[libvirt] [PATCH 4/4] Add an explicit virNetClientClose method

[Daniel P. Berrange]

From: "Daniel P. Berrange" <berrange at redhat.com>

Since the I/O callback registered against virNetSocket will
hold a reference on the virNetClient, we can't rely on the
virNetClientFree to be able to close the network connection.
The last reference will only go away when the event callback
fires (likely due to EOF from the server).

This is sub-optimal and can potentially cause a leak of the
virNetClient object if the server were to not explicitly
close the socket itself

* src/remote/remote_driver.c: Explicitly close the client
  object when disconnecting
* src/rpc/virnetclient.c, src/rpc/virnetclient.h: Add a
  virNetClientClose method
---
 src/remote/remote_driver.c |    2 ++
 src/rpc/virnetclient.c     |   22 +++++++++++++++++++++-
 src/rpc/virnetclient.h     |    1 +
 3 files changed, 24 insertions(+), 1 deletions(-)

diff --git a/src/remote/remote_driver.c b/src/remote/remote_driver.c
index c2f8bbd..6bae353 100644
--- a/src/remote/remote_driver.c
+++ b/src/remote/remote_driver.c
@@ -684,6 +684,7 @@ doRemoteOpen (virConnectPtr conn,
         free_qparam_set (vars);
 
  failed:
+    virNetClientClose(priv->client);
     virNetClientFree(priv->client);
     priv->client = NULL;
 
@@ -834,6 +835,7 @@ doRemoteClose (virConnectPtr conn, struct private_data *priv)
 
     virNetTLSContextFree(priv->tls);
     priv->tls = NULL;
+    virNetClientClose(priv->client);
     virNetClientFree(priv->client);
     priv->client = NULL;
     virNetClientProgramFree(priv->remoteProgram);
diff --git a/src/rpc/virnetclient.c b/src/rpc/virnetclient.c
index 27542a5..dfc4ed9 100644
--- a/src/rpc/virnetclient.c
+++ b/src/rpc/virnetclient.c
@@ -255,7 +255,8 @@ void virNetClientFree(virNetClientPtr client)
 
     VIR_FREE(client->hostname);
 
-    virNetSocketRemoveIOCallback(client->sock);
+    if (client->sock)
+        virNetSocketRemoveIOCallback(client->sock);
     virNetSocketFree(client->sock);
     virNetTLSSessionFree(client->tls);
 #if HAVE_SASL
@@ -268,6 +269,22 @@ void virNetClientFree(virNetClientPtr client)
 }
 
 
+void virNetClientClose(virNetClientPtr client)
+{
+    virNetClientLock(client);
+    virNetSocketRemoveIOCallback(client->sock);
+    virNetSocketFree(client->sock);
+    client->sock = NULL;
+    virNetTLSSessionFree(client->tls);
+    client->tls = NULL;
+#if HAVE_SASL
+    virNetSASLSessionFree(client->sasl);
+    client->sasl = NULL;
+#endif
+    virNetClientUnlock(client);
+}
+
+
 #if HAVE_SASL
 void virNetClientSetSASLSession(virNetClientPtr client,
                                 virNetSASLSessionPtr sasl)
@@ -1118,6 +1135,9 @@ void virNetClientIncomingEvent(virNetSocketPtr sock,
 
     virNetClientLock(client);
 
+    if (!client->sock)
+        goto done;
+
     /* This should be impossible, but it doesn't hurt to check */
     if (client->waitDispatch)
         goto done;
diff --git a/src/rpc/virnetclient.h b/src/rpc/virnetclient.h
index 6acdf50..a0983bc 100644
--- a/src/rpc/virnetclient.h
+++ b/src/rpc/virnetclient.h
@@ -81,5 +81,6 @@ const char *virNetClientRemoteAddrString(virNetClientPtr client);
 int virNetClientGetTLSKeySize(virNetClientPtr client);
 
 void virNetClientFree(virNetClientPtr client);
+void virNetClientClose(virNetClientPtr client);
 
 #endif /* __VIR_NET_CLIENT_H__ */
-- 
1.7.6