We start from the clRawFile class, which uses OS-specific memory-mapping routines to map files into the memory:
class clRawFile: public iRawFile
{
public:
RawFile() {}
virtual ~RawFile() { Close(); }The Open() member function does most of the heavy lifting. It stores physical and virtual file names, opens a file handle and creates a mapped view of the file:
bool Open( const std::string& FileName,
const std::string& VirtualFileName )
{
SetFileName( FileName );
SetVirtualFileName( VirtualFileName );
FSize = 0;
FFileData = nullptr;With Windows, we use CreateFileA() to open the file. As usual, we enclose the OS-specific parts in #ifdef blocks.:
#ifdef _WIN32
FMapFile = CreateFileA( FFileName.c_str(), GENERIC_READ,
FILE_SHARE_READ, nullptr, OPEN_EXISTING,
FILE_ATTRIBUTE_NORMAL | FILE_FLAG_RANDOM_ACCESS,
nullptr );Once the file is opened, we create a mapping object and retrieve a pointer...