Merge sanja.is.com.ua:/home/bell/mysql/bk/work-bug7-5.0

into  sanja.is.com.ua:/home/bell/mysql/bk/work-merge-5.0


mysql-test/r/sp-error.result:
  Auto merged
mysql-test/r/trigger.result:
  Auto merged
mysql-test/t/sp-error.test:
  Auto merged
mysql-test/t/sp.test:
  Auto merged
mysql-test/t/trigger.test:
  Auto merged
sql/item_func.cc:
  Auto merged
sql/mysqld.cc:
  Auto merged
sql/set_var.cc:
  Auto merged
sql/sp_head.cc:
  Auto merged
sql/sp_head.h:
  Auto merged
sql/sql_base.cc:
  Auto merged
sql/sql_class.h:
  Auto merged
sql/sql_parse.cc:
  Auto merged
mysql-test/r/sp.result:
  merge
sql/share/errmsg.txt:
  merge

11 files changed, 309 insertions, 190 deletions

diff --git a/sql/item_func.cc b/sql/item_func.cc
index c20a774e57e..ef3ebde74e5 100644
--- a/sql/item_func.cc
+++ b/sql/item_func.cc
@@ -4690,10 +4690,16 @@ Item_func_sp::sp_result_field(void) const
 {
   Field *field;
   DBUG_ENTER("Item_func_sp::sp_result_field");
+  DBUG_PRINT("info", ("sp: %s, flags: %x, level: %lu",
+                      (m_sp ? "YES" : "NO"),
+                      (m_sp ? m_sp->m_flags : (uint)0),
+                      (m_sp ? m_sp->m_recursion_level : (ulong)0)));
 
   if (!m_sp)
   {
-    if (!(m_sp= sp_find_function(current_thd, m_name, TRUE)))
+    THD *thd= current_thd;
+    if (!(m_sp= sp_find_routine(thd, TYPE_ENUM_FUNCTION, m_name,
+                                &thd->sp_func_cache, TRUE)))
     {
       my_error(ER_SP_DOES_NOT_EXIST, MYF(0), "FUNCTION", m_name->m_qname.str);
       DBUG_RETURN(0);
@@ -4919,7 +4925,8 @@ Item_func_sp::find_and_check_access(THD *thd, ulong want_access,
   bool res= TRUE;
 
   *save= 0;                                     // Safety if error
-  if (! m_sp && ! (m_sp= sp_find_function(thd, m_name, TRUE)))
+  if (! m_sp && ! (m_sp= sp_find_routine(thd, TYPE_ENUM_FUNCTION, m_name,
+                                         &thd->sp_func_cache, TRUE)))
   {
     my_error(ER_SP_DOES_NOT_EXIST, MYF(0), "FUNCTION", m_name->m_qname.str);
     goto error;
diff --git a/sql/mysqld.cc b/sql/mysqld.cc
index 35032d1ec41..b5b95e48889 100644
--- a/sql/mysqld.cc
+++ b/sql/mysqld.cc
@@ -4545,6 +4545,7 @@ enum options_mysqld
   OPT_OPTIMIZER_PRUNE_LEVEL,
   OPT_UPDATABLE_VIEWS_WITH_LIMIT,
   OPT_SP_AUTOMATIC_PRIVILEGES,
+  OPT_MAX_SP_RECURSION_DEPTH,
   OPT_AUTO_INCREMENT, OPT_AUTO_INCREMENT_OFFSET,
   OPT_ENABLE_LARGE_PAGES,
   OPT_TIMED_MUTEXES,
@@ -5760,6 +5761,11 @@ The minimum value for this variable is 4096.",
    (gptr*) &global_system_variables.read_buff_size,
    (gptr*) &max_system_variables.read_buff_size,0, GET_ULONG, REQUIRED_ARG,
    128*1024L, IO_SIZE*2+MALLOC_OVERHEAD, ~0L, MALLOC_OVERHEAD, IO_SIZE, 0},
+  {"max_sp_recursion_depth", OPT_MAX_SP_RECURSION_DEPTH,
+   "Maximum stored procedure recursion depth. (discussed with docs).",
+   (gptr*) &global_system_variables.max_sp_recursion_depth,
+   (gptr*) &max_system_variables.max_sp_recursion_depth, 0, GET_ULONG,
+   OPT_ARG, 0, 0, 255, 0, 1, 0 },
 #ifdef HAVE_REPLICATION
   {"relay_log_purge", OPT_RELAY_LOG_PURGE,
    "0 = do not purge relay logs. 1 = purge them as soon as they are no more needed.",
diff --git a/sql/set_var.cc b/sql/set_var.cc
index 89ad00d7839..632c37d2296 100644
--- a/sql/set_var.cc
+++ b/sql/set_var.cc
@@ -261,6 +261,8 @@ sys_var_long_ptr	sys_max_relay_log_size("max_relay_log_size",
                                                fix_max_relay_log_size);
 sys_var_thd_ulong	sys_max_sort_length("max_sort_length",
 					    &SV::max_sort_length);
+sys_var_thd_ulong	sys_max_sp_recursion_depth("max_sp_recursion_depth",
+                                                   &SV::max_sp_recursion_depth);
 sys_var_max_user_conn   sys_max_user_connections("max_user_connections");
 sys_var_thd_ulong	sys_max_tmp_tables("max_tmp_tables",
 					   &SV::max_tmp_tables);
@@ -631,6 +633,7 @@ sys_var *sys_variables[]=
   &sys_max_relay_log_size,
   &sys_max_seeks_for_key,
   &sys_max_sort_length,
+  &sys_max_sp_recursion_depth,
   &sys_max_tmp_tables,
   &sys_max_user_connections,
   &sys_max_write_lock_count,
@@ -896,6 +899,8 @@ struct show_var_st init_vars[]= {
   {sys_max_relay_log_size.name, (char*) &sys_max_relay_log_size,    SHOW_SYS},
   {sys_max_seeks_for_key.name,  (char*) &sys_max_seeks_for_key,	    SHOW_SYS},
   {sys_max_sort_length.name,	(char*) &sys_max_sort_length,	    SHOW_SYS},
+  {sys_max_sp_recursion_depth.name,
+    (char*) &sys_max_sp_recursion_depth, SHOW_SYS},
   {sys_max_tmp_tables.name,	(char*) &sys_max_tmp_tables,	    SHOW_SYS},
   {sys_max_user_connections.name,(char*) &sys_max_user_connections, SHOW_SYS},
   {sys_max_write_lock_count.name, (char*) &sys_max_write_lock_count,SHOW_SYS},
diff --git a/sql/share/errmsg.txt b/sql/share/errmsg.txt
index d2da1d0a7a8..d0773e8af3b 100644
--- a/sql/share/errmsg.txt
+++ b/sql/share/errmsg.txt
@@ -5361,7 +5361,7 @@ ER_COMMIT_NOT_ALLOWED_IN_SF_OR_TRG
 ER_NO_DEFAULT_FOR_VIEW_FIELD
         eng "Field of view '%-.64s.%-.64s' underlying table doesn't have a default value"
 ER_SP_NO_RECURSION
-        eng "Recursive stored routines are not allowed."
+        eng "Recursive stored functions and triggers are not allowed."
 ER_TOO_BIG_SCALE 42000 S1009
         eng "Too big scale %d specified for column '%-.64s'. Maximum is %d."
 ER_TOO_BIG_PRECISION 42000 S1009
@@ -5425,3 +5425,5 @@ ER_TRG_NO_DEFINER
   eng "No definer attribute for trigger '%-.64s'.'%-.64s'. The trigger will be activated under the authorization of the invoker, which may have insufficient privileges. Please recreate the trigger."
 ER_OLD_FILE_FORMAT
   eng "'%-.64s' has an old format, you should re-create the '%s' object(s)"
+ER_SP_RECURSION_LIMIT
+        eng "Recursive limit %d (as set by the max_sp_recursion_depth variable) was exceeded for routine %.64s"
diff --git a/sql/sp.cc b/sql/sp.cc
index 6939f87b31a..861a41d8501 100644
--- a/sql/sp.cc
+++ b/sql/sp.cc
@@ -29,6 +29,11 @@ create_string(THD *thd, String *buf,
 	      const char *returns, ulong returnslen,
 	      const char *body, ulong bodylen,
 	      st_sp_chistics *chistics);
+static int
+db_load_routine(THD *thd, int type, sp_name *name, sp_head **sphp,
+                ulong sql_mode, const char *params, const char *returns,
+                const char *body, st_sp_chistics &chistics,
+                const char *definer, longlong created, longlong modified);
 
 /*
  *
@@ -377,87 +382,77 @@ db_find_routine(THD *thd, int type, sp_name *name, sp_head **sphp)
   close_proc_table(thd, &open_tables_state_backup);
   table= 0;
 
-  {
-    String defstr;
-    LEX *oldlex= thd->lex;
-    sp_rcontext *save_spcont= thd->spcont;
-    char olddb[128];
-    bool dbchanged;
-    enum enum_sql_command oldcmd= thd->lex->sql_command;
-    ulong old_sql_mode= thd->variables.sql_mode;
-    ha_rows select_limit= thd->variables.select_limit;
-
-    thd->variables.sql_mode= sql_mode;
-    thd->variables.select_limit= HA_POS_ERROR;
-
-    defstr.set_charset(system_charset_info);
-    if (!create_string(thd, &defstr,
-		       type,
-		       name,
-		       params, strlen(params),
-		       returns, strlen(returns),
-		       body, strlen(body),
-		       &chistics))
-    {
-      ret= SP_INTERNAL_ERROR;
-      goto done;
-    }
+  ret= db_load_routine(thd, type, name, sphp,
+                       sql_mode, params, returns, body, chistics,
+                       definer, created, modified);
+                       
+ done:
+  if (table)
+    close_proc_table(thd, &open_tables_state_backup);
+  DBUG_RETURN(ret);
+}
 
-    dbchanged= FALSE;
-    if ((ret= sp_use_new_db(thd, name->m_db.str, olddb, sizeof(olddb),
-			    1, &dbchanged)))
-      goto done;
 
-    {
-      /* This is something of a kludge. We need to initialize some fields
-       * in thd->lex (the unit and master stuff), and the easiest way to
-       * do it is, is to call mysql_init_query(), but this unfortunately
-       * resets teh value_list where we keep the CALL parameters. So we
-       * copy the list and then restore it. (... and found_semicolon too).
-       */
-      List<Item> tmpvals= thd->lex->value_list;
-      char *tmpfsc= thd->lex->found_semicolon;
-
-      lex_start(thd, (uchar*)defstr.c_ptr(), defstr.length());
-      thd->lex->value_list= tmpvals;
-      thd->lex->found_semicolon= tmpfsc;
-    }
+static int
+db_load_routine(THD *thd, int type, sp_name *name, sp_head **sphp,
+                ulong sql_mode, const char *params, const char *returns,
+                const char *body, st_sp_chistics &chistics,
+                const char *definer, longlong created, longlong modified)
+{
+  LEX *oldlex= thd->lex, newlex;
+  String defstr;
+  char olddb[128];
+  bool dbchanged;
+  ulong old_sql_mode= thd->variables.sql_mode;
+  ha_rows select_limit= thd->variables.select_limit;
+  int ret= SP_INTERNAL_ERROR;
+
+  thd->variables.sql_mode= sql_mode;
+  thd->variables.select_limit= HA_POS_ERROR;
+
+  thd->lex= &newlex;
+  newlex.current_select= NULL;
+
+  defstr.set_charset(system_charset_info);
+  if (!create_string(thd, &defstr,
+		     type,
+		     name,
+		     params, strlen(params),
+		     returns, strlen(returns),
+		     body, strlen(body),
+		     &chistics))
+    goto end;
 
-    thd->spcont= 0;
-    if (yyparse(thd) || thd->is_fatal_error || thd->lex->sphead == NULL)
-    {
-      LEX *newlex= thd->lex;
-      sp_head *sp= newlex->sphead;
+  dbchanged= FALSE;
+  if ((ret= sp_use_new_db(thd, name->m_db.str, olddb, sizeof(olddb),
+			  1, &dbchanged)))
+    goto end;
 
-      if (dbchanged && (ret= mysql_change_db(thd, olddb, 1)))
-	goto done;
-      if (sp)
-      {
-	delete sp;
-	newlex->sphead= NULL;
-      }
-      ret= SP_PARSE_ERROR;
-    }
-    else
-    {
-      if (dbchanged && (ret= mysql_change_db(thd, olddb, 1)))
-	goto db_done;
-      *sphp= thd->lex->sphead;
-      (*sphp)->set_definer((char*) definer, (uint) strlen(definer));
-      (*sphp)->set_info(created, modified, &chistics, sql_mode);
-      (*sphp)->optimize();
-    }
-db_done:
-    thd->spcont= save_spcont;
-    thd->lex->sql_command= oldcmd;
-    thd->variables.sql_mode= old_sql_mode;
-    thd->variables.select_limit= select_limit;
-  }
+  lex_start(thd, (uchar*)defstr.c_ptr(), defstr.length());
 
- done:
-  if (table)
-    close_proc_table(thd, &open_tables_state_backup);
-  DBUG_RETURN(ret);
+  if (yyparse(thd) || thd->is_fatal_error || newlex.sphead == NULL)
+  {
+    sp_head *sp= newlex.sphead;
+
+    if (dbchanged && (ret= mysql_change_db(thd, olddb, 1)))
+      goto end;
+    delete sp;
+    ret= SP_PARSE_ERROR;
+  }
+  else
+  {
+    if (dbchanged && (ret= mysql_change_db(thd, olddb, 1)))
+      goto end;
+    *sphp= newlex.sphead;
+    (*sphp)->set_info((char *)definer, (uint)strlen(definer),
+		      created, modified, &chistics, sql_mode);
+    (*sphp)->optimize();
+  }
+  thd->variables.sql_mode= old_sql_mode;
+  thd->variables.select_limit= select_limit;
+end:  
+  thd->lex= oldlex;
+  return ret;
 }
 
 
@@ -555,13 +550,12 @@ db_create_routine(THD *thd, int type, sp_head *sp)
 	store(sp->m_chistics->comment.str, sp->m_chistics->comment.length,
 	      system_charset_info);
 
-    if ((sp->m_type == TYPE_ENUM_FUNCTION) &&
-        !trust_function_creators && mysql_bin_log.is_open())
+    if (!trust_routine_creators && mysql_bin_log.is_open())
     {
       if (!sp->m_chistics->detistic)
       {
 	/*
-	  Note that this test is not perfect; one could use
+	  Note that for a _function_ this test is not enough; one could use
 	  a non-deterministic read-only function in an update statement.
 	*/
 	enum enum_sp_data_access access=
@@ -903,45 +897,106 @@ err:
 ******************************************************************************/
 
 /*
-  Obtain object representing stored procedure by its name from
+  Obtain object representing stored procedure/function by its name from
   stored procedures cache and looking into mysql.proc if needed.
 
   SYNOPSIS
-    sp_find_procedure()
+    sp_find_routine()
       thd        - thread context
+      type       - type of object (TYPE_ENUM_FUNCTION or TYPE_ENUM_PROCEDURE)
       name       - name of procedure
+      cp         - hash to look routine in
       cache_only - if true perform cache-only lookup
                    (Don't look in mysql.proc).
 
-  TODO
-    We should consider merging of sp_find_procedure() and
-    sp_find_function() into one sp_find_routine() function
-    (the same applies to other similarly paired functions).
-
   RETURN VALUE
     Non-0 pointer to sp_head object for the procedure, or
     0 - in case of error.
 */
 
 sp_head *
-sp_find_procedure(THD *thd, sp_name *name, bool cache_only)
+sp_find_routine(THD *thd, int type, sp_name *name, sp_cache **cp,
+                bool cache_only)
 {
   sp_head *sp;
-  DBUG_ENTER("sp_find_procedure");
-  DBUG_PRINT("enter", ("name: %.*s.%.*s",
-		       name->m_db.length, name->m_db.str,
-		       name->m_name.length, name->m_name.str));
+  ulong depth= (type == TYPE_ENUM_PROCEDURE ?
+                thd->variables.max_sp_recursion_depth :
+                0);
+
+  DBUG_ENTER("sp_find_routine");
+  DBUG_PRINT("enter", ("name:  %.*s.%.*s, type: %d, cache only %d",
+                       name->m_db.length, name->m_db.str,
+                       name->m_name.length, name->m_name.str,
+                       type, cache_only));
 
-  if (!(sp= sp_cache_lookup(&thd->sp_proc_cache, name)) && !cache_only)
+  if ((sp= sp_cache_lookup(cp, name)))
   {
-    if (db_find_routine(thd, TYPE_ENUM_PROCEDURE, name, &sp) == SP_OK)
-      sp_cache_insert(&thd->sp_proc_cache, sp);
+    ulong level;
+    DBUG_PRINT("info", ("found: 0x%lx", (ulong)sp));
+    if (sp->m_first_free_instance)
+    {
+      DBUG_PRINT("info", ("first free: 0x%lx, level: %lu, flags %x",
+                          (ulong)sp->m_first_free_instance,
+                          sp->m_first_free_instance->m_recursion_level,
+                          sp->m_first_free_instance->m_flags));
+      DBUG_ASSERT(!(sp->m_first_free_instance->m_flags & sp_head::IS_INVOKED));
+      if (sp->m_first_free_instance->m_recursion_level > depth)
+      {
+        sp->recursion_level_error();
+        DBUG_RETURN(0);
+      }
+      DBUG_RETURN(sp->m_first_free_instance);
+    }
+    level= sp->m_last_cached_sp->m_recursion_level + 1;
+    if (level > depth)
+    {
+      sp->recursion_level_error();
+      DBUG_RETURN(0);
+    }
+    {
+      sp_head *new_sp;
+      const char *returns= "";
+      char definer[HOSTNAME_LENGTH+USERNAME_LENGTH+2];
+      String retstr(64);
+      strxmov(definer, sp->m_definer_user.str, "@",
+                       sp->m_definer_host.str, NullS);
+      if (type == TYPE_ENUM_FUNCTION)
+      {
+        sp_returns_type(thd, retstr, sp);
+        returns= retstr.ptr();
+      }
+      if (db_load_routine(thd, type, name, &new_sp,
+                          sp->m_sql_mode, sp->m_params.str, returns,
+                          sp->m_body.str, *sp->m_chistics, definer,
+                          sp->m_created, sp->m_modified) == SP_OK)
+      {
+        sp->m_last_cached_sp->m_next_cached_sp= new_sp;
+        new_sp->m_recursion_level= level;
+        new_sp->m_first_instance= sp;
+        sp->m_last_cached_sp= sp->m_first_free_instance= new_sp;
+        DBUG_PRINT("info", ("added level: 0x%lx, level: %lu, flags %x",
+                          (ulong)new_sp, new_sp->m_recursion_level,
+                          new_sp->m_flags));
+        DBUG_RETURN(new_sp);
+      }
+      DBUG_RETURN(0);
+    }
+  }
+  if (!cache_only)
+  {
+    if (db_find_routine(thd, type, name, &sp) == SP_OK)
+    {
+      sp_cache_insert(cp, sp);
+      DBUG_PRINT("info", ("added new: 0x%lx, level: %lu, flags %x",
+                          (ulong)sp, sp->m_recursion_level,
+                          sp->m_flags));
+    }
   }
-
   DBUG_RETURN(sp);
 }
 
 
+
 int
 sp_exists_routine(THD *thd, TABLE_LIST *tables, bool any, bool no_error)
 {
@@ -959,8 +1014,10 @@ sp_exists_routine(THD *thd, TABLE_LIST *tables, bool any, bool no_error)
     lex_name.str= thd->strmake(table->table_name, lex_name.length);
     name= new sp_name(lex_db, lex_name);
     name->init_qname(thd);
-    if (sp_find_procedure(thd, name) != NULL ||
-        sp_find_function(thd, name) != NULL)
+    if (sp_find_routine(thd, TYPE_ENUM_PROCEDURE, name,
+                        &thd->sp_proc_cache, FALSE) != NULL ||
+        sp_find_routine(thd, TYPE_ENUM_FUNCTION, name,
+                        &thd->sp_func_cache, FALSE) != NULL)
     {
       if (any)
         DBUG_RETURN(1);
@@ -1028,7 +1085,8 @@ sp_show_create_procedure(THD *thd, sp_name *name)
   DBUG_ENTER("sp_show_create_procedure");
   DBUG_PRINT("enter", ("name: %.*s", name->m_name.length, name->m_name.str));
 
-  if ((sp= sp_find_procedure(thd, name)))
+  if ((sp= sp_find_routine(thd, TYPE_ENUM_PROCEDURE, name,
+                           &thd->sp_proc_cache, FALSE)))
   {
     int ret= sp->show_create_procedure(thd);
 
@@ -1054,42 +1112,6 @@ sp_show_status_procedure(THD *thd, const char *wild)
   FUNCTION
 ******************************************************************************/
 
-/*
-  Obtain object representing stored function by its name from
-  stored functions cache and looking into mysql.proc if needed.
-
-  SYNOPSIS
-    sp_find_function()
-      thd        - thread context
-      name       - name of function
-      cache_only - if true perform cache-only lookup
-                   (Don't look in mysql.proc).
-
-  NOTE
-    See TODO section for sp_find_procedure().
-
-  RETURN VALUE
-    Non-0 pointer to sp_head object for the function, or
-    0 - in case of error.
-*/
-
-sp_head *
-sp_find_function(THD *thd, sp_name *name, bool cache_only)
-{
-  sp_head *sp;
-  DBUG_ENTER("sp_find_function");
-  DBUG_PRINT("enter", ("name: %.*s", name->m_name.length, name->m_name.str));
-
-  if (!(sp= sp_cache_lookup(&thd->sp_func_cache, name)) &&
-      !cache_only)
-  {
-    if (db_find_routine(thd, TYPE_ENUM_FUNCTION, name, &sp) == SP_OK)
-      sp_cache_insert(&thd->sp_func_cache, sp);
-  }
-  DBUG_RETURN(sp);
-}
-
-
 int
 sp_create_function(THD *thd, sp_head *sp)
 {
@@ -1137,7 +1159,8 @@ sp_show_create_function(THD *thd, sp_name *name)
   DBUG_ENTER("sp_show_create_function");
   DBUG_PRINT("enter", ("name: %.*s", name->m_name.length, name->m_name.str));
 
-  if ((sp= sp_find_function(thd, name)))
+  if ((sp= sp_find_routine(thd, TYPE_ENUM_FUNCTION, name,
+                           &thd->sp_func_cache, FALSE)))
   {
     int ret= sp->show_create_function(thd);
 
@@ -1447,10 +1470,6 @@ sp_cache_routines_and_add_tables_aux(THD *thd, LEX *lex,
                               &thd->sp_func_cache : &thd->sp_proc_cache),
                               &name)))
     {
-      LEX *oldlex= thd->lex;
-      LEX *newlex= new st_lex;
-      thd->lex= newlex;
-      newlex->current_select= NULL;
       name.m_name.str= strchr(name.m_qname.str, '.');
       name.m_db.length= name.m_name.str - name.m_qname.str;
       name.m_db.str= strmake_root(thd->mem_root, name.m_qname.str,
@@ -1465,8 +1484,6 @@ sp_cache_routines_and_add_tables_aux(THD *thd, LEX *lex,
         else
           sp_cache_insert(&thd->sp_proc_cache, sp);
       }
-      delete newlex;
-      thd->lex= oldlex;
     }
     if (sp)
     {
@@ -1589,30 +1606,30 @@ create_string(THD *thd, String *buf,
 		 chistics->comment.length))
     return FALSE;
 
-  buf->append(STRING_WITH_LEN("CREATE "));
+  buf->append("CREATE ", 7);
   if (type == TYPE_ENUM_FUNCTION)
-    buf->append(STRING_WITH_LEN("FUNCTION "));
+    buf->append("FUNCTION ", 9);
   else
-    buf->append(STRING_WITH_LEN("PROCEDURE "));
+    buf->append("PROCEDURE ", 10);
   append_identifier(thd, buf, name->m_name.str, name->m_name.length);
   buf->append('(');
   buf->append(params, paramslen);
   buf->append(')');
   if (type == TYPE_ENUM_FUNCTION)
   {
-    buf->append(STRING_WITH_LEN(" RETURNS "));
+    buf->append(" RETURNS ", 9);
     buf->append(returns, returnslen);
   }
   buf->append('\n');
   switch (chistics->daccess) {
   case SP_NO_SQL:
-    buf->append(STRING_WITH_LEN("    NO SQL\n"));
+    buf->append("    NO SQL\n");
     break;
   case SP_READS_SQL_DATA:
-    buf->append(STRING_WITH_LEN("    READS SQL DATA\n"));
+    buf->append("    READS SQL DATA\n");
     break;
   case SP_MODIFIES_SQL_DATA:
-    buf->append(STRING_WITH_LEN("    MODIFIES SQL DATA\n"));
+    buf->append("    MODIFIES SQL DATA\n");
     break;
   case SP_DEFAULT_ACCESS:
   case SP_CONTAINS_SQL:
@@ -1620,12 +1637,12 @@ create_string(THD *thd, String *buf,
     break;
   }
   if (chistics->detistic)
-    buf->append(STRING_WITH_LEN("    DETERMINISTIC\n"));
+    buf->append("    DETERMINISTIC\n", 18);
   if (chistics->suid == SP_IS_NOT_SUID)
-    buf->append(STRING_WITH_LEN("    SQL SECURITY INVOKER\n"));
+    buf->append("    SQL SECURITY INVOKER\n", 25);
   if (chistics->comment.length)
   {
-    buf->append(STRING_WITH_LEN("    COMMENT "));
+    buf->append("    COMMENT ");
     append_unescaped(buf, chistics->comment.str, chistics->comment.length);
     buf->append('\n');
   }
diff --git a/sql/sp.h b/sql/sp.h
index 933e5793e4c..7f314b8903e 100644
--- a/sql/sp.h
+++ b/sql/sp.h
@@ -36,7 +36,8 @@ int
 sp_drop_db_routines(THD *thd, char *db);
 
 sp_head *
-sp_find_procedure(THD *thd, sp_name *name, bool cache_only = 0);
+sp_find_routine(THD *thd, int type, sp_name *name,
+                sp_cache **cp, bool cache_only);
 
 int
 sp_exists_routine(THD *thd, TABLE_LIST *procs, bool any, bool no_error);
@@ -57,9 +58,6 @@ sp_show_create_procedure(THD *thd, sp_name *name);
 int
 sp_show_status_procedure(THD *thd, const char *wild);
 
-sp_head *
-sp_find_function(THD *thd, sp_name *name, bool cache_only = 0);
-
 int
 sp_create_function(THD *thd, sp_head *sp);
 
diff --git a/sql/sp_head.cc b/sql/sp_head.cc
index 601d41a0afe..a6e88c08789 100644
--- a/sql/sp_head.cc
+++ b/sql/sp_head.cc
@@ -478,7 +478,8 @@ sp_head::operator delete(void *ptr, size_t size)
 
 sp_head::sp_head()
   :Query_arena(&main_mem_root, INITIALIZED_FOR_SP),
-   m_flags(0), m_returns_cs(NULL)
+   m_flags(0), m_returns_cs(NULL), m_recursion_level(0), m_next_cached_sp(0),
+   m_first_instance(this), m_first_free_instance(this), m_last_cached_sp(this)
 {
   extern byte *
     sp_table_key(const byte *ptr, uint *plen, my_bool first);
@@ -659,6 +660,7 @@ sp_head::create(THD *thd)
 sp_head::~sp_head()
 {
   destroy();
+  delete m_next_cached_sp;
   if (m_thd)
     restore_thd_mem_root(m_thd);
 }
@@ -885,6 +887,31 @@ static bool subst_spvars(THD *thd, sp_instr *instr, LEX_STRING *query_str)
 
 
 /*
+  Return appropriate error about recursion limit reaching
+
+  SYNOPSIS
+    sp_head::recursion_level_error()
+
+  NOTE
+    For functions and triggers we return error about prohibited recursion.
+    For stored procedures we return about reaching recursion limit.
+*/
+
+void sp_head::recursion_level_error()
+{
+  if (m_type == TYPE_ENUM_PROCEDURE)
+  {
+    THD *thd= current_thd;
+    my_error(ER_SP_RECURSION_LIMIT, MYF(0),
+             thd->variables.max_sp_recursion_depth,
+             m_name);
+  }
+  else
+    my_error(ER_SP_NO_RECURSION, MYF(0));
+}
+
+
+/*
   Execute the routine. The main instruction jump loop is there 
   Assume the parameters already set.
   
@@ -913,37 +940,31 @@ int sp_head::execute(THD *thd)
   Item_change_list old_change_list;
   String old_packet;
 
-  /* init per-instruction memroot */
-  init_alloc_root(&execute_mem_root, MEM_ROOT_BLOCK_SIZE, 0);
-
-
   /* Use some extra margin for possible SP recursion and functions */
-  if (check_stack_overrun(thd, 4*STACK_MIN_SIZE, olddb))
+  if (check_stack_overrun(thd, 8 * STACK_MIN_SIZE, (char*)&old_packet))
   {
     DBUG_RETURN(-1);
   }
 
-  if (m_flags & IS_INVOKED)
-  {
-    /*
-      We have to disable recursion for stored routines since in
-      many cases LEX structure and many Item's can't be used in
-      reentrant way now.
-
-      TODO: We can circumvent this problem by using separate
-      sp_head instances for each recursive invocation.
-
-      NOTE: Theoretically arguments of procedure can be evaluated
-      before its invocation so there should be no problem with
-      recursion. But since we perform cleanup for CALL statement
-      as for any other statement only after its execution, its LEX
-      structure is not reusable for recursive calls. Thus we have
-      to prohibit recursion for stored procedures too.
-    */
-    my_error(ER_SP_NO_RECURSION, MYF(0));
-    DBUG_RETURN(-1);
-  }
+  /* init per-instruction memroot */
+  init_alloc_root(&execute_mem_root, MEM_ROOT_BLOCK_SIZE, 0);
+
+  DBUG_ASSERT(!(m_flags & IS_INVOKED));
   m_flags|= IS_INVOKED;
+  m_first_instance->m_first_free_instance= m_next_cached_sp;
+  DBUG_PRINT("info", ("first free for 0x%lx ++: 0x%lx->0x%lx, level: %lu, flags %x",
+                      (ulong)m_first_instance, this, m_next_cached_sp,
+                      m_next_cached_sp->m_recursion_level,
+                      m_next_cached_sp->m_flags));
+  /*
+    Check that if there are not any instances after this one then
+    pointer to the last instance points on this instance or if there are
+    some instances after this one then recursion level of next instance
+    greater then recursion level of current instance on 1
+  */
+  DBUG_ASSERT((m_next_cached_sp == 0 &&
+               m_first_instance->m_last_cached_sp == this) ||
+              (m_recursion_level + 1 == m_next_cached_sp->m_recursion_level));
 
   dbchanged= FALSE;
   if (m_db.length &&
@@ -1118,6 +1139,29 @@ int sp_head::execute(THD *thd)
       ret= mysql_change_db(thd, olddb, 1);
   }
   m_flags&= ~IS_INVOKED;
+  DBUG_PRINT("info", ("first free for 0x%lx --: 0x%lx->0x%lx, level: %lu, flags %x",
+                      (ulong)m_first_instance,
+                      m_first_instance->m_first_free_instance, this,
+                      m_recursion_level, m_flags));
+  /*
+    Check that we have one of following:
+
+    1) there are not free instances which means that this instance is last
+    in the list of instances (pointer to the last instance point on it and
+    ther are not other instances after this one in the list)
+
+    2) There are some free instances which mean that first free instance
+    should go just after this one and recursion level of that free instance
+    should be on 1 more then recursion leven of this instance.
+  */
+  DBUG_ASSERT((m_first_instance->m_first_free_instance == 0 &&
+               this == m_first_instance->m_last_cached_sp &&
+               m_next_cached_sp == 0) ||
+              (m_first_instance->m_first_free_instance != 0 &&
+               m_first_instance->m_first_free_instance == m_next_cached_sp &&
+               m_first_instance->m_first_free_instance->m_recursion_level ==
+               m_recursion_level + 1));
+  m_first_instance->m_first_free_instance= this;
   DBUG_RETURN(ret);
 }
 
diff --git a/sql/sp_head.h b/sql/sp_head.h
index 9addec706e7..6334bca0fc6 100644
--- a/sql/sp_head.h
+++ b/sql/sp_head.h
@@ -143,6 +143,32 @@ public:
   LEX_STRING m_definer_host;
   longlong m_created;
   longlong m_modified;
+  /* Recursion level of the current SP instance. The levels are numbered from 0 */
+  ulong m_recursion_level;
+  /*
+    A list of diferent recursion level instances for the same procedure.
+    For every recursion level we have a sp_head instance. This instances
+    connected in the list. The list ordered by increasing recursion level
+    (m_recursion_level).
+  */
+  sp_head *m_next_cached_sp;
+  /*
+    Pointer to the first element of the above list
+  */
+  sp_head *m_first_instance;
+  /*
+    Pointer to the first free (non-INVOKED) routine in the list of
+    cached instances for this SP. This pointer is set only for the first
+    SP in the list of instences (see above m_first_cached_sp pointer).
+    The pointer equal to 0 if we have no free instances.
+    For non-first instance value of this pointer meanless (point to itself);
+  */
+  sp_head *m_first_free_instance;
+  /*
+    Pointer to the last element in the list of instances of the SP.
+    For non-first instance value of this pointer meanless (point to itself);
+  */
+  sp_head *m_last_cached_sp;
   /*
     Set containing names of stored routines used by this routine.
     Note that unlike elements of similar set for statement elements of this
@@ -266,6 +292,8 @@ public:
   void optimize();
   void opt_mark(uint ip);
 
+  void recursion_level_error();
+
   inline sp_instr *
   get_instr(uint i)
   {
diff --git a/sql/sql_base.cc b/sql/sql_base.cc
index cfd06008690..b765f2f53e2 100644
--- a/sql/sql_base.cc
+++ b/sql/sql_base.cc
@@ -1088,6 +1088,11 @@ TABLE *open_table(THD *thd, TABLE_LIST *table_list, MEM_ROOT *mem_root,
   /* find a unused table in the open table cache */
   if (refresh)
     *refresh=0;
+
+  /* an open table operation needs a lot of the stack space */
+  if (check_stack_overrun(thd, 8 * STACK_MIN_SIZE, (char *)&alias))
+    return 0;
+
   if (thd->killed)
     DBUG_RETURN(0);
   key_length= (uint) (strmov(strmov(key, table_list->db)+1,
diff --git a/sql/sql_class.h b/sql/sql_class.h
index e92bf3b2bec..ee24d9e904b 100644
--- a/sql/sql_class.h
+++ b/sql/sql_class.h
@@ -530,6 +530,7 @@ struct system_variables
   ulong completion_type;
   /* Determines which non-standard SQL behaviour should be enabled */
   ulong sql_mode;
+  ulong max_sp_recursion_depth;
   /* check of key presence in updatable view */
   ulong updatable_views_with_limit;
   ulong default_week_format;
diff --git a/sql/sql_parse.cc b/sql/sql_parse.cc
index 462d1d0fbcd..437e910d592 100644
--- a/sql/sql_parse.cc
+++ b/sql/sql_parse.cc
@@ -3682,7 +3682,8 @@ end_with_restore_list:
     if (check_access(thd,INSERT_ACL,"mysql",0,1,0,0))
       break;
 #ifdef HAVE_DLOPEN
-    if (sp_find_function(thd, lex->spname))
+    if (sp_find_routine(thd, TYPE_ENUM_FUNCTION, lex->spname,
+                        &thd->sp_func_cache, FALSE))
     {
       my_error(ER_UDF_EXISTS, MYF(0), lex->spname->m_name.str);
       goto error;
@@ -4216,7 +4217,8 @@ end_with_restore_list:
         By this moment all needed SPs should be in cache so no need to look 
         into DB. 
       */
-      if (!(sp= sp_find_procedure(thd, lex->spname, TRUE)))
+      if (!(sp= sp_find_routine(thd, TYPE_ENUM_PROCEDURE, lex->spname,
+                                &thd->sp_proc_cache, TRUE)))
       {
 	my_error(ER_SP_DOES_NOT_EXIST, MYF(0), "PROCEDURE",
                  lex->spname->m_qname.str);
@@ -4340,9 +4342,11 @@ end_with_restore_list:
 
       memcpy(&chistics, &lex->sp_chistics, sizeof(chistics));
       if (lex->sql_command == SQLCOM_ALTER_PROCEDURE)
-	sp= sp_find_procedure(thd, lex->spname);
+        sp= sp_find_routine(thd, TYPE_ENUM_PROCEDURE, lex->spname,
+                            &thd->sp_proc_cache, FALSE);
       else
-	sp= sp_find_function(thd, lex->spname);
+        sp= sp_find_routine(thd, TYPE_ENUM_FUNCTION, lex->spname,
+                            &thd->sp_func_cache, FALSE);
       mysql_reset_errors(thd, 0);
       if (! sp)
       {
@@ -4418,9 +4422,11 @@ end_with_restore_list:
       char *db, *name;
 
       if (lex->sql_command == SQLCOM_DROP_PROCEDURE)
-	sp= sp_find_procedure(thd, lex->spname);
+        sp= sp_find_routine(thd, TYPE_ENUM_PROCEDURE, lex->spname,
+                            &thd->sp_proc_cache, FALSE);
       else
-	sp= sp_find_function(thd, lex->spname);
+        sp= sp_find_routine(thd, TYPE_ENUM_FUNCTION, lex->spname,
+                            &thd->sp_func_cache, FALSE);
       mysql_reset_errors(thd, 0);
       if (sp)
       {