/**
* Returns an abstract of the file content.
*
* @return string
*/
public function getContentPreview()
{
if ($this->contentPreview === null) {
$this->contentPreview = '';
if (ATTACHMENT_ENABLE_CONTENT_PREVIEW && !$this->isBinary && $this->attachmentSize != 0) {
try {
$file = new File(WCF_DIR . 'attachments/attachment-' . $this->attachmentID, 'rb');
$this->contentPreview = $file->read(2003);
$file->close();
if (CHARSET == 'UTF-8') {
if (!StringUtil::isASCII($this->contentPreview) && !StringUtil::isUTF8($this->contentPreview)) {
$this->contentPreview = StringUtil::convertEncoding('ISO-8859-1', CHARSET, $this->contentPreview);
}
$this->contentPreview = StringUtil::substring($this->contentPreview, 0, 500);
if (strlen($this->contentPreview) < $file->filesize()) {
$this->contentPreview .= '...';
}
} else {
if (StringUtil::isUTF8($this->contentPreview)) {
$this->contentPreview = '';
} else {
$this->contentPreview = StringUtil::substring($this->contentPreview, 0, 500);
if ($file->filesize() > 500) {
$this->contentPreview .= '...';
}
}
}
} catch (Exception $e) {
}
// ignore errors
}
}
return $this->contentPreview;
}
/**
* Returns an abstract of the file content.
*
* @param array $data
* @return string
*/
protected static function getContentPreview($data)
{
if (!ATTACHMENT_ENABLE_CONTENT_PREVIEW || $data['isBinary'] || $data['attachmentSize'] == 0) {
return '';
}
$content = '';
try {
$file = new File(WCF_DIR . 'attachments/attachment-' . $data['attachmentID'], 'rb');
$content = $file->read(2003);
$file->close();
if (CHARSET == 'UTF-8') {
if (!StringUtil::isASCII($content) && !StringUtil::isUTF8($content)) {
$content = StringUtil::convertEncoding('ISO-8859-1', CHARSET, $content);
}
$content = StringUtil::substring($content, 0, 500);
if (strlen($content) < $file->filesize()) {
$content .= '...';
}
} else {
if (StringUtil::isUTF8($content)) {
return '';
}
$content = StringUtil::substring($content, 0, 500);
if ($file->filesize() > 500) {
$content .= '...';
}
}
} catch (Exception $e) {
}
// ignore errors
return $content;
}
/**
* Determines whether a file is text or binary by checking the first few bytes in the file.
* The exact number of bytes is system dependent, but it is typically several thousand.
* If every byte in that part of the file is non-null, considers the file to be text;
* otherwise it considers the file to be binary.
*
* @param string $file
* @return boolean
*/
public static function isBinary($file)
{
// open file
$file = new File($file, 'rb');
// get block size
$stat = $file->stat();
$blockSize = $stat['blksize'];
if ($blockSize < 0) {
$blockSize = 1024;
}
if ($blockSize > $file->filesize()) {
$blockSize = $file->filesize();
}
if ($blockSize <= 0) {
return false;
}
// get bytes
$block = $file->read($blockSize);
return strlen($block) == 0 || preg_match_all('/\\x00/', $block, $match) > 0;
}
