mariadb/sql/procedure.h

#ifndef PROCEDURE_INCLUDED
#define PROCEDURE_INCLUDED

/* Copyright (c) 2000, 2010, Oracle and/or its affiliates. All rights reserved.
   Copyright (c) 2009, 2020, MariaDB Corporation.

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; version 2 of the License.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1335  USA */

/* When using sql procedures */

#ifdef USE_PRAGMA_INTERFACE
#pragma interface				/* gcc class implementation */
#endif

/*
  It is necessary to include set_var.h instead of item.h because there
  are dependencies on include order for set_var.h and item.h. This
  will be resolved later.
*/
#include "sql_class.h"                          /* select_result, set_var.h: THD */
#include "set_var.h"                            /* Item */

#define PROC_NO_SORT 1				/**< Bits in flags */
#define PROC_GROUP   2				/**< proc must have group */

/* Procedure items used by procedures to store values for send_result_set_metadata */

class Item_proc :public Item
{
public:
  Item_proc(THD *thd, const char *name_par): Item(thd)
  {
     this->name.str=    name_par;
     this->name.length= strlen(name_par);
  }
  enum Type type() const override { return Item::PROC_ITEM; }
  Field *create_tmp_field_ex(MEM_ROOT *root, TABLE *table, Tmp_field_src *src,
                             const Tmp_field_param *param) override
  {
    /*
      We can get to here when using a CURSOR for a query with PROCEDURE:
        DECLARE c CURSOR FOR SELECT * FROM t1 PROCEDURE analyse();
        OPEN c;
    */
    return create_tmp_field_ex_simple(root, table, src, param);
  }
  virtual void set(double nr)=0;
  virtual void set(const char *str,uint length,CHARSET_INFO *cs)=0;
  virtual void set(longlong nr)=0;
  const Type_handler *type_handler() const override=0;
  void set(const char *str) { set(str,(uint) strlen(str), default_charset()); }
  unsigned int size_of() { return sizeof(*this);}
  bool check_vcol_func_processor(void *arg) override
  {
    DBUG_ASSERT(0); // impossible
    return mark_unsupported_function("proc", arg, VCOL_IMPOSSIBLE);
  }
  bool get_date(THD *thd, MYSQL_TIME *ltime, date_mode_t fuzzydate) override
  {
    return type_handler()->Item_get_date_with_warn(thd, this, ltime, fuzzydate);
  }
  Item* do_get_copy(THD *thd) const override { return 0; }
};

class Item_proc_real :public Item_proc
{
  double value;
public:
  Item_proc_real(THD *thd, const char *name_par, uint dec):
    Item_proc(thd, name_par)
  {
     decimals=dec; max_length=float_length(dec);
  }
  const Type_handler *type_handler() const override
  { return &type_handler_double; }
  void set(double nr) override { value=nr; }
  void set(longlong nr) override { value=(double) nr; }
  void set(const char *str,uint length,CHARSET_INFO *cs) override
  {
    int err_not_used;
    char *end_not_used;
    value= cs->strntod((char*) str,length, &end_not_used, &err_not_used);
  }
  double val_real() override { return value; }
  longlong val_int() override { return (longlong) value; }
  String *val_str(String *s) override
  {
    s->set_real(value,decimals,default_charset());
    return s;
  }
  my_decimal *val_decimal(my_decimal *) override;
  unsigned int size_of() { return sizeof(*this);}
};

class Item_proc_int :public Item_proc
{
  longlong value;
public:
  Item_proc_int(THD *thd, const char *name_par): Item_proc(thd, name_par)
  { max_length=11; }
  const Type_handler *type_handler() const override
  {
    if (unsigned_flag)
      return &type_handler_ulonglong;
    return &type_handler_slonglong;
  }
  void set(double nr) override { value=(longlong) nr; }
  void set(longlong nr) override { value=nr; }
  void set(const char *str,uint length, CHARSET_INFO *cs) override
  { int err; value= cs->strntoll(str,length,10,NULL,&err); }
  double val_real() override { return (double) value; }
  longlong val_int() override { return value; }
  String *val_str(String *s) override
  { s->set(value, default_charset()); return s; }
  my_decimal *val_decimal(my_decimal *) override;
  unsigned int size_of() { return sizeof(*this);}
  Item *do_get_copy(THD *thd) const override { return nullptr; }
  Item *do_build_clone(THD *thd) const override { return nullptr; }
};


class Item_proc_string :public Item_proc
{
  String value;
public:
  Item_proc_string(THD *thd, const char *name_par, uint length):
    Item_proc(thd, name_par)
  {
    this->max_length=length;
    value.set_thread_specific();
  }
  const Type_handler *type_handler() const override
  { return &type_handler_varchar; }
  void set(double nr) override { value.set_real(nr, 2, default_charset()); }
  void set(longlong nr) override { value.set(nr, default_charset()); }
  void set(const char *str, uint length, CHARSET_INFO *cs) override
  { value.copy(str,length,cs); }
  double val_real() override
  {
    int err_not_used;
    char *end_not_used;
    CHARSET_INFO *cs= value.charset();
    return cs->strntod((char*) value.ptr(), value.length(),
		       &end_not_used, &err_not_used);
  }
  longlong val_int() override
  { 
    int err;
    CHARSET_INFO *cs=value.charset();
    return cs->strntoll(value.ptr(), value.length(), 10, NULL, &err);
  }
  String *val_str(String*) override
  {
    return null_value ? (String*) 0 : &value;
  }
  my_decimal *val_decimal(my_decimal *) override;
  void cleanup() override { value.free(); }
  unsigned int size_of() { return sizeof(*this);}  
  Item *do_get_copy(THD *thd) const override { return nullptr; }
  Item *do_build_clone(THD *thd) const override { return nullptr; }
};

/* The procedure class definitions */

class Procedure {
protected:
  List<Item> *fields;
  select_result *result;
public:
  const uint flags;
  ORDER *group,*param_fields;
  Procedure(select_result *res,uint flags_par) :result(res),flags(flags_par),
    group(0),param_fields(0) {}
  virtual ~Procedure() {group=param_fields=0; fields=0; }
  virtual void add(void)=0;
  virtual void end_group(void)=0;
  virtual int send_row(List<Item> &fields)=0;
  virtual bool change_columns(THD *thd, List<Item> &fields)= 0;
  virtual void update_refs(void) {}
  virtual int end_of_records() { return 0; }
};

Procedure *setup_procedure(THD *thd,ORDER *proc_param,select_result *result,
			   List<Item> &field_list,int *error);

#endif /* PROCEDURE_INCLUDED */