1. Add flag --trace-api to trace API function invocation

runtime/lib/stacktrace.cc

 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/bootstrap_natives.h"
 #include "vm/exceptions.h"
 #include "vm/object_store.h"
 #include "vm/runtime_entry.h"
 #include "vm/stack_frame.h"
 
@@ skipping 12 matching lines @@
 // Get a concise and pertinent stack trace.
 // Arg0: stack trace object.
 // Return value: String that represents the concise and pertinent stack trace.
 DEFINE_NATIVE_ENTRY(Stacktrace_getStacktrace, 1) {
   const Stacktrace& trace =
       Stacktrace::CheckedHandle(arguments->NativeArgAt(0));
   return String::New(trace.ToCStringInternal(0));
 }
 
 
-// Setup a full stack trace.
-// Arg0: stack trace object.
-// Return value: None.
-DEFINE_NATIVE_ENTRY(Stacktrace_setupFullStacktrace, 1) {
-  const Stacktrace& trace =
-      Stacktrace::CheckedHandle(arguments->NativeArgAt(0));
-  const GrowableObjectArray& func_list =
-      GrowableObjectArray::Handle(GrowableObjectArray::New());
-  const GrowableObjectArray& code_list =
-      GrowableObjectArray::Handle(GrowableObjectArray::New());
-  const GrowableObjectArray& pc_offset_list =
-      GrowableObjectArray::Handle(GrowableObjectArray::New());
+static void iterateFrames(const GrowableObjectArray& func_list,
+                          const GrowableObjectArray& code_list,
+                          const GrowableObjectArray& pc_offset_list) {
   StackFrameIterator frames(StackFrameIterator::kDontValidateFrames);
   StackFrame* frame = frames.NextFrame();
   ASSERT(frame != NULL);  // We expect to find a dart invocation frame.
   Function& func = Function::Handle();
   Code& code = Code::Handle();
   Smi& offset = Smi::Handle();
   bool catch_frame_skipped = false;  // Tracks if catch frame has been skipped.
   while (frame != NULL) {
     if (frame->IsDartFrame()) {
       code = frame->LookupDartCode();
@@ skipping 27 matching lines @@
           } else {
             func_list.Add(func);
             code_list.Add(code);
             pc_offset_list.Add(offset);
           }
         }
       }
     }
     frame = frames.NextFrame();
   }
+}
+
+
+// Setup a full stack trace.
+// Arg0: stack trace object.
+// Return value: None.
+DEFINE_NATIVE_ENTRY(Stacktrace_setupFullStacktrace, 1) {
+  const Stacktrace& trace =
+      Stacktrace::CheckedHandle(arguments->NativeArgAt(0));
+  const GrowableObjectArray& func_list =
+      GrowableObjectArray::Handle(GrowableObjectArray::New());
+  const GrowableObjectArray& code_list =
+      GrowableObjectArray::Handle(GrowableObjectArray::New());
+  const GrowableObjectArray& pc_offset_list =
+      GrowableObjectArray::Handle(GrowableObjectArray::New());
+  iterateFrames(func_list, code_list, pc_offset_list);
   const Array& func_array = Array::Handle(Array::MakeArray(func_list));
   const Array& code_array = Array::Handle(Array::MakeArray(code_list));
   const Array& pc_offset_array =
       Array::Handle(Array::MakeArray(pc_offset_list));
   trace.SetCatchStacktrace(func_array, code_array, pc_offset_array);
   return Object::null();
 }
 
+
+// An utility method for convenient printing of dart stack traces when
+// inside 'gdb'. Note: This function will only work when there is a
+// valid exit frame information. It will not work when a breakpoint is
+// set in dart code and control is got inside 'gdb' without going through
+// the runtime or native transition stub.
+void _printCurrentStacktrace() {
+  const GrowableObjectArray& func_list =
+      GrowableObjectArray::Handle(GrowableObjectArray::New());
+  const GrowableObjectArray& code_list =
+      GrowableObjectArray::Handle(GrowableObjectArray::New());
+  const GrowableObjectArray& pc_offset_list =
+      GrowableObjectArray::Handle(GrowableObjectArray::New());
+  iterateFrames(func_list, code_list, pc_offset_list);
+  const Array& func_array = Array::Handle(Array::MakeArray(func_list));
+  const Array& code_array = Array::Handle(Array::MakeArray(code_list));
+  const Array& pc_offset_array =
+      Array::Handle(Array::MakeArray(pc_offset_list));
+  const Stacktrace& stacktrace = Stacktrace::Handle(
+      Stacktrace::New(func_array, code_array, pc_offset_array));
+  OS::Print("%s\n", stacktrace.ToCString());
+}
+
 }  // namespace dart