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 136022)
+++ chrome/renderer/pepper/ppb_nacl_private_impl.cc	(working copy)
@@ -9,26 +9,47 @@
 #include "base/command_line.h"
 #include "base/lazy_instance.h"
 #include "base/logging.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/renderer/render_thread.h"
+#include "content/public/renderer/render_view.h"
 #include "ipc/ipc_sync_message_filter.h"
-#include "native_client/src/shared/imc/nacl_imc.h"
 #include "ppapi/c/private/ppb_nacl_private.h"
 #include "ppapi/native_client/src/trusted/plugin/nacl_entry_points.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/ppapi_plugin_instance.h"
 
 #if defined(OS_WIN)
 #include "content/public/common/sandbox_init.h"
 #endif
 
+using content::RenderThread;
+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;
 
+IPC::ChannelHandle g_plugin_ppapi_channel;

[dmichael (off chromium), 2012/05/10 19:38:58]

I think this one will have to be a LazyInstance if it stays global. The next two
are probably okay as-is.

+base::ProcessHandle g_plugin_process_handle;
+base::ProcessId g_plugin_process_id;

[dmichael (off chromium), 2012/05/10 19:38:58]

Suppose one page has >1 NaCl module embedded on it...  won't we need 1 of each
of these per instance? Maybe they should be out-params of LaunchSelLdr, like
imc_handles is?

[bbudge, 2012/05/11 01:21:16]

This is just for the sake of getting something working. It will probably need to
be a map. That's why I added the PP_Instance param to LaunchSelLdr, so we can
match things up.

+
 // Launch NaCl's sel_ldr process.
-bool LaunchSelLdr(const char* alleged_url, int socket_count,
+bool LaunchSelLdr(PP_Instance instance,
+                  const char* alleged_url, int socket_count,
                   void* imc_handles) {
   std::vector<nacl::FileDescriptor> sockets;
   IPC::Message::Sender* sender = content::RenderThread::Get();
@@ -36,7 +57,10 @@
     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_plugin_ppapi_channel,
+          &g_plugin_process_handle,
+          &g_plugin_process_id)))
     return false;
 
   CHECK(static_cast<int>(sockets.size()) == socket_count);
@@ -44,9 +68,37 @@
     static_cast<nacl::Handle*>(imc_handles)[i] =
         nacl::ToNativeHandle(sockets[i]);
   }
+
   return true;
 }
 
+bool StartPpapiProxy(PP_Instance instance) {
+  // Using the RenderView, establish the HostDispatcher for the PPAPI proxy.

[dmichael (off chromium), 2012/05/10 19:38:58]

I think this comment might be better right before you do it, instead of right
before the sanity checks.

[bbudge, 2012/05/11 01:21:16]

Done.

+  webkit::ppapi::PluginInstance* plugin_instance =
+      content::GetHostGlobals()->GetInstance(instance);
+  if (!plugin_instance)
+    return false;
+  FilePath plugin_path;
+  if (!PathService::Get(chrome::FILE_NACL_PLUGIN, &plugin_path))
+    return false;
+  if (g_plugin_ppapi_channel.name.empty())
+    return false;
+
+  if (CommandLine::ForCurrentProcess()->HasSwitch(
+          switches::kEnableNaClIPCProxy)) {

[dmichael (off chromium), 2012/05/10 19:38:58]

Maybe you should check for that switch at the beginning, and bail? I know that
the first half of the function doesn't do anything interesting, but putting the
switch check early will make sure we don't accidentally add some interesting
behavior outside of the switch check.

[bbudge, 2012/05/11 01:21:16]

Yes indeed.

+    WebView* view =
+        plugin_instance->container()->element().document().frame()->view();
+    content::RenderView* render_view = content::RenderView::FromWebView(view);
+    render_view->CreatePepperHostDispatcher(plugin_path,
+                                            g_plugin_process_id,
+                                            g_plugin_process_handle,
+                                            g_plugin_ppapi_channel);
+    return true;
+  }
+
+  return false;
+}
+
 int UrandomFD(void) {
 #if defined(OS_POSIX)
   return GetUrandomFD();
@@ -80,6 +132,7 @@
 
 const PPB_NaCl_Private nacl_interface = {
   &LaunchSelLdr,
+  &StartPpapiProxy,
   &UrandomFD,
   &Are3DInterfacesDisabled,
   &EnableBackgroundSelLdrLaunch,