Parser::ptrHandler() - Code Metrics - Inspection of "Issue 75 (#76)" - Badcow/DNS - Measure and Improve Code Quality continuously with Scrutinizer

Completed

Push — master ( 1a3f9c...9e9273 )

by Sam

created 2020-10-05 05:32 UTC

Parser::ptrHandler() A

↳ Parent: Project

Complexity

Conditions	4
Paths	3

Size

Total Lines	13
Code Lines	7

Duplication

Lines	0
Ratio	0 %

Code Coverage

Tests	5
CRAP Score	4.8437

Importance

Changes

Metric	Value
cc	4
eloc	7
c	0
b	0
f	0
nc	3
nop	1
dl	0
loc	13
ccs	5
cts	8
cp	0.625
crap	4.8437
rs	10

<?php

declare(strict_types=1);

/*
 * This file is part of Badcow DNS Library.
 *
 * (c) Samuel Williams <[email protected]>
 *
 * For the full copyright and license information, please view the LICENSE
 * file that was distributed with this source code.
 */

namespace Badcow\DNS\Parser;

use Badcow\DNS\Classes;
use Badcow\DNS\Rdata\Factory;
use Badcow\DNS\Rdata\RdataInterface;
use Badcow\DNS\Rdata\Types;
use Badcow\DNS\ResourceRecord;
use Badcow\DNS\Zone;
use Exception;

class Parser
{
    /**
     * @var Zone
     */
    private $zone;

    /**
     * Array of methods that take an ArrayIterator and return an Rdata object. The array key is the Rdata type.
     *
     * @var callable[]
     */
    private $rdataHandlers = [];

    /**
     * @var ResourceRecord
     */
    private $currentResourceRecord;

    /**
     * @var string
     */
    private $lastStatedDomain;

    /**
     * @var int
     */
    private $lastStatedTtl;

    /**
     * @var string
     */
    private $lastStatedClass;

    /**
     * Parser constructor.
     */
    public function __construct(array $rdataHandlers = [])
    {
        $this->rdataHandlers = $rdataHandlers;
    }

    /**
     * @throws ParseException
     */
    public static function parse(string $name, string $zone, int $commentOptions = Comments::NONE): Zone
    {
        return (new self())->makeZone($name, $zone, $commentOptions);
    }

    /**
     * @throws ParseException
     */
    public function makeZone(string $name, string $string, int $commentOptions = Comments::NONE): Zone
    {
        $this->zone = new Zone($name);
        $this->lastStatedDomain = $name;
        $normalisedZone = Normaliser::normalise($string, $commentOptions);

        foreach (explode(Tokens::LINE_FEED, $normalisedZone) as $line) {
            $this->processLine($line);
        }

        return $this->zone;
    }

    /**
     * @throws ParseException
     */
    private function processLine(string $line): void
    {
        list($entry, $comment) = $this->extractComment($line);

        $this->currentResourceRecord = new ResourceRecord();
        $this->currentResourceRecord->setComment($comment);

        if ('' === $entry) {
            $this->zone->addResourceRecord($this->currentResourceRecord);

            return;
        }

        $iterator = new ResourceRecordIterator($entry);

        if ($this->isControlEntry($iterator)) {
            $this->processControlEntry($iterator);

            return;
        }

        $this->processEntry($iterator);
        $this->zone->addResourceRecord($this->currentResourceRecord);
    }

    /**
     * @throws ParseException
     */
    private function processEntry(ResourceRecordIterator $iterator): void
    {
        if ($this->isTTL($iterator)) {
            $this->currentResourceRecord->setTtl(TimeFormat::toSeconds($iterator->current()));
            $iterator->next();
            $this->processEntry($iterator);

            return;
        }

        if ($this->isClass($iterator)) {
            $this->currentResourceRecord->setClass(strtoupper($iterator->current()));
            $iterator->next();
            $this->processEntry($iterator);

            return;
        }

        if ($this->isResourceName($iterator) && null === $this->currentResourceRecord->getName()) {

            $this->currentResourceRecord->setName($iterator->current());
            $iterator->next();
            $this->processEntry($iterator);

            return;
        }

        if ($this->isType($iterator)) {
            $this->currentResourceRecord->setRdata($this->extractRdata($iterator));
            $this->populateWithLastStated();

            return;
        }

        throw new ParseException(sprintf('Could not parse entry "%s".', implode(' ', $iterator->getArrayCopy())));
    }

    /**
     * If no domain-name, TTL, or class is set on the record, populate object with last stated value.
     *
     * @see https://www.ietf.org/rfc/rfc1035 Section 5.1
     */
    private function populateWithLastStated(): void
    {
        if (empty($this->currentResourceRecord->getName())) {
            $this->currentResourceRecord->setName($this->lastStatedDomain);
        } else {
            $this->lastStatedDomain = $this->currentResourceRecord->getName();
        }

        if (null === $this->currentResourceRecord->getTtl()) {
            $this->currentResourceRecord->setTtl($this->lastStatedTtl ?? $this->zone->getDefaultTTl());
        } else {
            $this->lastStatedTtl = $this->currentResourceRecord->getTtl();
        }

        if (null === $this->currentResourceRecord->getClass()) {
            $this->currentResourceRecord->setClass($this->lastStatedClass);
        } else {
            $this->lastStatedClass = $this->currentResourceRecord->getClass();
        }
    }

    /**
     * Processes control entries at the top of a BIND record, i.e. $ORIGIN, $TTL, $INCLUDE, etc.
     */
    private function processControlEntry(ResourceRecordIterator $iterator): void
    {
        if ('$TTL' === strtoupper($iterator->current())) {
            $iterator->next();
            $this->zone->setDefaultTtl(TimeFormat::toSeconds($iterator->current()));
        }

        if ('$ORIGIN' === strtoupper($iterator->current())) {
            $iterator->next();
            $this->zone->setName((string) $iterator->current());
        }
    }

    /**
     * Determine if iterant is a resource name.
     */
    private function isResourceName(ResourceRecordIterator $iterator): bool
    {
        // Look ahead and determine if the next token is a TTL, Class, or valid Type.
        $iterator->next();

        if (!$iterator->valid()) {
            return false;
        }

        $isName = $this->isTTL($iterator) ||
            $this->isClass($iterator, 'DOMAIN') ||
            $this->isType($iterator);
        $iterator->prev();

        if (!$isName) {
            return false;
        }

        if (0 === $iterator->key()) {
            return true;
        }

        return false;
    }

    /**
     * Determine if iterant is a class.
     *
     * @param string|null $origin the previously assumed resource record parameter, either 'TTL' or NULL
     */
    private function isClass(ResourceRecordIterator $iterator, $origin = null): bool
    {
        if (!Classes::isValid($iterator->current())) {
            return false;
        }

        $iterator->next();
        if ('TTL' === $origin) {
            $isClass = $this->isType($iterator);
        } else {
            $isClass = $this->isTTL($iterator, 'CLASS') || $this->isType($iterator);
        }
        $iterator->prev();

        return $isClass;
    }

    /**
     * Determine if current iterant is an Rdata type string.
     */
    private function isType(ResourceRecordIterator $iterator): bool
    {
        return Types::isValid(strtoupper($iterator->current())) || array_key_exists($iterator->current(), $this->rdataHandlers);
    }

    /**
     * Determine if iterant is a control entry such as $TTL, $ORIGIN, $INCLUDE, etcetera.
     */
    private function isControlEntry(ResourceRecordIterator $iterator): bool
    {
        return 1 === preg_match('/^\$[A-Z0-9]+/i', $iterator->current());
    }

    /**
     * Determine if the iterant is a TTL (i.e. it is an integer after domain-name).
     *
     * @param string $origin the previously assumed resource record parameter, either 'CLASS' or NULL
     */
    private function isTTL(ResourceRecordIterator $iterator, $origin = null): bool
    {
        if (!TimeFormat::isTimeFormat($iterator->current())) {
            return false;
        }

        if ($iterator->key() < 1) {
            return false;
        }

        $iterator->next();
        if ('CLASS' === $origin) {
            $isTtl = $this->isType($iterator);
        } else {
            $isTtl = $this->isClass($iterator, 'TTL') || $this->isType($iterator);
        }
        $iterator->prev();

        return $isTtl;
    }

    /**
     * Split a DNS zone line into a resource record and a comment.
     *
     * @return array [$entry, $comment]
     */
    private function extractComment(string $rr): array
    {
        $string = new StringIterator($rr);
        $entry = '';
        $comment = null;

        while ($string->valid()) {
            //If a semicolon is within double quotes, it will not be treated as the beginning of a comment.
            $entry .= $this->extractDoubleQuotedText($string);

            if ($string->is(Tokens::SEMICOLON)) {
                $string->next();
                $comment = $string->getRemainingAsString();

                break;
            }

            $entry .= $string->current();
            $string->next();
        }

        return [$entry, $comment];
    }

    /**
     * Extract text within double quotation context.
     */
    private function extractDoubleQuotedText(StringIterator $string): string
    {
        if ($string->isNot(Tokens::DOUBLE_QUOTES)) {
            return '';
        }

        $entry = $string->current();
        $string->next();

        while ($string->isNot(Tokens::DOUBLE_QUOTES)) {
            //If the current char is a backslash, treat the next char as being escaped.
            if ($string->is(Tokens::BACKSLASH)) {
                $entry .= $string->current();
                $string->next();
            }
            $entry .= $string->current();
            $string->next();
        }

        return $entry;
    }

    /**
     * @throws ParseException
     */
    private function extractRdata(ResourceRecordIterator $iterator): RdataInterface
    {
        $type = strtoupper($iterator->current());
        $iterator->next();

        if (array_key_exists($type, $this->rdataHandlers)) {
            return call_user_func($this->rdataHandlers[$type], $iterator);
        }

        try {
            return Factory::textToRdataType($type, $iterator->getRemainingAsString());
        } catch (Exception $exception) {
            throw new ParseException(sprintf('Could not extract Rdata from resource record "%s".', (string) $iterator), null, $exception);
        }
    }
}


1		<?php
2
3		declare(strict_types=1);
4
5		/*
6		* This file is part of Badcow DNS Library.
7		*
8		* (c) Samuel Williams <[email protected]>
9		*
10		* For the full copyright and license information, please view the LICENSE
11		* file that was distributed with this source code.
12		*/
13
14		namespace Badcow\DNS\Parser;
15
16		use Badcow\DNS\Classes;
17		use Badcow\DNS\Rdata\Factory;
18		use Badcow\DNS\Rdata\RdataInterface;
19		use Badcow\DNS\Rdata\Types;
20		use Badcow\DNS\ResourceRecord;
21		use Badcow\DNS\Zone;
22		use Exception;
23
24		class Parser
25		{
26		/**
27		* @var Zone
28		*/
29		private $zone;
30
31		/**
32		* Array of methods that take an ArrayIterator and return an Rdata object. The array key is the Rdata type.
33		*
34		* @var callable[]
35		*/
36		private $rdataHandlers = [];
37
38		/**
39		* @var ResourceRecord
40		*/
41		private $currentResourceRecord;
42
43		/**
44		* @var string
45		*/
46		private $lastStatedDomain;
47
48		/**
49		* @var int
50		*/
51		private $lastStatedTtl;
52
53		/**
54		* @var string
55		*/
56		private $lastStatedClass;
57
58		/**
59		* Parser constructor.
60		*/
61	27	public function __construct(array $rdataHandlers = [])
62		{
63	27	$this->rdataHandlers = $rdataHandlers;
64	27	}
65
66		/**
67		* @throws ParseException
68		*/
69	26	public static function parse(string $name, string $zone, int $commentOptions = Comments::NONE): Zone
70		{
71	26	return (new self())->makeZone($name, $zone, $commentOptions);
72		}
73
74		/**
75		* @throws ParseException
76		*/
77	27	public function makeZone(string $name, string $string, int $commentOptions = Comments::NONE): Zone
78		{
79	27	$this->zone = new Zone($name);
80	27	$this->lastStatedDomain = $name;
81	27	$normalisedZone = Normaliser::normalise($string, $commentOptions);
82
83	27	foreach (explode(Tokens::LINE_FEED, $normalisedZone) as $line) {
84	27	$this->processLine($line);
85		}
86
87	24	return $this->zone;
88		}
89
90		/**
91		* @throws ParseException
92		*/
93	27	private function processLine(string $line): void
94		{
95	27	list($entry, $comment) = $this->extractComment($line);
96
97	27	$this->currentResourceRecord = new ResourceRecord();
98	27	$this->currentResourceRecord->setComment($comment);
99
100	27	if ('' === $entry) {
101	2	$this->zone->addResourceRecord($this->currentResourceRecord);
102
103	2	return;
104		}
105
106	27	$iterator = new ResourceRecordIterator($entry);
107
108	27	if ($this->isControlEntry($iterator)) {
109	12	$this->processControlEntry($iterator);
110
111	12	return;
112		}
113
114	27	$this->processEntry($iterator);
115	24	$this->zone->addResourceRecord($this->currentResourceRecord);
116	24	}
117
118		/**
119		* @throws ParseException
120		*/
121	27	private function processEntry(ResourceRecordIterator $iterator): void
122		{
123	27	if ($this->isTTL($iterator)) {
124	15	$this->currentResourceRecord->setTtl(TimeFormat::toSeconds($iterator->current()));
125	15	$iterator->next();
126	15	$this->processEntry($iterator);
127
128	13	return;
129		}
130
131	27	if ($this->isClass($iterator)) {
132	24	$this->currentResourceRecord->setClass(strtoupper($iterator->current()));
133	24	$iterator->next();
134	24	$this->processEntry($iterator);
135
136	22	return;
137		}
138
139	27	if ($this->isResourceName($iterator) && null === $this->currentResourceRecord->getName()) {
		0 ignored issues – show introduced 2019-11-28 09:22 UTC by Report Bug Copy Issue Report The condition `null === $this->currentResourceRecord->getName()` is always `false`. Loading history...
140	26	$this->currentResourceRecord->setName($iterator->current());
141	26	$iterator->next();
142	26	$this->processEntry($iterator);
143
144	24	return;
145		}
146
147	27	if ($this->isType($iterator)) {
148	26	$this->currentResourceRecord->setRdata($this->extractRdata($iterator));
149	24	$this->populateWithLastStated();
150
151	24	return;
152		}
153
154	1	throw new ParseException(sprintf('Could not parse entry "%s".', implode(' ', $iterator->getArrayCopy())));
155		}
156
157		/**
158		* If no domain-name, TTL, or class is set on the record, populate object with last stated value.
159		*
160		* @see https://www.ietf.org/rfc/rfc1035 Section 5.1
161		*/
162	24	private function populateWithLastStated(): void
163		{
164	24	if (empty($this->currentResourceRecord->getName())) {
165	4	$this->currentResourceRecord->setName($this->lastStatedDomain);
166		} else {
167	23	$this->lastStatedDomain = $this->currentResourceRecord->getName();
168		}
169
170	24	if (null === $this->currentResourceRecord->getTtl()) {
171	14	$this->currentResourceRecord->setTtl($this->lastStatedTtl ?? $this->zone->getDefaultTTl());
172		} else {
173	13	$this->lastStatedTtl = $this->currentResourceRecord->getTtl();
174		}
175
176	24	if (null === $this->currentResourceRecord->getClass()) {
177		$this->currentResourceRecord->setClass($this->lastStatedClass);
178		} else {
179	24	$this->lastStatedClass = $this->currentResourceRecord->getClass();
180		}
181	24	}
182
183		/**
184		* Processes control entries at the top of a BIND record, i.e. $ORIGIN, $TTL, $INCLUDE, etc.
185		*/
186	12	private function processControlEntry(ResourceRecordIterator $iterator): void
187		{
188	12	if ('$TTL' === strtoupper($iterator->current())) {
189	10	$iterator->next();
190	10	$this->zone->setDefaultTtl(TimeFormat::toSeconds($iterator->current()));
191		}
192
193	12	if ('$ORIGIN' === strtoupper($iterator->current())) {
194	11	$iterator->next();
195	11	$this->zone->setName((string) $iterator->current());
196		}
197	12	}
198
199		/**
200		* Determine if iterant is a resource name.
201		*/
202	27	private function isResourceName(ResourceRecordIterator $iterator): bool
203		{
204		// Look ahead and determine if the next token is a TTL, Class, or valid Type.
205	27	$iterator->next();
206
207	27	if (!$iterator->valid()) {
208		return false;
209		}
210
211	27	$isName = $this->isTTL($iterator) \|\|
212	27	$this->isClass($iterator, 'DOMAIN') \|\|
213	27	$this->isType($iterator);
214	27	$iterator->prev();
215
216	27	if (!$isName) {
217	25	return false;
218		}
219
220	26	if (0 === $iterator->key()) {
221	26	return true;
222		}
223
224	4	return false;
225		}
226
227		/**
228		* Determine if iterant is a class.
229		*
230		* @param string\|null $origin the previously assumed resource record parameter, either 'TTL' or NULL
231		*/
232	27	private function isClass(ResourceRecordIterator $iterator, $origin = null): bool
233		{
234	27	if (!Classes::isValid($iterator->current())) {
235	27	return false;
236		}
237
238	25	$iterator->next();
239	25	if ('TTL' === $origin) {
240	12	$isClass = $this->isType($iterator);
241		} else {
242	24	$isClass = $this->isTTL($iterator, 'CLASS') \|\| $this->isType($iterator);
243		}
244	25	$iterator->prev();
245
246	25	return $isClass;
247		}
248
249		/**
250		* Determine if current iterant is an Rdata type string.
251		*/
252	27	private function isType(ResourceRecordIterator $iterator): bool
253		{
254	27	return Types::isValid(strtoupper($iterator->current())) \|\| array_key_exists($iterator->current(), $this->rdataHandlers);
255		}
256
257		/**
258		* Determine if iterant is a control entry such as $TTL, $ORIGIN, $INCLUDE, etcetera.
259		*/
260	27	private function isControlEntry(ResourceRecordIterator $iterator): bool
261		{
262	27	return 1 === preg_match('/^\$[A-Z0-9]+/i', $iterator->current());
263		}
264
265		/**
266		* Determine if the iterant is a TTL (i.e. it is an integer after domain-name).
267		*
268		* @param string $origin the previously assumed resource record parameter, either 'CLASS' or NULL
269		*/
270	27	private function isTTL(ResourceRecordIterator $iterator, $origin = null): bool
271		{
272	27	if (!TimeFormat::isTimeFormat($iterator->current())) {
273	27	return false;
274		}
275
276	25	if ($iterator->key() < 1) {
277	6	return false;
278		}
279
280	24	$iterator->next();
281	24	if ('CLASS' === $origin) {
282	5	$isTtl = $this->isType($iterator);
283		} else {
284	24	$isTtl = $this->isClass($iterator, 'TTL') \|\| $this->isType($iterator);
285		}
286	24	$iterator->prev();
287
288	24	return $isTtl;
289		}
290
291		/**
292		* Split a DNS zone line into a resource record and a comment.
293		*
294		* @return array [$entry, $comment]
295		*/
296	27	private function extractComment(string $rr): array
297		{
298	27	$string = new StringIterator($rr);
299	27	$entry = '';
300	27	$comment = null;
301
302	27	while ($string->valid()) {
303		//If a semicolon is within double quotes, it will not be treated as the beginning of a comment.
304	27	$entry .= $this->extractDoubleQuotedText($string);
305
306	27	if ($string->is(Tokens::SEMICOLON)) {
307	4	$string->next();
308	4	$comment = $string->getRemainingAsString();
309
310	4	break;
311		}
312
313	27	$entry .= $string->current();
314	27	$string->next();
315		}
316
317	27	return [$entry, $comment];
318		}
319
320		/**
321		* Extract text within double quotation context.
322		*/
323	27	private function extractDoubleQuotedText(StringIterator $string): string
324		{
325	27	if ($string->isNot(Tokens::DOUBLE_QUOTES)) {
326	27	return '';
327		}
328
329	12	$entry = $string->current();
330	12	$string->next();
331
332	12	while ($string->isNot(Tokens::DOUBLE_QUOTES)) {
333		//If the current char is a backslash, treat the next char as being escaped.
334	12	if ($string->is(Tokens::BACKSLASH)) {
335	6	$entry .= $string->current();
336	6	$string->next();
337		}
338	12	$entry .= $string->current();
339	12	$string->next();
340		}
341
342	12	return $entry;
343		}
344
345		/**
346		* @throws ParseException
347		*/
348	26	private function extractRdata(ResourceRecordIterator $iterator): RdataInterface
349		{
350	26	$type = strtoupper($iterator->current());
351	26	$iterator->next();
352
353	26	if (array_key_exists($type, $this->rdataHandlers)) {
354	1	return call_user_func($this->rdataHandlers[$type], $iterator);
355		}
356
357		try {
358	25	return Factory::textToRdataType($type, $iterator->getRemainingAsString());
359	2	} catch (Exception $exception) {
360	2	throw new ParseException(sprintf('Could not extract Rdata from resource record "%s".', (string) $iterator), null, $exception);
361		}
362		}
363		}
364

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Parser::ptrHandler() A

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