Add support for abortion in v8::OutputStream.

test/cctest/test-heap-profiler.cc

 // Copyright 2009 the V8 project authors. All rights reserved.
 //
 // Tests for heap profiler
 
 #ifdef ENABLE_LOGGING_AND_PROFILING
 
 #include "v8.h"
 #include "heap-profiler.h"
 #include "snapshot.h"
 #include "string-stream.h"
@@ skipping 975 matching lines @@
   CHECK_EQ(0, a_from_b->GetSelfSize());
   CHECK_EQ(0, a_from_b->GetInstancesCount());
   CHECK_EQ(0, a_from_b->GetChildrenCount());  // Retains nothing.
   CHECK(IsNodeRetainedAs(a_from_b, 1));  // B has 1 ref to A.
 }
 
 namespace {
 
 class TestJSONStream : public v8::OutputStream {
  public:
-  TestJSONStream() : eos_signaled_(0) {}
+  TestJSONStream() : eos_signaled_(0), abort_countdown_(-1) {}
+  explicit TestJSONStream(int abort_countdown)
+      : eos_signaled_(0), abort_countdown_(abort_countdown) {}
   virtual ~TestJSONStream() {}
   virtual void EndOfStream() { ++eos_signaled_; }
-  virtual void WriteAsciiChunk(char* buffer, int chars_written) {
+  virtual WriteResult WriteAsciiChunk(char* buffer, int chars_written) {
+    if (abort_countdown_ > 0) --abort_countdown_;
+    if (abort_countdown_ == 0) return kAbort;
     CHECK_GT(chars_written, 0);
     i::Vector<char> chunk = buffer_.AddBlock(chars_written, '\0');
     memcpy(chunk.start(), buffer, chars_written);
+    return kContinue;
   }
   void WriteTo(i::Vector<char> dest) { buffer_.WriteTo(dest); }
   int eos_signaled() { return eos_signaled_; }
   int size() { return buffer_.size(); }
  private:
   i::Collector<char> buffer_;
   int eos_signaled_;
+  int abort_countdown_;
 };
 
 class AsciiResource: public v8::String::ExternalAsciiStringResource {
  public:
   explicit AsciiResource(i::Vector<char> string): data_(string.start()) {
     length_ = string.length();
   }
   virtual const char* data() const { return data_; }
   virtual size_t length() const { return length_; }
  private:
@@ skipping 96 matching lines @@
   v8::Local<v8::Object> strings_array =
       parsed_snapshot->Get(v8::String::New("strings"))->ToObject();
   v8::Local<v8::String> string = strings_array->Get(string_index)->ToString();
   v8::Local<v8::String> ref_string =
       CompileRun(STRING_LITERAL_FOR_TEST)->ToString();
 #undef STRING_LITERAL_FOR_TEST
   CHECK_EQ(*v8::String::Utf8Value(ref_string),
            *v8::String::Utf8Value(string));
 }
 
+
+TEST(HeapSnapshotJSONSerializationAborting) {
+  v8::HandleScope scope;
+  LocalContext env;
+  const v8::HeapSnapshot* snapshot =
+      v8::HeapProfiler::TakeSnapshot(v8::String::New("abort"));
+  TestJSONStream stream(5);
+  snapshot->Serialize(&stream, v8::HeapSnapshot::kJSON);
+  CHECK_GT(stream.size(), 0);
+  CHECK_EQ(0, stream.eos_signaled());
+}
+
 #endif  // ENABLE_LOGGING_AND_PROFILING