mirror of
https://github.com/xemu-project/xemu.git
synced 2024-11-27 13:30:52 +00:00
8cad15b156
Add simple transaction API to use in further update of block graph operations. Supposed usage is: - "prepare" is main function of the action and it should make the main effect of the action to be visible for the following actions, keeping possibility of roll-back, saving necessary things in action state, which is prepended to the action list (to do that, prepare func should call tran_add()). So, driver struct doesn't include "prepare" field, as it is supposed to be called directly. - commit/rollback is supposed to be called for the list of action states, to commit/rollback all the actions in reverse order - When possible "commit" should not make visible effect for other actions, which make possible transparent logical interaction between actions. Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Message-Id: <20210428151804.439460-9-vsementsov@virtuozzo.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
97 lines
2.2 KiB
C
97 lines
2.2 KiB
C
/*
|
|
* Simple transactions API
|
|
*
|
|
* Copyright (c) 2021 Virtuozzo International GmbH.
|
|
*
|
|
* Author:
|
|
* Sementsov-Ogievskiy Vladimir <vsementsov@virtuozzo.com>
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License as published by
|
|
* the Free Software Foundation; either version 2 of the License, or
|
|
* (at your option) any later version.
|
|
*
|
|
* This program is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
* GNU General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU General Public License
|
|
* along with this program. If not, see <http://www.gnu.org/licenses/>.
|
|
*/
|
|
|
|
#include "qemu/osdep.h"
|
|
|
|
#include "qemu/transactions.h"
|
|
#include "qemu/queue.h"
|
|
|
|
typedef struct TransactionAction {
|
|
TransactionActionDrv *drv;
|
|
void *opaque;
|
|
QSLIST_ENTRY(TransactionAction) entry;
|
|
} TransactionAction;
|
|
|
|
struct Transaction {
|
|
QSLIST_HEAD(, TransactionAction) actions;
|
|
};
|
|
|
|
Transaction *tran_new(void)
|
|
{
|
|
Transaction *tran = g_new(Transaction, 1);
|
|
|
|
QSLIST_INIT(&tran->actions);
|
|
|
|
return tran;
|
|
}
|
|
|
|
void tran_add(Transaction *tran, TransactionActionDrv *drv, void *opaque)
|
|
{
|
|
TransactionAction *act;
|
|
|
|
act = g_new(TransactionAction, 1);
|
|
*act = (TransactionAction) {
|
|
.drv = drv,
|
|
.opaque = opaque
|
|
};
|
|
|
|
QSLIST_INSERT_HEAD(&tran->actions, act, entry);
|
|
}
|
|
|
|
void tran_abort(Transaction *tran)
|
|
{
|
|
TransactionAction *act, *next;
|
|
|
|
QSLIST_FOREACH_SAFE(act, &tran->actions, entry, next) {
|
|
if (act->drv->abort) {
|
|
act->drv->abort(act->opaque);
|
|
}
|
|
|
|
if (act->drv->clean) {
|
|
act->drv->clean(act->opaque);
|
|
}
|
|
|
|
g_free(act);
|
|
}
|
|
|
|
g_free(tran);
|
|
}
|
|
|
|
void tran_commit(Transaction *tran)
|
|
{
|
|
TransactionAction *act, *next;
|
|
|
|
QSLIST_FOREACH_SAFE(act, &tran->actions, entry, next) {
|
|
if (act->drv->commit) {
|
|
act->drv->commit(act->opaque);
|
|
}
|
|
|
|
if (act->drv->clean) {
|
|
act->drv->clean(act->opaque);
|
|
}
|
|
|
|
g_free(act);
|
|
}
|
|
|
|
g_free(tran);
|
|
}
|