mariadb/include/trx0undo.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

330 lines
8.2 KiB
Text

/******************************************************
Transaction undo log
(c) 1996 Innobase Oy
Created 3/26/1996 Heikki Tuuri
*******************************************************/
#include "data0type.h"
/***************************************************************************
Builds a roll pointer dulint. */
UNIV_INLINE
dulint
trx_undo_build_roll_ptr(
/*====================*/
/* out: roll pointer */
ibool is_insert, /* in: TRUE if insert undo log */
ulint rseg_id, /* in: rollback segment id */
ulint page_no, /* in: page number */
ulint offset) /* in: offset of the undo entry within page */
{
#if DATA_ROLL_PTR_LEN != 7
# error "DATA_ROLL_PTR_LEN != 7"
#endif
ut_ad(rseg_id < 128);
return(ut_dulint_create(is_insert * 128 * 256 * 256
+ rseg_id * 256 * 256
+ (page_no / 256) / 256,
(page_no % (256 * 256)) * 256 * 256
+ offset));
}
/***************************************************************************
Decodes a roll pointer dulint. */
UNIV_INLINE
void
trx_undo_decode_roll_ptr(
/*=====================*/
dulint roll_ptr, /* in: roll pointer */
ibool* is_insert, /* out: TRUE if insert undo log */
ulint* rseg_id, /* out: rollback segment id */
ulint* page_no, /* out: page number */
ulint* offset) /* out: offset of the undo entry within page */
{
ulint low;
ulint high;
#if DATA_ROLL_PTR_LEN != 7
# error "DATA_ROLL_PTR_LEN != 7"
#endif
#if TRUE != 1
# error "TRUE != 1"
#endif
high = ut_dulint_get_high(roll_ptr);
low = ut_dulint_get_low(roll_ptr);
*offset = low % (256 * 256);
*is_insert = high / (256 * 256 * 128); /* TRUE == 1 */
*rseg_id = (high / (256 * 256)) % 128;
*page_no = (high % (256 * 256)) * 256 * 256
+ (low / 256) / 256;
}
/***************************************************************************
Returns TRUE if the roll pointer is of the insert type. */
UNIV_INLINE
ibool
trx_undo_roll_ptr_is_insert(
/*========================*/
/* out: TRUE if insert undo log */
dulint roll_ptr) /* in: roll pointer */
{
ulint high;
#if DATA_ROLL_PTR_LEN != 7
# error "DATA_ROLL_PTR_LEN != 7"
#endif
#if TRUE != 1
# error "TRUE != 1"
#endif
high = ut_dulint_get_high(roll_ptr);
return(high / (256 * 256 * 128));
}
/*********************************************************************
Writes a roll ptr to an index page. In case that the size changes in
some future version, this function should be used instead of
mach_write_... */
UNIV_INLINE
void
trx_write_roll_ptr(
/*===============*/
byte* ptr, /* in: pointer to memory where written */
dulint roll_ptr) /* in: roll ptr */
{
ut_ad(DATA_ROLL_PTR_LEN == 7);
mach_write_to_7(ptr, roll_ptr);
}
/*********************************************************************
Reads a roll ptr from an index page. In case that the roll ptr size
changes in some future version, this function should be used instead of
mach_read_... */
UNIV_INLINE
dulint
trx_read_roll_ptr(
/*==============*/
/* out: roll ptr */
byte* ptr) /* in: pointer to memory from where to read */
{
#if DATA_ROLL_PTR_LEN != 7
# error "DATA_ROLL_PTR_LEN != 7"
#endif
return(mach_read_from_7(ptr));
}
/**********************************************************************
Gets an undo log page and x-latches it. */
UNIV_INLINE
page_t*
trx_undo_page_get(
/*==============*/
/* out: pointer to page x-latched */
ulint space, /* in: space where placed */
ulint page_no, /* in: page number */
mtr_t* mtr) /* in: mtr */
{
page_t* page;
page = buf_page_get(space, page_no, RW_X_LATCH, mtr);
#ifdef UNIV_SYNC_DEBUG
buf_page_dbg_add_level(page, SYNC_TRX_UNDO_PAGE);
#endif /* UNIV_SYNC_DEBUG */
return(page);
}
/**********************************************************************
Gets an undo log page and s-latches it. */
UNIV_INLINE
page_t*
trx_undo_page_get_s_latched(
/*========================*/
/* out: pointer to page s-latched */
ulint space, /* in: space where placed */
ulint page_no, /* in: page number */
mtr_t* mtr) /* in: mtr */
{
page_t* page;
page = buf_page_get(space, page_no, RW_S_LATCH, mtr);
#ifdef UNIV_SYNC_DEBUG
buf_page_dbg_add_level(page, SYNC_TRX_UNDO_PAGE);
#endif /* UNIV_SYNC_DEBUG */
return(page);
}
/**********************************************************************
Returns the start offset of the undo log records of the specified undo
log on the page. */
UNIV_INLINE
ulint
trx_undo_page_get_start(
/*====================*/
/* out: start offset */
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 start;
if (page_no == buf_frame_get_page_no(undo_page)) {
start = mach_read_from_2(offset + undo_page
+ TRX_UNDO_LOG_START);
} else {
start = TRX_UNDO_PAGE_HDR + TRX_UNDO_PAGE_HDR_SIZE;
}
return(start);
}
/**********************************************************************
Returns the end offset of the undo log records of the specified undo
log on the page. */
UNIV_INLINE
ulint
trx_undo_page_get_end(
/*==================*/
/* out: end offset */
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 */
{
trx_ulogf_t* log_hdr;
ulint end;
if (page_no == buf_frame_get_page_no(undo_page)) {
log_hdr = undo_page + offset;
end = mach_read_from_2(log_hdr + TRX_UNDO_NEXT_LOG);
if (end == 0) {
end = mach_read_from_2(undo_page + TRX_UNDO_PAGE_HDR
+ TRX_UNDO_PAGE_FREE);
}
} else {
end = mach_read_from_2(undo_page + TRX_UNDO_PAGE_HDR
+ TRX_UNDO_PAGE_FREE);
}
return(end);
}
/**********************************************************************
Returns the previous undo record on the page in the specified log, or
NULL if none exists. */
UNIV_INLINE
trx_undo_rec_t*
trx_undo_page_get_prev_rec(
/*=======================*/
/* out: pointer to record, NULL if none */
trx_undo_rec_t* rec, /* in: undo log record */
ulint page_no,/* in: undo log header page number */
ulint offset) /* in: undo log header offset on page */
{
page_t* undo_page;
ulint start;
undo_page = buf_frame_align(rec);
start = trx_undo_page_get_start(undo_page, page_no, offset);
if (start + undo_page == rec) {
return(NULL);
}
return(undo_page + mach_read_from_2(rec - 2));
}
/**********************************************************************
Returns the next undo log record on the page in the specified log, or
NULL if none exists. */
UNIV_INLINE
trx_undo_rec_t*
trx_undo_page_get_next_rec(
/*=======================*/
/* out: pointer to record, NULL if none */
trx_undo_rec_t* rec, /* in: undo log record */
ulint page_no,/* in: undo log header page number */
ulint offset) /* in: undo log header offset on page */
{
page_t* undo_page;
ulint end;
ulint next;
undo_page = buf_frame_align(rec);
end = trx_undo_page_get_end(undo_page, page_no, offset);
next = mach_read_from_2(rec);
if (next == end) {
return(NULL);
}
return(undo_page + next);
}
/**********************************************************************
Returns the last undo record on the page in the specified undo log, or
NULL if none exists. */
UNIV_INLINE
trx_undo_rec_t*
trx_undo_page_get_last_rec(
/*=======================*/
/* out: pointer to record, 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 start;
ulint end;
start = trx_undo_page_get_start(undo_page, page_no, offset);
end = trx_undo_page_get_end(undo_page, page_no, offset);
if (start == end) {
return(NULL);
}
return(undo_page + mach_read_from_2(undo_page + end - 2));
}
/**********************************************************************
Returns the first undo record on the page in the specified undo log, or
NULL if none exists. */
UNIV_INLINE
trx_undo_rec_t*
trx_undo_page_get_first_rec(
/*========================*/
/* out: pointer to record, 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 start;
ulint end;
start = trx_undo_page_get_start(undo_page, page_no, offset);
end = trx_undo_page_get_end(undo_page, page_no, offset);
if (start == end) {
return(NULL);
}
return(undo_page + start);
}