~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 DRIZZLED_FIELD_BLOB_H

#define DRIZZLED_FIELD_BLOB_H

#include <drizzled/field/str.h>

#include "drizzled/global_charset_info.h"

#include <string>

namespace drizzled

{

/**

 * Class representing a BLOB data type column

 */

class Field_blob :public Field_str {

protected:

  uint32_t packlength;

  String value;				// For temporaries

public:

  using Field::store;

  using Field::cmp;

  using Field::pack;

  using Field::unpack;

  using Field::val_int;

  using Field::val_str;

  Field_blob(unsigned char *ptr_arg,

             unsigned char *null_ptr_arg,

             unsigned char null_bit_arg,

             const char *field_name_arg,

             TableShare *share,

             uint32_t blob_pack_length,

             const CHARSET_INFO * const cs);

  Field_blob(uint32_t len_arg,

             bool maybe_null_arg,

             const char *field_name_arg,

             const CHARSET_INFO * const cs)

    :Field_str((unsigned char*) NULL,

               len_arg,

               maybe_null_arg ? (unsigned char *) "": 0,

               0,

               field_name_arg,

               cs),

    packlength(4)

  {

    flags|= BLOB_FLAG;

  }

  Field_blob(uint32_t len_arg,

             bool maybe_null_arg,

             const char *field_name_arg,

             const CHARSET_INFO * const cs,

             bool set_packlength)

    :Field_str((unsigned char*) NULL,

               len_arg,

               maybe_null_arg ? (unsigned char*) "": 0,

               0,

               field_name_arg,

               cs),

    packlength(4)

  {

    flags|= BLOB_FLAG;

    if (set_packlength)

    {

      uint32_t l_char_length= len_arg/cs->mbmaxlen;

      packlength= l_char_length <= 255 ? 1 :

                  l_char_length <= 65535 ? 2 :

                  l_char_length <= 16777215 ? 3 : 4;

    }

  }

  Field_blob(uint32_t packlength_arg)

    :Field_str((unsigned char*) 0,

               0,

               (unsigned char*) "",

               0,

               "temp",

               system_charset_info),

    packlength(packlength_arg) 

  {}

  enum_field_types type() const { return DRIZZLE_TYPE_BLOB;}

  enum ha_base_keytype key_type() const

    { return binary() ? HA_KEYTYPE_VARBINARY2 : HA_KEYTYPE_VARTEXT2; }

  int  store(const char *to,uint32_t length,

             const CHARSET_INFO * const charset);

  int  store(double nr);

  int  store(int64_t nr, bool unsigned_val);

  double val_real(void);

  int64_t val_int(void);

  String *val_str(String*,String *);

  my_decimal *val_decimal(my_decimal *);

  int cmp_max(const unsigned char *, const unsigned char *, uint32_t max_length);

  int cmp(const unsigned char *a,const unsigned char *b)

    { return cmp_max(a, b, UINT32_MAX); }

  int cmp(const unsigned char *a, uint32_t a_length, const unsigned char *b, uint32_t b_length);

  int cmp_binary(const unsigned char *a,const unsigned char *b, uint32_t max_length=UINT32_MAX);

  int key_cmp(const unsigned char *,const unsigned char*);

  int key_cmp(const unsigned char *str, uint32_t length);

  uint32_t key_length() const { return 0; }

  void sort_string(unsigned char *buff,uint32_t length);

  uint32_t pack_length() const;

  /**

     Return the packed length without the pointer size added.

     This is used to determine the size of the actual data in the row

     buffer.

     @returns The length of the raw data itself without the pointer.

  */

  uint32_t pack_length_no_ptr() const

  { return (uint32_t) (packlength); }

  uint32_t sort_length() const;

  virtual uint32_t max_data_length() const

  {

    return (uint32_t) (((uint64_t) 1 << (packlength*8)) -1);

  }

  int reset(void) { memset(ptr, 0, packlength+sizeof(unsigned char*)); return 0; }

  void reset_fields() { memset(&value, 0, sizeof(value)); }

#ifndef WORDS_BIGENDIAN

  static

#endif

  void store_length(unsigned char *i_ptr, uint32_t i_packlength,

                    uint32_t i_number, bool low_byte_first);

  void store_length(unsigned char *i_ptr, uint32_t i_packlength,

                    uint32_t i_number);

  inline void store_length(uint32_t number)

  {

    store_length(ptr, packlength, number);

  }

  /**

     Return the packed length plus the length of the data.

     This is used to determine the size of the data plus the

     packed length portion in the row data.

     @returns The length in the row plus the size of the data.

  */

  uint32_t get_packed_size(const unsigned char *ptr_arg, bool low_byte_first);

  uint32_t get_length(uint32_t row_offset= 0);

  uint32_t get_length(const unsigned char *ptr, uint32_t packlength,

                      bool low_byte_first);

  uint32_t get_length(const unsigned char *ptr_arg);

  void put_length(unsigned char *pos, uint32_t length);

  inline void get_ptr(unsigned char **str)

    {

      memcpy(str,ptr+packlength,sizeof(unsigned char*));

    }

  inline void get_ptr(unsigned char **str, uint32_t row_offset)

    {

      memcpy(str,ptr+packlength+row_offset,sizeof(char*));

    }

  inline void set_ptr(unsigned char *length, unsigned char *data)

    {

      memcpy(ptr,length,packlength);

      memcpy(ptr+packlength,&data,sizeof(char*));

    }

  void set_ptr_offset(ptrdiff_t ptr_diff, uint32_t length, unsigned char *data)

    {

      unsigned char *ptr_ofs= ADD_TO_PTR(ptr,ptr_diff,unsigned char*);

      store_length(ptr_ofs, packlength, length);

      memcpy(ptr_ofs+packlength,&data,sizeof(char*));

    }

  inline void set_ptr(uint32_t length, unsigned char *data)

    {

      set_ptr_offset(0, length, data);

    }

  uint32_t get_key_image(unsigned char *buff,uint32_t length);

  uint32_t get_key_image(std::basic_string<unsigned char> &buff, uint32_t length);

  void set_key_image(const unsigned char *buff,uint32_t length);

  void sql_type(String &str) const;

  inline bool copy()

  {

    unsigned char *tmp;

    get_ptr(&tmp);

    if (value.copy((char*) tmp, get_length(), charset()))

    {

      Field_blob::reset();

      return 1;

    }

    tmp=(unsigned char*) value.ptr();

    memcpy(ptr+packlength,&tmp,sizeof(char*));

    return 0;

  }

  virtual unsigned char *pack(unsigned char *to, const unsigned char *from,

                      uint32_t max_length, bool low_byte_first);

  unsigned char *pack_key(unsigned char *to, const unsigned char *from,

                  uint32_t max_length, bool low_byte_first);

  virtual const unsigned char *unpack(unsigned char *to, const unsigned char *from,

                              uint32_t param_data, bool low_byte_first);

  void free() { value.free(); }

  inline void clear_temporary() { memset(&value, 0, sizeof(value)); }

  friend int field_conv(Field *to,Field *from);

  uint32_t size_of() const { return sizeof(*this); }

  bool has_charset(void) const

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

  uint32_t max_display_length();

};

} /* namespace drizzled */

#endif /* DRIZZLED_FIELD_BLOB_H */