[Qemu-devel] [PATCH V2 10/11] hmp: retrieve info from qmp for snapshot info

[Wenchao Xia <xiawenc@linux.vnet.ibm.com>]

  With this patch, hmp command info snapshot simply call a block
layer funtion which will return a qmp object, and then translate
it in monitor console. Now snapshot info retrieving code in qemu
and qemu-tool are merged by calling same block layer function,
and then they just translate the qmp to stdout or monitor.

Note:
  This patch need previous hmp extention patch which enable
info sub command take qdict * as paramter.

v2:
  free SnapshotInfoList after usage.

Signed-off-by: Wenchao Xia <xiawenc@linux.vnet.ibm.com>
---
 savevm.c |   84 +++++++++++++++++++++++++-------------------------------------
 1 files changed, 34 insertions(+), 50 deletions(-)

diff --git a/savevm.c b/savevm.c
index 9af2605..cabdcb6 100644
--- a/savevm.c
+++ b/savevm.c
@@ -48,6 +48,7 @@
 #include "qmp-commands.h"
 #include "trace.h"
 #include "qemu/bitops.h"
+#include "hmp.h"
 
 #define SELF_ANNOUNCE_ROUNDS 5
 
@@ -2311,68 +2312,51 @@ void do_delvm(Monitor *mon, const QDict *qdict)
     }
 }
 
-void do_info_snapshots(Monitor *mon, const QDict *qdict)
+/* assume list is valid */
+static void monitor_dump_snapshotinfolist(Monitor *mon, SnapshotInfoList *list)
 {
-    BlockDriverState *bs, *bs1;
-    QEMUSnapshotInfo *sn_tab, *sn, s, *sn_info = &s;
-    int nb_sns, i, ret, available;
-    int total;
-    int *available_snapshots;
+    SnapshotInfoList *elem;
     char buf[256];
 
-    bs = bdrv_snapshots();
-    if (!bs) {
-        monitor_printf(mon, "No available block device supports snapshots\n");
-        return;
-    }
-
-    nb_sns = bdrv_snapshot_list(bs, &sn_tab);
-    if (nb_sns < 0) {
-        monitor_printf(mon, "bdrv_snapshot_list: error %d\n", nb_sns);
-        return;
-    }
+    monitor_printf(mon, "%s\n", bdrv_snapshot_dump(buf, sizeof(buf), NULL));
 
-    if (nb_sns == 0) {
-        monitor_printf(mon, "There is no snapshot available.\n");
-        return;
+    for (elem = list; elem; elem = elem->next) {
+        QEMUSnapshotInfo sn = {
+            .vm_state_size = elem->value->vm_state_size,
+            .date_sec = elem->value->date_sec,
+            .date_nsec = elem->value->date_nsec,
+            .vm_clock_nsec = elem->value->vm_clock_sec * 1000000000ULL +
+                             elem->value->vm_clock_nsec,
+        };
+        pstrcpy(sn.id_str, sizeof(sn.id_str), elem->value->id);
+        pstrcpy(sn.name, sizeof(sn.name), elem->value->name);
+        monitor_printf(mon, "%s\n", bdrv_snapshot_dump(buf, sizeof(buf), &sn));
     }
+}
 
-    available_snapshots = g_malloc0(sizeof(int) * nb_sns);
-    total = 0;
-    for (i = 0; i < nb_sns; i++) {
-        sn = &sn_tab[i];
-        available = 1;
-        bs1 = NULL;
-
-        while ((bs1 = bdrv_next(bs1))) {
-            if (bdrv_can_snapshot(bs1) && bs1 != bs) {
-                ret = bdrv_snapshot_find(bs1, sn_info, sn->id_str);
-                if (ret < 0) {
-                    available = 0;
-                    break;
-                }
-            }
-        }
+static void do_info_snapshots_vm(Monitor *mon)
+{
+    Error *err = NULL;
+    SnapshotInfoList *list;
 
-        if (available) {
-            available_snapshots[total] = i;
-            total++;
-        }
+    list = qmp_query_snapshots(&err);
+    if (error_is_set(&err)) {
+        hmp_handle_error(mon, &err);
+        return;
     }
-
-    if (total > 0) {
-        monitor_printf(mon, "%s\n", bdrv_snapshot_dump(buf, sizeof(buf), NULL));
-        for (i = 0; i < total; i++) {
-            sn = &sn_tab[available_snapshots[i]];
-            monitor_printf(mon, "%s\n", bdrv_snapshot_dump(buf, sizeof(buf), sn));
-        }
-    } else {
+    if (list == NULL) {
         monitor_printf(mon, "There is no suitable snapshot available\n");
+        return;
     }
 
-    g_free(sn_tab);
-    g_free(available_snapshots);
+    monitor_dump_snapshotinfolist(mon, list);
+    qapi_free_SnapshotInfoList(list);
+    return;
+}
 
+void do_info_snapshots(Monitor *mon, const QDict *qdict)
+{
+    do_info_snapshots_vm(mon);
 }
 
 void vmstate_register_ram(MemoryRegion *mr, DeviceState *dev)
-- 
1.7.1