qemu-img: Enable progress output for commit

Implement progress output for the commit command by querying the
progress of the block job.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Message-id: 1414159063-25977-11-git-send-email-mreitz@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

qemu-img-cmds.hx

@@ -22,9 +22,9 @@ STEXI
 ETEXI
 
 DEF("commit", img_commit,
-    "commit [-q] [-f fmt] [-t cache] [-d] filename")
+    "commit [-q] [-f fmt] [-t cache] [-d] [-p] filename")
 STEXI
-@item commit [-q] [-f @var{fmt}] [-t @var{cache}] [-d] @var{filename}
+@item commit [-q] [-f @var{fmt}] [-t @var{cache}] [-d] [-p] @var{filename}
 ETEXI
 
 DEF("compare", img_compare,

qemu-img.c

@@ -746,9 +746,14 @@ static void run_block_job(BlockJob *job, Error **errp)
 
     do {
         aio_poll(aio_context, true);
+        qemu_progress_print((float)job->offset / job->len * 100.f, 0);
     } while (!job->ready);
 
     block_job_complete_sync(job, errp);
+
+    /* A block job may finish instantaneously without publishing any progress,
+     * so just signal completion here */
+    qemu_progress_print(100.f, 0);
 }
 
 static int img_commit(int argc, char **argv)
@@ -757,14 +762,14 @@ static int img_commit(int argc, char **argv)
     const char *filename, *fmt, *cache;
     BlockBackend *blk;
     BlockDriverState *bs, *base_bs;
-    bool quiet = false, drop = false;
+    bool progress = false, quiet = false, drop = false;
     Error *local_err = NULL;
     CommonBlockJobCBInfo cbi;
 
     fmt = NULL;
     cache = BDRV_DEFAULT_CACHE;
     for(;;) {
-        c = getopt(argc, argv, "f:ht:dq");
+        c = getopt(argc, argv, "f:ht:dpq");
         if (c == -1) {
             break;
         }
@@ -782,11 +787,20 @@ static int img_commit(int argc, char **argv)
         case 'd':
             drop = true;
             break;
+        case 'p':
+            progress = true;
+            break;
         case 'q':
             quiet = true;
             break;
         }
     }
+
+    /* Progress is not shown in Quiet mode */
+    if (quiet) {
+        progress = false;
+    }
+
     if (optind != argc - 1) {
         error_exit("Expecting one image file name");
     }
@@ -805,6 +819,9 @@ static int img_commit(int argc, char **argv)
     }
     bs = blk_bs(blk);
 
+    qemu_progress_init(progress, 1.f);
+    qemu_progress_print(0.f, 100);
+
     /* This is different from QMP, which by default uses the deepest file in the
      * backing chain (i.e., the very base); however, the traditional behavior of
      * qemu-img commit is using the immediate backing file. */
@@ -853,6 +870,8 @@ unref_backing:
     }
 
 done:
+    qemu_progress_end();
+
     blk_unref(blk);
 
     if (local_err) {

qemu-img.texi

@@ -167,7 +167,7 @@ this case. @var{backing_file} will never be modified unless you use the
 The size can also be specified using the @var{size} option with @code{-o},
 it doesn't need to be specified separately in this case.
 
-@item commit [-f @var{fmt}] [-t @var{cache}] [-d] @var{filename}
+@item commit [-q] [-f @var{fmt}] [-t @var{cache}] [-d] [-p] @var{filename}
 
 Commit the changes recorded in @var{filename} in its base image or backing file.
 If the backing file is smaller than the snapshot, then the backing file will be