Add SetAbortOnUncaughtExceptionCallback API

include/v8.h

Index: include/v8.h
diff --git a/include/v8.h b/include/v8.h
index 395354341120de691db72afbd7b69f433b5e8f63..64b85ce8229ad3b58b26695640a7b89f0ded5616 100644
--- a/include/v8.h
+++ b/include/v8.h
@@ -5378,6 +5378,18 @@ class V8_EXPORT Isolate {
   static Isolate* GetCurrent();
 
   /**
+   * Custom callback used by embedders to help V8 determine if it should abort
+   * when it throws and no internal handler can catch the exception.
+   * If FLAG_abort_on_uncaught_exception is true, then V8 will abort if either:

[Michael Starzinger, 2015/10/01 16:34:38]

nit: The "FLAG_abort_on_uncaught_exception" is an internal variable, in the
public API I would rather reference the "--abort-on-uncaught-exception" command
line flag, as that is something that the embedder can actually control.

Also I would rephrase the wording slightly to say "no internal handler is
predicted to catch the exception", because whether a finally-handler will
re-throw an exception or not is essentially an undecidable problem and hence
cannot be predicted at throw time. We essentially "predict" every
finally-handler will re-throw, which is just an assumption/guess on V8's part.

Also it might make sense to mentioned explicitly that if
"--abort-on-uncaught-exception" is not set, then the callback will never fire.

[Michael Starzinger, 2015/10/01 16:36:30]

Actually, I just realized: We conservatively assume any finally clause will
behave as if the exception were consumed. But that doesn't change the above
argument.

[julien.gilli, 2015/10/01 19:18:11]

Acknowledged.

[julien.gilli, 2015/10/01 19:18:11]

Acknowledged.

[julien.gilli, 2015/10/05 17:24:24]

Done.

[julien.gilli, 2015/10/05 17:24:24]

Done.

+   * - no custom callback is set.
+   * - the custom callback set returns true.
+   * Otherwise it won't abort.
+   */
+  typedef bool (*AbortOnUncaughtExceptionCallback)(Isolate*);
+  void SetAbortOnUncaughtExceptionCallback(
+      AbortOnUncaughtExceptionCallback callback);
+
+  /**
    * Methods below this point require holding a lock (using Locker) in
    * a multi-threaded environment.
    */