Commit 5cdc8831 authored by Eric Blake's avatar Eric Blake Committed by Markus Armbruster
Browse files

qapi: Simplify visits of optional fields 



None of the visitor callbacks would set an error when testing
if an optional field was present; make this part of the interface
contract by eliminating the errp argument.

The resulting generated code has a nice diff:

|-    visit_optional(v, &has_fdset_id, "fdset-id", &err);
|-    if (err) {
|-        goto out;
|-    }
|+    visit_optional(v, &has_fdset_id, "fdset-id");
|     if (has_fdset_id) {
|         visit_type_int(v, &fdset_id, "fdset-id", &err);
|         if (err) {
|             goto out;
|         }
|     }

Signed-off-by: default avatarEric Blake <eblake@redhat.com>
Message-Id: <1449033659-25497-9-git-send-email-eblake@redhat.com>
Signed-off-by: default avatarMarkus Armbruster <armbru@redhat.com>
parent d00341af

include/qapi/visitor-impl.h

+2 −3
Original line number Diff line number Diff line
@@ -44,9 +44,8 @@ struct Visitor 
    void (*type_any)(Visitor *v, QObject **obj, const char *name,

                     Error **errp);



    /* May be NULL */

    void (*optional)(Visitor *v, bool *present, const char *name,

                     Error **errp);

    /* May be NULL; most useful for input visitors. */

    void (*optional)(Visitor *v, bool *present, const char *name);



    void (*type_uint8)(Visitor *v, uint8_t *obj, const char *name, Error **errp);

    void (*type_uint16)(Visitor *v, uint16_t *obj, const char *name, Error **errp);

include/qapi/visitor.h

+8 −2
Original line number Diff line number Diff line
@@ -36,8 +36,14 @@ void visit_end_implicit_struct(Visitor *v, Error **errp); 
void visit_start_list(Visitor *v, const char *name, Error **errp);

GenericList *visit_next_list(Visitor *v, GenericList **list, Error **errp);

void visit_end_list(Visitor *v, Error **errp);

void visit_optional(Visitor *v, bool *present, const char *name,

                    Error **errp);



/**

 * Check if an optional member @name of an object needs visiting.

 * For input visitors, set *@present according to whether the

 * corresponding visit_type_*() needs calling; for other visitors,

 * leave *@present unchanged.

 */

void visit_optional(Visitor *v, bool *present, const char *name);



/**

 * Determine the qtype of the item @name in the current object visit.

qapi/opts-visitor.c

+1 −1
Original line number Diff line number Diff line
@@ -488,7 +488,7 @@ opts_type_size(Visitor *v, uint64_t *obj, const char *name, Error **errp) 




static void

opts_optional(Visitor *v, bool *present, const char *name, Error **errp)

opts_optional(Visitor *v, bool *present, const char *name)

{

    OptsVisitor *ov = DO_UPCAST(OptsVisitor, visitor, v);

qapi/qapi-visit-core.c

+2 −3
Original line number Diff line number Diff line
@@ -73,11 +73,10 @@ void visit_end_union(Visitor *v, bool data_present, Error **errp) 
    }

}



void visit_optional(Visitor *v, bool *present, const char *name,

                    Error **errp)

void visit_optional(Visitor *v, bool *present, const char *name)

{

    if (v->optional) {

        v->optional(v, present, name, errp);

        v->optional(v, present, name);

    }

}

qapi/qmp-input-visitor.c

+1 −2
Original line number Diff line number Diff line
@@ -303,8 +303,7 @@ static void qmp_input_type_any(Visitor *v, QObject **obj, const char *name, 
    *obj = qobj;

}



static void qmp_input_optional(Visitor *v, bool *present, const char *name,

                               Error **errp)

static void qmp_input_optional(Visitor *v, bool *present, const char *name)

{

    QmpInputVisitor *qiv = to_qiv(v);

    QObject *qobj = qmp_input_get_object(qiv, name, true);