bsnes/purify/nall/bitarray.hpp

80 lines
1.8 KiB
C++
Executable File

#ifndef NALL_BITARRAY_HPP
#define NALL_BITARRAY_HPP
#include <nall/stdint.hpp>
//statically-sized bit array
//no bounds-checking on read/write
//packed into uint8_t array (8 bits per byte)
namespace nall {
struct bitarray {
uint8_t *pool;
unsigned poolsize;
uint8_t* data() { return pool; }
const uint8_t* data() const { return pool; }
unsigned size() const { return poolsize; }
unsigned bytesize() const { return (poolsize >> 3) + ((poolsize & 7) > 0); }
void reset() {
if(pool) free(pool);
pool = nullptr;
poolsize = 0u;
}
void resize(unsigned allocsize) {
if(allocsize == poolsize) return;
pool = (uint8_t*)realloc(pool, allocsize);
poolsize = allocsize;
}
bool operator[](unsigned offset) const {
return pool[offset >> 3] & (0x80 >> (offset & 7));
}
void set() {
memset(pool, 0xff, (poolsize >> 3) + ((poolsize & 7) > 0));
}
void set(unsigned offset) {
pool[offset >> 3] |= 0x80 >> (offset & 7);
}
void clear() {
memset(pool, 0, (poolsize >> 3) + ((poolsize & 7) > 0));
}
void clear(unsigned offset) {
pool[offset >> 3] &=~0x80 >> (offset & 7);
}
void set(unsigned offset, bool data) {
data ? set(offset) : clear(offset);
}
struct bit {
bitarray &array;
unsigned offset;
operator bool() const { return const_cast<const bitarray&>(array)[offset]; }
bit& operator=(bool data) { array.set(offset, data); return *this; }
bit& operator=(const bit& data) { return operator=((bool)data); }
bit(bitarray &array, unsigned offset) : array(array), offset(offset) {}
};
bit operator[](unsigned offset) {
return bit(*this, offset);
}
bitarray() : pool(nullptr), poolsize(0u) {}
bitarray(unsigned allocsize) {
pool = (uint8_t*)malloc((allocsize >> 3) + ((allocsize & 7) > 0));
poolsize = allocsize;
}
};
}
#endif