[Qemu-devel] [PATCH v6 35/36] qapi: Drop support for inline nested types

[Eric Blake <eblake@redhat.com>]

A future patch will be using a 'name':{dictionary} entry in the
QAPI schema to specify a default value for an optional argument
(see previous commit messages for more details why); but existing
use of inline nested structs conflicts with that goal. Now that
all commands have been changed to avoid inline nested structs,
nuke support for them, and turn it into a hard error. Update the
testsuite to reflect tighter parsing rules.

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>

---

v6: rebase onto earlier changes
---
 scripts/qapi-commands.py                     |  8 +++---
 scripts/qapi-event.py                        |  4 +--
 scripts/qapi-types.py                        |  9 ++-----
 scripts/qapi-visit.py                        | 37 ++++------------------------
 scripts/qapi.py                              | 20 ++++++---------
 tests/qapi-schema/event-nest-struct.err      |  2 +-
 tests/qapi-schema/nested-struct-data.err     |  1 +
 tests/qapi-schema/nested-struct-data.exit    |  2 +-
 tests/qapi-schema/nested-struct-data.json    |  2 +-
 tests/qapi-schema/nested-struct-data.out     |  3 ---
 tests/qapi-schema/nested-struct-returns.err  |  1 +
 tests/qapi-schema/nested-struct-returns.exit |  2 +-
 tests/qapi-schema/nested-struct-returns.json |  2 +-
 tests/qapi-schema/nested-struct-returns.out  |  3 ---
 14 files changed, 27 insertions(+), 69 deletions(-)

diff --git a/scripts/qapi-commands.py b/scripts/qapi-commands.py
index 053ba85..db81044 100644
--- a/scripts/qapi-commands.py
+++ b/scripts/qapi-commands.py
@@ -28,7 +28,7 @@ def type_visitor(name):

 def generate_command_decl(name, args, ret_type):
     arglist=""
-    for argname, argtype, optional, structured in parse_args(args):
+    for argname, argtype, optional in parse_args(args):
         argtype = c_type(argtype, is_param=True)
         if optional:
             arglist += "bool has_%s, " % c_var(argname)
@@ -53,7 +53,7 @@ def gen_sync_call(name, args, ret_type, indent=0):
     retval=""
     if ret_type:
         retval = "retval = "
-    for argname, argtype, optional, structured in parse_args(args):
+    for argname, argtype, optional in parse_args(args):
         if optional:
             arglist += "has_%s, " % c_var(argname)
         arglist += "%s, " % (c_var(argname))
@@ -96,7 +96,7 @@ Visitor *v;
 def gen_visitor_input_vars_decl(args):
     ret = ""
     push_indent()
-    for argname, argtype, optional, structured in parse_args(args):
+    for argname, argtype, optional in parse_args(args):
         if optional:
             ret += mcgen('''
 bool has_%(argname)s = false;
@@ -139,7 +139,7 @@ v = qapi_dealloc_get_visitor(md);
 v = qmp_input_get_visitor(mi);
 ''')

-    for argname, argtype, optional, structured in parse_args(args):
+    for argname, argtype, optional in parse_args(args):
         if optional:
             ret += mcgen('''
 visit_optional(v, &has_%(c_name)s, "%(name)s", %(errp)s);
diff --git a/scripts/qapi-event.py b/scripts/qapi-event.py
index 601e307..47dc041 100644
--- a/scripts/qapi-event.py
+++ b/scripts/qapi-event.py
@@ -21,7 +21,7 @@ def _generate_event_api_name(event_name, params):
     l = len(api_name)

     if params:
-        for argname, argentry, optional, structured in parse_args(params):
+        for argname, argentry, optional in parse_args(params):
             if optional:
                 api_name += "bool has_%s,\n" % c_var(argname)
                 api_name += "".ljust(l)
@@ -93,7 +93,7 @@ def generate_event_implement(api_name, event_name, params):
 """,
                 event_name = event_name)

-        for argname, argentry, optional, structured in parse_args(params):
+        for argname, argentry, optional in parse_args(params):
             if optional:
                 ret += mcgen("""
     if (has_%(var)s) {
diff --git a/scripts/qapi-types.py b/scripts/qapi-types.py
index a429d9e..2bf8145 100644
--- a/scripts/qapi-types.py
+++ b/scripts/qapi-types.py
@@ -63,18 +63,13 @@ typedef struct %(name)sList
 def generate_struct_fields(members):
     ret = ''

-    for argname, argentry, optional, structured in parse_args(members):
+    for argname, argentry, optional in parse_args(members):
         if optional:
             ret += mcgen('''
     bool has_%(c_name)s;
 ''',
                          c_name=c_var(argname))
-        if structured:
-            push_indent()
-            ret += generate_struct({ "field": argname, "data": argentry})
-            pop_indent()
-        else:
-            ret += mcgen('''
+        ret += mcgen('''
     %(c_type)s %(c_name)s;
 ''',
                      c_type=c_type(argentry), c_name=c_var(argname))
diff --git a/scripts/qapi-visit.py b/scripts/qapi-visit.py
index eeeca82..f5d4355 100644
--- a/scripts/qapi-visit.py
+++ b/scripts/qapi-visit.py
@@ -51,27 +51,6 @@ def generate_visit_struct_fields(name, field_prefix, fn_prefix, members, base =
     else:
         full_name = "%s_%s" % (name, fn_prefix)

-    for argname, argentry, optional, structured in parse_args(members):
-        if structured:
-            if not fn_prefix:
-                nested_fn_prefix = argname
-            else:
-                nested_fn_prefix = "%s_%s" % (fn_prefix, argname)
-
-            nested_field_prefix = "%s%s." % (field_prefix, argname)
-            ret += generate_visit_struct_fields(name, nested_field_prefix,
-                                                nested_fn_prefix, argentry)
-            ret += mcgen('''
-
-static void visit_type_%(full_name)s_field_%(c_name)s(Visitor *m, %(name)s **obj, Error **errp)
-{
-''',
-                         name=name, full_name=full_name, c_name=c_var(argname))
-            ret += generate_visit_struct_body(full_name, argname, argentry)
-            ret += mcgen('''
-}
-''')
-
     if base:
         ret += generate_visit_implicit_struct(base)

@@ -94,7 +73,7 @@ if (err) {
                      c_prefix=c_var(field_prefix),
                      type=type_name(base), c_name=c_var('base'))

-    for argname, argentry, optional, structured in parse_args(members):
+    for argname, argentry, optional in parse_args(members):
         if optional:
             ret += mcgen('''
 visit_optional(m, &(*obj)->%(c_prefix)shas_%(c_name)s, "%(name)s", &err);
@@ -104,18 +83,12 @@ if (!err && (*obj)->%(prefix)shas_%(c_name)s) {
                          c_name=c_var(argname), name=argname)
             push_indent()

-        if structured:
-            ret += mcgen('''
-visit_type_%(full_name)s_field_%(c_name)s(m, obj, &err);
-''',
-                         full_name=full_name, c_name=c_var(argname))
-        else:
-            ret += mcgen('''
+        ret += mcgen('''
 visit_type_%(type)s(m, &(*obj)->%(c_prefix)s%(c_name)s, "%(name)s", &err);
 ''',
-                         c_prefix=c_var(field_prefix), prefix=field_prefix,
-                         type=type_name(argentry), c_name=c_var(argname),
-                         name=argname)
+                     c_prefix=c_var(field_prefix), prefix=field_prefix,
+                     type=type_name(argentry), c_name=c_var(argname),
+                     name=argname)

         if optional:
             pop_indent()
diff --git a/scripts/qapi.py b/scripts/qapi.py
index effba38..9fd9b96 100644
--- a/scripts/qapi.py
+++ b/scripts/qapi.py
@@ -373,10 +373,12 @@ def check_type(expr_info, source, value, allow_array = False,
     for (key, arg) in value.items():
         check_name(expr_info, "Member of %s" % source, key,
                    allow_optional=allow_optional)
+        # Todo: allow dictionaries to represent default values of
+        # an optional argument.
         check_type(expr_info, "Member '%s' of %s" % (key, source), arg,
-                   allow_array=True, allow_dict=True, allow_optional=True,
+                   allow_array=True, allow_star=allow_star,
                    allow_metas=['built-in', 'union', 'alternate', 'struct',
-                                'enum'], allow_star=allow_star)
+                                'enum'])

 def check_command(expr, expr_info):
     name = expr['command']
@@ -404,13 +406,6 @@ def check_event(expr, expr_info):
     check_type(expr_info, "'data' for event '%s'" % name,
                expr.get('data'), allow_dict=True, allow_optional=True,
                allow_metas=['union', 'struct'])
-    if params:
-        for argname, argentry, optional, structured in parse_args(params):
-            if structured:
-                raise QAPIExprError(expr_info,
-                                    "Nested structure define in event is not "
-                                    "supported, event '%s', argname '%s'"
-                                    % (expr['event'], argname))

 def check_union(expr, expr_info):
     name = expr['union']
@@ -671,13 +666,12 @@ def parse_args(typeinfo):
         argname = member
         argentry = typeinfo[member]
         optional = False
-        structured = False
         if member.startswith('*'):
             argname = member[1:]
             optional = True
-        if isinstance(argentry, OrderedDict):
-            structured = True
-        yield (argname, argentry, optional, structured)
+        # Todo: allow argentry to be OrderedDict, for providing the
+        # value of an optional argument.
+        yield (argname, argentry, optional)

 def de_camel_case(name):
     new_name = ''
diff --git a/tests/qapi-schema/event-nest-struct.err b/tests/qapi-schema/event-nest-struct.err
index 91bde1c..5a42701 100644
--- a/tests/qapi-schema/event-nest-struct.err
+++ b/tests/qapi-schema/event-nest-struct.err
@@ -1 +1 @@
-tests/qapi-schema/event-nest-struct.json:1: Nested structure define in event is not supported, event 'EVENT_A', argname 'a'
+tests/qapi-schema/event-nest-struct.json:1: Member 'a' of 'data' for event 'EVENT_A' should be a type name
diff --git a/tests/qapi-schema/nested-struct-data.err b/tests/qapi-schema/nested-struct-data.err
index e69de29..da767ba 100644
--- a/tests/qapi-schema/nested-struct-data.err
+++ b/tests/qapi-schema/nested-struct-data.err
@@ -0,0 +1 @@
+tests/qapi-schema/nested-struct-data.json:2: Member 'a' of 'data' for command 'foo' should be a type name
diff --git a/tests/qapi-schema/nested-struct-data.exit b/tests/qapi-schema/nested-struct-data.exit
index 573541a..d00491f 100644
--- a/tests/qapi-schema/nested-struct-data.exit
+++ b/tests/qapi-schema/nested-struct-data.exit
@@ -1 +1 @@
-0
+1
diff --git a/tests/qapi-schema/nested-struct-data.json b/tests/qapi-schema/nested-struct-data.json
index 0247c8c..3d52d2b 100644
--- a/tests/qapi-schema/nested-struct-data.json
+++ b/tests/qapi-schema/nested-struct-data.json
@@ -1,4 +1,4 @@
-# FIXME: inline subtypes collide with our desired future use of defaults
+# inline subtypes collide with our desired future use of defaults
 { 'command': 'foo',
   'data': { 'a' : { 'string' : 'str', 'integer': 'int' }, 'b' : 'str' },
   'returns': {} }
diff --git a/tests/qapi-schema/nested-struct-data.out b/tests/qapi-schema/nested-struct-data.out
index 999cbb8..e69de29 100644
--- a/tests/qapi-schema/nested-struct-data.out
+++ b/tests/qapi-schema/nested-struct-data.out
@@ -1,3 +0,0 @@
-[OrderedDict([('command', 'foo'), ('data', OrderedDict([('a', OrderedDict([('string', 'str'), ('integer', 'int')])), ('b', 'str')])), ('returns', OrderedDict())])]
-[]
-[]
diff --git a/tests/qapi-schema/nested-struct-returns.err b/tests/qapi-schema/nested-struct-returns.err
index e69de29..5238d07 100644
--- a/tests/qapi-schema/nested-struct-returns.err
+++ b/tests/qapi-schema/nested-struct-returns.err
@@ -0,0 +1 @@
+tests/qapi-schema/nested-struct-returns.json:2: Member 'a' of 'returns' for command 'foo' should be a type name
diff --git a/tests/qapi-schema/nested-struct-returns.exit b/tests/qapi-schema/nested-struct-returns.exit
index 573541a..d00491f 100644
--- a/tests/qapi-schema/nested-struct-returns.exit
+++ b/tests/qapi-schema/nested-struct-returns.exit
@@ -1 +1 @@
-0
+1
diff --git a/tests/qapi-schema/nested-struct-returns.json b/tests/qapi-schema/nested-struct-returns.json
index 5a46840..d2cd047 100644
--- a/tests/qapi-schema/nested-struct-returns.json
+++ b/tests/qapi-schema/nested-struct-returns.json
@@ -1,3 +1,3 @@
-# FIXME: inline subtypes collide with our desired future use of defaults
+# inline subtypes collide with our desired future use of defaults
 { 'command': 'foo',
   'returns': { 'a' : { 'string' : 'str', 'integer': 'int' }, 'b' : 'str' } }
diff --git a/tests/qapi-schema/nested-struct-returns.out b/tests/qapi-schema/nested-struct-returns.out
index c53d23b..e69de29 100644
--- a/tests/qapi-schema/nested-struct-returns.out
+++ b/tests/qapi-schema/nested-struct-returns.out
@@ -1,3 +0,0 @@
-[OrderedDict([('command', 'foo'), ('returns', OrderedDict([('a', OrderedDict([('string', 'str'), ('integer', 'int')])), ('b', 'str')]))])]
-[]
-[]
-- 
2.1.0