[Qemu-devel] [PATCH v2] monitor: Really show snapshot information about all devices

[Miguel Di Ciurcio Filho <miguel.filho@gmail.com>]

The 'info snapshots' monitor command does not show snapshot information from all
available block devices.

Usage example:
$ qemu -hda disk1.qcow2 -hdb disk2.qcow2

(qemu) info snapshots
Snapshot devices: ide0-hd0
Snapshot list (from ide0-hd0):
ID        TAG                 VM SIZE                DATE       VM CLOCK
1                                1.5M 2010-05-26 21:51:02   00:00:03.263
2                                1.5M 2010-05-26 21:51:09   00:00:08.844
3                                1.5M 2010-05-26 21:51:24   00:00:23.274
4                                1.5M 2010-05-26 21:53:17   00:00:03.595

In the above case, disk2.qcow2 has snapshot information, but it is not being
shown. Only the first device is always shown.

This patch updates the do_info_snapshots() function do correctly show snapshot
information about all available block devices.

New output:
(qemu) info snapshots
Snapshot list from ide0-hd0 (VM state image):
ID        TAG                 VM SIZE                DATE       VM CLOCK
1                                1.5M 2010-05-26 21:51:02   00:00:03.263
2                                1.5M 2010-05-26 21:51:09   00:00:08.844
3                                1.5M 2010-05-26 21:51:24   00:00:23.274
4                                1.5M 2010-05-26 21:53:17   00:00:03.595

Snapshot list from ide0-hd1:
ID        TAG                 VM SIZE                DATE       VM CLOCK
1                                   0 2010-05-26 21:51:02   00:00:03.263
2                                   0 2010-05-26 21:51:09   00:00:08.844
3                                   0 2010-05-26 21:51:24   00:00:23.274
4                                   0 2010-05-26 21:53:17   00:00:03.595

changelog
---------
v1 -> v2
- Added support to identify the device elected to save the VM's state.

Signed-off-by: Miguel Di Ciurcio Filho <miguel.filho@gmail.com>
---
 savevm.c |   57 ++++++++++++++++++++++++++++++++-------------------------
 1 files changed, 32 insertions(+), 25 deletions(-)

diff --git a/savevm.c b/savevm.c
index 20354a8..5bc5fcd 100644
--- a/savevm.c
+++ b/savevm.c
@@ -1858,37 +1858,44 @@ void do_delvm(Monitor *mon, const QDict *qdict)
 
 void do_info_snapshots(Monitor *mon)
 {
-    BlockDriverState *bs, *bs1;
-    QEMUSnapshotInfo *sn_tab, *sn;
+    BlockDriverState *bs, *bs_vm_state;
+    QEMUSnapshotInfo *sn_tab;
     int nb_sns, i;
     char buf[256];
 
-    bs = get_bs_snapshots();
-    if (!bs) {
+    bs_vm_state = get_bs_snapshots();
+    if (!bs_vm_state) {
         monitor_printf(mon, "No available block device supports snapshots\n");
         return;
     }
-    monitor_printf(mon, "Snapshot devices:");
-    bs1 = NULL;
-    while ((bs1 = bdrv_next(bs1))) {
-        if (bdrv_can_snapshot(bs1)) {
-            if (bs == bs1)
-                monitor_printf(mon, " %s", bdrv_get_device_name(bs1));
-        }
-    }
-    monitor_printf(mon, "\n");
 
-    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, "Snapshot list (from %s):\n",
-                   bdrv_get_device_name(bs));
-    monitor_printf(mon, "%s\n", bdrv_snapshot_dump(buf, sizeof(buf), NULL));
-    for(i = 0; i < nb_sns; i++) {
-        sn = &sn_tab[i];
-        monitor_printf(mon, "%s\n", bdrv_snapshot_dump(buf, sizeof(buf), sn));
+    bs = NULL;
+    while ((bs = bdrv_next(bs))) {
+        if (bdrv_can_snapshot(bs)) {
+            monitor_printf(mon, "Snapshot list from %s",
+                           bdrv_get_device_name(bs));
+
+            if (bs == bs_vm_state) {
+                monitor_printf(mon, " (VM state image):\n");
+            } else {
+                monitor_printf(mon, ":\n");
+            }
+
+            monitor_printf(mon, "%s\n", bdrv_snapshot_dump(buf, sizeof(buf), NULL));
+
+            nb_sns = bdrv_snapshot_list(bs, &sn_tab);
+            if (nb_sns < 0) {
+                monitor_printf(mon, "bdrv_snapshot_list: error %d\n", nb_sns);
+                continue;
+            }
+
+            for (i = 0; i < nb_sns; i++) {
+                monitor_printf(mon, "%s\n", bdrv_snapshot_dump(buf, sizeof(buf),
+                    &sn_tab[i]));
+            }
+
+            qemu_free(sn_tab);
+            monitor_printf(mon, "\n");
+        }
     }
-    qemu_free(sn_tab);
 }
-- 
1.7.1