bt_recno.c

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			break;
		}
		ret = DB_NOTFOUND;
		goto err;
		/* NOTREACHED */
	case DB_GET_BOTH:
	case DB_GET_BOTH_RANGE:
		/*
		 * If we're searching a set of off-page dups, we start
		 * a new linear search from the first record.  Otherwise,
		 * we compare the single data item associated with the
		 * requested record for a match.
		 */
		if (F_ISSET(dbc, DBC_OPD)) {
			cp->recno = 1;
			break;
		}
		/* FALLTHROUGH */
	case DB_SET:
	case DB_SET_RANGE:
		if ((ret = __ram_getno(dbc, key, &cp->recno, 0)) != 0)
			goto err;
		break;
	default:
		ret = __db_unknown_flag(dbp->dbenv, "__ram_c_get", flags);
		goto err;
	}

	/*
	 * For DB_PREV, DB_LAST, DB_SET and DB_SET_RANGE, we have already
	 * called __ram_update() to make sure sufficient records have been
	 * read from the backing source file.  Do it now for DB_CURRENT (if
	 * the current record was deleted we may need more records from the
	 * backing file for a DB_CURRENT operation), DB_FIRST and DB_NEXT.
	 * (We don't have to test for flags == DB_FIRST, because the switch
	 * statement above re-set flags to DB_NEXT in that case.)
	 */
	if ((flags == DB_NEXT || flags == DB_CURRENT) && ((ret =
	    __ram_update(dbc, cp->recno, 0)) != 0) && ret != DB_NOTFOUND)
		goto err;

	for (;; ++cp->recno) {
		/* Search the tree for the record. */
		if ((ret = __bam_rsearch(dbc, &cp->recno,
		    F_ISSET(dbc, DBC_RMW) ? S_FIND_WR : S_FIND,
		    1, &exact)) != 0)
			goto err;
		if (!exact) {
			ret = DB_NOTFOUND;
			goto err;
		}

		/* Copy the page into the cursor. */
		STACK_TO_CURSOR(cp);

		/*
		 * If re-numbering records, the on-page deleted flag means this
		 * record was implicitly created.  If not re-numbering records,
		 * the on-page deleted flag means this record was implicitly
		 * created, or, it was deleted at some time.  Regardless, we
		 * skip such records if doing cursor next/prev operations or
		 * walking through off-page duplicates, and fail if they were
		 * requested explicitly by the application.
		 */
		if (B_DISSET(GET_BKEYDATA(dbp, cp->page, cp->indx)->type))
			switch (flags) {
			case DB_NEXT:
			case DB_PREV:
				(void)__bam_stkrel(dbc, STK_CLRDBC);
				goto retry;
			case DB_GET_BOTH:
			case DB_GET_BOTH_RANGE:
				/*
				 * If we're an OPD tree, we don't care about
				 * matching a record number on a DB_GET_BOTH
				 * -- everything belongs to the same tree.  A
				 * normal recno should give up and return
				 * DB_NOTFOUND if the matching recno is deleted.
				 */
				if (F_ISSET(dbc, DBC_OPD)) {
					(void)__bam_stkrel(dbc, STK_CLRDBC);
					continue;
				}
				ret = DB_NOTFOUND;
				goto err;
			default:
				ret = DB_KEYEMPTY;
				goto err;
			}

		if (flags == DB_GET_BOTH ||
		    flags == DB_GET_BOTHC || flags == DB_GET_BOTH_RANGE) {
			if ((ret = __bam_cmp(dbp, data,
			    cp->page, cp->indx, __bam_defcmp, &cmp)) != 0)
				return (ret);
			if (cmp == 0)
				break;
			if (!F_ISSET(dbc, DBC_OPD)) {
				ret = DB_NOTFOUND;
				goto err;
			}
			(void)__bam_stkrel(dbc, STK_CLRDBC);
		} else
			break;
	}

	/* Return the key if the user didn't give us one. */
	if (!F_ISSET(dbc, DBC_OPD)) {
		if (flags != DB_GET_BOTH && flags != DB_GET_BOTH_RANGE &&
		    flags != DB_SET && flags != DB_SET_RANGE)
			ret = __db_retcopy(dbp->dbenv,
			    key, &cp->recno, sizeof(cp->recno),
			    &dbc->rkey->data, &dbc->rkey->ulen);
		F_SET(key, DB_DBT_ISSET);
	}

	/* The cursor was reset, no further delete adjustment is necessary. */
err:	CD_CLR(cp);

	return (ret);
}

/*
 * __ram_c_put --
 *	Recno cursor->c_put function.
 *
 * PUBLIC: int __ram_c_put __P((DBC *, DBT *, DBT *, u_int32_t, db_pgno_t *));
 */
int
__ram_c_put(dbc, key, data, flags, pgnop)
	DBC *dbc;
	DBT *key, *data;
	u_int32_t flags;
	db_pgno_t *pgnop;
{
	BTREE_CURSOR *cp;
	DB *dbp;
	DB_LSN lsn;
	int exact, nc, ret, t_ret;
	u_int32_t iiflags;
	void *arg;

	COMPQUIET(pgnop, NULL);

	dbp = dbc->dbp;
	cp = (BTREE_CURSOR *)dbc->internal;

	/*
	 * DB_KEYFIRST and DB_KEYLAST mean different things if they're
	 * used in an off-page duplicate tree.  If we're an off-page
	 * duplicate tree, they really mean "put at the beginning of the
	 * tree" and "put at the end of the tree" respectively, so translate
	 * them to something else.
	 */
	if (F_ISSET(dbc, DBC_OPD))
		switch (flags) {
		case DB_KEYFIRST:
			cp->recno = 1;
			flags = DB_BEFORE;
			break;
		case DB_KEYLAST:
			if ((ret = __ram_add(dbc,
			    &cp->recno, data, DB_APPEND, 0)) != 0)
				return (ret);
			if (CURADJ_LOG(dbc) &&
			    (ret = __bam_rcuradj_log(dbp, dbc->txn, &lsn, 0,
			    CA_ICURRENT, cp->root, cp->recno, cp->order)))
				return (ret);
			return (0);
		}

	/*
	 * Handle normal DB_KEYFIRST/DB_KEYLAST;  for a recno, which has
	 * no duplicates, these are identical and mean "put the given
	 * datum at the given recno".
	 *
	 * Note that the code here used to be in __ram_put;  now, we
	 * go through the access-method-common __db_put function, which
	 * handles DB_NOOVERWRITE, so we and __ram_add don't have to.
	 */
	if (flags == DB_KEYFIRST || flags == DB_KEYLAST) {
		ret = __ram_getno(dbc, key, &cp->recno, 1);
		if (ret == 0 || ret == DB_NOTFOUND)
			ret = __ram_add(dbc, &cp->recno, data, 0, 0);
		return (ret);
	}

	/*
	 * If we're putting with a cursor that's marked C_DELETED, we need to
	 * take special care;  the cursor doesn't "really" reference the item
	 * corresponding to its current recno, but instead is "between" that
	 * record and the current one.  Translate the actual insert into
	 * DB_BEFORE, and let the __ram_ca work out the gory details of what
	 * should wind up pointing where.
	 */
	if (CD_ISSET(cp))
		iiflags = DB_BEFORE;
	else
		iiflags = flags;

split:	if ((ret = __bam_rsearch(dbc, &cp->recno, S_INSERT, 1, &exact)) != 0)
		goto err;
	/*
	 * An inexact match is okay;  it just means we're one record past the
	 * end, which is reasonable if we're marked deleted.
	 */
	DB_ASSERT(exact || CD_ISSET(cp));

	/* Copy the page into the cursor. */
	STACK_TO_CURSOR(cp);

	ret = __bam_iitem(dbc, key, data, iiflags, 0);
	t_ret = __bam_stkrel(dbc, STK_CLRDBC);

	if (t_ret != 0 && (ret == 0 || ret == DB_NEEDSPLIT))
		ret = t_ret;
	else if (ret == DB_NEEDSPLIT) {
		arg = &cp->recno;
		if ((ret = __bam_split(dbc, arg, NULL)) != 0)
			goto err;
		goto split;
	}
	if (ret != 0)
		goto err;

	switch (flags) {			/* Adjust the cursors. */
	case DB_AFTER:
		nc = __ram_ca(dbc, CA_IAFTER);

		/*
		 * We only need to adjust this cursor forward if we truly added
		 * the item after the current recno, rather than remapping it
		 * to DB_BEFORE.
		 */
		if (iiflags == DB_AFTER)
			++cp->recno;

		/* Only log if __ram_ca found any relevant cursors. */
		if (nc > 0 && CURADJ_LOG(dbc) &&
		    (ret = __bam_rcuradj_log(dbp, dbc->txn, &lsn, 0, CA_IAFTER,
		    cp->root, cp->recno, cp->order)) != 0)
			goto err;
		break;
	case DB_BEFORE:
		nc = __ram_ca(dbc, CA_IBEFORE);
		--cp->recno;

		/* Only log if __ram_ca found any relevant cursors. */
		if (nc > 0 && CURADJ_LOG(dbc) &&
		    (ret = __bam_rcuradj_log(dbp, dbc->txn, &lsn, 0, CA_IBEFORE,
		    cp->root, cp->recno, cp->order)) != 0)
			goto err;
		break;
	case DB_CURRENT:
		/*
		 * We only need to do an adjustment if we actually
		 * added an item, which we only would have done if the
		 * cursor was marked deleted.
		 *
		 * Only log if __ram_ca found any relevant cursors.
		 */
		if (CD_ISSET(cp) && __ram_ca(dbc, CA_ICURRENT) > 0 &&
		    CURADJ_LOG(dbc) &&
		    (ret = __bam_rcuradj_log(dbp, dbc->txn, &lsn, 0,
		    CA_ICURRENT, cp->root, cp->recno, cp->order)) != 0)
			goto err;
		break;
	}

	/* Return the key if we've created a new record. */
	if (!F_ISSET(dbc, DBC_OPD) && (flags == DB_AFTER || flags == DB_BEFORE))
		ret = __db_retcopy(dbp->dbenv, key, &cp->recno,
		    sizeof(cp->recno), &dbc->rkey->data, &dbc->rkey->ulen);

	/* The cursor was reset, no further delete adjustment is necessary. */
err:	CD_CLR(cp);

	return (ret);
}

/*
 * __ram_ca --
 *	Adjust cursors.  Returns the number of relevant cursors.
 *
 * PUBLIC: int __ram_ca __P((DBC *, ca_recno_arg));
 */
int
__ram_ca(dbc_arg, op)
	DBC *dbc_arg;
	ca_recno_arg op;
{
	BTREE_CURSOR *cp, *cp_arg;
	DB *dbp, *ldbp;
	DB_ENV *dbenv;
	DBC *dbc;
	db_recno_t recno;
	int adjusted, found;
	u_int32_t order;

	dbp = dbc_arg->dbp;
	dbenv = dbp->dbenv;
	cp_arg = (BTREE_CURSOR *)dbc_arg->internal;
	recno = cp_arg->recno;

	found = 0;

	/*
	 * It only makes sense to adjust cursors if we're a renumbering
	 * recno;  we should only be called if this is one.
	 */
	DB_ASSERT(F_ISSET(cp_arg, C_RENUMBER));

	MUTEX_THREAD_LOCK(dbenv, dbenv->dblist_mutexp);
	/*
	 * Adjust the cursors.  See the comment in __bam_ca_delete().
	 */
	/*
	 * If we're doing a delete, we need to find the highest
	 * order of any cursor currently pointing at this item,
	 * so we can assign a higher order to the newly deleted
	 * cursor.  Unfortunately, this requires a second pass through
	 * the cursor list.
	 */
	if (op == CA_DELETE) {
		order = 1;
		for (ldbp = __dblist_get(dbenv, dbp->adj_fileid);
		    ldbp != NULL && ldbp->adj_fileid == dbp->adj_fileid;
		    ldbp = LIST_NEXT(ldbp, dblistlinks)) {
			MUTEX_THREAD_LOCK(dbenv, dbp->mutexp);
			for (dbc = TAILQ_FIRST(&ldbp->active_queue);
			    dbc != NULL; dbc = TAILQ_NEXT(dbc, links)) {
				cp = (BTREE_CURSOR *)dbc->internal;
				if (cp_arg->root == cp->root &&
				    recno == cp->recno && CD_ISSET(cp) &&
				    order <= cp->order)
					order = cp->order + 1;
			}
			MUTEX_THREAD_UNLOCK(dbenv, dbp->mutexp);
		}
	} else
		order = INVALID_ORDER;

	/* Now go through and do the actual adjustments. */
	for (ldbp = __dblist_get(dbenv, dbp->adj_fileid);
	    ldbp != NULL && ldbp->adj_fileid == dbp->adj_fileid;
	    ldbp = LIST_NEXT(ldbp, dblistlinks)) {
		MUTEX_THREAD_LOCK(dbenv, dbp->mutexp);
		for (dbc = TAILQ_FIRST(&ldbp->active_queue);
		    dbc != NULL; dbc = TAILQ_NEXT(dbc, links)) {
			cp = (BTREE_CURSOR *)dbc->internal;
			if (cp_arg->root != cp->root)
				continue;
			++found;
			adjusted = 0;
			switch (op) {
			case CA_DELETE:
				if (recno < cp->recno) {
					--cp->recno;
					/*
					 * If the adjustment made them equal,
					 * we have to merge the orders.
					 */
					if (recno == cp->recno && CD_ISSET(cp))
						cp->order += order;
				} else if (recno == cp->recno &&
				    !CD_ISSET(cp)) {
					CD_SET(cp);
					cp->order = order;
				}
				break;
			case CA_IBEFORE:
				/*
				 * IBEFORE is just like IAFTER, except that we
				 * adjust cursors on the current record too.
				 */
				if (C_EQUAL(cp_arg, cp)) {
					++cp->recno;
					adjusted = 1;
				}
				goto iafter;
			case CA_ICURRENT:

				/*
				 * If the original cursor wasn't deleted, we
				 * just did a replacement and so there's no
				 * need to adjust anything--we shouldn't have
				 * gotten this far.  Otherwise, we behave
				 * much like an IAFTER, except that all
				 * cursors pointing to the current item get
				 * marked undeleted and point to the new
				 * item.
				 */
				DB_ASSERT(CD_ISSET(cp_arg));
				if (C_EQUAL(cp_arg, cp)) {
					CD_CLR(cp);
					break;
				}
				/* FALLTHROUGH */
			case CA_IAFTER:
iafter:				if (!adjusted && C_LESSTHAN(cp_arg, cp)) {
					++cp->recno;
					adjusted = 1;
				}
				if (recno == cp->recno && adjusted)
					/*
					 * If we've moved this cursor's recno,
					 * split its order number--i.e.,
					 * decrement it by enough so that
					 * the lowest cursor moved has order 1.
					 * cp_arg->order is the split point,
					 * so decrement by one less than that.
					 */
					cp->order -= (cp_arg->order - 1);
				break;
			}
		}
		MUTEX_THREAD_UNLOCK(dbp->dbenv, dbp->mutexp);
	}
	MUTEX_THREAD_UNLOCK(dbenv, dbenv->dblist_mutexp);

	return (found);
}

/*
 * __ram_getno --
 *	Check the user's record number, and make sure we've seen it.
 *
 * PUBLIC: int __ram_getno __P((DBC *, const DBT *, db_recno_t *, int));
 */
int
__ram_getno(dbc, key, rep, can_create)
	DBC *dbc;
	const DBT *key;
	db_recno_t *rep;
	int can_create;
{
	DB *dbp;
	db_recno_t recno;

	dbp = dbc->dbp;

	/* Check the user's record number. */
	if ((recno = *(db_recno_t *)key->data) == 0) {