First pass at making the proxy handle multiple renderers. This associates the

instance with resources and has most callers retrieve the dispatcher
according to the appropriate instance. This isn't hooked up to anything yet.

This changes some PPB_Flash interface methods to use PP_Bool.

The most challenging part of the change is in the plugin_var_tracker which
now needs to track which dispatcher each var object came from, and remap var
IDs since each renderer will be generating var IDs in its own space, which
will likely overlap. A similar system will need to be done for resources
which is not implemented yet.

I added some null checks in audio_impl because audio_ can be NULL in some
cases when using the trusted API. I discovered this when testing NaCl for
this patch.
Review URL: http://codereview.chromium.org/6282007

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@72053 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 200 insertions, 50 deletions

diff --git a/ppapi/proxy/plugin_var_tracker.cc b/ppapi/proxy/plugin_var_tracker.cc
index 6ad396a..42370be 100644
--- a/ppapi/proxy/plugin_var_tracker.cc
+++ b/ppapi/proxy/plugin_var_tracker.cc
@@ -1,13 +1,14 @@
-// Copyright (c) 2010 The Chromium Authors. All rights reserved.
+// 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_tracker.h"
 
 #include "base/ref_counted.h"
+#include "base/singleton.h"
 #include "ppapi/c/ppb_var.h"
-#include "ppapi/proxy/plugin_dispatcher.h"
 #include "ppapi/proxy/ppapi_messages.h"
+#include "ppapi/proxy/interface_id.h"
 
 namespace pp {
 namespace proxy {
@@ -32,28 +33,52 @@ class RefCountedString : public base::RefCounted<RefCountedString> {
 
 // When running in the plugin, this will convert the string ID to the object
 // using casting. No validity checking is done.
-RefCountedString* PluginStringFromID(int64 id) {
+RefCountedString* PluginStringFromID(PluginVarTracker::VarID id) {
   return reinterpret_cast<RefCountedString*>(static_cast<intptr_t>(id));
 }
 
 }  // namespace
 
-PluginVarTracker::PluginVarTracker(PluginDispatcher* dispatcher)
-    : dispatcher_(dispatcher) {
+PluginVarTracker::HostVar::HostVar(Sender* d, VarID i)
+    : channel(d),
+      host_object_id(i) {
 }
 
-PluginVarTracker::~PluginVarTracker() {}
+bool PluginVarTracker::HostVar::operator<(const HostVar& other) const {
+  if (channel < other.channel)
+    return true;
+  if (other.channel < channel)
+    return false;
+  return host_object_id < other.host_object_id;
+}
+
+PluginVarTracker::PluginVarInfo::PluginVarInfo(const HostVar& host_var)
+    : host_var(host_var),
+      ref_count(0),
+      track_with_no_reference_count(0) {
+}
 
-int64 PluginVarTracker::MakeString(const std::string& str) {
+PluginVarTracker::PluginVarTracker() : last_plugin_object_id_(0) {
+}
+
+PluginVarTracker::~PluginVarTracker() {
+}
+
+PluginVarTracker* PluginVarTracker::GetInstance() {
+  return Singleton<PluginVarTracker>::get();
+}
+
+PluginVarTracker::VarID PluginVarTracker::MakeString(const std::string& str) {
   RefCountedString* out = new RefCountedString(str);
   out->AddRef();
-  return static_cast<int64>(reinterpret_cast<intptr_t>(out));
+  return static_cast<VarID>(reinterpret_cast<intptr_t>(out));
 }
 
-int64 PluginVarTracker::MakeString(const char* str, uint32_t len) {
+PluginVarTracker::VarID PluginVarTracker::MakeString(const char* str,
+                                                     uint32_t len) {
   RefCountedString* out = new RefCountedString(str, len);
   out->AddRef();
-  return static_cast<int64>(reinterpret_cast<intptr_t>(out));
+  return static_cast<VarID>(reinterpret_cast<intptr_t>(out));
 }
 
 std::string PluginVarTracker::GetString(const PP_Var& var) const {
@@ -72,16 +97,20 @@ void PluginVarTracker::AddRef(const PP_Var& var) {
   if (var.type == PP_VARTYPE_STRING) {
     PluginStringFromID(var.value.as_id)->AddRef();
   } else if (var.type == PP_VARTYPE_OBJECT && var.value.as_id != 0) {
-    int& ref_count = object_ref_count_[var.value.as_id];
-    ref_count++;
-    if (ref_count == 1) {
-      // We must handle the case where we got requested to AddRef an object
-      // that we've never seen before. This should tell the browser we've
-      // taken a ref. This comes up when the browser passes an object as an
-      // input param and holds a ref for us. We may not have seen that object
-      // and the plugin handler may want to AddRef and release it internally.
-      SendAddRefObjectMsg(var.value.as_id);
+    PluginVarInfoMap::iterator found = plugin_var_info_.find(var.value.as_id);
+    if (found == plugin_var_info_.end()) {
+      NOTREACHED() << "Requesting to addref an unknown object.";
+      return;
+    }
+
+    PluginVarInfo& info = found->second;
+    if (info.ref_count == 0) {
+      // Got an AddRef for an object we have no existing reference for.
+      // We need to tell the browser we've taken a ref. This comes up when the
+      // browser passes an object as an input param and holds a ref for us.
+      SendAddRefObjectMsg(info.host_var);
     }
+    info.ref_count++;
   }
 }
 
@@ -89,47 +118,168 @@ void PluginVarTracker::Release(const PP_Var& var) {
   if (var.type == PP_VARTYPE_STRING) {
     PluginStringFromID(var.value.as_id)->Release();
   } else if (var.type == PP_VARTYPE_OBJECT) {
-    ObjectRefCount::iterator found = object_ref_count_.find(var.value.as_id);
-    if (found == object_ref_count_.end())
-      return;  // Invalid object.
-    found->second--;
-
-    if (found->second == 0) {
-      // Plugin has released all of its refs, tell the browser.
-      object_ref_count_.erase(found);
-      SendReleaseObjectMsg(var.value.as_id);
+    PluginVarInfoMap::iterator found = plugin_var_info_.find(var.value.as_id);
+    if (found == plugin_var_info_.end()) {
+      NOTREACHED() << "Requesting to release an unknown object.";
+      return;
     }
+
+    PluginVarInfo& info = found->second;
+    if (info.ref_count == 0) {
+      NOTREACHED() << "Releasing an object with zero ref.";
+      return;
+    }
+
+    info.ref_count--;
+    if (info.ref_count == 0)
+      SendReleaseObjectMsg(info.host_var);
+    DeletePluginVarInfoIfNecessary(found);
   }
 }
 
-void PluginVarTracker::ReceiveObjectPassRef(const PP_Var& var) {
-  // We're the plugin and the renderer just sent us a ref. The renderer has
-  // addrefed the var in its tracker for us since it's returning it.
-  //
-  // - If We don't have a reference to this already, then we just add it to
-  //   our tracker and use that one ref.
-  //
-  // - If we do already have a reference to it, that means the renderer now
-  //   has two references on our behalf. We want to transfer that extra
-  //   reference to our list. This means we addref in the plugin, and release
-  //   the extra one in the renderer.
-  ObjectRefCount::iterator found = object_ref_count_.find(var.value.as_id);
-  if (found == object_ref_count_.end()) {
-    object_ref_count_[var.value.as_id] = 1;
+PP_Var PluginVarTracker::ReceiveObjectPassRef(const PP_Var& var,
+                                              Sender* channel) {
+  DCHECK(var.type == PP_VARTYPE_OBJECT);
+
+  // Find the plugin info.
+  PluginVarInfoMap::iterator found =
+      FindOrMakePluginVarFromHostVar(var, channel);
+  if (found == plugin_var_info_.end()) {
+    // The above code should have always made an entry in the map.
+    NOTREACHED();
+    return PP_MakeUndefined();
+  }
+
+  // Fix up the references. The host (renderer) just sent us a ref. The
+  // renderer has addrefed the var in its tracker for us since it's returning
+  // it.
+  PluginVarInfo& info = found->second;
+  if (info.ref_count == 0) {
+    // We don't have a reference to this already, then we just add it to our
+    // tracker and use that one ref.
+    info.ref_count = 1;
   } else {
-    SendReleaseObjectMsg(var.value.as_id);
-    found->second++;
+    // We already have a reference to it, that means the renderer now has two
+    // references on our behalf. We want to transfer that extra reference to
+    // our list. This means we addref in the plugin, and release the extra one
+    // in the renderer.
+    SendReleaseObjectMsg(info.host_var);
+    info.ref_count++;
   }
+
+  PP_Var ret;
+  ret.type = PP_VARTYPE_OBJECT;
+  ret.value.as_id = found->first;
+  return ret;
 }
 
-void PluginVarTracker::SendAddRefObjectMsg(int64_t id) {
-  dispatcher_->Send(new PpapiHostMsg_PPBVar_AddRefObject(
-      INTERFACE_ID_PPB_VAR_DEPRECATED, id));
+PP_Var PluginVarTracker::TrackObjectWithNoReference(const PP_Var& host_var,
+                                                    Sender* channel) {
+  DCHECK(host_var.type == PP_VARTYPE_OBJECT);
+
+  PluginVarInfoMap::iterator found =
+      FindOrMakePluginVarFromHostVar(host_var, channel);
+  if (found == plugin_var_info_.end()) {
+    // The above code should have always made an entry in the map.
+    NOTREACHED();
+    return PP_MakeUndefined();
+  }
+
+  found->second.track_with_no_reference_count++;
+
+  PP_Var ret;
+  ret.type = PP_VARTYPE_OBJECT;
+  ret.value.as_id = found->first;
+  return ret;
 }
 
-void PluginVarTracker::SendReleaseObjectMsg(int64_t id) {
-  dispatcher_->Send(new PpapiHostMsg_PPBVar_ReleaseObject(
-      INTERFACE_ID_PPB_VAR_DEPRECATED, id));
+void PluginVarTracker::StopTrackingObjectWithNoReference(
+    const PP_Var& plugin_var) {
+  DCHECK(plugin_var.type == PP_VARTYPE_OBJECT);
+  PluginVarInfoMap::iterator found = plugin_var_info_.find(
+      plugin_var.value.as_id);
+  if (found == plugin_var_info_.end()) {
+    NOTREACHED();
+    return;
+  }
+
+  found->second.track_with_no_reference_count--;
+  DeletePluginVarInfoIfNecessary(found);
+}
+
+PP_Var PluginVarTracker::GetHostObject(const PP_Var& plugin_object) const {
+  DCHECK(plugin_object.type == PP_VARTYPE_OBJECT);
+  PluginVarInfoMap::const_iterator found = plugin_var_info_.find(
+      plugin_object.value.as_id);
+  if (found == plugin_var_info_.end()) {
+    NOTREACHED();
+    return PP_MakeUndefined();
+  }
+  PP_Var ret;
+  ret.type = PP_VARTYPE_OBJECT;
+  ret.value.as_id = found->second.host_var.host_object_id;
+  return ret;
+}
+
+int PluginVarTracker::GetRefCountForObject(const PP_Var& plugin_object) {
+  PluginVarInfoMap::iterator found = plugin_var_info_.find(
+      plugin_object.value.as_id);
+  if (found == plugin_var_info_.end())
+    return -1;
+  return found->second.ref_count;
+}
+
+int PluginVarTracker::GetTrackedWithNoReferenceCountForObject(
+    const PP_Var& plugin_object) {
+  PluginVarInfoMap::iterator found = plugin_var_info_.find(
+      plugin_object.value.as_id);
+  if (found == plugin_var_info_.end())
+    return -1;
+  return found->second.track_with_no_reference_count;
+}
+
+void PluginVarTracker::SendAddRefObjectMsg(const HostVar& host_var) {
+  host_var.channel->Send(new PpapiHostMsg_PPBVar_AddRefObject(
+      INTERFACE_ID_PPB_VAR_DEPRECATED, host_var.host_object_id));
+}
+
+void PluginVarTracker::SendReleaseObjectMsg(const HostVar& host_var) {
+  host_var.channel->Send(new PpapiHostMsg_PPBVar_ReleaseObject(
+      INTERFACE_ID_PPB_VAR_DEPRECATED, host_var.host_object_id));
+}
+
+PluginVarTracker::PluginVarInfoMap::iterator
+PluginVarTracker::FindOrMakePluginVarFromHostVar(const PP_Var& var,
+                                                 Sender* channel) {
+  DCHECK(var.type == PP_VARTYPE_OBJECT);
+  HostVar host_var(channel, var.value.as_id);
+
+  HostVarToPluginVarMap::iterator found =
+      host_var_to_plugin_var_.find(host_var);
+  if (found != host_var_to_plugin_var_.end()) {
+    PluginVarInfoMap::iterator ret = plugin_var_info_.find(found->second);
+    DCHECK(ret != plugin_var_info_.end());
+    return ret;  // Already know about this var return the ID.
+  }
+
+  // Make a new var, adding references to both maps.
+  VarID new_plugin_var_id = ++last_plugin_object_id_;
+  host_var_to_plugin_var_[host_var] = new_plugin_var_id;
+  return plugin_var_info_.insert(
+      std::make_pair(new_plugin_var_id, PluginVarInfo(host_var))).first;
+}
+
+void PluginVarTracker::DeletePluginVarInfoIfNecessary(
+    PluginVarInfoMap::iterator iter) {
+  if (iter->second.ref_count != 0 ||
+      iter->second.track_with_no_reference_count != 0)
+    return;  // Object still alive.
+
+  // Object ref counts are all zero, delete from both maps.
+  DCHECK(host_var_to_plugin_var_.find(iter->second.host_var) !=
+         host_var_to_plugin_var_.end());
+  host_var_to_plugin_var_.erase(iter->second.host_var);
+  plugin_var_info_.erase(iter);
 }
 
 }  // namesace proxy