mailcow/data/web/inc/lib/sieve/SieveScanner.php

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PHP
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<?php namespace Sieve;
include_once('SieveToken.php');
class SieveScanner
{
public function __construct(&$script)
{
if ($script === null)
return;
$this->tokenize($script);
}
public function setPassthroughFunc($callback)
{
if ($callback == null || is_callable($callback))
$this->ptFn_ = $callback;
}
public function tokenize(&$script)
{
$pos = 0;
$line = 1;
$scriptLength = mb_strlen($script);
$unprocessedScript = $script;
//create one regex to find the right match
//avoids looping over all possible tokens: increases performance
$nameToType = [];
$regex = [];
// chr(65) == 'A'
$i = 65;
foreach ($this->tokenMatch_ as $type => $subregex) {
$nameToType[chr($i)] = $type;
$regex[] = "(?P<". chr($i) . ">^$subregex)";
$i++;
}
$regex = '/' . join('|', $regex) . '/';
while ($pos < $scriptLength)
{
if (preg_match($regex, $unprocessedScript, $match)) {
// only keep the group that match and we only want matches with group names
// we can use the group name to find the token type using nameToType
$filterMatch = array_filter(array_filter($match), 'is_string', ARRAY_FILTER_USE_KEY);
// the first element in filterMatch will contain the matched group and the key will be the name
$type = $nameToType[key($filterMatch)];
$currentMatch = current($filterMatch);
//create the token
$token = new SieveToken($type, $currentMatch, $line);
$this->tokens_[] = $token;
if ($type == SieveToken::Unknown)
return;
// just remove the part that we parsed: don't extract the new substring using script length
// as mb_strlen is \theta(pos) (it's linear in the position)
$matchLength = mb_strlen($currentMatch);
$unprocessedScript = mb_substr($unprocessedScript, $matchLength);
$pos += $matchLength;
$line += mb_substr_count($currentMatch, "\n");
} else {
$this->tokens_[] = new SieveToken(SieveToken::Unknown, '', $line);
return;
}
}
$this->tokens_[] = new SieveToken(SieveToken::ScriptEnd, '', $line);
}
public function nextTokenIs($type)
{
return $this->peekNextToken()->is($type);
}
public function peekNextToken()
{
$offset = 0;
do {
$next = $this->tokens_[$this->tokenPos_ + $offset++];
} while ($next->is(SieveToken::Comment|SieveToken::Whitespace));
return $next;
}
public function nextToken()
{
$token = $this->tokens_[$this->tokenPos_++];
while ($token->is(SieveToken::Comment|SieveToken::Whitespace))
{
if ($this->ptFn_ != null)
call_user_func($this->ptFn_, $token);
$token = $this->tokens_[$this->tokenPos_++];
}
return $token;
}
protected $ptFn_ = null;
protected $tokenPos_ = 0;
protected $tokens_ = array();
protected $tokenMatch_ = array (
SieveToken::LeftBracket => '\[',
SieveToken::RightBracket => '\]',
SieveToken::BlockStart => '\{',
SieveToken::BlockEnd => '\}',
SieveToken::LeftParenthesis => '\(',
SieveToken::RightParenthesis => '\)',
SieveToken::Comma => ',',
SieveToken::Semicolon => ';',
SieveToken::Whitespace => '[ \r\n\t]+',
SieveToken::Tag => ':[[:alpha:]_][[:alnum:]_]*(?=\b)',
/*
" # match a quotation mark
( # start matching parts that include an escaped quotation mark
([^"]*[^"\\\\]) # match a string without quotation marks and not ending with a backlash
? # this also includes the empty string
(\\\\\\\\)* # match any groups of even number of backslashes
# (thus the character after these groups are not escaped)
\\\\" # match an escaped quotation mark
)* # accept any number of strings that end with an escaped quotation mark
[^"]* # accept any trailing part that does not contain any quotation marks
" # end of the quoted string
*/
SieveToken::QuotedString => '"(([^"]*[^"\\\\])?(\\\\\\\\)*\\\\")*[^"]*"',
SieveToken::Number => '[[:digit:]]+(?:[KMG])?(?=\b)',
SieveToken::Comment => '(?:\/\*(?:[^\*]|\*(?=[^\/]))*\*\/|#[^\r\n]*\r?(\n|$))',
SieveToken::MultilineString => 'text:[ \t]*(?:#[^\r\n]*)?\r?\n(\.[^\r\n]+\r?\n|[^\.][^\r\n]*\r?\n)*\.\r?(\n|$)',
SieveToken::Identifier => '[[:alpha:]_][[:alnum:]_]*(?=\b)',
SieveToken::Unknown => '[^ \r\n\t]+'
);
}