qemu-e2k/include/qom/object_interfaces.h
Markus Armbruster 51b9b478cc qom: -object error messages lost location, restore it
qemu_opts_foreach() runs its callback with the error location set to
the option's location.  Any errors the callback reports use the
option's location automatically.

Commit 90998d5 moved the actual error reporting from "inside"
qemu_opts_foreach() to after it.  Here's a typical hunk:

	 if (qemu_opts_foreach(qemu_find_opts("object"),
    -                          object_create,
    -                          object_create_initial, NULL)) {
    +                          user_creatable_add_opts_foreach,
    +                          object_create_initial, &err)) {
    +        error_report_err(err);
	     exit(1);
	 }

Before, object_create() reports from within qemu_opts_foreach(), using
the option's location.  Afterwards, we do it after
qemu_opts_foreach(), using whatever location happens to be current
there.  Commonly a "none" location.

This is because Error objects don't have location information.
Problematic.

Reproducer:

    $ qemu-system-x86_64 -nodefaults -display none -object secret,id=foo,foo=bar
    qemu-system-x86_64: Property '.foo' not found

Note no location.  This commit restores it:

    qemu-system-x86_64: -object secret,id=foo,foo=bar: Property '.foo' not found

Note that the qemu_opts_foreach() bug just fixed could mask the bug
here: if the location it leaves dangling hasn't been clobbered, yet,
it's the correct one.

Reported-by: Eric Blake <eblake@redhat.com>
Cc: Daniel P. Berrange <berrange@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <1461767349-15329-4-git-send-email-armbru@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
[Paragraph on Error added to commit message]
2016-04-28 08:19:36 +02:00

169 lines
5.5 KiB
C

#ifndef OBJECT_INTERFACES_H
#define OBJECT_INTERFACES_H
#include "qom/object.h"
#include "qapi/qmp/qdict.h"
#include "qapi/visitor.h"
#define TYPE_USER_CREATABLE "user-creatable"
#define USER_CREATABLE_CLASS(klass) \
OBJECT_CLASS_CHECK(UserCreatableClass, (klass), \
TYPE_USER_CREATABLE)
#define USER_CREATABLE_GET_CLASS(obj) \
OBJECT_GET_CLASS(UserCreatableClass, (obj), \
TYPE_USER_CREATABLE)
#define USER_CREATABLE(obj) \
INTERFACE_CHECK(UserCreatable, (obj), \
TYPE_USER_CREATABLE)
typedef struct UserCreatable {
/* <private> */
Object Parent;
} UserCreatable;
/**
* UserCreatableClass:
* @parent_class: the base class
* @complete: callback to be called after @obj's properties are set.
* @can_be_deleted: callback to be called before an object is removed
* to check if @obj can be removed safely.
*
* Interface is designed to work with -object/object-add/object_add
* commands.
* Interface is mandatory for objects that are designed to be user
* creatable (i.e. -object/object-add/object_add, will accept only
* objects that inherit this interface).
*
* Interface also provides an optional ability to do the second
* stage * initialization of the object after its properties were
* set.
*
* For objects created without using -object/object-add/object_add,
* @user_creatable_complete() wrapper should be called manually if
* object's type implements USER_CREATABLE interface and needs
* complete() callback to be called.
*/
typedef struct UserCreatableClass {
/* <private> */
InterfaceClass parent_class;
/* <public> */
void (*complete)(UserCreatable *uc, Error **errp);
bool (*can_be_deleted)(UserCreatable *uc, Error **errp);
} UserCreatableClass;
/**
* user_creatable_complete:
* @obj: the object whose complete() method is called if defined
* @errp: if an error occurs, a pointer to an area to store the error
*
* Wrapper to call complete() method if one of types it's inherited
* from implements USER_CREATABLE interface, otherwise the call does
* nothing.
*/
void user_creatable_complete(Object *obj, Error **errp);
/**
* user_creatable_can_be_deleted:
* @uc: the object whose can_be_deleted() method is called if implemented
* @errp: if an error occurs, a pointer to an area to store the error
*
* Wrapper to call can_be_deleted() method if one of types it's inherited
* from implements USER_CREATABLE interface.
*/
bool user_creatable_can_be_deleted(UserCreatable *uc, Error **errp);
/**
* user_creatable_add:
* @qdict: the object definition
* @v: the visitor
* @errp: if an error occurs, a pointer to an area to store the error
*
* Create an instance of the user creatable object whose type
* is defined in @qdict by the 'qom-type' field, placing it
* in the object composition tree with name provided by the
* 'id' field. The remaining fields in @qdict are used to
* initialize the object properties.
*
* Returns: the newly created object or NULL on error
*/
Object *user_creatable_add(const QDict *qdict,
Visitor *v, Error **errp);
/**
* user_creatable_add_type:
* @type: the object type name
* @id: the unique ID for the object
* @qdict: the object properties
* @v: the visitor
* @errp: if an error occurs, a pointer to an area to store the error
*
* Create an instance of the user creatable object @type, placing
* it in the object composition tree with name @id, initializing
* it with properties from @qdict
*
* Returns: the newly created object or NULL on error
*/
Object *user_creatable_add_type(const char *type, const char *id,
const QDict *qdict,
Visitor *v, Error **errp);
/**
* user_creatable_add_opts:
* @opts: the object definition
* @errp: if an error occurs, a pointer to an area to store the error
*
* Create an instance of the user creatable object whose type
* is defined in @opts by the 'qom-type' option, placing it
* in the object composition tree with name provided by the
* 'id' field. The remaining options in @opts are used to
* initialize the object properties.
*
* Returns: the newly created object or NULL on error
*/
Object *user_creatable_add_opts(QemuOpts *opts, Error **errp);
/**
* user_creatable_add_opts_predicate:
* @type: the QOM type to be added
*
* A callback function to determine whether an object
* of type @type should be created. Instances of this
* callback should be passed to user_creatable_add_opts_foreach
*/
typedef bool (*user_creatable_add_opts_predicate)(const char *type);
/**
* user_creatable_add_opts_foreach:
* @opaque: a user_creatable_add_opts_predicate callback or NULL
* @opts: options to create
* @errp: unused
*
* An iterator callback to be used in conjunction with
* the qemu_opts_foreach() method for creating a list of
* objects from a set of QemuOpts
*
* The @opaque parameter can be passed a user_creatable_add_opts_predicate
* callback to filter which types of object are created during iteration.
* When it fails, report the error.
*
* Returns: 0 on success, -1 when an error was reported.
*/
int user_creatable_add_opts_foreach(void *opaque,
QemuOpts *opts, Error **errp);
/**
* user_creatable_del:
* @id: the unique ID for the object
* @errp: if an error occurs, a pointer to an area to store the error
*
* Delete an instance of the user creatable object identified
* by @id.
*/
void user_creatable_del(const char *id, Error **errp);
#endif