Planned setup.ini changes for early 2018

[Peter A. Castro]

On Fri, 12 Jan 2018, Jon Turney wrote:
> On 11/01/2018 17:53, Peter A. Castro wrote:
>> On Wed, 10 Jan 2018, Jon Turney wrote:
>>> * Add depends: to version descriptions
>>> 
>>> This is a version-specific list of required packages (as opposed to 
>>> requires:, which is per-package, and contains the union of the 
>>> dependencies for all versions).
>>> 
>>> I believe that historical setup versions will either ignore, or can handle 
>>> depends: (just containing package names, without version relations) 
>>> relatively sanely (see [1] et seq. for details).
>> 
>> As long as the behaviour you outline in [1] is consistent, then that means 
>> I should be able to use older Setup with newer setup.ini, yes?  That will 
>> be useful for people who use the Time Machine. :)
>
> Yes, this doesn't break backwards compatibility.

Excellent!

> I'm not sure what reasons there are to use older setup on a circa from after 
> the date of this change.

It's not quite as strange as you might think.  Older environments can't 
necessary run newer Setup (winXP anyone? :), but, on occasion, need some 
package from a later circa that's associated with a newer, but 
incompatable, Setup version.  Yes, yes, I know, "don't do that".  Caveat 
emptor and all that.

> I hope this means that the time machine can/will preserve depends: lines.

It does.  'setup.ini' is preserved as originally distributed from 
cygwin.com (and, of course, it's mirrors).

>>> * De-duplicate source archives
>>> 
>>> Source archives which are identical[2] between x86 and x86_64 will be 
>>> moved to paths starting src/ in the release area.
>> 
>> I'm not quite visualizing this,  Do you mean there will be a new directory 
>> name 'src' that will be on the same level as 'x86' and 'x86_64' or will it 
>> be higher up the directory tree?  It matters to me 
>
> This means src/ on the same level as x86/ x86_64/ and noarch/.

Thanks for the confirmation.  I'll need to make some adjustments to the 
Time Machine for this, but should be trivial.  Do you have a schedule of 
when you will start pushing this change out?

>> for the Time Machine as I'll need to be able to re-create the same 
>> directory hierarchy for each circa.  It's a selectively automated process 
>> currently, but I need to know what symlink to place where.  :)
>> 
>>> Doing post-hoc de-duplication is unfortunate, but worthwhile given the 
>>> potential size saving in mirrors (see [3] et seq.), until cygport can be 
>>> taught how to make suitable source packages (which has several unresolved 
>>> issues, also discussed at [3], [4] et seq.).
>> 
>> Will this be done en masse upon the next setup.ini build cycle, or over 
>> time as each new package is updated?  Having a massive amount of "new" 
>> packages show up under a "new" directory named 'src' will be quite a lot 
>> for the mirrors to absorb all at once.  For the Time Machine it might 
>> effectively be double as I have to maintain the old hierarchy as well as 
>> the new one (under the assumption that you'd apply the de-duplication 
>> retroactively).
>
> The process will be gradual and retroactive.

Ok.  Thanks for confirming.  I'll watch for a mighty "gulp" in my pull 
logs. :)

> I'm not quite sure yet how it's going to apply to new uploads.  Often x86 and 
> x86_64 packages are uploaded separately, so either it happens asynchronously, 
> after the last upload of the pair has been accepted, or I defer accepting and 
> deduping the upload until both are uploaded.

What of cases where the version for x86 and x86_64 uploaded aren't the 
same (it happens)?  Will those be skipped or am I misunderstanding how 
this dedup process will work?

Anyway, thanks for the awesome effort to improve distribution of Cygwin.

-- 
--=> Peter A. Castro
Email: doctor at fruitbat dot org / Peter dot Castro at oracle dot com
 	"Cats are just autistic Dogs" -- Dr. Tony Attwood