Commit 949ceeb3 authored by Markus Armbruster's avatar Markus Armbruster Committed by Luiz Capitulino
Browse files

qapi: Clean up null checking in generated visitors 



Visitors get passed a pointer to the visited object.  The generated
visitors try to cope with this pointer being null in some places, for
instance like this:

    visit_start_optional(m, obj ? &(*obj)->has_name : NULL, "name", &err);

visit_start_optional() passes its second argument to Visitor method
start_optional.  Three out of three methods dereference it
unconditionally.

I fail to see how this pointer could legitimately be null.

All this useless null checking is highly redundant, which Coverity
duly reports.  About 200 times.

Remove the useless null checks.

Signed-off-by: default avatarMarkus Armbruster <armbru@redhat.com>
Reviewed-by: default avatarEric Blake <eblake@redhat.com>
Signed-off-by: default avatarLuiz Capitulino <lcapitulino@redhat.com>
parent 56bed413

scripts/qapi-visit.py

+7 −7
Original line number Diff line number Diff line
@@ -47,9 +47,9 @@ static void visit_type_%(full_name)s_fields(Visitor *m, %(name)s ** obj, Error * 


    if base:

        ret += mcgen('''

visit_start_implicit_struct(m, obj ? (void**) &(*obj)->%(c_name)s : NULL, sizeof(%(type)s), &err);

visit_start_implicit_struct(m, (void**) &(*obj)->%(c_name)s, sizeof(%(type)s), &err);

if (!err) {

    visit_type_%(type)s_fields(m, obj ? &(*obj)->%(c_prefix)s%(c_name)s : NULL, &err);

    visit_type_%(type)s_fields(m, &(*obj)->%(c_prefix)s%(c_name)s, &err);

    error_propagate(errp, err);

    err = NULL;

    visit_end_implicit_struct(m, &err);
@@ -61,8 +61,8 @@ if (!err) { 
    for argname, argentry, optional, structured in parse_args(members):

        if optional:

            ret += mcgen('''

visit_start_optional(m, obj ? &(*obj)->%(c_prefix)shas_%(c_name)s : NULL, "%(name)s", &err);

if (obj && (*obj)->%(prefix)shas_%(c_name)s) {

visit_start_optional(m, &(*obj)->%(c_prefix)shas_%(c_name)s, "%(name)s", &err);

if ((*obj)->%(prefix)shas_%(c_name)s) {

''',

                         c_prefix=c_var(field_prefix), prefix=field_prefix,

                         c_name=c_var(argname), name=argname)
@@ -72,7 +72,7 @@ if (obj && (*obj)->%(prefix)shas_%(c_name)s) { 
            ret += generate_visit_struct_body(full_name, argname, argentry)

        else:

            ret += mcgen('''

visit_type_%(type)s(m, obj ? &(*obj)->%(c_prefix)s%(c_name)s : NULL, "%(name)s", &err);

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),
@@ -121,7 +121,7 @@ visit_start_struct(m, (void **)obj, "%(name)s", name, sizeof(%(name)s), &err); 


    ret += mcgen('''

if (!err) {

    if (!obj || *obj) {

    if (*obj) {

        visit_type_%(name)s_fields(m, obj, &err);

        error_propagate(errp, err);

        err = NULL;
@@ -273,7 +273,7 @@ void visit_type_%(name)s(Visitor *m, %(name)s ** obj, const char *name, Error ** 
    if (!error_is_set(errp)) {

        visit_start_struct(m, (void **)obj, "%(name)s", name, sizeof(%(name)s), &err);

        if (!err) {

            if (obj && *obj) {

            if (*obj) {

''',

                 name=name)