Re: Gnumeric 1.0.10

[Jody Goldberg <jody gnome org>]

On Tue, Oct 08, 2002 at 10:03:37PM +0100, Nick Lamb wrote:
> Is it intended that Gnumeric should not crash when handling
> invalid XL data
Yes, as we write new code more range checking is going in.  However,
I have tried to avoid going back and doing mass cleanups at this
stage.  That will be in another cycle.  My goal would be something
similar to the graph import/export code.  It is much more stringent.

Catch the obvious stuff as you go.

> My first non-OLE XLS file loaded last night.
great.  It may make it in for 1.2 then.

> 1. What's the preferred way to handle pure BIFF XLS in the boot.c
> file ?
The same way we handle 'Workbook' vs 'Book'
If zip sniffing fails try to use the raw stream.  Best to have some
sort of sniffing on it though so that we can probe accurately

> 2. Early (like 2.1) XLS is a skeleton of what we have today. So there
> is no BOF-Workbook, should I conjure a workbook into existence when I
> detect the old version tags in BOF-Worksheet, or ... ?
That sounds about right.  Pretend there is a workbook.

> 3. I gather than XFs have something to do with style. But what exactly
> is going on when I try to read a worksheet and a default XF is wanted,
> can I just conjure one up with sane values from somewhere? Excel 2.1
> wasn't big on style, and Excel 3.0 isn't much better.
I had assumed that XF stood for Extended Format and that in the past
there had been a FORMAT record of some form (probably in one of the
missing lower numbers).  We map 1 XF -> 1 MStyle.  The easiest thing
to do will be to do an mstyle_default_new which creates a style with
all the modern values filled in.  Then overwrite with whatever you
can extract from the old records.

Good Luck
    Jody