#ifndef _SQL_BITMAP_H_ #define _SQL_BITMAP_H_ /* Copyright (C) 2003 MySQL 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 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 */ #include template 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() { 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) { MY_BITMAP map2; bitmap_init(&map2, (uint32 *)&map2buff, sizeof(ulonglong)*8, 0); 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(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); } my_bool is_set(uint n) const { return bitmap_is_set(&map, n); } my_bool is_set() const { return !bitmap_is_clear_all(&map); } my_bool is_prefix(uint n) const { return bitmap_is_prefix(&map, n); } my_bool is_clear_all() const { return bitmap_is_clear_all(&map); } my_bool is_set_all() const { return bitmap_is_set_all(&map); } my_bool is_subset(const Bitmap& map2) const { return bitmap_is_subset(&map, &map2.map); } my_bool is_overlapping(const Bitmap& map2) const { return bitmap_is_overlapping(&map, &map2.map); } my_bool operator==(const Bitmap& map2) const { return bitmap_cmp(&map, &map2.map); } my_bool operator!=(const Bitmap& map2) const { return !bitmap_cmp(&map, &map2.map); } Bitmap operator&=(uint 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&(uint n) { Bitmap bm(*this); bm&= n; return bm; } Bitmap operator&(const Bitmap& map2) { Bitmap bm(*this); bm&= map2; return bm; } Bitmap operator|=(uint n) { bitmap_set_bit(&map, n); return *this; } Bitmap operator|=(const Bitmap& map2) { bitmap_union(&map, &map2.map); } Bitmap operator|(uint 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 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(buffer); DBUG_ASSERT(sizeof(buffer) >= 4); return (ulonglong) uint4korr(buffer); } }; template <> class Bitmap<64> { ulonglong map; public: Bitmap<64>() { map= 0; } 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; } my_bool is_set(uint n) const { return test(map & (((ulonglong)1) << n)); } my_bool is_prefix(uint n) const { return map == (((ulonglong)1) << n)-1; } my_bool is_clear_all() const { return map == (ulonglong)0; } my_bool is_set_all() const { return map == ~(ulonglong)0; } my_bool is_subset(const Bitmap<64>& map2) const { return !(map & ~map2.map); } my_bool is_overlapping(const Bitmap<64>& map2) const { return (map & map2.map)!= 0; } my_bool operator==(const Bitmap<64>& map2) const { return map == map2.map; } char *print(char *buf) const { longlong2str(map,buf,16); return buf; } ulonglong to_ulonglong() const { return map; } }; /* An iterator to quickly walk over bits in unlonglong bitmap. */ class Table_map_iterator { ulonglong bmp; uint no; public: Table_map_iterator(ulonglong t) : bmp(t), no(0) {} int next_bit() { static const char 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 &= ~(1 << bit); return no + bit; } enum { BITMAP_END= 64 }; }; #if 0 void print_bits(table_map bmp) { Table_map_iterator it(bmp); int i, first= 1; fprintf(stderr, "0x%llx = ", bmp); while ((i= it.next_bit()) != Table_map_iterator::BITMAP_END) { fprintf(stderr, " %s 2^%d", (first?"":"+"), i); if (first) first= 0; } fprintf(stderr, "\n"); } int main() { print_bits(1024); print_bits(3); print_bits(0xF); print_bits(0xF0); print_bits(35); print_bits(1LL<<63); print_bits(0); print_bits(-1LL); } #endif #endif /* _SQL_BITMAP_H_ */