Merge with 3.23 to get bug fix for SHOW PROCESSLIST + running thread

sql/slave.cc

@@ -867,6 +867,7 @@ static int create_table_from_dump(THD* thd, NET* net, const char* db,
 				  const char* table_name)
 {
   ulong packet_len = my_net_read(net); // read create table statement
+  char *query;
   Vio* save_vio;
   HA_CHECK_OPT check_opt;
   TABLE_LIST tables;
@@ -886,15 +887,23 @@ static int create_table_from_dump(THD* thd, NET* net, const char* db,
     return 1;
   }
   thd->command = COM_TABLE_DUMP;
-  thd->query = sql_alloc(packet_len + 1);
-  if (!thd->query)
+  /* Note that we should not set thd->query until the area is initalized */
+  if (!(query = sql_alloc(packet_len + 1)))
   {
     sql_print_error("create_table_from_dump: out of memory");
     net_printf(&thd->net, ER_GET_ERRNO, "Out of memory");
     return 1;
   }
-  memcpy(thd->query, net->read_pos, packet_len);
-  thd->query[packet_len] = 0;
+  memcpy(query, net->read_pos, packet_len);
+  query[packet_len]= 0;
+  thd->query_length= packet_len;
+  /*
+    We make the following lock in an attempt to ensure that the compiler will
+    not rearrange the code so that thd->query is set too soon
+  */
+  VOID(pthread_mutex_lock(&LOCK_thread_count));
+  thd->query= query;
+  VOID(pthread_mutex_unlock(&LOCK_thread_count));
   thd->current_tablenr = 0;
   thd->query_error = 0;
   thd->net.no_send_ok = 1;
@@ -2049,7 +2058,9 @@ err:
   // print the current replication position
   sql_print_error("Slave I/O thread exiting, read up to log '%s', position %s",
 		  IO_RPL_LOG_NAME, llstr(mi->master_log_pos,llbuff));
+  VOID(pthread_mutex_lock(&LOCK_thread_count));
   thd->query = thd->db = 0; // extra safety
+  VOID(pthread_mutex_unlock(&LOCK_thread_count));
   if (mysql)
   {
     mc_mysql_close(mysql);
@@ -2183,7 +2194,9 @@ the slave SQL thread with \"SLAVE START\". We stopped at log \
 		  RPL_LOG_NAME, llstr(rli->master_log_pos,llbuff));
 
  err:
+  VOID(pthread_mutex_lock(&LOCK_thread_count));
   thd->query = thd->db = 0; // extra safety
+  VOID(pthread_mutex_unlock(&LOCK_thread_count));
   thd->proc_info = "Waiting for slave mutex on exit";
   pthread_mutex_lock(&rli->run_lock);
   DBUG_ASSERT(rli->slave_running == 1); // tracking buffer overrun

sql/sql_db.cc

@@ -78,9 +78,9 @@ int mysql_create_db(THD *thd, char *db, uint create_options, bool silent)
     if (!thd->query)
     {
       /* The client used the old obsolete mysql_create_db() call */
-      thd->query = path;
       thd->query_length = (uint) (strxmov(path,"create database `", db, "`",
 					  NullS) - path);
+      thd->query = path;
     }
     {
       mysql_update_log.write(thd,thd->query, thd->query_length);
@@ -92,8 +92,9 @@ int mysql_create_db(THD *thd, char *db, uint create_options, bool silent)
     }
     if (thd->query == path)
     {
+      VOID(pthread_mutex_lock(&LOCK_thread_count));
       thd->query = 0; // just in case
-      thd->query_length = 0;
+      VOID(pthread_mutex_unlock(&LOCK_thread_count));
     }
     send_ok(&thd->net, result);
   }
@@ -167,9 +168,10 @@ int mysql_rm_db(THD *thd,char *db,bool if_exists, bool silent)
     {
       if (!thd->query)
       {
-	thd->query = path;
-	thd->query_length = (uint) (strxmov(path,"drop database ", db, NullS)-
-				    path);
+	thd->query_length= (uint) (strxmov(path,"drop database `", db, "`",
+					   NullS)-
+				   path);
+	thd->query= path;
       }
       mysql_update_log.write(thd, thd->query, thd->query_length);
       if (mysql_bin_log.is_open())
@@ -179,8 +181,9 @@ int mysql_rm_db(THD *thd,char *db,bool if_exists, bool silent)
       }
       if (thd->query == path)
       {
+	VOID(pthread_mutex_lock(&LOCK_thread_count));
 	thd->query = 0; // just in case
-	thd->query_length = 0;
+	VOID(pthread_mutex_unlock(&LOCK_thread_count));
       }
       send_ok(&thd->net,(ulong) deleted);
     }

sql/sql_parse.cc

@@ -852,7 +852,7 @@ int mysql_table_dump(THD* thd, char* db, char* tbl_name, int fd)
     goto err;
   }
   net_flush(&thd->net);
-  if ((error = table->file->dump(thd,fd)))
+  if ((error= table->file->dump(thd,fd)))
     my_error(ER_GET_ERRNO, MYF(0));
 
 err:
@@ -958,7 +958,6 @@ bool dispatch_command(enum enum_server_command command, THD *thd,
       tbl_name[tbl_len] = 0;
       if (mysql_table_dump(thd, db, tbl_name, -1))
 	send_error(&thd->net); // dump to NET
-
       break;
     }
   case COM_CHANGE_USER: