This file is indexed.

/usr/share/php/Predis/Transaction/MultiExecContext.php is in libphp-predis 0.8.3-1.

This file is owned by root:root, with mode 0o644.

The actual contents of the file can be viewed below.

  1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
<?php

/*
 * This file is part of the Predis package.
 *
 * (c) Daniele Alessandri <suppakilla@gmail.com>
 *
 * For the full copyright and license information, please view the LICENSE
 * file that was distributed with this source code.
 */

namespace Predis\Transaction;

use SplQueue;
use Predis\BasicClientInterface;
use Predis\ClientException;
use Predis\ClientInterface;
use Predis\CommunicationException;
use Predis\ExecutableContextInterface;
use Predis\NotSupportedException;
use Predis\ResponseErrorInterface;
use Predis\ResponseQueued;
use Predis\ServerException;
use Predis\Command\CommandInterface;
use Predis\Connection\AggregatedConnectionInterface;
use Predis\Protocol\ProtocolException;

/**
 * Client-side abstraction of a Redis transaction based on MULTI / EXEC.
 *
 * @author Daniele Alessandri <suppakilla@gmail.com>
 */
class MultiExecContext implements BasicClientInterface, ExecutableContextInterface
{
    const STATE_RESET       = 0;    // 0b00000
    const STATE_INITIALIZED = 1;    // 0b00001
    const STATE_INSIDEBLOCK = 2;    // 0b00010
    const STATE_DISCARDED   = 4;    // 0b00100
    const STATE_CAS         = 8;    // 0b01000
    const STATE_WATCH       = 16;   // 0b10000

    private $state;
    private $canWatch;

    protected $client;
    protected $options;
    protected $commands;

    /**
     * @param ClientInterface Client instance used by the context.
     * @param array Options for the context initialization.
     */
    public function __construct(ClientInterface $client, Array $options = null)
    {
        $this->checkCapabilities($client);
        $this->options = $options ?: array();
        $this->client = $client;
        $this->reset();
    }

    /**
     * Sets the internal state flags.
     *
     * @param int $flags Set of flags
     */
    protected function setState($flags)
    {
        $this->state = $flags;
    }

    /**
     * Gets the internal state flags.
     *
     * @return int
     */
    protected function getState()
    {
        return $this->state;
    }

    /**
     * Sets one or more flags.
     *
     * @param int $flags Set of flags
     */
    protected function flagState($flags)
    {
        $this->state |= $flags;
    }

    /**
     * Resets one or more flags.
     *
     * @param int $flags Set of flags
     */
    protected function unflagState($flags)
    {
        $this->state &= ~$flags;
    }

    /**
     * Checks is a flag is set.
     *
     * @param int $flags Flag
     * @return Boolean
     */
    protected function checkState($flags)
    {
        return ($this->state & $flags) === $flags;
    }

    /**
     * Checks if the passed client instance satisfies the required conditions
     * needed to initialize a transaction context.
     *
     * @param ClientInterface Client instance used by the context.
     */
    private function checkCapabilities(ClientInterface $client)
    {
        if ($client->getConnection() instanceof AggregatedConnectionInterface) {
            throw new NotSupportedException('Cannot initialize a MULTI/EXEC context when using aggregated connections');
        }

        $profile = $client->getProfile();

        if ($profile->supportsCommands(array('multi', 'exec', 'discard')) === false) {
            throw new NotSupportedException('The current profile does not support MULTI, EXEC and DISCARD');
        }

        $this->canWatch = $profile->supportsCommands(array('watch', 'unwatch'));
    }

    /**
     * Checks if WATCH and UNWATCH are supported by the server profile.
     */
    private function isWatchSupported()
    {
        if ($this->canWatch === false) {
            throw new NotSupportedException('The current profile does not support WATCH and UNWATCH');
        }
    }

    /**
     * Resets the state of a transaction.
     */
    protected function reset()
    {
        $this->setState(self::STATE_RESET);
        $this->commands = new SplQueue();
    }

    /**
     * Initializes a new transaction.
     */
    protected function initialize()
    {
        if ($this->checkState(self::STATE_INITIALIZED)) {
            return;
        }

        $options = $this->options;

        if (isset($options['cas']) && $options['cas']) {
            $this->flagState(self::STATE_CAS);
        }
        if (isset($options['watch'])) {
            $this->watch($options['watch']);
        }

        $cas = $this->checkState(self::STATE_CAS);
        $discarded = $this->checkState(self::STATE_DISCARDED);

        if (!$cas || ($cas && $discarded)) {
            $this->client->multi();

            if ($discarded) {
                $this->unflagState(self::STATE_CAS);
            }
        }

        $this->unflagState(self::STATE_DISCARDED);
        $this->flagState(self::STATE_INITIALIZED);
    }

    /**
     * Dynamically invokes a Redis command with the specified arguments.
     *
     * @param string $method Command ID.
     * @param array $arguments Arguments for the command.
     * @return mixed
     */
    public function __call($method, $arguments)
    {
        $command = $this->client->createCommand($method, $arguments);
        $response = $this->executeCommand($command);

        return $response;
    }

    /**
     * Executes the specified Redis command.
     *
     * @param CommandInterface $command A Redis command.
     * @return mixed
     */
    public function executeCommand(CommandInterface $command)
    {
        $this->initialize();
        $response = $this->client->executeCommand($command);

        if ($this->checkState(self::STATE_CAS)) {
            return $response;
        }

        if (!$response instanceof ResponseQueued) {
            $this->onProtocolError('The server did not respond with a QUEUED status reply');
        }

        $this->commands->enqueue($command);

        return $this;
    }

    /**
     * Executes WATCH on one or more keys.
     *
     * @param string|array $keys One or more keys.
     * @return mixed
     */
    public function watch($keys)
    {
        $this->isWatchSupported();

        if ($this->checkState(self::STATE_INITIALIZED) && !$this->checkState(self::STATE_CAS)) {
            throw new ClientException('WATCH after MULTI is not allowed');
        }

        $reply = $this->client->watch($keys);
        $this->flagState(self::STATE_WATCH);

        return $reply;
    }

    /**
     * Finalizes the transaction on the server by executing MULTI on the server.
     *
     * @return MultiExecContext
     */
    public function multi()
    {
        if ($this->checkState(self::STATE_INITIALIZED | self::STATE_CAS)) {
            $this->unflagState(self::STATE_CAS);
            $this->client->multi();
        } else {
            $this->initialize();
        }

        return $this;
    }

    /**
     * Executes UNWATCH.
     *
     * @return MultiExecContext
     */
    public function unwatch()
    {
        $this->isWatchSupported();
        $this->unflagState(self::STATE_WATCH);
        $this->__call('unwatch', array());

        return $this;
    }

    /**
     * Resets a transaction by UNWATCHing the keys that are being WATCHed and
     * DISCARDing the pending commands that have been already sent to the server.
     *
     * @return MultiExecContext
     */
    public function discard()
    {
        if ($this->checkState(self::STATE_INITIALIZED)) {
            $command = $this->checkState(self::STATE_CAS) ? 'unwatch' : 'discard';
            $this->client->$command();
            $this->reset();
            $this->flagState(self::STATE_DISCARDED);
        }

        return $this;
    }

    /**
     * Executes the whole transaction.
     *
     * @return mixed
     */
    public function exec()
    {
        return $this->execute();
    }

    /**
     * Checks the state of the transaction before execution.
     *
     * @param mixed $callable Callback for execution.
     */
    private function checkBeforeExecution($callable)
    {
        if ($this->checkState(self::STATE_INSIDEBLOCK)) {
            throw new ClientException("Cannot invoke 'execute' or 'exec' inside an active client transaction block");
        }

        if ($callable) {
            if (!is_callable($callable)) {
                throw new \InvalidArgumentException('Argument passed must be a callable object');
            }

            if (!$this->commands->isEmpty()) {
                $this->discard();
                throw new ClientException('Cannot execute a transaction block after using fluent interface');
            }
        }

        if (isset($this->options['retry']) && !isset($callable)) {
            $this->discard();
            throw new \InvalidArgumentException('Automatic retries can be used only when a transaction block is provided');
        }
    }

    /**
     * Handles the actual execution of the whole transaction.
     *
     * @param mixed $callable Optional callback for execution.
     * @return array
     */
    public function execute($callable = null)
    {
        $this->checkBeforeExecution($callable);

        $reply = null;
        $values = array();
        $attempts = isset($this->options['retry']) ? (int) $this->options['retry'] : 0;

        do {
            if ($callable !== null) {
                $this->executeTransactionBlock($callable);
            }

            if ($this->commands->isEmpty()) {
                if ($this->checkState(self::STATE_WATCH)) {
                    $this->discard();
                }

                return;
            }

            $reply = $this->client->exec();

            if ($reply === null) {
                if ($attempts === 0) {
                    $message = 'The current transaction has been aborted by the server';
                    throw new AbortedMultiExecException($this, $message);
                }

                $this->reset();

                if (isset($this->options['on_retry']) && is_callable($this->options['on_retry'])) {
                    call_user_func($this->options['on_retry'], $this, $attempts);
                }

                continue;
            }

            break;
        } while ($attempts-- > 0);

        $exec = $reply instanceof \Iterator ? iterator_to_array($reply) : $reply;
        $commands = $this->commands;

        $size = count($exec);
        if ($size !== count($commands)) {
            $this->onProtocolError("EXEC returned an unexpected number of replies");
        }

        $clientOpts = $this->client->getOptions();
        $useExceptions = isset($clientOpts->exceptions) ? $clientOpts->exceptions : true;

        for ($i = 0; $i < $size; $i++) {
            $commandReply = $exec[$i];

            if ($commandReply instanceof ResponseErrorInterface && $useExceptions) {
                $message = $commandReply->getMessage();
                throw new ServerException($message);
            }

            if ($commandReply instanceof \Iterator) {
                $commandReply = iterator_to_array($commandReply);
            }

            $values[$i] = $commands->dequeue()->parseResponse($commandReply);
        }

        return $values;
    }

    /**
     * Passes the current transaction context to a callable block for execution.
     *
     * @param mixed $callable Callback.
     */
    protected function executeTransactionBlock($callable)
    {
        $blockException = null;
        $this->flagState(self::STATE_INSIDEBLOCK);

        try {
            call_user_func($callable, $this);
        } catch (CommunicationException $exception) {
            $blockException = $exception;
        } catch (ServerException $exception) {
            $blockException = $exception;
        } catch (\Exception $exception) {
            $blockException = $exception;
            $this->discard();
        }

        $this->unflagState(self::STATE_INSIDEBLOCK);

        if ($blockException !== null) {
            throw $blockException;
        }
    }

    /**
     * Helper method that handles protocol errors encountered inside a transaction.
     *
     * @param string $message Error message.
     */
    private function onProtocolError($message)
    {
        // Since a MULTI/EXEC block cannot be initialized when using aggregated
        // connections, we can safely assume that Predis\Client::getConnection()
        // will always return an instance of Predis\Connection\SingleConnectionInterface.
        CommunicationException::handle(new ProtocolException(
            $this->client->getConnection(), $message
        ));
    }
}