mariadb/storage/maria/ma_loghandler_lsn.h
unknown fdf847fb62 comments fixed
storage/maria/ma_loghandler.c:
  The function comment fixed.
storage/maria/ma_loghandler_lsn.h:
  Comment of LSN/TRANSLOG_ADDRESS type fixed
2007-02-27 10:59:01 +02:00

56 lines
1.5 KiB
C

#ifndef _ma_loghandler_lsn_h
#define _ma_loghandler_lsn_h
/*
Transaction log record address:
file_no << 32 | offset
file_no is only 3 bytes so we can use signed integer to make
comparison more simple.
*/
typedef int64 TRANSLOG_ADDRESS;
/*
Compare addresses
A1 > A2 -> result > 0
A1 == A2 -> 0
A1 < A2 -> result < 0
*/
#define cmp_translog_addr(A1,A2) ((A1) - (A2))
/* LSN type (address of certain log record chank */
typedef TRANSLOG_ADDRESS LSN;
/* Gets file number part of a LSN/log address */
#define LSN_FILE_NO(L) ((L) >> 32)
/* Gets raw file number part of a LSN/log address */
#define LSN_FINE_NO_PART(L) ((L) & ((int64)0xFFFFFF00000000LL))
/* Gets record offset of a LSN/log address */
#define LSN_OFFSET(L) ((L) & 0xFFFFFFFFL)
/* Makes lsn/log address from file number and record offset */
#define MAKE_LSN(F,S) ((((uint64)(F)) << 32) | (S))
/* checks LSN */
#define LSN_VALID(L) DBUG_ASSERT((L) >= 0 && (L) < (uint64)0xFFFFFFFFFFFFFFLL)
/* size of stored LSN on a disk */
#define LSN_STORE_SIZE 7
/* Puts LSN into buffer (dst) */
#define lsn_store(dst, lsn) \
do { \
int3store((dst), LSN_FILE_NO(lsn)); \
int4store((dst) + 3, LSN_OFFSET(lsn)); \
} while (0)
/* Unpacks LSN from the buffer (P) */
#define lsn_korr(P) MAKE_LSN(uint3korr(P), uint4korr((P) + 3))
/* what we need to add to LSN to increase it on one file */
#define LSN_ONE_FILE ((int64)0x100000000LL)
#define LSN_REPLACE_OFFSET(L, S) (LSN_FINE_NO_PART(L) | (S))
#endif