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Diffstat (limited to 'innobase/include/btr0pcur.ic')
| -rw-r--r-- | innobase/include/btr0pcur.ic | 598 |
1 files changed, 598 insertions, 0 deletions
diff --git a/innobase/include/btr0pcur.ic b/innobase/include/btr0pcur.ic new file mode 100644 index 00000000000..7f31f8fe502 --- /dev/null +++ b/innobase/include/btr0pcur.ic @@ -0,0 +1,598 @@ +/****************************************************** +The index tree persistent cursor + +(c) 1996 Innobase Oy + +Created 2/23/1996 Heikki Tuuri +*******************************************************/ + + +/************************************************************* +Gets the rel_pos field for a cursor whose position has been stored. */ +UNIV_INLINE +ulint +btr_pcur_get_rel_pos( +/*=================*/ + /* out: BTR_PCUR_ON, ... */ + btr_pcur_t* cursor) /* in: persistent cursor */ +{ + ut_ad(cursor); + ut_ad(cursor->old_rec); + ut_ad(cursor->old_stored == BTR_PCUR_OLD_STORED); + ut_ad((cursor->pos_state == BTR_PCUR_WAS_POSITIONED) + || (cursor->pos_state == BTR_PCUR_IS_POSITIONED)); + + return(cursor->rel_pos); +} + +/************************************************************* +Sets the mtr field for a pcur. */ +UNIV_INLINE +void +btr_pcur_set_mtr( +/*=============*/ + btr_pcur_t* cursor, /* in: persistent cursor */ + mtr_t* mtr) /* in, own: mtr */ +{ + ut_ad(cursor); + + cursor->mtr = mtr; +} + +/************************************************************* +Gets the mtr field for a pcur. */ +UNIV_INLINE +mtr_t* +btr_pcur_get_mtr( +/*=============*/ + /* out: mtr */ + btr_pcur_t* cursor) /* in: persistent cursor */ +{ + ut_ad(cursor); + + return(cursor->mtr); +} + +/************************************************************* +Returns the btr cursor component of a persistent cursor. */ +UNIV_INLINE +btr_cur_t* +btr_pcur_get_btr_cur( +/*=================*/ + /* out: pointer to btr cursor component */ + btr_pcur_t* cursor) /* in: persistent cursor */ +{ + return(&(cursor->btr_cur)); +} + +/************************************************************* +Returns the page cursor component of a persistent cursor. */ +UNIV_INLINE +page_cur_t* +btr_pcur_get_page_cur( +/*==================*/ + /* out: pointer to page cursor component */ + btr_pcur_t* cursor) /* in: persistent cursor */ +{ + return(btr_cur_get_page_cur(&(cursor->btr_cur))); +} + +/************************************************************* +Returns the page of a persistent cursor. */ +UNIV_INLINE +page_t* +btr_pcur_get_page( +/*==============*/ + /* out: pointer to the page */ + btr_pcur_t* cursor) /* in: persistent cursor */ +{ + ut_ad(cursor->pos_state == BTR_PCUR_IS_POSITIONED); + + return(page_cur_get_page(btr_pcur_get_page_cur(cursor))); +} + +/************************************************************* +Returns the record of a persistent cursor. */ +UNIV_INLINE +rec_t* +btr_pcur_get_rec( +/*=============*/ + /* out: pointer to the record */ + btr_pcur_t* cursor) /* in: persistent cursor */ +{ + ut_ad(cursor->pos_state == BTR_PCUR_IS_POSITIONED); + ut_ad(cursor->latch_mode != BTR_NO_LATCHES); + + return(page_cur_get_rec(btr_pcur_get_page_cur(cursor))); +} + +/****************************************************************** +Gets the up_match value for a pcur after a search. */ +UNIV_INLINE +ulint +btr_pcur_get_up_match( +/*==================*/ + /* out: number of matched fields at the cursor + or to the right if search mode was PAGE_CUR_GE, + otherwise undefined */ + btr_pcur_t* cursor) /* in: memory buffer for persistent cursor */ +{ + btr_cur_t* btr_cursor; + + ut_ad((cursor->pos_state == BTR_PCUR_WAS_POSITIONED) + || (cursor->pos_state == BTR_PCUR_IS_POSITIONED)); + + btr_cursor = btr_pcur_get_btr_cur(cursor); + + ut_ad(btr_cursor->up_match != ULINT_UNDEFINED); + + return(btr_cursor->up_match); +} + +/****************************************************************** +Gets the low_match value for a pcur after a search. */ +UNIV_INLINE +ulint +btr_pcur_get_low_match( +/*===================*/ + /* out: number of matched fields at the cursor + or to the right if search mode was PAGE_CUR_LE, + otherwise undefined */ + btr_pcur_t* cursor) /* in: memory buffer for persistent cursor */ +{ + btr_cur_t* btr_cursor; + + ut_ad((cursor->pos_state == BTR_PCUR_WAS_POSITIONED) + || (cursor->pos_state == BTR_PCUR_IS_POSITIONED)); + + btr_cursor = btr_pcur_get_btr_cur(cursor); + ut_ad(btr_cursor->low_match != ULINT_UNDEFINED); + + return(btr_cursor->low_match); +} + +/************************************************************* +Checks if the persistent cursor is after the last user record on +a page. */ +UNIV_INLINE +ibool +btr_pcur_is_after_last_on_page( +/*===========================*/ + btr_pcur_t* cursor, /* in: persistent cursor */ + mtr_t* mtr) /* in: mtr */ +{ + UT_NOT_USED(mtr); + ut_ad(cursor->pos_state == BTR_PCUR_IS_POSITIONED); + ut_ad(cursor->latch_mode != BTR_NO_LATCHES); + + return(page_cur_is_after_last(btr_pcur_get_page_cur(cursor))); +} + +/************************************************************* +Checks if the persistent cursor is before the first user record on +a page. */ +UNIV_INLINE +ibool +btr_pcur_is_before_first_on_page( +/*=============================*/ + btr_pcur_t* cursor, /* in: persistent cursor */ + mtr_t* mtr) /* in: mtr */ +{ + UT_NOT_USED(mtr); + ut_ad(cursor->pos_state == BTR_PCUR_IS_POSITIONED); + ut_ad(cursor->latch_mode != BTR_NO_LATCHES); + + return(page_cur_is_before_first(btr_pcur_get_page_cur(cursor))); +} + +/************************************************************* +Checks if the persistent cursor is on a user record. */ +UNIV_INLINE +ibool +btr_pcur_is_on_user_rec( +/*====================*/ + btr_pcur_t* cursor, /* in: persistent cursor */ + mtr_t* mtr) /* in: mtr */ +{ + ut_ad(cursor->pos_state == BTR_PCUR_IS_POSITIONED); + ut_ad(cursor->latch_mode != BTR_NO_LATCHES); + + if ((btr_pcur_is_before_first_on_page(cursor, mtr)) + || (btr_pcur_is_after_last_on_page(cursor, mtr))) { + + return(FALSE); + } + + return(TRUE); +} + +/************************************************************* +Checks if the persistent cursor is before the first user record in +the index tree. */ +UNIV_INLINE +ibool +btr_pcur_is_before_first_in_tree( +/*=============================*/ + btr_pcur_t* cursor, /* in: persistent cursor */ + mtr_t* mtr) /* in: mtr */ +{ + ut_ad(cursor->pos_state == BTR_PCUR_IS_POSITIONED); + ut_ad(cursor->latch_mode != BTR_NO_LATCHES); + + if (btr_page_get_prev(btr_pcur_get_page(cursor), mtr) != FIL_NULL) { + + return(FALSE); + } + + return(page_cur_is_before_first(btr_pcur_get_page_cur(cursor))); +} + +/************************************************************* +Checks if the persistent cursor is after the last user record in +the index tree. */ +UNIV_INLINE +ibool +btr_pcur_is_after_last_in_tree( +/*===========================*/ + btr_pcur_t* cursor, /* in: persistent cursor */ + mtr_t* mtr) /* in: mtr */ +{ + ut_ad(cursor->pos_state == BTR_PCUR_IS_POSITIONED); + ut_ad(cursor->latch_mode != BTR_NO_LATCHES); + + if (btr_page_get_next(btr_pcur_get_page(cursor), mtr) != FIL_NULL) { + + return(FALSE); + } + + return(page_cur_is_after_last(btr_pcur_get_page_cur(cursor))); +} + +/************************************************************* +Moves the persistent cursor to the next record on the same page. */ +UNIV_INLINE +void +btr_pcur_move_to_next_on_page( +/*==========================*/ + btr_pcur_t* cursor, /* in: persistent cursor */ + mtr_t* mtr) /* in: mtr */ +{ + UT_NOT_USED(mtr); + ut_ad(cursor->pos_state == BTR_PCUR_IS_POSITIONED); + ut_ad(cursor->latch_mode != BTR_NO_LATCHES); + + page_cur_move_to_next(btr_pcur_get_page_cur(cursor)); + + cursor->old_stored = BTR_PCUR_OLD_NOT_STORED; +} + +/************************************************************* +Moves the persistent cursor to the previous record on the same page. */ +UNIV_INLINE +void +btr_pcur_move_to_prev_on_page( +/*==========================*/ + btr_pcur_t* cursor, /* in: persistent cursor */ + mtr_t* mtr) /* in: mtr */ +{ + UT_NOT_USED(mtr); + ut_ad(cursor->pos_state == BTR_PCUR_IS_POSITIONED); + ut_ad(cursor->latch_mode != BTR_NO_LATCHES); + + page_cur_move_to_prev(btr_pcur_get_page_cur(cursor)); + + cursor->old_stored = BTR_PCUR_OLD_NOT_STORED; +} + +/************************************************************* +Moves the persistent cursor to the next user record in the tree. If no user +records are left, the cursor ends up 'after last in tree'. */ +UNIV_INLINE +ibool +btr_pcur_move_to_next_user_rec( +/*===========================*/ + /* out: TRUE if the cursor moved forward, + ending on a user record */ + btr_pcur_t* cursor, /* in: persistent cursor; NOTE that the + function may release the page latch */ + mtr_t* mtr) /* in: mtr */ +{ + ut_ad(cursor->pos_state == BTR_PCUR_IS_POSITIONED); + ut_ad(cursor->latch_mode != BTR_NO_LATCHES); + cursor->old_stored = BTR_PCUR_OLD_NOT_STORED; +loop: + if (btr_pcur_is_after_last_on_page(cursor, mtr)) { + + if (btr_pcur_is_after_last_in_tree(cursor, mtr)) { + + return(FALSE); + } + + btr_pcur_move_to_next_page(cursor, mtr); + } else { + btr_pcur_move_to_next_on_page(cursor, mtr); + } + + if (btr_pcur_is_on_user_rec(cursor, mtr)) { + + return(TRUE); + } + + goto loop; +} + +/************************************************************* +Moves the persistent cursor to the next record in the tree. If no records are +left, the cursor stays 'after last in tree'. */ +UNIV_INLINE +ibool +btr_pcur_move_to_next( +/*==================*/ + /* out: TRUE if the cursor was not after last + in tree */ + btr_pcur_t* cursor, /* in: persistent cursor; NOTE that the + function may release the page latch */ + mtr_t* mtr) /* in: mtr */ +{ + ut_ad(cursor->pos_state == BTR_PCUR_IS_POSITIONED); + ut_ad(cursor->latch_mode != BTR_NO_LATCHES); + + cursor->old_stored = BTR_PCUR_OLD_NOT_STORED; + + if (btr_pcur_is_after_last_on_page(cursor, mtr)) { + + if (btr_pcur_is_after_last_in_tree(cursor, mtr)) { + + return(FALSE); + } + + btr_pcur_move_to_next_page(cursor, mtr); + + return(TRUE); + } + + btr_pcur_move_to_next_on_page(cursor, mtr); + + return(TRUE); +} + +/****************************************************************** +Commits the pcur mtr and sets the pcur latch mode to BTR_NO_LATCHES, +that is, the cursor becomes detached. If there have been modifications +to the page where pcur is positioned, this can be used instead of +btr_pcur_release_leaf. Function btr_pcur_store_position should be used +before calling this, if restoration of cursor is wanted later. */ +UNIV_INLINE +void +btr_pcur_commit( +/*============*/ + btr_pcur_t* pcur) /* in: persistent cursor */ +{ + ut_a(pcur->pos_state == BTR_PCUR_IS_POSITIONED); + + pcur->latch_mode = BTR_NO_LATCHES; + + mtr_commit(pcur->mtr); + + pcur->pos_state = BTR_PCUR_WAS_POSITIONED; +} + +/****************************************************************** +Differs from btr_pcur_commit in that we can specify the mtr to commit. */ +UNIV_INLINE +void +btr_pcur_commit_specify_mtr( +/*========================*/ + btr_pcur_t* pcur, /* in: persistent cursor */ + mtr_t* mtr) /* in: mtr to commit */ +{ + ut_a(pcur->pos_state == BTR_PCUR_IS_POSITIONED); + + pcur->latch_mode = BTR_NO_LATCHES; + + mtr_commit(mtr); + + pcur->pos_state = BTR_PCUR_WAS_POSITIONED; +} + +/****************************************************************** +Sets the pcur latch mode to BTR_NO_LATCHES. */ +UNIV_INLINE +void +btr_pcur_detach( +/*============*/ + btr_pcur_t* pcur) /* in: persistent cursor */ +{ + ut_a(pcur->pos_state == BTR_PCUR_IS_POSITIONED); + + pcur->latch_mode = BTR_NO_LATCHES; + + pcur->pos_state = BTR_PCUR_WAS_POSITIONED; +} + +/****************************************************************** +Tests if a cursor is detached: that is the latch mode is BTR_NO_LATCHES. */ +UNIV_INLINE +ibool +btr_pcur_is_detached( +/*=================*/ + /* out: TRUE if detached */ + btr_pcur_t* pcur) /* in: persistent cursor */ +{ + if (pcur->latch_mode == BTR_NO_LATCHES) { + + return(TRUE); + } + + return(FALSE); +} + +/****************************************************************** +Sets the old_rec_buf field to NULL. */ +UNIV_INLINE +void +btr_pcur_init( +/*==========*/ + btr_pcur_t* pcur) /* in: persistent cursor */ +{ + pcur->old_stored = BTR_PCUR_OLD_NOT_STORED; + pcur->old_rec_buf = NULL; + pcur->old_rec = NULL; +} + +/****************************************************************** +Initializes and opens a persistent cursor to an index tree. It should be +closed with btr_pcur_close. */ +UNIV_INLINE +void +btr_pcur_open( +/*==========*/ + dict_index_t* index, /* in: index */ + dtuple_t* tuple, /* in: tuple on which search done */ + ulint mode, /* in: PAGE_CUR_L, ...; + NOTE that if the search is made using a unique + prefix of a record, mode should be + PAGE_CUR_LE, not PAGE_CUR_GE, as the latter + may end up on the previous page from the + record! */ + ulint latch_mode,/* in: BTR_SEARCH_LEAF, ... */ + btr_pcur_t* cursor, /* in: memory buffer for persistent cursor */ + mtr_t* mtr) /* in: mtr */ +{ + btr_cur_t* btr_cursor; + + /* Initialize the cursor */ + + btr_pcur_init(cursor); + + cursor->latch_mode = latch_mode; + cursor->search_mode = mode; + + /* Search with the tree cursor */ + + btr_cursor = btr_pcur_get_btr_cur(cursor); + + btr_cur_search_to_nth_level(index, 0, tuple, mode, latch_mode, + btr_cursor, 0, mtr); + cursor->pos_state = BTR_PCUR_IS_POSITIONED; +} + +/****************************************************************** +Opens an persistent cursor to an index tree without initializing the +cursor. */ +UNIV_INLINE +void +btr_pcur_open_with_no_init( +/*=======================*/ + dict_index_t* index, /* in: index */ + dtuple_t* tuple, /* in: tuple on which search done */ + ulint mode, /* in: PAGE_CUR_L, ...; + NOTE that if the search is made using a unique + prefix of a record, mode should be + PAGE_CUR_LE, not PAGE_CUR_GE, as the latter + may end up on the previous page of the + record! */ + ulint latch_mode,/* in: BTR_SEARCH_LEAF, ... */ + btr_pcur_t* cursor, /* in: memory buffer for persistent cursor */ + ulint has_search_latch,/* in: latch mode the caller + currently has on btr_search_latch: + RW_S_LATCH, or 0 */ + mtr_t* mtr) /* in: mtr */ +{ + btr_cur_t* btr_cursor; + + cursor->latch_mode = latch_mode; + cursor->search_mode = mode; + + /* Search with the tree cursor */ + + btr_cursor = btr_pcur_get_btr_cur(cursor); + + btr_cur_search_to_nth_level(index, 0, tuple, mode, latch_mode, + btr_cursor, has_search_latch, mtr); + cursor->pos_state = BTR_PCUR_IS_POSITIONED; + + cursor->old_stored = BTR_PCUR_OLD_NOT_STORED; +} + +/********************************************************************* +Opens a persistent cursor at either end of an index. */ +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 */ + 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 */ +{ + pcur->latch_mode = latch_mode; + + if (from_left) { + pcur->search_mode = PAGE_CUR_G; + } else { + pcur->search_mode = PAGE_CUR_L; + } + + if (do_init) { + btr_pcur_init(pcur); + } + + btr_cur_open_at_index_side(from_left, index, latch_mode, + btr_pcur_get_btr_cur(pcur), mtr); + pcur->pos_state = BTR_PCUR_IS_POSITIONED; + + pcur->old_stored = BTR_PCUR_OLD_NOT_STORED; +} + +/************************************************************************** +Positions a cursor at a randomly chosen position within a B-tree. */ +UNIV_INLINE +void +btr_pcur_open_at_rnd_pos( +/*=====================*/ + dict_index_t* index, /* in: index */ + ulint latch_mode, /* in: BTR_SEARCH_LEAF, ... */ + btr_pcur_t* cursor, /* in/out: B-tree pcur */ + mtr_t* mtr) /* in: mtr */ +{ + /* Initialize the cursor */ + + cursor->latch_mode = latch_mode; + cursor->search_mode = PAGE_CUR_G; + + btr_pcur_init(cursor); + + btr_cur_open_at_rnd_pos(index, latch_mode, + btr_pcur_get_btr_cur(cursor), mtr); + cursor->pos_state = BTR_PCUR_IS_POSITIONED; + cursor->old_stored = BTR_PCUR_OLD_NOT_STORED; +} + +/****************************************************************** +Frees the possible memory heap of a persistent cursor and sets the latch +mode of the persistent cursor to BTR_NO_LATCHES. */ +UNIV_INLINE +void +btr_pcur_close( +/*===========*/ + btr_pcur_t* cursor) /* in: persistent cursor */ +{ + if (cursor->old_rec_buf != NULL) { + + mem_free(cursor->old_rec_buf); + + cursor->old_rec = NULL; + cursor->old_rec_buf = NULL; + } + + cursor->btr_cur.page_cur.rec = NULL; + cursor->old_rec = NULL; + cursor->old_stored = BTR_PCUR_OLD_NOT_STORED; + + cursor->latch_mode = BTR_NO_LATCHES; + cursor->pos_state = BTR_PCUR_NOT_POSITIONED; +} |