iotests: Fix _send_qemu_cmd with bash 5.1

With bash 5.1, the output of the following script changes:

  a=("double  space")
  a=${a[@]:0:1}
  echo "$a"

from "double space" to "double  space", i.e. all white space is
preserved as-is.  This is probably what we actually want here (judging
from the "...to accommodate pathnames with spaces" comment), but before
5.1, we would have to quote the ${} slice to get the same behavior.

In any case, without quoting, the reference output of many iotests is
different between bash 5.1 and pre-5.1, which is not very good.  The
output of 5.1 is what we want, so whatever we do to get pre-5.1 to the
same result, it means we have to fix the reference output of basically
all tests that invoke _send_qemu_cmd (except the ones that only use
single spaces in the commands they invoke).

Instead of quoting the ${} slice (cmd="${$@: 1:...}"), we can also just
not use array slicing and replace the whole thing with a simple "cmd=$1;
shift", which works because all callers quote the whole $cmd argument
anyway.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-Id: <20201217153803.101231-3-mreitz@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>

1 files changed, 34 insertions, 8 deletions

diff --git a/tests/qemu-iotests/182.out b/tests/qemu-iotests/182.out
index ce23340..57f7265 100644
--- a/tests/qemu-iotests/182.out
+++ b/tests/qemu-iotests/182.out
@@ -10,16 +10,42 @@ Is another process using the image [TEST_DIR/t.qcow2]?
 
 {'execute': 'qmp_capabilities'}
 {"return": {}}
-{'execute': 'blockdev-add', 'arguments': { 'node-name': 'node0', 'driver': 'file', 'filename': 'TEST_DIR/t.IMGFMT', 'locking': 'on' } }
-{"return": {}}
-{'execute': 'blockdev-snapshot-sync', 'arguments': { 'node-name': 'node0', 'snapshot-file': 'TEST_DIR/t.IMGFMT.overlay', 'snapshot-node-name': 'node1' } }
+{'execute': 'blockdev-add',
+      'arguments': {
+          'node-name': 'node0',
+          'driver': 'file',
+          'filename': 'TEST_DIR/t.IMGFMT',
+          'locking': 'on'
+          } }
+{"return": {}}
+{'execute': 'blockdev-snapshot-sync',
+      'arguments': {
+          'node-name': 'node0',
+          'snapshot-file': 'TEST_DIR/t.IMGFMT.overlay',
+          'snapshot-node-name': 'node1'
+      } }
 Formatting 'TEST_DIR/t.qcow2.overlay', fmt=qcow2 cluster_size=65536 extended_l2=off compression_type=zlib size=197120 backing_file=TEST_DIR/t.qcow2 backing_fmt=file lazy_refcounts=off refcount_bits=16
 {"return": {}}
-{'execute': 'blockdev-add', 'arguments': { 'node-name': 'node1', 'driver': 'file', 'filename': 'TEST_DIR/t.IMGFMT', 'locking': 'on' } }
-{"return": {}}
-{'execute': 'nbd-server-start', 'arguments': { 'addr': { 'type': 'unix', 'data': { 'path': 'SOCK_DIR/nbd.socket' } } } }
-{"return": {}}
-{'execute': 'nbd-server-add', 'arguments': { 'device': 'node1' } }
+{'execute': 'blockdev-add',
+      'arguments': {
+          'node-name': 'node1',
+          'driver': 'file',
+          'filename': 'TEST_DIR/t.IMGFMT',
+          'locking': 'on'
+          } }
+{"return": {}}
+{'execute': 'nbd-server-start',
+      'arguments': {
+          'addr': {
+              'type': 'unix',
+              'data': {
+                  'path': 'SOCK_DIR/nbd.socket'
+              } } } }
+{"return": {}}
+{'execute': 'nbd-server-add',
+      'arguments': {
+          'device': 'node1'
+      } }
 {"return": {}}
 
 === Testing failure to loosen restrictions ===