diff options
Diffstat (limited to 'qemu/qapi/qapi-dealloc-visitor.c')
| -rw-r--r-- | qemu/qapi/qapi-dealloc-visitor.c | 225 |
1 files changed, 225 insertions, 0 deletions
diff --git a/qemu/qapi/qapi-dealloc-visitor.c b/qemu/qapi/qapi-dealloc-visitor.c new file mode 100644 index 000000000..d7f92c5d6 --- /dev/null +++ b/qemu/qapi/qapi-dealloc-visitor.c @@ -0,0 +1,225 @@ +/* + * Dealloc Visitor + * + * Copyright IBM, Corp. 2011 + * + * Authors: + * Michael Roth <mdroth@linux.vnet.ibm.com> + * + * This work is licensed under the terms of the GNU LGPL, version 2.1 or later. + * See the COPYING.LIB file in the top-level directory. + * + */ + +#include "qapi/dealloc-visitor.h" +#include "qemu/queue.h" +#include "qemu-common.h" +#include "qapi/qmp/types.h" +#include "qapi/visitor-impl.h" + +typedef struct StackEntry +{ + void *value; + bool is_list_head; + QTAILQ_ENTRY(StackEntry) node; +} StackEntry; + +struct QapiDeallocVisitor +{ + Visitor visitor; + QTAILQ_HEAD(, StackEntry) stack; + bool is_list_head; +}; + +static QapiDeallocVisitor *to_qov(Visitor *v) +{ + return container_of(v, QapiDeallocVisitor, visitor); +} + +static void qapi_dealloc_push(QapiDeallocVisitor *qov, void *value) +{ + StackEntry *e = g_malloc0(sizeof(*e)); + + e->value = value; + + /* see if we're just pushing a list head tracker */ + if (value == NULL) { + e->is_list_head = true; + } + QTAILQ_INSERT_HEAD(&qov->stack, e, node); +} + +static void *qapi_dealloc_pop(QapiDeallocVisitor *qov) +{ + StackEntry *e = QTAILQ_FIRST(&qov->stack); + QObject *value; + QTAILQ_REMOVE(&qov->stack, e, node); + value = e->value; + g_free(e); + return value; +} + +static void qapi_dealloc_start_struct(Visitor *v, void **obj, const char *kind, + const char *name, size_t unused, + Error **errp) +{ + QapiDeallocVisitor *qov = to_qov(v); + qapi_dealloc_push(qov, obj); +} + +static void qapi_dealloc_end_struct(Visitor *v, Error **errp) +{ + QapiDeallocVisitor *qov = to_qov(v); + void **obj = qapi_dealloc_pop(qov); + if (obj) { + g_free(*obj); + } +} + +static void qapi_dealloc_start_implicit_struct(Visitor *v, + void **obj, + size_t size, + Error **errp) +{ + QapiDeallocVisitor *qov = to_qov(v); + qapi_dealloc_push(qov, obj); +} + +static void qapi_dealloc_end_implicit_struct(Visitor *v, Error **errp) +{ + QapiDeallocVisitor *qov = to_qov(v); + void **obj = qapi_dealloc_pop(qov); + if (obj) { + g_free(*obj); + } +} + +static void qapi_dealloc_start_list(Visitor *v, const char *name, Error **errp) +{ + QapiDeallocVisitor *qov = to_qov(v); + qapi_dealloc_push(qov, NULL); +} + +static GenericList *qapi_dealloc_next_list(Visitor *v, GenericList **listp, + Error **errp) +{ + GenericList *list = *listp; + QapiDeallocVisitor *qov = to_qov(v); + StackEntry *e = QTAILQ_FIRST(&qov->stack); + + if (e && e->is_list_head) { + e->is_list_head = false; + return list; + } + + if (list) { + list = list->next; + g_free(*listp); + return list; + } + + return NULL; +} + +static void qapi_dealloc_end_list(Visitor *v, Error **errp) +{ + QapiDeallocVisitor *qov = to_qov(v); + void *obj = qapi_dealloc_pop(qov); + assert(obj == NULL); /* should've been list head tracker with no payload */ +} + +static void qapi_dealloc_type_str(Visitor *v, char **obj, const char *name, + Error **errp) +{ + if (obj) { + g_free(*obj); + } +} + +static void qapi_dealloc_type_int(Visitor *v, int64_t *obj, const char *name, + Error **errp) +{ +} + +static void qapi_dealloc_type_bool(Visitor *v, bool *obj, const char *name, + Error **errp) +{ +} + +static void qapi_dealloc_type_number(Visitor *v, double *obj, const char *name, + Error **errp) +{ +} + +static void qapi_dealloc_type_size(Visitor *v, uint64_t *obj, const char *name, + Error **errp) +{ +} + +static void qapi_dealloc_type_enum(Visitor *v, int *obj, + const char * const strings[], + const char *kind, const char *name, + Error **errp) +{ +} + +/* If there's no data present, the dealloc visitor has nothing to free. + * Thus, indicate to visitor code that the subsequent union fields can + * be skipped. This is not an error condition, since the cleanup of the + * rest of an object can continue unhindered, so leave errp unset in + * these cases. + * + * NOTE: In cases where we're attempting to deallocate an object that + * may have missing fields, the field indicating the union type may + * be missing. In such a case, it's possible we don't have enough + * information to differentiate data_present == false from a case where + * data *is* present but happens to be a scalar with a value of 0. + * This is okay, since in the case of the dealloc visitor there's no + * work that needs to done in either situation. + * + * The current inability in QAPI code to more thoroughly verify a union + * type in such cases will likely need to be addressed if we wish to + * implement this interface for other types of visitors in the future, + * however. + */ +static bool qapi_dealloc_start_union(Visitor *v, bool data_present, + Error **errp) +{ + return data_present; +} + +Visitor *qapi_dealloc_get_visitor(QapiDeallocVisitor *v) +{ + return &v->visitor; +} + +void qapi_dealloc_visitor_cleanup(QapiDeallocVisitor *v) +{ + g_free(v); +} + +QapiDeallocVisitor *qapi_dealloc_visitor_new(void) +{ + QapiDeallocVisitor *v; + + v = g_malloc0(sizeof(*v)); + + v->visitor.start_struct = qapi_dealloc_start_struct; + v->visitor.end_struct = qapi_dealloc_end_struct; + v->visitor.start_implicit_struct = qapi_dealloc_start_implicit_struct; + v->visitor.end_implicit_struct = qapi_dealloc_end_implicit_struct; + v->visitor.start_list = qapi_dealloc_start_list; + v->visitor.next_list = qapi_dealloc_next_list; + v->visitor.end_list = qapi_dealloc_end_list; + v->visitor.type_enum = qapi_dealloc_type_enum; + v->visitor.type_int = qapi_dealloc_type_int; + v->visitor.type_bool = qapi_dealloc_type_bool; + v->visitor.type_str = qapi_dealloc_type_str; + v->visitor.type_number = qapi_dealloc_type_number; + v->visitor.type_size = qapi_dealloc_type_size; + v->visitor.start_union = qapi_dealloc_start_union; + + QTAILQ_INIT(&v->stack); + + return v; +} |