Add an IPC channel between the NaCl loader process and the renderer.

chrome/renderer/pepper/ppb_nacl_private_impl.cc

Index: chrome/renderer/pepper/ppb_nacl_private_impl.cc
===================================================================
--- chrome/renderer/pepper/ppb_nacl_private_impl.cc	(revision 137272)
+++ chrome/renderer/pepper/ppb_nacl_private_impl.cc	(working copy)
@@ -7,25 +7,50 @@
 #ifndef DISABLE_NACL
 
 #include "base/command_line.h"
+#include "base/compiler_specific.h"
 #include "base/lazy_instance.h"
 #include "base/logging.h"
+#include "base/message_loop.h"
+#include "base/path_service.h"
 #include "base/rand_util_c.h"
+#include "chrome/common/chrome_paths.h"
+#include "chrome/common/chrome_switches.h"
 #include "chrome/common/render_messages.h"
+#include "content/public/common/content_client.h"
 #include "content/public/common/content_switches.h"
+#include "content/public/common/sandbox_init.h"
 #include "content/public/renderer/render_thread.h"
+#include "content/public/renderer/render_view.h"
 #include "ipc/ipc_sync_message_filter.h"
 #include "ppapi/c/private/ppb_nacl_private.h"
 #include "ppapi/native_client/src/trusted/plugin/nacl_entry_points.h"
+#include "ppapi/proxy/host_dispatcher.h"
+#include "ppapi/proxy/proxy_channel.h"
+#include "ppapi/shared_impl/ppapi_preferences.h"
+#include "third_party/WebKit/Source/WebKit/chromium/public/WebDocument.h"
+#include "third_party/WebKit/Source/WebKit/chromium/public/WebElement.h"
+#include "third_party/WebKit/Source/WebKit/chromium/public/WebFrame.h"
+#include "third_party/WebKit/Source/WebKit/chromium/public/WebPluginContainer.h"
+#include "third_party/WebKit/Source/WebKit/chromium/public/WebView.h"
+#include "webkit/plugins/ppapi/host_globals.h"
+#include "webkit/plugins/ppapi/plugin_module.h"
+#include "webkit/plugins/ppapi/ppapi_plugin_instance.h"
 
-#if defined(OS_WIN)
-#include "content/public/common/sandbox_init.h"
-#endif
+using content::RenderThread;
+using content::RenderView;
+using webkit::ppapi::HostGlobals;
+using webkit::ppapi::PluginInstance;
+using WebKit::WebView;
 
 namespace {
 
 base::LazyInstance<scoped_refptr<IPC::SyncMessageFilter> >
     g_background_thread_sender = LAZY_INSTANCE_INITIALIZER;
 
+base::LazyInstance<IPC::ChannelHandle> g_ipc_channel_handle =
+    LAZY_INSTANCE_INITIALIZER;
+base::ProcessId g_plugin_process_id;
+
 // Launch NaCl's sel_ldr process.
 PP_Bool LaunchSelLdr(PP_Instance instance,
                      const char* alleged_url, int socket_count,
@@ -36,7 +61,9 @@
     sender = g_background_thread_sender.Pointer()->get();
 
   if (!sender->Send(new ChromeViewHostMsg_LaunchNaCl(
-          GURL(alleged_url), socket_count, &sockets)))
+          GURL(alleged_url), socket_count, &sockets,
+          g_ipc_channel_handle.Pointer(),
+          &g_plugin_process_id)))
     return PP_FALSE;
 
   CHECK(static_cast<int>(sockets.size()) == socket_count);
@@ -48,7 +75,141 @@
   return PP_TRUE;
 }
 
+class ProxyChannelDelegate
+    : public ppapi::proxy::ProxyChannel::Delegate {
+ public:
+  ProxyChannelDelegate();
+  virtual ~ProxyChannelDelegate();
+
+  // ProxyChannel::Delegate implementation.
+  virtual base::MessageLoopProxy* GetIPCMessageLoop() OVERRIDE;
+  virtual base::WaitableEvent* GetShutdownEvent() OVERRIDE;
+  virtual IPC::PlatformFileForTransit ShareHandleWithRemote(
+      base::PlatformFile handle,
+      const IPC::SyncChannel& channel,
+      bool should_close_source) OVERRIDE;
+ private:
+  base::WaitableEvent shutdown_event_;
+};
+
+ProxyChannelDelegate::ProxyChannelDelegate()
+    : shutdown_event_(true, false) {}
+
+ProxyChannelDelegate::~ProxyChannelDelegate() {
+}
+
+base::MessageLoopProxy* ProxyChannelDelegate::GetIPCMessageLoop() {
+  return RenderThread::Get()->GetIOMessageLoopProxy().get();
+}
+
+base::WaitableEvent* ProxyChannelDelegate::GetShutdownEvent() {
+  return &shutdown_event_;
+}
+
+IPC::PlatformFileForTransit ProxyChannelDelegate::ShareHandleWithRemote(
+    base::PlatformFile handle,
+    const IPC::SyncChannel& channel,
+    bool should_close_source) {
+  return content::BrokerGetFileHandleForProcess(handle, channel.peer_pid(),
+                                                should_close_source);
+}
+
+// Stubbed out SyncMessageStatusReceiver, required by HostDispatcher.
+class SyncMessageStatusReceiver
+    : public ppapi::proxy::HostDispatcher::SyncMessageStatusReceiver {
+ public:
+  SyncMessageStatusReceiver() {}
+  virtual ~SyncMessageStatusReceiver() {}
+
+  // SyncMessageStatusReceiver implementation.
+  virtual void BeginBlockOnSyncMessage() {}
+  virtual void EndBlockOnSyncMessage() {}
+};
+
+class OutOfProcessProxy
+    : public webkit::ppapi::PluginDelegate::OutOfProcessProxy {
+ public:
+  OutOfProcessProxy() {}
+  virtual ~OutOfProcessProxy() {}
+
+  bool Init(const IPC::ChannelHandle& channel_handle,
+            PP_Module pp_module,
+            PP_GetInterface_Func local_get_interface,
+            const ppapi::Preferences& preferences,
+            SyncMessageStatusReceiver* status_receiver) {
+    if (channel_handle.name.empty())
+      return false;
+
+#if defined(OS_POSIX)
+    DCHECK_NE(-1, channel_handle.socket.fd);
+    if (channel_handle.socket.fd == -1)
+      return false;
+#endif
+
+    dispatcher_delegate_.reset(new ProxyChannelDelegate);
+    dispatcher_.reset(new ppapi::proxy::HostDispatcher(
+        pp_module, local_get_interface, status_receiver));
+
+    if (!dispatcher_->InitHostWithChannel(dispatcher_delegate_.get(),
+                                          channel_handle,
+                                          true,  // Client.
+                                          preferences)) {
+      dispatcher_.reset();
+      dispatcher_delegate_.reset();
+      return false;
+    }
+
+    return true;
+  }
+
+  // OutOfProcessProxy implementation.
+  virtual const void* GetProxiedInterface(const char* name) {

[dmichael (off chromium), 2012/05/23 00:41:04]

OVERRIDE for these?

[bbudge, 2012/05/23 21:42:20]

Done.

+    return dispatcher_->GetProxiedInterface(name);
+  }
+  virtual void AddInstance(PP_Instance instance) {
+    ppapi::proxy::HostDispatcher::SetForInstance(instance, dispatcher_.get());
+  }
+  virtual void RemoveInstance(PP_Instance instance) {
+    ppapi::proxy::HostDispatcher::RemoveForInstance(instance);
+  }
+
+ private:
+  scoped_ptr<ppapi::proxy::HostDispatcher> dispatcher_;
+  scoped_ptr<ppapi::proxy::ProxyChannel::Delegate> dispatcher_delegate_;
+};
+
 PP_Bool StartPpapiProxy(PP_Instance instance) {
+  if (CommandLine::ForCurrentProcess()->HasSwitch(
+          switches::kEnableNaClIPCProxy)) {
+    IPC::ChannelHandle& channel_handle = g_ipc_channel_handle.Get();
+    if (channel_handle.name.empty())
+      return PP_FALSE;
+
+    webkit::ppapi::PluginInstance* plugin_instance =
+        content::GetHostGlobals()->GetInstance(instance);
+    if (!plugin_instance)
+      return PP_FALSE;
+
+    WebView* web_view =
+        plugin_instance->container()->element().document().frame()->view();
+    RenderView* render_view = content::RenderView::FromWebView(web_view);
+
+    webkit::ppapi::PluginModule* plugin_module = plugin_instance->module();
+
+    scoped_refptr<SyncMessageStatusReceiver>
+        status_receiver(new SyncMessageStatusReceiver());
+    scoped_ptr<OutOfProcessProxy> out_of_process_proxy(new OutOfProcessProxy);
+    if (out_of_process_proxy->Init(
+            channel_handle,
+            plugin_module->pp_module(),
+            webkit::ppapi::PluginModule::GetLocalGetInterfaceFunc(),
+            ppapi::Preferences(render_view->GetWebkitPreferences()),
+            status_receiver.get())) {
+      plugin_module->InitAsProxied(out_of_process_proxy.release());

[dmichael (off chromium), 2012/05/23 00:41:04]

I think this might cause trouble...  this module has already been initialized.

One possible problem with this... If you look at "GetPluginInterface" in
webkit/plugins/ppapi/plugin_module.cc. Before this point, it will return
interface pointers for the NaCl plugin's PPP interfaces. After this point, it
will return pointers to the IPC proxy's host-side PPP interfaces. So... 
anything cached before this (like ppapi_plugin_instance.cc does in its
Load*Interface() functions) will never get sent to the IPC proxy. We'll have to
figure some strategy for this.

+      return PP_TRUE;
+    }
+  }
+
   return PP_FALSE;
 }