[pacman-dev] [PATCH] pacman: don't nuke local repos with -Sc

[Allan McRae]

On 24/6/21 10:48 pm, Morgan Adamiec wrote:
> 
> 
> On 24/06/2021 13:31, Andrew Gregory wrote:
>> On 06/24/21 at 12:58pm, Morgan Adamiec wrote:
>>>
>>>
>>> On 24/06/2021 12:51, Allan McRae wrote:
>>>> On 24/6/21 9:33 pm, Morgan Adamiec wrote:
>>>>>
>>>>>
>>>>> On 24/06/2021 09:25, Allan McRae wrote:
>>>>>> On 24/6/21 6:19 pm, Morgan Adamiec wrote:
>>>>>>>
>>>>>>>
>>>>>>> On 24/06/2021 06:38, Allan McRae wrote:
>>>>>>>> On 15/6/21 5:11 am, morganamilo wrote:
>>>>>>>>> When using a local repo as a cachedir  pacman -Scc or pacman -Sc
>>>>>>>>> without KeepCurrent will delete the repo database and packages
>>>>>>>>> resulting in a lost database and non functional pacman.
>>>>>>>>>
>>>>>>>>> So special case file:/// repos in cache to not get nuked and foce
>>>>>>>>> KeepCurrent on.
>>>>>>>>> ---
>>>>>>>>
>>>>>>>> This behaviour change is undocumented.
>>>>>>>>
>>>>>>>> I don't think we should do this for -Scc.  That is explicitly asking all
>>>>>>>> package files in cache directories to be removed, so that is what you get.
>>>>>>>>
>>>>>>>> I also am leaning towards this behaviour for -Sc being unexpected (even
>>>>>>>> if documented).  Pacman's job is really not to manage complex cache
>>>>>>>> set-ups and I'm not convinced this should be supported.
>>>>>>>>
>>>>>>>> Allan
>>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>> I want this to go ahead, especially with -Scc. Otherwise -Scc can end up
>>>>>>> losing you your .db file, breaking pacman, the local repo's .db and all
>>>>>>> the build packages.
>>>>>>>
>>>>>>> This use case is not complex in my opinion. It's just adding one line to
>>>>>>> your pacman.conf to stop every single package being duplicated.
>>>>>>>
>>>>>>> If you're still against this do you have any alternative solutions in
>>>>>>> mind to handle this?
>>>>>>>
>>>>>>
>>>>>> Not using -Scc.   Why would you use that and expect it not to delete
>>>>>> packages?
>>>>>>
>>>>>> A
>>>>>>
>>>>>
>>>>> Because I want everything deleted in the main /var/cache/pacman/pkg dir.
>>>>>
>>>>
>>>> Pacman asks what to do for each cache directory and you could say yes to
>>>> removing files from /var/cache/pacman/pkg/ and no for other cache
>>>> directories.   So that already achieves what you are doing without
>>>> adding a special case to the codebase.
>>>>
>>>> Pacman's job is not to be a specialised cache cleaning utility.  Hence
>>>> why the suggestion of adding the ability to select how many versions of
>>>> each package is kept was implemented in paccache.
>>>>
>>>> Allan
>>>>
>>>
>>> Yes, that does work but then you have to be careful about what to wipe
>>> and can't automate it. I would agree if it wasn't for the case
>>> accidentally deleting that dir loses you your repo.
>>>
>>> I believe as a workaround aurutils bind mounts the repo into cache as
>>> readonly.
>>>
>>> Would you be more accepting of it straight up just skipping any
>>> cachedirs that happen to be a local repo and not inspect it at all?
>>
>> -1.  -Sc/-Scc are destructive operations.  There are a variety of
>> weird cache setups where they could be more destructive than intended.
>> People with weird cache setups really probably just shouldn't use
>> them.
>>
> 
> Do you have any alternate solution in mind?
>

There are a range of possibilities. e.g. a script containing:

pacman --cachedir=/var/cache/pacman/pkg/ -Scc