[Qemu-devel] [PULL 06/23] qapi: Use strict QMP input visitor in more places

[Markus Armbruster <armbru@redhat.com>]

From: Eric Blake <eblake@redhat.com>

The following uses of a QMP input visitor should be strict
(that is, excess keys in QDict input should be flagged if not
converted to QAPI):

- Testsuite code unrelated to explicitly testing non-strict
mode (test-qmp-commands, test-visitor-serialization); since
we want more code to be strict by default, having more tests
of strict mode doesn't hurt

- Code used for cloning QAPI objects (replay-input.c,
qemu-sockets.c); we are reparsing a QObject just barely
produced by the qmp output visitor and which therefore should
not have any garbage, so while it is extra work to be strict,
it validates that our clone is correct [note that a later patch
series will simplify these two uses by creating an actual
clone visitor that is much more efficient than a
generate/reparse cycle]

- qmp_object_add(), which calls into user_creatable_add_type().
Since command line parsing for '-object' uses the same
user_creatable_add_type() through the OptsVisitor, and that is
always strict, we want to ensure that any nested dictionaries
would be treated the same in QMP and from the command line (I
don't actually know if such nested dictionaries exist).  Note
that on this code change, strictness only matters for nested
dictionaries (if even possible), since we already flag excess
input at the top level during an earlier object_property_set()
on an unknown key, whether from QemuOpts:

$ ./x86_64-softmmu/qemu-system-x86_64 -nographic -nodefaults -qmp stdio -object secret,id=sec0,data=letmein,format=raw,foo=bar
qemu-system-x86_64: -object secret,id=sec0,data=letmein,format=raw,foo=bar: Property '.foo' not found

or from QMP:

$ ./x86_64-softmmu/qemu-system-x86_64 -nographic -nodefaults -qmp stdio
{"QMP": {"version": {"qemu": {"micro": 93, "minor": 5, "major": 2}, "package": ""}, "capabilities": []}}
{"execute":"qmp_capabilities"}
{"return": {}}
{"execute":"object-add","arguments":{"qom-type":"secret","id":"sec0","props":{"format":"raw","data":"letmein","foo":"bar"}}}
{"error": {"class": "GenericError", "desc": "Property '.foo' not found"}}

The only remaining uses of non-strict input visits are:

- QMP 'qom-set' (which eventually executes
object_property_set_qobject()) - mark it as something to revisit
in the future (I didn't want to spend any more time on this patch
auditing if we have any QOM dictionary properties that might be
impacted, and couldn't easily prove whether this code path is
shared with anything else).

- test-qmp-input-visitor: explicit tests of non-strict mode. If
we later get rid of users that don't need strictness, then this
test should be merged with test-qmp-input-strict

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1461879932-9020-7-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
---
 qmp.c                              | 2 +-
 qom/qom-qobject.c                  | 1 +
 replay/replay-input.c              | 2 +-
 tests/test-qmp-commands.c          | 2 +-
 tests/test-visitor-serialization.c | 2 +-
 util/qemu-sockets.c                | 2 +-
 6 files changed, 6 insertions(+), 5 deletions(-)

diff --git a/qmp.c b/qmp.c
index 0cc9f3a..e784a67 100644
--- a/qmp.c
+++ b/qmp.c
@@ -663,7 +663,7 @@ void qmp_object_add(const char *type, const char *id,
         }
     }
 
-    qiv = qmp_input_visitor_new(props, false);
+    qiv = qmp_input_visitor_new(props, true);
     obj = user_creatable_add_type(type, id, pdict,
                                   qmp_input_get_visitor(qiv), errp);
     qmp_input_visitor_cleanup(qiv);
diff --git a/qom/qom-qobject.c b/qom/qom-qobject.c
index 451fed6..b66088d 100644
--- a/qom/qom-qobject.c
+++ b/qom/qom-qobject.c
@@ -22,6 +22,7 @@ void object_property_set_qobject(Object *obj, QObject *value,
                                  const char *name, Error **errp)
 {
     QmpInputVisitor *qiv;
+    /* TODO: Should we reject, rather than ignore, excess input? */
     qiv = qmp_input_visitor_new(value, false);
     object_property_set(obj, qmp_input_get_visitor(qiv), name, errp);
 
diff --git a/replay/replay-input.c b/replay/replay-input.c
index 8e8536a..03e99d5 100644
--- a/replay/replay-input.c
+++ b/replay/replay-input.c
@@ -37,7 +37,7 @@ static InputEvent *qapi_clone_InputEvent(InputEvent *src)
         return NULL;
     }
 
-    qiv = qmp_input_visitor_new(obj, false);
+    qiv = qmp_input_visitor_new(obj, true);
     iv = qmp_input_get_visitor(qiv);
     visit_type_InputEvent(iv, NULL, &dst, &error_abort);
     qmp_input_visitor_cleanup(qiv);
diff --git a/tests/test-qmp-commands.c b/tests/test-qmp-commands.c
index a8d37c4..597fb44 100644
--- a/tests/test-qmp-commands.c
+++ b/tests/test-qmp-commands.c
@@ -222,7 +222,7 @@ static void test_dealloc_partial(void)
         ud2_dict = qdict_new();
         qdict_put_obj(ud2_dict, "string0", QOBJECT(qstring_from_str(text)));
 
-        qiv = qmp_input_visitor_new(QOBJECT(ud2_dict), false);
+        qiv = qmp_input_visitor_new(QOBJECT(ud2_dict), true);
         visit_type_UserDefTwo(qmp_input_get_visitor(qiv), NULL, &ud2, &err);
         qmp_input_visitor_cleanup(qiv);
         QDECREF(ud2_dict);
diff --git a/tests/test-visitor-serialization.c b/tests/test-visitor-serialization.c
index 2caac2b..7b14b5a 100644
--- a/tests/test-visitor-serialization.c
+++ b/tests/test-visitor-serialization.c
@@ -1038,7 +1038,7 @@ static void qmp_deserialize(void **native_out, void *datap,
     obj = qobject_from_json(qstring_get_str(output_json));
 
     QDECREF(output_json);
-    d->qiv = qmp_input_visitor_new(obj, false);
+    d->qiv = qmp_input_visitor_new(obj, true);
     qobject_decref(obj_orig);
     qobject_decref(obj);
     visit(qmp_input_get_visitor(d->qiv), native_out, errp);
diff --git a/util/qemu-sockets.c b/util/qemu-sockets.c
index aab5344..2a2c524 100644
--- a/util/qemu-sockets.c
+++ b/util/qemu-sockets.c
@@ -1145,7 +1145,7 @@ void qapi_copy_SocketAddress(SocketAddress **p_dest,
         return;
     }
 
-    qiv = qmp_input_visitor_new(obj, false);
+    qiv = qmp_input_visitor_new(obj, true);
     iv = qmp_input_get_visitor(qiv);
     visit_type_SocketAddress(iv, NULL, p_dest, &error_abort);
     qmp_input_visitor_cleanup(qiv);
-- 
2.5.5