Source code of the color ramp node I'm not savy with browsing Blenders source code. For another purpose I'm interested in the source code of the color ramp node.

Not the UI stuff of it, just the "math" behind it, the "take in everything, from a single number up to a complete bitmap, and remap those values according to the sliders count, color and position". 

Anyone that's into Blenders source code can help me out and post the code of the color ramp node? Or maybe directions so I can find it myself?

Thanks.
The code you're looking for is here on line 322 (the do_colorband function).

This is the definition of the node itself, and the operation is implemented here: apparently it samples a colourband texture using the input as texture coordinates.