unicorn/qemu/qapi/qobject-input-visitor.c
Marc-André Lureau 0087625b7e
qobject: Modify qobject_ref() to return obj
For convenience and clarity, make it possible to call qobject_ref() at
the time when the reference is associated with a variable, or
argument, by making qobject_ref() return the same pointer as given.
Use that to simplify the callers.

Backports commit f5a74a5a50387c6f980b2e2f94f062487a1826da from qemu
2018-05-04 10:24:10 -04:00

557 lines
15 KiB
C

/*
* Input Visitor
*
* 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-input-visitor.h"
#include "qapi/visitor-impl.h"
#include "qemu/queue.h"
#include "qemu-common.h"
#include "qapi/qmp/qbool.h"
#include "qapi/qmp/qdict.h"
#include "qapi/qmp/qlist.h"
#include "qapi/qmp/qerror.h"
#include "qapi/qmp/qnull.h"
#include "qapi/qmp/qnum.h"
#include "qapi/qmp/qstring.h"
typedef struct StackObject {
const char *name; /* Name of @obj in its parent, if any */
QObject *obj; /* QDict or QList being visited */
void *qapi; /* sanity check that caller uses same pointer */
GHashTable *h; /* If @obj is QDict: unvisited keys */
const QListEntry *entry; /* If @obj is QList: unvisited tail */
unsigned index; /* If @obj is QList: list index of @entry */
QSLIST_ENTRY(StackObject) node; /* parent */
} StackObject;
struct QObjectInputVisitor {
Visitor visitor;
/* Root of visit at visitor creation. */
QObject *root;
/* Stack of objects being visited (all entries will be either
* QDict or QList). */
QSLIST_HEAD(, StackObject) stack;
GString *errname; /* Accumulator for full_name() */
};
static QObjectInputVisitor *to_qiv(Visitor *v)
{
return container_of(v, QObjectInputVisitor, visitor);
}
/*
* Find the full name of something @qiv is currently visiting.
* @qiv is visiting something named @name in the stack of containers
* @qiv->stack.
* If @n is zero, return its full name.
* If @n is positive, return the full name of the @n-th container
* counting from the top. The stack of containers must have at least
* @n elements.
* The returned string is valid until the next full_name_nth(@v) or
* destruction of @v.
*/
static const char *full_name_nth(QObjectInputVisitor *qiv, const char *name,
int n)
{
StackObject *so;
char buf[32];
if (qiv->errname) {
g_string_truncate(qiv->errname, 0);
} else {
qiv->errname = g_string_new("");
}
QSLIST_FOREACH(so , &qiv->stack, node) {
if (n) {
n--;
} else if (qobject_type(so->obj) == QTYPE_QDICT) {
g_string_prepend(qiv->errname, name ?: "<anonymous>");
g_string_prepend_c(qiv->errname, '.');
} else {
snprintf(buf, sizeof(buf), "[%u]", so->index);
g_string_prepend(qiv->errname, buf);
}
name = so->name;
}
assert(!n);
if (name) {
g_string_prepend(qiv->errname, name);
} else if (qiv->errname->str[0] == '.') {
g_string_erase(qiv->errname, 0, 1);
} else if (!qiv->errname->str[0]) {
return "<anonymous>";
}
return qiv->errname->str;
}
static const char *full_name(QObjectInputVisitor *qiv, const char *name)
{
return full_name_nth(qiv, name, 0);
}
static QObject *qobject_input_try_get_object(QObjectInputVisitor *qiv,
const char *name,
bool consume)
{
StackObject *tos;
QObject *qobj;
QObject *ret;
if (QSLIST_EMPTY(&qiv->stack)) {
/* Starting at root, name is ignored. */
assert(qiv->root);
return qiv->root;
}
/* We are in a container; find the next element. */
tos = QSLIST_FIRST(&qiv->stack);
qobj = tos->obj;
assert(qobj);
if (qobject_type(qobj) == QTYPE_QDICT) {
assert(name);
ret = qdict_get(qobject_to(QDict, qobj), name);
if (tos->h && consume && ret) {
bool removed = g_hash_table_remove(tos->h, name);
assert(removed);
}
} else {
assert(qobject_type(qobj) == QTYPE_QLIST);
assert(!name);
if (tos->entry) {
ret = qlist_entry_obj(tos->entry);
if (consume) {
tos->entry = qlist_next(tos->entry);
}
} else {
ret = NULL;
}
if (consume) {
tos->index++;
}
}
return ret;
}
static QObject *qobject_input_get_object(QObjectInputVisitor *qiv,
const char *name,
bool consume, Error **errp)
{
QObject *obj = qobject_input_try_get_object(qiv, name, consume);
if (!obj) {
error_setg(errp, QERR_MISSING_PARAMETER, full_name(qiv, name));
}
return obj;
}
static void qdict_add_key(const char *key, QObject *obj, void *opaque)
{
GHashTable *h = opaque;
g_hash_table_insert(h, (gpointer) key, NULL);
}
static const QListEntry *qobject_input_push(QObjectInputVisitor *qiv,
const char *name,
QObject *obj, void *qapi)
{
GHashTable *h;
StackObject *tos = g_new0(StackObject, 1);
assert(obj);
tos->name = name;
tos->obj = obj;
tos->qapi = qapi;
if (qobject_type(obj) == QTYPE_QDICT) {
h = g_hash_table_new(g_str_hash, g_str_equal);
qdict_iter(qobject_to(QDict, obj), qdict_add_key, h);
tos->h = h;
} else {
assert(qobject_type(obj) == QTYPE_QLIST);
tos->entry = qlist_first(qobject_to(QList, obj));
tos->index = -1;
}
QSLIST_INSERT_HEAD(&qiv->stack, tos, node);
return tos->entry;
}
static void qobject_input_check_struct(Visitor *v, Error **errp)
{
QObjectInputVisitor *qiv = to_qiv(v);
StackObject *tos = QSLIST_FIRST(&qiv->stack);
GHashTableIter iter;
const char *key;
assert(tos && !tos->entry);
g_hash_table_iter_init(&iter, tos->h);
if (g_hash_table_iter_next(&iter, (void **)&key, NULL)) {
error_setg(errp, "Parameter '%s' is unexpected",
full_name(qiv, key));
}
}
static void qobject_input_stack_object_free(StackObject *tos)
{
if (tos->h) {
g_hash_table_unref(tos->h);
}
g_free(tos);
}
static void qobject_input_pop(Visitor *v, void **obj)
{
QObjectInputVisitor *qiv = to_qiv(v);
StackObject *tos = QSLIST_FIRST(&qiv->stack);
assert(tos && tos->qapi == obj);
QSLIST_REMOVE_HEAD(&qiv->stack, node);
qobject_input_stack_object_free(tos);
}
static void qobject_input_start_struct(Visitor *v, const char *name, void **obj,
size_t size, Error **errp)
{
QObjectInputVisitor *qiv = to_qiv(v);
QObject *qobj = qobject_input_get_object(qiv, name, true, errp);
if (obj) {
*obj = NULL;
}
if (!qobj) {
return;
}
if (qobject_type(qobj) != QTYPE_QDICT) {
error_setg(errp, QERR_INVALID_PARAMETER_TYPE,
full_name(qiv, name), "object");
return;
}
qobject_input_push(qiv, name, qobj, obj);
if (obj) {
*obj = g_malloc0(size);
}
}
static void qobject_input_end_struct(Visitor *v, void **obj)
{
QObjectInputVisitor *qiv = to_qiv(v);
StackObject *tos = QSLIST_FIRST(&qiv->stack);
assert(qobject_type(tos->obj) == QTYPE_QDICT && tos->h);
qobject_input_pop(v, obj);
}
static void qobject_input_start_list(Visitor *v, const char *name,
GenericList **list, size_t size, Error **errp)
{
QObjectInputVisitor *qiv = to_qiv(v);
QObject *qobj = qobject_input_get_object(qiv, name, true, errp);
const QListEntry *entry;
if (list) {
*list = NULL;
}
if (!qobj) {
return;
}
if (qobject_type(qobj) != QTYPE_QLIST) {
error_setg(errp, QERR_INVALID_PARAMETER_TYPE,
full_name(qiv, name), "array");
return;
}
entry = qobject_input_push(qiv, name, qobj, list);
if (entry && list) {
*list = g_malloc0(size);
}
}
static GenericList *qobject_input_next_list(Visitor *v, GenericList *tail,
size_t size)
{
QObjectInputVisitor *qiv = to_qiv(v);
StackObject *tos = QSLIST_FIRST(&qiv->stack);
assert(tos && qobject_to(QList, tos->obj));
if (!tos->entry) {
return NULL;
}
tail->next = g_malloc0(size);
return tail->next;
}
static void qobject_input_check_list(Visitor *v, Error **errp)
{
QObjectInputVisitor *qiv = to_qiv(v);
StackObject *tos = QSLIST_FIRST(&qiv->stack);
assert(tos && qobject_to(QList, tos->obj));
if (tos->entry) {
error_setg(errp, "Only %u list elements expected in %s",
tos->index + 1, full_name_nth(qiv, NULL, 1));
}
}
static void qobject_input_end_list(Visitor *v, void **obj)
{
QObjectInputVisitor *qiv = to_qiv(v);
StackObject *tos = QSLIST_FIRST(&qiv->stack);
assert(qobject_type(tos->obj) == QTYPE_QLIST && !tos->h);
qobject_input_pop(v, obj);
}
static void qobject_input_start_alternate(Visitor *v, const char *name,
GenericAlternate **obj, size_t size,
Error **errp)
{
QObjectInputVisitor *qiv = to_qiv(v);
QObject *qobj = qobject_input_get_object(qiv, name, false, errp);
if (!qobj) {
*obj = NULL;
return;
}
*obj = g_malloc0(size);
(*obj)->type = qobject_type(qobj);
}
static void qobject_input_type_int64(Visitor *v, const char *name, int64_t *obj,
Error **errp)
{
QObjectInputVisitor *qiv = to_qiv(v);
QObject *qobj = qobject_input_get_object(qiv, name, true, errp);
QNum *qnum;
if (!qobj) {
return;
}
qnum = qobject_to(QNum, qobj);
if (!qnum || !qnum_get_try_int(qnum, obj)) {
error_setg(errp, QERR_INVALID_PARAMETER_TYPE,
full_name(qiv, name), "integer");
}
}
static void qobject_input_type_uint64(Visitor *v, const char *name, uint64_t *obj,
Error **errp)
{
QObjectInputVisitor *qiv = to_qiv(v);
QObject *qobj = qobject_input_get_object(qiv, name, true, errp);
QNum *qnum;
int64_t val;
if (!qobj) {
return;
}
qnum = qobject_to(QNum, qobj);
if (!qnum) {
goto err;
}
if (qnum_get_try_uint(qnum, obj)) {
return;
}
/* Need to accept negative values for backward compatibility */
if (qnum_get_try_int(qnum, &val)) {
*obj = val;
return;
}
err:
error_setg(errp, QERR_INVALID_PARAMETER_VALUE,
full_name(qiv, name), "uint64");
}
static void qobject_input_type_bool(Visitor *v, const char *name, bool *obj,
Error **errp)
{
QObjectInputVisitor *qiv = to_qiv(v);
QObject *qobj = qobject_input_get_object(qiv, name, true, errp);
QBool *qbool;
if (!qobj) {
return;
}
qbool = qobject_to(QBool, qobj);
if (!qbool) {
error_setg(errp, QERR_INVALID_PARAMETER_TYPE,
full_name(qiv, name), "boolean");
return;
}
*obj = qbool_get_bool(qbool);
}
static void qobject_input_type_str(Visitor *v, const char *name, char **obj,
Error **errp)
{
QObjectInputVisitor *qiv = to_qiv(v);
QObject *qobj = qobject_input_get_object(qiv, name, true, errp);
QString *qstr;
*obj = NULL;
if (!qobj) {
return;
}
qstr = qobject_to(QString, qobj);
if (!qstr) {
error_setg(errp, QERR_INVALID_PARAMETER_TYPE,
full_name(qiv, name), "string");
return;
}
*obj = g_strdup(qstring_get_str(qstr));
}
static void qobject_input_type_number(Visitor *v, const char *name, double *obj,
Error **errp)
{
QObjectInputVisitor *qiv = to_qiv(v);
QObject *qobj = qobject_input_get_object(qiv, name, true, errp);
QNum *qnum;
if (!qobj) {
return;
}
qnum = qobject_to(QNum, qobj);
if (!qnum) {
error_setg(errp, QERR_INVALID_PARAMETER_TYPE,
full_name(qiv, name), "number");
return;
}
*obj = qnum_get_double(qnum);
}
static void qobject_input_type_any(Visitor *v, const char *name, QObject **obj,
Error **errp)
{
QObjectInputVisitor *qiv = to_qiv(v);
QObject *qobj = qobject_input_get_object(qiv, name, true, errp);
*obj = NULL;
if (!qobj) {
return;
}
*obj = qobject_ref(qobj);
}
static void qobject_input_type_null(Visitor *v, const char *name,
QNull **obj, Error **errp)
{
QObjectInputVisitor *qiv = to_qiv(v);
QObject *qobj = qobject_input_get_object(qiv, name, true, errp);
*obj = NULL;
if (!qobj) {
return;
}
if (qobject_type(qobj) != QTYPE_QNULL) {
error_setg(errp, QERR_INVALID_PARAMETER_TYPE,
full_name(qiv, name), "null");
return;
}
*obj = qnull();
}
static void qobject_input_optional(Visitor *v, const char *name, bool *present)
{
QObjectInputVisitor *qiv = to_qiv(v);
QObject *qobj = qobject_input_try_get_object(qiv, name, false);
if (!qobj) {
*present = false;
return;
}
*present = true;
}
static void qobject_input_free(Visitor *v)
{
QObjectInputVisitor *qiv = to_qiv(v);
while (!QSLIST_EMPTY(&qiv->stack)) {
StackObject *tos = QSLIST_FIRST(&qiv->stack);
QSLIST_REMOVE_HEAD(&qiv->stack, node);
qobject_input_stack_object_free(tos);
}
qobject_unref(qiv->root);
if (qiv->errname) {
g_string_free(qiv->errname, TRUE);
}
g_free(qiv);
}
static QObjectInputVisitor *qobject_input_visitor_base_new(QObject *obj)
{
QObjectInputVisitor *v = g_malloc0(sizeof(*v));
assert(obj);
v->visitor.type = VISITOR_INPUT;
v->visitor.start_struct = qobject_input_start_struct;
v->visitor.check_struct = qobject_input_check_struct;
v->visitor.end_struct = qobject_input_end_struct;
v->visitor.start_alternate = qobject_input_start_alternate;
v->visitor.start_list = qobject_input_start_list;
v->visitor.next_list = qobject_input_next_list;
v->visitor.check_list = qobject_input_check_list;
v->visitor.end_list = qobject_input_end_list;
v->visitor.optional = qobject_input_optional;
v->visitor.free = qobject_input_free;
v->root = qobject_ref(obj);
return v;
}
Visitor *qobject_input_visitor_new(QObject *obj)
{
QObjectInputVisitor *v = qobject_input_visitor_base_new(obj);
v->visitor.type_int64 = qobject_input_type_int64;
v->visitor.type_uint64 = qobject_input_type_uint64;
v->visitor.type_bool = qobject_input_type_bool;
v->visitor.type_str = qobject_input_type_str;
v->visitor.type_number = qobject_input_type_number;
v->visitor.type_any = qobject_input_type_any;
v->visitor.type_null = qobject_input_type_null;
return &v->visitor;
}