daemon: Unlink unix socket paths on shutdown

This patch introduces a internal RPC API "virNetServerClose", which
is standalone with "virNetServerFree".  it closes all the socket fds,
and unlinks the unix socket paths, regardless of whether the socket
is still referenced or not.

This is to address regression bug:
https://bugzilla.redhat.com/show_bug.cgi?id=725702

daemon/libvirtd.c

@@ -1558,6 +1558,7 @@ int main(int argc, char **argv) {
 cleanup:
     virNetServerProgramFree(remoteProgram);
     virNetServerProgramFree(qemuProgram);
+    virNetServerClose(srv);
     virNetServerFree(srv);
     if (statuswrite != -1) {
         if (ret != 0) {

src/rpc/virnetserver.c

@@ -798,3 +798,19 @@ void virNetServerFree(virNetServerPtr srv)
     virMutexDestroy(&srv->lock);
     VIR_FREE(srv);
 }
+
+void virNetServerClose(virNetServerPtr srv)
+{
+    int i;
+
+    if (!srv)
+        return;
+
+    virNetServerLock(srv);
+
+    for (i = 0; i < srv->nservices; i++) {
+        virNetServerServiceClose(srv->services[i]);
+    }
+
+    virNetServerUnlock(srv);
+}

src/rpc/virnetserver.h

@@ -85,5 +85,6 @@ void virNetServerQuit(virNetServerPtr srv);
 
 void virNetServerFree(virNetServerPtr srv);
 
+void virNetServerClose(virNetServerPtr srv);
 
 #endif

src/rpc/virnetserverservice.c

@@ -280,3 +280,15 @@ void virNetServerServiceToggle(virNetServerServicePtr svc,
                                      VIR_EVENT_HANDLE_READABLE :
                                      0);
 }
+
+void virNetServerServiceClose(virNetServerServicePtr svc)
+{
+    int i;
+
+    if (!svc)
+        return;
+
+    for (i = 0; i < svc->nsocks; i++) {
+        virNetSocketClose(svc->socks[i]);
+    }
+}

src/rpc/virnetserverservice.h

@@ -66,4 +66,6 @@ void virNetServerServiceFree(virNetServerServicePtr svc);
 void virNetServerServiceToggle(virNetServerServicePtr svc,
                                bool enabled);
 
+void virNetServerServiceClose(virNetServerServicePtr svc);
+
 #endif

src/rpc/virnetsocket.c

@@ -1222,3 +1222,25 @@ void virNetSocketRemoveIOCallback(virNetSocketPtr sock)
 
     virMutexUnlock(&sock->lock);
 }
+
+void virNetSocketClose(virNetSocketPtr sock)
+{
+    if (!sock)
+        return;
+
+    virMutexLock(&sock->lock);
+
+    VIR_FORCE_CLOSE(sock->fd);
+
+#ifdef HAVE_SYS_UN_H
+    /* If a server socket, then unlink UNIX path */
+    if (!sock->client &&
+        sock->localAddr.data.sa.sa_family == AF_UNIX &&
+        sock->localAddr.data.un.sun_path[0] != '\0') {
+        if (unlink(sock->localAddr.data.un.sun_path) == 0)
+            sock->localAddr.data.un.sun_path[0] = '\0';
+    }
+#endif
+
+    virMutexUnlock(&sock->lock);
+}

src/rpc/virnetsocket.h

@@ -118,6 +118,7 @@ void virNetSocketUpdateIOCallback(virNetSocketPtr sock,
 
 void virNetSocketRemoveIOCallback(virNetSocketPtr sock);
 
+void virNetSocketClose(virNetSocketPtr sock);
 
 
 #endif /* __VIR_NET_SOCKET_H__ */