Eric Blake <ebl...@redhat.com> writes:
> On 03/03/2017 06:32 AM, Markus Armbruster wrote:
>> To enforce capability negotiation before normal operation,
>> handle_qmp_command() inspects every command before it's handed off to
>> qmp_dispatch(). This is a bit of a layering violation, and results in
>> duplicated code.
>>
>> Before capability negotiation (!cur_mon->in_command_mode), we fail
>> commands other than "qmp_capabilities". This is what enforces
>> capability negotiation.
>>
>> Afterwards, we fail command "qmp_capabilities".
>>
>> Clean this up as follows.
>>
>> The obvious place to fail a command is the command itself, so move the
>> "afterwards" check to qmp_qmp_capabilities().
>>
>> We do the "before" check in every other command, but that would be
>> bothersome. Instead, start with an alternate list of commant that
>
> s/commant/commands/
Fixed.
>> contains only "qmp_capabilities". Switch to the full list in
>> qmp_qmp_capabilities().
>>
>> Additionally, replace the generic human-readable error message for
>> CommandNotFound by one that reminds the user to run qmp_capabilities.
>> Without that, we'd regress commit 2d5a834.
>>
>> Signed-off-by: Markus Armbruster <arm...@redhat.com>
>> ---
>> monitor.c | 76
>> +++++++++++++++++++++++++++++++++++----------------------------
>> 1 file changed, 42 insertions(+), 34 deletions(-)
>>
>
>> @@ -3786,11 +3785,20 @@ static void handle_qmp_command(JSONMessageParser
>> *parser, GQueue *tokens)
>> cmd_name = qdict_get_str(qdict, "execute");
>> trace_handle_qmp_command(mon, cmd_name);
>>
>> - if (invalid_qmp_mode(mon, cmd_name, &err)) {
>> - goto err_out;
>> - }
>> + rsp = qmp_dispatch(cur_mon->qmp.commands, req);
>>
>> - rsp = qmp_dispatch(&qmp_commands, req);
>> + qdict = qdict_get_qdict(qobject_to_qdict(rsp), "error");
>> + if (qdict) {
>> + if (mon->qmp.commands == &qmp_cap_negotiation_commands
>> + && !g_strcmp0(qdict_get_try_str(qdict, "class"),
>> + QapiErrorClass_lookup[ERROR_CLASS_COMMAND_NOT_FOUND])) {
>
> Could join these two 'if' into one, for less {}, but that's cosmetic.
Or maybe get reshuffle so that qdict_get_qdict() is called only when
needed:
if (mon->qmp.commands == &qmp_cap_negotiation_commands) {
qdict = qdict_get_qdict(qobject_to_qdict(rsp), "error");
if (qdict
&& !g_strcmp0(qdict_get_try_str(qdict, "class"),
QapiErrorClass_lookup[ERROR_CLASS_COMMAND_NOT_FOUND])) {
/* Provide a more useful error message */
> Reviewed-by: Eric Blake <ebl...@redhat.com>
Thanks!
