VirtualMemory.cpp

[詳解]

// ----------------------------------------------------------------------------
 
#include "pch.h"
#include "VirtualMemory.h"
 
using namespace alt;
 
// VirtualMemory1 -----------------------------------------------------
 
VirtualMemory1::VirtualMemory1 ()
{
    _currentSize = 0;
}
 
LPVOID VirtualMemory1::Allocate (SIZE_T bytes, DWORD dwFlags)
{
    _currentSize = bytes;
    return ::VirtualAlloc (NULL, bytes, MEM_COMMIT | MEM_RESERVE, PAGE_READWRITE);
}
 
LPVOID VirtualMemory1::Reallocate (LPVOID lpvMem, SIZE_T bytes, DWORD dwFlags)
{
    SIZE_T previousSize = _currentSize;
    LPVOID lpvRenew = Allocate (bytes, dwFlags);
    if (lpvRenew != NULL)
    {
        CopyMemory (lpvRenew, lpvMem, previousSize);
        Free (lpvMem);
        _currentSize = bytes;
    }
 
    return lpvRenew;
}
 
BOOL VirtualMemory1::Free (LPVOID lpvMem)
{
    _currentSize = 0;
    return ::VirtualFree (lpvMem, 0, MEM_RELEASE);
}
 
// VirtualMemory -----------------------------------------------------
 
LPVOID VirtualMemory::Reserve (SIZE_T size) const
{
    return ::VirtualAlloc (NULL, size, MEM_RESERVE, PAGE_READWRITE);
}
 
BOOL VirtualMemory::Release (LPVOID lpvMem) const
{
    return ::VirtualFree (lpvMem, 0, MEM_RELEASE);
}
 
LPVOID VirtualMemory::Commit (LPVOID lpvMem, SIZE_T size) const
{
    return ::VirtualAlloc (lpvMem, size, MEM_COMMIT, PAGE_READWRITE);
}
 
BOOL VirtualMemory::Decommit (LPVOID lpvMem, SIZE_T size) const
{
#pragma warning(push)
#pragma warning(disable:6250)
    return ::VirtualFree (lpvMem, size, MEM_DECOMMIT);
#pragma warning(pop)
}
 
BOOL VirtualMemory::Lock (LPVOID lpvMem, SIZE_T size) const
{
    return ::VirtualLock (lpvMem, size);
}
 
BOOL VirtualMemory::Unlock (LPVOID lpvMem, SIZE_T size) const
{
    return ::VirtualUnlock (lpvMem, size);
}