Robustness feature.

Won't be pushed as is - separate email sent for internal review.
WL#1717 "binlog-innodb consistency".
Now when mysqld starts, if InnoDB does a crash recovery, we use the binlog name
and position retrieved from InnoDB (corresponding to the last transaction
successfully committed by InnoDB) to cut any rolled back transaction from
the binary log. This is triggered by the --innodb-safe-binlog option.
Provided you configure mysqld to fsync() InnoDB at every commit (using
flush_log_at_trx_commit) and to fsync() the binlog at every write
(using --sync-binlog=1), this behaviour guarantees that a master always has
consistency between binlog and InnoDB, whenever the crash happens.
6 tests to verify that it works.

1 files changed, 28 insertions, 10 deletions

diff --git a/innobase/trx/trx0sys.c b/innobase/trx/trx0sys.c
index b377bdb9809..a0dfdb51259 100644
--- a/innobase/trx/trx0sys.c
+++ b/innobase/trx/trx0sys.c
@@ -45,6 +45,15 @@ or there was no master log position info inside InnoDB. */
 char 		trx_sys_mysql_master_log_name[TRX_SYS_MYSQL_LOG_NAME_LEN];
 ib_longlong	trx_sys_mysql_master_log_pos	= -1;
 
+/* If this MySQL server uses binary logging, after InnoDB has been inited
+and if it has done a crash recovery, we store the binlog file name and position
+here. If .._pos is -1, it means there was no binlog position info inside
+InnoDB. */
+
+char 		trx_sys_mysql_bin_log_name[TRX_SYS_MYSQL_LOG_NAME_LEN];
+ib_longlong	trx_sys_mysql_bin_log_pos	= -1;
+
+
 /********************************************************************
 Determines if a page number is located inside the doublewrite buffer. */
 
@@ -650,8 +659,8 @@ trx_sys_print_mysql_binlog_offset_from_page(
 #endif /* UNIV_HOTBACKUP */
 
 /*********************************************************************
-Prints to stderr the MySQL binlog offset info in the trx system header if
-the magic number shows it valid. */
+Stores the MySQL binlog offset info in the trx system header if
+the magic number shows it valid, and print the info to stderr */
 
 void
 trx_sys_print_mysql_binlog_offset(void)
@@ -659,7 +668,8 @@ trx_sys_print_mysql_binlog_offset(void)
 {
 	trx_sysf_t*	sys_header;
 	mtr_t		mtr;
-	
+	ulong           trx_sys_mysql_bin_log_pos_high, trx_sys_mysql_bin_log_pos_low;
+
 	mtr_start(&mtr);
 
 	sys_header = trx_sysf_get(&mtr);
@@ -673,14 +683,22 @@ trx_sys_print_mysql_binlog_offset(void)
 		return;
 	}
 
-	fprintf(stderr,
-	"InnoDB: Last MySQL binlog file position %lu %lu, file name %s\n",
-		(ulong) mach_read_from_4(sys_header + TRX_SYS_MYSQL_LOG_INFO
-					+ TRX_SYS_MYSQL_LOG_OFFSET_HIGH),
-		(ulong) mach_read_from_4(sys_header + TRX_SYS_MYSQL_LOG_INFO
-					+ TRX_SYS_MYSQL_LOG_OFFSET_LOW),
-		sys_header + TRX_SYS_MYSQL_LOG_INFO + TRX_SYS_MYSQL_LOG_NAME);
+        trx_sys_mysql_bin_log_pos_high = mach_read_from_4(sys_header + TRX_SYS_MYSQL_LOG_INFO
+                                                    + TRX_SYS_MYSQL_LOG_OFFSET_HIGH);
+        trx_sys_mysql_bin_log_pos_low  = mach_read_from_4(sys_header + TRX_SYS_MYSQL_LOG_INFO
+                                                    + TRX_SYS_MYSQL_LOG_OFFSET_LOW);
+
+        trx_sys_mysql_bin_log_pos      =  (((ib_longlong)trx_sys_mysql_bin_log_pos_high) << 32) +
+          (ib_longlong)trx_sys_mysql_bin_log_pos_low;
+
+        ut_memcpy(trx_sys_mysql_bin_log_name, sys_header + TRX_SYS_MYSQL_LOG_INFO +
+                  TRX_SYS_MYSQL_LOG_NAME, TRX_SYS_MYSQL_LOG_NAME_LEN);
 
+        fprintf(stderr,
+                "InnoDB: Last MySQL binlog file position %lu %lu, file name %s\n",
+                trx_sys_mysql_bin_log_pos_high, trx_sys_mysql_bin_log_pos_low,
+                trx_sys_mysql_bin_log_name);
+        
 	mtr_commit(&mtr);
 }