Files
rxing/port_src/output/zxing/common/bit_array.rs
2022-08-12 16:58:30 -05:00

437 lines
13 KiB
Rust

/*
* Copyright 2007 ZXing authors
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
// package com::google::zxing::common;
/**
* <p>A simple, fast array of bits, represented compactly by an array of ints internally.</p>
*
* @author Sean Owen
*/
const EMPTY_BITS;
const LOAD_FACTOR: f32 = 0.75f;
#[derive(Cloneable)]
pub struct BitArray {
let mut bits: Vec<i32>;
let mut size: i32;
}
impl BitArray {
pub fn new() -> BitArray {
let .size = 0;
let .bits = EMPTY_BITS;
}
pub fn new( size: i32) -> BitArray {
let .size = size;
let .bits = ::make_array(size);
}
// For testing only
fn new( bits: &Vec<i32>, size: i32) -> BitArray {
let .bits = bits;
let .size = size;
}
pub fn get_size(&self) -> i32 {
return self.size;
}
pub fn get_size_in_bytes(&self) -> i32 {
return (self.size + 7) / 8;
}
fn ensure_capacity(&self, new_size: i32) {
if new_size > self.bits.len() * 32 {
let new_bits: Vec<i32> = ::make_array(Math::ceil(new_size / LOAD_FACTOR) as i32);
System::arraycopy(&self.bits, 0, &new_bits, 0, self.bits.len());
self.bits = new_bits;
}
}
/**
* @param i bit to get
* @return true iff bit i is set
*/
pub fn get(&self, i: i32) -> bool {
return (self.bits[i / 32] & (1 << (i & 0x1F))) != 0;
}
/**
* Sets bit i.
*
* @param i bit to set
*/
pub fn set(&self, i: i32) {
self.bits[i / 32] |= 1 << (i & 0x1F);
}
/**
* Flips bit i.
*
* @param i bit to set
*/
pub fn flip(&self, i: i32) {
self.bits[i / 32] ^= 1 << (i & 0x1F);
}
/**
* @param from first bit to check
* @return index of first bit that is set, starting from the given index, or size if none are set
* at or beyond this given index
* @see #getNextUnset(int)
*/
pub fn get_next_set(&self, from: i32) -> i32 {
if from >= self.size {
return self.size;
}
let bits_offset: i32 = from / 32;
let current_bits: i32 = self.bits[bits_offset];
// mask off lesser bits first
current_bits &= -(1 << (from & 0x1F));
while current_bits == 0 {
if bits_offset += 1 == self.bits.len() {
return self.size;
}
current_bits = self.bits[bits_offset];
}
let result: i32 = (bits_offset * 32) + Integer::number_of_trailing_zeros(current_bits);
return Math::min(result, self.size);
}
/**
* @param from index to start looking for unset bit
* @return index of next unset bit, or {@code size} if none are unset until the end
* @see #getNextSet(int)
*/
pub fn get_next_unset(&self, from: i32) -> i32 {
if from >= self.size {
return self.size;
}
let bits_offset: i32 = from / 32;
let current_bits: i32 = ~self.bits[bits_offset];
// mask off lesser bits first
current_bits &= -(1 << (from & 0x1F));
while current_bits == 0 {
if bits_offset += 1 == self.bits.len() {
return self.size;
}
current_bits = ~self.bits[bits_offset];
}
let result: i32 = (bits_offset * 32) + Integer::number_of_trailing_zeros(current_bits);
return Math::min(result, self.size);
}
/**
* Sets a block of 32 bits, starting at bit i.
*
* @param i first bit to set
* @param newBits the new value of the next 32 bits. Note again that the least-significant bit
* corresponds to bit i, the next-least-significant to i+1, and so on.
*/
pub fn set_bulk(&self, i: i32, new_bits: i32) {
self.bits[i / 32] = new_bits;
}
/**
* Sets a range of bits.
*
* @param start start of range, inclusive.
* @param end end of range, exclusive
*/
pub fn set_range(&self, start: i32, end: i32) {
if end < start || start < 0 || end > self.size {
throw IllegalArgumentException::new();
}
if end == start {
return;
}
// will be easier to treat this as the last actually set bit -- inclusive
end -= 1;
let first_int: i32 = start / 32;
let last_int: i32 = end / 32;
{
let mut i: i32 = first_int;
while i <= last_int {
{
let first_bit: i32 = if i > first_int { 0 } else { start & 0x1F };
let last_bit: i32 = if i < last_int { 31 } else { end & 0x1F };
// Ones from firstBit to lastBit, inclusive
let mask: i32 = (2 << last_bit) - (1 << first_bit);
self.bits[i] |= mask;
}
i += 1;
}
}
}
/**
* Clears all bits (sets to false).
*/
pub fn clear(&self) {
let max: i32 = self.bits.len();
{
let mut i: i32 = 0;
while i < max {
{
self.bits[i] = 0;
}
i += 1;
}
}
}
/**
* Efficient method to check if a range of bits is set, or not set.
*
* @param start start of range, inclusive.
* @param end end of range, exclusive
* @param value if true, checks that bits in range are set, otherwise checks that they are not set
* @return true iff all bits are set or not set in range, according to value argument
* @throws IllegalArgumentException if end is less than start or the range is not contained in the array
*/
pub fn is_range(&self, start: i32, end: i32, value: bool) -> bool {
if end < start || start < 0 || end > self.size {
throw IllegalArgumentException::new();
}
if end == start {
// empty range matches
return true;
}
// will be easier to treat this as the last actually set bit -- inclusive
end -= 1;
let first_int: i32 = start / 32;
let last_int: i32 = end / 32;
{
let mut i: i32 = first_int;
while i <= last_int {
{
let first_bit: i32 = if i > first_int { 0 } else { start & 0x1F };
let last_bit: i32 = if i < last_int { 31 } else { end & 0x1F };
// Ones from firstBit to lastBit, inclusive
let mask: i32 = (2 << last_bit) - (1 << first_bit);
// equals the mask, or we're looking for 0s and the masked portion is not all 0s
if (self.bits[i] & mask) != ( if value { mask } else { 0 }) {
return false;
}
}
i += 1;
}
}
return true;
}
pub fn append_bit(&self, bit: bool) {
self.ensure_capacity(self.size + 1);
if bit {
self.bits[self.size / 32] |= 1 << (self.size & 0x1F);
}
self.size += 1;
}
/**
* Appends the least-significant bits, from value, in order from most-significant to
* least-significant. For example, appending 6 bits from 0x000001E will append the bits
* 0, 1, 1, 1, 1, 0 in that order.
*
* @param value {@code int} containing bits to append
* @param numBits bits from value to append
*/
pub fn append_bits(&self, value: i32, num_bits: i32) {
if num_bits < 0 || num_bits > 32 {
throw IllegalArgumentException::new("Num bits must be between 0 and 32");
}
let next_size: i32 = self.size;
self.ensure_capacity(next_size + num_bits);
{
let num_bits_left: i32 = num_bits - 1;
while num_bits_left >= 0 {
{
if (value & (1 << num_bits_left)) != 0 {
self.bits[next_size / 32] |= 1 << (next_size & 0x1F);
}
next_size += 1;
}
num_bits_left -= 1;
}
}
self.size = next_size;
}
pub fn append_bit_array(&self, other: &BitArray) {
let other_size: i32 = other.size;
self.ensure_capacity(self.size + other_size);
{
let mut i: i32 = 0;
while i < other_size {
{
self.append_bit(&other.get(i));
}
i += 1;
}
}
}
pub fn xor(&self, other: &BitArray) {
if self.size != other.size {
throw IllegalArgumentException::new("Sizes don't match");
}
{
let mut i: i32 = 0;
while i < self.bits.len() {
{
// The last int could be incomplete (i.e. not have 32 bits in
// it) but there is no problem since 0 XOR 0 == 0.
self.bits[i] ^= other.bits[i];
}
i += 1;
}
}
}
/**
*
* @param bitOffset first bit to start writing
* @param array array to write into. Bytes are written most-significant byte first. This is the opposite
* of the internal representation, which is exposed by {@link #getBitArray()}
* @param offset position in array to start writing
* @param numBytes how many bytes to write
*/
pub fn to_bytes(&self, bit_offset: i32, array: &Vec<i8>, offset: i32, num_bytes: i32) {
{
let mut i: i32 = 0;
while i < num_bytes {
{
let the_byte: i32 = 0;
{
let mut j: i32 = 0;
while j < 8 {
{
if self.get(bit_offset) {
the_byte |= 1 << (7 - j);
}
bit_offset += 1;
}
j += 1;
}
}
array[offset + i] = the_byte as i8;
}
i += 1;
}
}
}
/**
* @return underlying array of ints. The first element holds the first 32 bits, and the least
* significant bit is bit 0.
*/
pub fn get_bit_array(&self) -> Vec<i32> {
return self.bits;
}
/**
* Reverses all bits in the array.
*/
pub fn reverse(&self) {
let new_bits: [i32; self.bits.len()] = [0; self.bits.len()];
// reverse all int's first
let mut len: i32 = (self.size - 1) / 32;
let old_bits_len: i32 = len + 1;
{
let mut i: i32 = 0;
while i < old_bits_len {
{
new_bits[len - i] = Integer::reverse(self.bits[i]);
}
i += 1;
}
}
// now correct the int's if the bit size isn't a multiple of 32
if self.size != old_bits_len * 32 {
let left_offset: i32 = old_bits_len * 32 - self.size;
let current_int: i32 = new_bits[0] >> /* >>> */ left_offset;
{
let mut i: i32 = 1;
while i < old_bits_len {
{
let next_int: i32 = new_bits[i];
current_int |= next_int << (32 - left_offset);
new_bits[i - 1] = current_int;
current_int = next_int >> /* >>> */ left_offset;
}
i += 1;
}
}
new_bits[old_bits_len - 1] = current_int;
}
self.bits = new_bits;
}
fn make_array( size: i32) -> Vec<i32> {
return : [i32; (size + 31) / 32] = [0; (size + 31) / 32];
}
pub fn equals(&self, o: &Object) -> bool {
if !(o instanceof BitArray) {
return false;
}
let other: BitArray = o as BitArray;
return self.size == other.size && Arrays::equals(&self.bits, other.bits);
}
pub fn hash_code(&self) -> i32 {
return 31 * self.size + Arrays::hash_code(&self.bits);
}
pub fn to_string(&self) -> String {
let result: StringBuilder = StringBuilder::new(self.size + (self.size / 8) + 1);
{
let mut i: i32 = 0;
while i < self.size {
{
if (i & 0x07) == 0 {
result.append(' ');
}
result.append( if self.get(i) { 'X' } else { '.' });
}
i += 1;
}
}
return result.to_string();
}
pub fn clone(&self) -> BitArray {
return BitArray::new(&self.bits.clone(), self.size);
}
}