From bceae7697ff1711675c26f715b945737bc6849ae Mon Sep 17 00:00:00 2001 From: Wenchao Xia Date: Thu, 6 Mar 2014 17:08:56 -0800 Subject: qapi script: support enum type as discriminator in union By default, any union will automatically generate a enum type as "[UnionName]Kind" in C code, and it is duplicated when the discriminator is specified as a pre-defined enum type in schema. After this patch, the pre-defined enum type will be really used as the switch case condition in generated C code, if discriminator is an enum field. Signed-off-by: Wenchao Xia Reviewed-by: Markus Armbruster Signed-off-by: Luiz Capitulino --- scripts/qapi-types.py | 18 ++++++++++++++---- scripts/qapi-visit.py | 29 ++++++++++++++++++++--------- scripts/qapi.py | 27 ++++++++++++++++++++++++++- 3 files changed, 60 insertions(+), 14 deletions(-) (limited to 'scripts') diff --git a/scripts/qapi-types.py b/scripts/qapi-types.py index 5885bac5ba..10864efc58 100644 --- a/scripts/qapi-types.py +++ b/scripts/qapi-types.py @@ -201,14 +201,21 @@ def generate_union(expr): base = expr.get('base') discriminator = expr.get('discriminator') + enum_define = discriminator_find_enum_define(expr) + if enum_define: + discriminator_type_name = enum_define['enum_name'] + else: + discriminator_type_name = '%sKind' % (name) + ret = mcgen(''' struct %(name)s { - %(name)sKind kind; + %(discriminator_type_name)s kind; union { void *data; ''', - name=name) + name=name, + discriminator_type_name=discriminator_type_name) for key in typeinfo: ret += mcgen(''' @@ -389,8 +396,11 @@ for expr in exprs: fdef.write(generate_enum_lookup(expr['enum'], expr['data'])) elif expr.has_key('union'): ret += generate_fwd_struct(expr['union'], expr['data']) + "\n" - ret += generate_enum('%sKind' % expr['union'], expr['data'].keys()) - fdef.write(generate_enum_lookup('%sKind' % expr['union'], expr['data'].keys())) + enum_define = discriminator_find_enum_define(expr) + if not enum_define: + ret += generate_enum('%sKind' % expr['union'], expr['data'].keys()) + fdef.write(generate_enum_lookup('%sKind' % expr['union'], + expr['data'].keys())) if expr.get('discriminator') == {}: fdef.write(generate_anon_union_qtypes(expr)) else: diff --git a/scripts/qapi-visit.py b/scripts/qapi-visit.py index 0baaf606dc..45ce3a957a 100644 --- a/scripts/qapi-visit.py +++ b/scripts/qapi-visit.py @@ -259,10 +259,16 @@ def generate_visit_union(expr): assert not base return generate_visit_anon_union(name, members) - # There will always be a discriminator in the C switch code, by default it - # is an enum type generated silently as "'%sKind' % (name)" - ret = generate_visit_enum('%sKind' % name, members.keys()) - disc_type = '%sKind' % (name) + enum_define = discriminator_find_enum_define(expr) + if enum_define: + # Use the enum type as discriminator + ret = "" + disc_type = enum_define['enum_name'] + else: + # There will always be a discriminator in the C switch code, by default it + # is an enum type generated silently as "'%sKind' % (name)" + ret = generate_visit_enum('%sKind' % name, members.keys()) + disc_type = '%sKind' % (name) if base: base_fields = find_struct(base)['data'] @@ -298,15 +304,16 @@ void visit_type_%(name)s(Visitor *m, %(name)s ** obj, const char *name, Error ** pop_indent() if not discriminator: - desc_type = "type" + disc_key = "type" else: - desc_type = discriminator + disc_key = discriminator ret += mcgen(''' - visit_type_%(name)sKind(m, &(*obj)->kind, "%(type)s", &err); + visit_type_%(disc_type)s(m, &(*obj)->kind, "%(disc_key)s", &err); if (!err) { switch ((*obj)->kind) { ''', - name=name, type=desc_type) + disc_type = disc_type, + disc_key = disc_key) for key in members: if not discriminator: @@ -517,7 +524,11 @@ for expr in exprs: ret += generate_visit_list(expr['union'], expr['data']) fdef.write(ret) - ret = generate_decl_enum('%sKind' % expr['union'], expr['data'].keys()) + enum_define = discriminator_find_enum_define(expr) + ret = "" + if not enum_define: + ret = generate_decl_enum('%sKind' % expr['union'], + expr['data'].keys()) ret += generate_declaration(expr['union'], expr['data']) fdecl.write(ret) elif expr.has_key('enum'): diff --git a/scripts/qapi.py b/scripts/qapi.py index eebc8a7061..2b43ad2f1b 100644 --- a/scripts/qapi.py +++ b/scripts/qapi.py @@ -180,6 +180,25 @@ def find_base_fields(base): return None return base_struct_define['data'] +# Return the discriminator enum define if discriminator is specified as an +# enum type, otherwise return None. +def discriminator_find_enum_define(expr): + base = expr.get('base') + discriminator = expr.get('discriminator') + + if not (discriminator and base): + return None + + base_fields = find_base_fields(base) + if not base_fields: + return None + + discriminator_type = base_fields.get(discriminator) + if not discriminator_type: + return None + + return find_enum(discriminator_type) + def check_union(expr, expr_info): name = expr['union'] base = expr.get('base') @@ -254,11 +273,17 @@ def parse_schema(fp): add_enum(expr['enum'], expr['data']) elif expr.has_key('union'): add_union(expr) - add_enum('%sKind' % expr['union']) elif expr.has_key('type'): add_struct(expr) exprs.append(expr) + # Try again for hidden UnionKind enum + for expr_elem in schema.exprs: + expr = expr_elem['expr'] + if expr.has_key('union'): + if not discriminator_find_enum_define(expr): + add_enum('%sKind' % expr['union']) + try: check_exprs(schema) except QAPIExprError, e: -- cgit v1.2.1