void* MemoryBlockAllocator::AllocMemory(size_t sizeOfBytes)
{
if (sizeOfBytes == 0){
return nullptr;
}
void* pResult = nullptr;
//calculate how much of blocks we need.
size_t numofRequiredblocks = (size_t)ceil((float)sizeOfBytes / (float)_blockSize);
//check whether there are enough blocks for us, index of the memory block
size_t startBit = this->_pBitfield->CheckEnoughSpaces(numofRequiredblocks);
//if have enough blocks for the memory
if (startBit != UINT_MAX)
{
//wirte the bits in bitfield
bool success = _pBitfield->WriteBits(startBit, numofRequiredblocks);
if (!success)
{
MessagedAssert(success == true, "Memory alloc failed!");
TDEBUG_PRINT_FL("Alloc failed! %d bytes of memory is too much to alloc\n", Debugger::VerbosityDebugger::LEVEL1, sizeOfBytes);
return nullptr;
}
//find the memory block which contains the address we want to return to user
size_t offset = align_get_boundry_offset(sizeof(MemoryBlock), _alignment);
MemoryBlock* pTtemp = reinterpret_cast<MemoryBlock*>(reinterpret_cast<char*>(_pBlocks)+startBit * offset);
pResult = pTtemp->GetAddress();
//record how much of blocks we alloced
pTtemp->AllocBlock(numofRequiredblocks);
TDEBUG_PRINT_FL("%d bytes = %d blocks of memory has been alloced\n", Debugger::VerbosityDebugger::LEVEL1, numofRequiredblocks*_blockSize, numofRequiredblocks);
}
else
{
MessagedAssert(startBit != UINT_MAX, "Memory alloc failed!");
TDEBUG_PRINT_FL("Alloc failed! %d bytes of memory is too much to alloc\n", Debugger::VerbosityDebugger::LEVEL1, sizeOfBytes);
}
return pResult;
}
