, size_t index);
|
|
|
|
/**
|
|
* Resizes the pool so 'index' can be addressed
|
|
* @param index index we will allocate later
|
|
* @pre index >= this->size
|
|
* @pre index < Tmax_size
|
|
*/
|
|
void ResizeFor(size_t index);
|
|
|
|
/**
|
|
* Searches for first free index
|
|
* @return first free index, NO_FREE_ITEM on failure
|
|
*/
|
|
size_t FindFirstFree();
|
|
|
|
/**
|
|
* Allocates new item
|
|
* @param size size of item
|
|
* @return pointer to allocated item
|
|
* @note error() on failure! (no free item)
|
|
*/
|
|
void *GetNew(size_t size);
|
|
|
|
/**
|
|
* Allocates new item with given index
|
|
* @param size size of item
|
|
* @param index index of item
|
|
* @return pointer to allocated item
|
|
* @note usererror() on failure! (index out of range or already used)
|
|
*/
|
|
void *GetNew(size_t size, size_t index);
|
|
|
|
/**
|
|
* Deallocates memory used by this index and marks item as free
|
|
* @param index item to deallocate
|
|
* @pre unit is allocated (non-NULL)
|
|
* @note 'delete NULL' doesn't cause call of this function, so it is safe
|
|
*/
|
|
void FreeItem(size_t index);
|
|
};
|
|
|
|
#define FOR_ALL_ITEMS_FROM(type, iter, var, start) \
|
|
for (size_t iter = start; var = NULL, iter < type::GetPoolSize(); iter++) \
|
|
if ((var = type::Get(iter)) != NULL)
|
|
|
|
#define FOR_ALL_ITEMS(type, iter, var) FOR_ALL_ITEMS_FROM(type, iter, var, 0)
|
|
|
|
#endif /* POOL_TYPE_HPP */
|