65cd9064e1
Using error_is_set(ERRP) to find out whether a function failed is
either wrong, fragile, or unnecessarily opaque. It's wrong when ERRP
may be null, because errors go undetected when it is. It's fragile
when proving ERRP non-null involves a non-local argument. Else, it's
unnecessarily opaque (see commit 84d18f0).
I guess the error_is_set(errp) in the ObjectProperty set() methods are
merely fragile right now, because I can't find a call chain that
passes a null errp argument.
Make the code more robust and more obviously correct: receive the
error in a local variable, then propagate it through the parameter.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Andreas Färber <afaerber@suse.de>
110 lines
2.5 KiB
C
110 lines
2.5 KiB
C
/*
|
|
* QEMU Random Number Generator Backend
|
|
*
|
|
* Copyright IBM, Corp. 2012
|
|
*
|
|
* Authors:
|
|
* Anthony Liguori <aliguori@us.ibm.com>
|
|
*
|
|
* This work is licensed under the terms of the GNU GPL, version 2 or later.
|
|
* See the COPYING file in the top-level directory.
|
|
*/
|
|
|
|
#include "sysemu/rng.h"
|
|
#include "qapi/qmp/qerror.h"
|
|
#include "qom/object_interfaces.h"
|
|
|
|
void rng_backend_request_entropy(RngBackend *s, size_t size,
|
|
EntropyReceiveFunc *receive_entropy,
|
|
void *opaque)
|
|
{
|
|
RngBackendClass *k = RNG_BACKEND_GET_CLASS(s);
|
|
|
|
if (k->request_entropy) {
|
|
k->request_entropy(s, size, receive_entropy, opaque);
|
|
}
|
|
}
|
|
|
|
void rng_backend_cancel_requests(RngBackend *s)
|
|
{
|
|
RngBackendClass *k = RNG_BACKEND_GET_CLASS(s);
|
|
|
|
if (k->cancel_requests) {
|
|
k->cancel_requests(s);
|
|
}
|
|
}
|
|
|
|
static bool rng_backend_prop_get_opened(Object *obj, Error **errp)
|
|
{
|
|
RngBackend *s = RNG_BACKEND(obj);
|
|
|
|
return s->opened;
|
|
}
|
|
|
|
static void rng_backend_complete(UserCreatable *uc, Error **errp)
|
|
{
|
|
object_property_set_bool(OBJECT(uc), true, "opened", errp);
|
|
}
|
|
|
|
static void rng_backend_prop_set_opened(Object *obj, bool value, Error **errp)
|
|
{
|
|
RngBackend *s = RNG_BACKEND(obj);
|
|
RngBackendClass *k = RNG_BACKEND_GET_CLASS(s);
|
|
Error *local_err = NULL;
|
|
|
|
if (value == s->opened) {
|
|
return;
|
|
}
|
|
|
|
if (!value && s->opened) {
|
|
error_set(errp, QERR_PERMISSION_DENIED);
|
|
return;
|
|
}
|
|
|
|
if (k->opened) {
|
|
k->opened(s, &local_err);
|
|
if (local_err) {
|
|
error_propagate(errp, local_err);
|
|
return;
|
|
}
|
|
}
|
|
|
|
s->opened = true;
|
|
}
|
|
|
|
static void rng_backend_init(Object *obj)
|
|
{
|
|
object_property_add_bool(obj, "opened",
|
|
rng_backend_prop_get_opened,
|
|
rng_backend_prop_set_opened,
|
|
NULL);
|
|
}
|
|
|
|
static void rng_backend_class_init(ObjectClass *oc, void *data)
|
|
{
|
|
UserCreatableClass *ucc = USER_CREATABLE_CLASS(oc);
|
|
|
|
ucc->complete = rng_backend_complete;
|
|
}
|
|
|
|
static const TypeInfo rng_backend_info = {
|
|
.name = TYPE_RNG_BACKEND,
|
|
.parent = TYPE_OBJECT,
|
|
.instance_size = sizeof(RngBackend),
|
|
.instance_init = rng_backend_init,
|
|
.class_size = sizeof(RngBackendClass),
|
|
.class_init = rng_backend_class_init,
|
|
.abstract = true,
|
|
.interfaces = (InterfaceInfo[]) {
|
|
{ TYPE_USER_CREATABLE },
|
|
{ }
|
|
}
|
|
};
|
|
|
|
static void register_types(void)
|
|
{
|
|
type_register_static(&rng_backend_info);
|
|
}
|
|
|
|
type_init(register_types);
|