[Qemu-devel] [PATCH v1][ 15/23] qapi: add QAPI dealloc visiter

[Michael Roth <mdroth@linux.vnet.ibm.com>]

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 |  125 +++++++++++++++++++++++++++++++++++++++++++
 qapi/qapi-dealloc-visiter.h |   13 +++++
 2 files changed, 138 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..3c669cc
--- /dev/null
+++ b/qapi/qapi-dealloc-visiter.c
@@ -0,0 +1,125 @@
+#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;
+    assert(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)
+{
+    assert(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..df1fa20
--- /dev/null
+++ b/qapi/qapi-dealloc-visiter.h
@@ -0,0 +1,13 @@
+#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
-- 
1.7.0.4