Files
2025-08-02 18:35:47 +08:00

133 lines
3.5 KiB
Objective-C

/*
* Copyright 2012 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.
*/
@class ZXByteArray, ZXIntArray;
/**
* A simple, fast array of bits, represented compactly by an array of ints internally.
*/
@interface ZXBitArray : NSObject <NSCopying>
/**
* @return underlying array of ints. The first element holds the first 32 bits, and the least
* significant bit is bit 0.
*/
@property (nonatomic, assign, readonly) int32_t *bits;
@property (nonatomic, assign, readonly) int size;
- (id)initWithSize:(int)size;
- (int)sizeInBytes;
/**
* @param i bit to get
* @return true iff bit i is set
*/
- (BOOL)get:(int)i;
/**
* Sets bit i.
*
* @param i bit to set
*/
- (void)set:(int)i;
/**
* Flips bit i.
*
* @param i bit to set
*/
- (void)flip:(int)i;
/**
* @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
*/
- (int)nextSet:(int)from;
- (int)nextUnset:(int)from;
/**
* 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.
*/
- (void)setBulk:(int)i newBits:(int32_t)newBits;
/**
* Sets a range of bits.
*
* @param start start of range, inclusive.
* @param end end of range, exclusive
*/
- (void)setRange:(int)start end:(int)end;
/**
* Clears all bits (sets to false).
*/
- (void)clear;
/**
* 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 NSInvalidArgumentException if end is less than or equal to start
*/
- (BOOL)isRange:(int)start end:(int)end value:(BOOL)value;
- (void)appendBit:(BOOL)bit;
/**
* 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.
*/
- (void)appendBits:(int32_t)value numBits:(int)numBits;
- (void)appendBitArray:(ZXBitArray *)other;
- (void)xor:(ZXBitArray *)other;
/**
*
* @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
*/
- (void)toBytes:(int)bitOffset array:(ZXByteArray *)array offset:(int)offset numBytes:(int)numBytes;
/**
* @return underlying array of ints. The first element holds the first 32 bits, and the least
* significant bit is bit 0.
*/
- (ZXIntArray *)bitArray;
/**
* Reverses all bits in the array.
*/
- (void)reverse;
@end