Fix bug where transient pages would miss events dispatched while it was

chrome/browser/extensions/extension_message_service.cc

 // Copyright (c) 2012 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 "chrome/browser/extensions/extension_message_service.h"
 
 #include "base/atomic_sequence_num.h"
 #include "base/bind.h"
 #include "base/callback.h"
 #include "base/json/json_writer.h"
 #include "base/stl_util.h"
 #include "base/values.h"
 #include "chrome/browser/extensions/extension_host.h"
 #include "chrome/browser/extensions/extension_process_manager.h"
 #include "chrome/browser/extensions/extension_service.h"
+#include "chrome/browser/extensions/extension_system.h"
 #include "chrome/browser/extensions/extension_tab_util.h"
 #include "chrome/browser/extensions/lazy_background_task_queue.h"
 #include "chrome/browser/extensions/process_map.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/tab_contents/tab_util.h"
 #include "chrome/browser/ui/tab_contents/tab_contents_wrapper.h"
 #include "chrome/common/chrome_notification_types.h"
 #include "chrome/common/chrome_view_type.h"
 #include "chrome/common/extensions/extension.h"
 #include "chrome/common/extensions/extension_messages.h"
@@ skipping 14 matching lines @@
 
 // Port1 is always even, port2 is always odd.
 #define IS_OPENER_PORT_ID(port_id) (((port_id) & 1) == 0)
 
 // Change even to odd and vice versa, to get the other side of a given channel.
 #define GET_OPPOSITE_PORT_ID(source_port_id) ((source_port_id) ^ 1)
 
 struct ExtensionMessageService::MessagePort {
   content::RenderProcessHost* process;
   int routing_id;
-  explicit MessagePort(content::RenderProcessHost* process = NULL,
-                       int routing_id = MSG_ROUTING_CONTROL)
-     : process(process), routing_id(routing_id) {}
+  std::string extension_id;
+  void* background_host_ptr;  // used in IncrementLazyKeepaliveCount
+
+  MessagePort()
+     : process(NULL),
+       routing_id(MSG_ROUTING_CONTROL),
+       background_host_ptr(NULL) {}
+  MessagePort(content::RenderProcessHost* process,
+              int routing_id,
+              const std::string& extension_id)
+     : process(process),
+       routing_id(routing_id),
+       extension_id(extension_id),
+       background_host_ptr(NULL) {}
 };
 
 struct ExtensionMessageService::MessageChannel {
   ExtensionMessageService::MessagePort opener;
   ExtensionMessageService::MessagePort receiver;
-  std::string source_extension_id;
-  std::string target_extension_id;
 };
 
 struct ExtensionMessageService::OpenChannelParams {
   content::RenderProcessHost* source;
   std::string tab_json;
   MessagePort receiver;
   int receiver_port_id;
   std::string source_extension_id;
   std::string target_extension_id;
   std::string channel_name;
@@ skipping 12 matching lines @@
         source_extension_id(source_extension_id),
         target_extension_id(target_extension_id),
         channel_name(channel_name) {}
 };
 
 namespace {
 
 static base::StaticAtomicSequenceNumber g_next_channel_id;
 
 static void DispatchOnConnect(const ExtensionMessageService::MessagePort& port,
-                              int dest_port_id,
-                              const std::string& channel_name,
+                              int dest_port_id, const std::string& channel_name,

[Yoyo Zhou, 2012/04/19 21:47:13]

nit: why this change?

[Matt Perry, 2012/04/19 22:21:53]

Just bringing it up to style code:
http://dev.chromium.org/developers/coding-style#TOC-Code-formatting

[Yoyo Zhou, 2012/04/19 22:32:55]

It doesn't look particularly recommended for function declarations.

[Matt Perry, 2012/04/19 22:35:00]

See bullet point that starts "For function declarations and definitions"

                               const std::string& tab_json,
                               const std::string& source_extension_id,
                               const std::string& target_extension_id) {
   port.process->Send(new ExtensionMsg_DispatchOnConnect(
       port.routing_id, dest_port_id, channel_name,
       tab_json, source_extension_id, target_extension_id));
 }
 
 static void DispatchOnDisconnect(
     const ExtensionMessageService::MessagePort& port, int source_port_id,
@@ skipping 13 matching lines @@
   SiteInstance* site_instance =
       profile->GetExtensionProcessManager()->GetSiteInstanceForURL(
           Extension::GetBaseURLFromExtensionId(extension_id));
 
   if (!site_instance->HasProcess())
     return NULL;
 
   return site_instance->GetProcess();
 }
 
-static void IncrementLazyKeepaliveCount(content::RenderProcessHost* process,
-                                        const std::string& extension_id) {
-  Profile* profile = Profile::FromBrowserContext(process->GetBrowserContext());
-  const Extension* extension = profile->GetExtensionService()->extensions()->
-      GetByID(extension_id);
-  if (extension)
-    profile->GetExtensionProcessManager()->IncrementLazyKeepaliveCount(
-        extension);
+static void IncrementLazyKeepaliveCount(
+    ExtensionMessageService::MessagePort* port) {
+  Profile* profile =
+      Profile::FromBrowserContext(port->process->GetBrowserContext());
+  ExtensionProcessManager* pm =
+      ExtensionSystem::Get(profile)->process_manager();
+  ExtensionHost* host = pm->GetBackgroundHostForExtension(port->extension_id);
+  if (host && host->extension()->has_lazy_background_page())
+    pm->IncrementLazyKeepaliveCount(host->extension());
+
+  // Keep track of the background host, so when we decrement, we only do so if
+  // the host hasn't reloaded.
+  port->background_host_ptr = host;
 }
 
-static void DecrementLazyKeepaliveCount(content::RenderProcessHost* process,
-                                        const std::string& extension_id) {
-  Profile* profile = Profile::FromBrowserContext(process->GetBrowserContext());
-  const Extension* extension = profile->GetExtensionService()->extensions()->
-      GetByID(extension_id);
-  if (extension)
-    profile->GetExtensionProcessManager()->DecrementLazyKeepaliveCount(
-        extension);
+static void DecrementLazyKeepaliveCount(
+    ExtensionMessageService::MessagePort* port) {
+  Profile* profile =
+      Profile::FromBrowserContext(port->process->GetBrowserContext());
+  ExtensionProcessManager* pm =
+      ExtensionSystem::Get(profile)->process_manager();
+  ExtensionHost* host = pm->GetBackgroundHostForExtension(port->extension_id);
+  if (host && host == port->background_host_ptr)
+    pm->DecrementLazyKeepaliveCount(host->extension());
 }
 
 }  // namespace
 
 // static
 void ExtensionMessageService::AllocatePortIdPair(int* port1, int* port2) {
   int channel_id = g_next_channel_id.GetNext();
   int port1_id = channel_id * 2;
   int port2_id = channel_id * 2 + 1;
 
@@ skipping 33 matching lines @@
       content::RenderProcessHost::FromID(source_process_id);
   if (!source)
     return;
   Profile* profile = Profile::FromBrowserContext(source->GetBrowserContext());
 
   // Note: we use the source's profile here. If the source is an incognito
   // process, we will use the incognito EPM to find the right extension process,
   // which depends on whether the extension uses spanning or split mode.
   MessagePort receiver(
       GetExtensionProcess(profile, target_extension_id),
-      MSG_ROUTING_CONTROL);
+      MSG_ROUTING_CONTROL,
+      target_extension_id);
   WebContents* source_contents = tab_util::GetWebContentsByID(
       source_process_id, source_routing_id);
 
   // Include info about the opener's tab (if it was a tab).
   std::string tab_json = "null";
   if (source_contents) {
     scoped_ptr<DictionaryValue> tab_value(
         ExtensionTabUtil::CreateTabValue(source_contents));
     base::JSONWriter::Write(tab_value.get(), &tab_json);
   }
@@ skipping 21 matching lines @@
     return;
   Profile* profile = Profile::FromBrowserContext(source->GetBrowserContext());
 
   TabContentsWrapper* contents = NULL;
   MessagePort receiver;
   if (ExtensionTabUtil::GetTabById(tab_id, profile, true,
                                    NULL, NULL, &contents, NULL)) {
     receiver.process = contents->web_contents()->GetRenderProcessHost();
     receiver.routing_id =
         contents->web_contents()->GetRenderViewHost()->GetRoutingID();
+    receiver.extension_id = extension_id;
   }
 
   if (contents && contents->web_contents()->GetController().NeedsReload()) {
     // The tab isn't loaded yet. Don't attempt to connect. Treat this as a
     // disconnect.
-    DispatchOnDisconnect(MessagePort(source, MSG_ROUTING_CONTROL),
+    DispatchOnDisconnect(MessagePort(source, MSG_ROUTING_CONTROL, extension_id),
                          GET_OPPOSITE_PORT_ID(receiver_port_id), true);
     return;
   }
 
   WebContents* source_contents = tab_util::GetWebContentsByID(
       source_process_id, source_routing_id);
 
   // Include info about the opener's tab (if it was a tab).
   std::string tab_json = "null";
   if (source_contents) {
     scoped_ptr<DictionaryValue> tab_value(
         ExtensionTabUtil::CreateTabValue(source_contents));
     base::JSONWriter::Write(tab_value.get(), &tab_json);
   }
 
   OpenChannelParams params(source, tab_json, receiver, receiver_port_id,
                            extension_id, extension_id, channel_name);
   OpenChannelImpl(params);
 }
 
 bool ExtensionMessageService::OpenChannelImpl(const OpenChannelParams& params) {
   if (!params.source)
     return false;  // Closed while in flight.
 
   if (!params.receiver.process) {
     // Treat it as a disconnect.
-    DispatchOnDisconnect(MessagePort(params.source, MSG_ROUTING_CONTROL),
+    DispatchOnDisconnect(MessagePort(params.source, MSG_ROUTING_CONTROL, ""),
                          GET_OPPOSITE_PORT_ID(params.receiver_port_id), true);
     return false;
   }
 
   // Add extra paranoid CHECKs, since we have crash reports of this being NULL.
   // http://code.google.com/p/chromium/issues/detail?id=19067
   CHECK(params.receiver.process);
 
   MessageChannel* channel(new MessageChannel);
-  channel->opener = MessagePort(params.source, MSG_ROUTING_CONTROL);
+  channel->opener = MessagePort(params.source, MSG_ROUTING_CONTROL,
+                                params.source_extension_id);
   channel->receiver = params.receiver;
-  channel->source_extension_id = params.source_extension_id;
-  channel->target_extension_id = params.target_extension_id;
 
   CHECK(params.receiver.process);
 
   int channel_id = GET_CHANNEL_ID(params.receiver_port_id);
   CHECK(channels_.find(channel_id) == channels_.end());
   channels_[channel_id] = channel;
   pending_channels_.erase(channel_id);
 
   CHECK(params.receiver.process);
 
   // Send the connect event to the receiver.  Give it the opener's port ID (the
   // opener has the opposite port ID).
   DispatchOnConnect(params.receiver, params.receiver_port_id,
                     params.channel_name, params.tab_json,
                     params.source_extension_id, params.target_extension_id);
 
   // Keep both ends of the channel alive until the channel is closed.
-  IncrementLazyKeepaliveCount(channel->opener.process,
-                              channel->source_extension_id);
-  IncrementLazyKeepaliveCount(channel->receiver.process,
-                              channel->target_extension_id);
+  IncrementLazyKeepaliveCount(&channel->opener);
+  IncrementLazyKeepaliveCount(&channel->receiver);
   return true;
 }
 
 void ExtensionMessageService::CloseChannel(int port_id, bool connection_error) {
   // Note: The channel might be gone already, if the other side closed first.
   int channel_id = GET_CHANNEL_ID(port_id);
   MessageChannelMap::iterator it = channels_.find(channel_id);
   if (it == channels_.end()) {
     PendingChannelMap::iterator pending = pending_channels_.find(channel_id);
     if (pending != pending_channels_.end()) {
@@ skipping 14 matching lines @@
 
   // Notify the other side.
   if (notify_other_port) {
     const MessagePort& port = IS_OPENER_PORT_ID(closing_port_id) ?
         channel->receiver : channel->opener;
     DispatchOnDisconnect(port, GET_OPPOSITE_PORT_ID(closing_port_id),
                          connection_error);
   }
 
   // Balance the addrefs in OpenChannelImpl.
-  DecrementLazyKeepaliveCount(channel->opener.process,
-                              channel->source_extension_id);
-  DecrementLazyKeepaliveCount(channel->receiver.process,
-                              channel->target_extension_id);
+  DecrementLazyKeepaliveCount(&channel->opener);
+  DecrementLazyKeepaliveCount(&channel->receiver);
 
   delete channel_iter->second;
   channels_.erase(channel_iter);
 }
 
 void ExtensionMessageService::PostMessageFromRenderer(
     int source_port_id, const std::string& message) {
   int channel_id = GET_CHANNEL_ID(source_port_id);
   MessageChannelMap::iterator iter = channels_.find(channel_id);
   if (iter == channels_.end()) {
@@ skipping 90 matching lines @@
   if (!host)
     return;  // TODO(mpcomplete): notify source of disconnect?
 
   // Re-lookup the source process since it may no longer be valid.
   OpenChannelParams params = params_in;
   params.source = content::RenderProcessHost::FromID(source_process_id);
   if (!params.source)
     return;
 
   params.receiver = MessagePort(host->render_process_host(),
-                                MSG_ROUTING_CONTROL);
+                                MSG_ROUTING_CONTROL,
+                                params.target_extension_id);
   OpenChannelImpl(params);
 }