3 files changed, 44 insertions, 0 deletions
diff --git a/ppapi/cpp/instance.cc b/ppapi/cpp/instance.cc
index 72676d1..025741f 100644
--- a/ppapi/cpp/instance.cc
+++ b/ppapi/cpp/instance.cc
@@ -4,6 +4,7 @@
 
 #include "ppapi/cpp/instance.h"
 
+#include "ppapi/c/dev/ppb_messaging_dev.h"
 #include "ppapi/c/dev/ppp_printing_dev.h"
 #include "ppapi/c/ppb_instance.h"
 #include "ppapi/cpp/common.h"
@@ -25,6 +26,10 @@ template <> const char* interface_name<PPB_Instance>() {
   return PPB_INSTANCE_INTERFACE;
 }
 
+template <> const char* interface_name<PPB_Messaging_Dev>() {
+  return PPB_MESSAGING_DEV_INTERFACE;
+}
+
 }  // namespace
 
 Instance::Instance(PP_Instance instance) : pp_instance_(instance) {
@@ -61,6 +66,10 @@ bool Instance::HandleInputEvent(const PP_InputEvent& /*event*/) {
   return false;
 }
 
+void Instance::HandleMessage(const Var& /*message_data*/) {
+  return;
+}
+
 Var Instance::GetInstanceObject() {
   return Var();
 }
@@ -115,6 +124,13 @@ Var Instance::ExecuteScript(const Var& script, Var* exception) {
                  Var::OutException(exception).get()));
 }
 
+void Instance::PostMessage(const Var& message) {
+  if (!has_interface<PPB_Messaging_Dev>())
+    return;
+  get_interface<PPB_Messaging_Dev>()->PostMessage(pp_instance(),
+                                                  message.pp_var());
+}
+
 void Instance::AddPerInstanceObject(const std::string& interface_name,
                                     void* object) {
   // Ensure we're not trying to register more than one object per interface
diff --git a/ppapi/cpp/instance.h b/ppapi/cpp/instance.h
index 497189f..69de79f 100644
--- a/ppapi/cpp/instance.h
+++ b/ppapi/cpp/instance.h
@@ -96,6 +96,16 @@ class Instance {
 
   /** See PPB_Instance.ExecuteScript. */
   Var ExecuteScript(const Var& script, Var* exception = NULL);
+
+  // These functions use the PPP_Messaging and PPB_Messaging interfaces, so that
+  // messaging can be done conveniently for a pp::Instance without using a
+  // separate C++ class.
+
+  /** See PPP_Messaging.HandleMessage. */
+  virtual void HandleMessage(const Var& message_data);
+  /** See PPB_Messaging.PostMessage. */
+  void PostMessage(const Var& message);
+
   // @}
 
   /**
diff --git a/ppapi/cpp/module.cc b/ppapi/cpp/module.cc
index 220609d..f64041d 100644
--- a/ppapi/cpp/module.cc
+++ b/ppapi/cpp/module.cc
@@ -25,6 +25,7 @@
 
 #include <string.h>
 
+#include "ppapi/c/dev/ppp_messaging_dev.h"
 #include "ppapi/c/pp_instance.h"
 #include "ppapi/c/pp_var.h"
 #include "ppapi/c/ppp_instance.h"
@@ -134,6 +135,20 @@ static PPP_Instance instance_interface = {
   &Instance_GetInstanceObject
 };
 
+void Messaging_HandleMessage(PP_Instance pp_instance, PP_Var var) {
+  Module* module_singleton = Module::Get();
+  if (!module_singleton)
+    return;
+  Instance* instance = module_singleton->InstanceForPPInstance(pp_instance);
+  if (!instance)
+    return;
+  instance->HandleMessage(Var(Var::PassRef(), var));
+}
+
+static PPP_Messaging_Dev instance_messaging_interface = {
+  &Messaging_HandleMessage
+};
+
 // Module ----------------------------------------------------------------------
 
 Module::Module() : pp_module_(0), get_browser_interface_(NULL), core_(NULL) {
@@ -152,6 +167,9 @@ const void* Module::GetPluginInterface(const char* interface_name) {
   if (strcmp(interface_name, PPP_INSTANCE_INTERFACE) == 0)
     return &instance_interface;
 
+  if (strcmp(interface_name, PPP_MESSAGING_DEV_INTERFACE) == 0)
+    return &instance_messaging_interface;
+
   // Now see if anything was dynamically registered.
   InterfaceMap::const_iterator found = additional_interfaces_.find(
       std::string(interface_name));