Fix sporadic 'A callback was made on a garbage collected delegate' bug

Update NuGet package details
rndusr0 · Feb 7, 2019 · a2f8e8e · a2f8e8e
1 parent 627bf27
commit a2f8e8e
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Showing 3 changed files with 26 additions and 13 deletions.
diff --git a/src/DinkToPdf/BasicConverter.cs b/src/DinkToPdf/BasicConverter.cs
@@ -58,6 +58,7 @@ public virtual byte[] Convert(IDocument document)
             }
 
             Tools.DestroyConverter(converter);
+            ProcessingDocument = null;
 
             return result;
         }

diff --git a/src/DinkToPdf/DinkToPdf.csproj b/src/DinkToPdf/DinkToPdf.csproj
@@ -2,7 +2,7 @@
 
   <PropertyGroup>
     <VersionPrefix>1.0.9</VersionPrefix>
-    <VersionSuffix>netcore2.1-wkhtmltopdf-v0.12.5</VersionSuffix>
+    <VersionSuffix>20190207.1+netstandard-2.0-netcore-2.1-wkhtmltopdf-0.12.5</VersionSuffix>
     <TargetFramework>netstandard2.0</TargetFramework>
     <NoWarn>$(NoWarn);1591</NoWarn>
     <AllowUnsafeBlocks>true</AllowUnsafeBlocks>
@@ -15,18 +15,21 @@
 
   <!--NuGet -->
   <PropertyGroup>
-    <PackageId>DinkToPdf_netstandard20</PackageId>
+    <PackageId>RndUsr0.DinkToPdf</PackageId>
     <Description>
       .NET Core P/Invoke wrapper for wkhtmltopdf library that uses Webkit engine to convert HTML pages to PDF. 
-      Upgraded to .NET Standard 2.0, .NET Core 2.1, Windows wkhtmltopdf v0.12.5
+        - Upgraded to .NET Standard 2.0, .NET Core 2.1, wkhtmltopdf v0.12.5
+        - Fix sporadic 'A callback was made on a garbage collected delegate' bug
     </Description>
     <Copyright>Copyright 2017</Copyright>
-    <Authors>Rok Dvojmoč, upgraded by Chris Bryden</Authors>
+    <License>MIT</License>
+    <Authors>Rok Dvojmoč, Chris Bryden</Authors>
     <PackageProjectUrl>https://github.com/rdvojmoc/DinkToPdf</PackageProjectUrl>
+    <PackageLicenseUrl>https://github.com/rdvojmoc/DinkToPdf/blob/master/LICENSE</PackageLicenseUrl>    
     <RepositoryUrl>https://github.com/rndusr0/DinkToPdf</RepositoryUrl>
     <IncludeBuildOutput>true</IncludeBuildOutput>
     <IncludeSymbols>true</IncludeSymbols>
-    <PackageTags>wkhtmltopdf;netstandard;html;pdf;wrapper</PackageTags>
+    <PackageTags>wkhtmltopdf;netstandard;netcore;html;pdf;wrapper</PackageTags>
     <GeneratePackageOnBuild>true</GeneratePackageOnBuild>
   </PropertyGroup>
 
@@ -40,19 +43,19 @@
       <PackagePath>runtimes\win-x64\native</PackagePath>
       <CopyToOutputDirectory>Always</CopyToOutputDirectory>
     </Content>
-    <Content Include="..\..\v0.12.4\32 bit\libwkhtmltox.dylib">
+    <Content Include="..\..\v0.12.5\32 bit\libwkhtmltox.dylib">
       <Pack>true</Pack>
       <PackagePath>runtimes\osx-x86\native</PackagePath>
     </Content>
-    <Content Include="..\..\v0.12.4\32 bit\libwkhtmltox.so">
+    <Content Include="..\..\v0.12.5\32 bit\libwkhtmltox.so">
       <Pack>true</Pack>
       <PackagePath>runtimes\linux-x86\native</PackagePath>
     </Content>
-    <Content Include="..\..\v0.12.4\64 bit\libwkhtmltox.dylib">
+    <Content Include="..\..\v0.12.5\64 bit\libwkhtmltox.dylib">
       <Pack>true</Pack>
       <PackagePath>runtimes\osx-x64\native</PackagePath>
     </Content>
-    <Content Include="..\..\v0.12.4\64 bit\libwkhtmltox.so">
+    <Content Include="..\..\v0.12.5\64 bit\libwkhtmltox.so">
       <Pack>true</Pack>
       <PackagePath>runtimes\linux-x64\native</PackagePath>
     </Content>

diff --git a/src/DinkToPdf/PdfTools.cs b/src/DinkToPdf/PdfTools.cs
@@ -12,12 +12,16 @@ public sealed class PdfTools : ITools
     {
         public bool IsLoaded { get; private set; }
 
+        //used to maintain a reference to delegates to prevent them being garbage collected...
+        private List<object> _Delegates = new List<object>();
+
         public PdfTools()
         {
             IsLoaded = false;
         }
-
-        public void Load() {
+
+        public void Load()
+        {
 
             if (IsLoaded)
             {
@@ -55,7 +59,7 @@ public unsafe string GetGlobalSetting(IntPtr settings, string name)
             //default const char * size is 2048 bytes 
             byte[] buffer = new byte[2048];
 
-            fixed (byte* tempBuffer = buffer  )
+            fixed (byte* tempBuffer = buffer)
             {
                 WkHtmlToXBindings.wkhtmltopdf_get_global_setting(settings, name, tempBuffer, buffer.Length);
             }
@@ -118,7 +122,7 @@ public bool DoConversion(IntPtr converter)
 
         public void DestroyConverter(IntPtr converter)
         {
-             WkHtmlToXBindings.wkhtmltopdf_destroy_converter(converter);
+            WkHtmlToXBindings.wkhtmltopdf_destroy_converter(converter);
         }
 
         public byte[] GetConversionResult(IntPtr converter)
@@ -134,26 +138,31 @@ public byte[] GetConversionResult(IntPtr converter)
 
         public int SetPhaseChangedCallback(IntPtr converter, VoidCallback callback)
         {
+            _Delegates.Add(callback);
             return WkHtmlToXBindings.wkhtmltopdf_set_phase_changed_callback(converter, callback);
         }
 
         public int SetProgressChangedCallback(IntPtr converter, VoidCallback callback)
         {
+            _Delegates.Add(callback);
             return WkHtmlToXBindings.wkhtmltopdf_set_progress_changed_callback(converter, callback);
         }
 
         public int SetFinishedCallback(IntPtr converter, IntCallback callback)
         {
+            _Delegates.Add(callback);
             return WkHtmlToXBindings.wkhtmltopdf_set_finished_callback(converter, callback);
         }
 
         public int SetWarningCallback(IntPtr converter, StringCallback callback)
         {
+            _Delegates.Add(callback);
             return WkHtmlToXBindings.wkhtmltopdf_set_warning_callback(converter, callback);
         }
 
         public int SetErrorCallback(IntPtr converter, StringCallback callback)
         {
+            _Delegates.Add(callback);
             return WkHtmlToXBindings.wkhtmltopdf_set_error_callback(converter, callback);
         }