Queue callbacks in PluginService::GetPlugins.

content/browser/plugin_loader.cc

+// 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 "content/browser/plugin_loader.h"
+
+#include "base/bind.h"
+#include "content/common/utility_messages.h"
+#include "webkit/plugins/npapi/plugin_list.h"
+
+PluginLoader::PluginLoader() : process_host_(NULL) {
+}
+
+PluginLoader::~PluginLoader() {
+}
+
+void PluginLoader::LoadPlugins(
+    base::MessageLoopProxy* target_loop,
+    const PluginService::GetPluginsCallback& callback) {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
+  callbacks_.push_back(PendingCallback(target_loop, callback));
+  StartLoadingIfNecessary();
+}
+
+void PluginLoader::StartLoadingIfNecessary() {
+  if (process_host_)
+    return;
+
+  process_host_ = new UtilityProcessHost(this, BrowserThread::IO);
+  process_host_->set_no_sandbox(true);
+#if defined(OS_MACOSX)
+  process_host_->set_child_flags(
+      ChildProcessHost::CHILD_ALLOW_HEAP_EXECUTION);
+#endif
+
+  std::vector<FilePath> extra_plugin_paths;
+  std::vector<FilePath> extra_plugin_dirs;
+  std::vector<webkit::WebPluginInfo> internal_plugins;
+  webkit::npapi::PluginList::Singleton()->GetPluginPathListsToLoad(
+      &extra_plugin_paths, &extra_plugin_dirs, &internal_plugins);
+
+  process_host_->Send(new UtilityMsg_LoadPlugins(
+      extra_plugin_paths, extra_plugin_dirs, internal_plugins));
+}
+
+bool PluginLoader::OnMessageReceived(const IPC::Message& message) {
+  bool handled = true;
+  IPC_BEGIN_MESSAGE_MAP(PluginLoader, message)
+    IPC_MESSAGE_HANDLER(UtilityHostMsg_LoadedPlugins, OnGotPlugins)
+    IPC_MESSAGE_UNHANDLED(handled = false)
+  IPC_END_MESSAGE_MAP()
+  return handled;
+}
+
+void PluginLoader::OnProcessCrashed(int exit_code) {
+  LOG(ERROR) << "Out-of-process plugin loader crashed with code " << exit_code
+             << ". You will have no plugins!";
+  // Don't leave callers hanging.
+  OnGotPlugins(std::vector<webkit::WebPluginInfo>());
+}
+
+PluginLoader::PendingCallback::PendingCallback(
+    scoped_refptr<base::MessageLoopProxy> loop,
+    const PluginService::GetPluginsCallback& callback)
+        : target_loop(loop),
+          callback(callback) {}
+
+PluginLoader::PendingCallback::~PendingCallback() {}
+
+void PluginLoader::OnGotPlugins(
+    const std::vector<webkit::WebPluginInfo>& plugins) {
+  webkit::npapi::PluginList::Singleton()->SetPlugins(plugins);
+  for (size_t i = 0; i < callbacks_.size(); ++i) {
+    callbacks_[i].target_loop->PostTask(FROM_HERE,
+        base::Bind(callbacks_[i].callback, plugins));
+  }
+
+  // Reset our state.
+  process_host_ = NULL;
+  callbacks_.clear();
+}