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