Proyectos de Subversion Moodle

Rev

| Ultima modificación | Ver Log |

Rev Autor Línea Nro. Línea
1 efrain 1 
<?php
2 
 
3 
declare(strict_types=1);
4 
 
5 
namespace GuzzleHttp\Psr7;
6 
 
7 
use Psr\Http\Message\StreamInterface;
8 
 
9 
/**
10 
 * Provides a buffer stream that can be written to to fill a buffer, and read
11 
 * from to remove bytes from the buffer.
12 
 *
13 
 * This stream returns a "hwm" metadata value that tells upstream consumers
14 
 * what the configured high water mark of the stream is, or the maximum
15 
 * preferred size of the buffer.
16 
 */
17 
final class BufferStream implements StreamInterface
18 
{
19 
    /** @var int */
20 
    private $hwm;
21 
 
22 
    /** @var string */
23 
    private $buffer = '';
24 
 
25 
    /**
26 
     * @param int $hwm High water mark, representing the preferred maximum
27 
     *                 buffer size. If the size of the buffer exceeds the high
28 
     *                 water mark, then calls to write will continue to succeed
29 
     *                 but will return 0 to inform writers to slow down
30 
     *                 until the buffer has been drained by reading from it.
31 
     */
32 
    public function __construct(int $hwm = 16384)
33 
    {
34 
        $this->hwm = $hwm;
35 
    }
36 
 
37 
    public function __toString(): string
38 
    {
39 
        return $this->getContents();
40 
    }
41 
 
42 
    public function getContents(): string
43 
    {
44 
        $buffer = $this->buffer;
45 
        $this->buffer = '';
46 
 
47 
        return $buffer;
48 
    }
49 
 
50 
    public function close(): void
51 
    {
52 
        $this->buffer = '';
53 
    }
54 
 
55 
    public function detach()
56 
    {
57 
        $this->close();
58 
 
59 
        return null;
60 
    }
61 
 
62 
    public function getSize(): ?int
63 
    {
64 
        return strlen($this->buffer);
65 
    }
66 
 
67 
    public function isReadable(): bool
68 
    {
69 
        return true;
70 
    }
71 
 
72 
    public function isWritable(): bool
73 
    {
74 
        return true;
75 
    }
76 
 
77 
    public function isSeekable(): bool
78 
    {
79 
        return false;
80 
    }
81 
 
82 
    public function rewind(): void
83 
    {
84 
        $this->seek(0);
85 
    }
86 
 
87 
    public function seek($offset, $whence = SEEK_SET): void
88 
    {
89 
        throw new \RuntimeException('Cannot seek a BufferStream');
90 
    }
91 
 
92 
    public function eof(): bool
93 
    {
94 
        return strlen($this->buffer) === 0;
95 
    }
96 
 
97 
    public function tell(): int
98 
    {
99 
        throw new \RuntimeException('Cannot determine the position of a BufferStream');
100 
    }
101 
 
102 
    /**
103 
     * Reads data from the buffer.
104 
     */
105 
    public function read($length): string
106 
    {
107 
        $currentLength = strlen($this->buffer);
108 
 
109 
        if ($length >= $currentLength) {
110 
            // No need to slice the buffer because we don't have enough data.
111 
            $result = $this->buffer;
112 
            $this->buffer = '';
113 
        } else {
114 
            // Slice up the result to provide a subset of the buffer.
115 
            $result = substr($this->buffer, 0, $length);
116 
            $this->buffer = substr($this->buffer, $length);
117 
        }
118 
 
119 
        return $result;
120 
    }
121 
 
122 
    /**
123 
     * Writes data to the buffer.
124 
     */
125 
    public function write($string): int
126 
    {
127 
        $this->buffer .= $string;
128 
 
129 
        if (strlen($this->buffer) >= $this->hwm) {
130 
            return 0;
131 
        }
132 
 
133 
        return strlen($string);
134 
    }
135 
 
136 
    /**
137 
     * {@inheritdoc}
138 
     *
139 
     * @return mixed
140 
     */
141 
    public function getMetadata($key = null)
142 
    {
143 
        if ($key === 'hwm') {
144 
            return $this->hwm;
145 
        }
146 
 
147 
        return $key ? null : [];
148 
    }
149 
}