Scott wrote:
> I have a buffer of "packed" "bytes" where each byte is less that
> 8-bits in length.
>
> This buffer is generated by capturing a bitstream (LSB first) and
> right shifting in to the LSB of a buffer.
>
> e.g. for bytes sized 7 bits, if the first byte is all ones, the second
> is all zeros, and the third is all ones,
> my buffer looks as such:
>
> 01111111
> 11000000
> xxx11111
> xxxxxxxx
> ...

OK, I understand this is what happens, but I don't understand why. Why not 
have the receiving function put them in the right order from the getgo? Is 
it because you have no control over it?


> What I would like to do is break each "byte" out of the buffer and put
> it into another buffer, e.g.
>
> 01111111
> 00000000
> 01111111
> 0xxxxxxx
> 0xxxxxxx
> ...
>
>
> I've started writing a function (in C) to do this, but I was wondering
> if anyone had anything similar (no need for me to reinvent the wheel).

They may exist, but I don't recall seeing one.


> Ideally, I was going to create a generic C function that would take as
> parameters the input and output buffer pointers, length of the input
> buffer, the size of each "byte," and where to begin processing the
> first byte (e.g. if the first bit of the first byte in the buffer was
> not at the LSB position, but somewhere in the middle, ex: bit 3:
> xxxx1xxx).

YAGNI. I would write the function to solve the problem at hand, and not 
worry about making it generic until you actually need to.

Vitaliy 

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