db-module.php

<?php
/**
 * WordPress DB Class
 *
 * Original code from {@link http://www.poradnik-webmastera.com/ Daniel Fruzynski (daniel@poradnik-webmastera.com)}
 * Original code from {@link http://php.justinvincent.com Justin Vincent (justin@visunet.ie)}
 *
 * @package WordPress
 * @subpackage Database
 * @since 0.71
 */

/**
 * WordPress Database Access Abstraction Object
 *
 * It is possible to replace this class with your own
 * by setting the $wpdb global variable in wp-content/db.php
 * file with your class. You can name it wpdb also, since
 * this file will not be included, if the other file is
 * available.
 *
 * @link http://codex.wordpress.org/Function_Reference/wpdb_Class
 *
 * @package WordPress
 * @subpackage Database
 * @since 0.71
 * @final
 */
if ( ! class_exists( 'dbrc_wpdb' ) ) {
	class dbrc_wpdb extends wpdb {

		// --- DB Cache Start ---
		/**
		 * Amount of all queries cached by DB Cache Reloaded made
		 *
		 * @var int
		 */
		var $num_cachequeries = 0;
		/**
		 * Amount of DML queries
		 *
		 * @var int
		 */
		var $dbcr_num_dml_queries = 0;
		/**
		 * True if caching is active, otherwise false
		 *
		 * @var bool
		 */
		var $dbcr_cacheable = true;
		/**
		 * Array with DB Cache Reloaded config
		 *
		 * @var array
		 */
		var $dbcr_config = null;
		/**
		 * DB Cache Reloaded helper
		 *
		 * @var object of pcache
		 */
		var $dbcr_cache = null;
		/**
		 * True if DB Cache Reloaded should show error in admin section
		 *
		 * @var bool
		 */
		var $dbcr_show_error = false;
		/**
		 * DB Cache Reloaded DB module version
		 *
		 * @var int
		 */
		var $dbcr_version = DBCR_DB_MODULE_VER;
		// --- DB Cache End ---

		/**
		 * Connects to the database server and selects a database
		 *
		 * PHP4 compatibility layer for calling the PHP5 constructor.
		 *
		 * @uses wpdb::__construct() Passes parameters and returns result
		 * @since 0.71
		 *
		 * @param string $dbuser MySQL database user
		 * @param string $dbpassword MySQL database password
		 * @param string $dbname MySQL database name
		 * @param string $dbhost MySQL database host
		 */
		function wpdb( $dbuser, $dbpassword, $dbname, $dbhost ) {
			if ( defined( 'WP_USE_MULTIPLE_DB' ) && WP_USE_MULTIPLE_DB ) {
				$this->db_connect();
			}

			return $this->__construct( $dbuser, $dbpassword, $dbname, $dbhost );
		}

		/**
		 * Connects to the database server and selects a database
		 *
		 * PHP5 style constructor for compatibility with PHP5. Does
		 * the actual setting up of the class properties and connection
		 * to the database.
		 *
		 * @link http://core.trac.wordpress.org/ticket/3354
		 * @since 2.0.8
		 *
		 * @param string $dbuser MySQL database user
		 * @param string $dbpassword MySQL database password
		 * @param string $dbname MySQL database name
		 * @param string $dbhost MySQL database host
		 */
		function __construct( $dbuser, $dbpassword, $dbname, $dbhost ) {
			register_shutdown_function( array( $this, '__destruct' ) );

			if ( WP_DEBUG ) {
				$this->show_errors();
			}

			$this->init_charset();

			$this->dbuser     = $dbuser;
			$this->dbpassword = $dbpassword;
			$this->dbname     = $dbname;
			$this->dbhost     = $dbhost;

			$this->db_connect();

			// --- DB Cache Start ---
			// Caching
			// require_once would be better, but some people deletes plugin without deactivating it first
			if ( @include_once( DBCR_PATH . '/db-functions.php' ) ) {
				$this->dbcr_config          = unserialize( @file_get_contents( WP_CONTENT_DIR . '/db-config.ini' ) );
				$this->dbcr_config['debug'] = false; //TODO: put this into option page
				$this->dbcr_cache           = new pcache();
				$this->dbcr_cache->lifetime = isset( $this->dbcr_config['timeout'] ) ? $this->dbcr_config['timeout'] : 1800;
				$this->dbcr_cache->lifetime *= 60; //convert to seconds

				// cache only frontside
				if (
					( defined( 'WP_ADMIN' ) && WP_ADMIN ) ||
					( defined( 'DOING_CRON' ) && DOING_CRON ) ||
					( defined( 'DOING_AJAX' ) && DOING_AJAX ) ||
					strpos( $_SERVER['REQUEST_URI'], 'wp-admin' ) ||
					strpos( $_SERVER['REQUEST_URI'], 'wp-login' ) ||
					strpos( $_SERVER['REQUEST_URI'], 'wp-register' ) ||
					strpos( $_SERVER['REQUEST_URI'], 'wp-signup' )
				) {
					$this->dbcr_cacheable = false;
				}
			} else { // Cannot include db-functions.php
				$this->dbcr_cacheable  = false;
				$this->dbcr_show_error = true;
			}
			// --- DB Cache End ---
		}

		/**
		 * PHP5 style destructor and will run when database object is destroyed.
		 *
		 * @see wpdb::__construct()
		 * @since 2.0.8
		 * @return bool true
		 */
		function __destruct() {
			return true;
		}

		/**
		 * Perform a MySQL database query, using current database connection.
		 *
		 * More information can be found on the codex page.
		 *
		 * @since 0.71
		 *
		 * @param string $query Database query
		 *
		 * @return int|false Number of rows affected/selected or false on error
		 */
		function query( $query ) {
			return $this->dbcr_query( $query, true );
		}

		function dbcr_query( $query, $maybe_cache = true ) {
			if ( ! $this->ready ) {
				return false;
			}

			// some queries are made before the plugins have been loaded, and thus cannot be filtered with this method
			if ( function_exists( 'apply_filters' ) ) {
				$query = apply_filters( 'query', $query );
			}

			$return_val = 0;
			$this->flush();

			// Log how the function was called
			$this->func_call = "\$db->query(\"$query\")";

			// Keep track of the last query for debug..
			$this->last_query = $query;

			// Perform the query via std mysql_query function..
			if ( ( defined( 'SAVEQUERIES' ) && SAVEQUERIES ) || ( defined( 'DBCR_SAVEQUERIES' ) && DBCR_SAVEQUERIES ) ) {
				$this->timer_start();
			}

			// --- DB Cache Start ---
			$dbcr_db = 'local';
			// --- DB Cache End ---

			// use $this->dbh for read ops, and $this->dbhwrite for write ops
			// use $this->dbhglobal for gloal table ops
			unset( $dbh );
			if ( defined( 'WP_USE_MULTIPLE_DB' ) && WP_USE_MULTIPLE_DB ) {
				if ( $this->blogs != '' && preg_match( "/(" . $this->blogs . "|" . $this->users . "|" . $this->usermeta . "|" . $this->site . "|" . $this->sitemeta . "|" . $this->sitecategories . ")/i", $query ) ) {
					if ( false == isset( $this->dbhglobal ) ) {
						$this->db_connect( $query );
					}
					$dbh                = $this->dbhglobal;
					$this->last_db_used = "global";
					// --- DB Cache Start ---
					$dbcr_db = 'global';
					// --- DB Cache End ---
				} elseif ( preg_match( "/^\\s*(alter table|create|insert|delete|update|replace) /i", $query ) ) {
					if ( false == isset( $this->dbhwrite ) ) {
						$this->db_connect( $query );
					}
					$dbh                = $this->dbhwrite;
					$this->last_db_used = "write";
				} else {
					$dbh                = $this->dbh;
					$this->last_db_used = "read";
				}
			} else {
				$dbh                = $this->dbh;
				$this->last_db_used = "other/read";
				// DB Cache Start
				if ( $this->blogs != '' && preg_match( "/(" . $this->blogs . "|" . $this->users . "|" . $this->usermeta . "|" . $this->site . "|" . $this->sitemeta . "|" . $this->sitecategories . ")/i", $query ) ) {
					$dbcr_db = 'global';
				}
				// DB Cache End
			}

			// Caching
			$dbcr_cacheable = false;
			// check if pcache object is in place
			if ( ! is_null( $this->dbcr_cache ) ) {
				$dbcr_cacheable = $this->dbcr_cacheable && $maybe_cache;

				if ( $dbcr_cacheable ) {
					// do not cache non-select queries
					if ( preg_match( "/\\s*(insert|delete|update|replace|alter|SET NAMES|FOUND_ROWS|RAND)\\b/si", $query ) ) {
						$dbcr_cacheable = false;
					} elseif ( // For hard queries - skip them
						//preg_match(  "/\\s*(JOIN)/si", $query ) ||
						// User-defined cache filters
					( isset( $this->dbcr_config['filter'] ) && ( $this->dbcr_config['filter'] != '' ) &&
					  preg_match( "/\\s*(" . $this->dbcr_config['filter'] . ")/si", $query ) ) ) {
						$dbcr_cacheable = false;
					}
				}

				if ( $dbcr_cacheable ) {
					$dbcr_queryid = md5( $query );

					if ( strpos( $query, '_options' ) ) {
						$this->dbcr_cache->set_storage( $dbcr_db, 'options' );
					} elseif ( strpos( $query, '_links' ) ) {
						$this->dbcr_cache->set_storage( $dbcr_db, 'links' );
					} elseif ( strpos( $query, '_terms' ) ) {
						$this->dbcr_cache->set_storage( $dbcr_db, 'terms' );
					} elseif ( strpos( $query, '_user' ) ) {
						$this->dbcr_cache->set_storage( $dbcr_db, 'users' );
					} elseif ( strpos( $query, '_post' ) ) {
						$this->dbcr_cache->set_storage( $dbcr_db, 'posts' );
					} elseif ( strpos( $query, 'JOIN' ) ) {
						$this->dbcr_cache->set_storage( $dbcr_db, 'joins' );
					} else {
						$this->dbcr_cache->set_storage( $dbcr_db, '' );
					}
				}

				/* Debug part */
				if ( isset( $this->dbcr_config['debug'] ) && $this->dbcr_config['debug'] ) {
					if ( $dbcr_cacheable ) {
						echo "\n<!-- cache: $query -->\n\n";
					} else {
						echo "\n<!-- mysql: $query -->\n\n";
					}
				}
			} elseif ( $this->dbcr_show_error ) {
				$this->dbcr_show_error = false;
				add_action( 'admin_notices', array( $this, '_dbcr_admin_notice' ) );
			}

			$dbcr_cached = false;
			if ( $dbcr_cacheable ) {
				// Try to load cached query
				$dbcr_cached = $this->dbcr_cache->load( $dbcr_queryid );
			}

			if ( $dbcr_cached !== false ) {
				// Extract cached query
				++ $this->num_cachequeries;

				$dbcr_cached       = unserialize( $dbcr_cached );
				$this->last_error  = '';
				$this->last_query  = $dbcr_cached['last_query'];
				$this->last_result = $dbcr_cached['last_result'];
				$this->col_info    = $dbcr_cached['col_info'];
				$this->num_rows    = $dbcr_cached['num_rows'];

				$return_val = $this->num_rows;

				if ( defined( 'DBCR_SAVEQUERIES' ) && DBCR_SAVEQUERIES ) {
					$this->queries[] = array( $query, $this->timer_stop(), $this->get_caller(), true );
				}
			} else {
				// Cache not found or query is not cacheable, perform query as usual
				// --- DB Cache End ---
				$this->result = @mysql_query( $query, $dbh );
				$this->num_queries ++;

				if ( defined( 'DBCR_SAVEQUERIES' ) && DBCR_SAVEQUERIES ) {
					$this->queries[] = array( $query, $this->timer_stop(), $this->get_caller(), false );
				} elseif ( defined( 'SAVEQUERIES' ) && SAVEQUERIES ) {
					$this->queries[] = array( $query, $this->timer_stop(), $this->get_caller() );
				}
			}

			// If there is an error then take note of it..
			if ( $this->last_error = mysql_error( $dbh ) ) {
				$this->print_error();

				return false;
			}

			if ( preg_match( "/^\\s*(insert|delete|update|replace|alter) /i", $query ) ) {
				$this->rows_affected = mysql_affected_rows( $dbh );
				// Take note of the insert_id
				if ( preg_match( "/^\\s*(insert|replace) /i", $query ) ) {
					$this->insert_id = mysql_insert_id( $dbh );
				}
				// Return number of rows affected
				$return_val = $this->rows_affected;

				// --- DB Cache Start ---
				++ $this->dbcr_num_dml_queries;
				// --- DB Cache End ---
			} else {
				$i = 0;
				while ( $i < @mysql_num_fields( $this->result ) ) {
					$this->col_info[ $i ] = @mysql_fetch_field( $this->result );
					$i ++;
				}
				$num_rows = 0;
				while ( $row = @mysql_fetch_object( $this->result ) ) {
					$this->last_result[ $num_rows ] = $row;
					$num_rows ++;
				}

				@mysql_free_result( $this->result );

				// Log number of rows the query returned
				// and return number of rows selected
				$this->num_rows = $num_rows;
				$return_val     = $num_rows;

				// --- DB Cache Start ---
				if ( $dbcr_cacheable && ( $dbcr_cached === false ) ) {
					$dbcr_cached = serialize( array(
						'last_query'  => $this->last_query,
						'last_result' => $this->last_result,
						'col_info'    => $this->col_info,
						'num_rows'    => $this->num_rows,
					) );
					$this->dbcr_cache->save( $dbcr_cached, $dbcr_queryid );
				}
				// --- DB Cache End ---
			}

			return $return_val;
		}
	}
}