On 08/08/2018 07:03 AM, Markus Armbruster wrote:
The last case where qobject_from_json() & friends return null without
setting an error is empty or blank input. Callers:
* block.c's parse_json_protocol() reports "Could not parse the JSON
options". It's marked as a work-around, because it also covered
actual bugs, but they got fixed in the previous few commits.
How would you trigger this? I guess that would be by using the
pseud-json block specification spelled "json:" rather than the usual
"json:{...}".
* qobject_input_visitor_new_str() reports "JSON parse error". Also
marked as work-around. The recent fixes have made this unreachable,
because it currently gets called only for input starting with '{'.
Indeed, no triggers to this.
* check-qjson.c's empty_input() and blank_input() demonstrate the
behavior.
* The other callers are not affected since they only pass input with
exactly one JSON value or, in the case of negative tests, one error.
As long as sending back-to-back newlines to QMP does not treat the empty
line as an error, you should be okay. (If sending two newlines in a row
now results in a {"error":...} response from the server for the blank
line, then you've regressed).
Fail with "Expecting a JSON value" instead of returning null, and
simplify callers.
Signed-off-by: Markus Armbruster <arm...@redhat.com>
---
Yay for getting rid of the inconsistent error reporting!
Reviewed-by: Eric Blake <ebl...@redhat.com>
--
Eric Blake, Principal Software Engineer
Red Hat, Inc. +1-919-301-3266
Virtualization: qemu.org | libvirt.org
