[OE-core] [PATCH] sstate: Convert to use ':' as a filename sperator and use SSTATE_SWSPEC globally

[Richard Purdie]

On Fri, 2013-12-20 at 13:33 +0100, Martin Jansa wrote:
> On Fri, Dec 20, 2013 at 12:06:02PM +0000, Richard Purdie wrote:
> > Currently the code has problems differentiating between "gcc-cross" and "gcc-cross-initial"
> > sstate files. We could add in a ton of special casing but tests show this isn't scaling
> > well. Using a more unique separator resolves the issue.
> > 
> > The choice of which separator to use is a hard one. We need something which isn't commonly
> > used in PN, PV, PR, *_OS and *_ARCH which rules out '-', '_' and it needs to work ok with
> > webservers/http which makes ';' and '%' harder.
> > 
> > The change also sets SSTATE_SWSPEC globally since writing out differently named siginfo
> > files for the fetch/unpack/patch tasks is a waste of diskspace, the hashes match for
> > all PN in the majority of cases and if they don't, its not a big issue as the hash is
> > different. This makes the results from sstate debugging more understandable.
> 
> Can you mention why :: is sometimes used in SWSPEC?
> 
> I guess it's again just for easier differentianting, but maybe it should
> be mentioned in commit message.

Its so there are the same number of fields in there, its just empty for
the non-arch specific cases. 

Cheers,

Richard