diff options
Diffstat (limited to 'storage/innobase/include/btr0pcur.h')
| -rw-r--r-- | storage/innobase/include/btr0pcur.h | 32 |
1 files changed, 22 insertions, 10 deletions
diff --git a/storage/innobase/include/btr0pcur.h b/storage/innobase/include/btr0pcur.h index a8eaac4690b..973fae382ab 100644 --- a/storage/innobase/include/btr0pcur.h +++ b/storage/innobase/include/btr0pcur.h @@ -1,6 +1,6 @@ /***************************************************************************** -Copyright (c) 1996, 2011, Oracle and/or its affiliates. All Rights Reserved. +Copyright (c) 1996, 2012, Oracle and/or its affiliates. All Rights Reserved. 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 @@ -146,13 +146,16 @@ UNIV_INLINE void btr_pcur_open_at_index_side( /*========================*/ - ibool from_left, /*!< in: TRUE if open to the low end, - FALSE if to the high end */ + bool from_left, /*!< in: true if open to the low end, + false if to the high end */ dict_index_t* index, /*!< in: index */ ulint latch_mode, /*!< in: latch mode */ - btr_pcur_t* pcur, /*!< in: cursor */ - ibool do_init, /*!< in: TRUE if should be initialized */ - mtr_t* mtr); /*!< in: mtr */ + btr_pcur_t* pcur, /*!< in/out: cursor */ + bool init_pcur, /*!< in: whether to initialize pcur */ + ulint level, /*!< in: level to search for + (0=leaf) */ + mtr_t* mtr) /*!< in/out: mini-transaction */ + __attribute__((nonnull)); /**************************************************************//** Gets the up_match value for a pcur after a search. @return number of matched fields at the cursor or to the right if @@ -209,8 +212,17 @@ btr_pcur_open_at_rnd_pos_func( #define btr_pcur_open_at_rnd_pos(i,l,c,m) \ btr_pcur_open_at_rnd_pos_func(i,l,c,__FILE__,__LINE__,m) /**************************************************************//** -Frees the possible old_rec_buf buffer of a persistent cursor and sets the -latch mode of the persistent cursor to BTR_NO_LATCHES. */ +Frees the possible memory heap of a persistent cursor and sets the latch +mode of the persistent cursor to BTR_NO_LATCHES. +WARNING: this function does not release the latch on the page where the +cursor is currently positioned. The latch is acquired by the +"move to next/previous" family of functions. Since recursive shared locks +are not allowed, you must take care (if using the cursor in S-mode) to +manually release the latch by either calling +btr_leaf_page_release(btr_pcur_get_block(&pcur), pcur.latch_mode, mtr) +or by committing the mini-transaction right after btr_pcur_close(). +A subsequent attempt to crawl the same page in the same mtr would cause +an assertion failure. */ UNIV_INLINE void btr_pcur_close( @@ -452,14 +464,14 @@ btr_pcur_move_to_prev_on_page( /* The persistent B-tree cursor structure. This is used mainly for SQL selects, updates, and deletes. */ -struct btr_pcur_struct{ +struct btr_pcur_t{ btr_cur_t btr_cur; /*!< a B-tree cursor */ ulint latch_mode; /*!< see TODO note below! BTR_SEARCH_LEAF, BTR_MODIFY_LEAF, BTR_MODIFY_TREE, or BTR_NO_LATCHES, depending on the latching state of the page and tree where the cursor is - positioned; the last value means that + positioned; BTR_NO_LATCHES means that the cursor is not currently positioned: we say then that the cursor is detached; it can be restored to |