@@ -43,6 +43,10 @@ typedef enum VisitorType {
struct Visitor
{
+ /*
+ * Only input visitors may fail!
+ */
+
/* Must be set to visit structs */
void (*start_struct)(Visitor *v, const char *name, void **obj,
size_t size, Error **errp);
@@ -82,7 +82,7 @@
* Each function also takes the customary @errp argument (see
* qapi/error.h for details), for reporting any errors (such as if a
* member @name is not present, or is present but not the specified
- * type).
+ * type). Only input visitors can fail.
*
* If an error is detected during visit_type_FOO() with an input
* visitor, then *@obj will be set to NULL for pointer types, and left
@@ -164,19 +164,14 @@
*
* <example>
* Foo *f = ...obtain populated object...
- * Error *err = NULL;
* Visitor *v;
* Type *result;
*
* v = FOO_visitor_new(..., &result);
- * visit_type_Foo(v, NULL, &f, &err);
- * if (err) {
- * ...handle error...
- * } else {
- * visit_complete(v, &result);
- * ...use result...
- * }
+ * visit_type_Foo(v, NULL, &f, &error_abort);
+ * visit_complete(v, &result);
* visit_free(v);
+ * ...use result...
* </example>
*
* It is also possible to use the visitors to do a virtual walk, where
@@ -289,6 +284,7 @@ void visit_free(Visitor *v);
* case @size is ignored.
*
* On failure, set *@obj to NULL and store an error through @errp.
+ * Can happen only when @v is an input visitor.
*
* After visit_start_struct() succeeds, the caller may visit its
* members one after the other, passing the member's name and address
@@ -305,7 +301,8 @@ void visit_start_struct(Visitor *v, const char *name, void **obj,
/*
* Prepare for completing an object visit.
*
- * On failure, store an error through @errp.
+ * On failure, store an error through @errp. Can happen only when @v
+ * is an input visitor.
*
* Should be called prior to visit_end_struct() if all other
* intermediate visit steps were successful, to allow the visitor one
@@ -342,6 +339,7 @@ void visit_end_struct(Visitor *v, void **obj);
* ignored.
*
* On failure, set *@list to NULL and store an error through @errp.
+ * Can happen only when @v is an input visitor.
*
* After visit_start_list() succeeds, the caller may visit its members
* one after the other. A real visit (where @list is non-NULL) uses
@@ -375,7 +373,8 @@ GenericList *visit_next_list(Visitor *v, GenericList *tail, size_t size);
/*
* Prepare for completing a list visit.
*
- * On failure, store an error through @errp.
+ * On failure, store an error through @errp. Can happen only when @v
+ * is an input visitor.
*
* Should be called prior to visit_end_list() if all other
* intermediate visit steps were successful, to allow the visitor one
@@ -411,6 +410,7 @@ void visit_end_list(Visitor *v, void **list);
* (*@obj)->type. Other visitors leave @obj unchanged.
*
* On failure, set *@obj to NULL and store an error through @errp.
+ * Can happen only when @v is an input visitor.
*
* If successful, this must be paired with visit_end_alternate() with
* the same @obj to clean up, even if visiting the contents of the
@@ -465,11 +465,13 @@ bool visit_optional(Visitor *v, const char *name, bool *present);
* visitors produce text output. The mapping between enumeration
* values and strings is done by the visitor core, using @lookup.
*
- * On failure, store an error through @errp.
+ * On failure, store an error through @errp. Can happen only when @v
+ * is an input visitor.
*
* May call visit_type_str() under the hood, and the enum visit may
* fail even if the corresponding string visit succeeded; this implies
- * that visit_type_str() must have no unwelcome side effects.
+ * that an input visitor's visit_type_str() must have no unwelcome
+ * side effects.
*/
void visit_type_enum(Visitor *v, const char *name, int *obj,
const QEnumLookup *lookup, Error **errp);
@@ -495,7 +497,8 @@ bool visit_is_dealloc(Visitor *v);
* @obj must be non-NULL. Input visitors set *@obj to the value;
* other visitors will leave *@obj unchanged.
*
- * On failure, store an error through @errp.
+ * On failure, store an error through @errp. Can happen only when @v
+ * is an input visitor.
*/
void visit_type_int(Visitor *v, const char *name, int64_t *obj, Error **errp);
@@ -573,7 +576,8 @@ void visit_type_size(Visitor *v, const char *name, uint64_t *obj,
* @obj must be non-NULL. Input visitors set *@obj to the value;
* other visitors will leave *@obj unchanged.
*
- * On failure, store an error through @errp.
+ * On failure, store an error through @errp. Can happen only when @v
+ * is an input visitor.
*/
void visit_type_bool(Visitor *v, const char *name, bool *obj, Error **errp);
@@ -592,6 +596,7 @@ void visit_type_bool(Visitor *v, const char *name, bool *obj, Error **errp);
* into @obj for use by an output visitor.
*
* On failure, set *@obj to NULL and store an error through @errp.
+ * Can happen only when @v is an input visitor.
*
* FIXME: Callers that try to output NULL *obj should not be allowed.
*/
@@ -607,7 +612,8 @@ void visit_type_str(Visitor *v, const char *name, char **obj, Error **errp);
* other visitors will leave *@obj unchanged. Visitors should
* document if infinity or NaN are not permitted.
*
- * On failure, store an error through @errp.
+ * On failure, store an error through @errp. Can happen only when @v
+ * is an input visitor.
*/
void visit_type_number(Visitor *v, const char *name, double *obj,
Error **errp);
@@ -623,6 +629,7 @@ void visit_type_number(Visitor *v, const char *name, double *obj,
* for output visitors.
*
* On failure, set *@obj to NULL and store an error through @errp.
+ * Can happen only when @v is an input visitor.
*
* Note that some kinds of input can't express arbitrary QObject.
* E.g. the visitor returned by qobject_input_visitor_new_keyval()
@@ -640,6 +647,7 @@ void visit_type_any(Visitor *v, const char *name, QObject **obj, Error **errp);
* other visitors ignore *@obj.
*
* On failure, set *@obj to NULL and store an error through @errp.
+ * Can happen only when @v is an input visitor.
*/
void visit_type_null(Visitor *v, const char *name, QNull **obj,
Error **errp);
@@ -2982,7 +2982,6 @@ BdrvChild *bdrv_open_child(const char *filename,
BlockDriverState *bdrv_open_blockdev_ref(BlockdevRef *ref, Error **errp)
{
BlockDriverState *bs = NULL;
- Error *local_err = NULL;
QObject *obj = NULL;
QDict *qdict = NULL;
const char *reference = NULL;
@@ -2995,11 +2994,7 @@ BlockDriverState *bdrv_open_blockdev_ref(BlockdevRef *ref, Error **errp)
assert(ref->type == QTYPE_QDICT);
v = qobject_output_visitor_new(&obj);
- visit_type_BlockdevOptions(v, NULL, &options, &local_err);
- if (local_err) {
- error_propagate(errp, local_err);
- goto fail;
- }
+ visit_type_BlockdevOptions(v, NULL, &options, &error_abort);
visit_complete(v, &obj);
qdict = qobject_to(QDict, obj);
@@ -3017,8 +3012,6 @@ BlockDriverState *bdrv_open_blockdev_ref(BlockdevRef *ref, Error **errp)
bs = bdrv_open_inherit(NULL, reference, qdict, 0, NULL, NULL, errp);
obj = NULL;
-
-fail:
qobject_unref(obj);
visit_free(v);
return bs;
@@ -1854,19 +1854,12 @@ static int sd_create_prealloc(BlockdevOptionsSheepdog *location, int64_t size,
Visitor *v;
QObject *obj = NULL;
QDict *qdict;
- Error *local_err = NULL;
int ret;
v = qobject_output_visitor_new(&obj);
- visit_type_BlockdevOptionsSheepdog(v, NULL, &location, &local_err);
+ visit_type_BlockdevOptionsSheepdog(v, NULL, &location, &error_abort);
visit_free(v);
- if (local_err) {
- error_propagate(errp, local_err);
- qobject_unref(obj);
- return -EINVAL;
- }
-
qdict = qobject_to(QDict, obj);
qdict_flatten(qdict);
@@ -3725,14 +3725,8 @@ void qmp_blockdev_add(BlockdevOptions *options, Error **errp)
QObject *obj;
Visitor *v = qobject_output_visitor_new(&obj);
QDict *qdict;
- Error *local_err = NULL;
-
- visit_type_BlockdevOptions(v, NULL, &options, &local_err);
- if (local_err) {
- error_propagate(errp, local_err);
- goto fail;
- }
+ visit_type_BlockdevOptions(v, NULL, &options, &error_abort);
visit_complete(v, &obj);
qdict = qobject_to(QDict, obj);
@@ -3760,7 +3754,6 @@ void qmp_x_blockdev_reopen(BlockdevOptions *options, Error **errp)
AioContext *ctx;
QObject *obj;
Visitor *v = qobject_output_visitor_new(&obj);
- Error *local_err = NULL;
BlockReopenQueue *queue;
QDict *qdict;
@@ -3777,12 +3770,7 @@ void qmp_x_blockdev_reopen(BlockdevOptions *options, Error **errp)
}
/* Put all options in a QDict and flatten it */
- visit_type_BlockdevOptions(v, NULL, &options, &local_err);
- if (local_err) {
- error_propagate(errp, local_err);
- goto fail;
- }
-
+ visit_type_BlockdevOptions(v, NULL, &options, &error_abort);
visit_complete(v, &obj);
qdict = qobject_to(QDict, obj);
@@ -113,7 +113,7 @@ void hmp_info_memdev(Monitor *mon, const QDict *qdict)
while (m) {
v = string_output_visitor_new(false, &str);
- visit_type_uint16List(v, NULL, &m->value->host_nodes, NULL);
+ visit_type_uint16List(v, NULL, &m->value->host_nodes, &error_abort);
monitor_printf(mon, "memory backend: %s\n", m->value->id);
monitor_printf(mon, " size: %" PRId64 "\n", m->value->size);
monitor_printf(mon, " merge: %s\n",
@@ -334,7 +334,8 @@ void hmp_info_migrate(Monitor *mon, const QDict *qdict)
Visitor *v;
char *str;
v = string_output_visitor_new(false, &str);
- visit_type_uint32List(v, NULL, &info->postcopy_vcpu_blocktime, NULL);
+ visit_type_uint32List(v, NULL, &info->postcopy_vcpu_blocktime,
+ &error_abort);
visit_complete(v, &str);
monitor_printf(mon, "postcopy vcpu blocktime: %s\n", str);
g_free(str);