[arch-dev-public] install scripts in core

[Allan McRae]

Allan McRae wrote:
> Xavier wrote:
>> On Mon, Feb 2, 2009 at 6:24 PM, Aaron Griffin 
>> <aaronmgriffin at gmail.com> wrote:
>>  
>>> The way pacman calls the scriptlets, it actually uses the shell from
>>> the _parent_ system. I know this for a fact, because Dan and I
>>> investigated, added checks for bash in the chroot, then realized it
>>> didn't matter and reverted it.
>>>
>>> Are you _sure_ it's bash failing like you suspect? What happens if you
>>> just install vi and library deps in a chroot and try to run things
>>> manually?
>>>
>>>     
>>
>> I am not sure why we are talking about bash here, the shell used is
>> /bin/sh which can be any shells, right?
>> Are you sure the shell from the parent system is used? I could not
>> find this documented anywhere.
>> How do you explain that installing bash or adding a sh->dash symlink
>> inside the chroot helps then?
>>
>> To Allan : did you find any scriptlets which actually worked without
>> bash installed? Even the most basic scriptlet not doing anything does
>> not work here.
>>   
>
> In short, No.  But why am I getting no install scriptlet errors when I 
> install all of base you might ask...  Well, that was doing my head in 
> and here is the answer. 
> Doing a "pamcan -r somedir -S base" installs the following programs 
> who have install scriptlet (according to ABS) before bash:
>    glibc,readline, db, pam, shadow
>
> glibc, db and shadow do not use post_install so they do not test the 
> need for bash.   However, both readline and pam do use post_install so 
> it appears they are running. Why is that?  Because the package do not 
> actually include the install script due to lack of install line in 
> their PKGBUILD.
> All my tests with dummy packages with post_install scripts doing 
> simple things like "return 0" or even nothing do not work unless bash 
> is installed.  So it looks like we are really using the bash on the 
> _child_ system, not the parent.  Which would make sense (how do you 
> chroot to the child system and still access the parents bash?).
>

And here is my plan to fix this. 
- Remove the post_install script from readline - it is installed before 
tex-info anyway due to readline -> bash -> gzip -> tex-info.  I'd give 
texinfo a dep on 'sh' in case the bash->gzip link ever breaks.
- All packages (at least in core) with an install script must depend on 
'sh' and programs needed to run their install script functions (see 
start of thread).

We run into a problem if any dep of bash needs a pre/post_install.  
These packages currently are kernel-headers, tzdata, glibc, ncurses, and 
readline.  Now wait for Dan to point out that dash has no deps so could 
be our default sh...  which is why I suggest depending on 'sh' rather 
than bash.

Allan