patching source tree + converting to CVS working dir.

[Cameron, Steve]

Hi CVS folks,

Lately I've been working on linux device drivers,
and I've been searching for a way to use CVS that
doesn't involve importing the whole linux kernel tree.

I've hit upon a way that so far I like, mostly,
which is as follows:

There are several drivers I'm interested in that 
have source files under 

linux/drivers/block
linux/Documentation
linux/include/linux

I pick a kernel as a starting point, and check in
only those source files which I'm interested, and create
alias modules, one for each driver I care about, that 
lists the files associated with each driver.

Then I create a branch tag for that kernel, e.g. "k2_4_7_br"
for the 2.4.7 kernel, now, assuming I have a tag 
"k2_4_7_origin" marking the beginning of the branch,
when I get a new linux kernel, I can patch it with my
changes (or generate patch files) easily:

tar xzf linux-2.4.8.tar.gz
cvs rdiff -u -rk2_4_7_origin -rk2_4_7br linux | patch

Nothing new there.

Then, to convert this patched kernel tree into a CVS sandbox
I have to do something like:

mkdir scratch
cd scratch
cvs co -rk2_4_7_br linux
then go in and "mv" all the "CVS" directories into the 
right spots in my linux kernel tree

It would be pretty cool if I could just say instead:

tar xzf linux-2.4.8.tar.gz
cvs update -jk2_4_7_origin -rk2_4_7br linux 

and have it simultaneously patch my kernel tree
and convert it into a CVS working directory
with Entries for only those files which cvs 
already knew about. (Trying it now, it complains 
about all my files being "in the way", 
on purpose and correctly, of course.)

I'm not sure what's involved in making 
a change like this though, I haven't
looked into it too much yet.

If I were to make such a change, I guess
there would have to be an additional option 
to tell CVS to (attempt to) patch-and-CVSify 
the existing directory instead of complaining
about files that are in the way.

Does this sound like something anyone else would
be interested in, or is this a terrible idea?

-- steve