Merge pull request #855 from bugsnag/PLAT-13024-native-stack-trace

[PLAT-13024] Send native mapped information in stack traces from system exceptions

Bugsnag/Assets/Bugsnag/Runtime/INativeClient.cs

@@ -103,13 +103,7 @@ interface INativeClient : IFeatureFlagStore
 
         IDictionary<string, object> GetNativeMetadata();
 
-        /// <summary>
-        /// Find the native loaded image that corresponds to a native instruction address
-        /// supplied by il2cpp_native_stack_trace().
-        /// </summary>
-        /// <param name="address">The address to find the corresponding image of</param>
-        /// <returns>The corresponding image, or null</returns>
-        LoadedImage FindImageAtAddress(UInt64 address);
+        StackTraceLine[] ToStackFrames(System.Exception exception);
 
         bool ShouldAttemptDelivery();
 

Bugsnag/Assets/Bugsnag/Runtime/LoadedImage.cs

@@ -4,17 +4,19 @@ namespace BugsnagUnity
 {
     class LoadedImage
     {
-        public LoadedImage(UInt64 loadAddress, UInt64 size, string fileName, string uuid)
+        public LoadedImage(UInt64 loadAddress, UInt64 size, string fileName, string uuid, bool isMainImage)
         {
             LoadAddress = loadAddress;
             Size = size;
             FileName = fileName;
             Uuid = uuid;
+            IsMainImage = isMainImage;
         }
 
         public readonly UInt64 LoadAddress;
         public readonly UInt64 Size;
         public readonly string FileName;
         public readonly string Uuid;
+        public readonly bool IsMainImage;
     }
 }

Bugsnag/Assets/Bugsnag/Runtime/Native/Android/NativeClient.cs

@@ -164,9 +164,9 @@ public void RegisterForOnSessionCallbacks()
             NativeInterface.RegisterForOnSessionCallbacks();
         }
 
-        public LoadedImage FindImageAtAddress(UInt64 address)
+        public StackTraceLine[] ToStackFrames(System.Exception exception)
         {
-            return null;
+            return new StackTraceLine[0];
         }
     }
 

Bugsnag/Assets/Bugsnag/Runtime/Native/Cocoa/LoadedImages.cs

@@ -5,40 +5,77 @@
 
 namespace BugsnagUnity
 {
+    /// <summary>
+    /// Caches the list of loaded images as reported by the native runtime, and provides searching by address.
+    /// </summary>
     class LoadedImages
     {
         /// <summary>
         /// Refresh the list of loaded images to match what the native side currently says.
         /// </summary>
+        /// <param name="mainImageFileName">The file name of the main image file</param>
         /// <remarks>
-        /// Note: You MUST call this at least once before using an instance of this class!
+        /// Note: If anything goes wrong during the refresh, the currently cached state won't change.
         /// </remarks>
-        public void Refresh()
+        #nullable enable
+        public void Refresh(String? mainImageFileName)
         {
             UInt64 loadedNativeImagesAt = NativeCode.bugsnag_lastChangedLoadedImages();
-            if (loadedNativeImagesAt == lastLoadedNativeImagesAt)
+            if (loadedNativeImagesAt == LastLoadedNativeImagesAt)
+            {
+                // Only refresh if something changed.
+                return;
+            }
+
+            var imageCount = NativeCode.bugsnag_getLoadedImageCount();
+            if (imageCount == 0)
             {
                 return;
             }
-            lastLoadedNativeImagesAt = loadedNativeImagesAt;
 
             // Ask for the current count * 2 in case new images get added between calls
-            var nativeImages = new NativeLoadedImage[NativeCode.bugsnag_getLoadedImageCount() * 2];
+            var nativeImages = new NativeLoadedImage[imageCount * 2];
             var count = NativeCode.bugsnag_getLoadedImages(nativeImages, (UInt64)nativeImages.LongLength);
-            var images = new LoadedImage[count];
-            for (UInt64 i = 0; i < count; i++)
+            try
+            {
+                if (count == 0)
+                {
+                    return;
+                }
+
+                UInt64 mainLoadAddress = 0;
+                var images = new LoadedImage[count];
+                for (UInt64 i = 0; i < count; i++)
+                {
+                    var nativeImage = nativeImages[i];
+                    var uuid = new byte[16];
+                    Marshal.Copy(nativeImage.UuidBytes, uuid, 0, 16);
+                    var fileName = Marshal.PtrToStringAnsi(nativeImage.FileName);
+                    var isMainImage = fileName == mainImageFileName;
+
+                    var image = new LoadedImage(nativeImage.LoadAddress,
+                                                nativeImage.Size,
+                                                fileName,
+                                                new Guid(uuid).ToString(),
+                                                isMainImage);
+                    if (isMainImage)
+                    {
+                        mainLoadAddress = image.LoadAddress;
+                    }
+                    images[i] = image;
+                }
+
+                // Update cache
+                Images = images;
+                MainImageLoadAddress = mainLoadAddress;
+                LowestImageLoadAddress = images[0].LoadAddress;
+                LastLoadedNativeImagesAt = loadedNativeImagesAt;
+            }
+            finally
             {
-                var nativeImage = nativeImages[i];
-                var uuid = new byte[16];
-                Marshal.Copy(nativeImage.UuidBytes, uuid, 0, 16);
-                images[i] = new LoadedImage(nativeImage.LoadAddress,
-                                            nativeImage.Size,
-                                            Marshal.PtrToStringAnsi(nativeImage.FileName),
-                                            new Guid(uuid).ToString());
+                // bugsnag_getLoadedImages() locks a mutex, so we must call bugsnag_unlockLoadedImages()
+                NativeCode.bugsnag_unlockLoadedImages();
             }
-            Images = images;
-            // bugsnag_getLoadedImages() locks a mutex, so we must call bugsnag_unlockLoadedImages()
-            NativeCode.bugsnag_unlockLoadedImages();
         }
 
         /// <summary>
@@ -47,8 +84,14 @@ public void Refresh()
         /// </summary>
         /// <param name="address">The address to find the corresponding image of</param>
         /// <returns>The corresponding image, or null</returns>
-        public LoadedImage FindImageAtAddress(UInt64 address)
+        #nullable enable
+        public LoadedImage? FindImageAtAddress(UInt64 address)
         {
+            if (address < LowestImageLoadAddress)
+            {
+                address += MainImageLoadAddress;
+            }
+
             int idx = Array.BinarySearch(Images, address, new AddressToImageComparator());
             if (idx < 0)
             {
@@ -57,11 +100,10 @@ public LoadedImage FindImageAtAddress(UInt64 address)
             return Images[idx];
         }
 
-        /// <summary>
-        /// The currently loaded images, as of the last call to Refresh().
-        /// </summary>
-        public LoadedImage[] Images;
-        private UInt64 lastLoadedNativeImagesAt = 0;
+        private LoadedImage[] Images = new LoadedImage[0];
+        private UInt64 MainImageLoadAddress = 0;
+        private UInt64 LowestImageLoadAddress = 0;
+        private UInt64 LastLoadedNativeImagesAt = 0;
 
         private class AddressToImageComparator : IComparer
         {

Bugsnag/Assets/Bugsnag/Runtime/Native/Cocoa/NativeClient.cs

@@ -3,6 +3,7 @@
 using System;
 using System.Collections;
 using System.Collections.Generic;
+using System.Diagnostics;
 using System.IO;
 using System.Runtime.InteropServices;
 using System.Text;
@@ -20,7 +21,7 @@ class NativeClient : INativeClient
         private static NativeClient _instance;
         private bool _registeredForSessionCallbacks;
 
-        private LoadedImages loadedImages;
+        private LoadedImages loadedImages = new LoadedImages();
 
         public NativeClient(Configuration configuration)
         {
@@ -488,12 +489,121 @@ public void RegisterForOnSessionCallbacks()
             NativeCode.bugsnag_registerForSessionCallbacksAfterStart(HandleSessionCallbacks);
         }
 
-        public LoadedImage FindImageAtAddress(UInt64 address)
+        #nullable enable
+        private static string? ExtractString(IntPtr pString)
         {
-            loadedImages.Refresh();
-            return loadedImages.FindImageAtAddress(address);
+            return (pString == IntPtr.Zero) ? null : Marshal.PtrToStringAnsi(pString);
         }
 
+        private StackTraceLine[] ToStackFrames(System.Exception exception, IntPtr[] nativeAddresses)
+        {
+            var unityTrace = new PayloadStackTrace(exception.StackTrace).StackTraceLines;
+            var length = nativeAddresses.Length < unityTrace.Length ? nativeAddresses.Length : unityTrace.Length;
+            var stackFrames = new StackTraceLine[length];
+            for (int i = 0; i < length; i++)
+            {
+                var method = unityTrace[i].Method;
+                var address = (UInt64)nativeAddresses[i].ToInt64();
+                var image = loadedImages.FindImageAtAddress(address);
+
+                var trace = new StackTraceLine();
+                trace.FrameAddress = address.ToString();
+                trace.Method = method.ToString();
+                if (image != null)
+                {
+                    if (address < image.LoadAddress)
+                    {
+                        // It's a relative address
+                        trace.FrameAddress = (address + image.LoadAddress).ToString();
+                    }
+                    trace.MachoFile = image.FileName;
+                    trace.MachoLoadAddress = image.LoadAddress.ToString();
+                    trace.MachoUuid = image.Uuid;
+                    trace.InProject = image.IsMainImage;
+                }
+                stackFrames[i] = trace;
+            }
+            return stackFrames;
+        }
+
+#if ENABLE_IL2CPP && UNITY_2021_3_OR_NEWER
+        [DllImport("__Internal")]
+        private static extern IntPtr il2cpp_gchandle_get_target(int gchandle);
+
+        [DllImport("__Internal")]
+        private static extern void il2cpp_free(IntPtr ptr);
+
+        [DllImport("__Internal")]
+        private static extern void il2cpp_native_stack_trace(IntPtr exc, out IntPtr addresses, out int numFrames, out IntPtr imageUUID, out IntPtr imageName);
+#endif
+
+        public StackTraceLine[] ToStackFrames(System.Exception exception)
+        {
+            var notFound = new StackTraceLine[0];
+
+            if (exception == null)
+            {
+                return notFound;
+            }
+
+#if ENABLE_IL2CPP && UNITY_2021_3_OR_NEWER
+            var hException = GCHandle.Alloc(exception);
+            var pNativeAddresses = IntPtr.Zero;
+            var pImageUuid = IntPtr.Zero;
+            var pImageName = IntPtr.Zero;
+            try
+            {
+                if (hException == null)
+                {
+                    return notFound;
+                }
+
+                var pException = il2cpp_gchandle_get_target(GCHandle.ToIntPtr(hException).ToInt32());
+                if (pException == IntPtr.Zero)
+                {
+                    return notFound;
+                }
+
+                var frameCount = 0;
+                string? mainImageFileName = null;
+
+                il2cpp_native_stack_trace(pException, out pNativeAddresses, out frameCount, out pImageUuid, out pImageName);
+                if (pNativeAddresses == IntPtr.Zero)
+                {
+                    return notFound;
+                }
+
+                mainImageFileName = ExtractString(pImageName);
+                var nativeAddresses = new IntPtr[frameCount];
+                Marshal.Copy(pNativeAddresses, nativeAddresses, 0, frameCount);
+
+                loadedImages.Refresh(mainImageFileName);
+                return ToStackFrames(exception, nativeAddresses);
+            }
+            finally
+            {
+                if (pImageUuid != IntPtr.Zero)
+                {
+                    il2cpp_free(pImageUuid);
+                }
+                if (pImageName != IntPtr.Zero)
+                {
+                    il2cpp_free(pImageName);
+                }
+                if (pNativeAddresses != IntPtr.Zero)
+                {
+                    il2cpp_free(pNativeAddresses);
+                }
+                if (hException != null)
+                {
+                    hException.Free();
+                }
+            }
+#else
+            return notFound;
+#endif
+        }
     }
 }
+
 #endif

Bugsnag/Assets/Bugsnag/Runtime/Native/Fallback/NativeClient.cs

@@ -171,9 +171,9 @@ public void RegisterForOnSessionCallbacks()
             // Not Used on this platform
         }
 
-        public LoadedImage FindImageAtAddress(UInt64 address)
+        public StackTraceLine[] ToStackFrames(System.Exception exception)
         {
-            return null;
+            return new StackTraceLine[0];
         }
     }
 }

Bugsnag/Assets/Bugsnag/Runtime/Native/Windows/NativeClient.cs

@@ -218,9 +218,9 @@ public void RegisterForOnSessionCallbacks()
             // Not Used on this platform
         }
 
-        public LoadedImage FindImageAtAddress(UInt64 address)
+        public StackTraceLine[] ToStackFrames(System.Exception exception)
         {
-            return null;
+            return new StackTraceLine[0];
         }
     }
 }

Bugsnag/Assets/Bugsnag/Runtime/Payload/ErrorBuilder.cs

@@ -93,13 +93,19 @@ internal Error FromSystemException(System.Exception exception, string stackTrace
             return new Error(errorClass, exception.Message, lines);
         }
 
+
         internal Error FromSystemException(System.Exception exception, System.Diagnostics.StackFrame[] alternativeStackTrace)
         {
+            var frames = NativeClient.ToStackFrames(exception);
             var errorClass = exception.GetType().Name;
 
-            // JVM exceptions in the main thread are handled by unity and require extra formatting
-            if (errorClass == ANDROID_JAVA_EXCEPTION_CLASS)
+            if (frames.Length > 0)
+            {
+                return new Error(errorClass, exception.Message, frames);
+            }
+            else if (errorClass == ANDROID_JAVA_EXCEPTION_CLASS)
             {
+                // JVM exceptions in the main thread are handled by unity and require extra formatting
                 var androidErrorData = ProcessAndroidError(exception.Message);
                 var androidErrorClass = androidErrorData[0];
                 var androidErrorMessage = androidErrorData[1];