~drizzle-trunk/drizzle/development

/* - mode: c; c-basic-offset: 2; indent-tabs-mode: nil; -*-

 *  vim:expandtab:shiftwidth=2:tabstop=2:smarttab:

 *

 *  Copyright (C) 2008 MySQL

 *

 *  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; either version 2 of the License, or

 *  (at your option) any later version.

 *

 *  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  02110-1301  USA

 */

#ifndef DRIZZLE_SERVER_FIELD_VARSTRING

#define DRIZZLE_SERVER_FIELD_VARSTRING

class Field_varstring :public Field_longstr {

public:

  /*

    The maximum space available in a Field_varstring, in bytes. See

    length_bytes.

  */

  static const uint MAX_SIZE;

  /* Store number of bytes used to store length (1 or 2) */

  uint32_t length_bytes;

  Field_varstring(uchar *ptr_arg,

                  uint32_t len_arg, uint length_bytes_arg,

                  uchar *null_ptr_arg, uchar null_bit_arg,

		  enum utype unireg_check_arg, const char *field_name_arg,

		  TABLE_SHARE *share, const CHARSET_INFO * const cs)

    :Field_longstr(ptr_arg, len_arg, null_ptr_arg, null_bit_arg,

                   unireg_check_arg, field_name_arg, cs),

     length_bytes(length_bytes_arg)

  {

    share->varchar_fields++;

  }

  Field_varstring(uint32_t len_arg,bool maybe_null_arg,

                  const char *field_name_arg,

                  TABLE_SHARE *share, const CHARSET_INFO * const cs)

    :Field_longstr((uchar*) 0,len_arg, maybe_null_arg ? (uchar*) "": 0, 0,

                   NONE, field_name_arg, cs),

     length_bytes(len_arg < 256 ? 1 :2)

  {

    share->varchar_fields++;

  }

  enum_field_types type() const { return DRIZZLE_TYPE_VARCHAR; }

  enum ha_base_keytype key_type() const;

  uint row_pack_length() { return field_length; }

  bool zero_pack() const { return 0; }

  int  reset(void) { memset(ptr, 0, field_length+length_bytes); return 0; }

  uint32_t pack_length() const { return (uint32_t) field_length+length_bytes; }

  uint32_t key_length() const { return (uint32_t) field_length; }

  uint32_t sort_length() const

  {

    return (uint32_t) field_length + (field_charset == &my_charset_bin ?

                                    length_bytes : 0);

  }

  int  store(const char *to,uint length, const CHARSET_INFO * const charset);

  int  store(int64_t nr, bool unsigned_val);

  int  store(double nr) { return Field_str::store(nr); } /* QQ: To be deleted */

  double val_real(void);

  int64_t val_int(void);

  String *val_str(String*,String *);

  my_decimal *val_decimal(my_decimal *);

  int cmp_max(const uchar *, const uchar *, uint32_t max_length);

  int cmp(const uchar *a,const uchar *b)

  {

    return cmp_max(a, b, UINT32_MAX);

  }

  void sort_string(uchar *buff,uint length);

  uint get_key_image(uchar *buff,uint length, imagetype type);

  void set_key_image(const uchar *buff,uint length);

  void sql_type(String &str) const;

  virtual uchar *pack(uchar *to, const uchar *from,

                      uint max_length, bool low_byte_first);

  uchar *pack_key(uchar *to, const uchar *from, uint max_length, bool low_byte_first);

  uchar *pack_key_from_key_image(uchar* to, const uchar *from,

                                 uint max_length, bool low_byte_first);

  virtual const uchar *unpack(uchar* to, const uchar *from,

                              uint param_data, bool low_byte_first);

  const uchar *unpack_key(uchar* to, const uchar *from,

                          uint max_length, bool low_byte_first);

  int pack_cmp(const uchar *a, const uchar *b, uint key_length,

               bool insert_or_update);

  int pack_cmp(const uchar *b, uint key_length,bool insert_or_update);

  int cmp_binary(const uchar *a,const uchar *b, uint32_t max_length=~0L);

  int key_cmp(const uchar *,const uchar*);

  int key_cmp(const uchar *str, uint length);

  uint packed_col_length(const uchar *to, uint length);

  uint max_packed_col_length(uint max_length);

  uint32_t data_length();

  uint32_t used_length();

  uint size_of() const { return sizeof(*this); }

  enum_field_types real_type() const { return DRIZZLE_TYPE_VARCHAR; }

  bool has_charset(void) const

  { return charset() == &my_charset_bin ? false : true; }

  Field *new_field(MEM_ROOT *root, Table *new_table, bool keep_type);

  Field *new_key_field(MEM_ROOT *root, Table *new_table,

                       uchar *new_ptr, uchar *new_null_ptr,

                       uint new_null_bit);

  uint is_equal(Create_field *new_field);

  void hash(uint32_t *nr, uint32_t *nr2);

private:

  int do_save_field_metadata(uchar *first_byte);

};

#endif