[PATCH 2/4] qmi-codegen: add support for gdouble

[Thomas Weißschuh]

Hi,

On Fri, 2018-02-09T12:32-0600, Dan Williams wrote:
> On Fri, 2018-02-09 at 19:23 +0100, Thomas Weißschuh wrote:
> > Hi,
> > 
> > On Fri, 2018-02-09T09:48-0600, Dan Williams wrote:
> > > On Sun, 2018-01-28 at 16:50 +0100, Thomas Weißschuh wrote:
> > > > ---
> > > >  build-aux/qmi-codegen/VariableInteger.py           |  4 +++-
> > > >  build-aux/qmi-codegen/utils.py                     |  5 +---
> > > >  .../libqmi-glib/libqmi-glib-common.sections        |  1 +
> > > >  src/libqmi-glib/qmi-message.c                      | 27
> > > > ++++++++++++++++++++++
> > > >  src/libqmi-glib/qmi-message.h                      | 26
> > > > +++++++++++++++++++++
> > > >  5 files changed, 58 insertions(+), 5 deletions(-)
> > > > 
> > > > diff --git a/build-aux/qmi-codegen/VariableInteger.py b/build-
> > > > aux/qmi-codegen/VariableInteger.py
> > > > index 12d2a77..1a3001e 100644
> > > > --- a/build-aux/qmi-codegen/VariableInteger.py
> > > > +++ b/build-aux/qmi-codegen/VariableInteger.py
> > > > @@ -30,7 +30,7 @@ Variable type for signed/unsigned Integers and
> > > > floating point numbers:
> > > >   'guint32', 'gint32'
> > > >   'guint64', 'gint64'
> > > >   'guint-sized'
> > > > - 'gfloat'
> > > > + 'gfloat', 'gdouble'
> > > >  """
> > > >  class VariableInteger(Variable):
> > > >  
> > > > @@ -185,6 +185,8 @@ class VariableInteger(Variable):
> > > >              common_format = '%" G_GINT64_FORMAT "'
> > > >          elif self.private_format == 'gfloat':
> > > >              common_format = '%f'
> > > > +        elif self.private_format == 'gdouble':
> > > > +            common_format = '%f'
> > > >  
> > > >          translations = { 'lp'             : line_prefix,
> > > >                           'private_format' : self.private_format,
> > > > 
> > > 
> > > In the patches I did, there were two more spots that I changed:
> > > 
> > > emit_buffer_read() and emit_buffer_write()
> > > 
> > > not sure if those are needed but since they handled gfloat
> > > specifically, I figured they needed changing for gdouble
> > > too.  Here's
> > > the patch I used for that:
> > 
> > I am currently unsure about the endianess for gdoubles.
> > For gfloat no endianess conversion is performed although they are 4
> > bytes long.
> > So either
> > * gfloat are broken currently.
> > * gfloat are transmitted without endianess issues. This would
> > probably also
> >   apply to gdouble and we could remove the endianess logic.
> > 
> > Do you have insights into this?
> > (Probably in some documentation of the QMI protocol).
> 
> I certainly don't have access to that since you have to have an NDA to
> get it.  But I believe all the QMI messages are little-endian, so it
> may well be the case that gfloat is busted on BE arches since it's not
> swapped.
> 
> What we should really do is create some unit tests that construct the
> LE and BE final host values from byte arrays (so that we guarantee
> LE/BE byte order) and then test the swapped values against that.  But
> if gfloat is already broken, we don't need to block these patches on
> making that testcase.

Any preferences whether my patchset should drop the swapping for gdouble or
introduce it also for gfloat?
I would like to keep it consistent.

Thomas