unicorn/qemu/qapi/qobject-output-visitor.c
Marc-André Lureau fef464c4cb
qapi: update the qobject visitor to use QNUM_U64
Switch to use QNum/uint where appropriate to remove i64 limitation.

The input visitor will cast i64 input to u64 for compatibility
reasons (existing json QMP client already use negative i64 for large
u64, and expect an implicit cast in qemu).

Note: before the patch, uint64_t values above INT64_MAX are sent over
json QMP as negative values, e.g. UINT64_MAX is sent as -1. After the
patch, they are sent unmodified. Clearly a bug fix, but we have to
consider compatibility issues anyway. libvirt should cope fine,
because its parsing of unsigned integers accepts negative values
modulo 2^64. There's hope that other clients will, too.

Backports commit 5923f85fb82df7c8c60a89458a5ae856045e5ab1 from qemu
2018-03-03 18:40:51 -05:00

256 lines
7.5 KiB
C

/*
* 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 "qemu/osdep.h"
#include "qapi/error.h"
#include "qapi/qobject-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;
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 void 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);
}
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 void 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);
}
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 void 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));
}
static void 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));
}
static void 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));
}
static void 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(""));
}
}
static void 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));
}
static void qobject_output_type_any(Visitor *v, const char *name, QObject **obj,
Error **errp)
{
QObjectOutputVisitor *qov = to_qov(v);
qobject_incref(*obj);
qobject_output_add_obj(qov, name, *obj);
}
static void qobject_output_type_null(Visitor *v, const char *name, Error **errp)
{
QObjectOutputVisitor *qov = to_qov(v);
qobject_output_add_obj(qov, name, qnull());
}
/* Finish building, and return the root object.
* The root object is never null. The caller becomes the object's
* owner, and should use qobject_decref() 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 = 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_decref(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;
}