Re: [Qemu-devel] [PATCH] Add support for r6040 NIC

[bifferos]

--- On Wed, 31/8/11, Blue Swirl <address@hidden> wrote:

> I agree about importance of consistency, though I'd even go
> further and reformat globally. New code gets introduced 
> based on copying old code so the pain goes on.

I think this is the most important point.

I've worked on many projects where coding standards were applied, generally the 
order is:

1) Someone comes up with some new standards
2) They want to dictate the standards but are not prepared to invest any
   effort in making the existing code base conform to those standards
3) They decide it's too high risk to modify existing code
4) In conclusion they apply the coding standards to new code only
5) Some... time... passes
6) Evangelist(s) responsible for coding standards leave the team
   *or*
   Are convinced by other developers that coding standards suck
7) Repeat from 1), or drop coding standards

I've seen this pattern pretty much without fail, over the last 20 years of 
commercial software development.  You never reach the standards utopia 
unless you retrospectively change all existing code.  The only way you
ever want to do that is if you have either

a) Extensive unit tests
or 
b) Balls

Preferably both!

So what generally happens in experienced teams, is that you either 
re-work (only) the modules you touch, or you identify the coding 
standard of the module you're working on or the ones nearby and follow them.

Alternatively some developers write coding standards in a rather vague way
such that there are no hard and fast rules.  They categorise types of
problem and their severity rather than using all rules as rejection
criteria.

Couple of examples come to mind:

When developing either driver or device emulation software it's nice
to use the same identifiers as the data sheet.  By forcing everything to lower 
case it makes it harder to cross-reference things, and God forbid if the data 
sheet actually used case to distinguish registers you'd then have to invent 
identifiers to deal with it.

I looked around to see which license I could use, cribbed one from another Qemu 
file, and then promptly had to reformat it because it broke the line length 
rule, so I've reformated what was previously a standard license and crafted my 
own for no other reason that conforming with checkpatch.pl.

cheers,
Biff.