Commit ab916fad authored by Eric Blake's avatar Eric Blake Committed by Markus Armbruster
Browse files

qapi: Use 'alternate' to replace anonymous union 



Previous patches have led up to the point where I create the
new meta-type "'alternate':'Foo'".  See the previous patches
for documentation; I intentionally split as much work into
earlier patches to minimize the size of this patch, but a lot
of it is churn due to testsuite fallout after updating to the
new type.

Signed-off-by: default avatarEric Blake <eblake@redhat.com>
Reviewed-by: default avatarMarkus Armbruster <armbru@redhat.com>
Signed-off-by: default avatarMarkus Armbruster <armbru@redhat.com>
parent 7b1b98c4

qapi/block-core.json

+2 −4
Original line number Diff line number Diff line
@@ -1503,8 +1503,7 @@ 
#

# Since: 2.2

##

{ 'union': 'Qcow2OverlapChecks',

  'discriminator': {},

{ 'alternate': 'Qcow2OverlapChecks',

  'data': { 'flags': 'Qcow2OverlapCheckFlags',

            'mode':  'Qcow2OverlapCheckMode' } }
@@ -1795,8 +1794,7 @@ 
#

# Since: 1.7

##

{ 'union': 'BlockdevRef',

  'discriminator': {},

{ 'alternate': 'BlockdevRef',

  'data': { 'definition': 'BlockdevOptions',

            'reference': 'str' } }

scripts/qapi-types.py

+18 −8
Original line number Diff line number Diff line
@@ -172,7 +172,7 @@ typedef enum %(name)s 


def generate_alternate_qtypes(expr):



    name = expr['union']

    name = expr['alternate']

    members = expr['data']



    ret = mcgen('''
@@ -182,7 +182,7 @@ const int %(name)s_qtypes[QTYPE_MAX] = { 


    for key in members:

        qtype = find_alternate_member_qtype(members[key])

        assert qtype, "Invalid anonymous union member"

        assert qtype, "Invalid alternate member"



        ret += mcgen('''

    [ %(qtype)s ] = %(abbrev)s_KIND_%(enum)s,
@@ -197,9 +197,9 @@ const int %(name)s_qtypes[QTYPE_MAX] = { 
    return ret





def generate_union(expr):

def generate_union(expr, meta):



    name = expr['union']

    name = expr[meta]

    typeinfo = expr['data']



    base = expr.get('base')
@@ -243,7 +243,7 @@ struct %(name)s 
    ret += mcgen('''

};

''')

    if discriminator == {}:

    if meta == 'alternate':

        ret += mcgen('''

extern const int %(name)s_qtypes[];

''',
@@ -407,7 +407,11 @@ for expr in exprs: 
            ret += generate_enum('%sKind' % expr['union'], expr['data'].keys())

            fdef.write(generate_enum_lookup('%sKind' % expr['union'],

                                            expr['data'].keys()))

        if expr.get('discriminator') == {}:

    elif expr.has_key('alternate'):

        ret += generate_fwd_struct(expr['alternate'], expr['data']) + "\n"

        ret += generate_enum('%sKind' % expr['alternate'], expr['data'].keys())

        fdef.write(generate_enum_lookup('%sKind' % expr['alternate'],

                                        expr['data'].keys()))

        fdef.write(generate_alternate_qtypes(expr))

    else:

        continue
@@ -438,11 +442,17 @@ for expr in exprs: 
        ret += generate_type_cleanup_decl(expr['type'])

        fdef.write(generate_type_cleanup(expr['type']) + "\n")

    elif expr.has_key('union'):

        ret += generate_union(expr)

        ret += generate_union(expr, 'union')

        ret += generate_type_cleanup_decl(expr['union'] + "List")

        fdef.write(generate_type_cleanup(expr['union'] + "List") + "\n")

        ret += generate_type_cleanup_decl(expr['union'])

        fdef.write(generate_type_cleanup(expr['union']) + "\n")

    elif expr.has_key('alternate'):

        ret += generate_union(expr, 'alternate')

        ret += generate_type_cleanup_decl(expr['alternate'] + "List")

        fdef.write(generate_type_cleanup(expr['alternate'] + "List") + "\n")

        ret += generate_type_cleanup_decl(expr['alternate'])

        fdef.write(generate_type_cleanup(expr['alternate']) + "\n")

    elif expr.has_key('enum'):

        ret += generate_type_cleanup_decl(expr['enum'] + "List")

        fdef.write(generate_type_cleanup(expr['enum'] + "List") + "\n")

scripts/qapi-visit.py

+11 −6
Original line number Diff line number Diff line
@@ -256,7 +256,7 @@ void visit_type_%(name)s(Visitor *m, %(name)s **obj, const char *name, Error **e 
''',

    name=name)



    # For anon union, always use the default enum type automatically generated

    # For alternate, always use the default enum type automatically generated

    # as "'%sKind' % (name)"

    disc_type = '%sKind' % (name)
@@ -264,7 +264,7 @@ void visit_type_%(name)s(Visitor *m, %(name)s **obj, const char *name, Error **e 
        assert (members[key] in builtin_types.keys()

            or find_struct(members[key])

            or find_union(members[key])

            or find_enum(members[key])), "Invalid anonymous union member"

            or find_enum(members[key])), "Invalid alternate member"



        enum_full_value = generate_enum_full_value(disc_type, key)

        ret += mcgen('''
@@ -300,10 +300,6 @@ def generate_visit_union(expr): 
    base = expr.get('base')

    discriminator = expr.get('discriminator')



    if discriminator == {}:

        assert not base

        return generate_visit_alternate(name, members)



    enum_define = discriminator_find_enum_define(expr)

    if enum_define:

        # Use the enum type as discriminator
@@ -568,6 +564,15 @@ for expr in exprs: 
                                     expr['data'].keys())

        ret += generate_declaration(expr['union'], expr['data'])

        fdecl.write(ret)

    elif expr.has_key('alternate'):

        ret = generate_visit_alternate(expr['alternate'], expr['data'])

        ret += generate_visit_list(expr['alternate'], expr['data'])

        fdef.write(ret)



        ret = generate_decl_enum('%sKind' % expr['alternate'],

                                 expr['data'].keys())

        ret += generate_declaration(expr['alternate'], expr['data'])

        fdecl.write(ret)

    elif expr.has_key('enum'):

        ret = generate_visit_list(expr['enum'], expr['data'])

        ret += generate_visit_enum(expr['enum'], expr['data'])

scripts/qapi.py

+14 −18
Original line number Diff line number Diff line
@@ -281,7 +281,6 @@ def check_union(expr, expr_info): 
                                "along with base" %name)



    # Two types of unions, determined by discriminator.

    assert discriminator != {}



    # With no discriminator it is a simple union.

    if discriminator is None:
@@ -344,17 +343,14 @@ def check_union(expr, expr_info): 
            values[c_key] = key



def check_alternate(expr, expr_info):

    name = expr['union']

    base = expr.get('base')

    discriminator = expr.get('discriminator')

    name = expr['alternate']

    members = expr['data']

    values = { 'MAX': '(automatic)' }

    types_seen = {}



    assert discriminator == {}

    if base is not None:

    if expr.get('base') is not None:

        raise QAPIExprError(expr_info,

                            "Anonymous union '%s' must not have a base"

                            "Alternate '%s' must not have a base"

                            % name)



    # Check every branch
@@ -363,23 +359,23 @@ def check_alternate(expr, expr_info): 
        c_key = _generate_enum_string(key)

        if c_key in values:

            raise QAPIExprError(expr_info,

                                "Anonymous union '%s' member '%s' clashes "

                                "with '%s'" % (name, key, values[c_key]))

                                "Alternate '%s' member '%s' clashes with '%s'"

                                % (name, key, values[c_key]))

        values[c_key] = key



        # Ensure alternates have no type conflicts.

        if isinstance(value, list):

            raise QAPIExprError(expr_info,

                                "Anonymous union '%s' member '%s' must "

                                "Alternate '%s' member '%s' must "

                                "not be array type" % (name, key))

        qtype = find_alternate_member_qtype(value)

        if not qtype:

            raise QAPIExprError(expr_info,

                                "Anonymous union '%s' member '%s' has "

                                "Alternate '%s' member '%s' has "

                                "invalid type '%s'" % (name, key, value))

        if qtype in types_seen:

            raise QAPIExprError(expr_info,

                                "Anonymous union '%s' member '%s' can't "

                                "Alternate '%s' member '%s' can't "

                                "be distinguished from member '%s'"

                                % (name, key, types_seen[qtype]))

        types_seen[qtype] = key
@@ -412,10 +408,9 @@ def check_exprs(schema): 
        if expr.has_key('enum'):

            check_enum(expr, info)

        elif expr.has_key('union'):

            if expr.get('discriminator') == {}:

                check_alternate(expr, info)

            else:

            check_union(expr, info)

        elif expr.has_key('alternate'):

            check_alternate(expr, info)

        elif expr.has_key('event'):

            check_event(expr, info)
@@ -447,6 +442,8 @@ def parse_schema(input_file): 
            if expr.has_key('union'):

                if not discriminator_find_enum_define(expr):

                    add_enum('%sKind' % expr['union'])

            elif expr.has_key('alternate'):

                add_enum('%sKind' % expr['alternate'])



        # Final pass - validate that exprs make sense

        check_exprs(schema)
@@ -557,7 +554,6 @@ def find_struct(name): 


def add_union(definition):

    global union_types

    if definition.get('discriminator') != {}:

    union_types.append(definition)



def find_union(name):

tests/qapi-schema/alternate-array.err

+1 −1
Original line number Diff line number Diff line 
tests/qapi-schema/alternate-array.json:5: Anonymous union 'MyUnion' member 'two' must not be array type
 
tests/qapi-schema/alternate-array.json:5: Alternate 'Alt' member 'two' must not be array type