Bug#12713 "Error in a stored function called from a SELECT doesn't

cause ROLLBACK of statement", part 1. Review fixes.

Do not send OK/EOF packets to the client until we reached the end of 
the current statement.
This is a consolidation, to keep the functionality that is shared by all 
SQL statements in one place in the server.
Currently this functionality includes:
- close_thread_tables()
- log_slow_statement().

After this patch and the subsequent patch for Bug#12713, it shall also include:
- ha_autocommit_or_rollback()
- net_end_statement()
- query_cache_end_of_result().

In future it may also include:
- mysql_reset_thd_for_next_command().

include/mysql_com.h

@@ -203,14 +203,10 @@ typedef struct st_net {
   unsigned int *return_status;
   unsigned char reading_or_writing;
   char save_char;
-  my_bool no_send_ok;  /* For SPs and other things that do multiple stmts */
+  my_bool unused0; /* Please remove with the next incompatible ABI change. */
   my_bool unused; /* Please remove with the next incompatible ABI change */
   my_bool compress;
-  /*
+  my_bool unused1; /* Please remove with the next incompatible ABI change. */
-    Set if OK packet is already sent, and we do not need to send error
-    messages
-  */
-  my_bool no_send_error;
   /*
     Pointer to query object in query cache, do not equal NULL (0) for
     queries in cache that have not stored its results yet
@@ -221,11 +217,14 @@ typedef struct st_net {
     functions and methods to maintain proper locking.
   */
   unsigned char *query_cache_query;
-  unsigned int last_errno;
+  unsigned int client_last_errno;
   unsigned char error; 
-  my_bool report_error; /* We should report error (we have unreported error) */
+  my_bool unused2; /* Please remove with the next incompatible ABI change. */
   my_bool return_errno;
-  char last_error[MYSQL_ERRMSG_SIZE], sqlstate[SQLSTATE_LENGTH+1];
+  /** Client library error message buffer. Actually belongs to struct MYSQL. */
+  char client_last_error[MYSQL_ERRMSG_SIZE];
+  /** Client library sqlstate buffer. Set along with the error message. */
+  char sqlstate[SQLSTATE_LENGTH+1];
   void *extension;
 } NET;
 

include/mysql_h.ic

@@ -537,16 +537,16 @@ struct __attribute__((aligned(__alignof__(void *)), aligned(__alignof__(unsigned
     unsigned int * return_status;
     unsigned char reading_or_writing;
     char save_char;
-    my_bool no_send_ok;
+    my_bool unused0;
     my_bool unused;
     my_bool compress;
-    my_bool no_send_error;
+    my_bool unused1;
     unsigned char * query_cache_query;
-    unsigned int last_errno;
+    unsigned int client_last_errno;
     unsigned char error;
-    my_bool report_error;
+    my_bool unused2;
     my_bool return_errno;
-    char last_error[512];
+    char client_last_error[512];
     char sqlstate[(5 + 1)];
     void * extension;
   };

libmysql/libmysql.c

@@ -440,11 +440,11 @@ static void expand_error(MYSQL* mysql, int error)
   char tmp[MYSQL_ERRMSG_SIZE];
   char *p;
   uint err_length;
-  strmake(tmp, mysql->net.last_error, MYSQL_ERRMSG_SIZE-1);
+  strmake(tmp, mysql->net.client_last_error, MYSQL_ERRMSG_SIZE-1);
-  p = strmake(mysql->net.last_error, ER(error), MYSQL_ERRMSG_SIZE-1);
+  p = strmake(mysql->net.client_last_error, ER(error), MYSQL_ERRMSG_SIZE-1);
-  err_length= (uint) (p - mysql->net.last_error);
+  err_length= (uint) (p - mysql->net.client_last_error);
   strmake(p, tmp, MYSQL_ERRMSG_SIZE-1 - err_length);
-  mysql->net.last_errno = error;
+  mysql->net.client_last_errno = error;
 }
 
 /*
@@ -870,9 +870,10 @@ my_bool handle_local_infile(MYSQL *mysql, const char *net_filename)
     VOID(my_net_write(net,(const uchar*) "",0)); /* Server needs one packet */
     net_flush(net);
     strmov(net->sqlstate, unknown_sqlstate);
-    net->last_errno= (*options->local_infile_error)(li_ptr,
+    net->client_last_errno=
-						    net->last_error,
+      (*options->local_infile_error)(li_ptr,
-						    sizeof(net->last_error)-1);
+                                     net->client_last_error,
+                                     sizeof(net->client_last_error)-1);
     goto err;
   }
 
@@ -899,9 +900,10 @@ my_bool handle_local_infile(MYSQL *mysql, const char *net_filename)
 
   if (readcount < 0)
   {
-    net->last_errno= (*options->local_infile_error)(li_ptr,
+    net->client_last_errno=
-						    net->last_error,
+      (*options->local_infile_error)(li_ptr,
-						    sizeof(net->last_error)-1);
+                                     net->client_last_error,
+                                     sizeof(net->client_last_error)-1);
     goto err;
   }
 
@@ -1395,7 +1397,7 @@ const char *cli_read_statistics(MYSQL *mysql)
   if (!mysql->net.read_pos[0])
   {
     set_mysql_error(mysql, CR_WRONG_HOST_INFO, unknown_sqlstate);
-    return mysql->net.last_error;
+    return mysql->net.client_last_error;
   }
   return (char*) mysql->net.read_pos;
 }
@@ -1406,7 +1408,7 @@ mysql_stat(MYSQL *mysql)
 {
   DBUG_ENTER("mysql_stat");
   if (simple_command(mysql,COM_STATISTICS,0,0,0))
-    DBUG_RETURN(mysql->net.last_error);
+    DBUG_RETURN(mysql->net.client_last_error);
   DBUG_RETURN((*mysql->methods->read_statistics)(mysql));
 }
 
@@ -1771,7 +1773,7 @@ static my_bool my_realloc_str(NET *net, ulong length)
     if (res)
     {
       strmov(net->sqlstate, unknown_sqlstate);
-      strmov(net->last_error, ER(net->last_errno));
+      strmov(net->client_last_error, ER(net->client_last_errno));
     }
     net->write_pos= net->buff+ buf_length;
   }
@@ -1822,13 +1824,15 @@ void set_stmt_error(MYSQL_STMT * stmt, int errcode,
 void set_stmt_errmsg(MYSQL_STMT *stmt, NET *net)
 {
   DBUG_ENTER("set_stmt_errmsg");
-  DBUG_PRINT("enter", ("error: %d/%s '%s'", net->last_errno, net->sqlstate,
+  DBUG_PRINT("enter", ("error: %d/%s '%s'",
-                       net->last_error));
+                       net->client_last_errno,
+                       net->sqlstate,
+                       net->client_last_error));
   DBUG_ASSERT(stmt != 0);
 
-  stmt->last_errno= net->last_errno;
+  stmt->last_errno= net->client_last_errno;
-  if (net->last_error && net->last_error[0])
+  if (net->client_last_error && net->client_last_error[0])
-    strmov(stmt->last_error, net->last_error);
+    strmov(stmt->last_error, net->client_last_error);
   strmov(stmt->sqlstate, net->sqlstate);
 
   DBUG_VOID_RETURN;

libmysql/manager.c

@@ -160,7 +160,7 @@ MYSQL_MANAGER*  STDCALL mysql_manager_connect(MYSQL_MANAGER* con,
   msg_len=strlen(msg_buf);
   if (my_net_write(&con->net,(uchar*) msg_buf,msg_len) || net_flush(&con->net))
   {
-    con->last_errno=con->net.last_errno;
+    con->last_errno=con->net.client_last_errno;
     strmov(con->last_error,"Write error on socket");
     goto err;
   }

libmysqld/lib_sql.cc

@@ -61,8 +61,8 @@ void embedded_get_error(MYSQL *mysql, MYSQL_DATA *data)
 {
   NET *net= &mysql->net;
   struct embedded_query_result *ei= data->embedded_info;
-  net->last_errno= ei->last_errno;
+  net->client_last_errno= ei->last_errno;
-  strmake(net->last_error, ei->info, sizeof(net->last_error));
+  strmake(net->client_last_error, ei->info, sizeof(net->client_last_error)-1);
   memcpy(net->sqlstate, ei->sqlstate, sizeof(net->sqlstate));
   my_free(data, MYF(0));
 }
@@ -110,12 +110,11 @@ emb_advanced_command(MYSQL *mysql, enum enum_server_command command,
     arg_length= header_length;
   }
 
-  thd->net.no_send_error= 0;
   result= dispatch_command(command, thd, (char *) arg, arg_length);
   thd->cur_data= 0;
 
   if (!skip_check)
-    result= thd->net.last_errno ? -1 : 0;
+    result= thd->is_error() ? -1 : 0;
 
   return result;
 }
@@ -370,7 +369,7 @@ static void emb_free_embedded_thd(MYSQL *mysql)
 static const char * emb_read_statistics(MYSQL *mysql)
 {
   THD *thd= (THD*)mysql->thd;
-  return thd->net.last_error;
+  return thd->is_error() ? thd->main_da.message() : "";
 }
 
 
@@ -675,8 +674,10 @@ int check_embedded_connection(MYSQL *mysql, const char *db)
 err:
   {
     NET *net= &mysql->net;
-    memcpy(net->last_error, thd->net.last_error, sizeof(net->last_error));
+    strmake(net->client_last_error, thd->main_da.message(), sizeof(net->client_last_error)-1);
-    memcpy(net->sqlstate, thd->net.sqlstate, sizeof(net->sqlstate));
+    memcpy(net->sqlstate,
+           mysql_errno_to_sqlstate(thd->main_da.sql_errno()),
+           sizeof(net->sqlstate)-1);
   }
   return result;
 }
@@ -699,9 +700,8 @@ void THD::clear_data_list()
 
 void THD::clear_error()
 {
-  net.last_error[0]= 0;
+  if (main_da.is_error())
-  net.last_errno= 0;
+    main_da.reset_diagnostics_area();
-  net.report_error= 0;
 }
 
 static char *dup_str_aux(MEM_ROOT *root, const char *from, uint length,
@@ -764,20 +764,18 @@ MYSQL_DATA *THD::alloc_new_dataset()
 }
 
 
-/*
+/**
-  stores server_status and warning_count in the current
+  Stores server_status and warning_count in the current
-  query result structures
+  query result structures.
 
-  SYNOPSIS
+  @param thd            current thread
-  write_eof_packet()
-  thd		current thread
-
-  NOTES
-    should be called to after we get the recordset-result
 
+  @note Should be called after we get the recordset-result.
 */
 
-static void write_eof_packet(THD *thd)
+static
+void
+write_eof_packet(THD *thd, uint server_status, uint total_warn_count)
 {
   if (!thd->mysql)            // bootstrap file handling
     return;
@@ -788,13 +786,13 @@ static void write_eof_packet(THD *thd)
   */
   if (thd->is_fatal_error)
     thd->server_status&= ~SERVER_MORE_RESULTS_EXISTS;
-  thd->cur_data->embedded_info->server_status= thd->server_status;
+  thd->cur_data->embedded_info->server_status= server_status;
   /*
     Don't send warn count during SP execution, as the warn_list
     is cleared between substatements, and mysqltest gets confused
   */
   thd->cur_data->embedded_info->warning_count=
-    (thd->spcont ? 0 : min(thd->total_warn_count, 65535));
+    (thd->spcont ? 0 : min(total_warn_count, 65535));
 }
 
 
@@ -950,7 +948,7 @@ bool Protocol::send_fields(List<Item> *list, uint flags)
   }
 
   if (flags & SEND_EOF)
-    write_eof_packet(thd);
+    write_eof_packet(thd, thd->server_status, thd->total_warn_count);
 
   DBUG_RETURN(prepare_for_send(list));
  err:
@@ -990,17 +988,35 @@ bool Protocol_binary::write()
   return false;
 }
 
+
+/**
+  Embedded library implementation of OK response.
+
+  This function is used by the server to write 'OK' packet to
+  the "network" when the server is compiled as an embedded library.
+  Since there is no network in the embedded configuration,
+  a different implementation is necessary.
+  Instead of marshalling response parameters to a network representation
+  and then writing it to the socket, here we simply copy the data to the
+  corresponding client-side connection structures. 
+
+  @sa Server implementation of net_send_ok in protocol.cc for
+  description of the arguments.
+
+  @return The function does not return errors.
+*/
+
 void
-send_ok(THD *thd,ha_rows affected_rows,ulonglong id,const char *message)
+net_send_ok(THD *thd,
+            uint server_status, uint total_warn_count,
+            ha_rows affected_rows, ulonglong id, const char *message)
 {
-  DBUG_ENTER("send_ok");
+  DBUG_ENTER("emb_net_send_ok");
   MYSQL_DATA *data;
   MYSQL *mysql= thd->mysql;
 
   if (!mysql)            // bootstrap file handling
     DBUG_VOID_RETURN;
-  if (thd->net.no_send_ok)	// hack for re-parsing queries
-    DBUG_VOID_RETURN;
   if (!(data= thd->alloc_new_dataset()))
     return;
   data->embedded_info->affected_rows= affected_rows;
@@ -1009,15 +1025,24 @@ send_ok(THD *thd,ha_rows affected_rows,ulonglong id,const char *message)
     strmake(data->embedded_info->info, message,
             sizeof(data->embedded_info->info)-1);
 
-  write_eof_packet(thd);
+  write_eof_packet(thd, server_status, total_warn_count);
   thd->cur_data= 0;
   DBUG_VOID_RETURN;
 }
 
+
+/**
+  Embedded library implementation of EOF response.
+
+  @sa net_send_ok
+
+  @return This function does not return errors.
+*/
+
 void
-send_eof(THD *thd)
+net_send_eof(THD *thd, uint server_status, uint total_warn_count)
 {
-  write_eof_packet(thd);
+  write_eof_packet(thd, server_status, total_warn_count);
   thd->cur_data= 0;
 }
 

libmysqld/libmysqld.c

@@ -209,8 +209,9 @@ mysql_real_connect(MYSQL *mysql,const char *host, const char *user,
   DBUG_RETURN(mysql);
 
 error:
-  DBUG_PRINT("error",("message: %u (%s)", mysql->net.last_errno,
+  DBUG_PRINT("error",("message: %u (%s)",
-		      mysql->net.last_error));
+                      mysql->net.client_last_errno,
+                      mysql->net.client_last_error));
   {
     /* Free alloced memory */
     my_bool free_me=mysql->free_me;

mysql-test/r/events.result

@@ -403,9 +403,10 @@ ERROR 42S02: Table 'mysql.event' doesn't exist
 DROP DATABASE IF EXISTS mysqltest_no_such_database;
 Warnings:
 Note	1008	Can't drop database 'mysqltest_no_such_database'; database doesn't exist
-Error	1146	Table 'mysql.event' doesn't exist
 CREATE DATABASE mysqltest_db2;
 DROP DATABASE mysqltest_db2;
+Warnings:
+Error	1146	Table 'mysql.event' doesn't exist
 OK, there is an unnecessary warning about the non-existent table 
 but it's not easy to fix and no one complained about it.
 A similar warning is printed if mysql.proc is missing.

mysql-test/r/grant.result

@@ -1229,9 +1229,7 @@ set names default;
 FLUSH PRIVILEGES without procs_priv table.
 RENAME TABLE mysql.procs_priv TO mysql.procs_gone;
 FLUSH PRIVILEGES;
-Warnings:
+ERROR 42S02: Table 'mysql.procs_priv' doesn't exist
-Error	1146	Table 'mysql.procs_priv' doesn't exist
-Error	1548	Cannot load from mysql.mysql.procs_priv. The table is probably corrupted
 Assigning privileges without procs_priv table.
 CREATE DATABASE mysqltest1;
 CREATE PROCEDURE mysqltest1.test() SQL SECURITY DEFINER

mysql-test/suite/rpl/r/rpl_row_tabledefs_2myisam.result

@@ -123,7 +123,7 @@ Replicate_Ignore_Table
 Replicate_Wild_Do_Table	
 Replicate_Wild_Ignore_Table	
 Last_Errno	1364
-Last_Error	Error in Write_rows event: error during transaction execution on table test.t1_nodef. 
+Last_Error	Error in Write_rows event: error during transaction execution on table test.t1_nodef. Field 'x' doesn't have a default value
 Skip_Counter	0
 Exec_Master_Log_Pos	#
 Relay_Log_Space	#
@@ -141,7 +141,7 @@ Master_SSL_Verify_Server_Cert	No
 Last_IO_Errno	0
 Last_IO_Error	
 Last_SQL_Errno	1364
-Last_SQL_Error	Error in Write_rows event: error during transaction execution on table test.t1_nodef. 
+Last_SQL_Error	Error in Write_rows event: error during transaction execution on table test.t1_nodef. Field 'x' doesn't have a default value
 SET GLOBAL SQL_SLAVE_SKIP_COUNTER=2;
 START SLAVE;
 INSERT INTO t9 VALUES (2);

mysql-test/suite/rpl/r/rpl_row_tabledefs_3innodb.result

@@ -123,7 +123,7 @@ Replicate_Ignore_Table
 Replicate_Wild_Do_Table	
 Replicate_Wild_Ignore_Table	
 Last_Errno	1364
-Last_Error	Error in Write_rows event: error during transaction execution on table test.t1_nodef. 
+Last_Error	Error in Write_rows event: error during transaction execution on table test.t1_nodef. Field 'x' doesn't have a default value
 Skip_Counter	0
 Exec_Master_Log_Pos	#
 Relay_Log_Space	#
@@ -141,7 +141,7 @@ Master_SSL_Verify_Server_Cert	No
 Last_IO_Errno	0
 Last_IO_Error	
 Last_SQL_Errno	1364
-Last_SQL_Error	Error in Write_rows event: error during transaction execution on table test.t1_nodef. 
+Last_SQL_Error	Error in Write_rows event: error during transaction execution on table test.t1_nodef. Field 'x' doesn't have a default value
 SET GLOBAL SQL_SLAVE_SKIP_COUNTER=2;
 START SLAVE;
 INSERT INTO t9 VALUES (2);

mysql-test/t/grant.test

@@ -1284,6 +1284,7 @@ set names default;
 #
 --echo FLUSH PRIVILEGES without procs_priv table.
 RENAME TABLE mysql.procs_priv TO mysql.procs_gone;
+--error ER_NO_SUCH_TABLE
 FLUSH PRIVILEGES;
 --echo Assigning privileges without procs_priv table.
 CREATE DATABASE mysqltest1;

server-tools/instance-manager/mysql_connection.cc

@@ -257,7 +257,7 @@ int Mysql_connection::do_command()
       return 1;
     if (thread_registry->is_shutdown())
       return 1;
-    net_send_error(&net, net.last_errno);
+    net_send_error(&net, net.client_last_errno);
     net.error= 0;
     return 0;
   }

sql-common/client.c

@@ -289,8 +289,8 @@ void set_mysql_error(MYSQL *mysql, int errcode, const char *sqlstate)
   DBUG_ASSERT(mysql != 0);
 
   net= &mysql->net;
-  net->last_errno= errcode;
+  net->client_last_errno= errcode;
-  strmov(net->last_error, ER(errcode));
+  strmov(net->client_last_error, ER(errcode));
   strmov(net->sqlstate, sqlstate);
 
   DBUG_VOID_RETURN;
@@ -304,8 +304,8 @@ void set_mysql_error(MYSQL *mysql, int errcode, const char *sqlstate)
 
 void net_clear_error(NET *net)
 {
-  net->last_errno= 0;
+  net->client_last_errno= 0;
-  net->last_error[0]= '\0';
+  net->client_last_error[0]= '\0';
   strmov(net->sqlstate, not_error_sqlstate);
 }
 
@@ -331,9 +331,9 @@ static void set_mysql_extended_error(MYSQL *mysql, int errcode,
   DBUG_ASSERT(mysql != 0);
 
   net= &mysql->net;
-  net->last_errno= errcode;
+  net->client_last_errno= errcode;
   va_start(args, format);
-  my_vsnprintf(net->last_error, sizeof(net->last_error)-1,
+  my_vsnprintf(net->client_last_error, sizeof(net->client_last_error)-1,
                format, args);
   va_end(args);
   strmov(net->sqlstate, sqlstate);
@@ -667,7 +667,7 @@ cli_safe_read(MYSQL *mysql)
       return (packet_error);
 #endif /*MYSQL_SERVER*/
     end_server(mysql);
-    set_mysql_error(mysql, net->last_errno == ER_NET_PACKET_TOO_LARGE ?
+    set_mysql_error(mysql, net->client_last_errno == ER_NET_PACKET_TOO_LARGE ?
                     CR_NET_PACKET_TOO_LARGE: CR_SERVER_LOST, unknown_sqlstate);
     return (packet_error);
   }
@@ -676,7 +676,7 @@ cli_safe_read(MYSQL *mysql)
     if (len > 3)
     {
       char *pos=(char*) net->read_pos+1;
-      net->last_errno=uint2korr(pos);
+      net->client_last_errno=uint2korr(pos);
       pos+=2;
       len-=2;
       if (protocol_41(mysql) && pos[0] == '#')
@@ -684,8 +684,8 @@ cli_safe_read(MYSQL *mysql)
 	strmake(net->sqlstate, pos+1, SQLSTATE_LENGTH);
 	pos+= SQLSTATE_LENGTH+1;
       }
-      (void) strmake(net->last_error,(char*) pos,
+      (void) strmake(net->client_last_error,(char*) pos,
-		     min((uint) len,(uint) sizeof(net->last_error)-1));
+		     min((uint) len,(uint) sizeof(net->client_last_error)-1));
     }
     else
       set_mysql_error(mysql, CR_UNKNOWN_ERROR, unknown_sqlstate);
@@ -701,7 +701,9 @@ cli_safe_read(MYSQL *mysql)
     mysql->server_status&= ~SERVER_MORE_RESULTS_EXISTS;
 
     DBUG_PRINT("error",("Got error: %d/%s (%s)",
-			net->last_errno, net->sqlstate, net->last_error));
+                        net->client_last_errno,
+                        net->sqlstate,
+                        net->client_last_error));
     return(packet_error);
   }
   return len;
@@ -744,7 +746,6 @@ cli_advanced_command(MYSQL *mysql, enum enum_server_command command,
   }
 
   net_clear_error(net);
-  net->report_error=0;
   mysql->info=0;
   mysql->affected_rows= ~(my_ulonglong) 0;
   /*
@@ -759,7 +760,7 @@ cli_advanced_command(MYSQL *mysql, enum enum_server_command command,
   {
     DBUG_PRINT("error",("Can't send command to server. Error: %d",
 			socket_errno));
-    if (net->last_errno == ER_NET_PACKET_TOO_LARGE)
+    if (net->client_last_errno == ER_NET_PACKET_TOO_LARGE)
     {
       set_mysql_error(mysql, CR_NET_PACKET_TOO_LARGE, unknown_sqlstate);
       goto end;
@@ -836,16 +837,15 @@ static my_bool is_NT(void)
 
 
 #ifdef CHECK_LICENSE
-/*
+/**
   Check server side variable 'license'.
+
   If the variable does not exist or does not contain 'Commercial',
   we're talking to non-commercial server from commercial client.
-  SYNOPSIS
+
-    check_license()
+  @retval  0   success
-  RETURN VALUE
+  @retval  !0  network error or the server is not commercial.
-    0  success
+               Error code is saved in mysql->net.client_last_errno.
-   !0  network error or the server is not commercial.
-       Error code is saved in mysql->net.last_errno.
 */
 
 static int check_license(MYSQL *mysql)
@@ -858,7 +858,7 @@ static int check_license(MYSQL *mysql)
 
   if (mysql_real_query(mysql, query, sizeof(query)-1))
   {
-    if (net->last_errno == ER_UNKNOWN_SYSTEM_VARIABLE)
+    if (net->client_last_errno == ER_UNKNOWN_SYSTEM_VARIABLE)
     {
       set_mysql_extended_error(mysql, CR_WRONG_LICENSE, unknown_sqlstate,
                                ER(CR_WRONG_LICENSE), required_license);
@@ -873,7 +873,7 @@ static int check_license(MYSQL *mysql)
     two is ever true for server variables now), or column value
     mismatch, set wrong license error.
   */
-  if (!net->last_errno &&
+  if (!net->client_last_errno &&
       (!row || !row[0] ||
        strncmp(row[0], required_license, sizeof(required_license))))
   {
@@ -881,7 +881,7 @@ static int check_license(MYSQL *mysql)
                              ER(CR_WRONG_LICENSE), required_license);
   }
   mysql_free_result(res);
-  return net->last_errno;
+  return net->client_last_errno;
 }
 #endif /* CHECK_LICENSE */
 
@@ -2090,7 +2090,7 @@ CLI_MYSQL_REAL_CONNECT(MYSQL *mysql,const char *host, const char *user,
 
   if ((pkt_length=cli_safe_read(mysql)) == packet_error)
   {
-    if (mysql->net.last_errno == CR_SERVER_LOST)
+    if (mysql->net.client_last_errno == CR_SERVER_LOST)
       set_mysql_extended_error(mysql, CR_SERVER_LOST, unknown_sqlstate,
                                ER(CR_SERVER_LOST_EXTENDED),
                                "reading initial communication packet",
@@ -2324,7 +2324,7 @@ CLI_MYSQL_REAL_CONNECT(MYSQL *mysql,const char *host, const char *user,
 
   if ((pkt_length=cli_safe_read(mysql)) == packet_error)
   {
-    if (mysql->net.last_errno == CR_SERVER_LOST)
+    if (mysql->net.client_last_errno == CR_SERVER_LOST)
       set_mysql_extended_error(mysql, CR_SERVER_LOST, unknown_sqlstate,
                                ER(CR_SERVER_LOST_EXTENDED),
                                "reading authorization packet",
@@ -2352,7 +2352,7 @@ CLI_MYSQL_REAL_CONNECT(MYSQL *mysql,const char *host, const char *user,
     /* Read what server thinks about out new auth message report */
     if (cli_safe_read(mysql) == packet_error)
     {
-      if (mysql->net.last_errno == CR_SERVER_LOST)
+      if (mysql->net.client_last_errno == CR_SERVER_LOST)
         set_mysql_extended_error(mysql, CR_SERVER_LOST, unknown_sqlstate,
                                  ER(CR_SERVER_LOST_EXTENDED),
                                  "reading final connect information",
@@ -2371,7 +2371,7 @@ CLI_MYSQL_REAL_CONNECT(MYSQL *mysql,const char *host, const char *user,
 
   if (db && mysql_select_db(mysql, db))
   {
-    if (mysql->net.last_errno == CR_SERVER_LOST)
+    if (mysql->net.client_last_errno == CR_SERVER_LOST)
         set_mysql_extended_error(mysql, CR_SERVER_LOST, unknown_sqlstate,
                                  ER(CR_SERVER_LOST_EXTENDED),
                                  "Setting intital database",
@@ -2415,7 +2415,9 @@ CLI_MYSQL_REAL_CONNECT(MYSQL *mysql,const char *host, const char *user,
 error:
   reset_sigpipe(mysql);
   DBUG_PRINT("error",("message: %u/%s (%s)",
-		      net->last_errno, net->sqlstate, net->last_error));
+                      net->client_last_errno,
+                      net->sqlstate,
+                      net->client_last_error));
   {
     /* Free alloced memory */
     end_server(mysql);
@@ -2473,8 +2475,8 @@ my_bool mysql_reconnect(MYSQL *mysql)
 			  mysql->db, mysql->port, mysql->unix_socket,
 			  mysql->client_flag | CLIENT_REMEMBER_OPTIONS))
   {
-    mysql->net.last_errno= tmp_mysql.net.last_errno;
+    mysql->net.client_last_errno= tmp_mysql.net.client_last_errno;
-    strmov(mysql->net.last_error, tmp_mysql.net.last_error);
+    strmov(mysql->net.client_last_error, tmp_mysql.net.client_last_error);
     strmov(mysql->net.sqlstate, tmp_mysql.net.sqlstate);
     DBUG_RETURN(1);
   }
@@ -2483,8 +2485,8 @@ my_bool mysql_reconnect(MYSQL *mysql)
     DBUG_PRINT("error", ("mysql_set_character_set() failed"));
     bzero((char*) &tmp_mysql.options,sizeof(tmp_mysql.options));
     mysql_close(&tmp_mysql);
-    mysql->net.last_errno= tmp_mysql.net.last_errno;
+    mysql->net.client_last_errno= tmp_mysql.net.client_last_errno;
-    strmov(mysql->net.last_error, tmp_mysql.net.last_error);
+    strmov(mysql->net.client_last_error, tmp_mysql.net.client_last_error);
     strmov(mysql->net.sqlstate, tmp_mysql.net.sqlstate);
     DBUG_RETURN(1);
   }
@@ -3077,13 +3079,13 @@ unsigned int STDCALL mysql_num_fields(MYSQL_RES *res)
 
 uint STDCALL mysql_errno(MYSQL *mysql)
 {
-  return mysql->net.last_errno;
+  return mysql->net.client_last_errno;
 }
 
 
 const char * STDCALL mysql_error(MYSQL *mysql)
 {
-  return mysql->net.last_error;
+  return mysql->net.client_last_error;
 }
 
 
@@ -3152,7 +3154,7 @@ int STDCALL mysql_set_character_set(MYSQL *mysql, const char *cs_name)
                              ER(CR_CANT_READ_CHARSET), cs_name, cs_dir_name);
   }
   charsets_dir= save_csdir;
-  return mysql->net.last_errno;
+  return mysql->net.client_last_errno;
 }
 
 

sql/ha_ndbcluster_binlog.cc

@@ -257,6 +257,10 @@ static void run_query(THD *thd, char *buf, char *end,
     thd->options&= ~OPTION_BIN_LOG;
     
   DBUG_PRINT("query", ("%s", thd->query));
+
+  DBUG_ASSERT(!thd->in_sub_stmt);
+  DBUG_ASSERT(!thd->prelocked_mode);
+
   mysql_parse(thd, thd->query, thd->query_length, &found_semicolon);
 
   if (no_print_error && thd->is_slave_error)
@@ -265,14 +269,27 @@ static void run_query(THD *thd, char *buf, char *end,
     Thd_ndb *thd_ndb= get_thd_ndb(thd);
     for (i= 0; no_print_error[i]; i++)
       if ((thd_ndb->m_error_code == no_print_error[i]) ||
-          (thd->net.last_errno == (unsigned)no_print_error[i]))
+          (thd->main_da.sql_errno() == (unsigned) no_print_error[i]))
         break;
     if (!no_print_error[i])
       sql_print_error("NDB: %s: error %s %d(ndb: %d) %d %d",
-                      buf, thd->net.last_error, thd->net.last_errno,
+                      buf,
+                      thd->main_da.message(),
+                      thd->main_da.sql_errno(),
                       thd_ndb->m_error_code,
                       (int) thd->is_error(), thd->is_slave_error);
   }
+  /*
+    XXX: this code is broken. mysql_parse()/mysql_reset_thd_for_next_command()
+    can not be called from within a statement, and
+    run_query() can be called from anywhere, including from within
+    a sub-statement.
+    This particular reset is a temporary hack to avoid an assert
+    for double assignment of the diagnostics area when run_query()
+    is called from ndbcluster_reset_logs(), which is called from
+    mysql_flush().
+  */
+  thd->main_da.reset_diagnostics_area();
 
   thd->options= save_thd_options;
   thd->query_length= save_query_length;
@@ -2301,8 +2318,8 @@ static int open_ndb_binlog_index(THD *thd, TABLE_LIST *tables,
   if (open_tables(thd, &tables, &counter, MYSQL_LOCK_IGNORE_FLUSH))
   {
     sql_print_error("NDB Binlog: Opening ndb_binlog_index: %d, '%s'",
-                    thd->net.last_errno,
+                    thd->main_da.sql_errno(),
-                    thd->net.last_error ? thd->net.last_error : "");
+                    thd->main_da.message());
     thd->proc_info= save_proc_info;
     return -1;
   }

sql/ha_partition.cc

@@ -1753,6 +1753,7 @@ partition_element *ha_partition::find_partition_element(uint part_id)
       return part_elem;
   }
   DBUG_ASSERT(0);
+  my_error(ER_OUT_OF_RESOURCES, MYF(0));
   current_thd->fatal_error();                   // Abort
   return NULL;
 }

sql/item_func.cc

@@ -2949,7 +2949,6 @@ udf_handler::fix_fields(THD *thd, Item_result_field *func,
         }
       }
     }
-    thd->net.last_error[0]=0;
     Udf_func_init init= u_d->func_init;
     if ((error=(uchar) init(&initid, &f_args, init_msg_buff)))
     {

sql/log_event.cc

@@ -1611,7 +1611,8 @@ Query_log_event::Query_log_event(THD* thd_arg, const char* query_arg,
   if (killed_status_arg == THD::KILLED_NO_VALUE)
     killed_status_arg= thd_arg->killed;
   error_code=
-    (killed_status_arg == THD::NOT_KILLED) ? thd_arg->net.last_errno :
+    (killed_status_arg == THD::NOT_KILLED) ?
+    (thd_arg->is_error() ? thd_arg->main_da.sql_errno() : 0) :
     ((thd_arg->system_thread & SYSTEM_THREAD_DELAYED_INSERT) ? 0 :
      thd_arg->killed_errno());
   
@@ -2332,7 +2333,7 @@ START SLAVE; . Query: '%s'", expected_error, thd->query);
     }
 
     /* If the query was not ignored, it is printed to the general log */
-    if (thd->net.last_errno != ER_SLAVE_IGNORED_TABLE)
+    if (!thd->is_error() || thd->main_da.sql_errno() != ER_SLAVE_IGNORED_TABLE)
       general_log_write(thd, COM_QUERY, thd->query, thd->query_length);
 
 compare_errors:
@@ -2341,9 +2342,10 @@ compare_errors:
       If we expected a non-zero error code, and we don't get the same error
       code, and none of them should be ignored.
     */
-    DBUG_PRINT("info",("expected_error: %d  last_errno: %d",
+    actual_error= thd->is_error() ? thd->main_da.sql_errno() : 0;
- 		       expected_error, thd->net.last_errno));
+    DBUG_PRINT("info",("expected_error: %d  sql_errno: %d",
-    if ((expected_error != (actual_error= thd->net.last_errno)) &&
+ 		       expected_error, actual_error));
+    if ((expected_error != actual_error) &&
  	expected_error &&
  	!ignored_error_code(actual_error) &&
  	!ignored_error_code(expected_error))
@@ -2355,7 +2357,7 @@ Error on master: '%s' (%d), Error on slave: '%s' (%d). \
 Default database: '%s'. Query: '%s'",
                       ER_SAFE(expected_error),
                       expected_error,
-                      actual_error ? thd->net.last_error: "no error",
+                      actual_error ? thd->main_da.message() : "no error",
                       actual_error,
                       print_slave_db_safe(db), query_arg);
       thd->is_slave_error= 1;
@@ -2377,7 +2379,7 @@ Default database: '%s'. Query: '%s'",
     {
       rli->report(ERROR_LEVEL, actual_error,
                       "Error '%s' on query. Default database: '%s'. Query: '%s'",
-                      (actual_error ? thd->net.last_error :
+                      (actual_error ? thd->main_da.message() :
                        "unexpected success or fatal error"),
                       print_slave_db_safe(thd->db), query_arg);
       thd->is_slave_error= 1;
@@ -3720,8 +3722,11 @@ error:
     /* this err/sql_errno code is copy-paste from net_send_error() */
     const char *err;
     int sql_errno;
-    if ((err=thd->net.last_error)[0])
+    if (thd->is_error())
-      sql_errno=thd->net.last_errno;
+    {
+      err= thd->main_da.message();
+      sql_errno= thd->main_da.sql_errno();
+    }
     else
     {
       sql_errno=ER_UNKNOWN_ERROR;
@@ -6222,10 +6227,10 @@ int Rows_log_event::do_apply_event(Relay_log_info const *rli)
             Error reporting borrowed from Query_log_event with many excessive
             simplifications (we don't honour --slave-skip-errors)
           */
-          uint actual_error= thd->net.last_errno;
+          uint actual_error= thd->main_da.sql_errno();
           rli->report(ERROR_LEVEL, actual_error,
                       "Error '%s' in %s event: when locking tables",
-                      (actual_error ? thd->net.last_error :
+                      (actual_error ? thd->main_da.message():
                        "unexpected success or fatal error"),
                       get_type_str());
           thd->is_fatal_error= 1;
@@ -6266,10 +6271,10 @@ int Rows_log_event::do_apply_event(Relay_log_info const *rli)
             Error reporting borrowed from Query_log_event with many excessive
             simplifications (we don't honour --slave-skip-errors)
           */
-          uint actual_error= thd->net.last_errno;
+          uint actual_error= thd->main_da.sql_errno();
           rli->report(ERROR_LEVEL, actual_error,
                       "Error '%s' on reopening tables",
-                      (actual_error ? thd->net.last_error :
+                      (actual_error ? thd->main_da.message() :
                        "unexpected success or fatal error"));
           thd->is_slave_error= 1;
         }
@@ -6425,10 +6430,11 @@ int Rows_log_event::do_apply_event(Relay_log_info const *rli)
         break;
 
       default:
-	rli->report(ERROR_LEVEL, thd->net.last_errno,
+	rli->report(ERROR_LEVEL,
+                    thd->is_error() ? thd->main_da.sql_errno() : 0,
                     "Error in %s event: row application failed. %s",
                     get_type_str(),
-                    thd->net.last_error ? thd->net.last_error : "");
+                    thd->is_error() ? thd->main_da.message() : "");
 	thd->is_slave_error= 1;
 	break;
       }
@@ -6475,12 +6481,13 @@ int Rows_log_event::do_apply_event(Relay_log_info const *rli)
 
   if (error)
   {                     /* error has occured during the transaction */
-    rli->report(ERROR_LEVEL, thd->net.last_errno,
+    rli->report(ERROR_LEVEL,
+                thd->is_error() ? thd->main_da.sql_errno() : 0,
                 "Error in %s event: error during transaction execution "
                 "on table %s.%s. %s",
                 get_type_str(), table->s->db.str,
                 table->s->table_name.str,
-                thd->net.last_error ? thd->net.last_error : "");
+                thd->is_error() ? thd->main_da.message() : "");
 
     /*
       If one day we honour --skip-slave-errors in row-based replication, and
@@ -7094,10 +7101,10 @@ int Table_map_log_event::do_apply_event(Relay_log_info const *rli)
           Error reporting borrowed from Query_log_event with many excessive
           simplifications (we don't honour --slave-skip-errors)
         */
-        uint actual_error= thd->net.last_errno;
+        uint actual_error= thd->main_da.sql_errno();
         rli->report(ERROR_LEVEL, actual_error,
                     "Error '%s' on opening table `%s`.`%s`",
-                    (actual_error ? thd->net.last_error :
+                    (actual_error ? thd->main_da.message() :
                      "unexpected success or fatal error"),
                     table_list->db, table_list->table_name);
         thd->is_slave_error= 1;
@@ -7625,8 +7632,11 @@ Write_rows_log_event::do_exec_row(const Relay_log_info *const rli)
   DBUG_ASSERT(m_table != NULL);
   int error= write_row(rli, TRUE /* overwrite */);
   
-  if (error && !thd->net.last_errno)
+  if (error && !thd->is_error())
-    thd->net.last_errno= error;
+  {
+    DBUG_ASSERT(0);
+    my_error(ER_UNKNOWN_ERROR, MYF(0));
+  }
       
   return error; 
 }

sql/log_event_old.cc

@@ -74,10 +74,10 @@ Old_rows_log_event::do_apply_event(Rows_log_event *ev, const Relay_log_info *rli
             Error reporting borrowed from Query_log_event with many excessive
             simplifications (we don't honour --slave-skip-errors)
           */
-          uint actual_error= thd->net.last_errno;
+          uint actual_error= thd->main_da.sql_errno();
           rli->report(ERROR_LEVEL, actual_error,
                       "Error '%s' in %s event: when locking tables",
-                      (actual_error ? thd->net.last_error :
+                      (actual_error ? thd->main_da.message() :
                        "unexpected success or fatal error"),
                       ev->get_type_str());
           thd->is_fatal_error= 1;
@@ -118,10 +118,10 @@ Old_rows_log_event::do_apply_event(Rows_log_event *ev, const Relay_log_info *rli
             Error reporting borrowed from Query_log_event with many excessive
             simplifications (we don't honour --slave-skip-errors)
           */
-          uint actual_error= thd->net.last_errno;
+          uint actual_error= thd->main_da.sql_errno();
           rli->report(ERROR_LEVEL, actual_error,
                       "Error '%s' on reopening tables",
-                      (actual_error ? thd->net.last_error :
+                      (actual_error ? thd->main_da.message() :
                        "unexpected success or fatal error"));
           thd->is_slave_error= 1;
         }
@@ -251,10 +251,10 @@ Old_rows_log_event::do_apply_event(Rows_log_event *ev, const Relay_log_info *rli
   break;
 
       default:
-  rli->report(ERROR_LEVEL, thd->net.last_errno,
+  rli->report(ERROR_LEVEL, thd->main_da.sql_errno(),
                     "Error in %s event: row application failed. %s",
                     ev->get_type_str(),
-                    thd->net.last_error ? thd->net.last_error : "");
+                    thd->is_error() ? thd->main_da.message() : "");
   thd->is_slave_error= 1;
   break;
       }
@@ -280,12 +280,12 @@ Old_rows_log_event::do_apply_event(Rows_log_event *ev, const Relay_log_info *rli
 
   if (error)
   {                     /* error has occured during the transaction */
-    rli->report(ERROR_LEVEL, thd->net.last_errno,
+    rli->report(ERROR_LEVEL, thd->main_da.sql_errno(),
                 "Error in %s event: error during transaction execution "
                 "on table %s.%s. %s",
                 ev->get_type_str(), table->s->db.str,
                 table->s->table_name.str,
-                thd->net.last_error ? thd->net.last_error : "");
+                thd->is_error() ? thd->main_da.message() : "");
 
     /*
       If one day we honour --skip-slave-errors in row-based replication, and

sql/mysqld.cc

@@ -2587,21 +2587,8 @@ int my_message_sql(uint error, const char *str, myf MyFlags)
                           MYSQL_ERROR::WARN_LEVEL_ERROR))
       DBUG_RETURN(0);
 
-    if (thd->spcont &&
-        thd->spcont->handle_error(error, MYSQL_ERROR::WARN_LEVEL_ERROR, thd))
-    {
-      DBUG_RETURN(0);
-    }
-
     thd->is_slave_error=  1; // needed to catch query errors during replication
 
-    if (!thd->no_warnings_for_error)
-    {
-      thd->no_warnings_for_error= TRUE;
-      push_warning(thd, MYSQL_ERROR::WARN_LEVEL_ERROR, error, str);
-      thd->no_warnings_for_error= FALSE;
-    }
-
     /*
       thd->lex->current_select == 0 if lex structure is not inited
       (not query command (COM_QUERY))
@@ -2618,14 +2605,39 @@ int my_message_sql(uint error, const char *str, myf MyFlags)
     }
     else
     {
-      NET *net= &thd->net;
+      if (! thd->main_da.is_error())            // Return only first message
-      net->report_error= 1;
-      query_cache_abort(net);
-      if (!net->last_error[0])			// Return only first message
       {
-	strmake(net->last_error, str, sizeof(net->last_error)-1);
+        if (error == 0)
-	net->last_errno= error ? error : ER_UNKNOWN_ERROR;
+          error= ER_UNKNOWN_ERROR;
+        if (str == NULL)
+          str= ER(error);
+        thd->main_da.set_error_status(thd, error, str);
       }
+      query_cache_abort(&thd->net);
+    }
+    /*
+      If a continue handler is found, the error message will be cleared
+      by the stored procedures code.
+    */
+    if (thd->spcont &&
+        thd->spcont->handle_error(error, MYSQL_ERROR::WARN_LEVEL_ERROR, thd))
+    {
+      /*
+        Do not push any warnings, a handled error must be completely
+        silenced.
+      */
+      DBUG_RETURN(0);
+    }
+
+    if (!thd->no_warnings_for_error)
+    {
+      /*
+        Suppress infinite recursion if there a memory allocation error
+        inside push_warning.
+      */
+      thd->no_warnings_for_error= TRUE;
+      push_warning(thd, MYSQL_ERROR::WARN_LEVEL_ERROR, error, str);
+      thd->no_warnings_for_error= FALSE;
     }
   }
   if (!thd || MyFlags & ME_NOREFRESH)

sql/net_serv.cc

@@ -123,20 +123,18 @@ my_bool my_net_init(NET *net, Vio* vio)
 				     MYF(MY_WME))))
     DBUG_RETURN(1);
   net->buff_end=net->buff+net->max_packet;
-  net->no_send_ok= net->no_send_error= 0;
   net->error=0; net->return_errno=0; net->return_status=0;
   net->pkt_nr=net->compress_pkt_nr=0;
   net->write_pos=net->read_pos = net->buff;
-  net->last_error[0]=0;
+  net->client_last_error[0]=0;
   net->compress=0; net->reading_or_writing=0;
   net->where_b = net->remain_in_buf=0;
-  net->last_errno=0;
+  net->client_last_errno=0;
 #ifdef USE_QUERY_CACHE
   query_cache_init_query(net);
 #else
   net->query_cache_query= 0;
 #endif
-  net->report_error= 0;
 
   if (vio != 0)					/* If real connection */
   {
@@ -176,9 +174,12 @@ my_bool net_realloc(NET *net, size_t length)
   {
     DBUG_PRINT("error", ("Packet too large. Max size: %lu",
                          net->max_packet_size));
+    /* @todo: 1 and 2 codes are identical. */
     net->error= 1;
-    net->report_error= 1;
+    net->client_last_errno= ER_NET_PACKET_TOO_LARGE;
-    net->last_errno= ER_NET_PACKET_TOO_LARGE;
+#ifdef MYSQL_SERVER
+    my_error(ER_NET_PACKET_TOO_LARGE, MYF(0));
+#endif
     DBUG_RETURN(1);
   }
   pkt_length = (length+IO_SIZE-1) & ~(IO_SIZE-1); 
@@ -190,9 +191,10 @@ my_bool net_realloc(NET *net, size_t length)
                                   NET_HEADER_SIZE + COMP_HEADER_SIZE,
                                   MYF(MY_WME))))
   {
+    /* @todo: 1 and 2 codes are identical. */
     net->error= 1;
-    net->report_error= 1;
+    net->client_last_errno= ER_OUT_OF_RESOURCES;
-    net->last_errno= ER_OUT_OF_RESOURCES;
+    /* In the server the error is reported by MY_WME flag. */
     DBUG_RETURN(1);
   }
   net->buff=net->write_pos=buff;
@@ -582,12 +584,9 @@ net_real_write(NET *net,const uchar *packet, size_t len)
     if (!(b= (uchar*) my_malloc(len + NET_HEADER_SIZE +
                                 COMP_HEADER_SIZE, MYF(MY_WME))))
     {
-#ifdef MYSQL_SERVER
-      net->last_errno= ER_OUT_OF_RESOURCES;
       net->error= 2;
-      /* TODO is it needed to set this variable if we have no socket */
+      net->client_last_errno= ER_OUT_OF_RESOURCES;
-      net->report_error= 1;
+      /* In the server, the error is reported by MY_WME flag. */
-#endif
       net->reading_or_writing= 0;
       DBUG_RETURN(1);
     }
@@ -638,11 +637,11 @@ net_real_write(NET *net,const uchar *packet, size_t len)
 		    "%s: my_net_write: fcntl returned error %d, aborting thread\n",
 		    my_progname,vio_errno(net->vio));
 #endif /* EXTRA_DEBUG */
-#ifdef MYSQL_SERVER	    
-	    net->last_errno= ER_NET_ERROR_ON_WRITE;
-#endif
 	    net->error= 2;                     /* Close socket */
-            net->report_error= 1;
+            net->client_last_errno= ER_NET_PACKET_TOO_LARGE;
+#ifdef MYSQL_SERVER
+            my_error(ER_NET_PACKET_TOO_LARGE, MYF(0));
+#endif
 	    goto end;
 	  }
 	  retry_count=0;
@@ -669,10 +668,10 @@ net_real_write(NET *net,const uchar *packet, size_t len)
       }
 #endif /* defined(THREAD_SAFE_CLIENT) && !defined(MYSQL_SERVER) */
       net->error= 2;				/* Close socket */
-      net->report_error= 1;
+      net->client_last_errno= (interrupted ? ER_NET_WRITE_INTERRUPTED :
-#ifdef MYSQL_SERVER
-      net->last_errno= (interrupted ? ER_NET_WRITE_INTERRUPTED :
                                ER_NET_ERROR_ON_WRITE);
+#ifdef MYSQL_SERVER
+      my_error(net->client_last_errno, MYF(0));
 #endif /* MYSQL_SERVER */
       break;
     }
@@ -849,9 +848,9 @@ my_real_read(NET *net, size_t *complen)
 #endif /* EXTRA_DEBUG */
 		len= packet_error;
 		net->error= 2;                 /* Close socket */
-	        net->report_error= 1;
+	        net->client_last_errno= ER_NET_FCNTL_ERROR;
 #ifdef MYSQL_SERVER
-		net->last_errno= ER_NET_FCNTL_ERROR;
+		my_error(ER_NET_FCNTL_ERROR, MYF(0));
 #endif
 		goto end;
 	      }
@@ -881,10 +880,11 @@ my_real_read(NET *net, size_t *complen)
 			      remain, vio_errno(net->vio), (long) length));
 	  len= packet_error;
 	  net->error= 2;				/* Close socket */
-	  net->report_error= 1;
+          net->client_last_errno= (vio_was_interrupted(net->vio) ?
-#ifdef MYSQL_SERVER
+                                   ER_NET_READ_INTERRUPTED :
-	  net->last_errno= (vio_was_interrupted(net->vio) ? ER_NET_READ_INTERRUPTED :
                                    ER_NET_READ_ERROR);
+#ifdef MYSQL_SERVER
+          my_error(net->client_last_errno, MYF(0));
 #endif
 	  goto end;
 	}
@@ -915,9 +915,9 @@ my_real_read(NET *net, size_t *complen)
 #endif
 	  }
 	  len= packet_error;
-	  net->report_error= 1;
+          /* Not a NET error on the client. XXX: why? */
 #ifdef MYSQL_SERVER
-	  net->last_errno=ER_NET_PACKETS_OUT_OF_ORDER;
+	  my_error(ER_NET_PACKETS_OUT_OF_ORDER, MYF(0));
 #endif
 	  goto end;
 	}
@@ -1101,9 +1101,9 @@ my_net_read(NET *net)
 			&complen))
       {
 	net->error= 2;			/* caller will close socket */
-	net->report_error= 1;
+        net->client_last_errno= ER_NET_UNCOMPRESS_ERROR;
 #ifdef MYSQL_SERVER
-	net->last_errno=ER_NET_UNCOMPRESS_ERROR;
+	my_error(ER_NET_UNCOMPRESS_ERROR, MYF(0));
 #endif
 	return packet_error;
       }

sql/opt_range.cc

@@ -1271,7 +1271,7 @@ int QUICK_RANGE_SELECT::init_ror_merged_scan(bool reuse_handler)
       the storage engine calls in question happen to never fail with the 
       existing storage engines. 
     */
-    thd->net.report_error= 1; /* purecov: inspected */
+    my_error(ER_OUT_OF_RESOURCES, MYF(0)); /* purecov: inspected */
     /* Caller will free the memory */
     goto failure;  /* purecov: inspected */
   }

sql/opt_sum.cc

@@ -170,6 +170,7 @@ int opt_sum_query(TABLE_LIST *tables, List<Item> &all_fields,COND *conds)
       if(error)
       {
         tl->table->file->print_error(error, MYF(0));
+        tl->table->in_use->fatal_error();
         return error;
       }
       count*= tl->table->file->stats.records;
@@ -418,6 +419,7 @@ int opt_sum_query(TABLE_LIST *tables, List<Item> &all_fields,COND *conds)
 	      return HA_ERR_KEY_NOT_FOUND;	     // No rows matching WHERE
 	    /* HA_ERR_LOCK_DEADLOCK or some other error */
  	    table->file->print_error(error, MYF(0));
+            table->in_use->fatal_error();
             return(error);
 	  }
           removed_tables|= table->map;

sql/protocol.cc

@@ -23,13 +23,20 @@
 #endif
 
 #include "mysql_priv.h"
-#include "sp_rcontext.h"
 #include <stdarg.h>
 
 static const unsigned int PACKET_BUFFER_EXTRA_ALLOC= 1024;
+/* Declared non-static only because of the embedded library. */
 void net_send_error_packet(THD *thd, uint sql_errno, const char *err);
+void
+net_send_ok(THD *thd,
+            uint server_status, uint total_warn_count,
+            ha_rows affected_rows, ulonglong id, const char *message);
+void
+net_send_eof(THD *thd, uint server_status, uint total_warn_count);
 #ifndef EMBEDDED_LIBRARY
-static void write_eof_packet(THD *thd, NET *net);
+static void write_eof_packet(THD *thd, NET *net,
+                             uint server_status, uint total_warn_count);
 #endif
 
 #ifndef EMBEDDED_LIBRARY
@@ -68,58 +75,23 @@ bool Protocol_binary::net_store_data(const uchar *from, size_t length)
 void net_send_error(THD *thd, uint sql_errno, const char *err)
 {
   NET *net= &thd->net;
-  bool generate_warning= thd->killed != THD::KILL_CONNECTION;
   DBUG_ENTER("net_send_error");
-  DBUG_PRINT("enter",("sql_errno: %d  err: %s", sql_errno,
-		      err ? err : net->last_error[0] ?
-		      net->last_error : "NULL"));
 
   DBUG_ASSERT(!thd->spcont);
+  DBUG_ASSERT(sql_errno);
+  DBUG_ASSERT(err && err[0]);
 
-  if (thd->killed == THD::KILL_QUERY || thd->killed == THD::KILL_BAD_DATA)
+  DBUG_PRINT("enter",("sql_errno: %d  err: %s", sql_errno, err));
-  {
-    thd->killed= THD::NOT_KILLED;
-    thd->mysys_var->abort= 0;
-  }
 
-  if (net && net->no_send_error)
+  /*
-  {
+    It's one case when we can push an error even though there
-    thd->clear_error();
+    is an OK or EOF already.
-    thd->is_fatal_error= 0;			// Error message is given
+  */
-    DBUG_PRINT("info", ("sending error messages prohibited"));
+  thd->main_da.can_overwrite_status= TRUE;
-    DBUG_VOID_RETURN;
-  }
-
-  thd->is_slave_error=  1; // needed to catch query errors during replication
-  if (!err)
-  {
-    if (sql_errno)
-      err=ER(sql_errno);
-    else
-    {
-      if ((err=net->last_error)[0])
-      {
-	sql_errno=net->last_errno;
-        generate_warning= 0;            // This warning has already been given
-      }
-      else
-      {
-	sql_errno=ER_UNKNOWN_ERROR;
-	err=ER(sql_errno);	 /* purecov: inspected */
-      }
-    }
-  }
-
-  if (generate_warning)
-  {
-    /* Error that we have not got with my_error() */
-    push_warning(thd, MYSQL_ERROR::WARN_LEVEL_ERROR, sql_errno, err);
-  }
 
   net_send_error_packet(thd, sql_errno, err);
 
-  thd->is_fatal_error= 0;			// Error message is given
+  thd->main_da.can_overwrite_status= FALSE;
-  thd->net.report_error= 0;
 
   /* Abort multi-result sets */
   thd->server_status&= ~SERVER_MORE_RESULTS_EXISTS;
@@ -149,23 +121,21 @@ void net_send_error(THD *thd, uint sql_errno, const char *err)
     warning_count	Stored in 2 bytes; New in 4.1 protocol
     message		Stored as packed length (1-9 bytes) + message
 			Is not stored if no message
-
-   If net->no_send_ok return without sending packet
 */    
 
 #ifndef EMBEDDED_LIBRARY
 void
-send_ok(THD *thd, ha_rows affected_rows, ulonglong id, const char *message)
+net_send_ok(THD *thd,
+            uint server_status, uint total_warn_count,
+            ha_rows affected_rows, ulonglong id, const char *message)
 {
   NET *net= &thd->net;
   uchar buff[MYSQL_ERRMSG_SIZE+10],*pos;
   DBUG_ENTER("send_ok");
 
-  if (net->no_send_ok || !net->vio)	// hack for re-parsing queries
+  if (! net->vio)	// hack for re-parsing queries
   {
-    DBUG_PRINT("info", ("no send ok: %s, vio present: %s",
+    DBUG_PRINT("info", ("vio present: NO"));
-                        (net->no_send_ok ? "YES" : "NO"),
-                        (net->vio ? "YES" : "NO")));
     DBUG_VOID_RETURN;
   }
 
@@ -178,28 +148,29 @@ send_ok(THD *thd, ha_rows affected_rows, ulonglong id, const char *message)
 	       ("affected_rows: %lu  id: %lu  status: %u  warning_count: %u",
 		(ulong) affected_rows,		
 		(ulong) id,
-		(uint) (thd->server_status & 0xffff),
+		(uint) (server_status & 0xffff),
-		(uint) thd->total_warn_count));
+		(uint) total_warn_count));
-    int2store(pos,thd->server_status);
+    int2store(pos, server_status);
     pos+=2;
 
     /* We can only return up to 65535 warnings in two bytes */
-    uint tmp= min(thd->total_warn_count, 65535);
+    uint tmp= min(total_warn_count, 65535);
     int2store(pos, tmp);
     pos+= 2;
   }
   else if (net->return_status)			// For 4.0 protocol
   {
-    int2store(pos,thd->server_status);
+    int2store(pos, server_status);
     pos+=2;
   }
-  if (message)
+  thd->main_da.can_overwrite_status= TRUE;
+
+  if (message && message[0])
     pos= net_store_data(pos, (uchar*) message, strlen(message));
   VOID(my_net_write(net, buff, (size_t) (pos-buff)));
   VOID(net_flush(net));
-  /* We can't anymore send an error to the client */
+
-  thd->net.report_error= 0;
+  thd->main_da.can_overwrite_status= FALSE;
-  thd->net.no_send_error= 1;
   DBUG_PRINT("info", ("OK sent, so no more error sending allowed"));
 
   DBUG_VOID_RETURN;
@@ -211,7 +182,7 @@ static uchar eof_buff[1]= { (uchar) 254 };      /* Marker for end of fields */
   Send eof (= end of result set) to the client
 
   SYNOPSIS
-    send_eof()
+    net_send_eof()
     thd			Thread handler
     no_flush		Set to 1 if there will be more data to the client,
 			like in send_fields().
@@ -230,15 +201,17 @@ static uchar eof_buff[1]= { (uchar) 254 };      /* Marker for end of fields */
 */    
 
 void
-send_eof(THD *thd)
+net_send_eof(THD *thd, uint server_status, uint total_warn_count)
 {
   NET *net= &thd->net;
-  DBUG_ENTER("send_eof");
+  DBUG_ENTER("net_send_eof");
+  /* Set to TRUE if no active vio, to work well in case of --init-file */
   if (net->vio != 0)
   {
-    write_eof_packet(thd, net);
+    thd->main_da.can_overwrite_status= TRUE;
+    write_eof_packet(thd, net, server_status, total_warn_count);
     VOID(net_flush(net));
-    thd->net.no_send_error= 1;
+    thd->main_da.can_overwrite_status= FALSE;
     DBUG_PRINT("info", ("EOF sent, so no more error sending allowed"));
   }
   DBUG_VOID_RETURN;
@@ -250,7 +223,9 @@ send_eof(THD *thd)
   write it to the network output buffer.
 */
 
-static void write_eof_packet(THD *thd, NET *net)
+static void write_eof_packet(THD *thd, NET *net,
+                             uint server_status,
+                             uint total_warn_count)
 {
   if (thd->client_capabilities & CLIENT_PROTOCOL_41)
   {
@@ -259,7 +234,7 @@ static void write_eof_packet(THD *thd, NET *net)
       Don't send warn count during SP execution, as the warn_list
       is cleared between substatements, and mysqltest gets confused
     */
-    uint tmp= (thd->spcont ? 0 : min(thd->total_warn_count, 65535));
+    uint tmp= min(total_warn_count, 65535);
     buff[0]= 254;
     int2store(buff+1, tmp);
     /*
@@ -268,8 +243,8 @@ static void write_eof_packet(THD *thd, NET *net)
       other queries (see the if test in dispatch_command / COM_QUERY)
     */
     if (thd->is_fatal_error)
-      thd->server_status&= ~SERVER_MORE_RESULTS_EXISTS;
+      server_status&= ~SERVER_MORE_RESULTS_EXISTS;
-    int2store(buff+3, thd->server_status);
+    int2store(buff + 3, server_status);
     VOID(my_net_write(net, buff, 5));
   }
   else
@@ -360,6 +335,96 @@ static uchar *net_store_length_fast(uchar *packet, uint length)
   return packet+2;
 }
 
+/**
+  Send the status of the current statement execution over network.
+
+  @param  thd   in fact, carries two parameters, NET for the transport and
+                Diagnostics_area as the source of status information.
+
+  In MySQL, there are two types of SQL statements: those that return
+  a result set and those that return status information only.
+
+  If a statement returns a result set, it consists of 3 parts:
+  - result set meta-data
+  - variable number of result set rows (can be 0)
+  - followed and terminated by EOF or ERROR packet
+
+  Once the  client has seen the meta-data information, it always
+  expects an EOF or ERROR to terminate the result set. If ERROR is
+  received, the result set rows are normally discarded (this is up
+  to the client implementation, libmysql at least does discard them).
+  EOF, on the contrary, means "successfully evaluated the entire
+  result set". Since we don't know how many rows belong to a result
+  set until it's evaluated, EOF/ERROR is the indicator of the end
+  of the row stream. Note, that we can not buffer result set rows
+  on the server -- there may be an arbitrary number of rows. But
+  we do buffer the last packet (EOF/ERROR) in the Diagnostics_area and
+  delay sending it till the very end of execution (here), to be able to
+  change EOF to an ERROR if commit failed or some other error occurred
+  during the last cleanup steps taken after execution.
+
+  A statement that does not return a result set doesn't send result
+  set meta-data either. Instead it returns one of:
+  - OK packet
+  - ERROR packet.
+  Similarly to the EOF/ERROR of the previous statement type, OK/ERROR
+  packet is "buffered" in the diagnostics area and sent to the client
+  in the end of statement.
+
+  @pre  The diagnostics area is assigned or disabled. It can not be empty
+        -- we assume that every SQL statement or COM_* command
+        generates OK, ERROR, or EOF status.
+
+  @post The status information is encoded to protocol format and sent to the
+        client.
+
+  @return We conventionally return void, since the only type of error
+          that can happen here is a NET (transport) error, and that one
+          will become visible when we attempt to read from the NET the
+          next command.
+          Diagnostics_area::is_sent is set for debugging purposes only.
+*/
+
+void net_end_statement(THD *thd)
+{
+  DBUG_ASSERT(! thd->main_da.is_sent);
+
+  /* Can not be true, but do not take chances in production. */
+  if (thd->main_da.is_sent)
+    return;
+
+  switch (thd->main_da.status()) {
+  case Diagnostics_area::DA_ERROR:
+    /* The query failed, send error to log and abort bootstrap. */
+    net_send_error(thd,
+                   thd->main_da.sql_errno(),
+                   thd->main_da.message());
+    break;
+  case Diagnostics_area::DA_EOF:
+    net_send_eof(thd,
+                 thd->main_da.server_status(),
+                 thd->main_da.total_warn_count());
+    break;
+  case Diagnostics_area::DA_OK:
+    net_send_ok(thd,
+                thd->main_da.server_status(),
+                thd->main_da.total_warn_count(),
+                thd->main_da.affected_rows(),
+                thd->main_da.last_insert_id(),
+                thd->main_da.message());
+    break;
+  case Diagnostics_area::DA_DISABLED:
+    break;
+  case Diagnostics_area::DA_EMPTY:
+  default:
+    DBUG_ASSERT(0);
+    net_send_ok(thd, thd->server_status, thd->total_warn_count,
+                0, 0, NULL);
+    break;
+  }
+  thd->main_da.is_sent= TRUE;
+}
+
 
 /****************************************************************************
   Functions used by the protocol functions (like send_ok) to store strings
@@ -408,6 +473,17 @@ void Protocol::init(THD *thd_arg)
 #endif
 }
 
+/**
+  Finish the result set with EOF packet, as is expected by the client,
+  if there is an error evaluating the next row and a continue handler
+  for the error.
+*/
+
+void Protocol::end_partial_result_set(THD *thd)
+{
+  net_send_eof(thd, thd->server_status, 0 /* no warnings, we're inside SP */);
+}
+
 
 bool Protocol::flush()
 {
@@ -573,7 +649,14 @@ bool Protocol::send_fields(List<Item> *list, uint flags)
   }
 
   if (flags & SEND_EOF)
-    write_eof_packet(thd, &thd->net);
+  {
+    /*
+      Mark the end of meta-data result set, and store thd->server_status,
+      to show that there is no cursor.
+      Send no warning information, as it will be sent at statement end.
+    */
+    write_eof_packet(thd, &thd->net, thd->server_status, thd->total_warn_count);
+  }
   DBUG_RETURN(prepare_for_send(list));
 
 err:

sql/protocol.h

@@ -75,6 +75,7 @@ public:
     return 0;
   }
   virtual bool flush();
+  virtual void end_partial_result_set(THD *thd);
   virtual void prepare_for_resend()=0;
 
   virtual bool store_null()=0;
@@ -173,9 +174,7 @@ public:
 
 void send_warning(THD *thd, uint sql_errno, const char *err=0);
 void net_send_error(THD *thd, uint sql_errno=0, const char *err=0);
-void send_ok(THD *thd, ha_rows affected_rows=0L, ulonglong id=0L,
+void net_end_statement(THD *thd);
-	     const char *info=0);
-void send_eof(THD *thd);
 bool send_old_password_request(THD *thd);
 uchar *net_store_data(uchar *to,const uchar *from, size_t length);
 uchar *net_store_data(uchar *to,int32 from);

sql/repl_failsafe.cc

@@ -685,7 +685,7 @@ int connect_to_master(THD *thd, MYSQL* mysql, Master_info* mi)
 
   if (!mi->host || !*mi->host)			/* empty host */
   {
-    strmov(mysql->net.last_error, "Master is not configured");
+    strmov(mysql->net.client_last_error, "Master is not configured");
     DBUG_RETURN(1);
   }
   mysql_options(mysql, MYSQL_OPT_CONNECT_TIMEOUT, (char *) &slave_net_timeout);
@@ -880,6 +880,8 @@ bool load_master_data(THD* thd)
 	cleanup_mysql_results(db_res, cur_table_res - 1, table_res);
 	goto err;
       }
+      /* Clear the result of mysql_create_db(). */
+      thd->main_da.reset_diagnostics_area();
 
       if (mysql_select_db(&mysql, db) ||
 	  mysql_real_query(&mysql, STRING_WITH_LEN("SHOW TABLES")) ||

sql/rpl_record.cc

@@ -338,12 +338,13 @@ int prepare_record(const Slave_reporting_capability *const log,
     if (check && ((f->flags & mask) == mask))
     {
       DBUG_ASSERT(log);
-      log->report(ERROR_LEVEL, ER_NO_DEFAULT_FOR_FIELD,
+      error= ER_NO_DEFAULT_FOR_FIELD;
+      log->report(ERROR_LEVEL, error,
                   "Field `%s` of table `%s`.`%s` "
                   "has no default value and cannot be NULL",
                   f->field_name, table->s->db.str,
                   table->s->table_name.str);
-      error = ER_NO_DEFAULT_FOR_FIELD;
+      my_error(error, MYF(0), f->field_name);
     }
     else
       f->set_default();

sql/rpl_rli.cc

@@ -166,7 +166,7 @@ int init_relay_log_info(Relay_log_info* rli,
     {
       sql_print_error("Failed to create a new relay log info file (\
 file '%s', errno %d)", fname, my_errno);
-      msg= current_thd->net.last_error;
+      msg= current_thd->main_da.message();
       goto err;
     }
     if (init_io_cache(&rli->info_file, info_fd, IO_SIZE*2, READ_CACHE, 0L,0,
@@ -174,7 +174,7 @@ file '%s', errno %d)", fname, my_errno);
     {
       sql_print_error("Failed to create a cache on relay log info file '%s'",
                       fname);
-      msg= current_thd->net.last_error;
+      msg= current_thd->main_da.message();
       goto err;
     }
 

sql/slave.cc

@@ -981,18 +981,25 @@ static int create_table_from_dump(THD* thd, MYSQL *mysql, const char* db,
   }
   thd->query= query;
   thd->is_slave_error = 0;
-  thd->net.no_send_ok = 1;
 
   bzero((char*) &tables,sizeof(tables));
   tables.db = (char*)db;
   tables.alias= tables.table_name= (char*)table_name;
 
   /* Drop the table if 'overwrite' is true */
-  if (overwrite && mysql_rm_table(thd,&tables,1,0)) /* drop if exists */
+  if (overwrite)
+  {
+    if (mysql_rm_table(thd,&tables,1,0)) /* drop if exists */
     {
       sql_print_error("create_table_from_dump: failed to drop the table");
       goto err;
     }
+    else
+    {
+      /* Clear the OK result of mysql_rm_table(). */
+      thd->main_da.reset_diagnostics_area();
+    }
+  }
 
   /* Create the table. We do not want to log the "create table" statement */
   save_options = thd->options;
@@ -1012,6 +1019,7 @@ static int create_table_from_dump(THD* thd, MYSQL *mysql, const char* db,
   if (thd->is_slave_error)
     goto err;                   // mysql_parse took care of the error send
 
+  thd->main_da.reset_diagnostics_area(); /* cleanup from CREATE_TABLE */
   thd->proc_info = "Opening master dump table";
   /*
     Note: If this function starts to fail for MERGE tables,
@@ -1055,7 +1063,6 @@ static int create_table_from_dump(THD* thd, MYSQL *mysql, const char* db,
 
 err:
   close_thread_tables(thd);
-  thd->net.no_send_ok = 0;
   DBUG_RETURN(error);
 }
 
@@ -1107,7 +1114,6 @@ int fetch_master_table(THD *thd, const char *db_name, const char *table_name,
   error = 0;
 
  err:
-  thd->net.no_send_ok = 0; // Clear up garbage after create_table_from_dump
   if (!called_connected)
     mysql_close(mysql);
   if (errmsg && thd->vio_ok())
@@ -1721,26 +1727,31 @@ static int has_temporary_error(THD *thd)
   DBUG_ENTER("has_temporary_error");
 
   if (thd->is_fatal_error)
-  {
-    DBUG_PRINT("info", ("thd->net.last_errno: %s", ER(thd->net.last_errno)));
     DBUG_RETURN(0);
-  }
 
   DBUG_EXECUTE_IF("all_errors_are_temporary_errors",
-                  if (thd->net.last_errno)
+                  if (thd->main_da.is_error())
-                    thd->net.last_errno= ER_LOCK_DEADLOCK;);
+                  {
+                    thd->clear_error();
+                    my_error(ER_LOCK_DEADLOCK, MYF(0));
+                  });
+
+  /*
+    If there is no message in THD, we can't say if it's a temporary
+    error or not. This is currently the case for Incident_log_event,
+    which sets no message. Return FALSE.
+  */
+  if (!thd->is_error())
+    DBUG_RETURN(0);
 
   /*
     Temporary error codes:
     currently, InnoDB deadlock detected by InnoDB or lock
     wait timeout (innodb_lock_wait_timeout exceeded
   */
-  if (thd->net.last_errno == ER_LOCK_DEADLOCK ||
+  if (thd->main_da.sql_errno() == ER_LOCK_DEADLOCK ||
-      thd->net.last_errno == ER_LOCK_WAIT_TIMEOUT)
+      thd->main_da.sql_errno() == ER_LOCK_WAIT_TIMEOUT)
-  {
-    DBUG_PRINT("info", ("thd->net.last_errno: %s", ER(thd->net.last_errno)));
     DBUG_RETURN(1);
-  }
 
 #ifdef HAVE_NDB_BINLOG
   /*
@@ -2551,20 +2562,21 @@ Slave SQL thread aborted. Can't execute init_slave query");
         */
         uint32 const last_errno= rli->last_error().number;
 
-        DBUG_PRINT("info", ("thd->net.last_errno=%d; rli->last_error.number=%d",
+        if (thd->is_error())
-                            thd->net.last_errno, last_errno));
-        if (thd->net.last_errno != 0)
         {
-          char const *const errmsg=
+          char const *const errmsg= thd->main_da.message();
-            thd->net.last_error ? thd->net.last_error : "<no message>";
+
+          DBUG_PRINT("info",
+                     ("thd->main_da.sql_errno()=%d; rli->last_error.number=%d",
+                      thd->main_da.sql_errno(), last_errno));
           if (last_errno == 0)
           {
-            rli->report(ERROR_LEVEL, thd->net.last_errno, errmsg);
+            rli->report(ERROR_LEVEL, thd->main_da.sql_errno(), errmsg);
           }
-          else if (last_errno != thd->net.last_errno)
+          else if (last_errno != thd->main_da.sql_errno())
           {
             sql_print_error("Slave (additional info): %s Error_code: %d",
-                            errmsg, thd->net.last_errno);
+                            errmsg, thd->main_da.sql_errno());
           }
         }
 

sql/sp_head.cc

@@ -1202,12 +1202,6 @@ sp_head::execute(THD *thd)
     
     err_status= i->execute(thd, &ip);
 
-    /*
-      If this SP instruction have sent eof, it has caused no_send_error to be
-      set. Clear it back to allow the next instruction to send error. (multi-
-      statement execution code clears no_send_error between statements too)
-    */
-    thd->net.no_send_error= 0;
     if (i->free_list)
       cleanup_items(i->free_list);
     
@@ -2762,14 +2756,22 @@ sp_instr_stmt::execute(THD *thd, uint *nextp)
 					  thd->query, thd->query_length) <= 0)
     {
       res= m_lex_keeper.reset_lex_and_exec_core(thd, nextp, FALSE, this);
+
+      if (thd->main_da.is_eof())
+        net_end_statement(thd);
+
+      query_cache_end_of_result(thd);
+
       if (!res && unlikely(thd->enable_slow_log))
         log_slow_statement(thd);
-      query_cache_end_of_result(thd);
     }
     else
       *nextp= m_ip+1;
     thd->query= query;
     thd->query_length= query_length;
+
+    if (!thd->is_error())
+      thd->main_da.reset_diagnostics_area();
   }
   DBUG_RETURN(res);
 }

sql/sp_rcontext.cc

@@ -287,7 +287,6 @@ sp_rcontext::find_handler(THD *thd, uint sql_errno,
     sql_errno     The error code
     level         Warning level
     thd           The current thread
-                  - thd->net.report_error is an optional output.
 
   RETURN
     TRUE       if a handler was found.
@@ -298,7 +297,6 @@ sp_rcontext::handle_error(uint sql_errno,
                           MYSQL_ERROR::enum_warning_level level,
                           THD *thd)
 {
-  bool handled= FALSE;
   MYSQL_ERROR::enum_warning_level elevated_level= level;
 
 
@@ -310,25 +308,7 @@ sp_rcontext::handle_error(uint sql_errno,
     elevated_level= MYSQL_ERROR::WARN_LEVEL_ERROR;
   }
 
-  if (find_handler(thd, sql_errno, elevated_level))
+  return find_handler(thd, sql_errno, elevated_level);
-  {
-    if (elevated_level == MYSQL_ERROR::WARN_LEVEL_ERROR)
-    {
-      /*
-         Forces to abort the current instruction execution.
-         NOTE: This code is altering the original meaning of
-         the net.report_error flag (send an error to the client).
-         In the context of stored procedures with error handlers,
-         the flag is reused to cause error propagation,
-         until the error handler is reached.
-         No messages will be sent to the client in that context.
-      */
-      thd->net.report_error= 1;
-    }
-    handled= TRUE;
-  }
-
-  return handled;
 }
 
 void

sql/sql_acl.cc

@@ -695,7 +695,7 @@ my_bool acl_reload(THD *thd)
   if (simple_open_n_lock_tables(thd, tables))
   {
     sql_print_error("Fatal error: Can't open and lock privilege tables: %s",
-		    thd->net.last_error);
+		    thd->main_da.message());
     goto end;
   }
 
@@ -3800,11 +3800,11 @@ my_bool grant_reload(THD *thd)
   close_thread_tables(thd);
 
   /*
-    It is ok failing to load procs_priv table because we may be
+    It is OK failing to load procs_priv table because we may be
     working with 4.1 privilege tables.
   */
   if (grant_reload_procs_priv(thd))
-    my_error(ER_CANNOT_LOAD_FROM_TABLE, MYF(0), "mysql.procs_priv");
+    return_val= 1;
 
   rw_wrlock(&LOCK_grant);
   grant_version++;
@@ -5693,9 +5693,6 @@ bool mysql_drop_user(THD *thd, List <LEX_USER> &list)
   if (result)
     my_error(ER_CANNOT_USER, MYF(0), "DROP USER", wrong_users.c_ptr_safe());
 
-  DBUG_PRINT("info", ("thd->net.last_errno: %d", thd->net.last_errno));
-  DBUG_PRINT("info", ("thd->net.last_error: %s", thd->net.last_error));
-
   write_bin_log(thd, FALSE, thd->query, thd->query_length);
 
   rw_unlock(&LOCK_grant);

sql/sql_base.cc

@@ -491,9 +491,28 @@ static TABLE_SHARE
   int tmp;
   DBUG_ENTER("get_table_share_with_create");
 
-  if ((share= get_table_share(thd, table_list, key, key_length, 
+  share= get_table_share(thd, table_list, key, key_length, db_flags, error);
-                              db_flags, error)) ||
+  /*
-      thd->net.last_errno != ER_NO_SUCH_TABLE)
+    If share is not NULL, we found an existing share.
+
+    If share is NULL, and there is no error, we're inside
+    pre-locking, which silences 'ER_NO_SUCH_TABLE' errors
+    with the intention to silently drop non-existing tables 
+    from the pre-locking list. In this case we still need to try
+    auto-discover before returning a NULL share.
+
+    If share is NULL and the error is ER_NO_SUCH_TABLE, this is
+    the same as above, only that the error was not silenced by 
+    pre-locking. Once again, we need to try to auto-discover
+    the share.
+
+    Finally, if share is still NULL, it's a real error and we need
+    to abort.
+
+    @todo Rework alternative ways to deal with ER_NO_SUCH TABLE.
+  */
+  if (share || thd->is_error() && thd->main_da.sql_errno() != ER_NO_SUCH_TABLE)
+
     DBUG_RETURN(share);
 
   /* Table didn't exist. Check if some engine can provide it */
@@ -502,9 +521,13 @@ static TABLE_SHARE
   {
     /*
       No such table in any engine.
-      Hide "Table doesn't exist" errors if table belong to view
+      Hide "Table doesn't exist" errors if the table belongs to a view.
+      The check for thd->is_error() is necessary to not push an
+      unwanted error in case of pre-locking, which silences
+      "no such table" errors.
+      @todo Rework the alternative ways to deal with ER_NO_SUCH TABLE.
     */
-    if (table_list->belong_to_view)
+    if (thd->is_error() && table_list->belong_to_view)
     {
       TABLE_LIST *view= table_list->belong_to_view;
       thd->clear_error();

sql/sql_binlog.cc

@@ -40,13 +40,6 @@ void mysql_client_binlog_statement(THD* thd)
   if (check_global_access(thd, SUPER_ACL))
     DBUG_VOID_RETURN;
 
-  /*
-    Temporarily turn off send_ok, since different events handle this
-    differently
-  */
-  my_bool nsok= thd->net.no_send_ok;
-  thd->net.no_send_ok= TRUE;
-
   size_t coded_len= thd->lex->comment.length + 1;
   size_t decoded_len= base64_needed_decoded_length(coded_len);
   DBUG_ASSERT(coded_len > 0);
@@ -193,20 +186,11 @@ void mysql_client_binlog_statement(THD* thd)
     }
   }
 
-  /*
-    Restore setting of no_send_ok
-  */
-  thd->net.no_send_ok= nsok;
 
   DBUG_PRINT("info",("binlog base64 execution finished successfully"));
   send_ok(thd);
 
 end:
-  /*
-    Restore setting of no_send_ok
-  */
-  thd->net.no_send_ok= nsok;
-
   delete desc;
   my_free(buf, MYF(MY_ALLOW_ZERO_PTR));
   DBUG_VOID_RETURN;

sql/sql_cache.cc

@@ -1403,6 +1403,7 @@ def_week_frmt: %lu",
 
   thd->limit_found_rows = query->found_rows();
   thd->status_var.last_query_cost= 0.0;
+  thd->main_da.disable_status();
 
   BLOCK_UNLOCK_RD(query_block);
   DBUG_RETURN(1);				// Result sent to client

sql/sql_class.cc

@@ -351,6 +351,124 @@ char *thd_security_context(THD *thd, char *buffer, unsigned int length,
   return thd->strmake(str.ptr(), str.length());
 }
 
+/**
+  Clear this diagnostics area. 
+
+  Normally called at the end of a statement.
+*/
+
+void
+Diagnostics_area::reset_diagnostics_area()
+{
+#ifdef DBUG_OFF
+  can_overwrite_status= FALSE;
+  /** Don't take chances in production */
+  m_message[0]= '\0';
+  m_sql_errno= 0;
+  m_server_status= 0;
+  m_affected_rows= 0;
+  m_last_insert_id= 0;
+  m_total_warn_count= 0;
+#endif
+  is_sent= FALSE;
+  /** Tiny reset in debug mode to see garbage right away */
+  m_status= DA_EMPTY;
+}
+
+
+/**
+  Set OK status -- ends commands that do not return a
+  result set, e.g. INSERT/UPDATE/DELETE.
+*/
+
+void
+Diagnostics_area::set_ok_status(THD *thd, ha_rows affected_rows_arg,
+                                ulong last_insert_id_arg,
+                                const char *message_arg)
+{
+  DBUG_ASSERT(! is_set());
+#ifdef DBUG_OFF
+  /* In production, refuse to overwrite an error with an OK packet. */
+  if (is_error())
+    return;
+#endif
+  /** Only allowed to report success if has not yet reported an error */
+
+  m_server_status= thd->server_status;
+  m_total_warn_count= thd->total_warn_count;
+  m_affected_rows= affected_rows_arg;
+  m_last_insert_id= last_insert_id_arg;
+  if (message_arg)
+    strmake(m_message, message_arg, sizeof(m_message));
+  else
+    m_message[0]= '\0';
+  m_status= DA_OK;
+}
+
+
+/**
+  Set EOF status.
+*/
+
+void
+Diagnostics_area::set_eof_status(THD *thd)
+{
+  /** Only allowed to report eof if has not yet reported an error */
+
+  DBUG_ASSERT(! is_set());
+#ifdef DBUG_OFF
+  /* In production, refuse to overwrite an error with an EOF packet. */
+  if (is_error())
+    return;
+#endif
+
+  m_server_status= thd->server_status;
+  /*
+    If inside a stored procedure, do not return the total
+    number of warnings, since they are not available to the client
+    anyway.
+  */
+  m_total_warn_count= thd->spcont ? 0 : thd->total_warn_count;
+
+  m_status= DA_EOF;
+}
+
+/**
+  Set ERROR status.
+*/
+
+void
+Diagnostics_area::set_error_status(THD *thd, uint sql_errno_arg,
+                                   const char *message_arg)
+{
+  /*
+    Only allowed to report error if has not yet reported a success
+    The only exception is when we flush the message to the client,
+    an error can happen during the flush.
+  */
+  DBUG_ASSERT(! is_set() || can_overwrite_status);
+
+  m_sql_errno= sql_errno_arg;
+  strmake(m_message, message_arg, sizeof(m_message));
+
+  m_status= DA_ERROR;
+}
+
+
+/**
+  Mark the diagnostics area as 'DISABLED'.
+
+  This is used in rare cases when the COM_ command at hand sends a response
+  in a custom format. One example is the query cache, another is
+  COM_STMT_PREPARE.
+*/
+
+void
+Diagnostics_area::disable_status()
+{
+  DBUG_ASSERT(! is_set());
+  m_status= DA_DISABLED;
+}
 
 
 THD::THD()
@@ -431,7 +549,6 @@ THD::THD()
   net.vio=0;
 #endif
   client_capabilities= 0;                       // minimalistic client
-  net.last_error[0]=0;                          // If error on boot
 #ifdef HAVE_QUERY_CACHE
   query_cache_init_query(&net);                 // If error on boot
 #endif
@@ -1324,12 +1441,12 @@ void select_send::abort()
 {
   DBUG_ENTER("select_send::abort");
   if (is_result_set_started && thd->spcont &&
-      thd->spcont->find_handler(thd, thd->net.last_errno,
+      thd->spcont->find_handler(thd, thd->main_da.sql_errno(),
                                 MYSQL_ERROR::WARN_LEVEL_ERROR))
   {
     /*
       We're executing a stored procedure, have an open result
-      set, an SQL exception conditiona and a handler for it.
+      set, an SQL exception condition and a handler for it.
       In this situation we must abort the current statement,
       silence the error and start executing the continue/exit
       handler.
@@ -1337,9 +1454,7 @@ void select_send::abort()
       otherwise the client will hang due to the violation of the
       client/server protocol.
     */
-    thd->net.report_error= 0;
+    thd->protocol->end_partial_result_set(thd);
-    send_eof();
-    thd->net.report_error= 1; // Abort SP
   }
   DBUG_VOID_RETURN;
 }
@@ -1391,12 +1506,14 @@ bool select_send::send_data(List<Item> &items)
     }
   }
   thd->sent_row_count++;
-  if (!thd->vio_ok())
+  if (thd->is_error())
-    DBUG_RETURN(0);
+  {
-  if (! thd->is_error())
-    DBUG_RETURN(protocol->write());
     protocol->remove_last_row();
     DBUG_RETURN(1);
+  }
+  if (thd->vio_ok())
+    DBUG_RETURN(protocol->write());
+  DBUG_RETURN(0);
 }
 
 bool select_send::send_eof()
@@ -1414,14 +1531,9 @@ bool select_send::send_eof()
     mysql_unlock_tables(thd, thd->lock);
     thd->lock=0;
   }
-  if (! thd->is_error())
-  {
   ::send_eof(thd);
   is_result_set_started= 0;
-    return 0;
+  return FALSE;
-  }
-  else
-    return 1;
 }
 
 
@@ -2701,7 +2813,6 @@ void THD::reset_sub_statement_state(Sub_statement_state *backup,
 {
   backup->options=         options;
   backup->in_sub_stmt=     in_sub_stmt;
-  backup->no_send_ok=      net.no_send_ok;
   backup->enable_slow_log= enable_slow_log;
   backup->limit_found_rows= limit_found_rows;
   backup->examined_row_count= examined_row_count;
@@ -2732,9 +2843,6 @@ void THD::reset_sub_statement_state(Sub_statement_state *backup,
   cuted_fields= 0;
   transaction.savepoints= 0;
   first_successful_insert_id_in_cur_stmt= 0;
-
-  /* Surpress OK packets in case if we will execute statements */
-  net.no_send_ok= TRUE;
 }
 
 
@@ -2757,7 +2865,6 @@ void THD::restore_sub_statement_state(Sub_statement_state *backup)
   transaction.savepoints= backup->savepoints;
   options=          backup->options;
   in_sub_stmt=      backup->in_sub_stmt;
-  net.no_send_ok=   backup->no_send_ok;
   enable_slow_log=  backup->enable_slow_log;
   first_successful_insert_id_in_prev_stmt= 
     backup->first_successful_insert_id_in_prev_stmt;

sql/sql_class.h

@@ -913,7 +913,6 @@ public:
   uint in_sub_stmt;
   bool enable_slow_log;
   bool last_insert_id_used;
-  my_bool no_send_ok;
   SAVEPOINT *savepoints;
 };
 
@@ -975,6 +974,123 @@ public:
 };
 
 
+/**
+  Stores status of the currently executed statement.
+  Cleared at the beginning of the statement, and then
+  can hold either OK, ERROR, or EOF status.
+  Can not be assigned twice per statement.
+*/
+
+class Diagnostics_area
+{
+public:
+  enum enum_diagnostics_status
+  {
+    /** The area is cleared at start of a statement. */
+    DA_EMPTY= 0,
+    /** Set whenever one calls send_ok(). */
+    DA_OK,
+    /** Set whenever one calls send_eof(). */
+    DA_EOF,
+    /** Set whenever one calls my_error() or my_message(). */
+    DA_ERROR,
+    /** Set in case of a custom response, such as one from COM_STMT_PREPARE. */
+    DA_DISABLED
+  };
+  /** True if status information is sent to the client. */
+  bool is_sent;
+  /** Set to make set_error_status after set_{ok,eof}_status possible. */
+  bool can_overwrite_status;
+
+  void set_ok_status(THD *thd, ha_rows affected_rows_arg,
+                     ulong last_insert_id_arg,
+                     const char *message);
+  void set_eof_status(THD *thd);
+  void set_error_status(THD *thd, uint sql_errno_arg, const char *message_arg);
+
+  void disable_status();
+
+  void reset_diagnostics_area();
+
+  bool is_set() const { return m_status != DA_EMPTY; }
+  bool is_error() const { return m_status == DA_ERROR; }
+  bool is_eof() const { return m_status == DA_EOF; }
+  bool is_ok() const { return m_status == DA_OK; }
+  bool is_disabled() const { return m_status == DA_DISABLED; }
+  enum_diagnostics_status status() const { return m_status; }
+
+  const char *message() const
+  { DBUG_ASSERT(m_status == DA_ERROR || m_status == DA_OK); return m_message; }
+
+  uint sql_errno() const
+  { DBUG_ASSERT(m_status == DA_ERROR); return m_sql_errno; }
+
+  uint server_status() const
+  {
+    DBUG_ASSERT(m_status == DA_OK || m_status == DA_EOF);
+    return m_server_status;
+  }
+
+  ha_rows affected_rows() const
+  { DBUG_ASSERT(m_status == DA_OK); return m_affected_rows; }
+
+  ulong last_insert_id() const
+  { DBUG_ASSERT(m_status == DA_OK); return m_last_insert_id; }
+
+  uint total_warn_count() const
+  {
+    DBUG_ASSERT(m_status == DA_OK || m_status == DA_EOF);
+    return m_total_warn_count;
+  }
+
+  Diagnostics_area() { reset_diagnostics_area(); }
+
+private:
+  /** Message buffer. Can be used by OK or ERROR status. */
+  char m_message[MYSQL_ERRMSG_SIZE];
+  /**
+    SQL error number. One of ER_ codes from share/errmsg.txt.
+    Set by set_error_status.
+  */
+  uint m_sql_errno;
+
+  /**
+    Copied from thd->server_status when the diagnostics area is assigned.
+    We need this member as some places in the code use the following pattern:
+    thd->server_status|= ...
+    send_eof(thd);
+    thd->server_status&= ~...
+    Assigned by OK, EOF or ERROR.
+  */
+  uint m_server_status;
+  /**
+    The number of rows affected by the last statement. This is
+    semantically close to thd->row_count_func, but has a different
+    life cycle. thd->row_count_func stores the value returned by
+    function ROW_COUNT() and is cleared only by statements that
+    update its value, such as INSERT, UPDATE, DELETE and few others.
+    This member is cleared at the beginning of the next statement.
+
+    We could possibly merge the two, but life cycle of thd->row_count_func
+    can not be changed.
+  */
+  ha_rows    m_affected_rows;
+  /**
+    Similarly to the previous member, this is a replacement of
+    thd->first_successful_insert_id_in_prev_stmt, which is used
+    to implement LAST_INSERT_ID().
+  */
+  ulong      m_last_insert_id;
+  /** The total number of warnings. */
+  uint	     m_total_warn_count;
+  enum_diagnostics_status m_status;
+  /**
+    @todo: the following THD members belong here:
+    - warn_list, warn_count,
+  */
+};
+
+
 /**
   @class THD
   For each client connection we create a separate thread with THD serving as
@@ -1400,6 +1516,7 @@ public:
   List	     <MYSQL_ERROR> warn_list;
   uint	     warn_count[(uint) MYSQL_ERROR::WARN_LEVEL_END];
   uint	     total_warn_count;
+  Diagnostics_area main_da;
   /*
     Id of current query. Statement can be reused to execute several queries
     query_id is global in context of the whole MySQL server.
@@ -1714,12 +1831,18 @@ public:
   CHANGED_TABLE_LIST * changed_table_dup(const char *key, long key_length);
   int send_explain_fields(select_result *result);
 #ifndef EMBEDDED_LIBRARY
+  /**
+    Clear the current error, if any.
+    We do not clear is_fatal_error or is_fatal_sub_stmt_error since we
+    assume this is never called if the fatal error is set.
+    @todo: To silence an error, one should use Internal_error_handler
+    mechanism. In future this function will be removed.
+  */
   inline void clear_error()
   {
     DBUG_ENTER("clear_error");
-    net.last_error[0]= 0;
+    if (main_da.is_error())
-    net.last_errno= 0;
+      main_da.reset_diagnostics_area();
-    net.report_error= 0;
     is_slave_error= 0;
     DBUG_VOID_RETURN;
   }
@@ -1728,10 +1851,14 @@ public:
   void clear_error();
   inline bool vio_ok() const { return true; }
 #endif
+  /**
+    Mark the current error as fatal. Warning: this does not
+    set any error, it sets a property of the error, so must be
+    followed or prefixed with my_error().
+  */
   inline void fatal_error()
   {
     is_fatal_error= 1;
-    net.report_error= 1;
     DBUG_PRINT("error",("Fatal error set"));
   }
   /**
@@ -1747,7 +1874,7 @@ public:
 
     To raise this flag, use my_error().
   */
-  inline bool is_error() const { return net.report_error; }
+  inline bool is_error() const { return main_da.is_error(); }
   inline CHARSET_INFO *charset() { return variables.character_set_client; }
   void update_charset();
 
@@ -1971,6 +2098,24 @@ private:
 };
 
 
+/** A short cut for thd->main_da.set_ok_status(). */
+
+inline void
+send_ok(THD *thd, ha_rows affected_rows= 0, ulonglong id= 0,
+        const char *message= NULL)
+{
+  thd->main_da.set_ok_status(thd, affected_rows, id, message);
+}
+
+
+/** A short cut for thd->main_da.set_eof_status(). */
+
+inline void
+send_eof(THD *thd)
+{
+  thd->main_da.set_eof_status(thd);
+}
+
 #define tmp_disable_binlog(A)       \
   {ulonglong tmp_disable_binlog__save_options= (A)->options; \
   (A)->options&= ~OPTION_BIN_LOG
@@ -2508,6 +2653,7 @@ public:
   void send_error(uint errcode,const char *err);
   int  do_deletes();
   bool send_eof();
+  virtual void abort();
 };
 
 
@@ -2550,6 +2696,7 @@ public:
   void send_error(uint errcode,const char *err);
   int  do_updates (bool from_send_error);
   bool send_eof();
+  virtual void abort();
 };
 
 class my_var : public Sql_alloc  {

sql/sql_connect.cc

@@ -948,19 +948,20 @@ bool setup_connection_thread_globals(THD *thd)
 bool login_connection(THD *thd)
 {
   NET *net= &thd->net;
+  int error;
   DBUG_ENTER("login_connection");
   DBUG_PRINT("info", ("login_connection called by thread %lu",
                       thd->thread_id));
 
-  net->no_send_error= 0;
-
   /* Use "connect_timeout" value during connection phase */
   my_net_set_read_timeout(net, connect_timeout);
   my_net_set_write_timeout(net, connect_timeout);
 
-  if (check_connection(thd))
+  error= check_connection(thd);
+  net_end_statement(thd);
+
+  if (error)
   {						// Wrong permissions
-    net_send_error(thd);
 #ifdef __NT__
     if (vio_type(net->vio) == VIO_TYPE_NAMEDPIPE)
       my_sleep(1000);				/* must wait after eof() */
@@ -989,13 +990,12 @@ void end_connection(THD *thd)
   if (thd->user_connect)
     decrease_user_connections(thd->user_connect);
 
-  if (thd->killed ||
+  if (thd->killed || net->error && net->vio != 0)
-      net->error && net->vio != 0 && thd->is_error())
   {
     statistic_increment(aborted_threads,&LOCK_status);
   }
 
-  if (net->error && net->vio != 0 && thd->is_error())
+  if (net->error && net->vio != 0)
   {
     if (!thd->killed && thd->variables.log_warnings > 1)
     {
@@ -1005,11 +1005,9 @@ void end_connection(THD *thd)
                         thd->thread_id,(thd->db ? thd->db : "unconnected"),
                         sctx->user ? sctx->user : "unauthenticated",
                         sctx->host_or_ip,
-                        (net->last_errno ? ER(net->last_errno) :
+                        (thd->main_da.is_error() ? thd->main_da.message() :
                          ER(ER_UNKNOWN_ERROR)));
     }
-
-    net_send_error(thd, net->last_errno, NullS);
   }
 }
 
@@ -1045,24 +1043,14 @@ static void prepare_new_connection_state(THD* thd)
   if (sys_init_connect.value_length && !(sctx->master_access & SUPER_ACL))
   {
     execute_init_command(thd, &sys_init_connect, &LOCK_sys_init_connect);
-    /*
+    if (thd->is_error())
-      execute_init_command calls net_send_error.
-      If there was an error during execution of the init statements, 
-      the error at this moment is present in thd->net.last_error and also
-      thd->is_slave_error and thd->net.report_error are set.
-      net_send_error sends the contents of thd->net.last_error and
-      clears thd->net.report_error. It doesn't, however, clean
-      thd->is_slave_error or thd->net.last_error. Here we make use of this
-      fact.
-    */
-    if (thd->is_slave_error)
     {
       thd->killed= THD::KILL_CONNECTION;
       sql_print_warning(ER(ER_NEW_ABORTING_CONNECTION),
                         thd->thread_id,(thd->db ? thd->db : "unconnected"),
                         sctx->user ? sctx->user : "unauthenticated",
                         sctx->host_or_ip, "init_connect command failed");
-      sql_print_warning("%s", thd->net.last_error);
+      sql_print_warning("%s", thd->main_da.message());
     }
     thd->proc_info=0;
     thd->set_time();
@@ -1129,7 +1117,6 @@ pthread_handler_t handle_one_connection(void *arg)
     while (!net->error && net->vio != 0 &&
            !(thd->killed == THD::KILL_CONNECTION))
     {
-      net->no_send_error= 0;
       if (do_command(thd))
 	break;
     }

sql/sql_db.cc

@@ -921,6 +921,8 @@ bool mysql_rm_db(THD *thd,char *db,bool if_exists, bool silent)
     {
       ha_drop_database(path);
       query_cache_invalidate1(db);
+      (void) sp_drop_db_routines(thd, db); /* @todo Do not ignore errors */
+      Events::drop_schema_events(thd, db);
       error = 0;
     }
   }
@@ -956,6 +958,7 @@ bool mysql_rm_db(THD *thd,char *db,bool if_exists, bool silent)
       /* These DDL methods and logging protected with LOCK_mysql_create_db */
       mysql_bin_log.write(&qinfo);
     }
+    thd->clear_error();
     thd->server_status|= SERVER_STATUS_DB_DROPPED;
     send_ok(thd, (ulong) deleted);
     thd->server_status&= ~SERVER_STATUS_DB_DROPPED;
@@ -999,8 +1002,6 @@ bool mysql_rm_db(THD *thd,char *db,bool if_exists, bool silent)
   }
 
 exit:
-  (void)sp_drop_db_routines(thd, db); /* QQ Ignore errors for now  */
-  Events::drop_schema_events(thd, db);
   /*
     If this database was the client's selected database, we silently
     change the client's selected database to nothing (to have an empty

sql/sql_delete.cc

@@ -728,6 +728,14 @@ void multi_delete::send_error(uint errcode,const char *err)
   /* First send error what ever it is ... */
   my_message(errcode, err, MYF(0));
 
+  DBUG_VOID_RETURN;
+}
+
+
+void multi_delete::abort()
+{
+  DBUG_ENTER("multi_delete::abort");
+
   /* the error was handled or nothing deleted and no side effects return */
   if (error_handled ||
       !thd->transaction.stmt.modified_non_trans_table && !deleted)

sql/sql_derived.cc

@@ -147,8 +147,9 @@ exit:
     /* Hide "Unknown column" or "Unknown function" error */
     if (orig_table_list->view)
     {
-      if (thd->net.last_errno == ER_BAD_FIELD_ERROR ||
+      if (thd->is_error() &&
-          thd->net.last_errno == ER_SP_DOES_NOT_EXIST)
+          (thd->main_da.sql_errno() == ER_BAD_FIELD_ERROR ||
+          thd->main_da.sql_errno() == ER_SP_DOES_NOT_EXIST))
       {
         thd->clear_error();
         my_error(ER_VIEW_INVALID, MYF(0), orig_table_list->db,

sql/sql_insert.cc

@@ -1916,7 +1916,7 @@ bool delayed_get_table(THD *thd, TABLE_LIST *table_list)
             main thread. Use of my_message will enable stored
             procedures continue handlers.
           */
-          my_message(di->thd.net.last_errno, di->thd.net.last_error,
+          my_message(di->thd.main_da.sql_errno(), di->thd.main_da.message(),
                      MYF(0));
 	}
 	di->unlock();
@@ -1993,7 +1993,7 @@ TABLE *Delayed_insert::get_local_table(THD* client_thd)
       goto error;
     if (dead)
     {
-      my_message(thd.net.last_errno, thd.net.last_error, MYF(0));
+      my_message(thd.main_da.sql_errno(), thd.main_da.message(), MYF(0));
       goto error;
     }
   }
@@ -2252,7 +2252,9 @@ pthread_handler_t handle_delayed_insert(void *arg)
 #if !defined( __WIN__) /* Win32 calls this in pthread_create */
   if (my_thread_init())
   {
-    strmov(thd->net.last_error,ER(thd->net.last_errno=ER_OUT_OF_RESOURCES));
+    /* Can't use my_error since store_globals has not yet been called */
+    thd->main_da.set_error_status(thd, ER_OUT_OF_RESOURCES,
+                                  ER(ER_OUT_OF_RESOURCES));
     goto end;
   }
 #endif
@@ -2261,8 +2263,10 @@ pthread_handler_t handle_delayed_insert(void *arg)
   thd->thread_stack= (char*) &thd;
   if (init_thr_lock() || thd->store_globals())
   {
+    /* Can't use my_error since store_globals has perhaps failed */
+    thd->main_da.set_error_status(thd, ER_OUT_OF_RESOURCES,
+                                  ER(ER_OUT_OF_RESOURCES));
     thd->fatal_error();
-    strmov(thd->net.last_error,ER(thd->net.last_errno=ER_OUT_OF_RESOURCES));
     goto err;
   }
 
@@ -2665,7 +2669,7 @@ bool Delayed_insert::handle_inserts(void)
 	{
 	  /* This should never happen */
 	  table->file->print_error(error,MYF(0));
-	  sql_print_error("%s",thd.net.last_error);
+	  sql_print_error("%s", thd.main_da.message());
           DBUG_PRINT("error", ("HA_EXTRA_NO_CACHE failed in loop"));
 	  goto err;
 	}
@@ -2706,7 +2710,7 @@ bool Delayed_insert::handle_inserts(void)
   if ((error=table->file->extra(HA_EXTRA_NO_CACHE)))
   {						// This shouldn't happen
     table->file->print_error(error,MYF(0));
-    sql_print_error("%s",thd.net.last_error);
+    sql_print_error("%s", thd.main_da.message());
     DBUG_PRINT("error", ("HA_EXTRA_NO_CACHE failed after loop"));
     goto err;
   }

sql/sql_parse.cc

@@ -328,7 +328,6 @@ void execute_init_command(THD *thd, sys_var_str *init_command_var,
   */
   save_vio= thd->net.vio;
   thd->net.vio= 0;
-  thd->net.no_send_error= 0;
   dispatch_command(COM_QUERY, thd,
                    init_command_var->value,
                    init_command_var->value_length);
@@ -397,8 +396,8 @@ pthread_handler_t handle_bootstrap(void *arg)
       /* purecov: begin tested */
       if (net_realloc(&(thd->net), 2 * thd->net.max_packet))
       {
-        net_send_error(thd, ER_NET_PACKET_TOO_LARGE, NullS);
+        net_end_statement(thd);
-        thd->fatal_error();
+        bootstrap_error= 1;
         break;
       }
       buff= (char*) thd->net.buff;
@@ -406,7 +405,7 @@ pthread_handler_t handle_bootstrap(void *arg)
       length+= (ulong) strlen(buff + length);
       /* purecov: end */
     }
-    if (thd->is_fatal_error)
+    if (bootstrap_error)
       break;                                    /* purecov: inspected */
 
     while (length && (my_isspace(thd->charset(), buff[length-1]) ||
@@ -433,16 +432,11 @@ pthread_handler_t handle_bootstrap(void *arg)
     mysql_parse(thd, thd->query, length, & found_semicolon);
     close_thread_tables(thd);			// Free tables
 
-    if (thd->is_fatal_error)
+    bootstrap_error= thd->is_error();
-      break;
+    net_end_statement(thd);
 
-    if (thd->is_error())
+    if (bootstrap_error)
-    {
-      /* The query failed, send error to log and abort bootstrap */
-      net_send_error(thd);
-      thd->fatal_error();
       break;
-    }
 
     free_root(thd->mem_root,MYF(MY_KEEP_PREALLOC));
 #ifdef USING_TRANSACTIONS
@@ -451,9 +445,6 @@ pthread_handler_t handle_bootstrap(void *arg)
   }
 
 end:
-  /* Remember the exit code of bootstrap */
-  bootstrap_error= thd->is_fatal_error;
-
   net_end(&thd->net);
   thd->cleanup();
   delete thd;
@@ -712,7 +703,12 @@ bool do_command(THD *thd)
   */
   my_net_set_read_timeout(net, thd->variables.net_wait_timeout);
 
+  /*
+    XXX: this code is here only to clear possible errors of init_connect. 
+    Consider moving to init_connect() instead.
+  */
   thd->clear_error();				// Clear error message
+  thd->main_da.reset_diagnostics_area();
 
   net_new_transaction(net);
   if ((packet_length=my_net_read(net)) == packet_error)
@@ -723,10 +719,13 @@ bool do_command(THD *thd)
 
     /* Check if we can continue without closing the connection */
 
+    /* The error must be set. */
+    DBUG_ASSERT(thd->is_error());
+    net_end_statement(thd);
+
     if (net->error != 3)
       DBUG_RETURN(TRUE);			// We have to close it.
 
-    net_send_error(thd, net->last_errno, NullS);
     net->error= 0;
     DBUG_RETURN(FALSE);
   }
@@ -860,7 +859,8 @@ bool dispatch_command(enum enum_server_command command, THD *thd,
     db.length= db_len;
     tbl_name= strmake(db.str, packet + 1, db_len)+1;
     strmake(tbl_name, packet + db_len + 2, tbl_len);
-    mysql_table_dump(thd, &db, tbl_name);
+    if (mysql_table_dump(thd, &db, tbl_name) == 0)
+      thd->main_da.disable_status();
     break;
   }
   case COM_CHANGE_USER:
@@ -1024,7 +1024,9 @@ bool dispatch_command(enum enum_server_command command, THD *thd,
     while (!thd->killed && found_semicolon && ! thd->is_error())
     {
       char *next_packet= (char*) found_semicolon;
-      net->no_send_error= 0;
+
+      net_end_statement(thd);
+      query_cache_end_of_result(thd);
       /*
         Multiple queries exits, execute them individually
       */
@@ -1125,6 +1127,7 @@ bool dispatch_command(enum enum_server_command command, THD *thd,
     /* We don't calculate statistics for this command */
     general_log_print(thd, command, NullS);
     net->error=0;				// Don't give 'abort' message
+    thd->main_da.disable_status();              // Don't send anything back
     error=TRUE;					// End server
     break;
 
@@ -1241,16 +1244,6 @@ bool dispatch_command(enum enum_server_command command, THD *thd,
     DBUG_PRINT("quit",("Got shutdown command for level %u", level));
     general_log_print(thd, command, NullS);
     send_eof(thd);
-#ifdef __WIN__
-    sleep(1);					// must wait after eof()
-#endif
-    /*
-      The client is next going to send a COM_QUIT request (as part of
-      mysql_close()). Make the life simpler for the client by sending
-      the response for the coming COM_QUIT in advance
-    */
-    send_eof(thd);
-    close_connection(thd, 0, 1);
     close_thread_tables(thd);			// Free before kill
     kill_mysql();
     error=TRUE;
@@ -1263,13 +1256,8 @@ bool dispatch_command(enum enum_server_command command, THD *thd,
     ulong uptime;
     uint length;
     ulonglong queries_per_second1000;
-#ifndef EMBEDDED_LIBRARY
     char buff[250];
     uint buff_len= sizeof(buff);
-#else
-    char *buff= thd->net.last_error;
-    uint buff_len= sizeof(thd->net.last_error);
-#endif
 
     general_log_print(thd, command, NullS);
     status_var_increment(thd->status_var.com_stat[SQLCOM_SHOW_STATUS]);
@@ -1291,6 +1279,10 @@ bool dispatch_command(enum enum_server_command command, THD *thd,
                         cached_open_tables(),
                         (uint) (queries_per_second1000 / 1000),
                         (uint) (queries_per_second1000 % 1000));
+#ifdef EMBEDDED_LIBRARY
+    /* Store the buffer in permanent memory */
+    send_ok(thd, 0, 0, buff);
+#endif
 #ifdef SAFEMALLOC
     if (sf_malloc_cur_memory)				// Using SAFEMALLOC
     {
@@ -1304,6 +1296,7 @@ bool dispatch_command(enum enum_server_command command, THD *thd,
 #ifndef EMBEDDED_LIBRARY
     VOID(my_net_write(net, (uchar*) buff, length));
     VOID(net_flush(net));
+    thd->main_da.disable_status();
 #endif
     break;
   }
@@ -1383,10 +1376,19 @@ bool dispatch_command(enum enum_server_command command, THD *thd,
     thd->transaction.xid_state.xid.null();
 
   /* report error issued during command execution */
-  if (thd->killed_errno() && ! thd->is_error())
+  if (thd->killed_errno())
+  {
+    if (! thd->main_da.is_set())
       thd->send_kill_message();
-  if (thd->is_error())
+  }
-    net_send_error(thd);
+  if (thd->killed == THD::KILL_QUERY || thd->killed == THD::KILL_BAD_DATA)
+  {
+    thd->killed= THD::NOT_KILLED;
+    thd->mysys_var->abort= 0;
+  }
+
+  net_end_statement(thd);
+  query_cache_end_of_result(thd);
 
   log_slow_statement(thd);
 
@@ -1756,7 +1758,6 @@ mysql_execute_command(THD *thd)
   SELECT_LEX_UNIT *unit= &lex->unit;
   /* Saved variable value */
   DBUG_ENTER("mysql_execute_command");
-  thd->net.no_send_error= 0;
 #ifdef WITH_PARTITION_STORAGE_ENGINE
   thd->work_part_info= 0;
 #endif
@@ -2992,13 +2993,9 @@ end_with_restore_list:
 			SELECT_NO_JOIN_CACHE | SELECT_NO_UNLOCK |
                         OPTION_SETUP_TABLES_DONE,
 			del_result, unit, select_lex);
-      res|= thd->net.report_error;
+      res|= thd->is_error();
-      if (unlikely(res))
+      if (res)
-      {
-        /* If we had a another error reported earlier then this will be ignored */
-        del_result->send_error(ER_UNKNOWN_ERROR, "Execution of the query failed");
         del_result->abort();
-      }
       delete del_result;
     }
     else
@@ -3931,8 +3928,6 @@ create_sp_error:
             goto error;
         }
 
-	my_bool save_no_send_ok= thd->net.no_send_ok;
-	thd->net.no_send_ok= TRUE;
 	if (sp->m_flags & sp_head::MULTI_RESULTS)
 	{
 	  if (! (thd->client_capabilities & CLIENT_MULTI_RESULTS))
@@ -3942,7 +3937,6 @@ create_sp_error:
               back
             */
 	    my_error(ER_SP_BADSELECT, MYF(0), sp->m_qname.str);
-	    thd->net.no_send_ok= save_no_send_ok;
 	    goto error;
 	  }
           /*
@@ -3958,7 +3952,6 @@ create_sp_error:
 	if (check_routine_access(thd, EXECUTE_ACL,
 				 sp->m_db.str, sp->m_name.str, TRUE, FALSE))
 	{
-	  thd->net.no_send_ok= save_no_send_ok;
 	  goto error;
 	}
 #endif
@@ -3983,7 +3976,6 @@ create_sp_error:
 
 	thd->variables.select_limit= select_limit;
 
-	thd->net.no_send_ok= save_no_send_ok;
         thd->server_status&= ~bits_to_be_cleared;
 
 	if (!res)
@@ -4624,6 +4616,9 @@ static bool execute_sqlcom_select(THD *thd, TABLE_LIST *all_tables)
         push_warning(thd, MYSQL_ERROR::WARN_LEVEL_NOTE,
                      ER_YES, str.ptr());
       }
+      if (res)
+        result->abort();
+      else
         result->send_eof();
       delete result;
     }
@@ -5251,6 +5246,7 @@ void mysql_reset_thd_for_next_command(THD *thd)
 {
   DBUG_ENTER("mysql_reset_thd_for_next_command");
   DBUG_ASSERT(!thd->spcont); /* not for substatements of routines */
+  DBUG_ASSERT(! thd->in_sub_stmt);
   thd->free_list= 0;
   thd->select_number= 1;
   /*
@@ -5277,18 +5273,18 @@ void mysql_reset_thd_for_next_command(THD *thd)
   }
   DBUG_ASSERT(thd->security_ctx== &thd->main_security_ctx);
   thd->thread_specific_used= FALSE;
-  if (!thd->in_sub_stmt)
+
-  {
   if (opt_bin_log)
   {
     reset_dynamic(&thd->user_var_events);
     thd->user_var_events_alloc= thd->mem_root;
   }
   thd->clear_error();
+  thd->main_da.reset_diagnostics_area();
   thd->total_warn_count=0;			// Warnings for this query
   thd->rand_used= 0;
   thd->sent_row_count= thd->examined_row_count= 0;
-  }
+
   /*
     Because we come here only for start of top-statements, binlog format is
     constant inside a complex statement (using stored functions) etc.
@@ -5526,7 +5522,6 @@ void mysql_parse(THD *thd, const char *inBuf, uint length,
           /* Actually execute the query */
           lex->set_trg_event_type_for_tables();
           mysql_execute_command(thd);
-          query_cache_end_of_result(thd);
 	}
       }
     }
@@ -6378,8 +6373,10 @@ bool reload_acl_and_cache(THD *thd, ulong options, TABLE_LIST *tables,
     }
     if (thd)
     {
-      (void)acl_reload(thd);
+      if (acl_reload(thd))
-      (void)grant_reload(thd);
+        result= 1;
+      if (grant_reload(thd))
+        result= 1;
     }
     if (tmp_thd)
     {
@@ -6496,7 +6493,6 @@ bool reload_acl_and_cache(THD *thd, ulong options, TABLE_LIST *tables,
     if (reset_master(thd))
     {
       result=1;
-      thd->fatal_error();                       // Ensure client get error
     }
   }
 #endif

sql/sql_partition.cc

@@ -2068,6 +2068,7 @@ char *generate_partition_syntax(partition_info *part_info,
     default:
       DBUG_ASSERT(0);
       /* We really shouldn't get here, no use in continuing from here */
+      my_error(ER_OUT_OF_RESOURCES, MYF(0));
       current_thd->fatal_error();
       DBUG_RETURN(NULL);
   }

sql/sql_prepare.cc

@@ -230,6 +230,8 @@ static bool send_prep_stmt(Prepared_statement *stmt, uint columns)
   NET *net= &stmt->thd->net;
   uchar buff[12];
   uint tmp;
+  int error;
+  THD *thd= stmt->thd;
   DBUG_ENTER("send_prep_stmt");
 
   buff[0]= 0;                                   /* OK packet indicator */
@@ -244,11 +246,16 @@ static bool send_prep_stmt(Prepared_statement *stmt, uint columns)
     Send types and names of placeholders to the client
     XXX: fix this nasty upcast from List<Item_param> to List<Item>
   */
-  DBUG_RETURN(my_net_write(net, buff, sizeof(buff)) ||
+  error= my_net_write(net, buff, sizeof(buff));
-              (stmt->param_count &&
+  if (stmt->param_count && ! error)
-               stmt->thd->protocol_text.send_fields((List<Item> *)
+  {
+    error= thd->protocol_text.send_fields((List<Item> *)
                                           &stmt->lex->param_list,
-                                                    Protocol::SEND_EOF)));
+                                          Protocol::SEND_EOF);
+  }
+  /* Flag that a response has already been sent */
+  thd->main_da.disable_status();
+  DBUG_RETURN(error);
 }
 #else
 static bool send_prep_stmt(Prepared_statement *stmt,
@@ -259,6 +266,7 @@ static bool send_prep_stmt(Prepared_statement *stmt,
   thd->client_stmt_id= stmt->id;
   thd->client_param_count= stmt->param_count;
   thd->clear_error();
+  thd->main_da.disable_status();
 
   return 0;
 }
@@ -2526,6 +2534,8 @@ void mysql_stmt_close(THD *thd, char *packet)
   DBUG_ASSERT(! (stmt->flags & (uint) Prepared_statement::IS_IN_USE));
   (void) stmt->deallocate();
 
+  thd->main_da.disable_status();
+
   DBUG_VOID_RETURN;
 }
 
@@ -2590,6 +2600,8 @@ void mysql_stmt_get_longdata(THD *thd, char *packet, ulong packet_length)
   DBUG_ENTER("mysql_stmt_get_longdata");
 
   status_var_increment(thd->status_var.com_stmt_send_long_data);
+
+  thd->main_da.disable_status();
 #ifndef EMBEDDED_LIBRARY
   /* Minimal size of long data packet is 6 bytes */
   if (packet_length < MYSQL_LONG_DATA_HEADER)
@@ -2664,11 +2676,7 @@ bool Select_fetch_protocol_binary::send_fields(List<Item> &list, uint flags)
 
 bool Select_fetch_protocol_binary::send_eof()
 {
-  Protocol *save_protocol= thd->protocol;
-
-  thd->protocol= &protocol;
   ::send_eof(thd);
-  thd->protocol= save_protocol;
   return FALSE;
 }
 
@@ -3097,7 +3105,6 @@ bool Prepared_statement::execute(String *expanded_query, bool open_cursor)
                                           thd->query_length) <= 0)
     {
       error= mysql_execute_command(thd);
-      query_cache_end_of_result(thd);
     }
   }
 

sql/sql_select.cc

@@ -898,7 +898,6 @@ JOIN::optimize()
       }
       if (res > 1)
       {
-        thd->fatal_error();
         error= res;
         DBUG_PRINT("error",("Error from opt_sum_query"));
 	DBUG_RETURN(1);
@@ -14454,6 +14453,7 @@ calc_group_buffer(JOIN *join,ORDER *group)
       default:
         /* This case should never be choosen */
         DBUG_ASSERT(0);
+        my_error(ER_OUT_OF_RESOURCES, MYF(0));
         join->thd->fatal_error();
       }
     }

sql/sql_servers.cc

@@ -239,7 +239,7 @@ bool servers_reload(THD *thd)
   if (simple_open_n_lock_tables(thd, tables))
   {
     sql_print_error("Can't open and lock privilege tables: %s",
-		    thd->net.last_error);
+		    thd->main_da.message());
     goto end;
   }
 

sql/sql_show.cc

@@ -578,7 +578,8 @@ mysqld_show_create(THD *thd, TABLE_LIST *table_list)
   /* Only one table for now, but VIEW can involve several tables */
   if (open_normal_and_derived_tables(thd, table_list, 0))
   {
-    if (!table_list->view || thd->net.last_errno != ER_VIEW_INVALID)
+    if (!table_list->view ||
+        thd->is_error() && thd->main_da.sql_errno() != ER_VIEW_INVALID)
       DBUG_RETURN(TRUE);
 
     /*
@@ -786,10 +787,9 @@ mysqld_list_fields(THD *thd, TABLE_LIST *table_list, const char *wild)
   }
   restore_record(table, s->default_values);              // Get empty record
   table->use_all_columns();
-  if (thd->protocol->send_fields(&field_list, Protocol::SEND_DEFAULTS |
+  if (thd->protocol->send_fields(&field_list, Protocol::SEND_DEFAULTS))
-                                              Protocol::SEND_EOF))
     DBUG_VOID_RETURN;
-  thd->protocol->flush();
+  send_eof(thd);
   DBUG_VOID_RETURN;
 }
 
@@ -2919,7 +2919,7 @@ static int fill_schema_table_names(THD *thd, TABLE *table,
     default:
       DBUG_ASSERT(0);
     }
-    if (thd->net.last_errno == ER_NO_SUCH_TABLE)
+    if (thd->is_error() && thd->main_da.sql_errno() == ER_NO_SUCH_TABLE)
     {
       thd->clear_error();
       return 0;
@@ -3267,8 +3267,16 @@ int get_all_tables(THD *thd, TABLE_LIST *tables, COND *cond)
             res= open_normal_and_derived_tables(thd, show_table_list,
                                                 MYSQL_LOCK_IGNORE_FLUSH);
             lex->sql_command= save_sql_command;
-            
+            /*
-            if (thd->net.last_errno == ER_NO_SUCH_TABLE)
+              XXX:  show_table_list has a flag i_is_requested,
+              and when it's set, open_normal_and_derived_tables()
+              can return an error without setting an error message
+              in THD, which is a hack. This is why we have to
+              check for res, then for thd->is_error() only then
+              for thd->main_da.sql_errno().
+            */
+            if (res && thd->is_error() &&
+                thd->main_da.sql_errno() == ER_NO_SUCH_TABLE)
             {
               /*
                 Hide error for not existing table.
@@ -3422,7 +3430,7 @@ static int get_schema_tables_record(THD *thd, TABLE_LIST *tables,
     /*
       there was errors during opening tables
     */
-    const char *error= thd->net.last_error;
+    const char *error= thd->main_da.message();
     if (tables->view)
       table->field[3]->store(STRING_WITH_LEN("VIEW"), cs);
     else if (tables->schema_table)
@@ -3624,7 +3632,7 @@ static int get_schema_column_record(THD *thd, TABLE_LIST *tables,
         rather than in SHOW COLUMNS
       */ 
       push_warning(thd, MYSQL_ERROR::WARN_LEVEL_WARN,
-                   thd->net.last_errno, thd->net.last_error);
+                   thd->main_da.sql_errno(), thd->main_da.message());
       thd->clear_error();
       res= 0;
     }
@@ -4098,9 +4106,9 @@ static int get_schema_stat_record(THD *thd, TABLE_LIST *tables,
         I.e. we are in SELECT FROM INFORMATION_SCHEMA.STATISTICS
         rather than in SHOW KEYS
       */
-      if (thd->net.last_errno)
+      if (thd->is_error())
         push_warning(thd, MYSQL_ERROR::WARN_LEVEL_WARN,
-                     thd->net.last_errno, thd->net.last_error);
+                     thd->main_da.sql_errno(), thd->main_da.message());
       thd->clear_error();
       res= 0;
     }
@@ -4290,9 +4298,9 @@ static int get_schema_views_record(THD *thd, TABLE_LIST *tables,
 
     if (schema_table_store_record(thd, table))
       DBUG_RETURN(1);
-    if (res && thd->net.last_errno)
+    if (res && thd->is_error())
       push_warning(thd, MYSQL_ERROR::WARN_LEVEL_WARN, 
-                   thd->net.last_errno, thd->net.last_error);
+                   thd->main_da.sql_errno(), thd->main_da.message());
   }
   if (res) 
     thd->clear_error();
@@ -4323,9 +4331,9 @@ static int get_schema_constraints_record(THD *thd, TABLE_LIST *tables,
   DBUG_ENTER("get_schema_constraints_record");
   if (res)
   {
-    if (thd->net.last_errno)
+    if (thd->is_error())
       push_warning(thd, MYSQL_ERROR::WARN_LEVEL_WARN,
-                   thd->net.last_errno, thd->net.last_error);
+                   thd->main_da.sql_errno(), thd->main_da.message());
     thd->clear_error();
     DBUG_RETURN(0);
   }
@@ -4428,9 +4436,9 @@ static int get_schema_triggers_record(THD *thd, TABLE_LIST *tables,
   */
   if (res)
   {
-    if (thd->net.last_errno)
+    if (thd->is_error())
       push_warning(thd, MYSQL_ERROR::WARN_LEVEL_WARN,
-                   thd->net.last_errno, thd->net.last_error);
+                   thd->main_da.sql_errno(), thd->main_da.message());
     thd->clear_error();
     DBUG_RETURN(0);
   }
@@ -4511,9 +4519,9 @@ static int get_schema_key_column_usage_record(THD *thd,
   DBUG_ENTER("get_schema_key_column_usage_record");
   if (res)
   {
-    if (thd->net.last_errno)
+    if (thd->is_error())
       push_warning(thd, MYSQL_ERROR::WARN_LEVEL_WARN,
-                   thd->net.last_errno, thd->net.last_error);
+                   thd->main_da.sql_errno(), thd->main_da.message());
     thd->clear_error();
     DBUG_RETURN(0);
   }
@@ -4706,9 +4714,9 @@ static int get_schema_partitions_record(THD *thd, TABLE_LIST *tables,
 
   if (res)
   {
-    if (thd->net.last_errno)
+    if (thd->is_error())
       push_warning(thd, MYSQL_ERROR::WARN_LEVEL_WARN,
-                   thd->net.last_errno, thd->net.last_error);
+                   thd->main_da.sql_errno(), thd->main_da.message());
     thd->clear_error();
     DBUG_RETURN(0);
   }
@@ -4751,6 +4759,7 @@ static int get_schema_partitions_record(THD *thd, TABLE_LIST *tables,
       break;
     default:
       DBUG_ASSERT(0);
+      my_error(ER_OUT_OF_RESOURCES, MYF(0));
       current_thd->fatal_error();
       DBUG_RETURN(1);
     }
@@ -5243,9 +5252,9 @@ get_referential_constraints_record(THD *thd, TABLE_LIST *tables,
 
   if (res)
   {
-    if (thd->net.last_errno)
+    if (thd->is_error())
       push_warning(thd, MYSQL_ERROR::WARN_LEVEL_WARN,
-                   thd->net.last_errno, thd->net.last_error);
+                   thd->main_da.sql_errno(), thd->main_da.message());
     thd->clear_error();
     DBUG_RETURN(0);
   }

sql/sql_table.cc

@@ -1662,7 +1662,10 @@ int mysql_rm_table_part2(THD *thd, TABLE_LIST *tables, bool if_exists,
                              !dont_log_query);
       if ((error == ENOENT || error == HA_ERR_NO_SUCH_TABLE) && 
 	  (if_exists || table_type == NULL))
+      {
 	error= 0;
+        thd->clear_error();
+      }
       if (error == HA_ERR_ROW_IS_REFERENCED)
       {
 	/* the table is referenced by a foreign key constraint */
@@ -4191,18 +4194,22 @@ static bool mysql_admin_table(THD* thd, TABLE_LIST* tables,
           (table->table->file->ha_check_for_upgrade(check_opt) ==
            HA_ADMIN_NEEDS_ALTER))
       {
-        my_bool save_no_send_ok= thd->net.no_send_ok;
         DBUG_PRINT("admin", ("recreating table"));
         ha_autocommit_or_rollback(thd, 1);
         close_thread_tables(thd);
         tmp_disable_binlog(thd); // binlogging is done by caller if wanted
-        thd->net.no_send_ok= TRUE;
         result_code= mysql_recreate_table(thd, table);
-        thd->net.no_send_ok= save_no_send_ok;
         reenable_binlog(thd);
+        /*
+          mysql_recreate_table() can push OK or ERROR.
+          Clear 'OK' status. If there is an error, keep it:
+          we will store the error message in a result set row 
+          and then clear.
+        */
+        if (thd->main_da.is_ok())
+          thd->main_da.reset_diagnostics_area();
         goto send_result;
       }
-
     }
 
     DBUG_PRINT("admin", ("calling operator_func '%s'", operator_name));
@@ -4296,7 +4303,6 @@ send_result_message:
 
     case HA_ADMIN_TRY_ALTER:
     {
-      my_bool save_no_send_ok= thd->net.no_send_ok;
       /*
         This is currently used only by InnoDB. ha_innobase::optimize() answers
         "try with alter", so here we close the table, do an ALTER TABLE,
@@ -4308,10 +4314,16 @@ send_result_message:
                  *save_next_global= table->next_global;
       table->next_local= table->next_global= 0;
       tmp_disable_binlog(thd); // binlogging is done by caller if wanted
-      thd->net.no_send_ok= TRUE;
       result_code= mysql_recreate_table(thd, table);
-      thd->net.no_send_ok= save_no_send_ok;
       reenable_binlog(thd);
+      /*
+        mysql_recreate_table() can push OK or ERROR.
+        Clear 'OK' status. If there is an error, keep it:
+        we will store the error message in a result set row 
+        and then clear.
+      */
+      if (thd->main_da.is_ok())
+        thd->main_da.reset_diagnostics_area();
       ha_autocommit_or_rollback(thd, 0);
       close_thread_tables(thd);
       if (!result_code) // recreation went ok
@@ -4322,9 +4334,10 @@ send_result_message:
       }
       if (result_code) // either mysql_recreate_table or analyze failed
       {
-        const char *err_msg;
+        DBUG_ASSERT(thd->is_error());
-        if ((err_msg= thd->net.last_error))
+        if (thd->is_error())
         {
+          const char *err_msg= thd->main_da.message();
           if (!thd->vio_ok())
           {
             sql_print_error(err_msg);
@@ -4340,6 +4353,7 @@ send_result_message:
             protocol->store(table_name, system_charset_info);
             protocol->store(operator_name, system_charset_info);
           }
+          thd->clear_error();
         }
       }
       result_code= result_code ? HA_ADMIN_FAILED : HA_ADMIN_OK;

sql/sql_update.cc

@@ -1696,7 +1696,11 @@ void multi_update::send_error(uint errcode,const char *err)
 {
   /* First send error what ever it is ... */
   my_error(errcode, MYF(0), err);
+}
 
+
+void multi_update::abort()
+{
   /* the error was handled or nothing deleted and no side effects return */
   if (error_handled ||
       !thd->transaction.stmt.modified_non_trans_table && !updated)

sql/table.cc

@@ -3275,31 +3275,32 @@ bool TABLE_LIST::prep_check_option(THD *thd, uint8 check_opt_type)
 }
 
 
-/*
+/**
   Hide errors which show view underlying table information
 
-  SYNOPSIS
+  @param[in,out]  thd     thread handler
-    TABLE_LIST::hide_view_error()
-    thd     thread handler
 
+  @pre This method can be called only if there is an error.
 */
 
 void TABLE_LIST::hide_view_error(THD *thd)
 {
   /* Hide "Unknown column" or "Unknown function" error */
-  if (thd->net.last_errno == ER_BAD_FIELD_ERROR ||
+  DBUG_ASSERT(thd->is_error());
-      thd->net.last_errno == ER_SP_DOES_NOT_EXIST ||
+
-      thd->net.last_errno == ER_PROCACCESS_DENIED_ERROR ||
+  if (thd->main_da.sql_errno() == ER_BAD_FIELD_ERROR ||
-      thd->net.last_errno == ER_COLUMNACCESS_DENIED_ERROR ||
+      thd->main_da.sql_errno() == ER_SP_DOES_NOT_EXIST ||
-      thd->net.last_errno == ER_TABLEACCESS_DENIED_ERROR ||
+      thd->main_da.sql_errno() == ER_PROCACCESS_DENIED_ERROR ||
-      thd->net.last_errno == ER_TABLE_NOT_LOCKED ||
+      thd->main_da.sql_errno() == ER_COLUMNACCESS_DENIED_ERROR ||
-      thd->net.last_errno == ER_NO_SUCH_TABLE)
+      thd->main_da.sql_errno() == ER_TABLEACCESS_DENIED_ERROR ||
+      thd->main_da.sql_errno() == ER_TABLE_NOT_LOCKED ||
+      thd->main_da.sql_errno() == ER_NO_SUCH_TABLE)
   {
     TABLE_LIST *top= top_table();
     thd->clear_error();
     my_error(ER_VIEW_INVALID, MYF(0), top->view_db.str, top->view_name.str);
   }
-  else if (thd->net.last_errno == ER_NO_DEFAULT_FOR_FIELD)
+  else if (thd->main_da.sql_errno() == ER_NO_DEFAULT_FOR_FIELD)
   {
     TABLE_LIST *top= top_table();
     thd->clear_error();

sql/tztime.cc

@@ -1642,7 +1642,7 @@ my_tz_init(THD *org_thd, const char *default_tzname, my_bool bootstrap)
   if (open_system_tables_for_read(thd, tz_tables, &open_tables_state_backup))
   {
     sql_print_warning("Can't open and lock time zone table: %s "
-                      "trying to live without them", thd->net.last_error);
+                      "trying to live without them", thd->main_da.message());
     /* We will try emulate that everything is ok */
     return_val= time_zone_tables_exist= 0;
     goto end_with_setting_default_tz;