ok
Mini Shell
/* Copyright (c) 2003, 2013, Oracle and/or its affiliates
Copyright (c) 2009, 2013, Monty Program Ab.
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 */
/*
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
*/
#ifndef SQL_BITMAP_INCLUDED
#define SQL_BITMAP_INCLUDED
#include <my_sys.h>
#include <my_bitmap.h>
template <uint default_width> class Bitmap
{
MY_BITMAP map;
uint32 buffer[(default_width+31)/32];
public:
Bitmap() { init(); }
Bitmap(const Bitmap& from) { *this=from; }
explicit Bitmap(uint prefix_to_set) { init(prefix_to_set); }
void init() { my_bitmap_init(&map, buffer, default_width, 0); }
void init(uint prefix_to_set) { init(); set_prefix(prefix_to_set); }
uint length() const { return default_width; }
Bitmap& operator=(const Bitmap& map2)
{
init();
memcpy(buffer, map2.buffer, sizeof(buffer));
return *this;
}
void set_bit(uint n) { bitmap_set_bit(&map, n); }
void clear_bit(uint n) { bitmap_clear_bit(&map, n); }
void set_prefix(uint 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(ulonglong map2buff)
{
// Use a spearate temporary buffer, as bitmap_init() clears all the bits.
ulonglong buf2;
MY_BITMAP map2;
my_bitmap_init(&map2, (uint32 *) &buf2, sizeof(ulonglong) * 8, 0);
// Store the original bits.
if (sizeof(ulonglong) >= 8)
{
int8store(const_cast<uchar *>(static_cast<uchar *>
(static_cast<void *>(&buf2))),
map2buff);
}
else
{
DBUG_ASSERT(sizeof(buffer) >= 4);
int4store(const_cast<uchar *>(static_cast<uchar *>
(static_cast<void *>(&buf2))),
static_cast<uint32>(map2buff));
}
bitmap_intersect(&map, &map2);
}
/* Use highest bit for all bits above sizeof(ulonglong)*8. */
void intersect_extended(ulonglong map2buff)
{
intersect(map2buff);
if (map.n_bits > sizeof(ulonglong) * 8)
bitmap_set_above(&map, sizeof(ulonglong),
MY_TEST(map2buff & (1LL << (sizeof(ulonglong) * 8 - 1))));
}
void subtract(Bitmap& map2) { bitmap_subtract(&map, &map2.map); }
void merge(Bitmap& map2) { bitmap_union(&map, &map2.map); }
bool is_set(uint n) const { return bitmap_is_set(&map, n); }
bool is_prefix(uint 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 !(*this == map2); }
char *print(char *buf) const
{
char *s=buf;
const uchar *e=(uchar *)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;
}
ulonglong to_ulonglong() const
{
if (sizeof(buffer) >= 8)
return uint8korr(static_cast<const uchar *>
(static_cast<const void *>(buffer)));
DBUG_ASSERT(sizeof(buffer) >= 4);
return (ulonglong)
uint4korr(static_cast<const uchar *>
(static_cast<const void *>(buffer)));
}
uint bits_set()
{
return bitmap_bits_set(&map);
}
class Iterator
{
Bitmap ↦
uint no;
public:
Iterator(Bitmap<default_width> &map2): map(map2), no(0) {}
int operator++(int) {
if (no == default_width) return BITMAP_END;
while (!map.is_set(no))
{
if ((++no) == default_width) return BITMAP_END;
}
return no ++;
}
enum { BITMAP_END= default_width };
};
};
/* An iterator to quickly walk over bits in ulonglong bitmap. */
class Table_map_iterator
{
ulonglong bmp;
uint no;
public:
Table_map_iterator(ulonglong t) : bmp(t), no(0) {}
uint next_bit()
{
static const uchar last_bit[16]= {32, 0, 1, 0,
2, 0, 1, 0,
3, 0, 1, 0,
2, 0, 1, 0};
uint bit;
while ((bit= last_bit[bmp & 0xF]) == 32)
{
no += 4;
bmp= bmp >> 4;
if (!bmp)
return BITMAP_END;
}
bmp &= ~(1ULL << bit);
return no + bit;
}
uint operator++(int) { return next_bit(); }
enum { BITMAP_END= 64 };
};
template <> class Bitmap<64>
{
ulonglong map;
public:
Bitmap<64>() { }
explicit Bitmap<64>(uint prefix_to_set) { set_prefix(prefix_to_set); }
void init() { }
void init(uint prefix_to_set) { set_prefix(prefix_to_set); }
uint length() const { return 64; }
void set_bit(uint n) { map|= ((ulonglong)1) << n; }
void clear_bit(uint n) { map&= ~(((ulonglong)1) << n); }
void set_prefix(uint n)
{
if (n >= length())
set_all();
else
map= (((ulonglong)1) << n)-1;
}
void set_all() { map=~(ulonglong)0; }
void clear_all() { map=(ulonglong)0; }
void intersect(Bitmap<64>& map2) { map&= map2.map; }
void intersect(ulonglong map2) { map&= map2; }
void intersect_extended(ulonglong map2) { map&= map2; }
void subtract(Bitmap<64>& map2) { map&= ~map2.map; }
void merge(Bitmap<64>& map2) { map|= map2.map; }
bool is_set(uint n) const { return MY_TEST(map & (((ulonglong) 1) << n)); }
bool is_prefix(uint n) const { return map == (((ulonglong)1) << n)-1; }
bool is_clear_all() const { return map == (ulonglong)0; }
bool is_set_all() const { return map == ~(ulonglong)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 {
longlong2str(longlong(map), buf, 16);
return buf;
}
ulonglong to_ulonglong() const { return map; }
class Iterator : public Table_map_iterator
{
public:
Iterator(Bitmap<64> &map2) : Table_map_iterator(map2.map) {}
};
uint bits_set()
{
//TODO: use my_count_bits()
uint res= 0, i= 0;
for (; i < 64 ; i++)
{
if (map & ((ulonglong)1<<i))
res++;
}
return res;
}
};
#endif /* SQL_BITMAP_INCLUDED */
Zerion Mini Shell 1.0