Fix PHP 8.5 compatibility issue with MySQL driver.

Author: pocketarc

system/database/drivers/pdo/subdrivers/pdo_mysql_driver.php

@@ -143,34 +143,65 @@ public function db_connect($persistent = FALSE)
 
 			if ( ! empty($sql))
 			{
-				if (empty($this->options[PDO::MYSQL_ATTR_INIT_COMMAND]))
+				if (class_exists('Pdo\\Mysql'))
 				{
-					$this->options[PDO::MYSQL_ATTR_INIT_COMMAND] = 'SET SESSION sql_mode = '.$sql;
+					$constant = constant('Pdo\\Mysql::ATTR_INIT_COMMAND');
+				} else {
+					$constant = PDO::MYSQL_ATTR_INIT_COMMAND;
+				}
+
+				if (empty($this->options[$constant]))
+				{
+					$this->options[$constant] = 'SET SESSION sql_mode = '.$sql;
 				}
 				else
 				{
-					$this->options[PDO::MYSQL_ATTR_INIT_COMMAND] .= ', @@session.sql_mode = '.$sql;
+					$this->options[$constant] .= ', @@session.sql_mode = '.$sql;
 				}
 			}
 		}
 
 		if ($this->compress === TRUE)
 		{
-			$this->options[PDO::MYSQL_ATTR_COMPRESS] = TRUE;
+			if (class_exists('Pdo\\Mysql'))
+			{
+				$constant = constant('Pdo\\Mysql::ATTR_COMPRESS');
+			} else {
+				$constant = PDO::MYSQL_ATTR_COMPRESS;
+			}
+
+			$this->options[$constant] = TRUE;
 		}
 
 		if (is_array($this->encrypt))
 		{
+			if (class_exists('Pdo\\Mysql'))
+			{
+				$sslKey = constant('Pdo\\Mysql::ATTR_SSL_KEY');
+				$sslCert = constant('Pdo\\Mysql::ATTR_SSL_CERT');
+				$sslCA = constant('Pdo\\Mysql::ATTR_SSL_CA');
+				$sslCAPath = constant('Pdo\\Mysql::ATTR_SSL_CAPATH');
+				$sslCipher = constant('Pdo\\Mysql::ATTR_SSL_CIPHER');
+				$verify = constant('Pdo\\Mysql::ATTR_SSL_VERIFY_SERVER_CERT');
+			} else {
+				$sslKey = PDO::MYSQL_ATTR_SSL_KEY;
+				$sslCert = PDO::MYSQL_ATTR_SSL_CERT;
+				$sslCA = PDO::MYSQL_ATTR_SSL_CA;
+				$sslCAPath = PDO::MYSQL_ATTR_SSL_CAPATH;
+				$sslCipher = PDO::MYSQL_ATTR_SSL_CIPHER;
+				$verify = defined('PDO::MYSQL_ATTR_SSL_VERIFY_SERVER_CERT') ? PDO::MYSQL_ATTR_SSL_VERIFY_SERVER_CERT : null;
+			}
+
 			$ssl = array();
-			empty($this->encrypt['ssl_key'])    OR $ssl[PDO::MYSQL_ATTR_SSL_KEY]    = $this->encrypt['ssl_key'];
-			empty($this->encrypt['ssl_cert'])   OR $ssl[PDO::MYSQL_ATTR_SSL_CERT]   = $this->encrypt['ssl_cert'];
-			empty($this->encrypt['ssl_ca'])     OR $ssl[PDO::MYSQL_ATTR_SSL_CA]     = $this->encrypt['ssl_ca'];
-			empty($this->encrypt['ssl_capath']) OR $ssl[PDO::MYSQL_ATTR_SSL_CAPATH] = $this->encrypt['ssl_capath'];
-			empty($this->encrypt['ssl_cipher']) OR $ssl[PDO::MYSQL_ATTR_SSL_CIPHER] = $this->encrypt['ssl_cipher'];
+			empty($this->encrypt['ssl_key'])    OR $ssl[$sslKey]    = $this->encrypt['ssl_key'];
+			empty($this->encrypt['ssl_cert'])   OR $ssl[$sslCert]   = $this->encrypt['ssl_cert'];
+			empty($this->encrypt['ssl_ca'])     OR $ssl[$sslCA]     = $this->encrypt['ssl_ca'];
+			empty($this->encrypt['ssl_capath']) OR $ssl[$sslCAPath] = $this->encrypt['ssl_capath'];
+			empty($this->encrypt['ssl_cipher']) OR $ssl[$sslCipher] = $this->encrypt['ssl_cipher'];
 
-			if (defined('PDO::MYSQL_ATTR_SSL_VERIFY_SERVER_CERT') && isset($this->encrypt['ssl_verify']))
+			if ($verify && isset($this->encrypt['ssl_verify']))
 			{
-				$ssl[PDO::MYSQL_ATTR_SSL_VERIFY_SERVER_CERT] = $this->encrypt['ssl_verify'];
+				$ssl[$verify] = $this->encrypt['ssl_verify'];
 			}
 
 			// DO NOT use array_merge() here!