Invoke the transaction drivers' .clean() methods only after all .commit() or .abort() handlers are done. This makes it easier to have nested transactions where the top-level transactions pass objects to lower transactions that the latter can still use throughout their commit/abort phases, while the top-level transaction keeps a reference that is released in its .clean() method. (Before this commit, that is also possible, but the top-level transaction would need to take care to invoke tran_add() before the lower-level transaction does. This commit makes the ordering irrelevant, which is just a bit nicer.) Signed-off-by: Hanna Reitz <hreitz@redhat.com> Message-Id: <20211111120829.81329-8-hreitz@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> Message-Id: <20211115145409.176785-8-kwolf@redhat.com> Signed-off-by: Hanna Reitz <hreitz@redhat.com>
		
			
				
	
	
		
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			101 lines
		
	
	
		
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			C
		
	
	
	
	
	
/*
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 * Simple transactions API
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 *
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 * Copyright (c) 2021 Virtuozzo International GmbH.
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 *
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 * Author:
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 *  Sementsov-Ogievskiy Vladimir <vsementsov@virtuozzo.com>
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 *
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 * This program is free software; you can redistribute it and/or modify
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 * it under the terms of the GNU General Public License as published by
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 * the Free Software Foundation; either version 2 of the License, or
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 * (at your option) any later version.
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 *
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 * This program is distributed in the hope that it will be useful,
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 * but WITHOUT ANY WARRANTY; without even the implied warranty of
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 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
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 * GNU General Public License for more details.
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 *
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 * You should have received a copy of the GNU General Public License
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 * along with this program. If not, see <http://www.gnu.org/licenses/>.
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 */
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#include "qemu/osdep.h"
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#include "qemu/transactions.h"
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#include "qemu/queue.h"
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typedef struct TransactionAction {
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    TransactionActionDrv *drv;
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    void *opaque;
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    QSLIST_ENTRY(TransactionAction) entry;
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} TransactionAction;
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struct Transaction {
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    QSLIST_HEAD(, TransactionAction) actions;
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};
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Transaction *tran_new(void)
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{
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    Transaction *tran = g_new(Transaction, 1);
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    QSLIST_INIT(&tran->actions);
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    return tran;
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}
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void tran_add(Transaction *tran, TransactionActionDrv *drv, void *opaque)
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{
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    TransactionAction *act;
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    act = g_new(TransactionAction, 1);
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    *act = (TransactionAction) {
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        .drv = drv,
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        .opaque = opaque
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    };
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    QSLIST_INSERT_HEAD(&tran->actions, act, entry);
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}
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void tran_abort(Transaction *tran)
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{
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    TransactionAction *act, *next;
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    QSLIST_FOREACH(act, &tran->actions, entry) {
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        if (act->drv->abort) {
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            act->drv->abort(act->opaque);
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        }
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    }
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    QSLIST_FOREACH_SAFE(act, &tran->actions, entry, next) {
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        if (act->drv->clean) {
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            act->drv->clean(act->opaque);
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        }
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        g_free(act);
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    }
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    g_free(tran);
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}
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void tran_commit(Transaction *tran)
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{
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    TransactionAction *act, *next;
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    QSLIST_FOREACH(act, &tran->actions, entry) {
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        if (act->drv->commit) {
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            act->drv->commit(act->opaque);
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        }
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    }
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    QSLIST_FOREACH_SAFE(act, &tran->actions, entry, next) {
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        if (act->drv->clean) {
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            act->drv->clean(act->opaque);
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        }
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        g_free(act);
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    }
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    g_free(tran);
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}
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