Error messages refer to nodes of the QObject being visited by name.
Trouble is the names are sometimes less than helpful:
* The name of the root QObject is whatever @name argument got passed
to the visitor, except NULL gets mapped to "null". We commonly pass
NULL. Not good.
Avoiding errors "at the root" mitigates. For instance,
visit_start_struct() can only fail when the visited object is not a
dictionary, and we commonly ensure it is beforehand.
* The name of a QDict's member is the member key. Good enough only
when this happens to be unique.
* The name of a QList's member is "null". Not good.
Improve error messages by referring to nodes by path instead, as
follows:
* The path of the root QObject is whatever @name argument got passed
to the visitor, except NULL gets mapped to "<anonymous>".
* The path of a root QDict's member is the member key.
* The path of a root QList's member is "[%u]", where %u is the list
index, starting at zero.
* The path of a non-root QDict's member is the path of the QDict
concatenated with "." and the member key.
* The path of a non-root QList's member is the path of the QList
concatenated with "[%u]", where %u is the list index.
For example, the incorrect QMP command
{ "execute": "blockdev-add", "arguments": { "node-name": "foo", "driver": "raw", "file": {"driver": "file" } } }
now fails with
{"error": {"class": "GenericError", "desc": "Parameter 'file.filename' is missing"}}
instead of
{"error": {"class": "GenericError", "desc": "Parameter 'filename' is missing"}}
and
{ "execute": "input-send-event", "arguments": { "device": "bar", "events": [ [] ] } }
now fails with
{"error": {"class": "GenericError", "desc": "Invalid parameter type for 'events[0]', expected: object"}}
instead of
{"error": {"class": "GenericError", "desc": "Invalid parameter type for 'null', expected: QDict"}}
Aside: calling the thing "parameter" is suboptimal for QMP, because
the root object is "arguments" there.
The qobject output visitor doesn't have this problem because it should
not fail. Same for dealloc and clone visitors.
The string visitors don't have this problem because they visit just
one value, whose name needs to be passed to the visitor as @name. The
string output visitor shouldn't fail anyway.
The options visitor uses QemuOpts names. Their name space is flat, so
the use of QDict member keys as names is fine. NULL names used with
roots and lists could conceivably result in bad error messages. Left
for another day.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <1488544368-30622-15-git-send-email-armbru@redhat.com>
qobject_input_start_struct() sets *list, except when it fails because
qobject_input_get_object() fails, i.e. the input object doesn't exist.
All the other input visitor start_struct(), start_list(),
start_alternate() always set *obj / *list.
Change qobject_input_start_struct() to match.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <1488544368-30622-14-git-send-email-armbru@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Drop unused QIV_STACK_SIZE and unused qobject_input_start_struct()
parameter errp.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <1488544368-30622-13-git-send-email-armbru@redhat.com>
The QObject input visitor has three error message formats:
* Parameter '%s' is missing
* "Invalid parameter type for '%s', expected: %s"
* "QMP input object member '%s' is unexpected"
The '%s' are member names (or "null", but I'll fix that later).
The last error message calls the thing "QMP input object member"
instead of "parameter". Misleading when the visitor is used on
QObjects that don't come from QMP. Change it to "Parameter '%s' is
unexpected".
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <1488544368-30622-12-git-send-email-armbru@redhat.com>
The QERR_ macros are leftovers from the days of "rich" error objects.
QERR_QMP_BAD_INPUT_OBJECT, QERR_QMP_BAD_INPUT_OBJECT_MEMBER,
QERR_QMP_EXTRA_MEMBER are used in just one place now, except for one
use that has crept into qobject-input-visitor.c.
Drop these macros, to make the (bad) error messages more visible.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <1488544368-30622-10-git-send-email-armbru@redhat.com>
The QmpInputVisitor has no direct dependency on QMP. It is
valid to use it anywhere that one has a QObject. Rename it
to better reflect its functionality as a generic QObject
to QAPI converter.
The previous commit renamed the files, this one renames C identifiers.
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1475246744-29302-5-git-send-email-berrange@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
[Straightforwardly rebased, split into file and identifier rename]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
The QMP visitors have no direct dependency on QMP. It is
valid to use them anywhere that one has a QObject. Rename them
to better reflect their functionality as a generic QObject
to QAPI converter.
This is the first of three parts: rename the files. The next two
parts will rename C identifiers. The split is necessary to make git
rename detection work.
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
[Split into file and identifier rename, two comments touched up]
Signed-off-by: Markus Armbruster <armbru@redhat.com>