[libvirt] [EXAMPLE PATCH 12/13] admin: Add virAdmHello function

[Martin Kletzander]

Just one of the simplest functions that returns string "Clients: X"
where X is the number of connected clients to daemon's first
subserver (the original one), so it can be tested using virsh, ipython,
etc.

The subserver is gathered by incrementing its reference
counter (similarly to getting qemu capabilities), so there is no
deadlock with admin subserver in this API.

Here you can see how functions should be named in the client (virAdm*)
and server (adm*).

There is also a parameter @flags that must be 0, which helps testing
proper error propagation into the client.

Signed-off-by: Martin Kletzander <mkletzan at redhat.com>
---
 daemon/admin_server.c           | 23 +++++++++++++++++++++++
 include/libvirt/libvirt-admin.h |  1 +
 po/POTFILES.in                  |  1 +
 src/admin/admin_protocol.x      | 15 ++++++++++++++-
 src/admin_protocol-structs      |  9 +++++++++
 src/libvirt-admin.c             | 26 ++++++++++++++++++++++++++
 src/libvirt_admin.syms          |  1 +
 7 files changed, 75 insertions(+), 1 deletion(-)

diff --git a/daemon/admin_server.c b/daemon/admin_server.c
index 810908b..e722757 100644
--- a/daemon/admin_server.c
+++ b/daemon/admin_server.c
@@ -113,4 +113,27 @@ adminDispatchConnectClose(virNetServerPtr server ATTRIBUTE_UNUSED,
     return 0;
 }

+
+static char *
+admHello(virNetDaemonPtr dmn,
+         unsigned int flags)
+{
+    char *ret = NULL;
+    virNetServerPtr srv = NULL;
+    size_t nclients;
+
+    virCheckFlags(0, NULL);
+
+    if (!(srv = virNetDaemonGetServer(dmn, 0)))
+        return NULL;
+
+    nclients = virNetServerGetNClients(srv);
+    if (virAsprintf(&ret, "Clients: %zu", nclients) < 0)
+        goto cleanup;
+
+ cleanup:
+    virObjectUnref(srv);
+    return ret;
+}
+
 #include "admin_dispatch.h"
diff --git a/include/libvirt/libvirt-admin.h b/include/libvirt/libvirt-admin.h
index b3cfc93..27178b4 100644
--- a/include/libvirt/libvirt-admin.h
+++ b/include/libvirt/libvirt-admin.h
@@ -54,6 +54,7 @@ virAdmConnectPtr virAdmConnectOpen(const char *name, unsigned int flags);
 int virAdmConnectClose(virAdmConnectPtr conn);

 int virAdmConnectRef(virAdmConnectPtr conn);
+char *virAdmHello(virAdmConnectPtr conn, unsigned int flags);

 # ifdef __cplusplus
 }
diff --git a/po/POTFILES.in b/po/POTFILES.in
index 189e2cc..31f03d9 100644
--- a/po/POTFILES.in
+++ b/po/POTFILES.in
@@ -1,3 +1,4 @@
+daemon/admin_dispatch.h
 daemon/admin_server.c
 daemon/libvirtd-config.c
 daemon/libvirtd.c
diff --git a/src/admin/admin_protocol.x b/src/admin/admin_protocol.x
index 63f6a53..03b98ec 100644
--- a/src/admin/admin_protocol.x
+++ b/src/admin/admin_protocol.x
@@ -30,6 +30,14 @@ struct admin_connect_open_args {
     unsigned int flags;
 };

+struct admin_hello_args {
+    unsigned int flags;
+};
+
+struct admin_hello_ret {
+    remote_string greeting;
+};
+

 /* Define the program number, protocol version and procedure numbers here. */
 const ADMIN_PROGRAM = 0x06900690;
@@ -61,5 +69,10 @@ enum admin_procedure {
     /**
      * @generate: client
      */
-    ADMIN_PROC_CONNECT_CLOSE = 2
+    ADMIN_PROC_CONNECT_CLOSE = 2,
+
+    /**
+     * @generate: both
+     */
+    ADMIN_PROC_HELLO = 3
 };
diff --git a/src/admin_protocol-structs b/src/admin_protocol-structs
index bc1d489..7af66ce 100644
--- a/src/admin_protocol-structs
+++ b/src/admin_protocol-structs
@@ -3,7 +3,16 @@ struct admin_connect_open_args {
     unsigned int flags;
 };

+struct admin_hello_args {
+    unsigned int flags;
+};
+
+struct admin_hello_ret {
+    remote_string greeting;
+};
+
 enum admin_procedure {
     ADMIN_PROC_CONNECT_OPEN = 1,
     ADMIN_PROC_CONNECT_CLOSE = 2,
+    ADMIN_PROC_HELLO = 3,
 };
diff --git a/src/libvirt-admin.c b/src/libvirt-admin.c
index 11b6fe3..107e27e 100644
--- a/src/libvirt-admin.c
+++ b/src/libvirt-admin.c
@@ -384,3 +384,29 @@ virAdmConnectRef(virAdmConnectPtr conn)

     return 0;
 }
+
+
+/**
+ * virAdmHello:
+ * @conn: a connection object
+ * @flags: unused, 0 for now
+ *
+ * Testing function.
+ *
+ * Returns the number of connected clients as a string.  Yes, as a
+ * string.  Because it's just for testing.
+ */
+char *
+virAdmHello(virAdmConnectPtr conn,
+            unsigned int flags)
+{
+    char *ret = NULL;
+
+    virResetLastError();
+
+    ret = remoteAdminHello(conn, flags);
+    if (!ret)
+        virDispatchError(NULL);
+
+    return ret;
+}
diff --git a/src/libvirt_admin.syms b/src/libvirt_admin.syms
index ea6a8cc..8d5c3f8 100644
--- a/src/libvirt_admin.syms
+++ b/src/libvirt_admin.syms
@@ -15,4 +15,5 @@ LIBVIRT_ADMIN_1.3.0 {
         virAdmInitialize;
         virAdmConnectOpen;
         virAdmConnectClose;
+        virAdmHello;
 };
--
2.4.0