SuperMarioOdysseyOnline/include/sead/container/seadFreeList.h

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2022-06-16 21:33:18 +00:00
#pragma once
#include <new>
#include "basis/seadRawPrint.h"
#include "basis/seadTypes.h"
namespace sead
{
class FreeList
{
public:
void setWork(void* work, s32 elem_size, s32 num);
void reset();
void* alloc();
void free(void* ptr);
void* getFree() const { return mFree; }
void* work() const { return mWork; }
static const size_t cPtrSize = sizeof(void*);
private:
struct Node
{
Node* nextFree;
};
Node* mFree = nullptr;
void* mWork = nullptr;
};
inline void FreeList::setWork(void* work, s32 elem_size, s32 num)
{
SEAD_ASSERT(work);
SEAD_ASSERT(elem_size > 0 && elem_size % cPtrSize == 0);
SEAD_ASSERT(num > 0);
const s32 idx_multiplier = elem_size / cPtrSize;
void** const ptrs = new (work) void*[num * idx_multiplier];
mFree = new (work) Node;
// Create the linked list.
for (s32 i = 0; i < num - 1; ++i)
new (&ptrs[i * idx_multiplier]) Node{new (&ptrs[(i + 1) * idx_multiplier]) Node};
new (&ptrs[(num - 1) * idx_multiplier]) Node{nullptr};
mWork = work;
}
inline void FreeList::reset()
{
mFree = nullptr;
mWork = nullptr;
}
inline void* FreeList::alloc()
{
if (!mFree)
return nullptr;
void* ptr = mFree;
mFree = mFree->nextFree;
return ptr;
}
inline void FreeList::free(void* ptr)
{
mFree = new (ptr) Node{mFree};
}
} // namespace sead