replication fixes

Docs/manual.texi:
  updates from Matthias Urlichs
mysql-test/r/rpl000016.result:
  position sanity check - hope to catch the timing bug
mysql-test/t/rpl000016.test:
  position sanity check - hope to catch timing bug
sql/log_event.cc:
  limit event length by max_allowed_packet
sql/log_event.h:
  abolish MAX_EVENT_LEN
sql/sql_repl.cc:
  error for events larger than max_allowed_packet

Docs/manual.texi

@@ -41585,6 +41585,9 @@ not yet 100 % confident in this code.
 @appendixsubsec Changes in release 3.23.34
 @itemize @bullet
 @item
+Limit query length for replication by max_allowed_packet, not the arbitrary
+limit of 4 MB
+@item
 Allow space around @code{=} in argument to @code{--set-variable}.
 @item
 Fixed problem in automatic repair that could let some threads in state
@@ -41606,7 +41609,7 @@ Fixed that @code{mysqlbinlog} writes the timestamp value for each query.
 This ensures that on gets same values for date functions like @code{NOW()}
 when using @code{mysqlbinlog} to pipe the queries to another server.
 @item
-Allow one to use @code{--skip-gemeni}, @code{--skip-bdb} and
+Allow one to use @code{--skip-gemini}, @code{--skip-bdb} and
 @code{--skip-innobase} to @code{mysqld} even if these databases are not
 compiled in @code{mysqld}.
 @item

mysql-test/r/rpl000016.result

@@ -21,5 +21,9 @@ Log_name
 master-bin.003
 master-bin.004
 master-bin.005
+File	Position	Binlog_do_db	Binlog_ignore_db
+master-bin.005	1504		
+Master_Host	Master_User	Master_Port	Connect_retry	Log_File	Pos	Slave_Running	Replicate_do_db	Replicate_ignore_db	Last_errno	Last_error	Skip_counter
+127.0.0.1	root	9306	60	master-bin.005	1504	Yes			0		0
 count(*)
 100

mysql-test/t/rpl000016.test

@@ -78,11 +78,13 @@ while ($1)
  dec $1;
 }
 show master logs;
+show master status;
 save_master_pos;
 connection slave;
 slave stop;
 slave start;
 sync_with_master;
+show slave status;
 select count(*) from t3 where n = 4;
 #clean up
 connection master;

sql/log_event.cc

@@ -85,10 +85,11 @@ int Log_event::read_log_event(IO_CACHE* file, String* packet,
     return file->error > 0 ? LOG_READ_TRUNC: LOG_READ_IO;
   }
   data_len = uint4korr(buf + EVENT_LEN_OFFSET);
-  if (data_len < LOG_EVENT_HEADER_LEN || data_len > MAX_EVENT_LEN)
+  if (data_len < LOG_EVENT_HEADER_LEN || data_len > max_allowed_packet)
   {
     if (log_lock) pthread_mutex_unlock(log_lock);
-    return LOG_READ_BOGUS;
+    return (data_len < LOG_EVENT_HEADER_LEN) ? LOG_READ_BOGUS :
+      LOG_READ_TOO_LARGE;
   }
   packet->append(buf, sizeof(buf));
   data_len -= LOG_EVENT_HEADER_LEN;

sql/log_event.h

@@ -31,6 +31,7 @@
 #define LOG_READ_IO     -3
 #define LOG_READ_MEM    -5
 #define LOG_READ_TRUNC  -6
+#define LOG_READ_TOO_LARGE -7
 
 #define LOG_EVENT_OFFSET 4
 #define BINLOG_VERSION    1
@@ -42,7 +43,6 @@
   + sizeof(uint32) + 2 + sizeof(uint32))
 #define EVENT_LEN_OFFSET     9
 #define EVENT_TYPE_OFFSET    4
-#define MAX_EVENT_LEN        4*1024*1024 
 #define QUERY_EVENT_OVERHEAD  (LOG_EVENT_HEADER_LEN+QUERY_HEADER_LEN)
 #define ROTATE_EVENT_OVERHEAD LOG_EVENT_HEADER_LEN
 #define LOAD_EVENT_OVERHEAD   (LOG_EVENT_HEADER_LEN+LOAD_HEADER_LEN+sizeof(sql_ex_info))

sql/sql_repl.cc

@@ -352,6 +352,10 @@ sweepstakes if you report the bug";
       case LOG_READ_BOGUS: 
 	errmsg = "bogus data in log event";
 	break;
+      case LOG_READ_TOO_LARGE: 
+	errmsg = "log event entry exceeded max_allowed_packet -\
+ increase max_allowed_packet on master";
+	break;
       case LOG_READ_IO:
 	errmsg = "I/O error reading log event";
 	break;