How do I perform a circular rotation of a byte?

Question

I\'m trying to implement a function that performs a circular rotation of a byte to the left and to the right.

I wrote the same code for both operations. For example,

Answer 1

There is no rotation operator in C, but if you write:

unsigned char rotl(unsigned char c)
{
    return (c << 1) | (c >> 7);
}

then, according to this: http://www.linux-kongress.org/2009/slides/compiler_survey_felix_von_leitner.pdf (page 56), compilers will figure out what you want to do and perform the rotation it in only one (very fast) instruction.