Recursion support made for SP (BUG#10100).

client/mysqltest.c:
  An expected error messages hiding from the log if disable_result_log is in force.
mysql-test/r/sp-dynamic.result:
  The test expanded for case of allowed/disalowed recursion.
mysql-test/r/sp-error.result:
  Error messages changed.
  Test of bug11394() made with allowed recursion.
mysql-test/r/sp.result:
  Tests for recursion.
mysql-test/r/trigger.result:
  Check that triggers are not affected by this patch.
mysql-test/r/variables.result:
  Test of max_sp_recursion_depth variable.
mysql-test/t/sp-dynamic.test:
  The test expanded for case of allowed/disalowed recursion.
mysql-test/t/sp-error.test:
  Error messages changed.
  Test of bug11394() made with allowed recursion.
mysql-test/t/sp.test:
  Tests for recursion.
mysql-test/t/trigger.test:
  Check that triggers are not affected by this patch.
mysql-test/t/variables.test:
  Test of max_sp_recursion_depth variable.
sql/item_func.cc:
  sp_find_function() and sp_find_procedure() joined to sp_find_routine()
    function as it was mentioned in TODO.
sql/mysqld.cc:
  max_sp_recursion_depth variable added.
sql/set_var.cc:
  max_sp_recursion_depth variable added.
sql/share/errmsg.txt:
  An error message changed.
  An error message added.
sql/sp.cc:
  sp_find_function() and sp_find_procedure() joined to sp_find_routine()
    function as it was mentioned in TODO.
  Temory LEX is allocated on a stack, not on a heap.
  Recursion support added for stored procedures.
sql/sp.h:
  sp_find_function() and sp_find_procedure() joined to sp_find_routine()
    function as it was mentioned in TODO.
sql/sp_head.cc:
  Initialization of new sp_head fields to get correct list of instances
    contained one instance only.
  Stack requirement for SP instruction is increased.
  Stack free space is checked before mem root initialisation to avoid
    memory leak.
  Pointer to the free instance management added before and after
    SP execution.
sql/sp_head.h:
  New sp_head variables added to support inst of instances of SP
    for recursion and pointer on ths first free to use instance.
sql/sql_base.cc:
  open_table() consume a lot of stack space so we check free stack space before it.
sql/sql_class.h:
  max_sp_recursion_depth variable added.
sql/sql_parse.cc:
  sp_find_function() and sp_find_procedure() joined to sp_find_routine()
    function as it was mentioned in TODO.

1 files changed, 156 insertions, 134 deletions

diff --git a/sql/sp.cc b/sql/sp.cc
index 8386c5d58a2..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);
 
 /*
  *
@@ -377,83 +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;
-    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;
 
-    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 done;
-      *sphp= thd->lex->sphead;
-      (*sphp)->set_info((char *)definer, (uint)strlen(definer),
-			created, modified, &chistics, sql_mode);
-      (*sphp)->optimize();
-    }
-    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;
 }
 
 
@@ -898,45 +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)))
+  {
+    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_ENUM_PROCEDURE, name, &sp) == SP_OK)
-      sp_cache_insert(&thd->sp_proc_cache, sp);
+    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)
 {
@@ -954,8 +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);
@@ -1023,7 +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);
 
@@ -1049,42 +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)
 {
@@ -1132,7 +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);
 
@@ -1442,10 +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,
@@ -1460,8 +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)
     {