TnbFileLocker.h

[詳解]

#pragma once
#include "TnbHandleHandle.h"
 
 
 
//TNB Library
namespace TNB
{
 
 
 
class CFileLocker : CCopyImpossible
{
    CHandleHandle   m_hhFile;       
public:
 
    CFileLocker(void) : m_hhFile(INVALID_HANDLE_VALUE)
    {
    }
 
    ~CFileLocker(void)
    {
        Unlock();
    }
 
    bool IsLock(void) const
    {
        return ! m_hhFile.IsNull();
    }
 
    bool Lock(LPCTSTR lpszName)
    {
        Unlock();
        DWORD dwDesiredAccess = GENERIC_READ;
        DWORD dwShareMode = (FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE);
        DWORD dwCreationDisp = OPEN_EXISTING;
        m_hhFile = ::CreateFile(lpszName, dwDesiredAccess, dwShareMode, NULL, dwCreationDisp, 0, NULL);
        _GetLastError("CreateFile");
        if ( ! m_hhFile.IsNull() && ::LockFile(m_hhFile, 0, 0, DWORD_MAX, DWORD_MAX) )
        {
            return true;
        }
        m_hhFile.Null();
        return false;
    }
 
    void Unlock(void)
    {
        if ( ! m_hhFile.IsNull() )
        {
            ::UnlockFile(m_hhFile, 0, 0, DWORD_MAX, DWORD_MAX);
            m_hhFile.Null();
        }
    }
};
 
 
 
}; // TNB