public function addContent($content) { $freeBufferLength = $this->chunkSize - StringHelper::byteLength($this->buffer); $contentLength = StringHelper::byteLength($content); if ($contentLength > $freeBufferLength) { $this->buffer .= StringHelper::byteSubstr($content, 0, $freeBufferLength); $this->flushBuffer(true); return $this->addContent(StringHelper::byteSubstr($content, $freeBufferLength)); } else { $this->buffer .= $content; $this->flushBuffer(); } return $this; }