On Thu, Mar 29, 2012 at 01:26:34PM -0500, Anthony Liguori wrote:
> On 03/29/2012 12:26 PM, Luiz Capitulino wrote:
> >This allows for QAPI functions to receive a variable-length argument
> >list. This is going to be used by device_add and netdev_add commands.
> >
> >In the schema, the argument list is represented by type name '**',
> >like this example:
> >
> > { 'command': 'foo', 'data': { 'arg-list': '**' } }
> >
> >Each argument is represented by the KeyValues type and the C
> >implementation should expect a KeyValuesList, like:
> >
> > void qmp_foo(KeyValuesList *values_list, Error **errp);
> >
> >XXX: This implementation is simple but very hacky. We just iterate
> > through all arguments and build the KeyValuesList list to be
> > passed to the QAPI function.
> >
> > Maybe we could have a kwargs type, that does exactly this but
> > through a visitor instead?
> >
> >Signed-off-by: Luiz Capitulino<lcapitul...@redhat.com>
>
> What about just treating '**' as "marshal remaining arguments to a
> string" and then pass that string to device_add? qmp_device_add can
> then parse that string with QemuOpts.
Since currently we explicitly point qmp to the marshaller anyway, we
could also just treat '**' as an indicator to not generate a marshaller.
Then, we open-code the marshaller to process the QDict, rather than embedding
it in the script or passing it through to qmp_device_add().
>From the perspective of qmp_device_add() it then just looks like any
other qmp command.
>
> It's a bit ugly, but that's how things worked. When we introduce
> qom_add, this problem goes away because you would make multiple
> calls to qom_set to set all of the properties.
>
> Regards,
>
> Anthony Liguori
>
> >---
> > qapi-schema.json | 15 +++++++++++++++
> > scripts/qapi-commands.py | 31 ++++++++++++++++++++++++++++---
> > scripts/qapi.py | 2 ++
> > 3 files changed, 45 insertions(+), 3 deletions(-)
> >
> >diff --git a/qapi-schema.json b/qapi-schema.json
> >index 0d11d6e..25bd487 100644
> >--- a/qapi-schema.json
> >+++ b/qapi-schema.json
> >@@ -1701,3 +1701,18 @@
> > # Since: 1.1
> > ##
> > { 'command': 'xen-save-devices-state', 'data': {'filename': 'str'} }
> >+
> >+##
> >+# @KeyValues:
> >+#
> >+# A generic representation of a key value pair.
> >+#
> >+# @key: the name of the item
> >+#
> >+# @value: the string representation of the item value. This typically
> >follows
> >+# QEMU's command line parsing format. See the man pages for more
> >+# information.
> >+#
> >+# Since: 0.14.0
> >+##
> >+{ 'type': 'KeyValues', 'data': {'key': 'str', 'value': 'str'} }
> >diff --git a/scripts/qapi-commands.py b/scripts/qapi-commands.py
> >index 30a24d2..75a6e81 100644
> >--- a/scripts/qapi-commands.py
> >+++ b/scripts/qapi-commands.py
> >@@ -146,19 +146,44 @@ v = qmp_input_get_visitor(mi);
> > obj=obj)
> >
> > for argname, argtype, optional, structured in parse_args(args):
> >- if optional:
> >+ if optional and not '**':
> > ret += mcgen('''
> > visit_start_optional(v,&has_%(c_name)s, "%(name)s", errp);
> > if (has_%(c_name)s) {
> > ''',
> > c_name=c_var(argname), name=argname)
> > push_indent()
> >- ret += mcgen('''
> >+ if argtype == '**':
> >+ if dealloc:
> >+ ret += mcgen('''
> >+qapi_free_KeyValuesList(%(obj)s);
> >+''',
> >+ obj=c_var(argname))
> >+ else:
> >+ ret += mcgen('''
> >+{
> >+ const QDictEntry *entry;
> >+ v = v; /* fix me baby */
> >+
> >+ for (entry = qdict_first(args); entry; entry = qdict_next(qdict,
> >entry)) {
> >+ KeyValuesList *item = g_malloc0(sizeof(*item));
> >+ item->value = g_malloc0(sizeof(*item->value));
> >+ item->value->key = g_strdup(qdict_entry_key(entry));
> >+ item->value->value =
> >g_strdup(qstring_get_str(qobject_to_qstring(qdict_entry_value(entry))));
> >+
> >+ item->next = %(obj)s;
> >+ %(obj)s = item;
> >+ }
> >+}
> >+''',
> >+ obj=c_var(argname))
> >+ else:
> >+ ret += mcgen('''
> > %(visitor)s(v,&%(c_name)s, "%(name)s", errp);
> > ''',
> > c_name=c_var(argname), name=argname, argtype=argtype,
> > visitor=type_visitor(argtype))
> >- if optional:
> >+ if optional and not '**':
> > pop_indent()
> > ret += mcgen('''
> > }
> >diff --git a/scripts/qapi.py b/scripts/qapi.py
> >index e062336..87b9ee6 100644
> >--- a/scripts/qapi.py
> >+++ b/scripts/qapi.py
> >@@ -163,6 +163,8 @@ def c_type(name):
> > return 'bool'
> > elif name == 'number':
> > return 'double'
> >+ elif name == '**':
> >+ return 'KeyValuesList *'
> > elif type(name) == list:
> > return '%s *' % c_list_type(name[0])
> > elif is_enum(name):
>
