[libvirt] [PATCHv3 31/43] snapshot: expose halt-after-creation in virsh

[Eric Blake]

Easy enough to emulate even with older servers.

* tools/virsh.c (cmdSnapshotCreate, cmdSnapshotCreateAs): Add
--halt flag.
(vshSnapshotCreate): Emulate halt when flag is unsupported.
* tools/virsh.pod (snapshot-create, snapshot-create-as): Document
it.
---
 tools/virsh.c   |   49 +++++++++++++++++++++++++++++++++++++++++++++++--
 tools/virsh.pod |    9 +++++++--
 2 files changed, 54 insertions(+), 4 deletions(-)

diff --git a/tools/virsh.c b/tools/virsh.c
index 861300d..d4cbbf7 100644
--- a/tools/virsh.c
+++ b/tools/virsh.c
@@ -12105,15 +12105,45 @@ vshSnapshotCreate(vshControl *ctl, virDomainPtr dom, const char *buffer,
 {
     bool ret = false;
     virDomainSnapshotPtr snapshot;
+    bool halt = false;
     char *doc = NULL;
     xmlDocPtr xml = NULL;
     xmlXPathContextPtr ctxt = NULL;
     char *name = NULL;

     snapshot = virDomainSnapshotCreateXML(dom, buffer, flags);
+
+    /* Emulate --halt on older servers.  */
+    if (!snapshot && last_error->code == VIR_ERR_INVALID_ARG &&
+        (flags & VIR_DOMAIN_SNAPSHOT_CREATE_HALT)) {
+        int persistent;
+
+        virFreeError(last_error);
+        last_error = NULL;
+        persistent = virDomainIsPersistent(dom);
+        if (persistent < 0) {
+            virshReportError(ctl);
+            goto cleanup;
+        }
+        if (!persistent) {
+            vshError(ctl, "%s",
+                     _("cannot halt after snapshot of transient domain"));
+            goto cleanup;
+        }
+        if (virDomainIsActive(dom) == 1)
+            halt = true;
+        flags &= ~VIR_DOMAIN_SNAPSHOT_CREATE_HALT;
+        snapshot = virDomainSnapshotCreateXML(dom, buffer, flags);
+    }
+
     if (snapshot == NULL)
         goto cleanup;

+    if (halt && virDomainDestroy(dom) < 0) {
+        virshReportError(ctl);
+        goto cleanup;
+    }
+
     doc = virDomainSnapshotGetXMLDesc(snapshot, 0);
     if (!doc)
         goto cleanup;
@@ -12158,6 +12188,7 @@ static const vshCmdInfo info_snapshot_create[] = {
 static const vshCmdOptDef opts_snapshot_create[] = {
     {"domain", VSH_OT_DATA, VSH_OFLAG_REQ, N_("domain name, id or uuid")},
     {"xmlfile", VSH_OT_DATA, 0, N_("domain snapshot XML")},
+    {"halt", VSH_OT_BOOL, 0, N_("halt domain after snapshot is created")},
     {NULL, 0, 0, NULL}
 };

@@ -12168,6 +12199,10 @@ cmdSnapshotCreate(vshControl *ctl, const vshCmd *cmd)
     bool ret = false;
     const char *from = NULL;
     char *buffer = NULL;
+    int flags = 0;
+
+    if (vshCommandOptBool(cmd, "halt"))
+        flags |= VIR_DOMAIN_SNAPSHOT_CREATE_HALT;

     if (!vshConnectionUsability(ctl, ctl->conn))
         goto cleanup;
@@ -12193,7 +12228,7 @@ cmdSnapshotCreate(vshControl *ctl, const vshCmd *cmd)
         goto cleanup;
     }

-    ret = vshSnapshotCreate(ctl, dom, buffer, 0, from);
+    ret = vshSnapshotCreate(ctl, dom, buffer, flags, from);

 cleanup:
     VIR_FREE(buffer);
@@ -12217,6 +12252,7 @@ static const vshCmdOptDef opts_snapshot_create_as[] = {
     {"name", VSH_OT_DATA, 0, N_("name of snapshot")},
     {"description", VSH_OT_DATA, 0, N_("description of snapshot")},
     {"print-xml", VSH_OT_BOOL, 0, N_("print XML document rather than create")},
+    {"halt", VSH_OT_BOOL, 0, N_("halt domain after snapshot is created")},
     {NULL, 0, 0, NULL}
 };

@@ -12229,6 +12265,10 @@ cmdSnapshotCreateAs(vshControl *ctl, const vshCmd *cmd)
     const char *name = NULL;
     const char *desc = NULL;
     virBuffer buf = VIR_BUFFER_INITIALIZER;
+    int flags = 0;
+
+    if (vshCommandOptBool(cmd, "halt"))
+        flags |= VIR_DOMAIN_SNAPSHOT_CREATE_HALT;

     if (!vshConnectionUsability(ctl, ctl->conn))
         goto cleanup;
@@ -12257,12 +12297,17 @@ cmdSnapshotCreateAs(vshControl *ctl, const vshCmd *cmd)
     }

     if (vshCommandOptBool(cmd, "print-xml")) {
+        if (vshCommandOptBool(cmd, "halt")) {
+            vshError(ctl, "%s",
+                     _("--print-xml and --halt are mutually exclusive"));
+            goto cleanup;
+        }
         vshPrint(ctl, "%s\n",  buffer);
         ret = true;
         goto cleanup;
     }

-    ret = vshSnapshotCreate(ctl, dom, buffer, 0, NULL);
+    ret = vshSnapshotCreate(ctl, dom, buffer, flags, NULL);

 cleanup:
     VIR_FREE(buffer);
diff --git a/tools/virsh.pod b/tools/virsh.pod
index 1cbe5c3..c77b1e4 100644
--- a/tools/virsh.pod
+++ b/tools/virsh.pod
@@ -1591,7 +1591,7 @@ used to represent properties of snapshots.

 =over 4

-=item B<snapshot-create> I<domain> [I<xmlfile>]
+=item B<snapshot-create> I<domain> [I<xmlfile>] [I<--halt>]

 Create a snapshot for domain I<domain> with the properties specified in
 I<xmlfile>.  The only properties settable for a domain snapshot are the
@@ -1599,13 +1599,18 @@ I<xmlfile>.  The only properties settable for a domain snapshot are the
 automatically filled in by libvirt.  If I<xmlfile> is completely omitted,
 then libvirt will choose a value for all fields.

-=item B<snapshot-create-as> I<domain> [I<--print-xml>]
+If I<--halt> is specified, the domain will be left in an inactive state
+after the snapshot is created.
+
+=item B<snapshot-create-as> I<domain> [{I<--print-xml> | I<--halt>}]
 [I<name>] [I<description>]

 Create a snapshot for domain I<domain> with the given <name> and
 <description>; if either value is omitted, libvirt will choose a
 value.  If I<--print-xml> is specified, then XML appropriate for
 I<snapshot-create> is output, rather than actually creating a snapshot.
+Otherwise, if I<--halt> is specified, the domain will be left in an
+inactive state after the snapshot is created.

 =item B<snapshot-current> I<domain> [I<--name>] [I<--security-info>]

-- 
1.7.4.4