Char stream

[doug4]

I have a project where I need to process large chunks of data that can be coming either from a file or from memory. I figured the easiest way to abstract this is to use a std::istream&.

This will work well for files. However, for the in-memory situation, it appears that I need to create a std::string and use the std::string to create a std::istringstream. As I read through the reference material on this site, it appears that both the construction of the std::string and std::istringstream cause the memory to be copied. I don't have numbers, yet, but based on the large amounts of data to be processed, I am concerned about the performance hit of the 2 unnecessary copies, as well as the amount of memory being consumed.

The simplest solution would be to have 2 separate functions, 1 for streams and one for uint8_t*, but that would require maintenance overhead. Is it possible to create an istream from a uint8_t* buffer without copies?

[LB]

You can easily take any old stream you want and replace its streambuffer with your own custom streambuffer. You will have to research into how to write your own streambuffer:
http://www.mr-edd.co.uk/blog/beginners_guide_streambuf

This might be overkill - I just don't know if there is already a simple answer to your question.