Unify var tracking between webkit and the proxy.

ppapi/proxy/plugin_var_serialization_rules.cc

 // Copyright (c) 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "ppapi/proxy/plugin_var_serialization_rules.h"
 
 #include "base/logging.h"
 #include "ppapi/proxy/plugin_dispatcher.h"
+#include "ppapi/proxy/plugin_resource_tracker.h"
 #include "ppapi/proxy/plugin_var_tracker.h"
+#include "ppapi/shared_impl/var.h"
+
+using ppapi::StringVar;
 
 namespace pp {
 namespace proxy {
 
 PluginVarSerializationRules::PluginVarSerializationRules()
-    : var_tracker_(PluginVarTracker::GetInstance()) {
+    : var_tracker_(&PluginResourceTracker::GetInstance()->var_tracker()) {
 }
 
 PluginVarSerializationRules::~PluginVarSerializationRules() {
 }
 
 PP_Var PluginVarSerializationRules::SendCallerOwned(const PP_Var& var,
                                                     std::string* str_val) {
   // Objects need special translations to get the IDs valid in the host.
   if (var.type == PP_VARTYPE_OBJECT)
     return var_tracker_->GetHostObject(var);
 
   // Retrieve the string to use for IPC.
   if (var.type == PP_VARTYPE_STRING) {
-    const std::string* var_string = var_tracker_->GetExistingString(var);
-    if (var_string)
-      *str_val = *var_string;
+    scoped_refptr<StringVar> string_var(StringVar::FromPPVar(var));
+    if (string_var.get())
+      *str_val = string_var->value();
     else
       NOTREACHED() << "Trying to send unknown string over IPC.";
   }
   return var;
 }
 
 PP_Var PluginVarSerializationRules::BeginReceiveCallerOwned(
     const PP_Var& var,
     const std::string* str_val,
     Dispatcher* dispatcher) {
-  if (var.type == PP_VARTYPE_STRING) {
-    // Convert the string to the context of the current process.
-    PP_Var ret;
-    ret.type = PP_VARTYPE_STRING;
-    ret.value.as_id = var_tracker_->MakeString(*str_val);
-    return ret;
-  }
+  if (var.type == PP_VARTYPE_STRING)
+    return StringVar::StringToPPVar(0, *str_val);

[dmichael (off chromium), 2011/08/08 22:13:59]

The 0 for module is just because Module is irrelevant on the plugin side, since
there's 1 per process? Could you add a comment or a separate function to make it
clearer?

[brettw, 2011/08/09 17:08:09]

Correct, I've been wanting to force people do to the right thing, so I filed a
bug (we should have some global ID we use for cases like this).

 
   if (var.type == PP_VARTYPE_OBJECT) {
     DCHECK(dispatcher->IsPlugin());
     return var_tracker_->TrackObjectWithNoReference(
         var, static_cast<PluginDispatcher*>(dispatcher));
   }
 
   return var;
 }
 
 void PluginVarSerializationRules::EndReceiveCallerOwned(const PP_Var& var) {
   if (var.type == PP_VARTYPE_STRING) {
     // Destroy the string BeginReceiveCallerOwned created above.
-    var_tracker_->Release(var);
+    var_tracker_->ReleaseVar(var);
   } else if (var.type == PP_VARTYPE_OBJECT) {
     var_tracker_->StopTrackingObjectWithNoReference(var);
   }
 }
 
 PP_Var PluginVarSerializationRules::ReceivePassRef(const PP_Var& var,
                                                    const std::string& str_val,
                                                    Dispatcher* dispatcher) {
-  if (var.type == PP_VARTYPE_STRING) {
-    // Convert the string to the context of the current process.
-    PP_Var ret;
-    ret.type = PP_VARTYPE_STRING;
-    ret.value.as_id = var_tracker_->MakeString(str_val);
-    return ret;
-  }
+  if (var.type == PP_VARTYPE_STRING)
+    return StringVar::StringToPPVar(0, str_val);
 
   // Overview of sending an object with "pass ref" from the browser to the
   // plugin:
   //                                  Example 1             Example 2
   //                               Plugin   Browser      Plugin   Browser
   // Before send                      3        2            0        1
   // Browser calls BeginSendPassRef   3        2            0        1
   // Plugin calls ReceivePassRef      4        1            1        1
   // Browser calls EndSendPassRef     4        1            1        1
   //
@@ skipping 29 matching lines @@
   // entire ref count in the plugin. When the plugin refcount goes to 0, it
   // will call the browser to deref the object. This is why in example 2
   // transferring the object ref to the browser involves no net change in the
   // browser's refcount.
 
   // Objects need special translations to get the IDs valid in the host.
   if (var.type == PP_VARTYPE_OBJECT)
     return var_tracker_->GetHostObject(var);
 
   if (var.type == PP_VARTYPE_STRING) {
-    const std::string* var_string = var_tracker_->GetExistingString(var);
-    if (var_string)
-      *str_val = *var_string;
+    scoped_refptr<StringVar> string_var(StringVar::FromPPVar(var));
+    if (string_var.get())
+      *str_val = string_var->value();
     else
       NOTREACHED() << "Trying to send unknown string over IPC.";
   }
   return var;
 }
 
 void PluginVarSerializationRules::EndSendPassRef(const PP_Var& var,
                                                  Dispatcher* dispatcher) {
   // See BeginSendPassRef for an example of why we release our ref here.
   // The var we have in our inner class has been converted to a host object
   // by BeginSendPassRef. This means it's not a normal var valid in the plugin,
   // so we need to use the special ReleaseHostObject.
   if (var.type == PP_VARTYPE_OBJECT) {
     var_tracker_->ReleaseHostObject(
         static_cast<PluginDispatcher*>(dispatcher), var);
   }
 }
 
 void PluginVarSerializationRules::ReleaseObjectRef(const PP_Var& var) {
-  var_tracker_->Release(var);
+  var_tracker_->ReleaseVar(var);
 }
 
 }  // namespace proxy
 }  // namespace pp