Здравствуйте, я пытаюсь переписать свой собственный менеджер памяти и STL (ничего особенного, только некоторые базовые c векторные и строковые функции), и я получаю странное поведение. Я пытаюсь получить опыт в области управления памятью, потому что я учусь в старшей школе, и у меня есть свободное время. Проблема в том, что когда я создаю свою первую переменную, все идет отлично, но после создания второй переменной происходит сбой программы при создании первой переменной.
String.h /.cpp
class String {
char* pointer_toBuffer = nullptr;
size_t buffer_length = 0;
IAllocator* Allocator;
public:
String(const char* text, IAllocator* Allocator);}
String::String(const char* text, TuranAPI::MemoryManagement::IAllocator* MemoryAllocator) : Allocator(MemoryAllocator) {
std::cout << "String creation has started: " << text << std::endl;
unsigned int i = 0;
while (text[i] != 0) {
i++;
}
buffer_length = i + 1;
pointer_toBuffer = (char*)Allocator->Allocate_MemoryBlock(buffer_length * sizeof(char));//When I write the Second String part, FirstString crashes directly. I use VSDebug and it says access violation here while creating FirstString. It is successful if I delete the SecondString part.
for (unsigned int letterindex = 0; letterindex < i; letterindex++) {
pointer_toBuffer[letterindex] = text[letterindex];
}
pointer_toBuffer[i] = 0;
}
MemoryManagement.h / cpp
TAPIMemoryAllocator::TAPIMemoryAllocator(MemoryBlockInfo MemoryPool_toUse){
std::cout << "TAPIMemoryAllocator is created!\n";
std::cout << "MemoryPool's start pointer: " << MemoryPool_toUse.address << std::endl;
MemoryPool.address = MemoryPool_toUse.address;
MemoryPool.size = MemoryPool_toUse.size;
SELF = this;
}
void* TAPIMemoryAllocator::Allocate_MemoryBlock(size_t size) {
std::cout << "MemoryPool's start pointer: " << MemoryPool.address << std::endl;
std::cout << "A buffer of " << size << " bytes allocation request found in TAPIMemoryAllocator!\n";
if (SELF == nullptr) {
TMemoryManager First(1024 * 1024 * 1024 * 1);
MemoryBlockInfo FirstMemoryBlock;
FirstMemoryBlock.address = SELF->MemoryPool.address;
FirstMemoryBlock.size = size;
Allocated_MemoryBlocks[0] = FirstMemoryBlock;
return (char*)SELF->MemoryPool.address;
}
void* finaladdress = SELF->MemoryPool.address;
for (unsigned int blockindex = 0; blockindex < MAX_MEMORYBLOCKNUMBER; blockindex++) {
MemoryBlockInfo& MemoryBlock = Allocated_MemoryBlocks[blockindex];
finaladdress = (char*)finaladdress + MemoryBlock.size;
if (size <= MemoryBlock.size && MemoryBlock.address == nullptr) {
std::cout << "Intended block's size is less than found memory block!\n";
MemoryBlock.address = finaladdress;
//You shouldn't change Memory Block's size because all of the allocations before this are based upon the previous size!
//You should move all the previous allocated memory to set the size (which is not ideal!)
//If I'd want to find memory leaks causing this, I could write code here to log the leaks!
return MemoryBlock.address;
}
else if (MemoryBlock.size == 0 && MemoryBlock.address == nullptr) {
std::cout << "An empty block is created for intended block! Block's Array index is: " << blockindex << "\n";
std::cout << "MemoryPool's start pointer: " << MemoryPool.address << std::endl << "MemoryBlock's pointer: " << finaladdress << std::endl;
//This means this index in the Allocated_MemoryBlocks has never been used, so we can add the data here!
MemoryBlock.address = finaladdress;
MemoryBlock.size = size;
return MemoryBlock.address;
}
}
//If you arrive here, that means there is no empty memory block in the Allocated_MemoryBlocks array!
std::cout << "There is no empty memory block in the Allocated_MemoryBlocks array, so nullptr is returned!\n";
return nullptr;
}
TMemoryManager::TMemoryManager(size_t Main_MemoryBlockSize) {
if (SELF != nullptr) {
std::cout << "You shouldn't create a MemoryManager!";
return;
}
std::cout << "TMemoryManager is created!\n";
MainMemoryBlock.address = malloc(Main_MemoryBlockSize);
MainMemoryBlock.size = Main_MemoryBlockSize;
SELF = this;
std::cout << "Main Memory Block's start pointer: " << MainMemoryBlock.address << std::endl;
MemoryBlockInfo TuranAPI_MemoryPool;
TuranAPI_MemoryPool.address = MainMemoryBlock.address;
std::cout << "TuranAPI_MemoryPool.address: " << TuranAPI_MemoryPool.address << std::endl;
TuranAPI_MemoryPool.size = 1024 * 1024 * 10;
TAPIMemoryAllocator Create(TuranAPI_MemoryPool);
}
TMemoryManager* TMemoryManager::SELF = nullptr;
TMemoryManager First(1024 * 1024 * 1024 * 1);
Main. cpp
String FirstString("How are you?", TAPIMemoryAllocator::SELF);
std::cout << FirstString << std::endl; //If I delete the below, it prints "How are you?" as expected
String SecondString("I'm fine, thanks!", TAPIMemoryAllocator::SELF);
std::cout << SecondString << std::endl;