mariadb/include/btr0pcur.ic
marko 8f18616ef0 Reindent the code base (except for ha_innodb.{cc,h} and generated parser
and lexer files).  From now on, the following Emacs cc-mode settings apply
when indenting C function bodies in InnoDB:

(setq c-basic-offset 8)
(setq c-label-minimum-indentation 0)
(add-to-list 'c-offsets-alist '(c . 0))
(add-to-list 'c-offsets-alist '(label . [0]))

The indentation rules for function declarations still have not been
formalized, and they must be formatted manually.

Try to limit all lines to at most 79 characters (assuming TAB stops every
8 characters) by splitting lines before opening parenthesis, or at
string constants.

Fix some grammar mistakes in diagnostic output:
 match to, match with -> match
 found from -> found in
 trying rename -> trying to rename

Fix an error in page_check_dir(): it said "supremum not pointed to"
when the infimum was not pointed to.

Enclose commented-out code snippets in #if 0 ... #endif instead of /* ... */.
Add (void*) casts to some %p parameters in fprintf() calls.  Try to
split lines before a binary operator, not after one.  (These three fixes
were not made everywhere.)
2006-08-28 17:42:45 +00:00

630 lines
16 KiB
Text

/******************************************************
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 last record on the same page. */
UNIV_INLINE
void
btr_pcur_move_to_last_on_page(
/*==========================*/
btr_pcur_t* cursor, /* in: persistent cursor */
mtr_t* mtr) /* in: mtr */
{
UT_NOT_USED(mtr);
ut_ad(cursor->latch_mode != BTR_NO_LATCHES);
page_cur_set_after_last(buf_frame_align(btr_pcur_get_rec(cursor)),
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;
cursor->trx_if_known = NULL;
}
/******************************************************************
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, ...;
NOTE that if has_search_latch != 0 then
we maybe do not acquire a latch on the cursor
page, but assume that the caller uses his
btr search latch to protect the record! */
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;
cursor->trx_if_known = NULL;
}
/*********************************************************************
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;
pcur->trx_if_known = NULL;
}
/**************************************************************************
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;
cursor->trx_if_known = NULL;
}
/******************************************************************
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;
cursor->trx_if_known = NULL;
}