hash.c

这是linux下运行的mysql软件包,可用于linux 下安装 php + mysql + apach 的网络配置

				    nval->doff + nval->dlen, len);
				p += len;
			}

			/* Final size. */
			memcpy(p, &newsize, sizeof(db_indx_t));

			/*
			 * Make sure that the caller isn't corrupting
			 * the sort order.
			 */
			if (dbp->dup_compare != NULL) {
				tmp_val2.data =
				    (u_int8_t *)newrec + sizeof(db_indx_t);
				tmp_val2.size = newsize;
				if (dbp->dup_compare(
				    dbp, &tmp_val, &tmp_val2) != 0) {
					(void)__os_free(dbenv, newrec);
					return (__db_duperr(dbp, flags));
				}
			}

			tmp_val2.data = newrec;
			tmp_val2.size = DUP_SIZE(newsize);
			tmp_val2.doff = hcp->dup_off;
			tmp_val2.dlen = DUP_SIZE(hcp->dup_len);

			ret = __ham_replpair(dbc, &tmp_val2, 0);
			(void)__os_free(dbenv, newrec);

			/* Update cursor */
			if (ret != 0)
				return (ret);

			if (newsize > nondup_size)
				hcp->dup_tlen += (newsize - nondup_size);
			else
				hcp->dup_tlen -= (nondup_size - newsize);
			hcp->dup_len = DUP_SIZE(newsize);
			return (0);
		} else {
			/* Check whether we need to convert to off page. */
			if (ISBIG(hcp,
			    hcp->dup_tlen - hcp->dup_len + nval->size)) {
				if ((ret = __ham_dup_convert(dbc)) != 0)
					return (ret);
				return (hcp->opd->c_am_put(hcp->opd,
				    NULL, nval, flags, NULL));
			}

			/* Make sure we maintain sort order. */
			if (dbp->dup_compare != NULL) {
				tmp_val2.data =
				    HKEYDATA_DATA(H_PAIRDATA(dbp, hcp->page,
				    hcp->indx)) + hcp->dup_off +
				    sizeof(db_indx_t);
				tmp_val2.size = hcp->dup_len;
				if (dbp->dup_compare(dbp, nval, &tmp_val2) != 0)
					return (EINVAL);
			}
			/* Overwriting a complete duplicate. */
			if ((ret =
			    __ham_make_dup(dbp->dbenv, nval, &tmp_val,
			    &dbc->my_rdata.data, &dbc->my_rdata.ulen)) != 0)
				return (ret);
			/* Now fix what we are replacing. */
			tmp_val.doff = hcp->dup_off;
			tmp_val.dlen = DUP_SIZE(hcp->dup_len);

			/* Update cursor */
			if (nval->size > hcp->dup_len)
				hcp->dup_tlen += (nval->size - hcp->dup_len);
			else
				hcp->dup_tlen -= (hcp->dup_len - nval->size);
			hcp->dup_len = (db_indx_t)DUP_SIZE(nval->size);
		}
		myval = &tmp_val;
	} else if (!F_ISSET(nval, DB_DBT_PARTIAL)) {
		/* Put/overwrite */
		memcpy(&tmp_val, nval, sizeof(*nval));
		F_SET(&tmp_val, DB_DBT_PARTIAL);
		tmp_val.doff = 0;
		hk = H_PAIRDATA(dbp, hcp->page, hcp->indx);
		if (HPAGE_PTYPE(hk) == H_OFFPAGE)
			memcpy(&tmp_val.dlen,
			    HOFFPAGE_TLEN(hk), sizeof(u_int32_t));
		else
			tmp_val.dlen = LEN_HDATA(dbp, hcp->page,
			    hcp->hdr->dbmeta.pagesize, hcp->indx);
		myval = &tmp_val;
	} else
		/* Regular partial put */
		myval = nval;

	return (__ham_replpair(dbc, myval, 0));
}

/*
 * Given a key and a cursor, sets the cursor to the page/ndx on which
 * the key resides.  If the key is found, the cursor H_OK flag is set
 * and the pagep, bndx, pgno (dpagep, dndx, dpgno) fields are set.
 * If the key is not found, the H_OK flag is not set.  If the sought
 * field is non-0, the pagep, bndx, pgno (dpagep, dndx, dpgno) fields
 * are set indicating where an add might take place.  If it is 0,
 * non of the cursor pointer field are valid.
 */
static int
__ham_lookup(dbc, key, sought, mode, pgnop)
	DBC *dbc;
	const DBT *key;
	u_int32_t sought;
	db_lockmode_t mode;
	db_pgno_t *pgnop;
{
	DB *dbp;
	HASH_CURSOR *hcp;
	db_pgno_t pgno;
	u_int32_t tlen;
	int match, ret;
	u_int8_t *hk, *dk;

	dbp = dbc->dbp;
	hcp = (HASH_CURSOR *)dbc->internal;
	/*
	 * Set up cursor so that we're looking for space to add an item
	 * as we cycle through the pages looking for the key.
	 */
	if ((ret = __ham_item_reset(dbc)) != 0)
		return (ret);
	hcp->seek_size = sought;

	hcp->bucket = __ham_call_hash(dbc, (u_int8_t *)key->data, key->size);
	hcp->pgno = BUCKET_TO_PAGE(hcp, hcp->bucket);

	for (;;) {
		*pgnop = PGNO_INVALID;
		if ((ret = __ham_item_next(dbc, mode, pgnop)) != 0)
			return (ret);

		if (F_ISSET(hcp, H_NOMORE))
			break;

		hk = H_PAIRKEY(dbp, hcp->page, hcp->indx);
		switch (HPAGE_PTYPE(hk)) {
		case H_OFFPAGE:
			memcpy(&tlen, HOFFPAGE_TLEN(hk), sizeof(u_int32_t));
			if (tlen == key->size) {
				memcpy(&pgno,
				    HOFFPAGE_PGNO(hk), sizeof(db_pgno_t));
				if ((ret = __db_moff(dbp,
				    key, pgno, tlen, NULL, &match)) != 0)
					return (ret);
				if (match == 0)
					goto found_key;
			}
			break;
		case H_KEYDATA:
			if (key->size ==
			    LEN_HKEY(dbp, hcp->page, dbp->pgsize, hcp->indx) &&
			    memcmp(key->data,
			    HKEYDATA_DATA(hk), key->size) == 0) {
				/* Found the key, check for data type. */
found_key:			F_SET(hcp, H_OK);
				dk = H_PAIRDATA(dbp, hcp->page, hcp->indx);
				if (HPAGE_PTYPE(dk) == H_OFFDUP)
					memcpy(pgnop, HOFFDUP_PGNO(dk),
					    sizeof(db_pgno_t));
				return (0);
			}
			break;
		case H_DUPLICATE:
		case H_OFFDUP:
			/*
			 * These are errors because keys are never
			 * duplicated, only data items are.
			 */
			return (__db_pgfmt(dbp->dbenv, PGNO(hcp->page)));
		}
	}

	/*
	 * Item was not found.
	 */

	if (sought != 0)
		return (ret);

	return (ret);
}

/*
 * __ham_init_dbt --
 *	Initialize a dbt using some possibly already allocated storage
 *	for items.
 *
 * PUBLIC: int __ham_init_dbt __P((DB_ENV *,
 * PUBLIC:     DBT *, u_int32_t, void **, u_int32_t *));
 */
int
__ham_init_dbt(dbenv, dbt, size, bufp, sizep)
	DB_ENV *dbenv;
	DBT *dbt;
	u_int32_t size;
	void **bufp;
	u_int32_t *sizep;
{
	int ret;

	memset(dbt, 0, sizeof(*dbt));
	if (*sizep < size) {
		if ((ret = __os_realloc(dbenv, size, bufp)) != 0) {
			*sizep = 0;
			return (ret);
		}
		*sizep = size;
	}
	dbt->data = *bufp;
	dbt->size = size;
	return (0);
}

/*
 * Adjust the cursor after an insert or delete.  The cursor passed is
 * the one that was operated upon; we just need to check any of the
 * others.
 *
 * len indicates the length of the item added/deleted
 * add indicates if the item indicated by the cursor has just been
 * added (add == 1) or deleted (add == 0).
 * dup indicates if the addition occurred into a duplicate set.
 *
 * PUBLIC: int __ham_c_update
 * PUBLIC:    __P((DBC *, u_int32_t, int, int));
 */
int
__ham_c_update(dbc, len, add, is_dup)
	DBC *dbc;
	u_int32_t len;
	int add, is_dup;
{
	DB *dbp, *ldbp;
	DBC *cp;
	DB_ENV *dbenv;
	DB_LSN lsn;
	DB_TXN *my_txn;
	HASH_CURSOR *hcp, *lcp;
	int found, ret;
	u_int32_t order;

	dbp = dbc->dbp;
	dbenv = dbp->dbenv;
	hcp = (HASH_CURSOR *)dbc->internal;

	/*
	 * Adjustment will only be logged if this is a subtransaction.
	 * Only subtransactions can abort and effect their parent
	 * transactions cursors.
	 */

	my_txn = IS_SUBTRANSACTION(dbc->txn) ? dbc->txn : NULL;
	found = 0;

	MUTEX_THREAD_LOCK(dbenv, dbenv->dblist_mutexp);

	/*
	 * Calculate the order of this deleted record.
	 * This will be one greater than any cursor that is pointing
	 * at this record and already marked as deleted.
	 */
	order = 0;
	if (!add) {
		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 (cp = TAILQ_FIRST(&ldbp->active_queue); cp != NULL;
			    cp = TAILQ_NEXT(cp, links)) {
				if (cp == dbc || cp->dbtype != DB_HASH)
					continue;
				lcp = (HASH_CURSOR *)cp->internal;
				if (F_ISSET(lcp, H_DELETED) &&
				    hcp->pgno == lcp->pgno &&
				    hcp->indx == lcp->indx &&
				    order <= lcp->order &&
				    (!is_dup || hcp->dup_off == lcp->dup_off))
					order = lcp->order + 1;
			}
			MUTEX_THREAD_UNLOCK(dbenv, dbp->mutexp);
		}
		hcp->order = order;
	}

	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 (cp = TAILQ_FIRST(&ldbp->active_queue); cp != NULL;
		    cp = TAILQ_NEXT(cp, links)) {
			if (cp == dbc || cp->dbtype != DB_HASH)
				continue;

			lcp = (HASH_CURSOR *)cp->internal;

			if (lcp->pgno != hcp->pgno || lcp->indx == NDX_INVALID)
				continue;

			if (my_txn != NULL && cp->txn != my_txn)
				found = 1;

			if (!is_dup) {
				if (add) {
					/*
					 * This routine is not called to add
					 * non-dup records which are always put
					 * at the end.  It is only called from
					 * recovery in this case and the
					 * cursor will be marked deleted.
					 * We are "undeleting" so unmark all
					 * cursors with the same order.
					 */
					if (lcp->indx == hcp->indx &&
					    F_ISSET(lcp, H_DELETED)) {
						if (lcp->order == hcp->order)
							F_CLR(lcp, H_DELETED);
						else if (lcp->order >
						    hcp->order) {

						/*
						 * If we've moved this cursor's
						 * index, 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.
						 */
							lcp->order -=
							    (hcp->order - 1);
							lcp->indx += 2;
						}
					} else if (lcp->indx >= hcp->indx)
						lcp->indx += 2;

				} else {
					if (lcp->indx > hcp->indx) {
						lcp->indx -= 2;
						if (lcp->indx == hcp->indx &&
						    F_ISSET(lcp, H_DELETED))
							lcp->order += order;
					} else if (lcp->indx == hcp->indx &&
					    !F_ISSET(lcp, H_DELETED)) {
						F_SET(lcp, H_DELETED);
						F_CLR(lcp, H_ISDUP);
						lcp->order = order;
					}
				}
			} else if (lcp->indx == hcp->indx) {
				/*
				 * Handle duplicates.  This routine is
				 * only called for on page dups.
				 * Off page dups are handled by btree/rtree
				 * code.
				 */
				if (add) {
					lcp->dup_tlen += len;
					if (lcp->dup_off == hcp->dup_off &&
					    F_ISSET(hcp, H_DELETED) &&
					    F_ISSET(lcp, H_DELETED)) {
						/* Abort of a delete. */
						if (lcp->order == hcp->order)
							F_CLR(lcp, H_DELETED);
						else if (lcp->order >
						    hcp->order) {
							lcp->order -=
							    (hcp->order -1);
							lcp->dup_off += len;
						}
					} else if (lcp->dup_off >= hcp->dup_off)
						lcp->dup_off += len;
				} else {
					lcp->dup_tlen -= len;
					if (lcp->dup_off > hcp->dup_off) {
						lcp->dup_off -= len;
						if (lcp->dup_off ==
						    hcp->dup_off &&
						    F_ISSET(lcp, H_DELETED))
							lcp->order += order;
					} else if (lcp->dup_off ==
					    hcp->dup_off &&
					    !F_ISSET(lcp, H_DELETED)) {
						F_SET(lcp, H_DELETED);
						lcp->order = order;
					}
				}
			}
		}
		MUTEX_THREAD_UNLOCK(dbenv, dbp->mutexp);
	}
	MUTEX_THREAD_UNLOCK(dbenv, dbenv->dblist_mutexp);

	if (found != 0 && DBC_LOGGING(dbc)) {
		if ((ret = __ham_curadj_log(dbp, my_txn, &lsn, 0, hcp->pgno,
		    hcp->indx, len, hcp->dup_off, add, is_dup, order)) != 0)
			return (ret);
	}

	return (0);
}

/*
 * __ham_get_clist --
 *
 * Get a list of cursors either on a particular bucket or on a particular
 * page and index combination.  The former is so that we can update
 * cursors on a split.  The latter is so we can update cursors when we
 * move items off page.
 *
 * PUBLIC: int __ham_get_clist __P((DB *, db_pgno_t, u_int32_t, DBC ***));
 */
int
__ham_get_clist(dbp, pgno, indx, listp)
	DB *dbp;
	db_pgno_t pgno;
	u_int32_t indx;
	DBC ***listp;
{
	DB *ldbp;
	DBC *cp;
	DB_ENV *dbenv;
	int nalloc, nused, ret;

	/*
	 * Assume that finding anything is the exception, so optimize for
	 * the case where there aren't any.
	 */
	nalloc = nused = 0;
	*listp = NULL;
	dbenv = dbp->dbenv;

	MUTEX_THREAD_LOCK(dbenv, dbenv->dblist_mutexp);
	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 (cp = TAILQ_FIRST(&ldbp->active_queue); cp != NULL;
		    cp = TAILQ_NEXT(cp, links))
			/*
			 * We match if cp->pgno matches the specified
			 * pgno, and if either the cp->indx matches
			 * or we weren't given an index.
			 */
			if (cp->internal->pgno == pgno &&
			    (indx == NDX_INVALID ||
			    cp->internal->indx == indx)) {
				if (nused >= nalloc) {
					nalloc += 10;
					if ((ret = __os_realloc(dbp->dbenv,
					    nalloc * sizeof(HASH_CURSOR *),
					    listp)) != 0)
						goto err;
				}
				(*listp)[nused++] = cp;
			}

		MUTEX_THREAD_UNLOCK(dbp->dbenv, dbp->mutexp);
	}
	MUTEX_THREAD_UNLOCK(dbenv, dbenv->dblist_mutexp);

	if (listp != NULL) {
		if (nused >= nalloc) {
			nalloc++;
			if ((ret = __os_realloc(dbp->dbenv,
			    nalloc * sizeof(HASH_CURSOR *), listp)) != 0)
				return (ret);
		}
		(*listp)[nused] = NULL;
	}
	return (0);
err:
	MUTEX_THREAD_UNLOCK(dbp->dbenv, dbp->mutexp);
	MUTEX_THREAD_UNLOCK(dbenv, dbenv->dblist_mutexp);
	return (ret);
}

static int
__ham_c_writelock(dbc)
	DBC *dbc;
{
	DB_ENV *dbenv;
	DB_LOCK tmp_lock;
	HASH_CURSOR *hcp;
	int ret;

	/*
	 * All we need do is acquire the lock and let the off-page
	 * dup tree do its thing.
	 */
	if (!STD_LOCKING(dbc))
		return (0);

	hcp = (HASH_CURSOR *)dbc->internal;
	if ((!LOCK_ISSET(hcp->lock) || hcp->lock_mode == DB_LOCK_READ)) {
		tmp_lock = hcp->lock;
		if ((ret = __ham_lock_bucket(dbc, DB_LOCK_WRITE)) != 0)
			return (ret);
		dbenv = dbc->dbp->dbenv;
		if (LOCK_ISSET(tmp_lock) &&
		    (ret = dbenv->lock_put(dbenv, &tmp_lock)) != 0)
			return (ret);
	}
	return (0);
}