/***************************************************************************
Gets the previous record in an undo log from the previous page. */
static
trx_undo_rec_t*
trx_undo_get_prev_rec_from_prev_page(
/*=================================*/
/* out: undo log record, the page s-latched,
NULL if none */
trx_undo_rec_t* rec, /* in: undo record */
ulint page_no,/* in: undo log header page number */
ulint offset, /* in: undo log header offset on page */
mtr_t* mtr) /* in: mtr */
{
ulint prev_page_no;
page_t* prev_page;
page_t* undo_page;
undo_page = buf_frame_align(rec);
prev_page_no = flst_get_prev_addr(undo_page + TRX_UNDO_PAGE_HDR
+ TRX_UNDO_PAGE_NODE, mtr)
.page;
if (prev_page_no == FIL_NULL) {
return(NULL);
}
prev_page = trx_undo_page_get_s_latched(
buf_frame_get_space_id(undo_page),
prev_page_no, mtr);
return(trx_undo_page_get_last_rec(prev_page, page_no, offset));
}
void
btr_pcur_move_to_next_page(
/*=======================*/
btr_pcur_t* cursor, /* in: persistent cursor; must be on the
last record of the current page */
mtr_t* mtr) /* in: mtr */
{
ulint next_page_no;
ulint space;
page_t* page;
page_t* next_page;
ut_a(cursor->pos_state == BTR_PCUR_IS_POSITIONED);
ut_ad(cursor->latch_mode != BTR_NO_LATCHES);
ut_ad(btr_pcur_is_after_last_on_page(cursor, mtr));
cursor->old_stored = BTR_PCUR_OLD_NOT_STORED;
page = btr_pcur_get_page(cursor);
next_page_no = btr_page_get_next(page, mtr);
space = buf_frame_get_space_id(page);
ut_ad(next_page_no != FIL_NULL);
next_page = btr_page_get(space, next_page_no, cursor->latch_mode, mtr);
ut_a(page_is_comp(next_page) == page_is_comp(page));
buf_block_align(next_page)->check_index_page_at_flush = TRUE;
btr_leaf_page_release(page, cursor->latch_mode, mtr);
page_cur_set_before_first(next_page, btr_pcur_get_page_cur(cursor));
page_check_dir(next_page);
}
/***************************************************************************
Gets the next record in an undo log from the next page. */
static
trx_undo_rec_t*
trx_undo_get_next_rec_from_next_page(
/*=================================*/
/* out: undo log record, the page latched, NULL if
none */
page_t* undo_page, /* in: undo log page */
ulint page_no,/* in: undo log header page number */
ulint offset, /* in: undo log header offset on page */
ulint mode, /* in: latch mode: RW_S_LATCH or RW_X_LATCH */
mtr_t* mtr) /* in: mtr */
{
trx_ulogf_t* log_hdr;
ulint next_page_no;
page_t* next_page;
ulint space;
ulint next;
if (page_no == buf_frame_get_page_no(undo_page)) {
log_hdr = undo_page + offset;
next = mach_read_from_2(log_hdr + TRX_UNDO_NEXT_LOG);
if (next != 0) {
return(NULL);
}
}
space = buf_frame_get_space_id(undo_page);
next_page_no = flst_get_next_addr(undo_page + TRX_UNDO_PAGE_HDR
+ TRX_UNDO_PAGE_NODE, mtr)
.page;
if (next_page_no == FIL_NULL) {
return(NULL);
}
if (mode == RW_S_LATCH) {
next_page = trx_undo_page_get_s_latched(space, next_page_no,
mtr);
} else {
ut_ad(mode == RW_X_LATCH);
next_page = trx_undo_page_get(space, next_page_no, mtr);
}
return(trx_undo_page_get_first_rec(next_page, page_no, offset));
}
void
flst_print(
/*=======*/
flst_base_node_t* base, /* in: pointer to base node of list */
mtr_t* mtr) /* in: mtr */
{
buf_frame_t* frame;
ulint len;
ut_ad(base && mtr);
ut_ad(mtr_memo_contains(mtr, buf_block_align(base),
MTR_MEMO_PAGE_X_FIX));
frame = buf_frame_align(base);
len = flst_get_len(base, mtr);
printf("FILE-BASED LIST:\n");
printf("Base node in space %lu page %lu byte offset %lu; len %lu\n",
buf_frame_get_space_id(frame), buf_frame_get_page_no(frame),
(ulint) (base - frame), len);
}
void
btr_pcur_move_backward_from_page(
/*=============================*/
btr_pcur_t* cursor, /* in: persistent cursor, must be on the first
record of the current page */
mtr_t* mtr) /* in: mtr */
{
ulint prev_page_no;
ulint space;
page_t* page;
page_t* prev_page;
ulint latch_mode;
ulint latch_mode2;
ut_a(cursor->pos_state == BTR_PCUR_IS_POSITIONED);
ut_ad(cursor->latch_mode != BTR_NO_LATCHES);
ut_ad(btr_pcur_is_before_first_on_page(cursor, mtr));
ut_ad(!btr_pcur_is_before_first_in_tree(cursor, mtr));
latch_mode = cursor->latch_mode;
if (latch_mode == BTR_SEARCH_LEAF) {
latch_mode2 = BTR_SEARCH_PREV;
} else if (latch_mode == BTR_MODIFY_LEAF) {
latch_mode2 = BTR_MODIFY_PREV;
} else {
latch_mode2 = 0; /* To eliminate compiler warning */
ut_error;
}
btr_pcur_store_position(cursor, mtr);
mtr_commit(mtr);
mtr_start(mtr);
btr_pcur_restore_position(latch_mode2, cursor, mtr);
page = btr_pcur_get_page(cursor);
prev_page_no = btr_page_get_prev(page, mtr);
space = buf_frame_get_space_id(page);
if (btr_pcur_is_before_first_on_page(cursor, mtr)
&& (prev_page_no != FIL_NULL)) {
prev_page = btr_pcur_get_btr_cur(cursor)->left_page;
btr_leaf_page_release(page, latch_mode, mtr);
page_cur_set_after_last(prev_page,
btr_pcur_get_page_cur(cursor));
} else if (prev_page_no != FIL_NULL) {
/* The repositioned cursor did not end on an infimum record on
a page. Cursor repositioning acquired a latch also on the
previous page, but we do not need the latch: release it. */
prev_page = btr_pcur_get_btr_cur(cursor)->left_page;
btr_leaf_page_release(prev_page, latch_mode, mtr);
}
cursor->latch_mode = latch_mode;
cursor->old_stored = BTR_PCUR_OLD_NOT_STORED;
}
