You cannot select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
roundcubemail/plugins/managesieve/lib/rcube_sieve_script.php

1074 lines
35 KiB
PHP

<?php
/**
* Class for operations on Sieve scripts
*
* Copyright (C) 2008-2011, The Roundcube Dev Team
* Copyright (C) 2011, Kolab Systems AG
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2
* as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*
* $Id$
*
*/
class rcube_sieve_script
{
public $content = array(); // script rules array
private $vars = array(); // "global" variables
private $prefix = ''; // script header (comments)
private $supported = array( // Sieve extensions supported by class
'fileinto', // RFC5228
'envelope', // RFC5228
'reject', // RFC5429
'ereject', // RFC5429
'copy', // RFC3894
'vacation', // RFC5230
'relational', // RFC3431
'regex', // draft-ietf-sieve-regex-01
'imapflags', // draft-melnikov-sieve-imapflags-06
'imap4flags', // RFC5232
'include', // draft-ietf-sieve-include-12
'variables', // RFC5229
'body', // RFC5173
'subaddress', // RFC5233
// @TODO: enotify/notify, spamtest+virustest, mailbox, date
);
/**
* Object constructor
*
* @param string Script's text content
* @param array List of capabilities supported by server
*/
public function __construct($script, $capabilities=array())
{
$capabilities = array_map('strtolower', (array) $capabilities);
// disable features by server capabilities
if (!empty($capabilities)) {
foreach ($this->supported as $idx => $ext) {
if (!in_array($ext, $capabilities)) {
unset($this->supported[$idx]);
}
}
}
// Parse text content of the script
$this->_parse_text($script);
}
/**
* Adds rule to the script (at the end)
*
* @param string Rule name
* @param array Rule content (as array)
*
* @return int The index of the new rule
*/
public function add_rule($content)
{
// TODO: check this->supported
array_push($this->content, $content);
return sizeof($this->content)-1;
}
public function delete_rule($index)
{
if(isset($this->content[$index])) {
unset($this->content[$index]);
return true;
}
return false;
}
public function size()
{
return sizeof($this->content);
}
public function update_rule($index, $content)
{
// TODO: check this->supported
if ($this->content[$index]) {
$this->content[$index] = $content;
return $index;
}
return false;
}
/**
* Sets "global" variable
*
* @param string $name Variable name
* @param string $value Variable value
* @param array $mods Variable modifiers
*/
public function set_var($name, $value, $mods = array())
{
// Check if variable exists
for ($i=0, $len=count($this->vars); $i<$len; $i++) {
if ($this->vars[$i]['name'] == $name) {
break;
}
}
$var = array_merge($mods, array('name' => $name, 'value' => $value));
$this->vars[$i] = $var;
}
/**
* Unsets "global" variable
*
* @param string $name Variable name
*/
public function unset_var($name)
{
// Check if variable exists
foreach ($this->vars as $idx => $var) {
if ($var['name'] == $name) {
unset($this->vars[$idx]);
break;
}
}
}
/**
* Gets the value of "global" variable
*
* @param string $name Variable name
*
* @return string Variable value
*/
public function get_var($name)
{
// Check if variable exists
for ($i=0, $len=count($this->vars); $i<$len; $i++) {
if ($this->vars[$i]['name'] == $name) {
return $this->vars[$i]['name'];
}
}
}
/**
* Sets script header content
*
* @param string $text Header content
*/
public function set_prefix($text)
{
$this->prefix = $text;
}
/**
* Returns script as text
*/
public function as_text()
{
$output = '';
$exts = array();
$idx = 0;
if (!empty($this->vars)) {
if (in_array('variables', (array)$this->supported)) {
$has_vars = true;
array_push($exts, 'variables');
}
foreach ($this->vars as $var) {
if (empty($has_vars)) {
// 'variables' extension not supported, put vars in comments
$output .= sprintf("# %s %s\n", $var['name'], $var['value']);
}
else {
$output .= 'set ';
foreach (array_diff(array_keys($var), array('name', 'value')) as $opt) {
$output .= ":$opt ";
}
$output .= self::escape_string($var['name']) . ' ' . self::escape_string($var['value']) . ";\n";
}
}
}
// rules
foreach ($this->content as $rule) {
$extension = '';
$script = '';
$tests = array();
$i = 0;
// header
if (!empty($rule['name']) && strlen($rule['name'])) {
$script .= '# rule:[' . $rule['name'] . "]\n";
}
// constraints expressions
if (!empty($rule['tests'])) {
foreach ($rule['tests'] as $test) {
$tests[$i] = '';
switch ($test['test']) {
case 'size':
$tests[$i] .= ($test['not'] ? 'not ' : '');
$tests[$i] .= 'size :' . ($test['type']=='under' ? 'under ' : 'over ') . $test['arg'];
break;
case 'true':
$tests[$i] .= ($test['not'] ? 'false' : 'true');
break;
case 'exists':
$tests[$i] .= ($test['not'] ? 'not ' : '');
$tests[$i] .= 'exists ' . self::escape_string($test['arg']);
break;
case 'header':
$tests[$i] .= ($test['not'] ? 'not ' : '');
$tests[$i] .= 'header';
if (!empty($test['type'])) {
// relational operator + comparator
if (preg_match('/^(value|count)-([gteqnl]{2})/', $test['type'], $m)) {
array_push($exts, 'relational');
array_push($exts, 'comparator-i;ascii-numeric');
$tests[$i] .= ' :' . $m[1] . ' "' . $m[2] . '" :comparator "i;ascii-numeric"';
}
else {
$this->add_comparator($test, $tests[$i], $exts);
if ($test['type'] == 'regex') {
array_push($exts, 'regex');
}
$tests[$i] .= ' :' . $test['type'];
}
}
$tests[$i] .= ' ' . self::escape_string($test['arg1']);
$tests[$i] .= ' ' . self::escape_string($test['arg2']);
break;
case 'address':
case 'envelope':
if ($test['test'] == 'envelope') {
array_push($exts, 'envelope');
}
$tests[$i] .= ($test['not'] ? 'not ' : '');
$tests[$i] .= $test['test'];
if (!empty($test['part'])) {
$tests[$i] .= ' :' . $test['part'];
if ($test['part'] == 'user' || $test['part'] == 'detail') {
array_push($exts, 'subaddress');
}
}
$this->add_comparator($test, $tests[$i], $exts);
if (!empty($test['type'])) {
if ($test['type'] == 'regex') {
array_push($exts, 'regex');
}
$tests[$i] .= ' :' . $test['type'];
}
$tests[$i] .= ' ' . self::escape_string($test['arg1']);
$tests[$i] .= ' ' . self::escape_string($test['arg2']);
break;
case 'body':
array_push($exts, 'body');
$tests[$i] .= ($test['not'] ? 'not ' : '') . 'body';
$this->add_comparator($test, $tests[$i], $exts);
if (!empty($test['part'])) {
$tests[$i] .= ' :' . $test['part'];
if (!empty($test['content']) && $test['part'] == 'content') {
$tests[$i] .= ' ' . self::escape_string($test['content']);
}
}
if (!empty($test['type'])) {
if ($test['type'] == 'regex') {
array_push($exts, 'regex');
}
$tests[$i] .= ' :' . $test['type'];
}
$tests[$i] .= ' ' . self::escape_string($test['arg']);
break;
}
$i++;
}
}
// disabled rule: if false #....
if (!empty($tests)) {
$script .= 'if ' . ($rule['disabled'] ? 'false # ' : '');
if (count($tests) > 1) {
$tests_str = implode(', ', $tests);
}
else {
$tests_str = $tests[0];
}
if ($rule['join'] || count($tests) > 1) {
$script .= sprintf('%s (%s)', $rule['join'] ? 'allof' : 'anyof', $tests_str);
}
else {
$script .= $tests_str;
}
$script .= "\n{\n";
}
// action(s)
if (!empty($rule['actions'])) {
foreach ($rule['actions'] as $action) {
$action_script = '';
switch ($action['type']) {
case 'fileinto':
array_push($exts, 'fileinto');
$action_script .= 'fileinto ';
if ($action['copy']) {
$action_script .= ':copy ';
array_push($exts, 'copy');
}
$action_script .= self::escape_string($action['target']);
break;
case 'redirect':
$action_script .= 'redirect ';
if ($action['copy']) {
$action_script .= ':copy ';
array_push($exts, 'copy');
}
$action_script .= self::escape_string($action['target']);
break;
case 'reject':
case 'ereject':
array_push($exts, $action['type']);
$action_script .= $action['type'].' '
. self::escape_string($action['target']);
break;
case 'addflag':
case 'setflag':
case 'removeflag':
if (in_array('imap4flags', $this->supported))
array_push($exts, 'imap4flags');
else
array_push($exts, 'imapflags');
$action_script .= $action['type'].' '
. self::escape_string($action['target']);
break;
case 'keep':
case 'discard':
case 'stop':
$action_script .= $action['type'];
break;
case 'include':
array_push($exts, 'include');
$action_script .= 'include ';
foreach (array_diff(array_keys($action), array('target', 'type')) as $opt) {
$action_script .= ":$opt ";
}
$action_script .= self::escape_string($action['target']);
break;
case 'set':
array_push($exts, 'variables');
$action_script .= 'set ';
foreach (array_diff(array_keys($action), array('name', 'value', 'type')) as $opt) {
$action_script .= ":$opt ";
}
$action_script .= self::escape_string($action['name']) . ' ' . self::escape_string($action['value']);
break;
case 'vacation':
array_push($exts, 'vacation');
$action_script .= 'vacation';
if (!empty($action['days']))
$action_script .= " :days " . $action['days'];
if (!empty($action['addresses']))
$action_script .= " :addresses " . self::escape_string($action['addresses']);
if (!empty($action['subject']))
$action_script .= " :subject " . self::escape_string($action['subject']);
if (!empty($action['handle']))
$action_script .= " :handle " . self::escape_string($action['handle']);
if (!empty($action['from']))
$action_script .= " :from " . self::escape_string($action['from']);
if (!empty($action['mime']))
$action_script .= " :mime";
$action_script .= " " . self::escape_string($action['reason']);
break;
}
if ($action_script) {
$script .= !empty($tests) ? "\t" : '';
$script .= $action_script . ";\n";
}
}
}
if ($script) {
$output .= $script . (!empty($tests) ? "}\n" : '');
$idx++;
}
}
// requires
if (!empty($exts))
$output = 'require ["' . implode('","', array_unique($exts)) . "\"];\n" . $output;
if (!empty($this->prefix)) {
$output = $this->prefix . "\n\n" . $output;
}
return $output;
}
/**
* Returns script object
*
*/
public function as_array()
{
return $this->content;
}
/**
* Returns array of supported extensions
*
*/
public function get_extensions()
{
return array_values($this->supported);
}
/**
* Converts text script to rules array
*
* @param string Text script
*/
private function _parse_text($script)
{
$prefix = '';
$options = array();
while ($script) {
$script = trim($script);
$rule = array();
// Comments
while (!empty($script) && $script[0] == '#') {
$endl = strpos($script, "\n");
$line = $endl ? substr($script, 0, $endl) : $script;
// Roundcube format
if (preg_match('/^# rule:\[(.*)\]/', $line, $matches)) {
$rulename = $matches[1];
}
// KEP:14 variables
else if (preg_match('/^# (EDITOR|EDITOR_VERSION) (.+)$/', $line, $matches)) {
$this->set_var($matches[1], $matches[2]);
}
// Horde-Ingo format
else if (!empty($options['format']) && $options['format'] == 'INGO'
&& preg_match('/^# (.*)/', $line, $matches)
) {
$rulename = $matches[1];
}
else if (empty($options['prefix'])) {
$prefix .= $line . "\n";
}
$script = ltrim(substr($script, strlen($line) + 1));
}
// handle script header
if (empty($options['prefix'])) {
$options['prefix'] = true;
if ($prefix && strpos($prefix, 'horde.org/ingo')) {
$options['format'] = 'INGO';
}
}
// Control structures/blocks
if (preg_match('/^(if|else|elsif)/i', $script)) {
$rule = $this->_tokenize_rule($script);
if (strlen($rulename) && !empty($rule)) {
$rule['name'] = $rulename;
}
}
// Simple commands
else {
$rule = $this->_parse_actions($script, ';');
if (!empty($rule[0]) && is_array($rule)) {
// set "global" variables
if ($rule[0]['type'] == 'set') {
unset($rule[0]['type']);
$this->vars[] = $rule[0];
}
else {
$rule = array('actions' => $rule);
}
}
}
$rulename = '';
if (!empty($rule)) {
$this->content[] = $rule;
}
}
if (!empty($prefix)) {
$this->prefix = trim($prefix);
}
}
/**
* Convert text script fragment to rule object
*
* @param string Text rule
*
* @return array Rule data
*/
private function _tokenize_rule(&$content)
{
$cond = strtolower(self::tokenize($content, 1));
if ($cond != 'if' && $cond != 'elsif' && $cond != 'else') {
return null;
}
$disabled = false;
$join = false;
// disabled rule (false + comment): if false # .....
if (preg_match('/^\s*false\s+#/i', $content)) {
$content = preg_replace('/^\s*false\s+#\s*/i', '', $content);
$disabled = true;
}
while (strlen($content)) {
$tokens = self::tokenize($content, true);
$separator = array_pop($tokens);
if (!empty($tokens)) {
$token = array_shift($tokens);
}
else {
$token = $separator;
}
$token = strtolower($token);
if ($token == 'not') {
$not = true;
$token = strtolower(array_shift($tokens));
}
else {
$not = false;
}
switch ($token) {
case 'allof':
$join = true;
break;
case 'anyof':
break;
case 'size':
$size = array('test' => 'size', 'not' => $not);
for ($i=0, $len=count($tokens); $i<$len; $i++) {
if (!is_array($tokens[$i])
&& preg_match('/^:(under|over)$/i', $tokens[$i])
) {
$size['type'] = strtolower(substr($tokens[$i], 1));
}
else {
$size['arg'] = $tokens[$i];
}
}
$tests[] = $size;
break;
case 'header':
$header = array('test' => 'header', 'not' => $not, 'arg1' => '', 'arg2' => '');
for ($i=0, $len=count($tokens); $i<$len; $i++) {
if (!is_array($tokens[$i]) && preg_match('/^:comparator$/i', $tokens[$i])) {
$header['comparator'] = $tokens[++$i];
}
else if (!is_array($tokens[$i]) && preg_match('/^:(count|value)$/i', $tokens[$i])) {
$header['type'] = strtolower(substr($tokens[$i], 1)) . '-' . $tokens[++$i];
}
else if (!is_array($tokens[$i]) && preg_match('/^:(is|contains|matches|regex)$/i', $tokens[$i])) {
$header['type'] = strtolower(substr($tokens[$i], 1));
}
else {
$header['arg1'] = $header['arg2'];
$header['arg2'] = $tokens[$i];
}
}
$tests[] = $header;
break;
case 'address':
case 'envelope':
$header = array('test' => $token, 'not' => $not, 'arg1' => '', 'arg2' => '');
for ($i=0, $len=count($tokens); $i<$len; $i++) {
if (!is_array($tokens[$i]) && preg_match('/^:comparator$/i', $tokens[$i])) {
$header['comparator'] = $tokens[++$i];
}
else if (!is_array($tokens[$i]) && preg_match('/^:(is|contains|matches|regex)$/i', $tokens[$i])) {
$header['type'] = strtolower(substr($tokens[$i], 1));
}
else if (!is_array($tokens[$i]) && preg_match('/^:(localpart|domain|all|user|detail)$/i', $tokens[$i])) {
$header['part'] = strtolower(substr($tokens[$i], 1));
}
else {
$header['arg1'] = $header['arg2'];
$header['arg2'] = $tokens[$i];
}
}
$tests[] = $header;
break;
case 'body':
$header = array('test' => 'body', 'not' => $not, 'arg' => '');
for ($i=0, $len=count($tokens); $i<$len; $i++) {
if (!is_array($tokens[$i]) && preg_match('/^:comparator$/i', $tokens[$i])) {
$header['comparator'] = $tokens[++$i];
}
else if (!is_array($tokens[$i]) && preg_match('/^:(is|contains|matches|regex)$/i', $tokens[$i])) {
$header['type'] = strtolower(substr($tokens[$i], 1));
}
else if (!is_array($tokens[$i]) && preg_match('/^:(raw|content|text)$/i', $tokens[$i])) {
$header['part'] = strtolower(substr($tokens[$i], 1));
if ($header['part'] == 'content') {
$header['content'] = $tokens[++$i];
}
}
else {
$header['arg'] = $tokens[$i];
}
}
$tests[] = $header;
break;
case 'exists':
$tests[] = array('test' => 'exists', 'not' => $not,
'arg' => array_pop($tokens));
break;
case 'true':
$tests[] = array('test' => 'true', 'not' => $not);
break;
case 'false':
$tests[] = array('test' => 'true', 'not' => !$not);
break;
}
// goto actions...
if ($separator == '{') {
break;
}
}
// ...and actions block
$actions = $this->_parse_actions($content);
if ($tests && $actions) {
$result = array(
'type' => $cond,
'tests' => $tests,
'actions' => $actions,
'join' => $join,
'disabled' => $disabled,
);
}
return $result;
}
/**
* Parse body of actions section
*
* @param string $content Text body
* @param string $end End of text separator
*
* @return array Array of parsed action type/target pairs
*/
private function _parse_actions(&$content, $end = '}')
{
$result = null;
while (strlen($content)) {
$tokens = self::tokenize($content, true);
$separator = array_pop($tokens);
if (!empty($tokens)) {
$token = array_shift($tokens);
}
else {
$token = $separator;
}
switch ($token) {
case 'discard':
case 'keep':
case 'stop':
$result[] = array('type' => $token);
break;
case 'fileinto':
case 'redirect':
$copy = false;
$target = '';
for ($i=0, $len=count($tokens); $i<$len; $i++) {
if (strtolower($tokens[$i]) == ':copy') {
$copy = true;
}
else {
$target = $tokens[$i];
}
}
$result[] = array('type' => $token, 'copy' => $copy,
'target' => $target);
break;
case 'reject':
case 'ereject':
$result[] = array('type' => $token, 'target' => array_pop($tokens));
break;
case 'vacation':
$vacation = array('type' => 'vacation', 'reason' => array_pop($tokens));
for ($i=0, $len=count($tokens); $i<$len; $i++) {
$tok = strtolower($tokens[$i]);
if ($tok == ':days') {
$vacation['days'] = $tokens[++$i];
}
else if ($tok == ':subject') {
$vacation['subject'] = $tokens[++$i];
}
else if ($tok == ':addresses') {
$vacation['addresses'] = $tokens[++$i];
}
else if ($tok == ':handle') {
$vacation['handle'] = $tokens[++$i];
}
else if ($tok == ':from') {
$vacation['from'] = $tokens[++$i];
}
else if ($tok == ':mime') {
$vacation['mime'] = true;
}
}
$result[] = $vacation;
break;
case 'setflag':
case 'addflag':
case 'removeflag':
$result[] = array('type' => $token,
// Flags list: last token (skip optional variable)
'target' => $tokens[count($tokens)-1]
);
break;
case 'include':
$include = array('type' => 'include', 'target' => array_pop($tokens));
// Parameters: :once, :optional, :global, :personal
for ($i=0, $len=count($tokens); $i<$len; $i++) {
$tok = strtolower($tokens[$i]);
if ($tok[0] == ':') {
$include[substr($tok, 1)] = true;
}
}
$result[] = $include;
break;
case 'set':
$set = array('type' => 'set', 'value' => array_pop($tokens), 'name' => array_pop($tokens));
// Parameters: :lower :upper :lowerfirst :upperfirst :quotewildcard :length
for ($i=0, $len=count($tokens); $i<$len; $i++) {
$tok = strtolower($tokens[$i]);
if ($tok[0] == ':') {
$set[substr($tok, 1)] = true;
}
}
$result[] = $set;
break;
case 'require':
// skip, will be build according to used commands
// $result[] = array('type' => 'require', 'target' => $tokens);
break;
}
if ($separator == $end)
break;
}
return $result;
}
/**
*
*/
private function add_comparator($test, &$out, &$exts)
{
if (empty($test['comparator'])) {
return;
}
if ($test['comparator'] == 'i;ascii-numeric') {
array_push($exts, 'relational');
array_push($exts, 'comparator-i;ascii-numeric');
}
else if (!in_array($test['comparator'], array('i;octet', 'i;ascii-casemap'))) {
array_push($exts, 'comparator-' . $test['comparator']);
}
// skip default comparator
if ($test['comparator'] != 'i;ascii-casemap') {
$out .= ' :comparator ' . self::escape_string($test['comparator']);
}
}
/**
* Escape special chars into quoted string value or multi-line string
* or list of strings
*
* @param string $str Text or array (list) of strings
*
* @return string Result text
*/
static function escape_string($str)
{
if (is_array($str) && count($str) > 1) {
foreach($str as $idx => $val)
$str[$idx] = self::escape_string($val);
return '[' . implode(',', $str) . ']';
}
else if (is_array($str)) {
$str = array_pop($str);
}
// multi-line string
if (preg_match('/[\r\n\0]/', $str) || strlen($str) > 1024) {
return sprintf("text:\n%s\n.\n", self::escape_multiline_string($str));
}
// quoted-string
else {
return '"' . addcslashes($str, '\\"') . '"';
}
}
/**
* Escape special chars in multi-line string value
*
* @param string $str Text
*
* @return string Text
*/
static function escape_multiline_string($str)
{
$str = preg_split('/(\r?\n)/', $str, -1, PREG_SPLIT_DELIM_CAPTURE);
foreach ($str as $idx => $line) {
// dot-stuffing
if (isset($line[0]) && $line[0] == '.') {
$str[$idx] = '.' . $line;
}
}
return implode($str);
}
/**
* Splits script into string tokens
*
* @param string &$str The script
* @param mixed $num Number of tokens to return, 0 for all
* or True for all tokens until separator is found.
* Separator will be returned as last token.
* @param int $in_list Enable to call recursively inside a list
*
* @return mixed Tokens array or string if $num=1
*/
static function tokenize(&$str, $num=0, $in_list=false)
{
$result = array();
// remove spaces from the beginning of the string
while (($str = ltrim($str)) !== ''
&& (!$num || $num === true || count($result) < $num)
) {
switch ($str[0]) {
// Quoted string
case '"':
$len = strlen($str);
for ($pos=1; $pos<$len; $pos++) {
if ($str[$pos] == '"') {
break;
}
if ($str[$pos] == "\\") {
if ($str[$pos + 1] == '"' || $str[$pos + 1] == "\\") {
$pos++;
}
}
}
if ($str[$pos] != '"') {
// error
}
// we need to strip slashes for a quoted string
$result[] = stripslashes(substr($str, 1, $pos - 1));
$str = substr($str, $pos + 1);
break;
// Parenthesized list
case '[':
$str = substr($str, 1);
$result[] = self::tokenize($str, 0, true);
break;
case ']':
$str = substr($str, 1);
return $result;
break;
// list/test separator
case ',':
// command separator
case ';':
// block/tests-list
case '(':
case ')':
case '{':
case '}':
$sep = $str[0];
$str = substr($str, 1);
if ($num === true) {
$result[] = $sep;
break 2;
}
break;
// bracket-comment
case '/':
if ($str[1] == '*') {
if ($end_pos = strpos($str, '*/')) {
$str = substr($str, $end_pos + 2);
}
else {
// error
$str = '';
}
}
break;
// hash-comment
case '#':
if ($lf_pos = strpos($str, "\n")) {
$str = substr($str, $lf_pos);
break;
}
else {
$str = '';
}
// String atom
default:
// empty or one character
if ($str === '' || $str === null) {
break 2;
}
if (strlen($str) < 2) {
$result[] = $str;
$str = '';
break;
}
// tag/identifier/number
if (preg_match('/^([a-z0-9:_]+)/i', $str, $m)) {
$str = substr($str, strlen($m[1]));
if ($m[1] != 'text:') {
$result[] = $m[1];
}
// multiline string
else {
// possible hash-comment after "text:"
if (preg_match('/^( |\t)*(#[^\n]+)?\n/', $str, $m)) {
$str = substr($str, strlen($m[0]));
}
// get text until alone dot in a line
if (preg_match('/^(.*)\r?\n\.\r?\n/sU', $str, $m)) {
$text = $m[1];
// remove dot-stuffing
$text = str_replace("\n..", "\n.", $text);
$str = substr($str, strlen($m[0]));
}
else {
$text = '';
}
$result[] = $text;
}
}
// fallback, skip one character as infinite loop prevention
else {
$str = substr($str, 1);
}
break;
}
}
return $num === 1 ? (isset($result[0]) ? $result[0] : null) : $result;
}
}