[Vm-dev] [Pharo-dev] Better management of encoding of environment variables

[Eliot Miranda]

Hi Sven,

On Wed, Jan 16, 2019 at 2:37 AM Sven Van Caekenberghe <sven at stfx.eu> wrote:

> Still, one of the conclusions of previous discussions about the encoding
> of environment variables was/is that there is no single correct solution.
> OS's are not consistent in how the encoding is done in all (historical)
> contexts (like sometimes, 1 env var defines the encoding to use for others,
> different applications do different things, and other such nice stuff), and
> certainly not across platforms.
>
> So this is really complex.
>
> Do we want to hide this in some obscure VM C code that very few people can
> see, read, let alone help with ?
>
> The image side is perfectly capable of dealing with platform differences
> in a clean/clear way, and at least we can then use the full power of our
> language and our tools.
>

Agreed.  At the same time I think it is very important that we don't reply
on the FFI for environment variable access.  This is a basic cross-platform
facility.  So I would like to see the environment accessed through
primitives, but have the image place interpretation on the result of the
primitive(s), and have the primitive(s) answer a raw result, just a
sequence of uninterpreted bytes.

VisualWorks takes this approach and provides a class UninterpretedBytes
that the VM is aware of.  That's always seemed like an ugly name and
overkill to me.  I would just use ByteArray and provide image level
conversion from ByteArray to String, which is what I believe we have anyway.


> > On 16 Jan 2019, at 10:59, Guillermo Polito <guillermopolito at gmail.com>
> wrote:
> >
> > Hi Nicolas,
> >
> > On Wed, Jan 16, 2019 at 10:25 AM Nicolas Cellier <
> nicolas.cellier.aka.nice at gmail.com> wrote:
> > IMO, windows VM (and plugins) should do the UCS2 -> UTF8 conversion
> because the purpose of a VM is to provide an OS independant façade.
> > I made progress recently in this area, but we should finish the
> job/test/consolidate.
> >
> > I'm following your changes for windows from the shadows and I think they
> are awesome :).
> >
> > If someone bypass the VM and use direct windows API thru FFI, then he
> takes the responsibility, but uniformity doesn't hurt.
> >
> >  So far we are using FFI for this, as you say we create first
> Win32WideStrings from utf8 strings and then we use ffi calls to the *W
> functions.
> > I don't think we can make it for Pharo7.0.0. The cycle to build, do some
> acceptance tests, and then bless a new VM as stable is far too long for our
> inminent release :).
> >
> > But this could be for a 7.1.0, and if you like I can surely give a hand
> on this.
> >
> > Guille
>
>
>

-- 
_,,,^..^,,,_
best, Eliot
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.squeakfoundation.org/pipermail/vm-dev/attachments/20190116/661bee2c/attachment.html>