[libvirt] [PATCH 3/4] snapshot: expose location through virsh snapshot-info

[Eric Blake]

Now that we can filter on this information, we should also make
it easy to get at.

* tools/virsh-snapshot.c (cmdSnapshotInfo): Add another output
row.
---
 tools/virsh-snapshot.c | 32 +++++++++++++++++++++++++++-----
 1 file changed, 27 insertions(+), 5 deletions(-)

diff --git a/tools/virsh-snapshot.c b/tools/virsh-snapshot.c
index d5c71be..da1e75f 100644
--- a/tools/virsh-snapshot.c
+++ b/tools/virsh-snapshot.c
@@ -797,7 +797,8 @@ cmdSnapshotInfo(vshControl *ctl, const vshCmd *cmd)
     virDomainSnapshotPtr snapshot = NULL;
     const char *name;
     char *doc = NULL;
-    char *tmp;
+    char *state;
+    bool internal;
     char *parent = NULL;
     bool ret = false;
     int count;
@@ -839,15 +840,36 @@ cmdSnapshotInfo(vshControl *ctl, const vshCmd *cmd)
     if (!doc)
         goto cleanup;

-    tmp = strstr(doc, "<state>");
-    if (!tmp) {
+    state = strstr(doc, "<state>");
+    if (!state) {
         vshError(ctl, "%s",
                  _("unexpected problem reading snapshot xml"));
         goto cleanup;
     }
-    tmp += strlen("<state>");
+    state += strlen("<state>");
     vshPrint(ctl, "%-15s %.*s\n", _("State:"),
-             (int) (strchr(tmp, '<') - tmp), tmp);
+             (int) (strchr(state, '<') - state), state);
+
+    /* In addition to state, location is useful.  If the snapshot has
+     * a <memory> element, then the existence of snapshot='external'
+     * prior to <domain> is the deciding factor; for snapshots
+     * created prior to 1.0.1, a state of disk-only is the only
+     * external snapshot.  */
+    if (strstr(state, "<memory")) {
+        char *domain = strstr(state, "<domain");
+
+        if (!domain) {
+            vshError(ctl, "%s",
+                     _("unexpected problem reading snapshot xml"));
+            goto cleanup;
+        }
+        internal = !memmem(state, domain - state, "snapshot='external'",
+                           strlen("snapshot='external'"));
+    } else {
+        internal = !STRPREFIX(state, "disk-snapshot");
+    }
+    vshPrint(ctl, "%-15s %s\n", _("Location:"),
+             internal ? _("internal") : _("external"));

     if (vshGetSnapshotParent(ctl, snapshot, &parent) < 0)
         goto cleanup;
-- 
1.7.11.7