Add a print function in the global JS scope for debugging.

experimental/SkV8Example/SkV8Example.cpp

 /*
  * Copyright 2013 Google Inc.
  *
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  *
  */
 #include <v8.h>
 
@@ skipping 274 matching lines @@
 void SkV8ExampleWindow::onHandleInval(const SkIRect& rect) {
     RECT winRect;
     winRect.top = rect.top();
     winRect.bottom = rect.bottom();
     winRect.right = rect.right();
     winRect.left = rect.left();
     InvalidateRect((HWND)this->getHWND(), &winRect, false);
 }
 #endif
 
+
+// The callback that is invoked by v8 whenever the JavaScript 'print'
+// function is called.  Prints its arguments on stdout separated by
+// spaces and ending with a newline.
+void Print(const v8::FunctionCallbackInfo<v8::Value>& args) {
+    bool first = true;
+    HandleScope handle_scope(args.GetIsolate());
+    for (int i = 0; i < args.Length(); i++) {
+        if (first) {
+            first = false;
+        } else {
+            printf(" ");
+        }
+        v8::String::Utf8Value str(args[i]);
+        printf("%s", ToCString(str));
+    }
+    printf("\n");
+    fflush(stdout);
+}
+
+
 // Creates a new execution environment containing the built-in
 // function draw().
 Handle<Context> createRootContext(Isolate* isolate) {
   // Create a template for the global object.
   Handle<ObjectTemplate> global = ObjectTemplate::New();
 
   // This is where we would inject any globals into the root Context
   // using global->Set(...)
 
+  global->Set(v8::String::NewFromUtf8(isolate, "print"),
+              v8::FunctionTemplate::New(Print));
+
   return Context::New(isolate, NULL, global);
 }
 
 
 // Parse and run script. Then fetch out the onDraw function from the global
 // object.
 bool JsCanvas::initialize(const char script[]) {
 
     // Create a stack-allocated handle scope.
     HandleScope handleScope(fIsolate);
@@ skipping 87 matching lines @@
     if (NULL == script) {
         printf("Could not load file: %s.\n", FLAGS_infile[0]);
         exit(1);
     }
     if (!jsCanvas->initialize(script)) {
         printf("Failed to initialize.\n");
         exit(1);
     }
     return new SkV8ExampleWindow(hwnd, jsCanvas);
 }