DaddyFrosty/yoga
1
0
Fork 0
Code Issues 96 Pull Requests 31 Actions Packages Projects Releases 33 Wiki Activity

Workaround for P/Invoke AccessViolationException

Browse Source 
Summary:
The issue is on ARM builds for Windows UWP. For the C# P/Invoke API wrapper, any native method that returns the YogaValue struct throws the AccessViolationException. The issue is not with structs in general, as returning the YogaSize / YGSize struct works fine. The issue seems to be limited to structs that have an enum member.

I tried a number of things to resolve the issue without changing the underlying native API for Windows. I read the ARM documentation and saw reference to variable enum sizes based on the number of enum members, so I tried to use a number of different UnmanagedType values in a [MarsalAs()] attribute on the enum member of the C# struct declaration.

What ultimately worked was to return a pointer to the location of the struct, and use the System.Runtime.InteropServices.PtrToStructure API to read the struct data from that pointer. I added a few new macros that will return the struct address on Windows only, other builds are not affected.

Note, I have not tested the impact of this ch
Closes https://github.com/facebook/yoga/pull/459

Reviewed By: emilsjolander

Differential Revision: D4652278

Pulled By: splhack

fbshipit-source-id: bf7ada4da1781e3f813b3ba331974b7bded476d9
This commit is contained in:
Eric Rozell
2017-03-06 11:29:52 -08:00
committed by Facebook Github Bot
parent 62f47190fb
commit 5bc0197c78
9 changed files with 102 additions and 78 deletions
Download Patch File Download Diff File Expand all files Collapse all files

4
csharp/Yoga/Yoga.Universal.vcxproj
View File

@@ -159,7 +159,7 @@
</PrecompiledHeader>
<WarningLevel>Level3</WarningLevel>
<Optimization>Disabled</Optimization>
<PreprocessorDefinitions>WIN32;_DEBUG;_WINDOWS;_USRDLL;YOGA_EXPORTS;FB_ASSERTIONS_ENABLED=0;%(PreprocessorDefinitions)</PreprocessorDefinitions>
<PreprocessorDefinitions>WINARMDLL;WIN32;_DEBUG;_WINDOWS;_USRDLL;YOGA_EXPORTS;FB_ASSERTIONS_ENABLED=0;%(PreprocessorDefinitions)</PreprocessorDefinitions>
<SDLCheck>true</SDLCheck>
<AdditionalIncludeDirectories>$(ProjectDir)..\..\;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
<CompileAsWinRT>false</CompileAsWinRT>
@@ -210,7 +210,7 @@
<Optimization>MaxSpeed</Optimization>
<FunctionLevelLinking>true</FunctionLevelLinking>
<IntrinsicFunctions>true</IntrinsicFunctions>
<PreprocessorDefinitions>WIN32;NDEBUG;_WINDOWS;_USRDLL;YOGA_EXPORTS;FB_ASSERTIONS_ENABLED=0;%(PreprocessorDefinitions)</PreprocessorDefinitions>
<PreprocessorDefinitions>WINARMDLL;WIN32;NDEBUG;_WINDOWS;_USRDLL;YOGA_EXPORTS;FB_ASSERTIONS_ENABLED=0;%(PreprocessorDefinitions)</PreprocessorDefinitions>
<SDLCheck>true</SDLCheck>
<AdditionalIncludeDirectories>$(ProjectDir)..\..\;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
<CompileAsWinRT>false</CompileAsWinRT>