[Libguestfs] [libnbd PATCH 2/2] info: Expose description in list mode

[Eric Blake]

Exposing a description in single mode is harder: we'd have to request
NBD_INFO_DESCRIPTION during NBD_OPT_GO.  For now, the API only
supports descriptions in list mode.
---
 info/info-list-json.sh |  3 ++-
 info/info-list.sh      |  3 ++-
 info/nbdinfo.c         | 21 ++++++++++++++++-----
 3 files changed, 20 insertions(+), 7 deletions(-)

diff --git a/info/info-list-json.sh b/info/info-list-json.sh
index 3845875..af29064 100755
--- a/info/info-list-json.sh
+++ b/info/info-list-json.sh
@@ -33,7 +33,7 @@ cleanup_fn rm -f $img $out $pid $sock
 rm -f $img $out $pid $sock

 truncate -s 1M $img
-qemu-nbd -t --socket=$sock --pid-file=$pid -x "hello" $img &
+qemu-nbd -t --socket=$sock --pid-file=$pid -x "hello" -D "world" $img &
 cleanup_fn kill $!

 # Wait for qemu-nbd to start up.
@@ -52,4 +52,5 @@ $VG nbdinfo "nbd+unix://?socket=$sock" --list --json > $out
 cat $out

 grep '"export-name": "hello"' $out
+grep '"description": "world"' $out
 grep '"export-size": 1048576' $out
diff --git a/info/info-list.sh b/info/info-list.sh
index c30f258..d51a6ff 100755
--- a/info/info-list.sh
+++ b/info/info-list.sh
@@ -33,7 +33,7 @@ cleanup_fn rm -f $img $out $pid $sock
 rm -f $img $out $pid $sock

 truncate -s 1M $img
-qemu-nbd -t --socket=$sock --pid-file=$pid -x "hello" $img &
+qemu-nbd -t --socket=$sock --pid-file=$pid -x "hello" -D "world" $img &
 cleanup_fn kill $!

 # Wait for qemu-nbd to start up.
@@ -52,4 +52,5 @@ $VG nbdinfo "nbd+unix://?socket=$sock" --list > $out
 cat $out

 grep 'export="hello":' $out
+grep 'description: world' $out
 grep 'export-size: 1048576' $out
diff --git a/info/nbdinfo.c b/info/nbdinfo.c
index 49c97be..1aca548 100644
--- a/info/nbdinfo.c
+++ b/info/nbdinfo.c
@@ -37,7 +37,7 @@ static bool probe_content, content_flag, no_content_flag;
 static bool json_output = false;
 static bool size_only = false;

-static void list_one_export (struct nbd_handle *nbd);
+static void list_one_export (struct nbd_handle *nbd, const char *desc);
 static void list_all_exports (struct nbd_handle *nbd1, const char *uri);
 static void print_json_string (const char *);
 static char *get_content (struct nbd_handle *, int64_t size);
@@ -243,7 +243,8 @@ main (int argc, char *argv[])
     }

     if (!list_all)
-      list_one_export (nbd);
+      /* XXX We would need libnbd to request NBD_INFO_DESCRIPTION */
+      list_one_export (nbd, NULL);
     else
       list_all_exports (nbd, argv[optind]);

@@ -256,7 +257,7 @@ main (int argc, char *argv[])
 }

 static void
-list_one_export (struct nbd_handle *nbd)
+list_one_export (struct nbd_handle *nbd, const char *desc)
 {
   int64_t size;
   char *export_name = NULL;
@@ -298,6 +299,8 @@ list_one_export (struct nbd_handle *nbd)
     /* Might as well use the JSON function to get an escaped string here ... */
     print_json_string (export_name);
     printf (":\n");
+    if (desc && *desc)
+      printf ("\tdescription: %s\n", desc);
     printf ("\texport-size: %" PRIi64 "\n", size);
     if (content)
       printf ("\tcontent: %s\n", content);
@@ -336,6 +339,12 @@ list_one_export (struct nbd_handle *nbd)
     print_json_string (export_name);
     printf (",\n");

+    if (desc && *desc) {
+      printf ("\t\"description\": ");
+      print_json_string (desc);
+      printf (",\n");
+    }
+
     if (content) {
       printf ("\t\"content\": ");
       print_json_string (content);
@@ -402,7 +411,7 @@ list_all_exports (struct nbd_handle *nbd1, const char *uri)
   xmlURIPtr xmluri = NULL;

   for (i = 0; i < nbd_get_nr_list_exports (nbd1); ++i) {
-    char *name, *new_path, *new_uri;
+    char *name, *desc, *new_path, *new_uri;
     struct nbd_handle *nbd2;

     name = nbd_get_list_export_name (nbd1, i);
@@ -437,10 +446,12 @@ list_all_exports (struct nbd_handle *nbd1, const char *uri)
       }

       /* List the metadata of this export. */
-      list_one_export (nbd2);
+      desc = nbd_get_list_export_description (nbd1, i);
+      list_one_export (nbd2, desc);

       nbd_close (nbd2);
       free (new_uri);
+      free (desc);
       xmlFreeURI (xmluri); /* this also frees xmluri->path == new_path */
     }
     free (name);
-- 
2.27.0