Bug 2976 - accessing PrivateFontCollection.Families crashes mono
Summary: accessing PrivateFontCollection.Families crashes mono
Status: NEW
Alias: None
Product: Class Libraries
Classification: Mono
Component: System.Drawing ()
Version: 2.10.x
Hardware: PC Windows
: --- normal
Target Milestone: Untriaged
Assignee: Bugzilla
URL:
Depends on:
Blocks:
 
Reported: 2012-01-19 19:15 UTC by Fabien GIGANTE
Modified: 2016-08-25 11:54 UTC (History)
2 users (show)

Tags:
Is this bug a regression?: ---
Last known good build:

Notice (2018-05-24): bugzilla.xamarin.com is now in read-only mode.

Please join us on Visual Studio Developer Community and in the Xamarin and Mono organizations on GitHub to continue tracking issues. Bugzilla will remain available for reference in read-only mode. We will continue to work on open Bugzilla bugs, copy them to the new locations as needed for follow-up, and add the new items under Related Links.

Our sincere thanks to everyone who has contributed on this bug tracker over the years. Thanks also for your understanding as we make these adjustments and improvements for the future.


Please create a new report for Bug 2976 on GitHub or Developer Community if you have new information to add and do not yet see a matching new report.

If the latest results still closely match this report, you can use the original description:

  • Export the original title and description: GitHub Markdown or Developer Community HTML
  • Copy the title and description into the new report. Adjust them to be up-to-date if needed.
  • Add your new information.

In special cases on GitHub you might also want the comments: GitHub Markdown with public comments

Related Links:
Status:
NEW

Description Fabien GIGANTE 2012-01-19 19:15:22 UTC
Adding fonts to a PrivateFontCollection and accessing its Families member eventualy crashes mono.

It the following short code sample, the crash occurs at the program's end. In a real-life application, the crash occurs much sooner (like after one second of execution) and the application dies.

No such issue with MS.NET.

---

using System;
using System.Drawing.Text;

namespace Test
{
  static class Program
  {
    static void Main()
    {
      PrivateFontCollection collection = new PrivateFontCollection();
      collection.AddFontFile("c:\\windows\\fonts\\arial.ttf");
      int length = collection.Families.Length;
    }
  }
}
Comment 1 Fabien GIGANTE 2012-01-19 19:45:26 UTC
I think I understand where the problem is coming from.

"FontCollection.Families" is returning an array built from "new Family(IntPtr)"
But "Family.Dispose()" is calling "GDIPlus.GdipDeleteFontFamily" 

This causes the fonts of the PrivateFontCollection to be deleted much too soon...
Comment 2 Fabien GIGANTE 2012-01-19 19:58:02 UTC
Maybe calling "GdipCloneFontFamily" after "GdipGetFontCollectionFamilyList" and rturning the copies would work ?
Comment 3 Fabien GIGANTE 2016-08-25 11:54:40 UTC
I seems to be exactly whatr MS .NET does :

http://referencesource.microsoft.com/#System.Drawing/commonui/System/Drawing/Advanced/FontCollection.cs,79