Improved function entry hook coverage

src/api.cc

Index: src/api.cc
diff --git a/src/api.cc b/src/api.cc
old mode 100644
new mode 100755
index a06e0dbbbc640d07aabdd3938a9410741f2a2f74..b2d24d3ffa6b1f2744293a96b3bb58e6ae02432f
--- a/src/api.cc
+++ b/src/api.cc
@@ -5148,7 +5148,15 @@ void v8::V8::SetReturnAddressLocationResolver(
 
 
 bool v8::V8::SetFunctionEntryHook(FunctionEntryHook entry_hook) {

[danno, 2013/06/13 15:33:44]

API calls should take an Isolate parameter if you need it. To deprecate the
other API, you might need to have both the Isolate and non-isolate version for a
while, the non-isolate version calling the isolate version with
"i::Isolate::Current();"

[Sigurður Ásgeirsson, 2013/06/19 20:51:51]

Done.

-  return i::ProfileEntryHookStub::SetFunctionEntryHook(entry_hook);
+  i::Isolate* isolate = i::Isolate::Current();
+
+  // We don't allow switching from one hook to another, as hooks don't stack.
+  // This way a second user can at least detect that there's a problem.
+  if (entry_hook != NULL && isolate->HasFunctionEntryHook())

[danno, 2013/06/13 15:33:44]

Seems like this should be a ASSERT(entry_hook != NULL); and a if
(isolate->HasFunctionEntryHook()) {

[Sigurður Ásgeirsson, 2013/06/19 20:51:51]

Done.

+    return false;
+
+  isolate->SetFunctionEntryHook(entry_hook);

[danno, 2013/06/13 15:33:44]

It would be great to introduce some checks to make sure that this routine is
called at a time that is acceptable. It must be invoked on an Isolate before the
first code object is generated, otherwise you will get strange effects. Is there
any way to police that? Or perhaps introduce a new isolate constructor that
takes the hook to make sure that it's always set from the very beginning?
Something like that might make this functionality harder to abuse.

[Sigurður Ásgeirsson, 2013/06/19 20:51:51]

Done.

+  return true;
 }