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

ppapi/native_client/src/trusted/plugin/plugin.cc

Index: ppapi/native_client/src/trusted/plugin/plugin.cc
===================================================================
--- ppapi/native_client/src/trusted/plugin/plugin.cc	(revision 143375)
+++ ppapi/native_client/src/trusted/plugin/plugin.cc	(working copy)
@@ -34,6 +34,7 @@
 #include "native_client/src/trusted/desc/nacl_desc_wrapper.h"
 #include "native_client/src/trusted/nonnacl_util/sel_ldr_launcher.h"
 #include "native_client/src/trusted/plugin/json_manifest.h"
+#include "native_client/src/trusted/plugin/nacl_entry_points.h"
 #include "native_client/src/trusted/plugin/nacl_subprocess.h"
 #include "native_client/src/trusted/plugin/nexe_arch.h"
 #include "native_client/src/trusted/plugin/plugin_error.h"
@@ -54,6 +55,7 @@
 #include "ppapi/c/ppp_input_event.h"
 #include "ppapi/c/ppp_instance.h"
 #include "ppapi/c/ppp_mouse_lock.h"
+#include "ppapi/c/private/ppb_nacl_private.h"
 #include "ppapi/c/private/ppb_uma_private.h"
 #include "ppapi/cpp/dev/find_dev.h"
 #include "ppapi/cpp/dev/printing_dev.h"
@@ -120,6 +122,13 @@
 const int64_t kSizeKBMax = 512*1024;     // very large .nexe
 const uint32_t kSizeKBBuckets = 100;
 
+const PPB_NaCl_Private* GetNaclInterface() {

[Mark Seaborn, 2012/06/22 01:09:17]

Nit: Should be "GetNaClInterface"

+  pp::Module *module = pp::Module::Get();

[Mark Seaborn, 2012/06/22 01:09:17]

Nit: Should be "* " here.

+  CHECK(module);
+  return static_cast<const PPB_NaCl_Private*>(
+      module->GetBrowserInterface(PPB_NACL_PRIVATE_INTERFACE));
+}
+
 const PPB_UMA_Private* GetUMAInterface() {
   pp::Module *module = pp::Module::Get();
   CHECK(module);
@@ -602,13 +611,32 @@
     return false;
   }
 
+  void* ipc_channel_handle = NULL;
   bool service_runtime_started =
-      new_service_runtime->Start(wrapper, error_info, manifest_base_url());
+      new_service_runtime->Start(wrapper,
+                                 error_info,
+                                 manifest_base_url(),
+                                 &ipc_channel_handle);
+  nacl::scoped_ptr<char> ipc_channel_handle_ptr(

[Mark Seaborn, 2012/06/22 01:09:17]

Storing a ChannelHandle as a nacl::scoped_ptr<char> seems like a bad idea. 
You'd still be leaking a handle/FD or other std::string internals on error.  It
would be better not to try to free it here, and if there's a leak, comment it
with a TODO.

+      reinterpret_cast<char*>(ipc_channel_handle));
   PLUGIN_PRINTF(("Plugin::LoadNaClModuleCommon (service_runtime_started=%d)\n",
                  service_runtime_started));
   if (!service_runtime_started) {
     return false;
   }
+
+  // Try to start the Chrome IPC-based proxy.
+  const PPB_NaCl_Private* ppb_nacl = GetNaclInterface();
+  if (ppb_nacl->StartPpapiProxy(

[Mark Seaborn, 2012/06/22 01:09:17]

Thinking about this more, if StartPpapiProxy() is called immediate after
Start(), why not fold it into the LaunchSelLdr() function?  You can make
LaunchSelLdr() return a result indicating whether we're using the new proxy.

+          pp_instance(),
+          reinterpret_cast<void*>(ipc_channel_handle_ptr.release()))) {
+    using_ipc_proxy_ = true;
+    // We need to explicitly schedule this here. It is normally called in
+    // response to starting the SRPC proxy.
+    CHECK(init_done_cb.pp_completion_callback().func != NULL);
+    PLUGIN_PRINTF(("Plugin::LoadNaClModuleCommon, started ipc proxy.\n"));
+    pp::Module::Get()->core()->CallOnMainThread(0, init_done_cb, PP_OK);
+  }
   return true;
 }
 
@@ -631,6 +659,11 @@
 }
 
 bool Plugin::LoadNaClModuleContinuationIntern(ErrorInfo* error_info) {
+  // If we are using the IPC proxy, StartSrpcServices and StartJSObjectProxy
+  // don't makes sense. Return 'true' so that the plugin continues loading.
+  if (using_ipc_proxy_)
+    return true;
+
   if (!main_subprocess_.StartSrpcServices()) {
     error_info->SetReport(ERROR_SRPC_CONNECTION_FAIL,
                           "SRPC connection failure for " +
@@ -862,7 +895,8 @@
       init_time_(0),
       ready_time_(0),
       nexe_size_(0),
-      time_of_last_progress_event_(0) {
+      time_of_last_progress_event_(0),
+      using_ipc_proxy_(false) {
   PLUGIN_PRINTF(("Plugin::Plugin (this=%p, pp_instance=%"
                  NACL_PRId32")\n", static_cast<void*>(this), pp_instance));
   callback_factory_.Initialize(this);