[Qemu-devel] [PATCH 4/5] monitor: Port do_info_balloon() to QObject

[Luiz Capitulino <lcapitulino@redhat.com>]

do_info_balloon() returns 0 on success or -1 when the 'balloon'
value could not be queried.

The returned data is always a QString.

This also introduces monitor_print_qobject(), which can be
used as a standard way to print QObjects in the user protocol
format.

Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
---
 monitor.c |   41 +++++++++++++++++++++++++++++++++--------
 1 files changed, 33 insertions(+), 8 deletions(-)

diff --git a/monitor.c b/monitor.c
index f9f3cbd..545833d 100644
--- a/monitor.c
+++ b/monitor.c
@@ -213,6 +213,22 @@ static void monitor_print_nothing(Monitor *mon, const QObject *data)
     return;
 }
 
+static void monitor_print_qobject(Monitor *mon, const QObject *data)
+{
+    switch (qobject_type(data)) {
+        case QTYPE_QSTRING:
+            monitor_printf(mon, "%s",qstring_get_str(qobject_to_qstring(data)));
+            break;
+        case QTYPE_QINT:
+            monitor_printf(mon, "%lu", qint_get_int(qobject_to_qint(data)));
+            break;
+        default:
+            monitor_printf(mon, "ERROR: unsupported type: %d\n",
+                                                        qobject_type(data));
+            break;
+    }
+}
+
 static int compare_cmd(const char *name, const char *list)
 {
     const char *p, *pstart;
@@ -1586,18 +1602,27 @@ static void do_balloon(Monitor *mon, const QDict *qdict)
     qemu_balloon(target << 20);
 }
 
-static void do_info_balloon(Monitor *mon)
+static int do_info_balloon(Monitor *mon, QObject **ret_data)
 {
+    QString *qs;
     ram_addr_t actual;
+    int ret = -1;
 
     actual = qemu_balloon_status();
-    if (kvm_enabled() && !kvm_has_sync_mmu())
-        monitor_printf(mon, "Using KVM without synchronous MMU, "
+    if (kvm_enabled() && !kvm_has_sync_mmu()) {
+        qs = qstring_from_str("Using KVM without synchronous MMU, "
                        "ballooning disabled\n");
-    else if (actual == 0)
-        monitor_printf(mon, "Ballooning not activated in VM\n");
-    else
-        monitor_printf(mon, "balloon: actual=%d\n", (int)(actual >> 20));
+    } else if (actual == 0) {
+        qs = qstring_from_str("Ballooning not activated in VM\n");
+    } else {
+        char buf[128];
+        sprintf(buf, "balloon: actual=%d\n", (int)(actual >> 20));
+        qs = qstring_from_str(buf);
+        ret = 0;
+    }
+
+    *ret_data = QOBJECT(qs);
+    return ret;
 }
 
 static qemu_acl *find_acl(Monitor *mon, const char *name)
@@ -1898,7 +1923,7 @@ static const mon_cmd_t info_cmds[] = {
       "", "show user network stack connection states", },
 #endif
     { "migrate", "", do_info_migrate, NULL, "", "show migration status" },
-    { "balloon", "", do_info_balloon, NULL,
+    { "balloon", "", do_info_balloon, monitor_print_qobject,
       "", "show balloon information" },
     { "qtree", "", do_info_qtree, NULL,
       "", "show device tree" },
-- 
1.6.4.2.253.g0b1fac