qapi/qmp-input-visitor.c - qemu - Git at Google

 /*
  * Input Visitor
  *
  * 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/error.h"
 #include "qapi/qmp-input-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"

 #define QIV_STACK_SIZE 1024

 typedef struct StackObject
 {
     QObject *obj; /* Object being visited */
     void *qapi; /* sanity check that caller uses same pointer */

     GHashTable *h;           /* If obj is dict: unvisited keys */
     const QListEntry *entry; /* If obj is list: unvisited tail */
 } StackObject;

 struct QmpInputVisitor
 {
     Visitor visitor;

     /* Root of visit at visitor creation. */
     QObject *root;

     /* Stack of objects being visited (all entries will be either
      * QDict or QList). */
     StackObject stack[QIV_STACK_SIZE];
     int nb_stack;

     /* True to reject parse in visit_end_struct() if unvisited keys remain. */
     bool strict;
 };

 static QmpInputVisitor *to_qiv(Visitor *v)
 {
     return container_of(v, QmpInputVisitor, visitor);
 }

 static QObject *qmp_input_get_object(QmpInputVisitor *qiv,
                                      const char *name,
                                      bool consume)
 {
     StackObject *tos;
     QObject *qobj;
     QObject *ret;

     if (!qiv->nb_stack) {
         /* Starting at root, name is ignored. */
         return qiv->root;
     }

     /* We are in a container; find the next element. */
     tos = &qiv->stack[qiv->nb_stack - 1];
     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);
         ret = qlist_entry_obj(tos->entry);
         if (consume) {
             tos->entry = qlist_next(tos->entry);
         }
     }

     return ret;
 }

 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 *qmp_input_push(QmpInputVisitor *qiv, QObject *obj,
                                         void *qapi, Error **errp)
 {
     GHashTable *h;
     StackObject *tos = &qiv->stack[qiv->nb_stack];

     assert(obj);
     if (qiv->nb_stack >= QIV_STACK_SIZE) {
         error_setg(errp, "An internal buffer overran");
         return NULL;
     }

     tos->obj = obj;
     tos->qapi = qapi;
     assert(!tos->h);
     assert(!tos->entry);

     if (qiv->strict && 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 if (qobject_type(obj) == QTYPE_QLIST) {
         tos->entry = qlist_first(qobject_to_qlist(obj));
     }

     qiv->nb_stack++;
     return tos->entry;
 }


 static void qmp_input_check_struct(Visitor *v, Error **errp)
 {
     QmpInputVisitor *qiv = to_qiv(v);
     StackObject *tos = &qiv->stack[qiv->nb_stack - 1];

     assert(qiv->nb_stack > 0);

     if (qiv->strict) {
         GHashTable *const top_ht = tos->h;
         if (top_ht) {
             GHashTableIter iter;
             const char *key;

             g_hash_table_iter_init(&iter, top_ht);
             if (g_hash_table_iter_next(&iter, (void **)&key, NULL)) {
                 error_setg(errp, QERR_QMP_EXTRA_MEMBER, key);
             }
         }
     }
 }

 static void qmp_input_pop(Visitor *v, void **obj)
 {
     QmpInputVisitor *qiv = to_qiv(v);
     StackObject *tos = &qiv->stack[qiv->nb_stack - 1];

     assert(qiv->nb_stack > 0);
     assert(tos->qapi == obj);

     if (qiv->strict) {
         GHashTable * const top_ht = qiv->stack[qiv->nb_stack - 1].h;
         if (top_ht) {
             g_hash_table_unref(top_ht);
         }
         tos->h = NULL;
     }

     qiv->nb_stack--;
 }

 static void qmp_input_start_struct(Visitor *v, const char *name, void **obj,
                                    size_t size, Error **errp)
 {
     QmpInputVisitor *qiv = to_qiv(v);
     QObject *qobj = qmp_input_get_object(qiv, name, true);
     Error *err = NULL;

     if (obj) {
         *obj = NULL;
     }
     if (!qobj || qobject_type(qobj) != QTYPE_QDICT) {
         error_setg(errp, QERR_INVALID_PARAMETER_TYPE, name ? name : "null",
                    "QDict");
         return;
     }

     qmp_input_push(qiv, qobj, obj, &err);
     if (err) {
         error_propagate(errp, err);
         return;
     }

     if (obj) {
         *obj = g_malloc0(size);
     }
 }


 static void qmp_input_start_list(Visitor *v, const char *name,
                                  GenericList **list, size_t size, Error **errp)
 {
     QmpInputVisitor *qiv = to_qiv(v);
     QObject *qobj = qmp_input_get_object(qiv, name, true);
     const QListEntry *entry;

     if (!qobj || qobject_type(qobj) != QTYPE_QLIST) {
         if (list) {
             *list = NULL;
         }
         error_setg(errp, QERR_INVALID_PARAMETER_TYPE, name ? name : "null",
                    "list");
         return;
     }

     entry = qmp_input_push(qiv, qobj, list, errp);
     if (list) {
         if (entry) {
             *list = g_malloc0(size);
         } else {
             *list = NULL;
         }
     }
 }

 static GenericList *qmp_input_next_list(Visitor *v, GenericList *tail,
                                         size_t size)
 {
     QmpInputVisitor *qiv = to_qiv(v);
     StackObject *so = &qiv->stack[qiv->nb_stack - 1];

     if (!so->entry) {
         return NULL;
     }
     tail->next = g_malloc0(size);
     return tail->next;
 }


 static void qmp_input_start_alternate(Visitor *v, const char *name,
                                       GenericAlternate **obj, size_t size,
                                       bool promote_int, Error **errp)
 {
     QmpInputVisitor *qiv = to_qiv(v);
     QObject *qobj = qmp_input_get_object(qiv, name, false);

     if (!qobj) {
         *obj = NULL;
         error_setg(errp, QERR_MISSING_PARAMETER, name ? name : "null");
         return;
     }
     *obj = g_malloc0(size);
     (*obj)->type = qobject_type(qobj);
     if (promote_int && (*obj)->type == QTYPE_QINT) {
         (*obj)->type = QTYPE_QFLOAT;
     }
 }

 static void qmp_input_type_int64(Visitor *v, const char *name, int64_t *obj,
                                  Error **errp)
 {
     QmpInputVisitor *qiv = to_qiv(v);
     QInt *qint = qobject_to_qint(qmp_input_get_object(qiv, name, true));

     if (!qint) {
         error_setg(errp, QERR_INVALID_PARAMETER_TYPE, name ? name : "null",
                    "integer");
         return;
     }

     *obj = qint_get_int(qint);
 }

 static void qmp_input_type_uint64(Visitor *v, const char *name, uint64_t *obj,
                                   Error **errp)
 {
     /* FIXME: qobject_to_qint mishandles values over INT64_MAX */
     QmpInputVisitor *qiv = to_qiv(v);
     QInt *qint = qobject_to_qint(qmp_input_get_object(qiv, name, true));

     if (!qint) {
         error_setg(errp, QERR_INVALID_PARAMETER_TYPE, name ? name : "null",
                    "integer");
         return;
     }

     *obj = qint_get_int(qint);
 }

 static void qmp_input_type_bool(Visitor *v, const char *name, bool *obj,
                                 Error **errp)
 {
     QmpInputVisitor *qiv = to_qiv(v);
     QBool *qbool = qobject_to_qbool(qmp_input_get_object(qiv, name, true));

     if (!qbool) {
         error_setg(errp, QERR_INVALID_PARAMETER_TYPE, name ? name : "null",
                    "boolean");
         return;
     }

     *obj = qbool_get_bool(qbool);
 }

 static void qmp_input_type_str(Visitor *v, const char *name, char **obj,
                                Error **errp)
 {
     QmpInputVisitor *qiv = to_qiv(v);
     QString *qstr = qobject_to_qstring(qmp_input_get_object(qiv, name, true));

     if (!qstr) {
         *obj = NULL;
         error_setg(errp, QERR_INVALID_PARAMETER_TYPE, name ? name : "null",
                    "string");
         return;
     }

     *obj = g_strdup(qstring_get_str(qstr));
 }

 static void qmp_input_type_number(Visitor *v, const char *name, double *obj,
                                   Error **errp)
 {
     QmpInputVisitor *qiv = to_qiv(v);
     QObject *qobj = qmp_input_get_object(qiv, name, true);
     QInt *qint;
     QFloat *qfloat;

     qint = qobject_to_qint(qobj);
     if (qint) {
         *obj = qint_get_int(qobject_to_qint(qobj));
         return;
     }

     qfloat = qobject_to_qfloat(qobj);
     if (qfloat) {
         *obj = qfloat_get_double(qobject_to_qfloat(qobj));
         return;
     }

     error_setg(errp, QERR_INVALID_PARAMETER_TYPE, name ? name : "null",
                "number");
 }

 static void qmp_input_type_any(Visitor *v, const char *name, QObject **obj,
                                Error **errp)
 {
     QmpInputVisitor *qiv = to_qiv(v);
     QObject *qobj = qmp_input_get_object(qiv, name, true);

     qobject_incref(qobj);
     *obj = qobj;
 }

 static void qmp_input_type_null(Visitor *v, const char *name, Error **errp)
 {
     QmpInputVisitor *qiv = to_qiv(v);
     QObject *qobj = qmp_input_get_object(qiv, name, true);

     if (qobject_type(qobj) != QTYPE_QNULL) {
         error_setg(errp, QERR_INVALID_PARAMETER_TYPE, name ? name : "null",
                    "null");
     }
 }

 static void qmp_input_optional(Visitor *v, const char *name, bool *present)
 {
     QmpInputVisitor *qiv = to_qiv(v);
     QObject *qobj = qmp_input_get_object(qiv, name, false);

     if (!qobj) {
         *present = false;
         return;
     }

     *present = true;
 }

 static void qmp_input_free(Visitor *v)
 {
     QmpInputVisitor *qiv = to_qiv(v);

     qobject_decref(qiv->root);
     g_free(qiv);
 }

 Visitor *qmp_input_visitor_new(QObject *obj, bool strict)
 {
     QmpInputVisitor *v;

     v = g_malloc0(sizeof(*v));

     v->visitor.type = VISITOR_INPUT;
     v->visitor.start_struct = qmp_input_start_struct;
     v->visitor.check_struct = qmp_input_check_struct;
     v->visitor.end_struct = qmp_input_pop;
     v->visitor.start_list = qmp_input_start_list;
     v->visitor.next_list = qmp_input_next_list;
     v->visitor.end_list = qmp_input_pop;
     v->visitor.start_alternate = qmp_input_start_alternate;
     v->visitor.type_int64 = qmp_input_type_int64;
     v->visitor.type_uint64 = qmp_input_type_uint64;
     v->visitor.type_bool = qmp_input_type_bool;
     v->visitor.type_str = qmp_input_type_str;
     v->visitor.type_number = qmp_input_type_number;
     v->visitor.type_any = qmp_input_type_any;
     v->visitor.type_null = qmp_input_type_null;
     v->visitor.optional = qmp_input_optional;
     v->visitor.free = qmp_input_free;
     v->strict = strict;

     v->root = obj;
     qobject_incref(obj);

     return &v->visitor;
 }
	/*
	* Input Visitor
	*
	* 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/error.h"
	#include "qapi/qmp-input-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"

	#define QIV_STACK_SIZE 1024

	typedef struct StackObject
	{
	QObject obj; / Object being visited */
	void qapi; / sanity check that caller uses same pointer */

	GHashTable h; / If obj is dict: unvisited keys */
	const QListEntry entry; / If obj is list: unvisited tail */
	} StackObject;

	struct QmpInputVisitor
	{
	Visitor visitor;

	/* Root of visit at visitor creation. */
	QObject *root;

	/* Stack of objects being visited (all entries will be either
	* QDict or QList). */
	StackObject stack[QIV_STACK_SIZE];
	int nb_stack;

	/* True to reject parse in visit_end_struct() if unvisited keys remain. */
	bool strict;
	};

	static QmpInputVisitor to_qiv(Visitor v)
	{
	return container_of(v, QmpInputVisitor, visitor);
	}

	static QObject qmp_input_get_object(QmpInputVisitor qiv,
	const char *name,
	bool consume)
	{
	StackObject *tos;
	QObject *qobj;
	QObject *ret;

	if (!qiv->nb_stack) {
	/* Starting at root, name is ignored. */
	return qiv->root;
	}

	/* We are in a container; find the next element. */
	tos = &qiv->stack[qiv->nb_stack - 1];
	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);
	ret = qlist_entry_obj(tos->entry);
	if (consume) {
	tos->entry = qlist_next(tos->entry);
	}
	}

	return ret;
	}

	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 qmp_input_push(QmpInputVisitor qiv, QObject *obj,
	void qapi, Error *errp)
	{
	GHashTable *h;
	StackObject *tos = &qiv->stack[qiv->nb_stack];

	assert(obj);
	if (qiv->nb_stack >= QIV_STACK_SIZE) {
	error_setg(errp, "An internal buffer overran");
	return NULL;
	}

	tos->obj = obj;
	tos->qapi = qapi;
	assert(!tos->h);
	assert(!tos->entry);

	if (qiv->strict && 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 if (qobject_type(obj) == QTYPE_QLIST) {
	tos->entry = qlist_first(qobject_to_qlist(obj));
	}

	qiv->nb_stack++;
	return tos->entry;
	}


	static void qmp_input_check_struct(Visitor v, Error *errp)
	{
	QmpInputVisitor *qiv = to_qiv(v);
	StackObject *tos = &qiv->stack[qiv->nb_stack - 1];

	assert(qiv->nb_stack > 0);

	if (qiv->strict) {
	GHashTable *const top_ht = tos->h;
	if (top_ht) {
	GHashTableIter iter;
	const char *key;

	g_hash_table_iter_init(&iter, top_ht);
	if (g_hash_table_iter_next(&iter, (void **)&key, NULL)) {
	error_setg(errp, QERR_QMP_EXTRA_MEMBER, key);
	}
	}
	}
	}

	static void qmp_input_pop(Visitor v, void *obj)
	{
	QmpInputVisitor *qiv = to_qiv(v);
	StackObject *tos = &qiv->stack[qiv->nb_stack - 1];

	assert(qiv->nb_stack > 0);
	assert(tos->qapi == obj);

	if (qiv->strict) {
	GHashTable * const top_ht = qiv->stack[qiv->nb_stack - 1].h;
	if (top_ht) {
	g_hash_table_unref(top_ht);
	}
	tos->h = NULL;
	}

	qiv->nb_stack--;
	}

	static void qmp_input_start_struct(Visitor v, const char name, void **obj,
	size_t size, Error **errp)
	{
	QmpInputVisitor *qiv = to_qiv(v);
	QObject *qobj = qmp_input_get_object(qiv, name, true);
	Error *err = NULL;

	if (obj) {
	*obj = NULL;
	}
	if (!qobj \|\| qobject_type(qobj) != QTYPE_QDICT) {
	error_setg(errp, QERR_INVALID_PARAMETER_TYPE, name ? name : "null",
	"QDict");
	return;
	}

	qmp_input_push(qiv, qobj, obj, &err);
	if (err) {
	error_propagate(errp, err);
	return;
	}

	if (obj) {
	*obj = g_malloc0(size);
	}
	}


	static void qmp_input_start_list(Visitor v, const char name,
	GenericList list, size_t size, Error errp)
	{
	QmpInputVisitor *qiv = to_qiv(v);
	QObject *qobj = qmp_input_get_object(qiv, name, true);
	const QListEntry *entry;

	if (!qobj \|\| qobject_type(qobj) != QTYPE_QLIST) {
	if (list) {
	*list = NULL;
	}
	error_setg(errp, QERR_INVALID_PARAMETER_TYPE, name ? name : "null",
	"list");
	return;
	}

	entry = qmp_input_push(qiv, qobj, list, errp);
	if (list) {
	if (entry) {
	*list = g_malloc0(size);
	} else {
	*list = NULL;
	}
	}
	}

	static GenericList qmp_input_next_list(Visitor v, GenericList *tail,
	size_t size)
	{
	QmpInputVisitor *qiv = to_qiv(v);
	StackObject *so = &qiv->stack[qiv->nb_stack - 1];

	if (!so->entry) {
	return NULL;
	}
	tail->next = g_malloc0(size);
	return tail->next;
	}


	static void qmp_input_start_alternate(Visitor v, const char name,
	GenericAlternate **obj, size_t size,
	bool promote_int, Error **errp)
	{
	QmpInputVisitor *qiv = to_qiv(v);
	QObject *qobj = qmp_input_get_object(qiv, name, false);

	if (!qobj) {
	*obj = NULL;
	error_setg(errp, QERR_MISSING_PARAMETER, name ? name : "null");
	return;
	}
	*obj = g_malloc0(size);
	(*obj)->type = qobject_type(qobj);
	if (promote_int && (*obj)->type == QTYPE_QINT) {
	(*obj)->type = QTYPE_QFLOAT;
	}
	}

	static void qmp_input_type_int64(Visitor v, const char name, int64_t *obj,
	Error **errp)
	{
	QmpInputVisitor *qiv = to_qiv(v);
	QInt *qint = qobject_to_qint(qmp_input_get_object(qiv, name, true));

	if (!qint) {
	error_setg(errp, QERR_INVALID_PARAMETER_TYPE, name ? name : "null",
	"integer");
	return;
	}

	*obj = qint_get_int(qint);
	}

	static void qmp_input_type_uint64(Visitor v, const char name, uint64_t *obj,
	Error **errp)
	{
	/* FIXME: qobject_to_qint mishandles values over INT64_MAX */
	QmpInputVisitor *qiv = to_qiv(v);
	QInt *qint = qobject_to_qint(qmp_input_get_object(qiv, name, true));

	if (!qint) {
	error_setg(errp, QERR_INVALID_PARAMETER_TYPE, name ? name : "null",
	"integer");
	return;
	}

	*obj = qint_get_int(qint);
	}

	static void qmp_input_type_bool(Visitor v, const char name, bool *obj,
	Error **errp)
	{
	QmpInputVisitor *qiv = to_qiv(v);
	QBool *qbool = qobject_to_qbool(qmp_input_get_object(qiv, name, true));

	if (!qbool) {
	error_setg(errp, QERR_INVALID_PARAMETER_TYPE, name ? name : "null",
	"boolean");
	return;
	}

	*obj = qbool_get_bool(qbool);
	}

	static void qmp_input_type_str(Visitor v, const char name, char **obj,
	Error **errp)
	{
	QmpInputVisitor *qiv = to_qiv(v);
	QString *qstr = qobject_to_qstring(qmp_input_get_object(qiv, name, true));

	if (!qstr) {
	*obj = NULL;
	error_setg(errp, QERR_INVALID_PARAMETER_TYPE, name ? name : "null",
	"string");
	return;
	}

	*obj = g_strdup(qstring_get_str(qstr));
	}

	static void qmp_input_type_number(Visitor v, const char name, double *obj,
	Error **errp)
	{
	QmpInputVisitor *qiv = to_qiv(v);
	QObject *qobj = qmp_input_get_object(qiv, name, true);
	QInt *qint;
	QFloat *qfloat;

	qint = qobject_to_qint(qobj);
	if (qint) {
	*obj = qint_get_int(qobject_to_qint(qobj));
	return;
	}

	qfloat = qobject_to_qfloat(qobj);
	if (qfloat) {
	*obj = qfloat_get_double(qobject_to_qfloat(qobj));
	return;
	}

	error_setg(errp, QERR_INVALID_PARAMETER_TYPE, name ? name : "null",
	"number");
	}

	static void qmp_input_type_any(Visitor v, const char name, QObject **obj,
	Error **errp)
	{
	QmpInputVisitor *qiv = to_qiv(v);
	QObject *qobj = qmp_input_get_object(qiv, name, true);

	qobject_incref(qobj);
	*obj = qobj;
	}

	static void qmp_input_type_null(Visitor v, const char name, Error **errp)
	{
	QmpInputVisitor *qiv = to_qiv(v);
	QObject *qobj = qmp_input_get_object(qiv, name, true);

	if (qobject_type(qobj) != QTYPE_QNULL) {
	error_setg(errp, QERR_INVALID_PARAMETER_TYPE, name ? name : "null",
	"null");
	}
	}

	static void qmp_input_optional(Visitor v, const char name, bool *present)
	{
	QmpInputVisitor *qiv = to_qiv(v);
	QObject *qobj = qmp_input_get_object(qiv, name, false);

	if (!qobj) {
	*present = false;
	return;
	}

	*present = true;
	}

	static void qmp_input_free(Visitor *v)
	{
	QmpInputVisitor *qiv = to_qiv(v);

	qobject_decref(qiv->root);
	g_free(qiv);
	}

	Visitor qmp_input_visitor_new(QObject obj, bool strict)
	{
	QmpInputVisitor *v;

	v = g_malloc0(sizeof(*v));

	v->visitor.type = VISITOR_INPUT;
	v->visitor.start_struct = qmp_input_start_struct;
	v->visitor.check_struct = qmp_input_check_struct;
	v->visitor.end_struct = qmp_input_pop;
	v->visitor.start_list = qmp_input_start_list;
	v->visitor.next_list = qmp_input_next_list;
	v->visitor.end_list = qmp_input_pop;
	v->visitor.start_alternate = qmp_input_start_alternate;
	v->visitor.type_int64 = qmp_input_type_int64;
	v->visitor.type_uint64 = qmp_input_type_uint64;
	v->visitor.type_bool = qmp_input_type_bool;
	v->visitor.type_str = qmp_input_type_str;
	v->visitor.type_number = qmp_input_type_number;
	v->visitor.type_any = qmp_input_type_any;
	v->visitor.type_null = qmp_input_type_null;
	v->visitor.optional = qmp_input_optional;
	v->visitor.free = qmp_input_free;
	v->strict = strict;

	v->root = obj;
	qobject_incref(obj);

	return &v->visitor;
	}