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/*
* __PREF_FUNC_recover --
* Recovery function for FUNC.
*
* PUBLIC: int __PREF_FUNC_recover
* PUBLIC: __P((DB_ENV *, DBT *, DB_LSN *, db_recops, void *));
*/
int
__PREF_FUNC_recover(dbenv, dbtp, lsnp, op, info)
DB_ENV *dbenv;
DBT *dbtp;
DB_LSN *lsnp;
db_recops op;
void *info;
{
__PREF_FUNC_args *argp;
DB *file_dbp;
DBC *dbc;
DB_MPOOLFILE *mpf;
PAGE *pagep;
int cmp_n, cmp_p, modified, ret;
REC_PRINT(__PREF_FUNC_print);
REC_INTRO(__PREF_FUNC_read);
if ((ret = memp_fget(mpf, &argp->pgno, 0, &pagep)) != 0)
if (DB_REDO(op)) {
if ((ret = memp_fget(mpf,
&argp->pgno, DB_MPOOL_CREATE, &pagep)) != 0)
goto out;
} else {
*lsnp = argp->prev_lsn;
ret = 0;
goto out;
}
modified = 0;
cmp_n = log_compare(lsnp, &LSN(pagep));
/*
* Use this when there is something like "pagelsn" in the argp
* structure. Sometimes, you might need to compare meta-data
* lsn's instead.
*
* cmp_p = log_compare(&LSN(pagep), argp->pagelsn);
*/
if (cmp_p == 0 && DB_REDO(op)) {
/* Need to redo update described. */
modified = 1;
} else if (cmp_n == 0 && !DB_REDO(op)) {
/* Need to undo update described. */
modified = 1;
}
if (ret = memp_fput(mpf, pagep, modified ? DB_MPOOL_DIRTY : 0))
goto out;
*lsnp = argp->prev_lsn;
ret = 0;
out: REC_CLOSE;
}
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