[OE-core] About pseudo's chmod

[Mark Hatle]

On 8/2/16 2:19 PM, Seebs wrote:
> On 2 Aug 2016, at 10:12, Mark Hatle wrote:
> 
>> So the problem is -- pseudo is modifying the 'original' file perms, 
>> which on a
>> new instance of the pseudo database then gets inherited.  So we get
>> unpredictable results if this is the first time through -- or not the 
>> first time
>> through.
> 
> Yeah. And the problem here is in part that we're calling chmod on a file 
> linked to a file external to pseudo, but we're also checking that file's 
> mode to find out what permissions we want it to have. Which is probably 
> an error.
> 
> So, it does look like we need the tracking, but also if we stopped 
> doing:
> 
> 	stat file1 # obtain mode
> 	ln file1 file2
> 	chmod <mode> file2
> 
> we'd save significant time AND avoid the problem.
> 
> -s
> 

The alternative to the 'ln' is a 'cp' operation.  This is how it used to work
until optimizations were added a few releases ago.  It was observed that this
saves a large amount of space -- but it had the unintended consequence of
suddenly files are now changes as the do_install/do_package processing
manipulates files and modes change...

I almost wonder if in pseudo we should avoid changing any modes internal to the
file -- until something tries to write to the file.  (Can we even capture that
and try to fix it?  If not, what we're doing is likely the only answer.)

--Mark