From eef70d38f5a9411259efe514807631e9a282bbac Mon Sep 17 00:00:00 2001
From: Dimo <ahmed.abdelaziz@eneco.com>
Date: Thu, 8 Jan 2026 12:24:32 +0100
Subject: [PATCH] Fix recursive ExceptionObjHolderImpl crash in exception
 reporting

Add re-entrancy guards and exception handling to prevent crashes when
exceptions are thrown during exception conversion or Crashlytics reporting.

- Add atomic guard in unhandled exception hook wrapper
- Add re-entrancy protection in Crashlytics reporter
- Add try-catch fallback in exception conversion to NSException
- Prevent recursive termination handler invocation

Fixes crash: Fatal Exception: (anonymous namespace)::ExceptionObjHolderImpl
---
 .../CrashlyticsNSExceptionKtReporter.swift       | 16 ++++++++++++++++
 .../kmp/nsexceptionkt/core/NSException.kt        | 10 +++++-----
 .../nsexceptionkt/core/UnhandledExceptionHook.kt | 10 ++++++++--
 3 files changed, 29 insertions(+), 7 deletions(-)

diff --git a/NSExceptionKtCrashlytics/CrashlyticsNSExceptionKtReporter.swift b/NSExceptionKtCrashlytics/CrashlyticsNSExceptionKtReporter.swift
index 5d5a7da..6b52e0e 100644
--- a/NSExceptionKtCrashlytics/CrashlyticsNSExceptionKtReporter.swift
+++ b/NSExceptionKtCrashlytics/CrashlyticsNSExceptionKtReporter.swift
@@ -24,6 +24,8 @@ private class CrashlyticsNSExceptionKtReporter: NSExceptionKtReporter {
     
     private let crashlytics: Crashlytics
     private let causedByStrategy: CausedByStrategy
+    private static var isReporting = false
+    private static let lock = NSLock()
     
     public var requiresMergedException: Bool { causedByStrategy == .append }
     
@@ -33,6 +35,20 @@ private class CrashlyticsNSExceptionKtReporter: NSExceptionKtReporter {
     }
     
     public func reportException(_ exceptions: [NSException]) {
+        Self.lock.lock()
+        guard !Self.isReporting else {
+            Self.lock.unlock()
+            return
+        }
+        Self.isReporting = true
+        Self.lock.unlock()
+        
+        defer {
+            Self.lock.lock()
+            Self.isReporting = false
+            Self.lock.unlock()
+        }
+        
         if causedByStrategy == .logNonFatal {
             for exception in exceptions.reversed().dropLast() {
                 crashlytics.record(exceptionModel: .init(exception))
diff --git a/nsexception-kt-core/src/commonMain/kotlin/com/rickclephas/kmp/nsexceptionkt/core/NSException.kt b/nsexception-kt-core/src/commonMain/kotlin/com/rickclephas/kmp/nsexceptionkt/core/NSException.kt
index b9b8740..9e574e2 100644
--- a/nsexception-kt-core/src/commonMain/kotlin/com/rickclephas/kmp/nsexceptionkt/core/NSException.kt
+++ b/nsexception-kt-core/src/commonMain/kotlin/com/rickclephas/kmp/nsexceptionkt/core/NSException.kt
@@ -38,7 +38,7 @@ public fun addReporter(
  * of the [causes][Throwable.cause] will be appended, else causes are ignored.
  */
 @OptIn(UnsafeNumber::class, ExperimentalForeignApi::class)
-internal fun Throwable.asNSException(appendCausedBy: Boolean = false): NSException {
+internal fun Throwable.asNSException(appendCausedBy: Boolean = false): NSException = try {
     val returnAddresses = getFilteredStackTraceAddresses().let { addresses ->
         if (!appendCausedBy) return@let addresses
         addresses.toMutableList().apply {
@@ -46,10 +46,10 @@ internal fun Throwable.asNSException(appendCausedBy: Boolean = false): NSExcepti
                 addAll(cause.getFilteredStackTraceAddresses(true, addresses))
             }
         }
-    }.map {
-        NSNumber(unsignedInteger = it.convert<NSUInteger>())
-    }
-    return ThrowableNSException(name, getReason(appendCausedBy), returnAddresses)
+    }.map { NSNumber(unsignedInteger = it.convert<NSUInteger>()) }
+    ThrowableNSException(name, getReason(appendCausedBy), returnAddresses)
+} catch (e: Throwable) {
+    ThrowableNSException(name, message, emptyList())
 }
 
 /**
diff --git a/nsexception-kt-core/src/commonMain/kotlin/com/rickclephas/kmp/nsexceptionkt/core/UnhandledExceptionHook.kt b/nsexception-kt-core/src/commonMain/kotlin/com/rickclephas/kmp/nsexceptionkt/core/UnhandledExceptionHook.kt
index b44a522..0724a9b 100644
--- a/nsexception-kt-core/src/commonMain/kotlin/com/rickclephas/kmp/nsexceptionkt/core/UnhandledExceptionHook.kt
+++ b/nsexception-kt-core/src/commonMain/kotlin/com/rickclephas/kmp/nsexceptionkt/core/UnhandledExceptionHook.kt
@@ -2,6 +2,7 @@ package com.rickclephas.kmp.nsexceptionkt.core
 
 import kotlin.experimental.ExperimentalNativeApi
 import kotlin.concurrent.AtomicReference
+import kotlin.concurrent.AtomicInt
 
 /**
  * Wraps the unhandled exception hook such that the provided [hook] is invoked
@@ -13,9 +14,14 @@ import kotlin.concurrent.AtomicReference
 @OptIn(ExperimentalNativeApi::class)
 internal fun wrapUnhandledExceptionHook(hook: (Throwable) -> Unit) {
     val prevHook = AtomicReference<ReportUnhandledExceptionHook?>(null)
+    val isReporting = AtomicInt(0)
     val wrappedHook: ReportUnhandledExceptionHook = {
-        hook(it)
-        prevHook.value?.invoke(it)
+        if (isReporting.compareAndSet(0, 1)) {
+            try {
+                hook(it)
+            } catch (e: Throwable) {}
+            prevHook.value?.invoke(it)
+        }
         terminateWithUnhandledException(it)
     }
     prevHook.value = setUnhandledExceptionHook(wrappedHook)