Am 20.06.2022 um 18:26 hat Hanna Reitz geschrieben:
When a block driver supports obtaining format-specific information, but
that object only contains optional fields, it is possible that none of
them are present, so that dump_qobject() (called by
bdrv_image_info_specific_dump()) will not print anything.
The callers of bdrv_image_info_specific_dump() put a header above this
information ("Format specific information:\n"), which will look strange
when there is nothing below. Modify bdrv_image_info_specific_dump() to
print this header instead of its callers, and only if there is indeed
something to be printed.
Signed-off-by: Hanna Reitz <hreitz@redhat.com>
diff --git a/qemu-io-cmds.c b/qemu-io-cmds.c
index 2f0d8ac25a..084ec44d3b 100644
--- a/qemu-io-cmds.c
+++ b/qemu-io-cmds.c
@@ -1819,8 +1819,8 @@ static int info_f(BlockBackend *blk, int argc, char
**argv)
return -EIO;
}
if (spec_info) {
- printf("Format specific information:\n");
- bdrv_image_info_specific_dump(spec_info);
+ bdrv_image_info_specific_dump(spec_info,
+ "Format specific information:\n");
qapi_free_ImageInfoSpecific(spec_info);
}
Interesting observation here: That qemu-io uses printf() instead of
qemu_printf() for the top level, but then dump_qobject() (which results
in qemu_printf()) for the format specific information, means that if you
use the 'qemu-io' HMP command, you'll get half of the output on stdout
and the other half in the monitor.