aboutsummaryrefslogtreecommitdiffstats
path: root/library/symfony/process/Process.php
blob: c1e732170f9220dca10bd0ae4c83751a66e6db14 (plain) (blame)
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
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
<?php

/*
 * This file is part of the Symfony package.
 *
 * (c) Fabien Potencier <fabien@symfony.com>
 *
 * For the full copyright and license information, please view the LICENSE
 * file that was distributed with this source code.
 */

namespace Symfony\Component\Process;

use Symfony\Component\Process\Exception\InvalidArgumentException;
use Symfony\Component\Process\Exception\LogicException;
use Symfony\Component\Process\Exception\ProcessFailedException;
use Symfony\Component\Process\Exception\ProcessTimedOutException;
use Symfony\Component\Process\Exception\RuntimeException;
use Symfony\Component\Process\Pipes\PipesInterface;
use Symfony\Component\Process\Pipes\UnixPipes;
use Symfony\Component\Process\Pipes\WindowsPipes;

/**
 * Process is a thin wrapper around proc_* functions to easily
 * start independent PHP processes.
 *
 * @author Fabien Potencier <fabien@symfony.com>
 * @author Romain Neutron <imprec@gmail.com>
 */
class Process
{
    const ERR = 'err';
    const OUT = 'out';

    const STATUS_READY = 'ready';
    const STATUS_STARTED = 'started';
    const STATUS_TERMINATED = 'terminated';

    const STDIN = 0;
    const STDOUT = 1;
    const STDERR = 2;

    // Timeout Precision in seconds.
    const TIMEOUT_PRECISION = 0.2;

    private $callback;
    private $commandline;
    private $cwd;
    private $env;
    private $input;
    private $starttime;
    private $lastOutputTime;
    private $timeout;
    private $idleTimeout;
    private $options;
    private $exitcode;
    private $fallbackExitcode;
    private $processInformation;
    private $outputDisabled = false;
    private $stdout;
    private $stderr;
    private $enhanceWindowsCompatibility = true;
    private $enhanceSigchildCompatibility;
    private $process;
    private $status = self::STATUS_READY;
    private $incrementalOutputOffset = 0;
    private $incrementalErrorOutputOffset = 0;
    private $tty;
    private $pty;

    private $useFileHandles = false;
    /** @var PipesInterface */
    private $processPipes;

    private $latestSignal;

    private static $sigchild;

    /**
     * Exit codes translation table.
     *
     * User-defined errors must use exit codes in the 64-113 range.
     *
     * @var array
     */
    public static $exitCodes = array(
        0 => 'OK',
        1 => 'General error',
        2 => 'Misuse of shell builtins',

        126 => 'Invoked command cannot execute',
        127 => 'Command not found',
        128 => 'Invalid exit argument',

        // signals
        129 => 'Hangup',
        130 => 'Interrupt',
        131 => 'Quit and dump core',
        132 => 'Illegal instruction',
        133 => 'Trace/breakpoint trap',
        134 => 'Process aborted',
        135 => 'Bus error: "access to undefined portion of memory object"',
        136 => 'Floating point exception: "erroneous arithmetic operation"',
        137 => 'Kill (terminate immediately)',
        138 => 'User-defined 1',
        139 => 'Segmentation violation',
        140 => 'User-defined 2',
        141 => 'Write to pipe with no one reading',
        142 => 'Signal raised by alarm',
        143 => 'Termination (request to terminate)',
        // 144 - not defined
        145 => 'Child process terminated, stopped (or continued*)',
        146 => 'Continue if stopped',
        147 => 'Stop executing temporarily',
        148 => 'Terminal stop signal',
        149 => 'Background process attempting to read from tty ("in")',
        150 => 'Background process attempting to write to tty ("out")',
        151 => 'Urgent data available on socket',
        152 => 'CPU time limit exceeded',
        153 => 'File size limit exceeded',
        154 => 'Signal raised by timer counting virtual time: "virtual timer expired"',
        155 => 'Profiling timer expired',
        // 156 - not defined
        157 => 'Pollable event',
        // 158 - not defined
        159 => 'Bad syscall',
    );

    /**
     * Constructor.
     *
     * @param string         $commandline The command line to run
     * @param string|null    $cwd         The working directory or null to use the working dir of the current PHP process
     * @param array|null     $env         The environment variables or null to use the same environment as the current PHP process
     * @param string|null    $input       The input
     * @param int|float|null $timeout     The timeout in seconds or null to disable
     * @param array          $options     An array of options for proc_open
     *
     * @throws RuntimeException When proc_open is not installed
     */
    public function __construct($commandline, $cwd = null, array $env = null, $input = null, $timeout = 60, array $options = array())
    {
        if (!function_exists('proc_open')) {
            throw new RuntimeException('The Process class relies on proc_open, which is not available on your PHP installation.');
        }

        $this->commandline = $commandline;
        $this->cwd = $cwd;

        // on Windows, if the cwd changed via chdir(), proc_open defaults to the dir where PHP was started
        // on Gnu/Linux, PHP builds with --enable-maintainer-zts are also affected
        // @see : https://bugs.php.net/bug.php?id=51800
        // @see : https://bugs.php.net/bug.php?id=50524
        if (null === $this->cwd && (defined('ZEND_THREAD_SAFE') || '\\' === DIRECTORY_SEPARATOR)) {
            $this->cwd = getcwd();
        }
        if (null !== $env) {
            $this->setEnv($env);
        }

        $this->input = $input;
        $this->setTimeout($timeout);
        $this->useFileHandles = '\\' === DIRECTORY_SEPARATOR;
        $this->pty = false;
        $this->enhanceWindowsCompatibility = true;
        $this->enhanceSigchildCompatibility = '\\' !== DIRECTORY_SEPARATOR && $this->isSigchildEnabled();
        $this->options = array_replace(array('suppress_errors' => true, 'binary_pipes' => true), $options);
    }

    public function __destruct()
    {
        // stop() will check if we have a process running.
        $this->stop();
    }

    public function __clone()
    {
        $this->resetProcessData();
    }

    /**
     * Runs the process.
     *
     * The callback receives the type of output (out or err) and
     * some bytes from the output in real-time. It allows to have feedback
     * from the independent process during execution.
     *
     * The STDOUT and STDERR are also available after the process is finished
     * via the getOutput() and getErrorOutput() methods.
     *
     * @param callable|null $callback A PHP callback to run whenever there is some
     *                                output available on STDOUT or STDERR
     *
     * @return int The exit status code
     *
     * @throws RuntimeException When process can't be launched
     * @throws RuntimeException When process stopped after receiving signal
     * @throws LogicException   In case a callback is provided and output has been disabled
     */
    public function run($callback = null)
    {
        $this->start($callback);

        return $this->wait();
    }

    /**
     * Runs the process.
     *
     * This is identical to run() except that an exception is thrown if the process
     * exits with a non-zero exit code.
     *
     * @param callable|null $callback
     *
     * @return self
     *
     * @throws RuntimeException       if PHP was compiled with --enable-sigchild and the enhanced sigchild compatibility mode is not enabled
     * @throws ProcessFailedException if the process didn't terminate successfully
     */
    public function mustRun($callback = null)
    {
        if ($this->isSigchildEnabled() && !$this->enhanceSigchildCompatibility) {
            throw new RuntimeException('This PHP has been compiled with --enable-sigchild. You must use setEnhanceSigchildCompatibility() to use this method.');
        }

        if (0 !== $this->run($callback)) {
            throw new ProcessFailedException($this);
        }

        return $this;
    }

    /**
     * Starts the process and returns after writing the input to STDIN.
     *
     * This method blocks until all STDIN data is sent to the process then it
     * returns while the process runs in the background.
     *
     * The termination of the process can be awaited with wait().
     *
     * The callback receives the type of output (out or err) and some bytes from
     * the output in real-time while writing the standard input to the process.
     * It allows to have feedback from the independent process during execution.
     * If there is no callback passed, the wait() method can be called
     * with true as a second parameter then the callback will get all data occurred
     * in (and since) the start call.
     *
     * @param callable|null $callback A PHP callback to run whenever there is some
     *                                output available on STDOUT or STDERR
     *
     * @throws RuntimeException When process can't be launched
     * @throws RuntimeException When process is already running
     * @throws LogicException   In case a callback is provided and output has been disabled
     */
    public function start($callback = null)
    {
        if ($this->isRunning()) {
            throw new RuntimeException('Process is already running');
        }
        if ($this->outputDisabled && null !== $callback) {
            throw new LogicException('Output has been disabled, enable it to allow the use of a callback.');
        }

        $this->resetProcessData();
        $this->starttime = $this->lastOutputTime = microtime(true);
        $this->callback = $this->buildCallback($callback);
        $descriptors = $this->getDescriptors();

        $commandline = $this->commandline;

        if ('\\' === DIRECTORY_SEPARATOR && $this->enhanceWindowsCompatibility) {
            $commandline = 'cmd /V:ON /E:ON /D /C "('.$commandline.')';
            foreach ($this->processPipes->getFiles() as $offset => $filename) {
                $commandline .= ' '.$offset.'>'.ProcessUtils::escapeArgument($filename);
            }
            $commandline .= '"';

            if (!isset($this->options['bypass_shell'])) {
                $this->options['bypass_shell'] = true;
            }
        }

        $ptsWorkaround = null;

        if (!$this->useFileHandles && $this->enhanceSigchildCompatibility && $this->isSigchildEnabled()) {
            // Workaround for the bug, when PTS functionality is enabled.
            // @see : https://bugs.php.net/69442
            $ptsWorkaround = fopen(__FILE__, 'r');
        }

        $this->process = proc_open($commandline, $descriptors, $this->processPipes->pipes, $this->cwd, $this->env, $this->options);

        if ($ptsWorkaround) {
            fclose($ptsWorkaround);
        }

        if (!is_resource($this->process)) {
            throw new RuntimeException('Unable to launch a new process.');
        }
        $this->status = self::STATUS_STARTED;

        if ($this->tty) {
            return;
        }

        $this->updateStatus(false);
        $this->checkTimeout();
    }

    /**
     * Restarts the process.
     *
     * Be warned that the process is cloned before being started.
     *
     * @param callable|null $callback A PHP callback to run whenever there is some
     *                                output available on STDOUT or STDERR
     *
     * @return Process The new process
     *
     * @throws RuntimeException When process can't be launched
     * @throws RuntimeException When process is already running
     *
     * @see start()
     */
    public function restart($callback = null)
    {
        if ($this->isRunning()) {
            throw new RuntimeException('Process is already running');
        }

        $process = clone $this;
        $process->start($callback);

        return $process;
    }

    /**
     * Waits for the process to terminate.
     *
     * The callback receives the type of output (out or err) and some bytes
     * from the output in real-time while writing the standard input to the process.
     * It allows to have feedback from the independent process during execution.
     *
     * @param callable|null $callback A valid PHP callback
     *
     * @return int The exitcode of the process
     *
     * @throws RuntimeException When process timed out
     * @throws RuntimeException When process stopped after receiving signal
     * @throws LogicException   When process is not yet started
     */
    public function wait($callback = null)
    {
        $this->requireProcessIsStarted(__FUNCTION__);

        $this->updateStatus(false);
        if (null !== $callback) {
            $this->callback = $this->buildCallback($callback);
        }

        do {
            $this->checkTimeout();
            $running = '\\' === DIRECTORY_SEPARATOR ? $this->isRunning() : $this->processPipes->areOpen();
            $close = '\\' !== DIRECTORY_SEPARATOR || !$running;
            $this->readPipes(true, $close);
        } while ($running);

        while ($this->isRunning()) {
            usleep(1000);
        }

        if ($this->processInformation['signaled'] && $this->processInformation['termsig'] !== $this->latestSignal) {
            throw new RuntimeException(sprintf('The process has been signaled with signal "%s".', $this->processInformation['termsig']));
        }

        return $this->exitcode;
    }

    /**
     * Returns the Pid (process identifier), if applicable.
     *
     * @return int|null The process id if running, null otherwise
     *
     * @throws RuntimeException In case --enable-sigchild is activated
     */
    public function getPid()
    {
        if ($this->isSigchildEnabled()) {
            throw new RuntimeException('This PHP has been compiled with --enable-sigchild. The process identifier can not be retrieved.');
        }

        $this->updateStatus(false);

        return $this->isRunning() ? $this->processInformation['pid'] : null;
    }

    /**
     * Sends a POSIX signal to the process.
     *
     * @param int $signal A valid POSIX signal (see http://www.php.net/manual/en/pcntl.constants.php)
     *
     * @return Process
     *
     * @throws LogicException   In case the process is not running
     * @throws RuntimeException In case --enable-sigchild is activated
     * @throws RuntimeException In case of failure
     */
    public function signal($signal)
    {
        $this->doSignal($signal, true);

        return $this;
    }

    /**
     * Disables fetching output and error output from the underlying process.
     *
     * @return Process
     *
     * @throws RuntimeException In case the process is already running
     * @throws LogicException   if an idle timeout is set
     */
    public function disableOutput()
    {
        if ($this->isRunning()) {
            throw new RuntimeException('Disabling output while the process is running is not possible.');
        }
        if (null !== $this->idleTimeout) {
            throw new LogicException('Output can not be disabled while an idle timeout is set.');
        }

        $this->outputDisabled = true;

        return $this;
    }

    /**
     * Enables fetching output and error output from the underlying process.
     *
     * @return Process
     *
     * @throws RuntimeException In case the process is already running
     */
    public function enableOutput()
    {
        if ($this->isRunning()) {
            throw new RuntimeException('Enabling output while the process is running is not possible.');
        }

        $this->outputDisabled = false;

        return $this;
    }

    /**
     * Returns true in case the output is disabled, false otherwise.
     *
     * @return bool
     */
    public function isOutputDisabled()
    {
        return $this->outputDisabled;
    }

    /**
     * Returns the current output of the process (STDOUT).
     *
     * @return string The process output
     *
     * @throws LogicException in case the output has been disabled
     * @throws LogicException In case the process is not started
     */
    public function getOutput()
    {
        if ($this->outputDisabled) {
            throw new LogicException('Output has been disabled.');
        }

        $this->requireProcessIsStarted(__FUNCTION__);

        $this->readPipes(false, '\\' === DIRECTORY_SEPARATOR ? !$this->processInformation['running'] : true);

        return $this->stdout;
    }

    /**
     * Returns the output incrementally.
     *
     * In comparison with the getOutput method which always return the whole
     * output, this one returns the new output since the last call.
     *
     * @throws LogicException in case the output has been disabled
     * @throws LogicException In case the process is not started
     *
     * @return string The process output since the last call
     */
    public function getIncrementalOutput()
    {
        $this->requireProcessIsStarted(__FUNCTION__);

        $data = $this->getOutput();

        $latest = substr($data, $this->incrementalOutputOffset);

        if (false === $latest) {
            return '';
        }

        $this->incrementalOutputOffset = strlen($data);

        return $latest;
    }

    /**
     * Clears the process output.
     *
     * @return Process
     */
    public function clearOutput()
    {
        $this->stdout = '';
        $this->incrementalOutputOffset = 0;

        return $this;
    }

    /**
     * Returns the current error output of the process (STDERR).
     *
     * @return string The process error output
     *
     * @throws LogicException in case the output has been disabled
     * @throws LogicException In case the process is not started
     */
    public function getErrorOutput()
    {
        if ($this->outputDisabled) {
            throw new LogicException('Output has been disabled.');
        }

        $this->requireProcessIsStarted(__FUNCTION__);

        $this->readPipes(false, '\\' === DIRECTORY_SEPARATOR ? !$this->processInformation['running'] : true);

        return $this->stderr;
    }

    /**
     * Returns the errorOutput incrementally.
     *
     * In comparison with the getErrorOutput method which always return the
     * whole error output, this one returns the new error output since the last
     * call.
     *
     * @throws LogicException in case the output has been disabled
     * @throws LogicException In case the process is not started
     *
     * @return string The process error output since the last call
     */
    public function getIncrementalErrorOutput()
    {
        $this->requireProcessIsStarted(__FUNCTION__);

        $data = $this->getErrorOutput();

        $latest = substr($data, $this->incrementalErrorOutputOffset);

        if (false === $latest) {
            return '';
        }

        $this->incrementalErrorOutputOffset = strlen($data);

        return $latest;
    }

    /**
     * Clears the process output.
     *
     * @return Process
     */
    public function clearErrorOutput()
    {
        $this->stderr = '';
        $this->incrementalErrorOutputOffset = 0;

        return $this;
    }

    /**
     * Returns the exit code returned by the process.
     *
     * @return null|int The exit status code, null if the Process is not terminated
     *
     * @throws RuntimeException In case --enable-sigchild is activated and the sigchild compatibility mode is disabled
     */
    public function getExitCode()
    {
        if ($this->isSigchildEnabled() && !$this->enhanceSigchildCompatibility) {
            throw new RuntimeException('This PHP has been compiled with --enable-sigchild. You must use setEnhanceSigchildCompatibility() to use this method.');
        }

        $this->updateStatus(false);

        return $this->exitcode;
    }

    /**
     * Returns a string representation for the exit code returned by the process.
     *
     * This method relies on the Unix exit code status standardization
     * and might not be relevant for other operating systems.
     *
     * @return null|string A string representation for the exit status code, null if the Process is not terminated.
     *
     * @throws RuntimeException In case --enable-sigchild is activated and the sigchild compatibility mode is disabled
     *
     * @see http://tldp.org/LDP/abs/html/exitcodes.html
     * @see http://en.wikipedia.org/wiki/Unix_signal
     */
    public function getExitCodeText()
    {
        if (null === $exitcode = $this->getExitCode()) {
            return;
        }

        return isset(self::$exitCodes[$exitcode]) ? self::$exitCodes[$exitcode] : 'Unknown error';
    }

    /**
     * Checks if the process ended successfully.
     *
     * @return bool true if the process ended successfully, false otherwise
     */
    public function isSuccessful()
    {
        return 0 === $this->getExitCode();
    }

    /**
     * Returns true if the child process has been terminated by an uncaught signal.
     *
     * It always returns false on Windows.
     *
     * @return bool
     *
     * @throws RuntimeException In case --enable-sigchild is activated
     * @throws LogicException   In case the process is not terminated
     */
    public function hasBeenSignaled()
    {
        $this->requireProcessIsTerminated(__FUNCTION__);

        if ($this->isSigchildEnabled()) {
            throw new RuntimeException('This PHP has been compiled with --enable-sigchild. Term signal can not be retrieved.');
        }

        $this->updateStatus(false);

        return $this->processInformation['signaled'];
    }

    /**
     * Returns the number of the signal that caused the child process to terminate its execution.
     *
     * It is only meaningful if hasBeenSignaled() returns true.
     *
     * @return int
     *
     * @throws RuntimeException In case --enable-sigchild is activated
     * @throws LogicException   In case the process is not terminated
     */
    public function getTermSignal()
    {
        $this->requireProcessIsTerminated(__FUNCTION__);

        if ($this->isSigchildEnabled()) {
            throw new RuntimeException('This PHP has been compiled with --enable-sigchild. Term signal can not be retrieved.');
        }

        $this->updateStatus(false);

        return $this->processInformation['termsig'];
    }

    /**
     * Returns true if the child process has been stopped by a signal.
     *
     * It always returns false on Windows.
     *
     * @return bool
     *
     * @throws LogicException In case the process is not terminated
     */
    public function hasBeenStopped()
    {
        $this->requireProcessIsTerminated(__FUNCTION__);

        $this->updateStatus(false);

        return $this->processInformation['stopped'];
    }

    /**
     * Returns the number of the signal that caused the child process to stop its execution.
     *
     * It is only meaningful if hasBeenStopped() returns true.
     *
     * @return int
     *
     * @throws LogicException In case the process is not terminated
     */
    public function getStopSignal()
    {
        $this->requireProcessIsTerminated(__FUNCTION__);

        $this->updateStatus(false);

        return $this->processInformation['stopsig'];
    }

    /**
     * Checks if the process is currently running.
     *
     * @return bool true if the process is currently running, false otherwise
     */
    public function isRunning()
    {
        if (self::STATUS_STARTED !== $this->status) {
            return false;
        }

        $this->updateStatus(false);

        return $this->processInformation['running'];
    }

    /**
     * Checks if the process has been started with no regard to the current state.
     *
     * @return bool true if status is ready, false otherwise
     */
    public function isStarted()
    {
        return $this->status != self::STATUS_READY;
    }

    /**
     * Checks if the process is terminated.
     *
     * @return bool true if process is terminated, false otherwise
     */
    public function isTerminated()
    {
        $this->updateStatus(false);

        return $this->status == self::STATUS_TERMINATED;
    }

    /**
     * Gets the process status.
     *
     * The status is one of: ready, started, terminated.
     *
     * @return string The current process status
     */
    public function getStatus()
    {
        $this->updateStatus(false);

        return $this->status;
    }

    /**
     * Stops the process.
     *
     * @param int|float $timeout The timeout in seconds
     * @param int       $signal  A POSIX signal to send in case the process has not stop at timeout, default is SIGKILL (9)
     *
     * @return int The exit-code of the process
     */
    public function stop($timeout = 10, $signal = null)
    {
        $timeoutMicro = microtime(true) + $timeout;
        if ($this->isRunning()) {
            // given `SIGTERM` may not be defined and that `proc_terminate` uses the constant value and not the constant itself, we use the same here
            $this->doSignal(15, false);
            do {
                usleep(1000);
            } while ($this->isRunning() && microtime(true) < $timeoutMicro);

            if ($this->isRunning() && !$this->isSigchildEnabled()) {
                // Avoid exception here: process is supposed to be running, but it might have stopped just
                // after this line. In any case, let's silently discard the error, we cannot do anything.
                $this->doSignal($signal ?: 9, false);
            }
        }

        $this->updateStatus(false);
        if ($this->processInformation['running']) {
            $this->close();
        }

        return $this->exitcode;
    }

    /**
     * Adds a line to the STDOUT stream.
     *
     * @param string $line The line to append
     */
    public function addOutput($line)
    {
        $this->lastOutputTime = microtime(true);
        $this->stdout .= $line;
    }

    /**
     * Adds a line to the STDERR stream.
     *
     * @param string $line The line to append
     */
    public function addErrorOutput($line)
    {
        $this->lastOutputTime = microtime(true);
        $this->stderr .= $line;
    }

    /**
     * Gets the command line to be executed.
     *
     * @return string The command to execute
     */
    public function getCommandLine()
    {
        return $this->commandline;
    }

    /**
     * Sets the command line to be executed.
     *
     * @param string $commandline The command to execute
     *
     * @return self The current Process instance
     */
    public function setCommandLine($commandline)
    {
        $this->commandline = $commandline;

        return $this;
    }

    /**
     * Gets the process timeout (max. runtime).
     *
     * @return float|null The timeout in seconds or null if it's disabled
     */
    public function getTimeout()
    {
        return $this->timeout;
    }

    /**
     * Gets the process idle timeout (max. time since last output).
     *
     * @return float|null The timeout in seconds or null if it's disabled
     */
    public function getIdleTimeout()
    {
        return $this->idleTimeout;
    }

    /**
     * Sets the process timeout (max. runtime).
     *
     * To disable the timeout, set this value to null.
     *
     * @param int|float|null $timeout The timeout in seconds
     *
     * @return self The current Process instance
     *
     * @throws InvalidArgumentException if the timeout is negative
     */
    public function setTimeout($timeout)
    {
        $this->timeout = $this->validateTimeout($timeout);

        return $this;
    }

    /**
     * Sets the process idle timeout (max. time since last output).
     *
     * To disable the timeout, set this value to null.
     *
     * @param int|float|null $timeout The timeout in seconds
     *
     * @return self The current Process instance.
     *
     * @throws LogicException           if the output is disabled
     * @throws InvalidArgumentException if the timeout is negative
     */
    public function setIdleTimeout($timeout)
    {
        if (null !== $timeout && $this->outputDisabled) {
            throw new LogicException('Idle timeout can not be set while the output is disabled.');
        }

        $this->idleTimeout = $this->validateTimeout($timeout);

        return $this;
    }

    /**
     * Enables or disables the TTY mode.
     *
     * @param bool $tty True to enabled and false to disable
     *
     * @return self The current Process instance
     *
     * @throws RuntimeException In case the TTY mode is not supported
     */
    public function setTty($tty)
    {
        if ('\\' === DIRECTORY_SEPARATOR && $tty) {
            throw new RuntimeException('TTY mode is not supported on Windows platform.');
        }
        if ($tty && (!file_exists('/dev/tty') || !is_readable('/dev/tty'))) {
            throw new RuntimeException('TTY mode requires /dev/tty to be readable.');
        }

        $this->tty = (bool) $tty;

        return $this;
    }

    /**
     * Checks if the TTY mode is enabled.
     *
     * @return bool true if the TTY mode is enabled, false otherwise
     */
    public function isTty()
    {
        return $this->tty;
    }

    /**
     * Sets PTY mode.
     *
     * @param bool $bool
     *
     * @return self
     */
    public function setPty($bool)
    {
        $this->pty = (bool) $bool;

        return $this;
    }

    /**
     * Returns PTY state.
     *
     * @return bool
     */
    public function isPty()
    {
        return $this->pty;
    }

    /**
     * Gets the working directory.
     *
     * @return string|null The current working directory or null on failure
     */
    public function getWorkingDirectory()
    {
        if (null === $this->cwd) {
            // getcwd() will return false if any one of the parent directories does not have
            // the readable or search mode set, even if the current directory does
            return getcwd() ?: null;
        }

        return $this->cwd;
    }

    /**
     * Sets the current working directory.
     *
     * @param string $cwd The new working directory
     *
     * @return self The current Process instance
     */
    public function setWorkingDirectory($cwd)
    {
        $this->cwd = $cwd;

        return $this;
    }

    /**
     * Gets the environment variables.
     *
     * @return array The current environment variables
     */
    public function getEnv()
    {
        return $this->env;
    }

    /**
     * Sets the environment variables.
     *
     * An environment variable value should be a string.
     * If it is an array, the variable is ignored.
     *
     * That happens in PHP when 'argv' is registered into
     * the $_ENV array for instance.
     *
     * @param array $env The new environment variables
     *
     * @return self The current Process instance
     */
    public function setEnv(array $env)
    {
        // Process can not handle env values that are arrays
        $env = array_filter($env, function ($value) {
            return !is_array($value);
        });

        $this->env = array();
        foreach ($env as $key => $value) {
            $this->env[$key] = (string) $value;
        }

        return $this;
    }

    /**
     * Gets the contents of STDIN.
     *
     * @return string|null The current contents
     *
     * @deprecated since version 2.5, to be removed in 3.0.
     *             Use setInput() instead.
     *             This method is deprecated in favor of getInput.
     */
    public function getStdin()
    {
        @trigger_error('The '.__METHOD__.' method is deprecated since version 2.5 and will be removed in 3.0. Use the getInput() method instead.', E_USER_DEPRECATED);

        return $this->getInput();
    }

    /**
     * Gets the Process input.
     *
     * @return null|string The Process input
     */
    public function getInput()
    {
        return $this->input;
    }

    /**
     * Sets the contents of STDIN.
     *
     * @param string|null $stdin The new contents
     *
     * @return self The current Process instance
     *
     * @deprecated since version 2.5, to be removed in 3.0.
     *             Use setInput() instead.
     *
     * @throws LogicException           In case the process is running
     * @throws InvalidArgumentException In case the argument is invalid
     */
    public function setStdin($stdin)
    {
        @trigger_error('The '.__METHOD__.' method is deprecated since version 2.5 and will be removed in 3.0. Use the setInput() method instead.', E_USER_DEPRECATED);

        return $this->setInput($stdin);
    }

    /**
     * Sets the input.
     *
     * This content will be passed to the underlying process standard input.
     *
     * @param mixed $input The content
     *
     * @return self The current Process instance
     *
     * @throws LogicException In case the process is running
     *
     * Passing an object as an input is deprecated since version 2.5 and will be removed in 3.0.
     */
    public function setInput($input)
    {
        if ($this->isRunning()) {
            throw new LogicException('Input can not be set while the process is running.');
        }

        $this->input = ProcessUtils::validateInput(sprintf('%s::%s', __CLASS__, __FUNCTION__), $input);

        return $this;
    }

    /**
     * Gets the options for proc_open.
     *
     * @return array The current options
     */
    public function getOptions()
    {
        return $this->options;
    }

    /**
     * Sets the options for proc_open.
     *
     * @param array $options The new options
     *
     * @return self The current Process instance
     */
    public function setOptions(array $options)
    {
        $this->options = $options;

        return $this;
    }

    /**
     * Gets whether or not Windows compatibility is enabled.
     *
     * This is true by default.
     *
     * @return bool
     */
    public function getEnhanceWindowsCompatibility()
    {
        return $this->enhanceWindowsCompatibility;
    }

    /**
     * Sets whether or not Windows compatibility is enabled.
     *
     * @param bool $enhance
     *
     * @return self The current Process instance
     */
    public function setEnhanceWindowsCompatibility($enhance)
    {
        $this->enhanceWindowsCompatibility = (bool) $enhance;

        return $this;
    }

    /**
     * Returns whether sigchild compatibility mode is activated or not.
     *
     * @return bool
     */
    public function getEnhanceSigchildCompatibility()
    {
        return $this->enhanceSigchildCompatibility;
    }

    /**
     * Activates sigchild compatibility mode.
     *
     * Sigchild compatibility mode is required to get the exit code and
     * determine the success of a process when PHP has been compiled with
     * the --enable-sigchild option
     *
     * @param bool $enhance
     *
     * @return self The current Process instance
     */
    public function setEnhanceSigchildCompatibility($enhance)
    {
        $this->enhanceSigchildCompatibility = (bool) $enhance;

        return $this;
    }

    /**
     * Performs a check between the timeout definition and the time the process started.
     *
     * In case you run a background process (with the start method), you should
     * trigger this method regularly to ensure the process timeout
     *
     * @throws ProcessTimedOutException In case the timeout was reached
     */
    public function checkTimeout()
    {
        if ($this->status !== self::STATUS_STARTED) {
            return;
        }

        if (null !== $this->timeout && $this->timeout < microtime(true) - $this->starttime) {
            $this->stop(0);

            throw new ProcessTimedOutException($this, ProcessTimedOutException::TYPE_GENERAL);
        }

        if (null !== $this->idleTimeout && $this->idleTimeout < microtime(true) - $this->lastOutputTime) {
            $this->stop(0);

            throw new ProcessTimedOutException($this, ProcessTimedOutException::TYPE_IDLE);
        }
    }

    /**
     * Returns whether PTY is supported on the current operating system.
     *
     * @return bool
     */
    public static function isPtySupported()
    {
        static $result;

        if (null !== $result) {
            return $result;
        }

        if ('\\' === DIRECTORY_SEPARATOR) {
            return $result = false;
        }

        $proc = @proc_open('echo 1', array(array('pty'), array('pty'), array('pty')), $pipes);
        if (is_resource($proc)) {
            proc_close($proc);

            return $result = true;
        }

        return $result = false;
    }

    /**
     * Creates the descriptors needed by the proc_open.
     *
     * @return array
     */
    private function getDescriptors()
    {
        if ('\\' === DIRECTORY_SEPARATOR) {
            $this->processPipes = WindowsPipes::create($this, $this->input);
        } else {
            $this->processPipes = UnixPipes::create($this, $this->input);
        }
        $descriptors = $this->processPipes->getDescriptors($this->outputDisabled);

        if (!$this->useFileHandles && $this->enhanceSigchildCompatibility && $this->isSigchildEnabled()) {
            // last exit code is output on the fourth pipe and caught to work around --enable-sigchild
            $descriptors = array_merge($descriptors, array(array('pipe', 'w')));

            $this->commandline = '('.$this->commandline.') 3>/dev/null; code=$?; echo $code >&3; exit $code';
        }

        return $descriptors;
    }

    /**
     * Builds up the callback used by wait().
     *
     * The callbacks adds all occurred output to the specific buffer and calls
     * the user callback (if present) with the received output.
     *
     * @param callable|null $callback The user defined PHP callback
     *
     * @return \Closure A PHP closure
     */
    protected function buildCallback($callback)
    {
        $that = $this;
        $out = self::OUT;
        $callback = function ($type, $data) use ($that, $callback, $out) {
            if ($out == $type) {
                $that->addOutput($data);
            } else {
                $that->addErrorOutput($data);
            }

            if (null !== $callback) {
                call_user_func($callback, $type, $data);
            }
        };

        return $callback;
    }

    /**
     * Updates the status of the process, reads pipes.
     *
     * @param bool $blocking Whether to use a blocking read call.
     */
    protected function updateStatus($blocking)
    {
        if (self::STATUS_STARTED !== $this->status) {
            return;
        }

        $this->processInformation = proc_get_status($this->process);
        $this->captureExitCode();

        $this->readPipes($blocking, '\\' === DIRECTORY_SEPARATOR ? !$this->processInformation['running'] : true);

        if (!$this->processInformation['running']) {
            $this->close();
        }
    }

    /**
     * Returns whether PHP has been compiled with the '--enable-sigchild' option or not.
     *
     * @return bool
     */
    protected function isSigchildEnabled()
    {
        if (null !== self::$sigchild) {
            return self::$sigchild;
        }

        if (!function_exists('phpinfo')) {
            return self::$sigchild = false;
        }

        ob_start();
        phpinfo(INFO_GENERAL);

        return self::$sigchild = false !== strpos(ob_get_clean(), '--enable-sigchild');
    }

    /**
     * Validates and returns the filtered timeout.
     *
     * @param int|float|null $timeout
     *
     * @return float|null
     *
     * @throws InvalidArgumentException if the given timeout is a negative number
     */
    private function validateTimeout($timeout)
    {
        $timeout = (float) $timeout;

        if (0.0 === $timeout) {
            $timeout = null;
        } elseif ($timeout < 0) {
            throw new InvalidArgumentException('The timeout value must be a valid positive integer or float number.');
        }

        return $timeout;
    }

    /**
     * Reads pipes, executes callback.
     *
     * @param bool $blocking Whether to use blocking calls or not.
     * @param bool $close    Whether to close file handles or not.
     */
    private function readPipes($blocking, $close)
    {
        $result = $this->processPipes->readAndWrite($blocking, $close);

        $callback = $this->callback;
        foreach ($result as $type => $data) {
            if (3 == $type) {
                $this->fallbackExitcode = (int) $data;
            } else {
                $callback($type === self::STDOUT ? self::OUT : self::ERR, $data);
            }
        }
    }

    /**
     * Captures the exitcode if mentioned in the process information.
     */
    private function captureExitCode()
    {
        if (isset($this->processInformation['exitcode']) && -1 != $this->processInformation['exitcode']) {
            $this->exitcode = $this->processInformation['exitcode'];
        }
    }

    /**
     * Closes process resource, closes file handles, sets the exitcode.
     *
     * @return int The exitcode
     */
    private function close()
    {
        $this->processPipes->close();
        if (is_resource($this->process)) {
            $exitcode = proc_close($this->process);
        } else {
            $exitcode = -1;
        }

        $this->exitcode = -1 !== $exitcode ? $exitcode : (null !== $this->exitcode ? $this->exitcode : -1);
        $this->status = self::STATUS_TERMINATED;

        if (-1 === $this->exitcode && null !== $this->fallbackExitcode) {
            $this->exitcode = $this->fallbackExitcode;
        } elseif (-1 === $this->exitcode && $this->processInformation['signaled'] && 0 < $this->processInformation['termsig']) {
            // if process has been signaled, no exitcode but a valid termsig, apply Unix convention
            $this->exitcode = 128 + $this->processInformation['termsig'];
        }

        return $this->exitcode;
    }

    /**
     * Resets data related to the latest run of the process.
     */
    private function resetProcessData()
    {
        $this->starttime = null;
        $this->callback = null;
        $this->exitcode = null;
        $this->fallbackExitcode = null;
        $this->processInformation = null;
        $this->stdout = null;
        $this->stderr = null;
        $this->process = null;
        $this->latestSignal = null;
        $this->status = self::STATUS_READY;
        $this->incrementalOutputOffset = 0;
        $this->incrementalErrorOutputOffset = 0;
    }

    /**
     * Sends a POSIX signal to the process.
     *
     * @param int  $signal         A valid POSIX signal (see http://www.php.net/manual/en/pcntl.constants.php)
     * @param bool $throwException Whether to throw exception in case signal failed
     *
     * @return bool True if the signal was sent successfully, false otherwise
     *
     * @throws LogicException   In case the process is not running
     * @throws RuntimeException In case --enable-sigchild is activated
     * @throws RuntimeException In case of failure
     */
    private function doSignal($signal, $throwException)
    {
        if (!$this->isRunning()) {
            if ($throwException) {
                throw new LogicException('Can not send signal on a non running process.');
            }

            return false;
        }

        if ($this->isSigchildEnabled()) {
            if ($throwException) {
                throw new RuntimeException('This PHP has been compiled with --enable-sigchild. The process can not be signaled.');
            }

            return false;
        }

        if ('\\' === DIRECTORY_SEPARATOR) {
            exec(sprintf('taskkill /F /T /PID %d 2>&1', $this->getPid()), $output, $exitCode);
            if ($exitCode) {
                if ($throwException) {
                    throw new RuntimeException(sprintf('Unable to kill the process (%s).', implode(' ', $output)));
                }

                return false;
            }
        }

        if (true !== @proc_terminate($this->process, $signal) && '\\' !== DIRECTORY_SEPARATOR) {
            if ($throwException) {
                throw new RuntimeException(sprintf('Error while sending signal `%s`.', $signal));
            }

            return false;
        }

        $this->latestSignal = $signal;

        return true;
    }

    /**
     * Ensures the process is running or terminated, throws a LogicException if the process has a not started.
     *
     * @param string $functionName The function name that was called.
     *
     * @throws LogicException If the process has not run.
     */
    private function requireProcessIsStarted($functionName)
    {
        if (!$this->isStarted()) {
            throw new LogicException(sprintf('Process must be started before calling %s.', $functionName));
        }
    }

    /**
     * Ensures the process is terminated, throws a LogicException if the process has a status different than `terminated`.
     *
     * @param string $functionName The function name that was called.
     *
     * @throws LogicException If the process is not yet terminated.
     */
    private function requireProcessIsTerminated($functionName)
    {
        if (!$this->isTerminated()) {
            throw new LogicException(sprintf('Process must be terminated before calling %s.', $functionName));
        }
    }
}