Host extensions

remoting/host/chromoting_host.cc

Index: remoting/host/chromoting_host.cc
diff --git a/remoting/host/chromoting_host.cc b/remoting/host/chromoting_host.cc
index ef2ea19729cbfa0db13c4103320406a72189d06e..279b6480c6bdbb397e3dd0616ddf1c2606b24ab4 100644
--- a/remoting/host/chromoting_host.cc
+++ b/remoting/host/chromoting_host.cc
@@ -141,6 +141,10 @@ void ChromotingHost::RemoveStatusObserver(HostStatusObserver* observer) {
   status_observers_.RemoveObserver(observer);
 }
 
+void ChromotingHost::AddExtension(scoped_ptr<HostExtension> extension) {
+  extensions_.push_back(extension.release());
+}
+
 void ChromotingHost::RejectAuthenticatingClient() {
   DCHECK(authenticating_client_);
   reject_authenticating_client_ = true;
@@ -209,6 +213,12 @@ bool ChromotingHost::OnSessionAuthenticated(ClientSession* client) {
   // Disconnects above must have destroyed all other clients.
   DCHECK_EQ(clients_.size(), 1U);
 
+  // Registers capabilities provided by host extensions.
+  for (HostExtensionList::iterator extension = extensions_.begin();
+       extension != extensions_.end(); ++extension) {
+    client->AddHostCapabilities((*extension)->GetCapabilities());

[Wez, 2014/05/28 23:03:41]

Do you really need to do this here? Could it wait until OnClientCapabilities, so
that you can derive the capabilities list from the list of extensions that you
have actually added to the ClientSession?

[Wez, 2014/05/28 23:03:41]

If not then it would seem cleaner to have SetHostCapabilities(), and have the
host collate the list and pass it once, rather than having the ClientSession
accumulate the list.

[dcaiafa, 2014/05/29 00:03:16]

We need to send the host capabilities to the client before it can reply with its
capabilities - so we need to compile the host capabilities before
OnClientCapabilities is called.

[dcaiafa, 2014/05/29 00:03:16]

As you mentioned in the comment's message, AddHostCapabilities is also used to
compile capabilities from DesktopEnvironment.

+  }
+
   // Notify observers that there is at least one authenticated client.
   const std::string& jid = client->client_jid();
 
@@ -230,6 +240,19 @@ void ChromotingHost::OnSessionChannelsConnected(ClientSession* client) {
                     OnClientConnected(client->client_jid()));
 }
 
+void ChromotingHost::OnClientCapabilities(ClientSession* client) {
+  DCHECK(CalledOnValidThread());
+
+  // Create extension sessions from each registered extension for this client.
+  for (HostExtensionList::iterator extension = extensions_.begin();
+       extension != extensions_.end(); ++extension) {
+    scoped_ptr<HostExtensionSession> extension_session =
+        (*extension)->CreateExtensionSession(client);
+    if (extension_session)
+      client->AddExtensionSession(extension_session.Pass());
+  }
+}
+
 void ChromotingHost::OnSessionAuthenticationFailed(ClientSession* client) {
   DCHECK(CalledOnValidThread());