/halogy/database/DB_driver.php
PHP | 1366 lines | 698 code | 198 blank | 470 comment | 122 complexity | 90509a270df63b196ce10c1706cf9177 MD5 | raw file
1<?php if ( ! defined('BASEPATH')) exit('No direct script access allowed'); 2/** 3 * CodeIgniter 4 * 5 * An open source application development framework for PHP 4.3.2 or newer 6 * 7 * @package CodeIgniter 8 * @author ExpressionEngine Dev Team 9 * @copyright Copyright (c) 2008 - 2009, EllisLab, Inc. 10 * @license http://codeigniter.com/user_guide/license.html 11 * @link http://codeigniter.com 12 * @since Version 1.0 13 * @filesource 14 */ 15 16// ------------------------------------------------------------------------ 17 18/** 19 * Database Driver Class 20 * 21 * This is the platform-independent base DB implementation class. 22 * This class will not be called directly. Rather, the adapter 23 * class for the specific database will extend and instantiate it. 24 * 25 * @package CodeIgniter 26 * @subpackage Drivers 27 * @category Database 28 * @author ExpressionEngine Dev Team 29 * @link http://codeigniter.com/user_guide/database/ 30 */ 31class CI_DB_driver { 32 33 var $username; 34 var $password; 35 var $hostname; 36 var $database; 37 var $dbdriver = 'mysql'; 38 var $dbprefix = ''; 39 var $char_set = 'utf8'; 40 var $dbcollat = 'utf8_general_ci'; 41 var $autoinit = TRUE; // Whether to automatically initialize the DB 42 var $swap_pre = ''; 43 var $port = ''; 44 var $pconnect = FALSE; 45 var $conn_id = FALSE; 46 var $result_id = FALSE; 47 var $db_debug = FALSE; 48 var $benchmark = 0; 49 var $query_count = 0; 50 var $bind_marker = '?'; 51 var $save_queries = TRUE; 52 var $queries = array(); 53 var $query_times = array(); 54 var $data_cache = array(); 55 var $trans_enabled = TRUE; 56 var $trans_strict = TRUE; 57 var $_trans_depth = 0; 58 var $_trans_status = TRUE; // Used with transactions to determine if a rollback should occur 59 var $cache_on = FALSE; 60 var $cachedir = ''; 61 var $cache_autodel = FALSE; 62 var $CACHE; // The cache class object 63 64 // Private variables 65 var $_protect_identifiers = TRUE; 66 var $_reserved_identifiers = array('*'); // Identifiers that should NOT be escaped 67 68 // These are use with Oracle 69 var $stmt_id; 70 var $curs_id; 71 var $limit_used; 72 73 74 75 /** 76 * Constructor. Accepts one parameter containing the database 77 * connection settings. 78 * 79 * @param array 80 */ 81 function CI_DB_driver($params) 82 { 83 if (is_array($params)) 84 { 85 foreach ($params as $key => $val) 86 { 87 $this->$key = $val; 88 } 89 } 90 91 log_message('debug', 'Database Driver Class Initialized'); 92 } 93 94 // -------------------------------------------------------------------- 95 96 /** 97 * Initialize Database Settings 98 * 99 * @access private Called by the constructor 100 * @param mixed 101 * @return void 102 */ 103 function initialize() 104 { 105 // If an existing connection resource is available 106 // there is no need to connect and select the database 107 if (is_resource($this->conn_id) OR is_object($this->conn_id)) 108 { 109 return TRUE; 110 } 111 112 // ---------------------------------------------------------------- 113 114 // Connect to the database and set the connection ID 115 $this->conn_id = ($this->pconnect == FALSE) ? $this->db_connect() : $this->db_pconnect(); 116 117 // No connection resource? Throw an error 118 if ( ! $this->conn_id) 119 { 120 log_message('error', 'Unable to connect to the database'); 121 122 if ($this->db_debug) 123 { 124 $this->display_error('db_unable_to_connect'); 125 } 126 return FALSE; 127 } 128 129 // ---------------------------------------------------------------- 130 131 // Select the DB... assuming a database name is specified in the config file 132 if ($this->database != '') 133 { 134 if ( ! $this->db_select()) 135 { 136 log_message('error', 'Unable to select database: '.$this->database); 137 138 if ($this->db_debug) 139 { 140 $this->display_error('db_unable_to_select', $this->database); 141 } 142 return FALSE; 143 } 144 else 145 { 146 // We've selected the DB. Now we set the character set 147 if ( ! $this->db_set_charset($this->char_set, $this->dbcollat)) 148 { 149 return FALSE; 150 } 151 152 return TRUE; 153 } 154 } 155 156 return TRUE; 157 } 158 159 // -------------------------------------------------------------------- 160 161 /** 162 * Set client character set 163 * 164 * @access public 165 * @param string 166 * @param string 167 * @return resource 168 */ 169 function db_set_charset($charset, $collation) 170 { 171 if ( ! $this->_db_set_charset($this->char_set, $this->dbcollat)) 172 { 173 log_message('error', 'Unable to set database connection charset: '.$this->char_set); 174 175 if ($this->db_debug) 176 { 177 $this->display_error('db_unable_to_set_charset', $this->char_set); 178 } 179 180 return FALSE; 181 } 182 183 return TRUE; 184 } 185 186 // -------------------------------------------------------------------- 187 188 /** 189 * The name of the platform in use (mysql, mssql, etc...) 190 * 191 * @access public 192 * @return string 193 */ 194 function platform() 195 { 196 return $this->dbdriver; 197 } 198 199 // -------------------------------------------------------------------- 200 201 /** 202 * Database Version Number. Returns a string containing the 203 * version of the database being used 204 * 205 * @access public 206 * @return string 207 */ 208 function version() 209 { 210 if (FALSE === ($sql = $this->_version())) 211 { 212 if ($this->db_debug) 213 { 214 return $this->display_error('db_unsupported_function'); 215 } 216 return FALSE; 217 } 218 219 if ($this->dbdriver == 'oci8') 220 { 221 return $sql; 222 } 223 224 $query = $this->query($sql); 225 return $query->row('ver'); 226 } 227 228 // -------------------------------------------------------------------- 229 230 /** 231 * Execute the query 232 * 233 * Accepts an SQL string as input and returns a result object upon 234 * successful execution of a "read" type query. Returns boolean TRUE 235 * upon successful execution of a "write" type query. Returns boolean 236 * FALSE upon failure, and if the $db_debug variable is set to TRUE 237 * will raise an error. 238 * 239 * @access public 240 * @param string An SQL query string 241 * @param array An array of binding data 242 * @return mixed 243 */ 244 function query($sql, $binds = FALSE, $return_object = TRUE) 245 { 246 if ($sql == '') 247 { 248 if ($this->db_debug) 249 { 250 log_message('error', 'Invalid query: '.$sql); 251 return $this->display_error('db_invalid_query'); 252 } 253 return FALSE; 254 } 255 256 // Verify table prefix and replace if necessary 257 if ( ($this->dbprefix != '' AND $this->swap_pre != '') AND ($this->dbprefix != $this->swap_pre) ) 258 { 259 $sql = preg_replace("/(\W)".$this->swap_pre."(\S+?)/", "\\1".$this->dbprefix."\\2", $sql); 260 } 261 262 // Is query caching enabled? If the query is a "read type" 263 // we will load the caching class and return the previously 264 // cached query if it exists 265 if ($this->cache_on == TRUE AND stristr($sql, 'SELECT')) 266 { 267 if ($this->_cache_init()) 268 { 269 $this->load_rdriver(); 270 if (FALSE !== ($cache = $this->CACHE->read($sql))) 271 { 272 return $cache; 273 } 274 } 275 } 276 277 // Compile binds if needed 278 if ($binds !== FALSE) 279 { 280 $sql = $this->compile_binds($sql, $binds); 281 } 282 283 // Save the query for debugging 284 if ($this->save_queries == TRUE) 285 { 286 $this->queries[] = $sql; 287 } 288 289 // Start the Query Timer 290 $time_start = list($sm, $ss) = explode(' ', microtime()); 291 292 // Run the Query 293 if (FALSE === ($this->result_id = $this->simple_query($sql))) 294 { 295 if ($this->save_queries == TRUE) 296 { 297 $this->query_times[] = 0; 298 } 299 300 // This will trigger a rollback if transactions are being used 301 $this->_trans_status = FALSE; 302 303 if ($this->db_debug) 304 { 305 // grab the error number and message now, as we might run some 306 // additional queries before displaying the error 307 $error_no = $this->_error_number(); 308 $error_msg = $this->_error_message(); 309 310 // We call this function in order to roll-back queries 311 // if transactions are enabled. If we don't call this here 312 // the error message will trigger an exit, causing the 313 // transactions to remain in limbo. 314 $this->trans_complete(); 315 316 // Log and display errors 317 log_message('error', 'Query error: '.$error_msg); 318 return $this->display_error( 319 array( 320 'Error Number: '.$error_no, 321 $error_msg, 322 $sql 323 ) 324 ); 325 } 326 327 return FALSE; 328 } 329 330 // Stop and aggregate the query time results 331 $time_end = list($em, $es) = explode(' ', microtime()); 332 $this->benchmark += ($em + $es) - ($sm + $ss); 333 334 if ($this->save_queries == TRUE) 335 { 336 $this->query_times[] = ($em + $es) - ($sm + $ss); 337 } 338 339 // Increment the query counter 340 $this->query_count++; 341 342 // Was the query a "write" type? 343 // If so we'll simply return true 344 if ($this->is_write_type($sql) === TRUE) 345 { 346 // If caching is enabled we'll auto-cleanup any 347 // existing files related to this particular URI 348 if ($this->cache_on == TRUE AND $this->cache_autodel == TRUE AND $this->_cache_init()) 349 { 350 $this->CACHE->delete(); 351 } 352 353 return TRUE; 354 } 355 356 // Return TRUE if we don't need to create a result object 357 // Currently only the Oracle driver uses this when stored 358 // procedures are used 359 if ($return_object !== TRUE) 360 { 361 return TRUE; 362 } 363 364 // Load and instantiate the result driver 365 366 $driver = $this->load_rdriver(); 367 $RES = new $driver(); 368 $RES->conn_id = $this->conn_id; 369 $RES->result_id = $this->result_id; 370 371 if ($this->dbdriver == 'oci8') 372 { 373 $RES->stmt_id = $this->stmt_id; 374 $RES->curs_id = NULL; 375 $RES->limit_used = $this->limit_used; 376 $this->stmt_id = FALSE; 377 } 378 379 // oci8 vars must be set before calling this 380 $RES->num_rows = $RES->num_rows(); 381 382 // Is query caching enabled? If so, we'll serialize the 383 // result object and save it to a cache file. 384 if ($this->cache_on == TRUE AND $this->_cache_init()) 385 { 386 // We'll create a new instance of the result object 387 // only without the platform specific driver since 388 // we can't use it with cached data (the query result 389 // resource ID won't be any good once we've cached the 390 // result object, so we'll have to compile the data 391 // and save it) 392 $CR = new CI_DB_result(); 393 $CR->num_rows = $RES->num_rows(); 394 $CR->result_object = $RES->result_object(); 395 $CR->result_array = $RES->result_array(); 396 397 // Reset these since cached objects can not utilize resource IDs. 398 $CR->conn_id = NULL; 399 $CR->result_id = NULL; 400 401 $this->CACHE->write($sql, $CR); 402 } 403 404 return $RES; 405 } 406 407 // -------------------------------------------------------------------- 408 409 /** 410 * Load the result drivers 411 * 412 * @access public 413 * @return string the name of the result class 414 */ 415 function load_rdriver() 416 { 417 $driver = 'CI_DB_'.$this->dbdriver.'_result'; 418 419 if ( ! class_exists($driver)) 420 { 421 include_once(BASEPATH.'database/DB_result'.EXT); 422 include_once(BASEPATH.'database/drivers/'.$this->dbdriver.'/'.$this->dbdriver.'_result'.EXT); 423 } 424 425 return $driver; 426 } 427 428 // -------------------------------------------------------------------- 429 430 /** 431 * Simple Query 432 * This is a simplified version of the query() function. Internally 433 * we only use it when running transaction commands since they do 434 * not require all the features of the main query() function. 435 * 436 * @access public 437 * @param string the sql query 438 * @return mixed 439 */ 440 function simple_query($sql) 441 { 442 if ( ! $this->conn_id) 443 { 444 $this->initialize(); 445 } 446 447 return $this->_execute($sql); 448 } 449 450 // -------------------------------------------------------------------- 451 452 /** 453 * Disable Transactions 454 * This permits transactions to be disabled at run-time. 455 * 456 * @access public 457 * @return void 458 */ 459 function trans_off() 460 { 461 $this->trans_enabled = FALSE; 462 } 463 464 // -------------------------------------------------------------------- 465 466 /** 467 * Enable/disable Transaction Strict Mode 468 * When strict mode is enabled, if you are running multiple groups of 469 * transactions, if one group fails all groups will be rolled back. 470 * If strict mode is disabled, each group is treated autonomously, meaning 471 * a failure of one group will not affect any others 472 * 473 * @access public 474 * @return void 475 */ 476 function trans_strict($mode = TRUE) 477 { 478 $this->trans_strict = is_bool($mode) ? $mode : TRUE; 479 } 480 481 // -------------------------------------------------------------------- 482 483 /** 484 * Start Transaction 485 * 486 * @access public 487 * @return void 488 */ 489 function trans_start($test_mode = FALSE) 490 { 491 if ( ! $this->trans_enabled) 492 { 493 return FALSE; 494 } 495 496 // When transactions are nested we only begin/commit/rollback the outermost ones 497 if ($this->_trans_depth > 0) 498 { 499 $this->_trans_depth += 1; 500 return; 501 } 502 503 $this->trans_begin($test_mode); 504 } 505 506 // -------------------------------------------------------------------- 507 508 /** 509 * Complete Transaction 510 * 511 * @access public 512 * @return bool 513 */ 514 function trans_complete() 515 { 516 if ( ! $this->trans_enabled) 517 { 518 return FALSE; 519 } 520 521 // When transactions are nested we only begin/commit/rollback the outermost ones 522 if ($this->_trans_depth > 1) 523 { 524 $this->_trans_depth -= 1; 525 return TRUE; 526 } 527 528 // The query() function will set this flag to FALSE in the event that a query failed 529 if ($this->_trans_status === FALSE) 530 { 531 $this->trans_rollback(); 532 533 // If we are NOT running in strict mode, we will reset 534 // the _trans_status flag so that subsequent groups of transactions 535 // will be permitted. 536 if ($this->trans_strict === FALSE) 537 { 538 $this->_trans_status = TRUE; 539 } 540 541 log_message('debug', 'DB Transaction Failure'); 542 return FALSE; 543 } 544 545 $this->trans_commit(); 546 return TRUE; 547 } 548 549 // -------------------------------------------------------------------- 550 551 /** 552 * Lets you retrieve the transaction flag to determine if it has failed 553 * 554 * @access public 555 * @return bool 556 */ 557 function trans_status() 558 { 559 return $this->_trans_status; 560 } 561 562 // -------------------------------------------------------------------- 563 564 /** 565 * Compile Bindings 566 * 567 * @access public 568 * @param string the sql statement 569 * @param array an array of bind data 570 * @return string 571 */ 572 function compile_binds($sql, $binds) 573 { 574 if (strpos($sql, $this->bind_marker) === FALSE) 575 { 576 return $sql; 577 } 578 579 if ( ! is_array($binds)) 580 { 581 $binds = array($binds); 582 } 583 584 // Get the sql segments around the bind markers 585 $segments = explode($this->bind_marker, $sql); 586 587 // The count of bind should be 1 less then the count of segments 588 // If there are more bind arguments trim it down 589 if (count($binds) >= count($segments)) { 590 $binds = array_slice($binds, 0, count($segments)-1); 591 } 592 593 // Construct the binded query 594 $result = $segments[0]; 595 $i = 0; 596 foreach ($binds as $bind) 597 { 598 $result .= $this->escape($bind); 599 $result .= $segments[++$i]; 600 } 601 602 return $result; 603 } 604 605 // -------------------------------------------------------------------- 606 607 /** 608 * Determines if a query is a "write" type. 609 * 610 * @access public 611 * @param string An SQL query string 612 * @return boolean 613 */ 614 function is_write_type($sql) 615 { 616 if ( ! preg_match('/^\s*"?(SET|INSERT|UPDATE|DELETE|REPLACE|CREATE|DROP|TRUNCATE|LOAD DATA|COPY|ALTER|GRANT|REVOKE|LOCK|UNLOCK)\s+/i', $sql)) 617 { 618 return FALSE; 619 } 620 return TRUE; 621 } 622 623 // -------------------------------------------------------------------- 624 625 /** 626 * Calculate the aggregate query elapsed time 627 * 628 * @access public 629 * @param integer The number of decimal places 630 * @return integer 631 */ 632 function elapsed_time($decimals = 6) 633 { 634 return number_format($this->benchmark, $decimals); 635 } 636 637 // -------------------------------------------------------------------- 638 639 /** 640 * Returns the total number of queries 641 * 642 * @access public 643 * @return integer 644 */ 645 function total_queries() 646 { 647 return $this->query_count; 648 } 649 650 // -------------------------------------------------------------------- 651 652 /** 653 * Returns the last query that was executed 654 * 655 * @access public 656 * @return void 657 */ 658 function last_query() 659 { 660 return end($this->queries); 661 } 662 663 // -------------------------------------------------------------------- 664 665 /** 666 * "Smart" Escape String 667 * 668 * Escapes data based on type 669 * Sets boolean and null types 670 * 671 * @access public 672 * @param string 673 * @return mixed 674 */ 675 function escape($str) 676 { 677 if (is_string($str)) 678 { 679 $str = "'".$this->escape_str($str)."'"; 680 } 681 elseif (is_bool($str)) 682 { 683 $str = ($str === FALSE) ? 0 : 1; 684 } 685 elseif (is_null($str)) 686 { 687 $str = 'NULL'; 688 } 689 690 return $str; 691 } 692 693 // -------------------------------------------------------------------- 694 695 /** 696 * Escape LIKE String 697 * 698 * Calls the individual driver for platform 699 * specific escaping for LIKE conditions 700 * 701 * @access public 702 * @param string 703 * @return mixed 704 */ 705 function escape_like_str($str) 706 { 707 return $this->escape_str($str, TRUE); 708 } 709 710 // -------------------------------------------------------------------- 711 712 /** 713 * Primary 714 * 715 * Retrieves the primary key. It assumes that the row in the first 716 * position is the primary key 717 * 718 * @access public 719 * @param string the table name 720 * @return string 721 */ 722 function primary($table = '') 723 { 724 $fields = $this->list_fields($table); 725 726 if ( ! is_array($fields)) 727 { 728 return FALSE; 729 } 730 731 return current($fields); 732 } 733 734 // -------------------------------------------------------------------- 735 736 /** 737 * Returns an array of table names 738 * 739 * @access public 740 * @return array 741 */ 742 function list_tables($constrain_by_prefix = FALSE) 743 { 744 // Is there a cached result? 745 if (isset($this->data_cache['table_names'])) 746 { 747 return $this->data_cache['table_names']; 748 } 749 750 if (FALSE === ($sql = $this->_list_tables($constrain_by_prefix))) 751 { 752 if ($this->db_debug) 753 { 754 return $this->display_error('db_unsupported_function'); 755 } 756 return FALSE; 757 } 758 759 $retval = array(); 760 $query = $this->query($sql); 761 762 if ($query->num_rows() > 0) 763 { 764 foreach($query->result_array() as $row) 765 { 766 if (isset($row['TABLE_NAME'])) 767 { 768 $retval[] = $row['TABLE_NAME']; 769 } 770 else 771 { 772 $retval[] = array_shift($row); 773 } 774 } 775 } 776 777 $this->data_cache['table_names'] = $retval; 778 return $this->data_cache['table_names']; 779 } 780 781 // -------------------------------------------------------------------- 782 783 /** 784 * Determine if a particular table exists 785 * @access public 786 * @return boolean 787 */ 788 function table_exists($table_name) 789 { 790 return ( ! in_array($this->_protect_identifiers($table_name, TRUE, FALSE, FALSE), $this->list_tables())) ? FALSE : TRUE; 791 } 792 793 // -------------------------------------------------------------------- 794 795 /** 796 * Fetch MySQL Field Names 797 * 798 * @access public 799 * @param string the table name 800 * @return array 801 */ 802 function list_fields($table = '') 803 { 804 // Is there a cached result? 805 if (isset($this->data_cache['field_names'][$table])) 806 { 807 return $this->data_cache['field_names'][$table]; 808 } 809 810 if ($table == '') 811 { 812 if ($this->db_debug) 813 { 814 return $this->display_error('db_field_param_missing'); 815 } 816 return FALSE; 817 } 818 819 if (FALSE === ($sql = $this->_list_columns($this->_protect_identifiers($table, TRUE, NULL, FALSE)))) 820 { 821 if ($this->db_debug) 822 { 823 return $this->display_error('db_unsupported_function'); 824 } 825 return FALSE; 826 } 827 828 $query = $this->query($sql); 829 830 $retval = array(); 831 foreach($query->result_array() as $row) 832 { 833 if (isset($row['COLUMN_NAME'])) 834 { 835 $retval[] = $row['COLUMN_NAME']; 836 } 837 else 838 { 839 $retval[] = current($row); 840 } 841 } 842 843 $this->data_cache['field_names'][$table] = $retval; 844 return $this->data_cache['field_names'][$table]; 845 } 846 847 // -------------------------------------------------------------------- 848 849 /** 850 * Determine if a particular field exists 851 * @access public 852 * @param string 853 * @param string 854 * @return boolean 855 */ 856 function field_exists($field_name, $table_name) 857 { 858 return ( ! in_array($field_name, $this->list_fields($table_name))) ? FALSE : TRUE; 859 } 860 861 // -------------------------------------------------------------------- 862 863 /** 864 * Returns an object with field data 865 * 866 * @access public 867 * @param string the table name 868 * @return object 869 */ 870 function field_data($table = '') 871 { 872 if ($table == '') 873 { 874 if ($this->db_debug) 875 { 876 return $this->display_error('db_field_param_missing'); 877 } 878 return FALSE; 879 } 880 881 $query = $this->query($this->_field_data($this->_protect_identifiers($table, TRUE, NULL, FALSE))); 882 883 return $query->field_data(); 884 } 885 886 // -------------------------------------------------------------------- 887 888 /** 889 * Generate an insert string 890 * 891 * @access public 892 * @param string the table upon which the query will be performed 893 * @param array an associative array data of key/values 894 * @return string 895 */ 896 function insert_string($table, $data) 897 { 898 $fields = array(); 899 $values = array(); 900 901 foreach($data as $key => $val) 902 { 903 $fields[] = $this->_escape_identifiers($key); 904 $values[] = $this->escape($val); 905 } 906 907 return $this->_insert($this->_protect_identifiers($table, TRUE, NULL, FALSE), $fields, $values); 908 } 909 910 // -------------------------------------------------------------------- 911 912 /** 913 * Generate an update string 914 * 915 * @access public 916 * @param string the table upon which the query will be performed 917 * @param array an associative array data of key/values 918 * @param mixed the "where" statement 919 * @return string 920 */ 921 function update_string($table, $data, $where) 922 { 923 if ($where == '') 924 { 925 return false; 926 } 927 928 $fields = array(); 929 foreach($data as $key => $val) 930 { 931 $fields[$this->_protect_identifiers($key)] = $this->escape($val); 932 } 933 934 if ( ! is_array($where)) 935 { 936 $dest = array($where); 937 } 938 else 939 { 940 $dest = array(); 941 foreach ($where as $key => $val) 942 { 943 $prefix = (count($dest) == 0) ? '' : ' AND '; 944 945 if ($val !== '') 946 { 947 if ( ! $this->_has_operator($key)) 948 { 949 $key .= ' ='; 950 } 951 952 $val = ' '.$this->escape($val); 953 } 954 955 $dest[] = $prefix.$key.$val; 956 } 957 } 958 959 return $this->_update($this->_protect_identifiers($table, TRUE, NULL, FALSE), $fields, $dest); 960 } 961 962 // -------------------------------------------------------------------- 963 964 /** 965 * Tests whether the string has an SQL operator 966 * 967 * @access private 968 * @param string 969 * @return bool 970 */ 971 function _has_operator($str) 972 { 973 $str = trim($str); 974 if ( ! preg_match("/(\s|<|>|!|=|is null|is not null)/i", $str)) 975 { 976 return FALSE; 977 } 978 979 return TRUE; 980 } 981 982 // -------------------------------------------------------------------- 983 984 /** 985 * Enables a native PHP function to be run, using a platform agnostic wrapper. 986 * 987 * @access public 988 * @param string the function name 989 * @param mixed any parameters needed by the function 990 * @return mixed 991 */ 992 function call_function($function) 993 { 994 $driver = ($this->dbdriver == 'postgre') ? 'pg_' : $this->dbdriver.'_'; 995 996 if (FALSE === strpos($driver, $function)) 997 { 998 $function = $driver.$function; 999 } 1000 1001 if ( ! function_exists($function)) 1002 { 1003 if ($this->db_debug) 1004 { 1005 return $this->display_error('db_unsupported_function'); 1006 } 1007 return FALSE; 1008 } 1009 else 1010 { 1011 $args = (func_num_args() > 1) ? array_splice(func_get_args(), 1) : null; 1012 1013 return call_user_func_array($function, $args); 1014 } 1015 } 1016 1017 // -------------------------------------------------------------------- 1018 1019 /** 1020 * Set Cache Directory Path 1021 * 1022 * @access public 1023 * @param string the path to the cache directory 1024 * @return void 1025 */ 1026 function cache_set_path($path = '') 1027 { 1028 $this->cachedir = $path; 1029 } 1030 1031 // -------------------------------------------------------------------- 1032 1033 /** 1034 * Enable Query Caching 1035 * 1036 * @access public 1037 * @return void 1038 */ 1039 function cache_on() 1040 { 1041 $this->cache_on = TRUE; 1042 return TRUE; 1043 } 1044 1045 // -------------------------------------------------------------------- 1046 1047 /** 1048 * Disable Query Caching 1049 * 1050 * @access public 1051 * @return void 1052 */ 1053 function cache_off() 1054 { 1055 $this->cache_on = FALSE; 1056 return FALSE; 1057 } 1058 1059 1060 // -------------------------------------------------------------------- 1061 1062 /** 1063 * Delete the cache files associated with a particular URI 1064 * 1065 * @access public 1066 * @return void 1067 */ 1068 function cache_delete($segment_one = '', $segment_two = '') 1069 { 1070 if ( ! $this->_cache_init()) 1071 { 1072 return FALSE; 1073 } 1074 return $this->CACHE->delete($segment_one, $segment_two); 1075 } 1076 1077 // -------------------------------------------------------------------- 1078 1079 /** 1080 * Delete All cache files 1081 * 1082 * @access public 1083 * @return void 1084 */ 1085 function cache_delete_all() 1086 { 1087 if ( ! $this->_cache_init()) 1088 { 1089 return FALSE; 1090 } 1091 1092 return $this->CACHE->delete_all(); 1093 } 1094 1095 // -------------------------------------------------------------------- 1096 1097 /** 1098 * Initialize the Cache Class 1099 * 1100 * @access private 1101 * @return void 1102 */ 1103 function _cache_init() 1104 { 1105 if (is_object($this->CACHE) AND class_exists('CI_DB_Cache')) 1106 { 1107 return TRUE; 1108 } 1109 1110 if ( ! class_exists('CI_DB_Cache')) 1111 { 1112 if ( ! @include(BASEPATH.'database/DB_cache'.EXT)) 1113 { 1114 return $this->cache_off(); 1115 } 1116 } 1117 1118 $this->CACHE = new CI_DB_Cache($this); // pass db object to support multiple db connections and returned db objects 1119 return TRUE; 1120 } 1121 1122 // -------------------------------------------------------------------- 1123 1124 /** 1125 * Close DB Connection 1126 * 1127 * @access public 1128 * @return void 1129 */ 1130 function close() 1131 { 1132 if (is_resource($this->conn_id) OR is_object($this->conn_id)) 1133 { 1134 $this->_close($this->conn_id); 1135 } 1136 $this->conn_id = FALSE; 1137 } 1138 1139 // -------------------------------------------------------------------- 1140 1141 /** 1142 * Display an error message 1143 * 1144 * @access public 1145 * @param string the error message 1146 * @param string any "swap" values 1147 * @param boolean whether to localize the message 1148 * @return string sends the application/error_db.php template 1149 */ 1150 function display_error($error = '', $swap = '', $native = FALSE) 1151 { 1152 $LANG =& load_class('Language'); 1153 $LANG->load('db'); 1154 1155 $heading = $LANG->line('db_error_heading'); 1156 1157 if ($native == TRUE) 1158 { 1159 $message = $error; 1160 } 1161 else 1162 { 1163 $message = ( ! is_array($error)) ? array(str_replace('%s', $swap, $LANG->line($error))) : $error; 1164 } 1165 1166 $error =& load_class('Exceptions'); 1167 echo $error->show_error($heading, $message, 'error_db'); 1168 exit; 1169 } 1170 1171 // -------------------------------------------------------------------- 1172 1173 /** 1174 * Protect Identifiers 1175 * 1176 * This function adds backticks if appropriate based on db type 1177 * 1178 * @access private 1179 * @param mixed the item to escape 1180 * @return mixed the item with backticks 1181 */ 1182 function protect_identifiers($item, $prefix_single = FALSE) 1183 { 1184 return $this->_protect_identifiers($item, $prefix_single); 1185 } 1186 1187 // -------------------------------------------------------------------- 1188 1189 /** 1190 * Protect Identifiers 1191 * 1192 * This function is used extensively by the Active Record class, and by 1193 * a couple functions in this class. 1194 * It takes a column or table name (optionally with an alias) and inserts 1195 * the table prefix onto it. Some logic is necessary in order to deal with 1196 * column names that include the path. Consider a query like this: 1197 * 1198 * SELECT * FROM hostname.database.table.column AS c FROM hostname.database.table 1199 * 1200 * Or a query with aliasing: 1201 * 1202 * SELECT m.member_id, m.member_name FROM members AS m 1203 * 1204 * Since the column name can include up to four segments (host, DB, table, column) 1205 * or also have an alias prefix, we need to do a bit of work to figure this out and 1206 * insert the table prefix (if it exists) in the proper position, and escape only 1207 * the correct identifiers. 1208 * 1209 * @access private 1210 * @param string 1211 * @param bool 1212 * @param mixed 1213 * @param bool 1214 * @return string 1215 */ 1216 function _protect_identifiers($item, $prefix_single = FALSE, $protect_identifiers = NULL, $field_exists = TRUE) 1217 { 1218 if ( ! is_bool($protect_identifiers)) 1219 { 1220 $protect_identifiers = $this->_protect_identifiers; 1221 } 1222 1223 if (is_array($item)) 1224 { 1225 $escaped_array = array(); 1226 1227 foreach($item as $k => $v) 1228 { 1229 $escaped_array[$this->_protect_identifiers($k)] = $this->_protect_identifiers($v); 1230 } 1231 1232 return $escaped_array; 1233 } 1234 1235 // Convert tabs or multiple spaces into single spaces 1236 $item = preg_replace('/[\t ]+/', ' ', $item); 1237 1238 // If the item has an alias declaration we remove it and set it aside. 1239 // Basically we remove everything to the right of the first space 1240 $alias = ''; 1241 if (strpos($item, ' ') !== FALSE) 1242 { 1243 $alias = strstr($item, " "); 1244 $item = substr($item, 0, - strlen($alias)); 1245 } 1246 1247 // This is basically a bug fix for queries that use MAX, MIN, etc. 1248 // If a parenthesis is found we know that we do not need to 1249 // escape the data or add a prefix. There's probably a more graceful 1250 // way to deal with this, but I'm not thinking of it -- Rick 1251 if (strpos($item, '(') !== FALSE) 1252 { 1253 return $item.$alias; 1254 } 1255 1256 // Break the string apart if it contains periods, then insert the table prefix 1257 // in the correct location, assuming the period doesn't indicate that we're dealing 1258 // with an alias. While we're at it, we will escape the components 1259 if (strpos($item, '.') !== FALSE) 1260 { 1261 $parts = explode('.', $item); 1262 1263 // Does the first segment of the exploded item match 1264 // one of the aliases previously identified? If so, 1265 // we have nothing more to do other than escape the item 1266 if (in_array($parts[0], $this->ar_aliased_tables)) 1267 { 1268 if ($protect_identifiers === TRUE) 1269 { 1270 foreach ($parts as $key => $val) 1271 { 1272 if ( ! in_array($val, $this->_reserved_identifiers)) 1273 { 1274 $parts[$key] = $this->_escape_identifiers($val); 1275 } 1276 } 1277 1278 $item = implode('.', $parts); 1279 } 1280 return $item.$alias; 1281 } 1282 1283 // Is there a table prefix defined in the config file? If not, no need to do anything 1284 if ($this->dbprefix != '') 1285 { 1286 // We now add the table prefix based on some logic. 1287 // Do we have 4 segments (hostname.database.table.column)? 1288 // If so, we add the table prefix to the column name in the 3rd segment. 1289 if (isset($parts[3])) 1290 { 1291 $i = 2; 1292 } 1293 // Do we have 3 segments (database.table.column)? 1294 // If so, we add the table prefix to the column name in 2nd position 1295 elseif (isset($parts[2])) 1296 { 1297 $i = 1; 1298 } 1299 // Do we have 2 segments (table.column)? 1300 // If so, we add the table prefix to the column name in 1st segment 1301 else 1302 { 1303 $i = 0; 1304 } 1305 1306 // This flag is set when the supplied $item does not contain a field name. 1307 // This can happen when this function is being called from a JOIN. 1308 if ($field_exists == FALSE) 1309 { 1310 $i++; 1311 } 1312 1313 // Verify table prefix and replace if necessary 1314 if ($this->swap_pre != '' && strncmp($parts[$i], $this->swap_pre, strlen($this->swap_pre)) === 0) 1315 { 1316 $parts[$i] = preg_replace("/^".$this->swap_pre."(\S+?)/", $this->dbprefix."\\1", $parts[$i]); 1317 } 1318 1319 // We only add the table prefix if it does not already exist 1320 if (substr($parts[$i], 0, strlen($this->dbprefix)) != $this->dbprefix) 1321 { 1322 $parts[$i] = $this->dbprefix.$parts[$i]; 1323 } 1324 1325 // Put the parts back together 1326 $item = implode('.', $parts); 1327 } 1328 1329 if ($protect_identifiers === TRUE) 1330 { 1331 $item = $this->_escape_identifiers($item); 1332 } 1333 1334 return $item.$alias; 1335 } 1336 1337 // Is there a table prefix? If not, no need to insert it 1338 if ($this->dbprefix != '') 1339 { 1340 // Verify table prefix and replace if necessary 1341 if ($this->swap_pre != '' && strncmp($item, $this->swap_pre, strlen($this->swap_pre)) === 0) 1342 { 1343 $item = preg_replace("/^".$this->swap_pre."(\S+?)/", $this->dbprefix."\\1", $item); 1344 } 1345 1346 // Do we prefix an item with no segments? 1347 if ($prefix_single == TRUE AND substr($item, 0, strlen($this->dbprefix)) != $this->dbprefix) 1348 { 1349 $item = $this->dbprefix.$item; 1350 } 1351 } 1352 1353 if ($protect_identifiers === TRUE AND ! in_array($item, $this->_reserved_identifiers)) 1354 { 1355 $item = $this->_escape_identifiers($item); 1356 } 1357 1358 return $item.$alias; 1359 } 1360 1361 1362} 1363 1364 1365/* End of file DB_driver.php */ 1366/* Location: ./system/database/DB_driver.php */