~drizzle-trunk/drizzle/development

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

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

 *

 *  Copyright (C) 2008 Sun Microsystems

 *

 *  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  02110-1301  USA

 */

#ifndef _SQL_BITMAP_H_

#define _SQL_BITMAP_H_

/*

  Implementation of a bitmap type.

  The idea with this is to be able to handle any constant number of bits but

  also be able to use 32 or 64 bits bitmaps very efficiently

*/

/// TODO: OMG FIX THIS

#include <mysys/my_bitmap.h>

#include <drizzled/util/test.h>

template <uint32_t default_width> class Bitmap

{

  MY_BITMAP map;

  uint32_t buffer[(default_width+31)/32];

public:

  Bitmap() : map() { init(); }

  Bitmap(const Bitmap& from) : map() { *this=from; }

  explicit Bitmap(uint32_t prefix_to_set) : map(0) { init(prefix_to_set); }

  void init() { bitmap_init(&map, buffer, default_width, 0); }

  void init(uint32_t prefix_to_set) { init(); set_prefix(prefix_to_set); }

  uint32_t length() const { return default_width; }

  Bitmap& operator=(const Bitmap& map2)

  {

    init();

    memcpy(buffer, map2.buffer, sizeof(buffer));

    return *this;

  }

  void set_bit(uint32_t n) { bitmap_set_bit(&map, n); }

  void clear_bit(uint32_t n) { bitmap_clear_bit(&map, n); }

  void set_prefix(uint32_t n) { bitmap_set_prefix(&map, n); }

  void set_all() { bitmap_set_all(&map); }

  void clear_all() { bitmap_clear_all(&map); }

  void intersect(Bitmap& map2) { bitmap_intersect(&map, &map2.map); }

  void intersect(uint64_t map2buff)

  {

    MY_BITMAP map2;

    bitmap_init(&map2, (uint32_t *)&map2buff, sizeof(uint64_t)*8, 0);

    bitmap_intersect(&map, &map2);

  }

  /* Use highest bit for all bits above sizeof(uint64_t)*8. */

  void intersect_extended(uint64_t map2buff)

  {

    intersect(map2buff);

    if (map.n_bits > sizeof(uint64_t) * 8)

      bitmap_set_above(&map, sizeof(uint64_t),

                       test(map2buff & (1 << (sizeof(uint64_t) * 8 - 1))));

  }

  void subtract(Bitmap& map2) { bitmap_subtract(&map, &map2.map); }

  void merge(Bitmap& map2) { bitmap_union(&map, &map2.map); }

  bool is_set(uint32_t n) const { return bitmap_is_set(&map, n); }

  bool is_set() const { return !bitmap_is_clear_all(&map); }

  bool is_prefix(uint32_t n) const { return bitmap_is_prefix(&map, n); }

  bool is_clear_all() const { return bitmap_is_clear_all(&map); }

  bool is_set_all() const { return bitmap_is_set_all(&map); }

  bool is_subset(const Bitmap& map2) const { return bitmap_is_subset(&map, &map2.map); }

  bool is_overlapping(const Bitmap& map2) const { return bitmap_is_overlapping(&map, &map2.map); }

  bool operator==(const Bitmap& map2) const { return bitmap_cmp(&map, &map2.map); }

  bool operator!=(const Bitmap& map2) const { return !bitmap_cmp(&map, &map2.map); }

  Bitmap operator&=(uint32_t n)

  {

    if (bitmap_is_set(&map, n))

    {

      bitmap_clear_all(&map);

      bitmap_set_bit(&map, n);

    }

    else

      bitmap_clear_all(&map);

    return *this;

  }

  Bitmap operator&=(const Bitmap& map2)

  {

    bitmap_intersect(&map, &map2.map);

    return *this;

  }

  Bitmap operator&(uint32_t n)

  {

    Bitmap bm(*this);

    bm&= n;

    return bm;

  }

  Bitmap operator&(const Bitmap& map2)

  {

    Bitmap bm(*this);

    bm&= map2;

    return bm;

  }

  Bitmap operator|=(uint32_t n)

  {

    bitmap_set_bit(&map, n);

    return *this;

  }

  Bitmap operator|=(const Bitmap& map2)

  {

    bitmap_union(&map, &map2.map);

  }

  Bitmap operator|(uint32_t n)

  {

    Bitmap bm(*this);

    bm|= n;

    return bm;

  }

  Bitmap operator|(const Bitmap& map2)

  {

    Bitmap bm(*this);

    bm|= map2;

    return bm;

  }

  Bitmap operator~()

  {

    Bitmap bm(*this);

    bitmap_invert(&bm.map);

    return bm;

  }

  char *print(char *buf) const

  {

    char *s=buf;

    const unsigned char *e=(unsigned char *)buffer, *b=e+sizeof(buffer)-1;

    while (!*b && b>e)

      b--;

    if ((*s=_dig_vec_upper[*b >> 4]) != '0')

        s++;

    *s++=_dig_vec_upper[*b & 15];

    while (--b>=e)

    {

      *s++=_dig_vec_upper[*b >> 4];

      *s++=_dig_vec_upper[*b & 15];

    }

    *s=0;

    return buf;

  }

  uint64_t to_uint64_t() const

  {

    if (sizeof(buffer) >= 8)

      return uint8korr(buffer);

    assert(sizeof(buffer) >= 4);

    return (uint64_t) uint4korr(buffer);

  }

};

template <> class Bitmap<64>

{

  uint64_t map;

public:

  Bitmap<64>() : map(0) { }

  explicit Bitmap<64>(uint32_t prefix_to_set) : map(0) { set_prefix(prefix_to_set); }

  void init() { }

  void init(uint32_t prefix_to_set) { set_prefix(prefix_to_set); }

  uint32_t length() const { return 64; }

  void set_bit(uint32_t n) { map|= ((uint64_t)1) << n; }

  void clear_bit(uint32_t n) { map&= ~(((uint64_t)1) << n); }

  void set_prefix(uint32_t n)

  {

    if (n >= length())

      set_all();

    else

      map= (((uint64_t)1) << n)-1;

  }

  void set_all() { map=~(uint64_t)0; }

  void clear_all() { map=(uint64_t)0; }

  void intersect(Bitmap<64>& map2) { map&= map2.map; }

  void intersect(uint64_t map2) { map&= map2; }

  void intersect_extended(uint64_t map2) { map&= map2; }

  void subtract(Bitmap<64>& map2) { map&= ~map2.map; }

  void merge(Bitmap<64>& map2) { map|= map2.map; }

  bool is_set(uint32_t n) const { return test(map & (((uint64_t)1) << n)); }

  bool is_prefix(uint32_t n) const { return map == (((uint64_t)1) << n)-1; }

  bool is_clear_all() const { return map == (uint64_t)0; }

  bool is_set_all() const { return map == ~(uint64_t)0; }

  bool is_subset(const Bitmap<64>& map2) const { return !(map & ~map2.map); }

  bool is_overlapping(const Bitmap<64>& map2) const { return (map & map2.map)!= 0; }

  bool operator==(const Bitmap<64>& map2) const { return map == map2.map; }

  char *print(char *buf) const { int64_t2str(map,buf,16); return buf; }

  uint64_t to_uint64_t() const { return map; }

};

typedef uint64_t table_map;          /* Used for table bits in join */

#if MAX_INDEXES <= 64

typedef Bitmap<64>  key_map;          /* Used for finding keys */

#else

typedef Bitmap<((MAX_INDEXES+7)/8*8)> key_map; /* Used for finding keys */

#endif

typedef uint32_t nesting_map;  /* Used for flags of nesting constructs */

/*

  Used to identify NESTED_JOIN structures within a join (applicable only to

  structures that have not been simplified away and embed more the one

  element)

*/

typedef uint64_t nested_join_map; /* Needed by sql_select.h and table.h */

/* useful constants */#

extern const key_map key_map_empty;

extern key_map key_map_full;          /* Should be threaded as const */

#endif /* _SQL_BITMAP_H_ */