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
Depends on:
Reported: 2012-01-19 19:15 UTC by Fabien GIGANTE
Modified: 2016-08-25 11:54 UTC (History)
2 users (show)

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

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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();
      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 :