This file is indexed.

/usr/share/php/DB/mysql.php is in php-db 1.9.2-2ubuntu1.

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
 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
<?php

/* vim: set expandtab tabstop=4 shiftwidth=4 softtabstop=4: */

/**
 * The PEAR DB driver for PHP's mysql extension
 * for interacting with MySQL databases
 *
 * PHP version 5
 *
 * LICENSE: This source file is subject to version 3.0 of the PHP license
 * that is available through the world-wide-web at the following URI:
 * http://www.php.net/license/3_0.txt.  If you did not receive a copy of
 * the PHP License and are unable to obtain it through the web, please
 * send a note to license@php.net so we can mail you a copy immediately.
 *
 * @category   Database
 * @package    DB
 * @author     Stig Bakken <ssb@php.net>
 * @author     Daniel Convissor <danielc@php.net>
 * @copyright  1997-2007 The PHP Group
 * @license    http://www.php.net/license/3_0.txt  PHP License 3.0
 * @version    CVS: $Id$
 * @link       http://pear.php.net/package/DB
 */

/**
 * Obtain the DB_common class so it can be extended from
 */
require_once 'DB/common.php';

/**
 * The methods PEAR DB uses to interact with PHP's mysql extension
 * for interacting with MySQL databases
 *
 * These methods overload the ones declared in DB_common.
 *
 * @category   Database
 * @package    DB
 * @author     Stig Bakken <ssb@php.net>
 * @author     Daniel Convissor <danielc@php.net>
 * @copyright  1997-2007 The PHP Group
 * @license    http://www.php.net/license/3_0.txt  PHP License 3.0
 * @version    Release: 1.9.2
 * @link       http://pear.php.net/package/DB
 */
class DB_mysql extends DB_common
{
    // {{{ properties

    /**
     * The DB driver type (mysql, oci8, odbc, etc.)
     * @var string
     */
    var $phptype = 'mysql';

    /**
     * The database syntax variant to be used (db2, access, etc.), if any
     * @var string
     */
    var $dbsyntax = 'mysql';

    /**
     * The capabilities of this DB implementation
     *
     * The 'new_link' element contains the PHP version that first provided
     * new_link support for this DBMS.  Contains false if it's unsupported.
     *
     * Meaning of the 'limit' element:
     *   + 'emulate' = emulate with fetch row by number
     *   + 'alter'   = alter the query
     *   + false     = skip rows
     *
     * @var array
     */
    var $features = array(
        'limit'         => 'alter',
        'new_link'      => '4.2.0',
        'numrows'       => true,
        'pconnect'      => true,
        'prepare'       => false,
        'ssl'           => false,
        'transactions'  => true,
    );

    /**
     * A mapping of native error codes to DB error codes
     * @var array
     */
    var $errorcode_map = array(
        1004 => DB_ERROR_CANNOT_CREATE,
        1005 => DB_ERROR_CANNOT_CREATE,
        1006 => DB_ERROR_CANNOT_CREATE,
        1007 => DB_ERROR_ALREADY_EXISTS,
        1008 => DB_ERROR_CANNOT_DROP,
        1022 => DB_ERROR_ALREADY_EXISTS,
        1044 => DB_ERROR_ACCESS_VIOLATION,
        1046 => DB_ERROR_NODBSELECTED,
        1048 => DB_ERROR_CONSTRAINT,
        1049 => DB_ERROR_NOSUCHDB,
        1050 => DB_ERROR_ALREADY_EXISTS,
        1051 => DB_ERROR_NOSUCHTABLE,
        1054 => DB_ERROR_NOSUCHFIELD,
        1061 => DB_ERROR_ALREADY_EXISTS,
        1062 => DB_ERROR_ALREADY_EXISTS,
        1064 => DB_ERROR_SYNTAX,
        1091 => DB_ERROR_NOT_FOUND,
        1100 => DB_ERROR_NOT_LOCKED,
        1136 => DB_ERROR_VALUE_COUNT_ON_ROW,
        1142 => DB_ERROR_ACCESS_VIOLATION,
        1146 => DB_ERROR_NOSUCHTABLE,
        1216 => DB_ERROR_CONSTRAINT,
        1217 => DB_ERROR_CONSTRAINT,
        1356 => DB_ERROR_DIVZERO,
        1451 => DB_ERROR_CONSTRAINT,
        1452 => DB_ERROR_CONSTRAINT,
    );

    /**
     * The raw database connection created by PHP
     * @var resource
     */
    var $connection;

    /**
     * The DSN information for connecting to a database
     * @var array
     */
    var $dsn = array();


    /**
     * Should data manipulation queries be committed automatically?
     * @var bool
     * @access private
     */
    var $autocommit = true;

    /**
     * The quantity of transactions begun
     *
     * {@internal  While this is private, it can't actually be designated
     * private in PHP 5 because it is directly accessed in the test suite.}}
     *
     * @var integer
     * @access private
     */
    var $transaction_opcount = 0;

    /**
     * The database specified in the DSN
     *
     * It's a fix to allow calls to different databases in the same script.
     *
     * @var string
     * @access private
     */
    var $_db = '';


    // }}}
    // {{{ constructor

    /**
     * This constructor calls <kbd>parent::__construct()</kbd>
     *
     * @return void
     */
    function __construct()
    {
        parent::__construct();
    }

    // }}}
    // {{{ connect()

    /**
     * Connect to the database server, log in and open the database
     *
     * Don't call this method directly.  Use DB::connect() instead.
     *
     * PEAR DB's mysql driver supports the following extra DSN options:
     *   + new_link      If set to true, causes subsequent calls to connect()
     *                    to return a new connection link instead of the
     *                    existing one.  WARNING: this is not portable to
     *                    other DBMS's. Available since PEAR DB 1.7.0.
     *   + client_flags  Any combination of MYSQL_CLIENT_* constants.
     *                    Only used if PHP is at version 4.3.0 or greater.
     *                    Available since PEAR DB 1.7.0.
     *
     * @param array $dsn         the data source name
     * @param bool  $persistent  should the connection be persistent?
     *
     * @return int  DB_OK on success. A DB_Error object on failure.
     */
    function connect($dsn, $persistent = false)
    {
        if (!PEAR::loadExtension('mysql')) {
            return $this->raiseError(DB_ERROR_EXTENSION_NOT_FOUND);
        }

        $this->dsn = $dsn;
        if ($dsn['dbsyntax']) {
            $this->dbsyntax = $dsn['dbsyntax'];
        }

        $params = array();
        if ($dsn['protocol'] && $dsn['protocol'] == 'unix') {
            $params[0] = ':' . $dsn['socket'];
        } else {
            $params[0] = $dsn['hostspec'] ? $dsn['hostspec']
                         : 'localhost';
            if ($dsn['port']) {
                $params[0] .= ':' . $dsn['port'];
            }
        }
        $params[] = $dsn['username'] ? $dsn['username'] : null;
        $params[] = $dsn['password'] ? $dsn['password'] : null;

        if (!$persistent) {
            if (isset($dsn['new_link'])
                && ($dsn['new_link'] == 'true' || $dsn['new_link'] === true))
            {
                $params[] = true;
            } else {
                $params[] = false;
            }
        }
        if (version_compare(phpversion(), '4.3.0', '>=')) {
            $params[] = isset($dsn['client_flags'])
                        ? $dsn['client_flags'] : null;
        }

        $connect_function = $persistent ? 'mysql_pconnect' : 'mysql_connect';

        $ini = ini_get('track_errors');
        $php_errormsg = '';
        if ($ini) {
            $this->connection = @call_user_func_array($connect_function,
                                                      $params);
        } else {
            @ini_set('track_errors', 1);
            $this->connection = @call_user_func_array($connect_function,
                                                      $params);
            @ini_set('track_errors', $ini);
        }

        if (!$this->connection) {
            if (($err = @mysql_error()) != '') {
                return $this->raiseError(DB_ERROR_CONNECT_FAILED,
                                         null, null, null, 
                                         $err);
            } else {
                return $this->raiseError(DB_ERROR_CONNECT_FAILED,
                                         null, null, null,
                                         $php_errormsg);
            }
        }

        if ($dsn['database']) {
            if (!@mysql_select_db($dsn['database'], $this->connection)) {
                return $this->mysqlRaiseError();
            }
            $this->_db = $dsn['database'];
        }

        return DB_OK;
    }

    // }}}
    // {{{ disconnect()

    /**
     * Disconnects from the database server
     *
     * @return bool  TRUE on success, FALSE on failure
     */
    function disconnect()
    {
        $ret = @mysql_close($this->connection);
        $this->connection = null;
        return $ret;
    }

    // }}}
    // {{{ simpleQuery()

    /**
     * Sends a query to the database server
     *
     * Generally uses mysql_query().  If you want to use
     * mysql_unbuffered_query() set the "result_buffering" option to 0 using
     * setOptions().  This option was added in Release 1.7.0.
     *
     * @param string  the SQL query string
     *
     * @return mixed  + a PHP result resrouce for successful SELECT queries
     *                + the DB_OK constant for other successful queries
     *                + a DB_Error object on failure
     */
    function simpleQuery($query)
    {
        $ismanip = $this->_checkManip($query);
        $this->last_query = $query;
        $query = $this->modifyQuery($query);
        if ($this->_db) {
            if (!@mysql_select_db($this->_db, $this->connection)) {
                return $this->mysqlRaiseError(DB_ERROR_NODBSELECTED);
            }
        }
        if (!$this->autocommit && $ismanip) {
            if ($this->transaction_opcount == 0) {
                $result = @mysql_query('SET AUTOCOMMIT=0', $this->connection);
                $result = @mysql_query('BEGIN', $this->connection);
                if (!$result) {
                    return $this->mysqlRaiseError();
                }
            }
            $this->transaction_opcount++;
        }
        if (!$this->options['result_buffering']) {
            $result = @mysql_unbuffered_query($query, $this->connection);
        } else {
            $result = @mysql_query($query, $this->connection);
        }
        if (!$result) {
            return $this->mysqlRaiseError();
        }
        if (is_resource($result)) {
            return $result;
        }
        return DB_OK;
    }

    // }}}
    // {{{ nextResult()

    /**
     * Move the internal mysql result pointer to the next available result
     *
     * This method has not been implemented yet.
     *
     * @param a valid sql result resource
     *
     * @return false
     */
    function nextResult($result)
    {
        return false;
    }

    // }}}
    // {{{ fetchInto()

    /**
     * Places a row from the result set into the given array
     *
     * Formating of the array and the data therein are configurable.
     * See DB_result::fetchInto() for more information.
     *
     * This method is not meant to be called directly.  Use
     * DB_result::fetchInto() instead.  It can't be declared "protected"
     * because DB_result is a separate object.
     *
     * @param resource $result    the query result resource
     * @param array    $arr       the referenced array to put the data in
     * @param int      $fetchmode how the resulting array should be indexed
     * @param int      $rownum    the row number to fetch (0 = first row)
     *
     * @return mixed  DB_OK on success, NULL when the end of a result set is
     *                 reached or on failure
     *
     * @see DB_result::fetchInto()
     */
    function fetchInto($result, &$arr, $fetchmode, $rownum = null)
    {
        if ($rownum !== null) {
            if (!@mysql_data_seek($result, $rownum)) {
                return null;
            }
        }
        if ($fetchmode & DB_FETCHMODE_ASSOC) {
            $arr = @mysql_fetch_array($result, MYSQL_ASSOC);
            if ($this->options['portability'] & DB_PORTABILITY_LOWERCASE && $arr) {
                $arr = array_change_key_case($arr, CASE_LOWER);
            }
        } else {
            $arr = @mysql_fetch_row($result);
        }
        if (!$arr) {
            return null;
        }
        if ($this->options['portability'] & DB_PORTABILITY_RTRIM) {
            /*
             * Even though this DBMS already trims output, we do this because
             * a field might have intentional whitespace at the end that
             * gets removed by DB_PORTABILITY_RTRIM under another driver.
             */
            $this->_rtrimArrayValues($arr);
        }
        if ($this->options['portability'] & DB_PORTABILITY_NULL_TO_EMPTY) {
            $this->_convertNullArrayValuesToEmpty($arr);
        }
        return DB_OK;
    }

    // }}}
    // {{{ freeResult()

    /**
     * Deletes the result set and frees the memory occupied by the result set
     *
     * This method is not meant to be called directly.  Use
     * DB_result::free() instead.  It can't be declared "protected"
     * because DB_result is a separate object.
     *
     * @param resource $result  PHP's query result resource
     *
     * @return bool  TRUE on success, FALSE if $result is invalid
     *
     * @see DB_result::free()
     */
    function freeResult($result)
    {
        return is_resource($result) ? mysql_free_result($result) : false;
    }

    // }}}
    // {{{ numCols()

    /**
     * Gets the number of columns in a result set
     *
     * This method is not meant to be called directly.  Use
     * DB_result::numCols() instead.  It can't be declared "protected"
     * because DB_result is a separate object.
     *
     * @param resource $result  PHP's query result resource
     *
     * @return int  the number of columns.  A DB_Error object on failure.
     *
     * @see DB_result::numCols()
     */
    function numCols($result)
    {
        $cols = @mysql_num_fields($result);
        if (!$cols) {
            return $this->mysqlRaiseError();
        }
        return $cols;
    }

    // }}}
    // {{{ numRows()

    /**
     * Gets the number of rows in a result set
     *
     * This method is not meant to be called directly.  Use
     * DB_result::numRows() instead.  It can't be declared "protected"
     * because DB_result is a separate object.
     *
     * @param resource $result  PHP's query result resource
     *
     * @return int  the number of rows.  A DB_Error object on failure.
     *
     * @see DB_result::numRows()
     */
    function numRows($result)
    {
        $rows = @mysql_num_rows($result);
        if ($rows === null) {
            return $this->mysqlRaiseError();
        }
        return $rows;
    }

    // }}}
    // {{{ autoCommit()

    /**
     * Enables or disables automatic commits
     *
     * @param bool $onoff  true turns it on, false turns it off
     *
     * @return int  DB_OK on success.  A DB_Error object if the driver
     *               doesn't support auto-committing transactions.
     */
    function autoCommit($onoff = false)
    {
        // XXX if $this->transaction_opcount > 0, we should probably
        // issue a warning here.
        $this->autocommit = $onoff ? true : false;
        return DB_OK;
    }

    // }}}
    // {{{ commit()

    /**
     * Commits the current transaction
     *
     * @return int  DB_OK on success.  A DB_Error object on failure.
     */
    function commit()
    {
        if ($this->transaction_opcount > 0) {
            if ($this->_db) {
                if (!@mysql_select_db($this->_db, $this->connection)) {
                    return $this->mysqlRaiseError(DB_ERROR_NODBSELECTED);
                }
            }
            $result = @mysql_query('COMMIT', $this->connection);
            $result = @mysql_query('SET AUTOCOMMIT=1', $this->connection);
            $this->transaction_opcount = 0;
            if (!$result) {
                return $this->mysqlRaiseError();
            }
        }
        return DB_OK;
    }

    // }}}
    // {{{ rollback()

    /**
     * Reverts the current transaction
     *
     * @return int  DB_OK on success.  A DB_Error object on failure.
     */
    function rollback()
    {
        if ($this->transaction_opcount > 0) {
            if ($this->_db) {
                if (!@mysql_select_db($this->_db, $this->connection)) {
                    return $this->mysqlRaiseError(DB_ERROR_NODBSELECTED);
                }
            }
            $result = @mysql_query('ROLLBACK', $this->connection);
            $result = @mysql_query('SET AUTOCOMMIT=1', $this->connection);
            $this->transaction_opcount = 0;
            if (!$result) {
                return $this->mysqlRaiseError();
            }
        }
        return DB_OK;
    }

    // }}}
    // {{{ affectedRows()

    /**
     * Determines the number of rows affected by a data maniuplation query
     *
     * 0 is returned for queries that don't manipulate data.
     *
     * @return int  the number of rows.  A DB_Error object on failure.
     */
    function affectedRows()
    {
        if ($this->_last_query_manip) {
            return @mysql_affected_rows($this->connection);
        } else {
            return 0;
        }
     }

    // }}}
    // {{{ nextId()

    /**
     * Returns the next free id in a sequence
     *
     * @param string  $seq_name  name of the sequence
     * @param boolean $ondemand  when true, the seqence is automatically
     *                            created if it does not exist
     *
     * @return int  the next id number in the sequence.
     *               A DB_Error object on failure.
     *
     * @see DB_common::nextID(), DB_common::getSequenceName(),
     *      DB_mysql::createSequence(), DB_mysql::dropSequence()
     */
    function nextId($seq_name, $ondemand = true)
    {
        $seqname = $this->getSequenceName($seq_name);
        do {
            $repeat = 0;
            $this->pushErrorHandling(PEAR_ERROR_RETURN);
            $result = $this->query("UPDATE ${seqname} ".
                                   'SET id=LAST_INSERT_ID(id+1)');
            $this->popErrorHandling();
            if ($result === DB_OK) {
                // COMMON CASE
                $id = @mysql_insert_id($this->connection);
                if ($id != 0) {
                    return $id;
                }
                // EMPTY SEQ TABLE
                // Sequence table must be empty for some reason, so fill
                // it and return 1 and obtain a user-level lock
                $result = $this->getOne("SELECT GET_LOCK('${seqname}_lock',10)");
                if (DB::isError($result)) {
                    return $this->raiseError($result);
                }
                if ($result == 0) {
                    // Failed to get the lock
                    return $this->mysqlRaiseError(DB_ERROR_NOT_LOCKED);
                }

                // add the default value
                $result = $this->query("REPLACE INTO ${seqname} (id) VALUES (0)");
                if (DB::isError($result)) {
                    return $this->raiseError($result);
                }

                // Release the lock
                $result = $this->getOne('SELECT RELEASE_LOCK('
                                        . "'${seqname}_lock')");
                if (DB::isError($result)) {
                    return $this->raiseError($result);
                }
                // We know what the result will be, so no need to try again
                return 1;

            } elseif ($ondemand && DB::isError($result) &&
                $result->getCode() == DB_ERROR_NOSUCHTABLE)
            {
                // ONDEMAND TABLE CREATION
                $result = $this->createSequence($seq_name);
                if (DB::isError($result)) {
                    return $this->raiseError($result);
                } else {
                    $repeat = 1;
                }

            } elseif (DB::isError($result) &&
                      $result->getCode() == DB_ERROR_ALREADY_EXISTS)
            {
                // BACKWARDS COMPAT
                // see _BCsequence() comment
                $result = $this->_BCsequence($seqname);
                if (DB::isError($result)) {
                    return $this->raiseError($result);
                }
                $repeat = 1;
            }
        } while ($repeat);

        return $this->raiseError($result);
    }

    // }}}
    // {{{ createSequence()

    /**
     * Creates a new sequence
     *
     * @param string $seq_name  name of the new sequence
     *
     * @return int  DB_OK on success.  A DB_Error object on failure.
     *
     * @see DB_common::createSequence(), DB_common::getSequenceName(),
     *      DB_mysql::nextID(), DB_mysql::dropSequence()
     */
    function createSequence($seq_name)
    {
        $seqname = $this->getSequenceName($seq_name);
        $res = $this->query('CREATE TABLE ' . $seqname
                            . ' (id INTEGER UNSIGNED AUTO_INCREMENT NOT NULL,'
                            . ' PRIMARY KEY(id))');
        if (DB::isError($res)) {
            return $res;
        }
        // insert yields value 1, nextId call will generate ID 2
        $res = $this->query("INSERT INTO ${seqname} (id) VALUES (0)");
        if (DB::isError($res)) {
            return $res;
        }
        // so reset to zero
        return $this->query("UPDATE ${seqname} SET id = 0");
    }

    // }}}
    // {{{ dropSequence()

    /**
     * Deletes a sequence
     *
     * @param string $seq_name  name of the sequence to be deleted
     *
     * @return int  DB_OK on success.  A DB_Error object on failure.
     *
     * @see DB_common::dropSequence(), DB_common::getSequenceName(),
     *      DB_mysql::nextID(), DB_mysql::createSequence()
     */
    function dropSequence($seq_name)
    {
        return $this->query('DROP TABLE ' . $this->getSequenceName($seq_name));
    }

    // }}}
    // {{{ _BCsequence()

    /**
     * Backwards compatibility with old sequence emulation implementation
     * (clean up the dupes)
     *
     * @param string $seqname  the sequence name to clean up
     *
     * @return bool  true on success.  A DB_Error object on failure.
     *
     * @access private
     */
    function _BCsequence($seqname)
    {
        // Obtain a user-level lock... this will release any previous
        // application locks, but unlike LOCK TABLES, it does not abort
        // the current transaction and is much less frequently used.
        $result = $this->getOne("SELECT GET_LOCK('${seqname}_lock',10)");
        if (DB::isError($result)) {
            return $result;
        }
        if ($result == 0) {
            // Failed to get the lock, can't do the conversion, bail
            // with a DB_ERROR_NOT_LOCKED error
            return $this->mysqlRaiseError(DB_ERROR_NOT_LOCKED);
        }

        $highest_id = $this->getOne("SELECT MAX(id) FROM ${seqname}");
        if (DB::isError($highest_id)) {
            return $highest_id;
        }
        // This should kill all rows except the highest
        // We should probably do something if $highest_id isn't
        // numeric, but I'm at a loss as how to handle that...
        $result = $this->query('DELETE FROM ' . $seqname
                               . " WHERE id <> $highest_id");
        if (DB::isError($result)) {
            return $result;
        }

        // If another thread has been waiting for this lock,
        // it will go thru the above procedure, but will have no
        // real effect
        $result = $this->getOne("SELECT RELEASE_LOCK('${seqname}_lock')");
        if (DB::isError($result)) {
            return $result;
        }
        return true;
    }

    // }}}
    // {{{ quoteIdentifier()

    /**
     * Quotes a string so it can be safely used as a table or column name
     * (WARNING: using names that require this is a REALLY BAD IDEA)
     *
     * WARNING:  Older versions of MySQL can't handle the backtick
     * character (<kbd>`</kbd>) in table or column names.
     *
     * @param string $str  identifier name to be quoted
     *
     * @return string  quoted identifier string
     *
     * @see DB_common::quoteIdentifier()
     * @since Method available since Release 1.6.0
     */
    function quoteIdentifier($str)
    {
        return '`' . str_replace('`', '``', $str) . '`';
    }

    // }}}
    // {{{ escapeSimple()

    /**
     * Escapes a string according to the current DBMS's standards
     *
     * @param string $str  the string to be escaped
     *
     * @return string  the escaped string
     *
     * @see DB_common::quoteSmart()
     * @since Method available since Release 1.6.0
     */
    function escapeSimple($str)
    {
        if (function_exists('mysql_real_escape_string')) {
            return @mysql_real_escape_string($str, $this->connection);
        } else {
            return @mysql_escape_string($str);
        }
    }

    // }}}
    // {{{ modifyQuery()

    /**
     * Changes a query string for various DBMS specific reasons
     *
     * This little hack lets you know how many rows were deleted
     * when running a "DELETE FROM table" query.  Only implemented
     * if the DB_PORTABILITY_DELETE_COUNT portability option is on.
     *
     * @param string $query  the query string to modify
     *
     * @return string  the modified query string
     *
     * @access protected
     * @see DB_common::setOption()
     */
    function modifyQuery($query)
    {
        if ($this->options['portability'] & DB_PORTABILITY_DELETE_COUNT) {
            // "DELETE FROM table" gives 0 affected rows in MySQL.
            // This little hack lets you know how many rows were deleted.
            if (preg_match('/^\s*DELETE\s+FROM\s+(\S+)\s*$/i', $query)) {
                $query = preg_replace('/^\s*DELETE\s+FROM\s+(\S+)\s*$/',
                                      'DELETE FROM \1 WHERE 1=1', $query);
            }
        }
        return $query;
    }

    // }}}
    // {{{ modifyLimitQuery()

    /**
     * Adds LIMIT clauses to a query string according to current DBMS standards
     *
     * @param string $query   the query to modify
     * @param int    $from    the row to start to fetching (0 = the first row)
     * @param int    $count   the numbers of rows to fetch
     * @param mixed  $params  array, string or numeric data to be used in
     *                         execution of the statement.  Quantity of items
     *                         passed must match quantity of placeholders in
     *                         query:  meaning 1 placeholder for non-array
     *                         parameters or 1 placeholder per array element.
     *
     * @return string  the query string with LIMIT clauses added
     *
     * @access protected
     */
    function modifyLimitQuery($query, $from, $count, $params = array())
    {
        if (DB::isManip($query) || $this->_next_query_manip) {
            return $query . " LIMIT $count";
        } else {
            return $query . " LIMIT $from, $count";
        }
    }

    // }}}
    // {{{ mysqlRaiseError()

    /**
     * Produces a DB_Error object regarding the current problem
     *
     * @param int $errno  if the error is being manually raised pass a
     *                     DB_ERROR* constant here.  If this isn't passed
     *                     the error information gathered from the DBMS.
     *
     * @return object  the DB_Error object
     *
     * @see DB_common::raiseError(),
     *      DB_mysql::errorNative(), DB_common::errorCode()
     */
    function mysqlRaiseError($errno = null)
    {
        if ($errno === null) {
            if ($this->options['portability'] & DB_PORTABILITY_ERRORS) {
                $this->errorcode_map[1022] = DB_ERROR_CONSTRAINT;
                $this->errorcode_map[1048] = DB_ERROR_CONSTRAINT_NOT_NULL;
                $this->errorcode_map[1062] = DB_ERROR_CONSTRAINT;
            } else {
                // Doing this in case mode changes during runtime.
                $this->errorcode_map[1022] = DB_ERROR_ALREADY_EXISTS;
                $this->errorcode_map[1048] = DB_ERROR_CONSTRAINT;
                $this->errorcode_map[1062] = DB_ERROR_ALREADY_EXISTS;
            }
            $errno = $this->errorCode(mysql_errno($this->connection));
        }
        return $this->raiseError($errno, null, null, null,
                                 @mysql_errno($this->connection) . ' ** ' .
                                 @mysql_error($this->connection));
    }

    // }}}
    // {{{ errorNative()

    /**
     * Gets the DBMS' native error code produced by the last query
     *
     * @return int  the DBMS' error code
     */
    function errorNative()
    {
        return @mysql_errno($this->connection);
    }

    // }}}
    // {{{ tableInfo()

    /**
     * Returns information about a table or a result set
     *
     * @param object|string  $result  DB_result object from a query or a
     *                                 string containing the name of a table.
     *                                 While this also accepts a query result
     *                                 resource identifier, this behavior is
     *                                 deprecated.
     * @param int            $mode    a valid tableInfo mode
     *
     * @return array  an associative array with the information requested.
     *                 A DB_Error object on failure.
     *
     * @see DB_common::tableInfo()
     */
    function tableInfo($result, $mode = null)
    {
        if (is_string($result)) {
            // Fix for bug #11580.
            if ($this->_db) {
                if (!@mysql_select_db($this->_db, $this->connection)) {
                    return $this->mysqlRaiseError(DB_ERROR_NODBSELECTED);
                }
            }
            
            /*
             * Probably received a table name.
             * Create a result resource identifier.
             */
            $id = @mysql_query("SELECT * FROM $result LIMIT 0",
                               $this->connection);
            $got_string = true;
        } elseif (isset($result->result)) {
            /*
             * Probably received a result object.
             * Extract the result resource identifier.
             */
            $id = $result->result;
            $got_string = false;
        } else {
            /*
             * Probably received a result resource identifier.
             * Copy it.
             * Deprecated.  Here for compatibility only.
             */
            $id = $result;
            $got_string = false;
        }

        if (!is_resource($id)) {
            return $this->mysqlRaiseError(DB_ERROR_NEED_MORE_DATA);
        }

        if ($this->options['portability'] & DB_PORTABILITY_LOWERCASE) {
            $case_func = 'strtolower';
        } else {
            $case_func = 'strval';
        }

        $count = @mysql_num_fields($id);
        $res   = array();

        if ($mode) {
            $res['num_fields'] = $count;
        }

        for ($i = 0; $i < $count; $i++) {
            $res[$i] = array(
                'table' => $case_func(@mysql_field_table($id, $i)),
                'name'  => $case_func(@mysql_field_name($id, $i)),
                'type'  => @mysql_field_type($id, $i),
                'len'   => @mysql_field_len($id, $i),
                'flags' => @mysql_field_flags($id, $i),
            );
            if ($mode & DB_TABLEINFO_ORDER) {
                $res['order'][$res[$i]['name']] = $i;
            }
            if ($mode & DB_TABLEINFO_ORDERTABLE) {
                $res['ordertable'][$res[$i]['table']][$res[$i]['name']] = $i;
            }
        }

        // free the result only if we were called on a table
        if ($got_string) {
            @mysql_free_result($id);
        }
        return $res;
    }

    // }}}
    // {{{ getSpecialQuery()

    /**
     * Obtains the query string needed for listing a given type of objects
     *
     * @param string $type  the kind of objects you want to retrieve
     *
     * @return string  the SQL query string or null if the driver doesn't
     *                  support the object type requested
     *
     * @access protected
     * @see DB_common::getListOf()
     */
    function getSpecialQuery($type)
    {
        switch ($type) {
            case 'tables':
                return 'SHOW TABLES';
            case 'users':
                return 'SELECT DISTINCT User FROM mysql.user';
            case 'databases':
                return 'SHOW DATABASES';
            default:
                return null;
        }
    }

    // }}}

}

/*
 * Local variables:
 * tab-width: 4
 * c-basic-offset: 4
 * End:
 */

?>