qemu/qapi/qobject-output-visitor.c

267 lines
7.8 KiB
C

/*
* Core Definitions for QAPI/QMP Command Registry
*
* Copyright (C) 2012-2016 Red Hat, Inc.
* 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 "qemu/osdep.h"
#include "qapi/qobject-output-visitor.h"
#include "qapi/visitor-impl.h"
#include "qemu/queue.h"
#include "qapi/qmp/qbool.h"
#include "qapi/qmp/qdict.h"
#include "qapi/qmp/qlist.h"
#include "qapi/qmp/qnull.h"
#include "qapi/qmp/qnum.h"
#include "qapi/qmp/qstring.h"
typedef struct QStackEntry {
QObject *value;
void *qapi; /* sanity check that caller uses same pointer */
QSLIST_ENTRY(QStackEntry) node;
} QStackEntry;
struct QObjectOutputVisitor {
Visitor visitor;
QSLIST_HEAD(, QStackEntry) stack; /* Stack of unfinished containers */
QObject *root; /* Root of the output visit */
QObject **result; /* User's storage location for result */
};
#define qobject_output_add(qov, name, value) \
qobject_output_add_obj(qov, name, QOBJECT(value))
#define qobject_output_push(qov, value, qapi) \
qobject_output_push_obj(qov, QOBJECT(value), qapi)
static QObjectOutputVisitor *to_qov(Visitor *v)
{
return container_of(v, QObjectOutputVisitor, visitor);
}
/* Push @value onto the stack of current QObjects being built */
static void qobject_output_push_obj(QObjectOutputVisitor *qov, QObject *value,
void *qapi)
{
QStackEntry *e = g_malloc0(sizeof(*e));
assert(qov->root);
assert(value);
e->value = value;
e->qapi = qapi;
QSLIST_INSERT_HEAD(&qov->stack, e, node);
}
/* Pop a value off the stack of QObjects being built, and return it. */
static QObject *qobject_output_pop(QObjectOutputVisitor *qov, void *qapi)
{
QStackEntry *e = QSLIST_FIRST(&qov->stack);
QObject *value;
assert(e);
assert(e->qapi == qapi);
QSLIST_REMOVE_HEAD(&qov->stack, node);
value = e->value;
assert(value);
g_free(e);
return value;
}
/* Add @value to the current QObject being built.
* If the stack is visiting a dictionary or list, @value is now owned
* by that container. Otherwise, @value is now the root. */
static void qobject_output_add_obj(QObjectOutputVisitor *qov, const char *name,
QObject *value)
{
QStackEntry *e = QSLIST_FIRST(&qov->stack);
QObject *cur = e ? e->value : NULL;
if (!cur) {
/* Don't allow reuse of visitor on more than one root */
assert(!qov->root);
qov->root = value;
} else {
switch (qobject_type(cur)) {
case QTYPE_QDICT:
assert(name);
qdict_put_obj(qobject_to(QDict, cur), name, value);
break;
case QTYPE_QLIST:
assert(!name);
qlist_append_obj(qobject_to(QList, cur), value);
break;
default:
g_assert_not_reached();
}
}
}
static bool qobject_output_start_struct(Visitor *v, const char *name,
void **obj, size_t unused, Error **errp)
{
QObjectOutputVisitor *qov = to_qov(v);
QDict *dict = qdict_new();
qobject_output_add(qov, name, dict);
qobject_output_push(qov, dict, obj);
return true;
}
static void qobject_output_end_struct(Visitor *v, void **obj)
{
QObjectOutputVisitor *qov = to_qov(v);
QObject *value = qobject_output_pop(qov, obj);
assert(qobject_type(value) == QTYPE_QDICT);
}
static bool qobject_output_start_list(Visitor *v, const char *name,
GenericList **listp, size_t size,
Error **errp)
{
QObjectOutputVisitor *qov = to_qov(v);
QList *list = qlist_new();
qobject_output_add(qov, name, list);
qobject_output_push(qov, list, listp);
return true;
}
static GenericList *qobject_output_next_list(Visitor *v, GenericList *tail,
size_t size)
{
return tail->next;
}
static void qobject_output_end_list(Visitor *v, void **obj)
{
QObjectOutputVisitor *qov = to_qov(v);
QObject *value = qobject_output_pop(qov, obj);
assert(qobject_type(value) == QTYPE_QLIST);
}
static bool qobject_output_type_int64(Visitor *v, const char *name,
int64_t *obj, Error **errp)
{
QObjectOutputVisitor *qov = to_qov(v);
qobject_output_add(qov, name, qnum_from_int(*obj));
return true;
}
static bool qobject_output_type_uint64(Visitor *v, const char *name,
uint64_t *obj, Error **errp)
{
QObjectOutputVisitor *qov = to_qov(v);
qobject_output_add(qov, name, qnum_from_uint(*obj));
return true;
}
static bool qobject_output_type_bool(Visitor *v, const char *name, bool *obj,
Error **errp)
{
QObjectOutputVisitor *qov = to_qov(v);
qobject_output_add(qov, name, qbool_from_bool(*obj));
return true;
}
static bool qobject_output_type_str(Visitor *v, const char *name, char **obj,
Error **errp)
{
QObjectOutputVisitor *qov = to_qov(v);
if (*obj) {
qobject_output_add(qov, name, qstring_from_str(*obj));
} else {
qobject_output_add(qov, name, qstring_from_str(""));
}
return true;
}
static bool qobject_output_type_number(Visitor *v, const char *name,
double *obj, Error **errp)
{
QObjectOutputVisitor *qov = to_qov(v);
qobject_output_add(qov, name, qnum_from_double(*obj));
return true;
}
static bool qobject_output_type_any(Visitor *v, const char *name,
QObject **obj, Error **errp)
{
QObjectOutputVisitor *qov = to_qov(v);
qobject_output_add_obj(qov, name, qobject_ref(*obj));
return true;
}
static bool qobject_output_type_null(Visitor *v, const char *name,
QNull **obj, Error **errp)
{
QObjectOutputVisitor *qov = to_qov(v);
qobject_output_add(qov, name, qnull());
return true;
}
/* Finish building, and return the root object.
* The root object is never null. The caller becomes the object's
* owner, and should use qobject_unref() when done with it. */
static void qobject_output_complete(Visitor *v, void *opaque)
{
QObjectOutputVisitor *qov = to_qov(v);
/* A visit must have occurred, with each start paired with end. */
assert(qov->root && QSLIST_EMPTY(&qov->stack));
assert(opaque == qov->result);
*qov->result = qobject_ref(qov->root);
qov->result = NULL;
}
static void qobject_output_free(Visitor *v)
{
QObjectOutputVisitor *qov = to_qov(v);
QStackEntry *e;
while (!QSLIST_EMPTY(&qov->stack)) {
e = QSLIST_FIRST(&qov->stack);
QSLIST_REMOVE_HEAD(&qov->stack, node);
g_free(e);
}
qobject_unref(qov->root);
g_free(qov);
}
Visitor *qobject_output_visitor_new(QObject **result)
{
QObjectOutputVisitor *v;
v = g_malloc0(sizeof(*v));
v->visitor.type = VISITOR_OUTPUT;
v->visitor.start_struct = qobject_output_start_struct;
v->visitor.end_struct = qobject_output_end_struct;
v->visitor.start_list = qobject_output_start_list;
v->visitor.next_list = qobject_output_next_list;
v->visitor.end_list = qobject_output_end_list;
v->visitor.type_int64 = qobject_output_type_int64;
v->visitor.type_uint64 = qobject_output_type_uint64;
v->visitor.type_bool = qobject_output_type_bool;
v->visitor.type_str = qobject_output_type_str;
v->visitor.type_number = qobject_output_type_number;
v->visitor.type_any = qobject_output_type_any;
v->visitor.type_null = qobject_output_type_null;
v->visitor.complete = qobject_output_complete;
v->visitor.free = qobject_output_free;
*result = NULL;
v->result = result;
return &v->visitor;
}