* * For the full copyright and license information, please view the LICENSE * file that was distributed with this source code. */ class MWP_Stream_Limit implements MWP_Stream_Interface { /** * @var MWP_Stream_Interface */ private $stream; /** * @var int */ private $offset = 0; /** * @var int */ private $limit = -1; public function __construct(MWP_Stream_Interface $stream, $offset = 0, $limit = -1) { $this->stream = $stream; $this->setOffset($offset); $this->limit = $limit; } /** * {@inheritdoc} */ public function eof() { // Always return true if the underlying stream is EOF if ($this->stream->eof()) { return true; } // No limit and the underlying stream is not at EOF if ($this->limit == -1) { return false; } $tell = $this->stream->tell(); if ($tell === false) { return false; } return $tell >= $this->offset + $this->limit; } /** * {@inheritdoc} */ public function read($length) { if ($this->limit == -1) { return $this->stream->read($length); } // Check if the current position is less than the total allowed // bytes + original offset $remaining = ($this->offset + $this->limit) - $this->stream->tell(); if ($remaining > 0) { // Only return the amount of requested data, ensuring that the byte // limit is not exceeded return $this->stream->read(min($remaining, $length)); } else { return false; } } /** * {@inheritdoc} */ public function setOffset($offset) { $current = $this->stream->tell(); if ($current !== $offset) { // If the stream cannot seek to the offset position, then read to it if (!$this->stream->seek($offset)) { $this->stream->read($offset - $current); } } $this->offset = $offset; return $this; } /** * {@inheritdoc} */ public function tell() { return $this->stream->tell() - $this->offset; } /** * {@inheritdoc} */ public function isSeekable() { return $this->stream->isSeekable(); } /** * {@inheritdoc} */ public function seek($offset, $whence = SEEK_SET) { if ($whence !== SEEK_SET || $offset < 0) { return false; } $offset += $this->offset; if ($this->limit !== -1) { if ($offset > $this->offset + $this->limit) { $offset = $this->offset + $this->limit; } } return $this->stream->seek($offset); } /** * {@inheritdoc} */ public function close() { $this->stream->close(); } public function __toString() { $buffer = ''; while (!$this->eof()) { $buffer .= $this->read(1048576); } return $buffer; } }