[DevTools] Make DevTools clients talk directly to DevToolsAgentHost instead of using DevToolsManage…

content/browser/devtools/devtools_agent_host_impl.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 "content/browser/devtools/devtools_agent_host_impl.h"
 
 #include <map>
+#include <vector>
 
 #include "base/basictypes.h"
 #include "base/guid.h"
 #include "base/lazy_instance.h"
 #include "content/browser/devtools/devtools_manager_impl.h"
 #include "content/browser/devtools/forwarding_agent_host.h"
 #include "content/public/browser/browser_thread.h"
+#include "content/public/browser/devtools_manager_delegate.h"
 
 namespace content {
 
 namespace {
 typedef std::map<std::string, DevToolsAgentHostImpl*> Instances;
 base::LazyInstance<Instances>::Leaky g_instances = LAZY_INSTANCE_INITIALIZER;
+
+typedef std::vector<const DevToolsAgentHost::AgentStateCallback*>
+    AgentStateCallbacks;
+base::LazyInstance<AgentStateCallbacks>::Leaky g_callbacks =
+    LAZY_INSTANCE_INITIALIZER;
 }  // namespace
 
 DevToolsAgentHostImpl::DevToolsAgentHostImpl()
-    : close_listener_(NULL),
-      id_(base::GenerateGUID()) {
+    : id_(base::GenerateGUID()),
+      client_(NULL) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
   g_instances.Get()[id_] = this;
 }
 
 DevToolsAgentHostImpl::~DevToolsAgentHostImpl() {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
   g_instances.Get().erase(g_instances.Get().find(id_));
 }
 
 //static
 scoped_refptr<DevToolsAgentHost> DevToolsAgentHost::GetForId(
     const std::string& id) {
   if (g_instances == NULL)
     return NULL;
   Instances::iterator it = g_instances.Get().find(id);
   if (it == g_instances.Get().end())
     return NULL;
   return it->second;
 }
 
 //static
 scoped_refptr<DevToolsAgentHost> DevToolsAgentHost::Create(
     DevToolsExternalAgentProxyDelegate* delegate) {
   return new ForwardingAgentHost(delegate);
 }
 
+void DevToolsAgentHostImpl::AttachClient(Client* client) {
+  if (client_) {
+    client_->AgentHostDetached(this, REPLACED_WITH_ANOTHER_CLIENT);
+    NotifyCallbacks(this, false);
+    Detach();
+  } else {
+    // While client is attached, we should not die.
+    AddRef(); // Balanced in DetachInternal.

[pfeldman, 2014/08/07 15:40:30]

Why is this necessary? Clients will hold agents to send them messages anyways.

[dgozman, 2014/08/07 16:51:52]

Done.

+    DevToolsManagerImpl::GetInstance()->OnClientAttached();
+  }
+  client_ = client;
+  NotifyCallbacks(this, true);
+  Attach();
+}
+
+void DevToolsAgentHostImpl::DetachClient() {
+  DetachInternal(DETACHED_BY_CLIENT, true);
+}
+
 bool DevToolsAgentHostImpl::IsAttached() {
-  return !!DevToolsManagerImpl::GetInstance()->GetDevToolsClientHostFor(this);
+  return !!client_;
 }
 
 void DevToolsAgentHostImpl::InspectElement(int x, int y) {
 }
 
 std::string DevToolsAgentHostImpl::GetId() {
   return id_;
 }
 
 RenderViewHost* DevToolsAgentHostImpl::GetRenderViewHost() {
   return NULL;
 }
 
 void DevToolsAgentHostImpl::DisconnectRenderViewHost() {}
 
 void DevToolsAgentHostImpl::ConnectRenderViewHost(RenderViewHost* rvh) {}
 
 bool DevToolsAgentHostImpl::IsWorker() const {
   return false;
 }
 
-void DevToolsAgentHostImpl::NotifyCloseListener() {
-  if (close_listener_) {
-    scoped_refptr<DevToolsAgentHostImpl> protect(this);
-    close_listener_->AgentHostClosing(this);
-    close_listener_ = NULL;
+void DevToolsAgentHostImpl::HostClosed() {
+  // Don't call Detach, since host is already gone - nothing to detach from.
+  DetachInternal(HOST_CLOSED, false);
+}
+
+void DevToolsAgentHostImpl::SendMessageToClient(const std::string& message) {
+  if (!client_)
+    return;
+  client_->SendMessageFromAgentHost(this, message);
+}
+
+void DevToolsAgentHostImpl::DetachInternal(
+    DetachReason reason, bool need_detach) {

[pfeldman, 2014/08/07 15:40:30]

This seems error-prone. The reason should be enough to make this decision.

[dgozman, 2014/08/07 16:51:52]

Done.

+  if (!client_)
+    return;
+
+  client_->AgentHostDetached(this, reason);
+  client_ = NULL;
+  NotifyCallbacks(this, false);
+  if (need_detach)
+    Detach();
+  Release(); // Balanced in AttachClient.
+  DevToolsManagerImpl::GetInstance()->OnClientDetached();
+}
+
+// static
+void DevToolsAgentHost::DetachAllClients() {
+  if (g_instances == NULL)
+    return;
+
+  // Make a copy, since detaching may lead to agent destruction, which
+  // removes it from the instances.
+  Instances copy = g_instances.Get();
+  for (Instances::iterator it(copy.begin()); it != copy.end(); ++it) {
+    it->second->DetachInternal(HOST_CLOSED, true);
   }
 }
 
+// static
+void DevToolsAgentHost::AddAgentStateCallback(
+    const AgentStateCallback& callback) {
+  g_callbacks.Get().push_back(&callback);
+}
+
+// static
+void DevToolsAgentHost::RemoveAgentStateCallback(
+    const AgentStateCallback& callback) {
+  if (g_callbacks == NULL)
+    return;
+
+  AgentStateCallbacks* callbacks_ = g_callbacks.Pointer();
+  AgentStateCallbacks::iterator it =
+      std::find(callbacks_->begin(), callbacks_->end(), &callback);
+  DCHECK(it != callbacks_->end());
+  callbacks_->erase(it);
+}
+
+// static
+void DevToolsAgentHostImpl::NotifyCallbacks(
+    DevToolsAgentHostImpl* agent_host, bool attached) {
+  AgentStateCallbacks copy = g_callbacks.Get();
+  DevToolsManagerImpl* manager = DevToolsManagerImpl::GetInstance();
+  if (manager->delegate())
+    manager->delegate()->DevToolsAgentStateChanged(agent_host, attached);
+  for (AgentStateCallbacks::iterator it = copy.begin(); it != copy.end(); ++it)
+     (*it)->Run(agent_host, attached);
+}
+
+void DevToolsAgentHostImpl::Inspect(BrowserContext* browser_context) {
+  DevToolsManagerImpl* manager = DevToolsManagerImpl::GetInstance();
+  if (manager->delegate())
+    manager->delegate()->Inspect(browser_context, this);
+}
+
 }  // namespace content