Add ability for embedder to provide private timeline trace data

runtime/vm/timeline.cc

 // Copyright (c) 2015, 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 <cstdlib>
 
 #include "vm/atomic.h"
 #include "vm/isolate.h"
 #include "vm/json_stream.h"
 #include "vm/lockers.h"
@@ skipping 137 matching lines @@
   ISOLATE_TIMELINE_STREAM_LIST(ISOLATE_TIMELINE_STREAM_FLAG_DEFAULT)
 #undef ISOLATE_TIMELINE_STREAM_FLAG_DEFAULT
 }
 
 
 void Timeline::SetVMStreamEnabled(bool enabled) {
   vm_stream_.set_enabled(enabled);
 }
 
 
+void Timeline::StreamStateChange(const char* stream_name,
+                                 bool prev,
+                                 bool curr) {
+  if (prev == curr) {
+    return;
+  }
+  if (strcmp(stream_name, "Embedder") == 0) {
+    if (curr && (Timeline::get_start_recording_cb() != NULL)) {
+      Timeline::get_start_recording_cb()();
+    } else if (!curr && (Timeline::get_stop_recording_cb() != NULL)) {
+      Timeline::get_stop_recording_cb()();
+    }
+  }
+}
+
+
 void Timeline::Shutdown() {
   ASSERT(recorder_ != NULL);
   if (FLAG_timeline_dir != NULL) {
     recorder_->WriteTo(FLAG_timeline_dir);
   }
   // Disable global streams.
   vm_stream_.set_enabled(false);
   vm_api_stream_.set_enabled(false);
 #define ISOLATE_TIMELINE_STREAM_DISABLE(name, not_used)                   \
   stream_##name##_enabled_ = false;
@@ skipping 98 matching lines @@
   }
   ReclaimCachedBlocksFromThreads();
   recorder->Clear();
 }
 
 
 TimelineEventRecorder* Timeline::recorder_ = NULL;
 TimelineStream Timeline::vm_stream_;
 TimelineStream Timeline::vm_api_stream_;
 MallocGrowableArray<char*>* Timeline::enabled_streams_ = NULL;
+Dart_EmbedderTimelineStartRecording Timeline::start_recording_cb_ = NULL;
+Dart_EmbedderTimelineStopRecording Timeline::stop_recording_cb_ = NULL;
+Dart_EmbedderTimelineGetTimeline Timeline::get_timeline_cb_ = NULL;
 
 #define ISOLATE_TIMELINE_STREAM_DEFINE_FLAG(name, enabled_by_default)          \
   bool Timeline::stream_##name##_enabled_ = enabled_by_default;
   ISOLATE_TIMELINE_STREAM_LIST(ISOLATE_TIMELINE_STREAM_DEFINE_FLAG)
 #undef ISOLATE_TIMELINE_STREAM_DEFINE_FLAG
 
 TimelineEvent::TimelineEvent()
     : timestamp0_(0),
       timestamp1_(0),
       arguments_(NULL),
@@ skipping 1237 matching lines @@
 TimelineEventBlock* TimelineEventBlockIterator::Next() {
   ASSERT(current_ != NULL);
   TimelineEventBlock* r = current_;
   current_ = current_->next();
   return r;
 }
 
 #endif  // !PRODUCT
 
 }  // namespace dart