Re: scallywag / cygport not pulling lzip

[Brian Inglis <Brian.Inglis@SystematicSw.ab.ca>]

On 2021-01-08 07:21, Jon Turney wrote:
> On 08/01/2021 13:58, Marco Atzeri via Cygwin-apps wrote:
>> On 08.01.2021 14:23, ASSI wrote:
>>> Marco Atzeri via Cygwin-apps writes:
>>>> it seems that cygport is not pulling the decompressor
>>>> that is supposed to recognise:
>>>>
>>>> https://ci.appveyor.com/project/cygwin/scallywag/builds/37134000/job/0m9h56ptrwwyg3hc 
>>>>
>>>>
>>>>>> Unpacking source flex-2.6.4.tar.lz
>>>> tar (child): lzip: Cannot exec: No such file or directory
>>>> tar (child): Error is not recoverable: exiting now
>>>> tar: Child returned status 2
>>>> tar: Error is not recoverable: exiting now
>>>> *** ERROR: tar xf flex-2.6.4.tar.lz failed
>>>
>>> Since tar is a Base package it doesn't require lzip (which would
>>> effectively make it a Base install).  You have to add lzip to
>>> BUILD_REQUIRES or switch to the GZip archive.
>>>
>>>
>>> Regards,
>>> Achim.
>>>
>>
>> Hi Achim,
>>
>> this is an upstream source package.
>>
>> IMHO cygport should pull tar and all the decompressor that
>> is supposed to manage.
>>
>>   $ grep  SRC_URI NEWS
>> ...
>>          * SRC_URI supports .tar.lz archives.
>>          * SRC_URI accepts .tar.xz archives.
>>          * SRC_URI accepts .tar.lzo archives.
>> ...
> 
> Yeah, perhaps lzip should be a dependency of cygport.

...and zstd as Achim is working on that.
I do not think we should encourage use of lower compression ratio packages in 
cygport and calm, and their libraries in setup.
It appears zstd gives up compression to gain faster decompression with less 
memory which may be advantageous for loading a kernel, but less optimal for MBs 
of base packages.

[Download size will remain significant in regions with poor or unreliable 
infrastructure, and that may include large rural populations and remote areas in 
developed countries, where achievable transfer rates and/or download limits are 
low, base data charges or overages are expensive e.g. Canada telecomm costs are 
higher than most other countries, has many areas with limited services, and 
remote communities and indigenous reservations may still have only metered 
landline/microwave service AKA long distance dialup at best, and many northern 
and western areas of Canada and the US still have little or no GSM mobile 
coverage, perhaps only legacy systems https://www.gsma.com/coverage/ ].

> For the moment, I've applied a tweak to scallywag to ensure lzip gets installed.

...and zstd also please.

Perhaps consideration should also be given to setting appropriate compression 
defaults in cygport for all supported package compressors e.g. GZIP=-9, 
XZ_OPT=-7 which does not increase the memory required from the default -6 but 
improves compression, ZSTD_CLEVEL=19 and ZSTD_NBTHREADS=`nproc` perhaps?

-- 
Take care. Thanks, Brian Inglis, Calgary, Alberta, Canada

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