From 5c5e51a05b567fd48fb155d94ca6f7679dd0d478 Mon Sep 17 00:00:00 2001 From: Eric Blake Date: Mon, 26 Oct 2015 16:34:50 -0600 Subject: [PATCH] qapi-visit: Remove redundant functions for flat union base The code for visiting the base class of a child struct created visit_type_Base_fields() which covers all fields of Base; while the code for visiting the base class of a flat union created visit_type_Union_fields() covering all fields of the base except the discriminator. But since the base class includes the discriminator of a flat union, we can just visit the entire base, without needing a separate visit of the discriminator. Not only is consistently visiting all fields easier to understand, it lets us share code. The generated code in qapi-visit.c loses several now-unused visit_type_UNION_fields(), along with changes like: |@@ -1654,11 +1557,7 @@ void visit_type_BlockdevOptions(Visitor | if (!*obj) { | goto out_obj; | } |- visit_type_BlockdevOptions_fields(v, obj, &err); |- if (err) { |- goto out_obj; |- } |- visit_type_BlockdevDriver(v, &(*obj)->driver, "driver", &err); |+ visit_type_BlockdevOptionsBase_fields(v, (BlockdevOptionsBase **)obj, &err); | if (err) { | goto out_obj; | } and forward declarations where needed. Note that the cast of obj to BASE ** is necessary to call visit_type_BASE_fields() (and we can't use our upcast wrappers, because those work on pointers while we have a pointer-to-pointer). Signed-off-by: Eric Blake Message-Id: <1445898903-12082-12-git-send-email-eblake@redhat.com> Signed-off-by: Markus Armbruster --- scripts/qapi-visit.py | 32 +++++++++++++++----------------- 1 file changed, 15 insertions(+), 17 deletions(-) diff --git a/scripts/qapi-visit.py b/scripts/qapi-visit.py index f711a720f3..33c013a7fb 100644 --- a/scripts/qapi-visit.py +++ b/scripts/qapi-visit.py @@ -228,8 +228,7 @@ def gen_visit_union(name, base, variants): ret = '' if base: - members = [m for m in base.members if m != variants.tag_member] - ret += gen_visit_struct_fields(name, None, members) + ret += gen_visit_fields_decl(base) for var in variants.variants: # Ugly special case for simple union TODO get rid of it @@ -254,31 +253,30 @@ void visit_type_%(c_name)s(Visitor *v, %(c_name)s **obj, const char *name, Error if base: ret += mcgen(''' - visit_type_%(c_name)s_fields(v, obj, &err); + visit_type_%(c_name)s_fields(v, (%(c_name)s **)obj, &err); ''', - c_name=c_name(name)) - ret += gen_err_check(label='out_obj') - - tag_key = variants.tag_member.name - if not variants.tag_name: - # we pointlessly use a different key for simple unions - tag_key = 'type' - ret += mcgen(''' + c_name=base.c_name()) + else: + ret += mcgen(''' visit_type_%(c_type)s(v, &(*obj)->%(c_name)s, "%(name)s", &err); - if (err) { - goto out_obj; - } +''', + c_type=variants.tag_member.type.c_name(), + # TODO ugly special case for simple union + # Use same tag name in C as on the wire to get rid of + # it, then: c_name=c_name(variants.tag_member.name) + c_name='kind', + name=variants.tag_member.name) + ret += gen_err_check(label='out_obj') + ret += mcgen(''' if (!visit_start_union(v, !!(*obj)->data, &err) || err) { goto out_obj; } switch ((*obj)->%(c_name)s) { ''', - c_type=variants.tag_member.type.c_name(), # TODO ugly special case for simple union # Use same tag name in C as on the wire to get rid of # it, then: c_name=c_name(variants.tag_member.name) - c_name=c_name(variants.tag_name or 'kind'), - name=tag_key) + c_name=c_name(variants.tag_name or 'kind')) for var in variants.variants: # TODO ugly special case for simple union