Re: SVN for src (was Re: Binutils 2.18 prep)

[Andrew STUBBS <andrew.stubbs@st.com>]

Daniel Jacobowitz wrote:
> On Thu, Mar 22, 2007 at 10:06:41AM +0000, Andrew STUBBS wrote:
>> We create an Subversion directory containing all the top-level files (configure 
>> etc.), but with all the subdirectories (gas, gdb etc.) present but *empty*. We 
>> then provide a script that does 'svn switch' on each directory required for a 
>> given 'module'. This is the inverse of the svn://gcc.gnu.org/svn/gcc/emptydir 
>> idea (see http://gcc.gnu.org/wiki/SvnSetup "Optimize disk usage").
> 
> You know, I think we can do this even without having to butcher the
> layout of the repository.  Check out a directory containing just the
> script, and have it use "svn switch -N" at the end to pick up the top
> level files.
> 
> I'm going to experiment.  I have a handy repository to work with :-)
> (We import CVS snapshots into svn.)

Magic, it works!

I did originally think about doing 'svn co -N src', but that makes it 
impossible to get at the subdirectories at all (another checkout works, 
but then you can't check in properly).

I hadn't though of pulling in the root via switch. Nice idea.

So we would have:

   svn co svn://sourceware.org/svn/trunk/modular-checkout src
   cd src
   ./checkout binutils

which would then do:

   svn switch svn://sourceware.org/svn/trunk/src/binutils binutils
   svn switch svn://sourceware.org/svn/trunk/src/gas gas
   ...
   svn switch -N svn://sourceware.org/svn/trunk/src .

where the last line switches in the top level files, and switches out 
the checkout script itself.

Anybody wanting to checkout *everything* still can, without jumping 
through hoops!

I suppose that, given the -N switch, it is even possible to selectively 
choose subdirectories (such as include/elf), as long as the empty 
version already exists, thus:

   svn switch -N svn://sourceware.org/svn/trunk/src/include include
   svn switch svn://sourceware.org/svn/trunk/src/include/elf \
		include/elf

I can't think of any way to select individual files.

Andrew