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See Release Notes
Long Term Support Release

  • Bug fixes for general core bugs in 4.1.x will end 13 November 2023 (12 months).
  • Bug fixes for security issues in 4.1.x will end 10 November 2025 (36 months).
  • PHP version: minimum PHP 7.4.0 Note: minimum PHP version has increased since Moodle 4.0. PHP 8.0.x is supported too.
<?php
declare(strict_types=1);

namespace ZipStream;

use Psr\Http\Message\StreamInterface;
use RuntimeException;

/**
 * Describes a data stream.
 *
 * Typically, an instance will wrap a PHP stream; this interface provides
 * a wrapper around the most common operations, including serialization of
 * the entire stream to a string.
 */
class Stream implements StreamInterface
{
    protected $stream;

    public function __construct($stream)
    {
        $this->stream = $stream;
    }

    /**
     * Closes the stream and any underlying resources.
     *
     * @return void
     */
    public function close(): void
    {
        if (is_resource($this->stream)) {
            fclose($this->stream);
        }
        $this->detach();
    }

    /**
     * Separates any underlying resources from the stream.
     *
     * After the stream has been detached, the stream is in an unusable state.
     *
     * @return resource|null Underlying PHP stream, if any
     */
    public function detach()
    {
        $result = $this->stream;
        $this->stream = null;
        return $result;
    }

    /**
     * Reads all data from the stream into a string, from the beginning to end.
     *
     * This method MUST attempt to seek to the beginning of the stream before
     * reading data and read the stream until the end is reached.
     *
     * Warning: This could attempt to load a large amount of data into memory.
     *
     * This method MUST NOT raise an exception in order to conform with PHP's
     * string casting operations.
     *
     * @see http://php.net/manual/en/language.oop5.magic.php#object.tostring
     * @return string
     */
    public function __toString(): string
    {
        try {
            $this->seek(0);
< } catch (\RuntimeException $e) {}
> } catch (RuntimeException $e) {}
return (string) stream_get_contents($this->stream); } /** * Seek to a position in the stream. * * @link http://www.php.net/manual/en/function.fseek.php * @param int $offset Stream offset * @param int $whence Specifies how the cursor position will be calculated * based on the seek offset. Valid values are identical to the built-in * PHP $whence values for `fseek()`. SEEK_SET: Set position equal to * offset bytes SEEK_CUR: Set position to current location plus offset * SEEK_END: Set position to end-of-stream plus offset.
< * @throws \RuntimeException on failure.
> * @throws RuntimeException on failure.
*/ public function seek($offset, $whence = SEEK_SET): void { if (!$this->isSeekable()) { throw new RuntimeException; } if (fseek($this->stream, $offset, $whence) !== 0) { throw new RuntimeException; } } /** * Returns whether or not the stream is seekable. * * @return bool */ public function isSeekable(): bool { return (bool)$this->getMetadata('seekable'); } /** * Get stream metadata as an associative array or retrieve a specific key. * * The keys returned are identical to the keys returned from PHP's * stream_get_meta_data() function. * * @link http://php.net/manual/en/function.stream-get-meta-data.php * @param string $key Specific metadata to retrieve. * @return array|mixed|null Returns an associative array if no key is * provided. Returns a specific key value if a key is provided and the * value is found, or null if the key is not found. */ public function getMetadata($key = null) { $metadata = stream_get_meta_data($this->stream); return $key !== null ? @$metadata[$key] : $metadata; } /** * Get the size of the stream if known. * * @return int|null Returns the size in bytes if known, or null if unknown. */ public function getSize(): ?int { $stats = fstat($this->stream); return $stats['size']; } /** * Returns the current position of the file read/write pointer * * @return int Position of the file pointer
< * @throws \RuntimeException on error.
> * @throws RuntimeException on error.
*/ public function tell(): int { $position = ftell($this->stream); if ($position === false) { throw new RuntimeException; } return $position; } /** * Returns true if the stream is at the end of the stream. * * @return bool */ public function eof(): bool { return feof($this->stream); } /** * Seek to the beginning of the stream. * * If the stream is not seekable, this method will raise an exception; * otherwise, it will perform a seek(0). * * @see seek() * @link http://www.php.net/manual/en/function.fseek.php
< * @throws \RuntimeException on failure.
> * @throws RuntimeException on failure.
*/ public function rewind(): void { $this->seek(0); } /** * Write data to the stream. * * @param string $string The string that is to be written. * @return int Returns the number of bytes written to the stream.
< * @throws \RuntimeException on failure.
> * @throws RuntimeException on failure.
*/ public function write($string): int { if (!$this->isWritable()) { throw new RuntimeException; } if (fwrite($this->stream, $string) === false) { throw new RuntimeException; } return \mb_strlen($string); } /** * Returns whether or not the stream is writable. * * @return bool */ public function isWritable(): bool {
< return preg_match('/[waxc+]/', $this->getMetadata('mode')) === 1;
> $mode = $this->getMetadata('mode'); > if (!is_string($mode)) { > throw new RuntimeException('Could not get stream mode from metadata!'); > } > return preg_match('/[waxc+]/', $mode) === 1;
} /** * Read data from the stream. * * @param int $length Read up to $length bytes from the object and return * them. Fewer than $length bytes may be returned if underlying stream * call returns fewer bytes. * @return string Returns the data read from the stream, or an empty string * if no bytes are available. * @throws \RuntimeException if an error occurs. */ public function read($length): string { if (!$this->isReadable()) { throw new RuntimeException; } $result = fread($this->stream, $length); if ($result === false) { throw new RuntimeException; } return $result; } /** * Returns whether or not the stream is readable. * * @return bool */ public function isReadable(): bool {
< return preg_match('/[r+]/', $this->getMetadata('mode')) === 1;
> $mode = $this->getMetadata('mode'); > if (!is_string($mode)) { > throw new RuntimeException('Could not get stream mode from metadata!'); > } > return preg_match('/[r+]/', $mode) === 1;
} /** * Returns the remaining contents in a string * * @return string * @throws \RuntimeException if unable to read or an error occurs while * reading. */ public function getContents(): string { if (!$this->isReadable()) { throw new RuntimeException; } $result = stream_get_contents($this->stream); if ($result === false) { throw new RuntimeException; } return $result; } }