#pragma once
class MemoryBlock
{
private:
 void* p_rawMem;
 void* p_currentMemLocation;
 size_t p_currentMemLocationOffset;
 size_t p_totalMemSize;
 size_t p_remainingMemSize;
 size_t p_alignment;
 void p_addCurrentMemLocation(size_t delta);
public:
 MemoryBlock(size_t size, size_t alignment);
 void* getMemoryWith(size_t size, size_t alignemnt);
 ~MemoryBlock();
};

#include <memory>
#include <stdexcept>
#include <cmath>
#include <assert.h>
#include "MemoryBlock.h"
void MemoryBlock::p_addCurrentMemLocation(size_t delta)
{
 if (delta == 0) {
 return;
 }
 p_currentMemLocationOffset += delta;
 assert((p_currentMemLocationOffset) <= p_totalMemSize);
 p_remainingMemSize -= delta;
 if (p_remainingMemSize == 0) {
 p_currentMemLocation = p_lastMemByteLocation;
 }
 else {
 p_currentMemLocation = static_cast<void*>(static_cast<char*>(p_currentMemLocation) + delta);
 }
}
MemoryBlock::MemoryBlock(size_t size, size_t alignment):
 p_rawMem(_aligned_malloc(size, alignment)),
 p_currentMemLocation(p_rawMem),
 p_currentMemLocationOffset(0),
 p_totalMemSize(size),
 p_remainingMemSize(size),
 p_alignment(alignment)
{
}
void* MemoryBlock::getMemoryWith(size_t size, size_t alignment)
{
 if (size > p_totalMemSize) {
 throw std::bad_alloc();
 }
 if (size == 0) {
 throw std::invalid_argument("size must be greater than 0");
 }
 if (alignment == 0 || (alignment &(alignment-1))!= 0) {//checks it alignment is power of 2
 throw std::invalid_argument("alignment should be a power of 2.");
 }
 if (alignment > p_alignment) {
 throw std::invalid_argument("alignment requirement is greater than the memory block alignment.");
 }
 if (size > p_remainingMemSize) {
 return nullptr;
 }
 if (p_totalMemSize == p_remainingMemSize) {
 p_addCurrentMemLocation(size);
 return p_rawMem;
 }
 p_addCurrentMemLocation((std::ceil(p_currentMemLocationOffset/(double)alignment)*alignment)-p_currentMemLocationOffset);
 void* retVal = p_currentMemLocation;
 p_addCurrentMemLocation(size);
 return retVal;
}
MemoryBlock::~MemoryBlock()
{
 _aligned_free(p_rawMem);
}

#pragma once
class MemoryBlock
{
private:
 void* p_rawMem;
 void* p_currentMemLocation;
 size_t p_currentMemLocationOffset;
 size_t p_totalMemSize;
 size_t p_remainingMemSize;
 size_t p_alignment;
 void *p_lastMemByteLocation;
 void p_addCurrentMemLocation(size_t delta);
public:
 MemoryBlock(size_t size, size_t alignment);
 void* getMemoryWith(size_t size, size_t alignemnt);
 ~MemoryBlock();
};

#include <memory>
#include <stdexcept>
#include <cmath>
#include <assert.h>
#include "MemoryBlock.h"
void MemoryBlock::p_addCurrentMemLocation(size_t delta)
{
 if (delta == 0) {
 return;
 }
 p_currentMemLocationOffset += delta;
 assert((p_currentMemLocationOffset) <= p_totalMemSize);
 p_remainingMemSize -= delta;
 if (p_remainingMemSize == 0) {
 p_currentMemLocation = p_lastMemByteLocation;
 }
 else {
 p_currentMemLocation = static_cast<void*>(static_cast<char*>(p_currentMemLocation) + delta);
 }
}
MemoryBlock::MemoryBlock(size_t size, size_t alignment):
 p_rawMem(_aligned_malloc(size, alignment)),
 p_currentMemLocation(p_rawMem),
 p_currentMemLocationOffset(0),
 p_totalMemSize(size),
 p_remainingMemSize(size),
 p_alignment(alignment),
 p_lastMemByteLocation(static_cast<void*>(static_cast<char*>(p_rawMem) + (size - 1)))
{
}
void* MemoryBlock::getMemoryWith(size_t size, size_t alignment)
{
 if (size > p_totalMemSize) {
 throw std::bad_alloc();
 }
 if (size == 0) {
 throw std::invalid_argument("size must be greater than 0");
 }
 if (alignment == 0 || (alignment &(alignment-1))!= 0) {//checks it alignment is power of 2
 throw std::invalid_argument("alignment should be a power of 2.");
 }
 if (alignment > p_alignment) {
 throw std::invalid_argument("alignment requirement is greater than the memory block alignment.");
 }
 if (size > p_remainingMemSize) {
 return nullptr;
 }
 if (p_totalMemSize == p_remainingMemSize) {
 p_addCurrentMemLocation(size);
 return p_rawMem;
 }
 p_addCurrentMemLocation((std::ceil(p_currentMemLocationOffset/(double)alignment)*alignment)-p_currentMemLocationOffset);
 void* retVal = p_currentMemLocation;
 p_addCurrentMemLocation(size);
 return retVal;
}
MemoryBlock::~MemoryBlock()
{
 _aligned_free(p_rawMem);
}

programmed in visual studio 2019 with c++17 feature set.

MemoryBlock.h

MemoryBlock.cpp

main.cpp

I also ask you if the usage of the code is correct in the main function, and if Im handling the void pointers adequately in both single-variable and array cases. If not, of course, please correct me with an explanation. say if im doing main, specifically, correctly or the whole thing- and if not make it clear why. Also suggest if I should be using an underlying memory buffer of char* instead of void*(perhaps combined with static arrays).

This is programmed in Visual Studio 2019 with the C++17 feature set.

MemoryBlock.h

MemoryBlock.cpp

main.cpp

I also ask you if the usage of the code is correct in the main function, and if I'm handling the void pointers adequately in both single-variable and array cases. If not, of course, please correct me with an explanation. Say if I'm doing main, specifically, correctly or the whole thing- and if not, make it clear why. Also suggest if I should be using an underlying memory buffer of char* instead of void*(perhaps combined with static arrays).