uSTL_2.3/include/ubitset.h

127 lines
6.6 KiB
C++

// This file is part of the uSTL library, an STL implementation.
//
// Copyright (c) 2005 by Mike Sharov <msharov@users.sourceforge.net>
// This file is free software, distributed under the MIT License.
#pragma once
#include "ustring.h"
#include "ufunction.h"
namespace ustl {
typedef uint32_t bitset_value_type;
void convert_to_bitstring (const bitset_value_type* v, size_t n, string& buf) noexcept;
void convert_from_bitstring (const string& buf, bitset_value_type* v, size_t n) noexcept;
/// \class bitset ubitset.h ustl.h
/// \ingroup Sequences
///
/// \brief bitset is a fixed-size block of memory with addressable bits.
///
/// Normally used for state flags; allows setting and unsetting of individual
/// bits as well as bitwise operations on the entire set. The interface is
/// most like that of unsigned integers, and is intended to be used as such.
/// If you were using begin() and end() functions in STL's bitset, you would
/// not be able to do the same thing here, because those functions return
/// host type iterators, not bits.
///
template <size_t Size>
class bitset {
public:
typedef bitset_value_type value_type;
typedef value_type* pointer;
typedef const value_type* const_pointer;
typedef pointer iterator;
typedef const_pointer const_iterator;
typedef size_t difference_type;
typedef size_t size_type;
typedef const bitset<Size>& rcself_t;
private:
static const size_t s_WordBits = BitsInType (value_type);
static const size_t s_nWords = Size / s_WordBits + ((Size % s_WordBits) != 0);
static const size_t s_nBits = s_nWords * s_WordBits;
private:
inline value_type& BitRef (uoff_t n) { assert (n < Size); return (m_Bits [n / s_WordBits]); }
inline value_type BitRef (uoff_t n) const { assert (n < Size); return (m_Bits [n / s_WordBits]); }
inline value_type Mask (uoff_t n) const { assert (n < Size); return (1 << (n % s_WordBits)); }
public:
inline bitset (value_type v = 0) { fill_n (m_Bits, s_nWords, 0); m_Bits[0] = v; }
inline bitset (const string& buf) { convert_from_bitstring (buf, m_Bits, s_nWords); }
inline void flip (uoff_t n) { BitRef(n) ^= Mask(n); }
inline void reset (void) { fill_n (m_Bits, s_nWords, 0); }
inline void clear (void) { fill_n (m_Bits, s_nWords, 0); }
inline void set (void) { fill_n (m_Bits, s_nWords, -1); }
inline bitset operator~ (void) const { bitset rv (*this); rv.flip(); return (rv); }
inline size_type size (void) const { return (Size); }
inline size_type capacity (void) const { return (s_nBits); }
inline bool test (uoff_t n) const { return (BitRef(n) & Mask(n)); }
inline bool operator[] (uoff_t n) const { return (test(n)); }
inline const_iterator begin (void) const { return (m_Bits); }
inline iterator begin (void) { return (m_Bits); }
inline const_iterator end (void) const { return (m_Bits + s_nWords); }
inline iterator end (void) { return (m_Bits + s_nWords); }
/// Returns the value_type with the equivalent bits. If size() > 1, you'll get only the first BitsInType(value_type) bits.
inline value_type to_value (void) const { return (m_Bits[0]); }
/// Flips all the bits in the set.
inline void flip (void) { transform (begin(), end(), begin(), bitwise_not<value_type>()); }
/// Sets or clears bit \p n.
inline void set (uoff_t n, bool val = true)
{
value_type& br (BitRef (n));
const value_type mask (Mask (n));
const value_type bOn (br | mask), bOff (br & ~mask);
br = val ? bOn : bOff;
}
// Sets the value of the bitrange \p first through \p last to the equivalent number of bits from \p v.
inline void set (uoff_t first, uoff_t DebugArg(last), value_type v)
{
assert (size_t (distance (first, last)) <= s_WordBits && "Bit ranges must be 32 bits or smaller");
assert (first / s_WordBits == last / s_WordBits && "Bit ranges can not cross dword (4 byte) boundary");
assert ((v & BitMask(value_type,distance(first,last))) == v && "The value is too large to fit in the given bit range");
BitRef(first) |= v << (first % s_WordBits);
}
/// Clears the bit \p n.
inline void reset (uoff_t n) { set (n, false); }
/// Returns a string with bits MSB "001101001..." LSB.
inline string to_string (void) const
{
string rv (Size, '0');
convert_to_bitstring (m_Bits, s_nWords, rv);
return (rv);
}
inline value_type at (uoff_t n) const { return (test(n)); }
/// Returns the value in bits \p first through \p last.
inline value_type at (uoff_t first, uoff_t last) const
{
assert (size_t (distance (first, last)) <= s_WordBits && "Bit ranges must be 32 bits or smaller");
assert (first / s_WordBits == last / s_WordBits && "Bit ranges can not cross dword (4 byte) boundary");
return ((BitRef(first) >> (first % s_WordBits)) & BitMask(value_type,distance(first, last)));
}
inline bool any (void) const { value_type sum = 0; foreach (const_iterator, i, *this) sum |= *i; return (sum); }
inline bool none (void) const { return (!any()); }
inline size_t count (void) const { size_t sum = 0; foreach (const_iterator, i, *this) sum += popcount(*i); return (sum); }
inline bool operator== (rcself_t v) const
{ return (s_nWords == 1 ? (m_Bits[0] == v.m_Bits[0]) : equal (begin(), end(), v.begin())); }
inline bitset operator& (rcself_t v) const
{ bitset<Size> result; transform (begin(), end(), v.begin(), result.begin(), bitwise_and<value_type>()); return (result); }
inline bitset operator| (rcself_t v) const
{ bitset<Size> result; transform (begin(), end(), v.begin(), result.begin(), bitwise_or<value_type>()); return (result); }
inline bitset operator^ (rcself_t v) const
{ bitset<Size> result; transform (begin(), end(), v.begin(), result.begin(), bitwise_xor<value_type>()); return (result); }
inline rcself_t operator&= (rcself_t v)
{ transform (begin(), end(), v.begin(), begin(), bitwise_and<value_type>()); return (*this); }
inline rcself_t operator|= (rcself_t v)
{ transform (begin(), end(), v.begin(), begin(), bitwise_or<value_type>()); return (*this); }
inline rcself_t operator^= (rcself_t v)
{ transform (begin(), end(), v.begin(), begin(), bitwise_xor<value_type>()); return (*this); }
inline void read (istream& is) { nr_container_read (is, *this); }
inline void write (ostream& os) const { nr_container_write (os, *this); }
inline void text_write (ostringstream& os) const { os << to_string(); }
inline size_t stream_size (void) const { return (sizeof(m_Bits)); }
private:
value_type m_Bits [s_nWords];
};
} // namespace ustl