Re: [Qemu-devel] [PATCH v2][ 12/21] qapi: add QAPI dealloc visiter

[Anthony Liguori <anthony@codemonkey.ws>]

On 06/03/2011 05:33 PM, Michael Roth wrote:
> Type of Visiter class that can be passed into a qapi-generated C
> type's visiter function to free() any heap-allocated data types.
>
> Signed-off-by: Michael Roth<mdroth@linux.vnet.ibm.com>
> ---
>   qapi/qapi-dealloc-visiter.c |  127 +++++++++++++++++++++++++++++++++++++++++++
>   qapi/qapi-dealloc-visiter.h |   26 +++++++++
>   2 files changed, 153 insertions(+), 0 deletions(-)
>   create mode 100644 qapi/qapi-dealloc-visiter.c
>   create mode 100644 qapi/qapi-dealloc-visiter.h
>
> diff --git a/qapi/qapi-dealloc-visiter.c b/qapi/qapi-dealloc-visiter.c
> new file mode 100644
> index 0000000..fe5e68d

This turned out really nice.

Regards,

Anthony Liguori

> --- /dev/null
> +++ b/qapi/qapi-dealloc-visiter.c
> @@ -0,0 +1,127 @@
> +#include "qapi-dealloc-visiter.h"
> +#include "qemu-queue.h"
> +#include "qemu-common.h"
> +#include "qemu-objects.h"
> +
> +typedef struct StackEntry
> +{
> +    void *value;
> +    QTAILQ_ENTRY(StackEntry) node;
> +} StackEntry;
> +
> +struct QapiDeallocVisiter
> +{
> +    Visiter visiter;
> +    QTAILQ_HEAD(, StackEntry) stack;
> +};
> +
> +static QapiDeallocVisiter *to_qov(Visiter *v)
> +{
> +    return container_of(v, QapiDeallocVisiter, visiter);
> +}
> +
> +static void qapi_dealloc_push(QapiDeallocVisiter *qov, void *value)
> +{
> +    StackEntry *e = qemu_mallocz(sizeof(*e));
> +
> +    e->value = value;
> +    QTAILQ_INSERT_HEAD(&qov->stack, e, node);
> +}
> +
> +static void *qapi_dealloc_pop(QapiDeallocVisiter *qov)
> +{
> +    StackEntry *e = QTAILQ_FIRST(&qov->stack);
> +    QObject *value;
> +    QTAILQ_REMOVE(&qov->stack, e, node);
> +    value = e->value;
> +    qemu_free(e);
> +    return value;
> +}
> +
> +static void qapi_dealloc_start_struct(Visiter *v, void **obj, const char *kind, const char *name, Error **errp)
> +{
> +    QapiDeallocVisiter *qov = to_qov(v);
> +    qapi_dealloc_push(qov, obj);
> +}
> +
> +static void qapi_dealloc_end_struct(Visiter *v, Error **errp)
> +{
> +    QapiDeallocVisiter *qov = to_qov(v);
> +    void **obj = qapi_dealloc_pop(qov);
> +    if (obj&&  *obj) {
> +        qemu_free(*obj);
> +    }
> +}
> +
> +static void qapi_dealloc_start_list(Visiter *v, const char *name, Error **errp)
> +{
> +}
> +
> +static GenericList *qapi_dealloc_next_list(Visiter *v, GenericList **list, Error **errp)
> +{
> +    GenericList *retval = *list;
> +    if (retval->value) {
> +        qemu_free(retval->value);
> +    }
> +    *list = retval->next;
> +    return retval;
> +}
> +
> +static void qapi_dealloc_end_list(Visiter *v, Error **errp)
> +{
> +}
> +
> +static void qapi_dealloc_type_str(Visiter *v, char **obj, const char *name, Error **errp)
> +{
> +    if (obj&&  *obj) {
> +        qemu_free(*obj);
> +    }
> +}
> +
> +static void qapi_dealloc_type_int(Visiter *v, int64_t *obj, const char *name, Error **errp)
> +{
> +}
> +
> +static void qapi_dealloc_type_bool(Visiter *v, bool *obj, const char *name, Error **errp)
> +{
> +}
> +
> +static void qapi_dealloc_type_number(Visiter *v, double *obj, const char *name, Error **errp)
> +{
> +}
> +
> +static void qapi_dealloc_type_enum(Visiter *v, int *obj, const char *kind, const char *name, Error **errp)
> +{
> +}
> +
> +Visiter *qapi_dealloc_get_visiter(QapiDeallocVisiter *v)
> +{
> +    return&v->visiter;
> +}
> +
> +void qapi_dealloc_visiter_cleanup(QapiDeallocVisiter *v)
> +{
> +    qemu_free(v);
> +}
> +
> +QapiDeallocVisiter *qapi_dealloc_visiter_new(void)
> +{
> +    QapiDeallocVisiter *v;
> +
> +    v = qemu_mallocz(sizeof(*v));
> +
> +    v->visiter.start_struct = qapi_dealloc_start_struct;
> +    v->visiter.end_struct = qapi_dealloc_end_struct;
> +    v->visiter.start_list = qapi_dealloc_start_list;
> +    v->visiter.next_list = qapi_dealloc_next_list;
> +    v->visiter.end_list = qapi_dealloc_end_list;
> +    v->visiter.type_enum = qapi_dealloc_type_enum;
> +    v->visiter.type_int = qapi_dealloc_type_int;
> +    v->visiter.type_bool = qapi_dealloc_type_bool;
> +    v->visiter.type_str = qapi_dealloc_type_str;
> +    v->visiter.type_number = qapi_dealloc_type_number;
> +
> +    QTAILQ_INIT(&v->stack);
> +
> +    return v;
> +}
> diff --git a/qapi/qapi-dealloc-visiter.h b/qapi/qapi-dealloc-visiter.h
> new file mode 100644
> index 0000000..9192fc8
> --- /dev/null
> +++ b/qapi/qapi-dealloc-visiter.h
> @@ -0,0 +1,26 @@
> +/*
> + * Dealloc Visiter
> + *
> + * 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.
> + *
> + */
> +
> +#ifndef QAPI_DEALLOC_VISITER_H
> +#define QAPI_DEALLOC_VISITER_H
> +
> +#include "qapi-visit-core.h"
> +
> +typedef struct QapiDeallocVisiter QapiDeallocVisiter;
> +
> +QapiDeallocVisiter *qapi_dealloc_visiter_new(void);
> +void qapi_dealloc_visiter_cleanup(QapiDeallocVisiter *d);
> +
> +Visiter *qapi_dealloc_get_visiter(QapiDeallocVisiter *v);
> +
> +#endif