import

qemu/qapi/qmp-output-visitor.c

@@ -0,0 +1,241 @@
+/*
+ * Core Definitions for QAPI/QMP Command Registry
+ *
+ * Copyright IBM, Corp. 2011
+ *
+ * Authors:
+ *  Anthony Liguori   <aliguori@us.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/qmp-output-visitor.h"
+#include "qapi/visitor-impl.h"
+#include "qemu/queue.h"
+#include "qemu-common.h"
+#include "qapi/qmp/types.h"
+#include "qapi/qmp/qerror.h"
+
+typedef struct QStackEntry
+{
+    QObject *value;
+    bool is_list_head;
+    QTAILQ_ENTRY(QStackEntry) node;
+} QStackEntry;
+
+typedef QTAILQ_HEAD(QStack, QStackEntry) QStack;
+
+struct QmpOutputVisitor
+{
+    Visitor visitor;
+    QStack stack;
+};
+
+#define qmp_output_add(qov, name, value) \
+    qmp_output_add_obj(qov, name, QOBJECT(value))
+#define qmp_output_push(qov, value) qmp_output_push_obj(qov, QOBJECT(value))
+
+static QmpOutputVisitor *to_qov(Visitor *v)
+{
+    return container_of(v, QmpOutputVisitor, visitor);
+}
+
+static void qmp_output_push_obj(QmpOutputVisitor *qov, QObject *value)
+{
+    QStackEntry *e = g_malloc0(sizeof(*e));
+
+    e->value = value;
+    if (qobject_type(e->value) == QTYPE_QLIST) {
+        e->is_list_head = true;
+    }
+    QTAILQ_INSERT_HEAD(&qov->stack, e, node);
+}
+
+static QObject *qmp_output_pop(QmpOutputVisitor *qov)
+{
+    QStackEntry *e = QTAILQ_FIRST(&qov->stack);
+    QObject *value;
+    QTAILQ_REMOVE(&qov->stack, e, node);
+    value = e->value;
+    g_free(e);
+    return value;
+}
+
+static QObject *qmp_output_first(QmpOutputVisitor *qov)
+{
+    QStackEntry *e = QTAILQ_LAST(&qov->stack, QStack);
+
+    /* FIXME - find a better way to deal with NULL values */
+    if (!e) {
+        return NULL;
+    }
+
+    return e->value;
+}
+
+static QObject *qmp_output_last(QmpOutputVisitor *qov)
+{
+    QStackEntry *e = QTAILQ_FIRST(&qov->stack);
+    return e->value;
+}
+
+static void qmp_output_add_obj(QmpOutputVisitor *qov, const char *name,
+                               QObject *value)
+{
+    QObject *cur;
+
+    if (QTAILQ_EMPTY(&qov->stack)) {
+        qmp_output_push_obj(qov, value);
+        return;
+    }
+
+    cur = qmp_output_last(qov);
+
+    switch (qobject_type(cur)) {
+    case QTYPE_QDICT:
+        qdict_put_obj(qobject_to_qdict(cur), name, value);
+        break;
+    case QTYPE_QLIST:
+        qlist_append_obj(qobject_to_qlist(cur), value);
+        break;
+    default:
+        qobject_decref(qmp_output_pop(qov));
+        qmp_output_push_obj(qov, value);
+        break;
+    }
+}
+
+static void qmp_output_start_struct(Visitor *v, void **obj, const char *kind,
+                                    const char *name, size_t unused,
+                                    Error **errp)
+{
+    QmpOutputVisitor *qov = to_qov(v);
+    QDict *dict = qdict_new();
+
+    qmp_output_add(qov, name, dict);
+    qmp_output_push(qov, dict);
+}
+
+static void qmp_output_end_struct(Visitor *v, Error **errp)
+{
+    QmpOutputVisitor *qov = to_qov(v);
+    qmp_output_pop(qov);
+}
+
+static void qmp_output_start_list(Visitor *v, const char *name, Error **errp)
+{
+    QmpOutputVisitor *qov = to_qov(v);
+    QList *list = qlist_new();
+
+    qmp_output_add(qov, name, list);
+    qmp_output_push(qov, list);
+}
+
+static GenericList *qmp_output_next_list(Visitor *v, GenericList **listp,
+                                         Error **errp)
+{
+    GenericList *list = *listp;
+    QmpOutputVisitor *qov = to_qov(v);
+    QStackEntry *e = QTAILQ_FIRST(&qov->stack);
+
+    assert(e);
+    if (e->is_list_head) {
+        e->is_list_head = false;
+        return list;
+    }
+
+    return list ? list->next : NULL;
+}
+
+static void qmp_output_end_list(Visitor *v, Error **errp)
+{
+    QmpOutputVisitor *qov = to_qov(v);
+    qmp_output_pop(qov);
+}
+
+static void qmp_output_type_int(Visitor *v, int64_t *obj, const char *name,
+                                Error **errp)
+{
+    QmpOutputVisitor *qov = to_qov(v);
+    qmp_output_add(qov, name, qint_from_int(*obj));
+}
+
+static void qmp_output_type_bool(Visitor *v, bool *obj, const char *name,
+                                 Error **errp)
+{
+    QmpOutputVisitor *qov = to_qov(v);
+    qmp_output_add(qov, name, qbool_from_int(*obj));
+}
+
+static void qmp_output_type_str(Visitor *v, char **obj, const char *name,
+                                Error **errp)
+{
+    QmpOutputVisitor *qov = to_qov(v);
+    if (*obj) {
+        qmp_output_add(qov, name, qstring_from_str(*obj));
+    } else {
+        qmp_output_add(qov, name, qstring_from_str(""));
+    }
+}
+
+static void qmp_output_type_number(Visitor *v, double *obj, const char *name,
+                                   Error **errp)
+{
+    QmpOutputVisitor *qov = to_qov(v);
+    qmp_output_add(qov, name, qfloat_from_double(*obj));
+}
+
+QObject *qmp_output_get_qobject(QmpOutputVisitor *qov)
+{
+    QObject *obj = qmp_output_first(qov);
+    if (obj) {
+        qobject_incref(obj);
+    }
+    return obj;
+}
+
+Visitor *qmp_output_get_visitor(QmpOutputVisitor *v)
+{
+    return &v->visitor;
+}
+
+void qmp_output_visitor_cleanup(QmpOutputVisitor *v)
+{
+    QStackEntry *e, *tmp;
+
+    /* The bottom QStackEntry, if any, owns the root QObject. See the
+     * qmp_output_push_obj() invocations in qmp_output_add_obj(). */
+    QObject *root = QTAILQ_EMPTY(&v->stack) ? NULL : qmp_output_first(v);
+
+    QTAILQ_FOREACH_SAFE(e, &v->stack, node, tmp) {
+        QTAILQ_REMOVE(&v->stack, e, node);
+        g_free(e);
+    }
+
+    qobject_decref(root);
+    g_free(v);
+}
+
+QmpOutputVisitor *qmp_output_visitor_new(void)
+{
+    QmpOutputVisitor *v;
+
+    v = g_malloc0(sizeof(*v));
+
+    v->visitor.start_struct = qmp_output_start_struct;
+    v->visitor.end_struct = qmp_output_end_struct;
+    v->visitor.start_list = qmp_output_start_list;
+    v->visitor.next_list = qmp_output_next_list;
+    v->visitor.end_list = qmp_output_end_list;
+    v->visitor.type_enum = output_type_enum;
+    v->visitor.type_int = qmp_output_type_int;
+    v->visitor.type_bool = qmp_output_type_bool;
+    v->visitor.type_str = qmp_output_type_str;
+    v->visitor.type_number = qmp_output_type_number;
+
+    QTAILQ_INIT(&v->stack);
+
+    return v;
+}