A Dissabte 03 Maig 2008, Ross Moore va escriure: > Hi Pino, > > On 02/05/2008, at 9:27 PM, Pino Toscano wrote: > > Alle venerdì 02 maggio 2008, James Cloos ha scritto: > >> After I recompiled poppler and xpdf-on-poppler with -ggdb I no longer > >> get the SEGV from pdftoppm, only from xpdf. It looks like: > > > > ... not really useful, as all the interesting part is stripped. > > Attached you find a much better backtrace, that clearly shows the > > problem. > > > > In AnnotWidget::initialize(), in case there is a global Form object > > (that > > corresponds to the AcroForm object in the Catalog), it looks for the > > reference of the current (form widget) annotation in the fields of the > > AcroForm. But (at least in the first of the two documents) the > > Fields entry > > in AcroForm has no entries, and thus a null FormWidget* is > > returned, but it's > > dereferenced anyway, -> crash. > > When AR opens the PDF it displays a message "Fixing Form Fields", > then opens the document anyway. > Until now, I've not known the reason for this. > > This also means that every PDF document containing form fields, > that has been created using pdfTeX with the hyperref.sty macro package, > has been technically invalid by having an empty /Fields [ ] array. > > Acrobat doesn't mind, since it fixes the document upon opening. > Other browsers need not do this --- with interesting consequences, > as we have discovered.
Wait, we are not sure this is actually a real bug in the pdf, the spec seems a bit not clear in that field, do you know who wrote that piece of code? Albert > > > Fixing this properly is going to require changes to the driver file > hpdftex.def (part of the hyperref macro package) and probably > also changes within pdfTeX itself. > > > I attached a very simple patch that checks whether the FormWidget* > > is valid, > > and the faulty pages of the documents seem to load fine now. > > Iñigo, what do you think? > > Thanks very much for this observation. > It gives me a good idea of both what was wrong, and also a way > to fix it --- for my owm documents, but not in full generality. > > > -- > > Pino Toscano > > Cheers, > > Ross > > ------------------------------------------------------------------------ > Ross Moore [EMAIL PROTECTED] > Mathematics Department office: E7A-419 > Macquarie University tel: +61 (0)2 9850 8955 > Sydney, Australia 2109 fax: +61 (0)2 9850 8114 > ------------------------------------------------------------------------ > > > > _______________________________________________ > poppler mailing list > [email protected] > http://lists.freedesktop.org/mailman/listinfo/poppler _______________________________________________ poppler mailing list [email protected] http://lists.freedesktop.org/mailman/listinfo/poppler
