int _seek_func(void *datasource, ogg_int64_t offset, int whence)
{
MkInterfaceForDataReading* drInterface = reinterpret_cast<MkInterfaceForDataReading*>(datasource);
switch (whence)
{
case SEEK_SET:
drInterface->SetCurrentPosition(static_cast<unsigned int>(offset));
break;
case SEEK_CUR:
drInterface->SetCurrentPosition(static_cast<unsigned int>(offset) + drInterface->GetCurrentPosition());
break;
case SEEK_END:
drInterface->SetCurrentPosition(drInterface->GetEndPosition() - static_cast<unsigned int>(offset));
break;
}
return 0;
}
long _tell_func(void *datasource)
{
MkInterfaceForDataReading* drInterface = reinterpret_cast<MkInterfaceForDataReading*>(datasource);
return drInterface->GetCurrentPosition();
}
// vorbis call back
size_t _read_func(void *ptr, size_t size, size_t nmemb, void *datasource)
{
MkInterfaceForDataReading* drInterface = reinterpret_cast<MkInterfaceForDataReading*>(datasource);
size_t copySize = GetMin<size_t>(size * nmemb, drInterface->GetEndPosition() - drInterface->GetCurrentPosition());
return drInterface->Read(reinterpret_cast<unsigned char*>(ptr), copySize) ? copySize : 0;
}