woocommerce-pos / vendor_prefixed / chillerlan / php-qrcode / src / Common / BitBuffer.php

BitBuffer.php in WCPOS – Point of Sale (POS) plugin for WooCommerce 1.10.18, at vendor_prefixed/chillerlan/php-qrcode/src/Common/BitBuffer.php

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1	<?php
2
3	/**
4	* Class BitBuffer
5	*
6	* @created 25.11.2015
7	* @author Smiley <smiley@chillerlan.net>
8	* @copyright 2015 Smiley
9	* @license MIT
10	*/
11	namespace WCPOS\Vendor\chillerlan\QRCode\Common;
12
13	use WCPOS\Vendor\chillerlan\QRCode\QRCodeException;
14	use function count, floor, min;
15	/**
16	* Holds the raw binary data
17	*/
18	final class BitBuffer
19	{
20	/**
21	* The buffer content
22	*
23	* @var int[]
24	*/
25	private array $buffer;
26	/**
27	* Length of the content (bits)
28	*/
29	private int $length;
30	/**
31	* Read count (bytes)
32	*/
33	private int $bytesRead = 0;
34	/**
35	* Read count (bits)
36	*/
37	private int $bitsRead = 0;
38	/**
39	* BitBuffer constructor.
40	*
41	* @param int[] $bytes
42	*/
43	public function __construct(array $bytes = [])
44	{
45	$this->buffer = $bytes;
46	$this->length = count($this->buffer);
47	}
48	/**
49	* appends a sequence of bits
50	*/
51	public function put(int $bits, int $length) : self
52	{
53	for ($i = 0; $i < $length; $i++) {
54	$this->putBit(($bits >> $length - $i - 1 & 1) === 1);
55	}
56	return $this;
57	}
58	/**
59	* appends a single bit
60	*/
61	public function putBit(bool $bit) : self
62	{
63	$bufIndex = (int) floor($this->length / 8);
64	if (count($this->buffer) <= $bufIndex) {
65	$this->buffer[] = 0;
66	}
67	if ($bit === \true) {
68	$this->buffer[$bufIndex] \|= 0x80 >> $this->length % 8;
69	}
70	$this->length++;
71	return $this;
72	}
73	/**
74	* returns the current buffer length
75	*/
76	public function getLength() : int
77	{
78	return $this->length;
79	}
80	/**
81	* returns the buffer content
82	*
83	* to debug: array_map(fn($v) => sprintf('%08b', $v), $bitBuffer->getBuffer())
84	*/
85	public function getBuffer() : array
86	{
87	return $this->buffer;
88	}
89	/**
90	* @return int number of bits that can be read successfully
91	*/
92	public function available() : int
93	{
94	return 8 * ($this->length - $this->bytesRead) - $this->bitsRead;
95	}
96	/**
97	* @author Sean Owen, ZXing
98	*
99	* @param int $numBits number of bits to read
100	*
101	* @return int representing the bits read. The bits will appear as the least-significant bits of the int
102	* @throws \chillerlan\QRCode\QRCodeException if numBits isn't in [1,32] or more than is available
103	*/
104	public function read(int $numBits) : int
105	{
106	if ($numBits < 1 \|\| $numBits > $this->available()) {
107	throw new QRCodeException('invalid $numBits: ' . $numBits);
108	}
109	$result = 0;
110	// First, read remainder from current byte
111	if ($this->bitsRead > 0) {
112	$bitsLeft = 8 - $this->bitsRead;
113	$toRead = min($numBits, $bitsLeft);
114	$bitsToNotRead = $bitsLeft - $toRead;
115	$mask = 0xff >> 8 - $toRead << $bitsToNotRead;
116	$result = ($this->buffer[$this->bytesRead] & $mask) >> $bitsToNotRead;
117	$numBits -= $toRead;
118	$this->bitsRead += $toRead;
119	if ($this->bitsRead === 8) {
120	$this->bitsRead = 0;
121	$this->bytesRead++;
122	}
123	}
124	// Next read whole bytes
125	if ($numBits > 0) {
126	while ($numBits >= 8) {
127	$result = $result << 8 \| $this->buffer[$this->bytesRead] & 0xff;
128	$this->bytesRead++;
129	$numBits -= 8;
130	}
131	// Finally read a partial byte
132	if ($numBits > 0) {
133	$bitsToNotRead = 8 - $numBits;
134	$mask = 0xff >> $bitsToNotRead << $bitsToNotRead;
135	$result = $result << $numBits \| ($this->buffer[$this->bytesRead] & $mask) >> $bitsToNotRead;
136	$this->bitsRead += $numBits;
137	}
138	}
139	return $result;
140	}
141	/**
142	* Clears the buffer and resets the stats
143	*/
144	public function clear() : self
145	{
146	$this->buffer = [];
147	$this->length = 0;
148	return $this->rewind();
149	}
150	/**
151	* Resets the read-counters
152	*/
153	public function rewind() : self
154	{
155	$this->bytesRead = 0;
156	$this->bitsRead = 0;
157	return $this;
158	}
159	}
160