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, 14 insertions, 5 deletions

diff --git a/tests/qemu-iotests/183.out b/tests/qemu-iotests/183.out
index d4be2cb2de..fd9c2e52a5 100644
--- a/tests/qemu-iotests/183.out
+++ b/tests/qemu-iotests/183.out
@@ -11,18 +11,23 @@ Formatting 'TEST_DIR/t.IMGFMT.dest', fmt=IMGFMT size=67108864
 
 === Write something on the source ===
 
-{ 'execute': 'human-monitor-command', 'arguments': { 'command-line': 'qemu-io disk "write -P 0x55 0 64k"' } }
+{ 'execute': 'human-monitor-command',
+       'arguments': { 'command-line':
+                      'qemu-io disk "write -P 0x55 0 64k"' } }
 wrote 65536/65536 bytes at offset 0
 64 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
 {"return": ""}
-{ 'execute': 'human-monitor-command', 'arguments': { 'command-line': 'qemu-io disk "read -P 0x55 0 64k"' } }
+{ 'execute': 'human-monitor-command',
+       'arguments': { 'command-line':
+                      'qemu-io disk "read -P 0x55 0 64k"' } }
 read 65536/65536 bytes at offset 0
 64 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
 {"return": ""}
 
 === Do block migration to destination ===
 
-{ 'execute': 'migrate', 'arguments': { 'uri': 'unix:SOCK_DIR/migrate', 'blk': true } }
+{ 'execute': 'migrate',
+       'arguments': { 'uri': 'unix:SOCK_DIR/migrate', 'blk': true } }
 {"return": {}}
 { 'execute': 'query-status' }
 {"return": {"status": "postmigrate", "singlestep": false, "running": false}}
@@ -32,11 +37,15 @@ read 65536/65536 bytes at offset 0
 { 'execute': 'query-status' }
 {"timestamp": {"seconds":  TIMESTAMP, "microseconds":  TIMESTAMP}, "event": "RESUME"}
 {"return": {"status": "running", "singlestep": false, "running": true}}
-{ 'execute': 'human-monitor-command', 'arguments': { 'command-line': 'qemu-io disk "read -P 0x55 0 64k"' } }
+{ 'execute': 'human-monitor-command',
+       'arguments': { 'command-line':
+                      'qemu-io disk "read -P 0x55 0 64k"' } }
 read 65536/65536 bytes at offset 0
 64 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
 {"return": ""}
-{ 'execute': 'human-monitor-command', 'arguments': { 'command-line': 'qemu-io disk "write -P 0x66 1M 64k"' } }
+{ 'execute': 'human-monitor-command',
+       'arguments': { 'command-line':
+                      'qemu-io disk "write -P 0x66 1M 64k"' } }
 wrote 65536/65536 bytes at offset 1048576
 64 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
 {"return": ""}