/**
Implementation of pure virtual function.
@see MWTCacheInterface::ReadL()
*/
void CDynamicDirCache::ReadL(TInt64 aPos, TInt aLength, TDes8& aDes)
{
#ifdef _DEBUG
if(iCacheDisabled)
{
// cache is disabled for debug purposes
__PRINT(_L("CDynamicDirCache disabled"));
User::LeaveIfError(iDrive.ReadNonCritical(aPos, aLength, aDes));
return;
}
#endif //_DEBUG
aDes.Zero();
const TUint32 PageSz = iPageSizeInBytes;//-- cache page size
TInt64 pageStartMedPos = CalcPageStartPos(aPos);
const TUint32 bytesToPageEnd = (TUint32)(pageStartMedPos + PageSz - aPos); //-- number of bytes from aPos to the end of the page
// __PRINT5(_L("CDynamicDirCache::ReadL: aPos=%lx, aLength=%x, page:%lx, pageSz:%x, bytesToPageEnd=%x"), aPos, aLength, pageStartMedPos, PageSz, bytesToPageEnd);
// if all data needed is on a single page
if((TUint32)aLength <= bytesToPageEnd)
{
ReadDataFromSinglePageL(aPos, aLength, aDes);
}
// or data to be read cross cache page boundary or probably we have more than 1 page to read
else
{
__PRINT(_L("CDynamicDirCache::ReadL() CROSS PAGE!"));
TUint32 dataLen(aLength); //-- current data length
TInt64 currMediaPos(aPos); //-- current media position
//-- 1. read data that are already in the current page
ReadDataFromSinglePageL(currMediaPos, bytesToPageEnd, aDes);
dataLen -= bytesToPageEnd;
currMediaPos += bytesToPageEnd;
TPtr8 dataNext = aDes.MidTPtr(aDes.Length());
//-- 2. read whole pages of data
while (dataLen >= PageSz)
{
//-- find out if currMediaPos is in cache. If not, find a spare page and read data there
ReadDataFromSinglePageL(currMediaPos, PageSz, dataNext);
currMediaPos += PageSz;
dataLen -= PageSz;
dataNext = dataNext.MidTPtr(dataNext.Length());
}
//-- 3. read the rest of the data
if(dataLen > 0)
{
ReadDataFromSinglePageL(currMediaPos, dataLen, dataNext);
}
} //else((TUint32)aLength <= bytesToPageEnd)
}
/**
Encode CBW into the supplied buffer. The command is also encoded using the
supplied encoding method of MClientCommandServiceReq.
@param aBuffer The buffer to copy the encoded stream in to
@param aCommand The command to be encoded into the Command Block field
*/
void TBotCbw::EncodeL(TPtr8 &aBuffer, const MClientCommandServiceReq* aCommand) const
{
__MSFNSLOG
aBuffer.SetLength(KCbwLength);
TPtr8 commandBlock = aBuffer.MidTPtr(TBotCbw::KCbwCbOffset);
aBuffer.FillZ();
TInt cbLength = aCommand->EncodeRequestL(commandBlock);
TUint8* ptr = (TUint8 *) aBuffer.Ptr();
LittleEndian::Put32(&ptr[KCbwSignatureOffset], 0x43425355);
LittleEndian::Put32(&ptr[KCbwTagOffset], iTag);
LittleEndian::Put32(&ptr[KCbwDataTransferLengthOffset], iDataTransferLength);
aBuffer[KCbwFlagOffset] = (iDirection == EDataOut) ? 0x00 : 0x80;
aBuffer[KCbwLunOffset] = iLun;
aBuffer[KCbwCbLengthOffset] = cbLength;
__BOTPRINT1(_L("BOT TBotCbw::Encode Lun=%d"), iLun);
}