1#@!#!123s

: / opt / psa / admin / plib / modules / grafana / vendor / laminas / laminas-diactoros / src /
Filename : CallbackStream.php
back
<?php

declare (strict_types=1);
namespace PleskGrafana\Laminas\Diactoros;

use Psr\Http\Message\StreamInterface;
use Stringable;
use function array_key_exists;
use const SEEK_SET;
/**
 * Implementation of PSR HTTP streams
 */
class CallbackStream implements StreamInterface, Stringable
{
    /** @var callable|null */
    protected $callback;
    /**
     * @throws Exception\InvalidArgumentException
     */
    public function __construct(callable $callback)
    {
        $this->attach($callback);
    }
    /**
     * {@inheritdoc}
     */
    public function __toString() : string
    {
        return $this->getContents();
    }
    /**
     * {@inheritdoc}
     */
    public function close() : void
    {
        $this->callback = null;
    }
    /**
     * {@inheritdoc}
     *
     * @return null|callable
     */
    public function detach() : ?callable
    {
        $callback = $this->callback;
        $this->callback = null;
        return $callback;
    }
    /**
     * Attach a new callback to the instance.
     */
    public function attach(callable $callback) : void
    {
        $this->callback = $callback;
    }
    /**
     * {@inheritdoc}
     */
    public function getSize() : ?int
    {
        return null;
    }
    /**
     * {@inheritdoc}
     */
    public function tell() : int
    {
        throw Exception\UntellableStreamException::forCallbackStream();
    }
    /**
     * {@inheritdoc}
     */
    public function eof() : bool
    {
        return $this->callback === null;
    }
    /**
     * {@inheritdoc}
     */
    public function isSeekable() : bool
    {
        return \false;
    }
    /**
     * {@inheritdoc}
     */
    public function seek(int $offset, int $whence = SEEK_SET) : void
    {
        throw Exception\UnseekableStreamException::forCallbackStream();
    }
    /**
     * {@inheritdoc}
     */
    public function rewind() : void
    {
        throw Exception\UnrewindableStreamException::forCallbackStream();
    }
    /**
     * {@inheritdoc}
     */
    public function isWritable() : bool
    {
        return \false;
    }
    /**
     * {@inheritdoc}
     */
    public function write(string $string) : int
    {
        throw Exception\UnwritableStreamException::forCallbackStream();
    }
    /**
     * {@inheritdoc}
     */
    public function isReadable() : bool
    {
        return \false;
    }
    /**
     * {@inheritdoc}
     */
    public function read(int $length) : string
    {
        throw Exception\UnreadableStreamException::forCallbackStream();
    }
    /**
     * {@inheritdoc}
     */
    public function getContents() : string
    {
        $callback = $this->detach();
        $contents = $callback !== null ? $callback() : '';
        return (string) $contents;
    }
    /**
     * {@inheritdoc}
     */
    public function getMetadata(?string $key = null)
    {
        $metadata = ['eof' => $this->eof(), 'stream_type' => 'callback', 'seekable' => \false];
        if (null === $key) {
            return $metadata;
        }
        if (!array_key_exists($key, $metadata)) {
            return null;
        }
        return $metadata[$key];
    }
}