[PATCH] GDI32: accept TTF-fonts without OS2 table

[Wolfgang Walter]

Signed-off-by: Wolfgang Walter 
---

fonst partially embedded in PDFs often do not contain an OS2 table.
Wine did not accept these fonts and uses another fonts as replacement
This leads often to completely unreadable documents as the glyp index does
not match the one of the choosen replacement font.

This patch accepts such fonts and inserts checks where wine assumed
that the OS2 table does exist.

Regards,

[Nikolay Sivov]

On 11/9/18 4:24 PM, Wolfgang Walter wrote:
> Signed-off-by: Wolfgang Walter
>
> fonst partially embedded in PDFs often do not contain an OS2 table.
> Wine did not accept these fonts and uses another fonts as replacement
> This leads often to completely unreadable documents as the glyp index does
> not match the one of the choosen replacement font.
>
> This patch accepts such fonts and inserts checks where wine assumed
> that the OS2 table does exist.
>
> Regards,

Hi, Wolfgang.

Thanks for the patch. Could you also open a bug report with a sample PDF 
and viewer application that you're fixing?

I'm interested in adding some tests for that case, for directwrite too.

[Wolfgang Walter]

Hello Nikolay!

On Friday, 9 November 2018 18:45:50 CET you wrote:
> On 11/9/18 4:24 PM, Wolfgang Walter wrote:
> > Signed-off-by: Wolfgang Walter
> >
> > fonst partially embedded in PDFs often do not contain an OS2 table.
> > Wine did not accept these fonts and uses another fonts as replacement
> > This leads often to completely unreadable documents as the glyp index does
> > not match the one of the choosen replacement font.
> >
> > This patch accepts such fonts and inserts checks where wine assumed
> > that the OS2 table does exist.
> >
> > Regards,
>
> Hi, Wolfgang.
>
> Thanks for the patch. Could you also open a bug report with a sample PDF
> and viewer application that you're fixing?
>
> I'm interested in adding some tests for that case, for directwrite too.

Sorry, I can't do that: the software is proprietary and I therefor cannot 
upload it. It is an ERP-software with an integrated PDF-viewer. This software 
is used by most of Germany's Studentenwerke.

I also can't provide the PDFs though I have > 100000 of them. They all contain 
personal data as they are confirmations of enrollment of the Technical 
University of Munich. I'll see if I can get one from the University generated 
from fake data but I don't know if they will do that for me.

Regards,

[Nikolay Sivov]

On 11/10/18 2:11 AM, Wolfgang Walter wrote:
> Hello Nikolay!
>
> On Friday, 9 November 2018 18:45:50 CET you wrote:
> > On 11/9/18 4:24 PM, Wolfgang Walter wrote:
> > > Signed-off-by: Wolfgang Walter
> > >
> > > fonst partially embedded in PDFs often do not contain an OS2 table.
> > > Wine did not accept these fonts and uses another fonts as replacement
> > > This leads often to completely unreadable documents as the glyp index does
> > > not match the one of the choosen replacement font.
> > >
> > > This patch accepts such fonts and inserts checks where wine assumed
> > > that the OS2 table does exist.
> > >
> > > Regards,
> >
> > Hi, Wolfgang.
> >
> > Thanks for the patch. Could you also open a bug report with a sample PDF
> > and viewer application that you're fixing?
> >
> > I'm interested in adding some tests for that case, for directwrite too.
>
> Sorry, I can't do that: the software is proprietary and I therefor cannot
> upload it. It is an ERP-software with an integrated PDF-viewer. This software
> is used by most of Germany's Studentenwerke.
>
> I also can't provide the PDFs though I have > 100000 of them. They all contain
> personal data as they are confirmations of enrollment of the Technical
> University of Munich. I'll see if I can get one from the University generated
> from fake data but I don't know if they will do that for me.

Ok, I understand. Do you know if it's using AddFontMemResourceEx()? 
(should be visible with +font log).

Regarding documents, if fonts they are using are freely to distribute, 
it would be enough if you extracted font blob from one of them.

If it's not possible, do you know which tables are still there in 
embedded font?
> Regards,

[Wolfgang Walter]

Am Samstag, 10. November 2018, 08:13:40 schrieb Nikolay Sivov:
> On 11/10/18 2:11 AM, Wolfgang Walter wrote:
> > Hello Nikolay!
> >
> > On Friday, 9 November 2018 18:45:50 CET you wrote:
> > > On 11/9/18 4:24 PM, Wolfgang Walter wrote:
> > > > Signed-off-by: Wolfgang Walter
> > > >
> > > > fonst partially embedded in PDFs often do not contain an OS2 table.
> > > > Wine did not accept these fonts and uses another fonts as replacement
> > > > This leads often to completely unreadable documents as the glyp index
> > > > does
> > > > not match the one of the choosen replacement font.
> > > >
> > > > This patch accepts such fonts and inserts checks where wine assumed
> > > > that the OS2 table does exist.
> > > >
> > > > Regards,
> > >
> > > Hi, Wolfgang.
> > >
> > > Thanks for the patch. Could you also open a bug report with a sample PDF
> > > and viewer application that you're fixing?
> > >
> > > I'm interested in adding some tests for that case, for directwrite too.
> >
> > Sorry, I can't do that: the software is proprietary and I therefor cannot
> > upload it. It is an ERP-software with an integrated PDF-viewer. This
> > software is used by most of Germany's Studentenwerke.
> >
> > I also can't provide the PDFs though I have > 100000 of them. They all
> > contain personal data as they are confirmations of enrollment of the
> > Technical University of Munich. I'll see if I can get one from the
> > University generated from fake data but I don't know if they will do that
> > for me.
>
> Ok, I understand. Do you know if it's using AddFontMemResourceEx()?
> (should be visible with +font log).

I'll look at that.
> Regarding documents, if fonts they are using are freely to distribute,
> it would be enough if you extracted font blob from one of them.

It is not a free font.

The font in the PDF contains only those characters used in the document, so I 
suppose it is created on the fly when the PDF is created.
> If it's not possible, do you know which tables are still there in
> embedded font?

As they pass (in function new_ft_face of dlls/gdi32/freetype.c) this code:

if (!pFT_Get_Sfnt_Table( ft_face, ft_sfnt_hhea ) ||
            !pFT_Get_Sfnt_Table( ft_face, ft_sfnt_head ))
        {
            TRACE("Font %s/%p lacks either an HHEA or HEAD table.\n"
                  "Skipping this font.\n", debugstr_a(file), font_data_ptr);
            goto fail;
        }

They must have

ft_sfnt_hhea
    ft_sfnt_head

Regards,

[Nikolay Sivov]

On 11/9/18 4:24 PM, Wolfgang Walter wrote:
> Signed-off-by: Wolfgang Walter
>
> fonst partially embedded in PDFs often do not contain an OS2 table.
> Wine did not accept these fonts and uses another fonts as replacement
> This leads often to completely unreadable documents as the glyp index does
> not match the one of the choosen replacement font.
>
> This patch accepts such fonts and inserts checks where wine assumed
> that the OS2 table does exist.

I tested with a randomly selected font with OS/2 table removed. Windows 
font utility installs it just fine, I sent a fix for directwrite side of 
this [1].

For gdi32 I think we'll need something similar, to fill metrics using 
available tables.
> Regards,

[Wolfgang Walter]

Am Sonntag, 11. November 2018, 21:49:33 schrieben Sie:
> On 11/9/18 4:24 PM, Wolfgang Walter wrote:
> > Signed-off-by: Wolfgang Walter
> >
> > fonst partially embedded in PDFs often do not contain an OS2 table.
> > Wine did not accept these fonts and uses another fonts as replacement
> > This leads often to completely unreadable documents as the glyp index does
> > not match the one of the choosen replacement font.
> >
> > This patch accepts such fonts and inserts checks where wine assumed
> > that the OS2 table does exist.
>
> I tested with a randomly selected font with OS/2 table removed. Windows
> font utility installs it just fine, I sent a fix for directwrite side of
> this [1].
>
> For gdi32 I think we'll need something similar, to fill metrics using
> available tables.

I'm not sure what you mean by that.

Do you think that in dlls/gdi32/freetype.c the function 
get_outline_text_metrics should handle the missing OS2 table?

I'm afraid I do not have enough knowledge of truetype fonts to change 
get_outline_text_metrics() in such a way.

With my patch get_outline_text_metrics() fails, but GetEnumStructs() could 
already handle that and seems get all needed values from somewhere else. Maybe 
the freetype library already extracts everythings it can from the other table.

All other places calling get_outline_text_metrics() also already handle that 
case.

Regards,