With the CHDK disassembly, especially the very first versions, where do the function names come from .. how were they worked-out ?
Many are based on strings in the firmware. I assume the rest were just made up, except in the cases where someone recognized a standard function.
Early on, there was a canon f/w upgrade (A610 or A620, if my memory serves), which contained a table with some 2000 function names and pointers. The first IDA sigs were mostly based on that (
rus. forum link). With the introduction of DryOS, the naming in the first (A720) port was probably done mostly by hand, partly based on the known VxWorks functions. The first DryOS IDA sigs were based on that port. Don't know who and how improved those sigs to their current state.