Commit 9b16a7b9 authored by aelkin@mysql.com's avatar aelkin@mysql.com
Browse files

BUG#19188: incorrect temporary table name of DROP query in replication 

  A pattern to generate binlog for DROPped temp table in close_temporary_tables
  was buggy: could not deal with a grave-accent-in-name table.

  The fix exploits `append_identifier()' for quoting and duplicating accents.
parent 0928ae9b

mysql-test/r/rpl_temporary.result

+8 −5
Original line number Diff line number Diff line
@@ -89,14 +89,17 @@ f 
7

drop table t1,t2;

create temporary table t3 (f int);

set @session.pseudo_thread_id=100;

set @@session.pseudo_thread_id=100;

create temporary table t101 (id int);

create temporary table t102 (id int);

set @session.pseudo_thread_id=200;

set @@session.pseudo_thread_id=200;

create temporary table t201 (id int);

create temporary table `#not_user_table_prefixed_with_hash_sign_no_harm` (id int);

set @con1_id=connection_id();

kill @con1_id;

create temporary table `t``201` (id int);

create temporary table `#sql_not_user_table202` (id int);

set @@session.pseudo_thread_id=300;

create temporary table t301 (id int);

create temporary table t302 (id int);

create temporary table `#sql_not_user_table303` (id int);

create table t1(f int);

insert into t1 values (1);

select * from t1 /* must be 1 */;

mysql-test/t/rpl_temporary.test

+10 −5
Original line number Diff line number Diff line
@@ -135,14 +135,19 @@ sync_with_master; 
# value was set up at the moment of temp table creation

#

connection con1;

set @session.pseudo_thread_id=100;

set @@session.pseudo_thread_id=100;

create temporary table t101 (id int);

create temporary table t102 (id int);

set @session.pseudo_thread_id=200;

set @@session.pseudo_thread_id=200;

create temporary table t201 (id int);

create temporary table `#not_user_table_prefixed_with_hash_sign_no_harm` (id int);

set @con1_id=connection_id();

kill @con1_id;

create temporary table `t``201` (id int);

# emulate internal temp table not to come to binlog

create temporary table `#sql_not_user_table202` (id int);

set @@session.pseudo_thread_id=300;

create temporary table t301 (id int);

create temporary table t302 (id int);

create temporary table `#sql_not_user_table303` (id int);

disconnect con1;



#now do something to show that slave is ok after DROP temp tables

connection master;

sql/mysql_priv.h

+12 −0
Original line number Diff line number Diff line
@@ -1275,6 +1275,18 @@ inline int hexchar_to_int(char c) 
  return -1;

}



/*

  is_user_table()

  return true if the table was created explicitly

*/



inline bool is_user_table(TABLE * table)

{

  const char *name= table->real_name;

  return strncmp(name, tmp_file_prefix, tmp_file_prefix_length);

}







/*

  Some functions that are different in the embedded library and the normal

sql/sql_base.cc

+69 −78
Original line number Diff line number Diff line
@@ -493,46 +493,51 @@ static inline uint tmpkeyval(THD *thd, TABLE *table) 


void close_temporary_tables(THD *thd)

{

  TABLE *next,

    *prev_table /* prev link is not maintained in TABLE's double-linked list */,

    *table;

  char *query= (gptr) 0, *end;

  uint query_buf_size, max_names_len; 

  bool found_user_tables;



  TABLE *table;

  if (!thd->temporary_tables)

    return;

  

  LINT_INIT(end);

  query_buf_size= 50;   // Enough for DROP ... TABLE IF EXISTS

  if (!mysql_bin_log.is_open())

  {

    for (table= thd->temporary_tables; table; table= table->next)

    {

      close_temporary(table, 1);

    }

    thd->temporary_tables= 0;

    return;

  }



  TABLE *next,

    *prev_table /* prev link is not maintained in TABLE's double-linked list */;

  bool was_quote_show= true; /* to assume thd->options has OPTION_QUOTE_SHOW_CREATE */

  // Better add "if exists", in case a RESET MASTER has been done

  const char stub[]= "DROP /*!40005 TEMPORARY */ TABLE IF EXISTS ";

  uint stub_len= sizeof(stub) - 1;

  char buf[256];

  memcpy(buf, stub, stub_len);

  String s_query= String(buf, sizeof(buf), system_charset_info);

  bool found_user_tables= false;

  LINT_INIT(next);

  

  /* 

     insertion sort of temp tables by pseudo_thread_id to build ordered list 

     of sublists of equal pseudo_thread_id

  */

  for (prev_table= thd->temporary_tables, 

         table= prev_table->next,

         found_user_tables= (prev_table->real_name[0] != '#'); 

  

  for (prev_table= thd->temporary_tables, table= prev_table->next;

       table;

       prev_table= table, table= table->next)

  {

    TABLE *prev_sorted /* same as for prev_table */,

      *sorted;

    /*

      table not created directly by the user is moved to the tail. 

      Fixme/todo: nothing (I checked the manual) prevents user to create temp

      with `#' 

    */

    if (table->real_name[0] == '#')

      continue;

    else 

    TABLE *prev_sorted /* same as for prev_table */, *sorted;

    if (is_user_table(table))

    {

      found_user_tables = 1;

    }

      if (!found_user_tables)

        found_user_tables= true;

      for (prev_sorted= NULL, sorted= thd->temporary_tables; sorted != table; 

           prev_sorted= sorted, sorted= sorted->next)

      {

      if (sorted->real_name[0] == '#' || tmpkeyval(thd, sorted) > tmpkeyval(thd, table))

        if (!is_user_table(sorted) ||

            tmpkeyval(thd, sorted) > tmpkeyval(thd, table))

        {

          /* move into the sorted part of the list from the unsorted */

          prev_table->next= table->next;
@@ -550,61 +555,45 @@ void close_temporary_tables(THD *thd) 
        }

      }

    }

  /* 

     calc query_buf_size as max per sublists, one sublist per pseudo thread id.

     Also stop at first occurence of `#'-named table that starts 

     all implicitly created temp tables

  */

  for (max_names_len= 0, table=thd->temporary_tables; 

       table && table->real_name[0] != '#';

       table=table->next)

  {

    uint tmp_names_len;

    for (tmp_names_len= table->key_length + 1;

         table->next && table->real_name[0] != '#' &&

           tmpkeyval(thd, table) == tmpkeyval(thd, table->next);

         table=table->next)

    {

      /*

        We are going to add 4 ` around the db/table names, so 1 might not look

        enough; indeed it is enough, because table->key_length is greater (by 8,

        because of server_id and thread_id) than db||table.

      */

      tmp_names_len += table->next->key_length + 1;

    }

    if (tmp_names_len > max_names_len) max_names_len= tmp_names_len;

  }



  /* allocate */

  if (found_user_tables && mysql_bin_log.is_open() &&

      (query = alloc_root(thd->mem_root, query_buf_size+= max_names_len)))

    // Better add "if exists", in case a RESET MASTER has been done

    end= strmov(query, "DROP /*!40005 TEMPORARY */ TABLE IF EXISTS ");

  /* We always quote db,table names though it is slight overkill */

  if (found_user_tables &&

      !(was_quote_show= (thd->options & OPTION_QUOTE_SHOW_CREATE)))

  {

    thd->options |= OPTION_QUOTE_SHOW_CREATE;

  }

  

  /* scan sorted tmps to generate sequence of DROP */

  for (table= thd->temporary_tables; table; table= next)

  {

    if (query // we might be out of memory, but this is not fatal 

        && table->real_name[0] != '#') 

    if (is_user_table(table)) 

    {

      char *end_cur;

      /* Set pseudo_thread_id to be that of the processed table */

      thd->variables.pseudo_thread_id= tmpkeyval(thd, table);

      /* Loop forward through all tables within the sublist of

         common pseudo_thread_id to create single DROP query */

      for (end_cur= end;

           table && table->real_name[0] != '#' &&

      for (s_query.length(stub_len);

           table && is_user_table(table) &&

             tmpkeyval(thd, table) == thd->variables.pseudo_thread_id;

           table= next)

      {

        end_cur= strxmov(end_cur, "`", table->table_cache_key, "`.`",

                      table->real_name, "`,", NullS);

        /*

          We are going to add 4 ` around the db/table names and possible more

          due to special characters in the names

        */

        append_identifier(thd, &s_query, table->table_cache_key, strlen(table->table_cache_key));

        s_query.q_append('.');

        append_identifier(thd, &s_query, table->real_name,

                          strlen(table->real_name));

        s_query.q_append(',');

        next= table->next;

        close_temporary(table, 1);

      }

      thd->clear_error();

      /* The -1 is to remove last ',' */

      Query_log_event qinfo(thd, query, (ulong)(end_cur - query) - 1, 0, FALSE);

      Query_log_event qinfo(thd, s_query.ptr(),

                            s_query.length() - 1 /* to remove trailing ',' */,

                            0, FALSE);

      /*

        Imagine the thread had created a temp table, then was doing a SELECT, and

        the SELECT was killed. Then it's not clever to mark the statement above as
@@ -623,6 +612,8 @@ void close_temporary_tables(THD *thd) 
      close_temporary(table, 1);

    }

  }

  if (!was_quote_show)

    thd->options &= ~OPTION_QUOTE_SHOW_CREATE; /* restore option */

  thd->temporary_tables=0;

}