1
|
|
|
<?php |
2
|
|
|
|
3
|
|
|
namespace BitWasp\Buffertools; |
4
|
|
|
|
5
|
|
|
class Buffertools |
6
|
|
|
{ |
7
|
|
|
/** |
8
|
|
|
* @param int $decimal |
9
|
|
|
* @return string |
10
|
|
|
* @throws \Exception |
11
|
|
|
*/ |
12
|
|
|
public static function numToVarIntBin($decimal) |
13
|
|
|
{ |
14
|
|
|
if ($decimal < 0xfd) { |
15
|
|
|
$bin = chr($decimal); |
16
|
|
|
} elseif ($decimal <= 0xffff) { |
17
|
|
|
// Uint16 |
18
|
|
|
$bin = pack("Cv", 0xfd, $decimal); |
19
|
|
|
} elseif ($decimal <= 0xffffffff) { |
20
|
|
|
// Uint32 |
21
|
|
|
$bin = pack("CV", 0xfe, $decimal); |
22
|
|
|
} else { |
23
|
|
|
// Todo, support for 64bit integers |
24
|
|
|
throw new \Exception('numToVarInt(): Integer too large'); |
25
|
|
|
} |
26
|
|
|
|
27
|
|
|
return $bin; |
28
|
|
|
} |
29
|
|
|
|
30
|
|
|
/** |
31
|
|
|
* Convert a decimal number into a VarInt Buffer |
32
|
|
|
* |
33
|
|
|
* @param integer $decimal |
34
|
|
|
* @return Buffer |
35
|
|
|
* @throws \Exception |
36
|
|
|
*/ |
37
|
|
|
public static function numToVarInt($decimal) |
38
|
|
|
{ |
39
|
|
|
return new Buffer(static::numToVarIntBin($decimal)); |
40
|
|
|
} |
41
|
|
|
|
42
|
|
|
/** |
43
|
|
|
* Flip byte order of this binary string. Accepts a string or Buffer, |
44
|
|
|
* and will return whatever type it was given. |
45
|
|
|
* |
46
|
|
|
* @param string|BufferInterface $bytes |
47
|
|
|
* @return string|BufferInterface |
48
|
|
|
*/ |
49
|
|
|
public static function flipBytes($bytes) |
50
|
|
|
{ |
51
|
|
|
$isBuffer = $bytes instanceof BufferInterface; |
52
|
|
|
if ($isBuffer) { |
53
|
|
|
$bytes = $bytes->getBinary(); |
54
|
|
|
} |
55
|
|
|
|
56
|
|
|
$flipped = implode('', array_reverse(str_split($bytes, 1))); |
57
|
|
|
if ($isBuffer) { |
58
|
|
|
$flipped = new Buffer($flipped); |
59
|
|
|
} |
60
|
|
|
|
61
|
|
|
return $flipped; |
62
|
|
|
} |
63
|
|
|
|
64
|
|
|
/** |
65
|
|
|
* @param BufferInterface $buffer1 |
66
|
|
|
* @param BufferInterface $buffer2 |
67
|
|
|
* @param int $size |
68
|
|
|
* @return BufferInterface |
69
|
|
|
*/ |
70
|
|
|
public static function concat(BufferInterface $buffer1, BufferInterface $buffer2, $size = null) |
71
|
|
|
{ |
72
|
|
|
return new Buffer($buffer1->getBinary() . $buffer2->getBinary(), $size); |
73
|
|
|
} |
74
|
|
|
|
75
|
|
|
/** |
76
|
|
|
* What if we don't have two buffers, or want to guard the types of the |
77
|
|
|
* sorting algorithm? |
78
|
|
|
* |
79
|
|
|
* The default behaviour should be, take a list of Buffers/SerializableInterfaces, and |
80
|
|
|
* sort their binary representation. |
81
|
|
|
* |
82
|
|
|
* If an anonymous function is provided, we completely defer the conversion of values to |
83
|
|
|
* Buffer to the $convertToBuffer callable. |
84
|
|
|
* |
85
|
|
|
* This is to allow anonymous functions which are responsible for converting the item to a buffer, |
86
|
|
|
* and which optionally type-hint the items in the array. |
87
|
|
|
* |
88
|
|
|
* @param array $items |
89
|
|
|
* @param callable $convertToBuffer |
90
|
|
|
* @return array |
91
|
|
|
*/ |
92
|
|
|
public static function sort(array $items, callable $convertToBuffer = null) |
93
|
|
|
{ |
94
|
|
|
if (null == $convertToBuffer) { |
95
|
|
|
$convertToBuffer = function ($value) { |
96
|
|
|
if ($value instanceof BufferInterface) { |
97
|
|
|
return $value; |
98
|
|
|
} |
99
|
|
|
if ($value instanceof SerializableInterface) { |
100
|
|
|
return $value->getBuffer(); |
101
|
|
|
} |
102
|
|
|
throw new \RuntimeException('Requested to sort unknown type'); |
103
|
|
|
}; |
104
|
|
|
} |
105
|
|
|
|
106
|
|
|
usort($items, function ($a, $b) use ($convertToBuffer) { |
107
|
|
|
$av = $convertToBuffer($a)->getBinary(); |
108
|
|
|
$bv = $convertToBuffer($b)->getBinary(); |
109
|
|
|
return $av == $bv ? 0 : $av > $bv ? 1 : -1; |
110
|
|
|
}); |
111
|
|
|
|
112
|
|
|
return $items; |
113
|
|
|
} |
114
|
|
|
} |
115
|
|
|
|