#if defined(_MSC_VER)

#include "memory.h"

#include <Windows.h>

#include <stdexcept>

#include <cpp-utils/logging/logging.h>

using namespace cpputils::logging;

namespace cpputils {

void* UnswappableAllocator::allocate(size_t size) {

// VirtualAlloc allocates memory in full pages. This is needed, because VirtualUnlock unlocks full pages

// and might otherwise unlock unrelated memory of other allocations.

// allocate pages

void* data = ::VirtualAlloc(nullptr, size, MEM_RESERVE | MEM_COMMIT, PAGE_READWRITE);

if (nullptr == data) {

throw std::runtime_error("Error calling VirtualAlloc. Errno: " + std::to_string(GetLastError()));

}

// lock allocated pages into RAM

const BOOL success = ::VirtualLock(data, size);

if (!success) {

throw std::runtime_error("Error calling VirtualLock. Errno: " + std::to_string(GetLastError()));

}

return data;

}

void UnswappableAllocator::free(void* data, size_t size) {

// overwrite the memory with zeroes before we free it

std::memset(data, 0, size);

// unlock allocated pages from RAM

BOOL success = ::VirtualUnlock(data, size);

if (!success) {

throw std::runtime_error("Error calling VirtualUnlock. Errno: " + std::to_string(GetLastError()));

}

// free allocated pages

success = ::VirtualFree(data, 0, MEM_RELEASE);

if (!success) {

throw std::runtime_error("Error calling VirtualFree. Errno: " + std::to_string(GetLastError()));

}

}

}

#endif