trx0rseg.ic
上传用户:tsgydb
上传日期:2007-04-14
资源大小:10674k
文件大小:3k
- /******************************************************
- Rollback segment
- (c) 1996 Innobase Oy
- Created 3/26/1996 Heikki Tuuri
- *******************************************************/
- #include "srv0srv.h"
- /**********************************************************************
- Gets a rollback segment header. */
- UNIV_INLINE
- trx_rsegf_t*
- trx_rsegf_get(
- /*==========*/
- /* out: rollback segment header, page
- x-latched */
- ulint space, /* in: space where placed */
- ulint page_no, /* in: page number of the header */
- mtr_t* mtr) /* in: mtr */
- {
- trx_rsegf_t* header;
- header = TRX_RSEG + buf_page_get(space, page_no, RW_X_LATCH, mtr);
- buf_page_dbg_add_level(header, SYNC_RSEG_HEADER);
- return(header);
- }
- /**********************************************************************
- Gets a newly created rollback segment header. */
- UNIV_INLINE
- trx_rsegf_t*
- trx_rsegf_get_new(
- /*==============*/
- /* out: rollback segment header, page
- x-latched */
- ulint space, /* in: space where placed */
- ulint page_no, /* in: page number of the header */
- mtr_t* mtr) /* in: mtr */
- {
- trx_rsegf_t* header;
- header = TRX_RSEG + buf_page_get(space, page_no, RW_X_LATCH, mtr);
- buf_page_dbg_add_level(header, SYNC_RSEG_HEADER_NEW);
- return(header);
- }
- /*******************************************************************
- Gets the file page number of the nth undo log slot. */
- UNIV_INLINE
- ulint
- trx_rsegf_get_nth_undo(
- /*===================*/
- /* out: page number of the undo log segment */
- trx_rsegf_t* rsegf, /* in: rollback segment header */
- ulint n, /* in: index of slot */
- mtr_t* mtr) /* in: mtr */
- {
- ut_ad(n < TRX_RSEG_N_SLOTS);
- return(mtr_read_ulint(rsegf + TRX_RSEG_UNDO_SLOTS +
- n * TRX_RSEG_SLOT_SIZE, MLOG_4BYTES, mtr));
- }
- /*******************************************************************
- Sets the file page number of the nth undo log slot. */
- UNIV_INLINE
- void
- trx_rsegf_set_nth_undo(
- /*===================*/
- trx_rsegf_t* rsegf, /* in: rollback segment header */
- ulint n, /* in: index of slot */
- ulint page_no,/* in: page number of the undo log segment */
- mtr_t* mtr) /* in: mtr */
- {
- ut_ad(n < TRX_RSEG_N_SLOTS);
- mlog_write_ulint(rsegf + TRX_RSEG_UNDO_SLOTS + n * TRX_RSEG_SLOT_SIZE,
- page_no, MLOG_4BYTES, mtr);
- }
- /********************************************************************
- Looks for a free slot for an undo log segment. */
- UNIV_INLINE
- ulint
- trx_rsegf_undo_find_free(
- /*=====================*/
- /* out: slot index or ULINT_UNDEFINED if not
- found */
- trx_rsegf_t* rsegf, /* in: rollback segment header */
- mtr_t* mtr) /* in: mtr */
- {
- ulint i;
- ulint page_no;
-
- for (i = 0; i < TRX_RSEG_N_SLOTS; i++) {
- page_no = trx_rsegf_get_nth_undo(rsegf, i, mtr);
- if (page_no == FIL_NULL) {
- return(i);
- }
- }
- return(ULINT_UNDEFINED);
- }