--- /dev/null
+<?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\HttpFoundation\Session\Storage\Handler;
+
+/**
+ * Session handler using a PDO connection to read and write data.
+ *
+ * It works with MySQL, PostgreSQL, Oracle, SQL Server and SQLite and implements
+ * different locking strategies to handle concurrent access to the same session.
+ * Locking is necessary to prevent loss of data due to race conditions and to keep
+ * the session data consistent between read() and write(). With locking, requests
+ * for the same session will wait until the other one finished writing. For this
+ * reason it's best practice to close a session as early as possible to improve
+ * concurrency. PHPs internal files session handler also implements locking.
+ *
+ * Attention: Since SQLite does not support row level locks but locks the whole database,
+ * it means only one session can be accessed at a time. Even different sessions would wait
+ * for another to finish. So saving session in SQLite should only be considered for
+ * development or prototypes.
+ *
+ * Session data is a binary string that can contain non-printable characters like the null byte.
+ * For this reason it must be saved in a binary column in the database like BLOB in MySQL.
+ * Saving it in a character column could corrupt the data. You can use createTable()
+ * to initialize a correctly defined table.
+ *
+ * @see http://php.net/sessionhandlerinterface
+ *
+ * @author Fabien Potencier <fabien@symfony.com>
+ * @author Michael Williams <michael.williams@funsational.com>
+ * @author Tobias Schultze <http://tobion.de>
+ */
+class PdoSessionHandler implements \SessionHandlerInterface
+{
+ /**
+ * No locking is done. This means sessions are prone to loss of data due to
+ * race conditions of concurrent requests to the same session. The last session
+ * write will win in this case. It might be useful when you implement your own
+ * logic to deal with this like an optimistic approach.
+ */
+ const LOCK_NONE = 0;
+
+ /**
+ * Creates an application-level lock on a session. The disadvantage is that the
+ * lock is not enforced by the database and thus other, unaware parts of the
+ * application could still concurrently modify the session. The advantage is it
+ * does not require a transaction.
+ * This mode is not available for SQLite and not yet implemented for oci and sqlsrv.
+ */
+ const LOCK_ADVISORY = 1;
+
+ /**
+ * Issues a real row lock. Since it uses a transaction between opening and
+ * closing a session, you have to be careful when you use same database connection
+ * that you also use for your application logic. This mode is the default because
+ * it's the only reliable solution across DBMSs.
+ */
+ const LOCK_TRANSACTIONAL = 2;
+
+ /**
+ * @var \PDO|null PDO instance or null when not connected yet
+ */
+ private $pdo;
+
+ /**
+ * @var string|null|false DSN string or null for session.save_path or false when lazy connection disabled
+ */
+ private $dsn = false;
+
+ /**
+ * @var string Database driver
+ */
+ private $driver;
+
+ /**
+ * @var string Table name
+ */
+ private $table = 'sessions';
+
+ /**
+ * @var string Column for session id
+ */
+ private $idCol = 'sess_id';
+
+ /**
+ * @var string Column for session data
+ */
+ private $dataCol = 'sess_data';
+
+ /**
+ * @var string Column for lifetime
+ */
+ private $lifetimeCol = 'sess_lifetime';
+
+ /**
+ * @var string Column for timestamp
+ */
+ private $timeCol = 'sess_time';
+
+ /**
+ * @var string Username when lazy-connect
+ */
+ private $username = '';
+
+ /**
+ * @var string Password when lazy-connect
+ */
+ private $password = '';
+
+ /**
+ * @var array Connection options when lazy-connect
+ */
+ private $connectionOptions = array();
+
+ /**
+ * @var int The strategy for locking, see constants
+ */
+ private $lockMode = self::LOCK_TRANSACTIONAL;
+
+ /**
+ * It's an array to support multiple reads before closing which is manual, non-standard usage.
+ *
+ * @var \PDOStatement[] An array of statements to release advisory locks
+ */
+ private $unlockStatements = array();
+
+ /**
+ * @var bool True when the current session exists but expired according to session.gc_maxlifetime
+ */
+ private $sessionExpired = false;
+
+ /**
+ * @var bool Whether a transaction is active
+ */
+ private $inTransaction = false;
+
+ /**
+ * @var bool Whether gc() has been called
+ */
+ private $gcCalled = false;
+
+ /**
+ * Constructor.
+ *
+ * You can either pass an existing database connection as PDO instance or
+ * pass a DSN string that will be used to lazy-connect to the database
+ * when the session is actually used. Furthermore it's possible to pass null
+ * which will then use the session.save_path ini setting as PDO DSN parameter.
+ *
+ * List of available options:
+ * * db_table: The name of the table [default: sessions]
+ * * db_id_col: The column where to store the session id [default: sess_id]
+ * * db_data_col: The column where to store the session data [default: sess_data]
+ * * db_lifetime_col: The column where to store the lifetime [default: sess_lifetime]
+ * * db_time_col: The column where to store the timestamp [default: sess_time]
+ * * db_username: The username when lazy-connect [default: '']
+ * * db_password: The password when lazy-connect [default: '']
+ * * db_connection_options: An array of driver-specific connection options [default: array()]
+ * * lock_mode: The strategy for locking, see constants [default: LOCK_TRANSACTIONAL]
+ *
+ * @param \PDO|string|null $pdoOrDsn A \PDO instance or DSN string or null
+ * @param array $options An associative array of options
+ *
+ * @throws \InvalidArgumentException When PDO error mode is not PDO::ERRMODE_EXCEPTION
+ */
+ public function __construct($pdoOrDsn = null, array $options = array())
+ {
+ if ($pdoOrDsn instanceof \PDO) {
+ if (\PDO::ERRMODE_EXCEPTION !== $pdoOrDsn->getAttribute(\PDO::ATTR_ERRMODE)) {
+ throw new \InvalidArgumentException(sprintf('"%s" requires PDO error mode attribute be set to throw Exceptions (i.e. $pdo->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION))', __CLASS__));
+ }
+
+ $this->pdo = $pdoOrDsn;
+ $this->driver = $this->pdo->getAttribute(\PDO::ATTR_DRIVER_NAME);
+ } else {
+ $this->dsn = $pdoOrDsn;
+ }
+
+ $this->table = isset($options['db_table']) ? $options['db_table'] : $this->table;
+ $this->idCol = isset($options['db_id_col']) ? $options['db_id_col'] : $this->idCol;
+ $this->dataCol = isset($options['db_data_col']) ? $options['db_data_col'] : $this->dataCol;
+ $this->lifetimeCol = isset($options['db_lifetime_col']) ? $options['db_lifetime_col'] : $this->lifetimeCol;
+ $this->timeCol = isset($options['db_time_col']) ? $options['db_time_col'] : $this->timeCol;
+ $this->username = isset($options['db_username']) ? $options['db_username'] : $this->username;
+ $this->password = isset($options['db_password']) ? $options['db_password'] : $this->password;
+ $this->connectionOptions = isset($options['db_connection_options']) ? $options['db_connection_options'] : $this->connectionOptions;
+ $this->lockMode = isset($options['lock_mode']) ? $options['lock_mode'] : $this->lockMode;
+ }
+
+ /**
+ * Creates the table to store sessions which can be called once for setup.
+ *
+ * Session ID is saved in a column of maximum length 128 because that is enough even
+ * for a 512 bit configured session.hash_function like Whirlpool. Session data is
+ * saved in a BLOB. One could also use a shorter inlined varbinary column
+ * if one was sure the data fits into it.
+ *
+ * @throws \PDOException When the table already exists
+ * @throws \DomainException When an unsupported PDO driver is used
+ */
+ public function createTable()
+ {
+ // connect if we are not yet
+ $this->getConnection();
+
+ switch ($this->driver) {
+ case 'mysql':
+ // We use varbinary for the ID column because it prevents unwanted conversions:
+ // - character set conversions between server and client
+ // - trailing space removal
+ // - case-insensitivity
+ // - language processing like é == e
+ $sql = "CREATE TABLE $this->table ($this->idCol VARBINARY(128) NOT NULL PRIMARY KEY, $this->dataCol BLOB NOT NULL, $this->lifetimeCol MEDIUMINT NOT NULL, $this->timeCol INTEGER UNSIGNED NOT NULL) COLLATE utf8_bin, ENGINE = InnoDB";
+ break;
+ case 'sqlite':
+ $sql = "CREATE TABLE $this->table ($this->idCol TEXT NOT NULL PRIMARY KEY, $this->dataCol BLOB NOT NULL, $this->lifetimeCol INTEGER NOT NULL, $this->timeCol INTEGER NOT NULL)";
+ break;
+ case 'pgsql':
+ $sql = "CREATE TABLE $this->table ($this->idCol VARCHAR(128) NOT NULL PRIMARY KEY, $this->dataCol BYTEA NOT NULL, $this->lifetimeCol INTEGER NOT NULL, $this->timeCol INTEGER NOT NULL)";
+ break;
+ case 'oci':
+ $sql = "CREATE TABLE $this->table ($this->idCol VARCHAR2(128) NOT NULL PRIMARY KEY, $this->dataCol BLOB NOT NULL, $this->lifetimeCol INTEGER NOT NULL, $this->timeCol INTEGER NOT NULL)";
+ break;
+ case 'sqlsrv':
+ $sql = "CREATE TABLE $this->table ($this->idCol VARCHAR(128) NOT NULL PRIMARY KEY, $this->dataCol VARBINARY(MAX) NOT NULL, $this->lifetimeCol INTEGER NOT NULL, $this->timeCol INTEGER NOT NULL)";
+ break;
+ default:
+ throw new \DomainException(sprintf('Creating the session table is currently not implemented for PDO driver "%s".', $this->driver));
+ }
+
+ try {
+ $this->pdo->exec($sql);
+ } catch (\PDOException $e) {
+ $this->rollback();
+
+ throw $e;
+ }
+ }
+
+ /**
+ * Returns true when the current session exists but expired according to session.gc_maxlifetime.
+ *
+ * Can be used to distinguish between a new session and one that expired due to inactivity.
+ *
+ * @return bool Whether current session expired
+ */
+ public function isSessionExpired()
+ {
+ return $this->sessionExpired;
+ }
+
+ /**
+ * {@inheritdoc}
+ */
+ public function open($savePath, $sessionName)
+ {
+ if (null === $this->pdo) {
+ $this->connect($this->dsn ?: $savePath);
+ }
+
+ return true;
+ }
+
+ /**
+ * {@inheritdoc}
+ */
+ public function read($sessionId)
+ {
+ try {
+ return $this->doRead($sessionId);
+ } catch (\PDOException $e) {
+ $this->rollback();
+
+ throw $e;
+ }
+ }
+
+ /**
+ * {@inheritdoc}
+ */
+ public function gc($maxlifetime)
+ {
+ // We delay gc() to close() so that it is executed outside the transactional and blocking read-write process.
+ // This way, pruning expired sessions does not block them from being started while the current session is used.
+ $this->gcCalled = true;
+
+ return true;
+ }
+
+ /**
+ * {@inheritdoc}
+ */
+ public function destroy($sessionId)
+ {
+ // delete the record associated with this id
+ $sql = "DELETE FROM $this->table WHERE $this->idCol = :id";
+
+ try {
+ $stmt = $this->pdo->prepare($sql);
+ $stmt->bindParam(':id', $sessionId, \PDO::PARAM_STR);
+ $stmt->execute();
+ } catch (\PDOException $e) {
+ $this->rollback();
+
+ throw $e;
+ }
+
+ return true;
+ }
+
+ /**
+ * {@inheritdoc}
+ */
+ public function write($sessionId, $data)
+ {
+ $maxlifetime = (int) ini_get('session.gc_maxlifetime');
+
+ try {
+ // We use a single MERGE SQL query when supported by the database.
+ $mergeStmt = $this->getMergeStatement($sessionId, $data, $maxlifetime);
+ if (null !== $mergeStmt) {
+ $mergeStmt->execute();
+
+ return true;
+ }
+
+ $updateStmt = $this->pdo->prepare(
+ "UPDATE $this->table SET $this->dataCol = :data, $this->lifetimeCol = :lifetime, $this->timeCol = :time WHERE $this->idCol = :id"
+ );
+ $updateStmt->bindParam(':id', $sessionId, \PDO::PARAM_STR);
+ $updateStmt->bindParam(':data', $data, \PDO::PARAM_LOB);
+ $updateStmt->bindParam(':lifetime', $maxlifetime, \PDO::PARAM_INT);
+ $updateStmt->bindValue(':time', time(), \PDO::PARAM_INT);
+ $updateStmt->execute();
+
+ // When MERGE is not supported, like in Postgres < 9.5, we have to use this approach that can result in
+ // duplicate key errors when the same session is written simultaneously (given the LOCK_NONE behavior).
+ // We can just catch such an error and re-execute the update. This is similar to a serializable
+ // transaction with retry logic on serialization failures but without the overhead and without possible
+ // false positives due to longer gap locking.
+ if (!$updateStmt->rowCount()) {
+ try {
+ $insertStmt = $this->pdo->prepare(
+ "INSERT INTO $this->table ($this->idCol, $this->dataCol, $this->lifetimeCol, $this->timeCol) VALUES (:id, :data, :lifetime, :time)"
+ );
+ $insertStmt->bindParam(':id', $sessionId, \PDO::PARAM_STR);
+ $insertStmt->bindParam(':data', $data, \PDO::PARAM_LOB);
+ $insertStmt->bindParam(':lifetime', $maxlifetime, \PDO::PARAM_INT);
+ $insertStmt->bindValue(':time', time(), \PDO::PARAM_INT);
+ $insertStmt->execute();
+ } catch (\PDOException $e) {
+ // Handle integrity violation SQLSTATE 23000 (or a subclass like 23505 in Postgres) for duplicate keys
+ if (0 === strpos($e->getCode(), '23')) {
+ $updateStmt->execute();
+ } else {
+ throw $e;
+ }
+ }
+ }
+ } catch (\PDOException $e) {
+ $this->rollback();
+
+ throw $e;
+ }
+
+ return true;
+ }
+
+ /**
+ * {@inheritdoc}
+ */
+ public function close()
+ {
+ $this->commit();
+
+ while ($unlockStmt = array_shift($this->unlockStatements)) {
+ $unlockStmt->execute();
+ }
+
+ if ($this->gcCalled) {
+ $this->gcCalled = false;
+
+ // delete the session records that have expired
+ $sql = "DELETE FROM $this->table WHERE $this->lifetimeCol + $this->timeCol < :time";
+
+ $stmt = $this->pdo->prepare($sql);
+ $stmt->bindValue(':time', time(), \PDO::PARAM_INT);
+ $stmt->execute();
+ }
+
+ if (false !== $this->dsn) {
+ $this->pdo = null; // only close lazy-connection
+ }
+
+ return true;
+ }
+
+ /**
+ * Lazy-connects to the database.
+ *
+ * @param string $dsn DSN string
+ */
+ private function connect($dsn)
+ {
+ $this->pdo = new \PDO($dsn, $this->username, $this->password, $this->connectionOptions);
+ $this->pdo->setAttribute(\PDO::ATTR_ERRMODE, \PDO::ERRMODE_EXCEPTION);
+ $this->driver = $this->pdo->getAttribute(\PDO::ATTR_DRIVER_NAME);
+ }
+
+ /**
+ * Helper method to begin a transaction.
+ *
+ * Since SQLite does not support row level locks, we have to acquire a reserved lock
+ * on the database immediately. Because of https://bugs.php.net/42766 we have to create
+ * such a transaction manually which also means we cannot use PDO::commit or
+ * PDO::rollback or PDO::inTransaction for SQLite.
+ *
+ * Also MySQLs default isolation, REPEATABLE READ, causes deadlock for different sessions
+ * due to http://www.mysqlperformanceblog.com/2013/12/12/one-more-innodb-gap-lock-to-avoid/ .
+ * So we change it to READ COMMITTED.
+ */
+ private function beginTransaction()
+ {
+ if (!$this->inTransaction) {
+ if ('sqlite' === $this->driver) {
+ $this->pdo->exec('BEGIN IMMEDIATE TRANSACTION');
+ } else {
+ if ('mysql' === $this->driver) {
+ $this->pdo->exec('SET TRANSACTION ISOLATION LEVEL READ COMMITTED');
+ }
+ $this->pdo->beginTransaction();
+ }
+ $this->inTransaction = true;
+ }
+ }
+
+ /**
+ * Helper method to commit a transaction.
+ */
+ private function commit()
+ {
+ if ($this->inTransaction) {
+ try {
+ // commit read-write transaction which also releases the lock
+ if ('sqlite' === $this->driver) {
+ $this->pdo->exec('COMMIT');
+ } else {
+ $this->pdo->commit();
+ }
+ $this->inTransaction = false;
+ } catch (\PDOException $e) {
+ $this->rollback();
+
+ throw $e;
+ }
+ }
+ }
+
+ /**
+ * Helper method to rollback a transaction.
+ */
+ private function rollback()
+ {
+ // We only need to rollback if we are in a transaction. Otherwise the resulting
+ // error would hide the real problem why rollback was called. We might not be
+ // in a transaction when not using the transactional locking behavior or when
+ // two callbacks (e.g. destroy and write) are invoked that both fail.
+ if ($this->inTransaction) {
+ if ('sqlite' === $this->driver) {
+ $this->pdo->exec('ROLLBACK');
+ } else {
+ $this->pdo->rollBack();
+ }
+ $this->inTransaction = false;
+ }
+ }
+
+ /**
+ * Reads the session data in respect to the different locking strategies.
+ *
+ * We need to make sure we do not return session data that is already considered garbage according
+ * to the session.gc_maxlifetime setting because gc() is called after read() and only sometimes.
+ *
+ * @param string $sessionId Session ID
+ *
+ * @return string The session data
+ */
+ private function doRead($sessionId)
+ {
+ $this->sessionExpired = false;
+
+ if (self::LOCK_ADVISORY === $this->lockMode) {
+ $this->unlockStatements[] = $this->doAdvisoryLock($sessionId);
+ }
+
+ $selectSql = $this->getSelectSql();
+ $selectStmt = $this->pdo->prepare($selectSql);
+ $selectStmt->bindParam(':id', $sessionId, \PDO::PARAM_STR);
+
+ do {
+ $selectStmt->execute();
+ $sessionRows = $selectStmt->fetchAll(\PDO::FETCH_NUM);
+
+ if ($sessionRows) {
+ if ($sessionRows[0][1] + $sessionRows[0][2] < time()) {
+ $this->sessionExpired = true;
+
+ return '';
+ }
+
+ return is_resource($sessionRows[0][0]) ? stream_get_contents($sessionRows[0][0]) : $sessionRows[0][0];
+ }
+
+ if (self::LOCK_TRANSACTIONAL === $this->lockMode && 'sqlite' !== $this->driver) {
+ // Exclusive-reading of non-existent rows does not block, so we need to do an insert to block
+ // until other connections to the session are committed.
+ try {
+ $insertStmt = $this->pdo->prepare(
+ "INSERT INTO $this->table ($this->idCol, $this->dataCol, $this->lifetimeCol, $this->timeCol) VALUES (:id, :data, :lifetime, :time)"
+ );
+ $insertStmt->bindParam(':id', $sessionId, \PDO::PARAM_STR);
+ $insertStmt->bindValue(':data', '', \PDO::PARAM_LOB);
+ $insertStmt->bindValue(':lifetime', 0, \PDO::PARAM_INT);
+ $insertStmt->bindValue(':time', time(), \PDO::PARAM_INT);
+ $insertStmt->execute();
+ } catch (\PDOException $e) {
+ // Catch duplicate key error because other connection created the session already.
+ // It would only not be the case when the other connection destroyed the session.
+ if (0 === strpos($e->getCode(), '23')) {
+ // Retrieve finished session data written by concurrent connection by restarting the loop.
+ // We have to start a new transaction as a failed query will mark the current transaction as
+ // aborted in PostgreSQL and disallow further queries within it.
+ $this->rollback();
+ $this->beginTransaction();
+ continue;
+ }
+
+ throw $e;
+ }
+ }
+
+ return '';
+ } while (true);
+ }
+
+ /**
+ * Executes an application-level lock on the database.
+ *
+ * @param string $sessionId Session ID
+ *
+ * @return \PDOStatement The statement that needs to be executed later to release the lock
+ *
+ * @throws \DomainException When an unsupported PDO driver is used
+ *
+ * @todo implement missing advisory locks
+ * - for oci using DBMS_LOCK.REQUEST
+ * - for sqlsrv using sp_getapplock with LockOwner = Session
+ */
+ private function doAdvisoryLock($sessionId)
+ {
+ switch ($this->driver) {
+ case 'mysql':
+ // should we handle the return value? 0 on timeout, null on error
+ // we use a timeout of 50 seconds which is also the default for innodb_lock_wait_timeout
+ $stmt = $this->pdo->prepare('SELECT GET_LOCK(:key, 50)');
+ $stmt->bindValue(':key', $sessionId, \PDO::PARAM_STR);
+ $stmt->execute();
+
+ $releaseStmt = $this->pdo->prepare('DO RELEASE_LOCK(:key)');
+ $releaseStmt->bindValue(':key', $sessionId, \PDO::PARAM_STR);
+
+ return $releaseStmt;
+ case 'pgsql':
+ // Obtaining an exclusive session level advisory lock requires an integer key.
+ // So we convert the HEX representation of the session id to an integer.
+ // Since integers are signed, we have to skip one hex char to fit in the range.
+ if (4 === PHP_INT_SIZE) {
+ $sessionInt1 = hexdec(substr($sessionId, 0, 7));
+ $sessionInt2 = hexdec(substr($sessionId, 7, 7));
+
+ $stmt = $this->pdo->prepare('SELECT pg_advisory_lock(:key1, :key2)');
+ $stmt->bindValue(':key1', $sessionInt1, \PDO::PARAM_INT);
+ $stmt->bindValue(':key2', $sessionInt2, \PDO::PARAM_INT);
+ $stmt->execute();
+
+ $releaseStmt = $this->pdo->prepare('SELECT pg_advisory_unlock(:key1, :key2)');
+ $releaseStmt->bindValue(':key1', $sessionInt1, \PDO::PARAM_INT);
+ $releaseStmt->bindValue(':key2', $sessionInt2, \PDO::PARAM_INT);
+ } else {
+ $sessionBigInt = hexdec(substr($sessionId, 0, 15));
+
+ $stmt = $this->pdo->prepare('SELECT pg_advisory_lock(:key)');
+ $stmt->bindValue(':key', $sessionBigInt, \PDO::PARAM_INT);
+ $stmt->execute();
+
+ $releaseStmt = $this->pdo->prepare('SELECT pg_advisory_unlock(:key)');
+ $releaseStmt->bindValue(':key', $sessionBigInt, \PDO::PARAM_INT);
+ }
+
+ return $releaseStmt;
+ case 'sqlite':
+ throw new \DomainException('SQLite does not support advisory locks.');
+ default:
+ throw new \DomainException(sprintf('Advisory locks are currently not implemented for PDO driver "%s".', $this->driver));
+ }
+ }
+
+ /**
+ * Return a locking or nonlocking SQL query to read session information.
+ *
+ * @return string The SQL string
+ *
+ * @throws \DomainException When an unsupported PDO driver is used
+ */
+ private function getSelectSql()
+ {
+ if (self::LOCK_TRANSACTIONAL === $this->lockMode) {
+ $this->beginTransaction();
+
+ switch ($this->driver) {
+ case 'mysql':
+ case 'oci':
+ case 'pgsql':
+ return "SELECT $this->dataCol, $this->lifetimeCol, $this->timeCol FROM $this->table WHERE $this->idCol = :id FOR UPDATE";
+ case 'sqlsrv':
+ return "SELECT $this->dataCol, $this->lifetimeCol, $this->timeCol FROM $this->table WITH (UPDLOCK, ROWLOCK) WHERE $this->idCol = :id";
+ case 'sqlite':
+ // we already locked when starting transaction
+ break;
+ default:
+ throw new \DomainException(sprintf('Transactional locks are currently not implemented for PDO driver "%s".', $this->driver));
+ }
+ }
+
+ return "SELECT $this->dataCol, $this->lifetimeCol, $this->timeCol FROM $this->table WHERE $this->idCol = :id";
+ }
+
+ /**
+ * Returns a merge/upsert (i.e. insert or update) statement when supported by the database for writing session data.
+ *
+ * @param string $sessionId Session ID
+ * @param string $data Encoded session data
+ * @param int $maxlifetime session.gc_maxlifetime
+ *
+ * @return \PDOStatement|null The merge statement or null when not supported
+ */
+ private function getMergeStatement($sessionId, $data, $maxlifetime)
+ {
+ $mergeSql = null;
+ switch (true) {
+ case 'mysql' === $this->driver:
+ $mergeSql = "INSERT INTO $this->table ($this->idCol, $this->dataCol, $this->lifetimeCol, $this->timeCol) VALUES (:id, :data, :lifetime, :time) ".
+ "ON DUPLICATE KEY UPDATE $this->dataCol = VALUES($this->dataCol), $this->lifetimeCol = VALUES($this->lifetimeCol), $this->timeCol = VALUES($this->timeCol)";
+ break;
+ case 'oci' === $this->driver:
+ // DUAL is Oracle specific dummy table
+ $mergeSql = "MERGE INTO $this->table USING DUAL ON ($this->idCol = ?) ".
+ "WHEN NOT MATCHED THEN INSERT ($this->idCol, $this->dataCol, $this->lifetimeCol, $this->timeCol) VALUES (?, ?, ?, ?) ".
+ "WHEN MATCHED THEN UPDATE SET $this->dataCol = ?, $this->lifetimeCol = ?, $this->timeCol = ?";
+ break;
+ case 'sqlsrv' === $this->driver && version_compare($this->pdo->getAttribute(\PDO::ATTR_SERVER_VERSION), '10', '>='):
+ // MERGE is only available since SQL Server 2008 and must be terminated by semicolon
+ // It also requires HOLDLOCK according to http://weblogs.sqlteam.com/dang/archive/2009/01/31/UPSERT-Race-Condition-With-MERGE.aspx
+ $mergeSql = "MERGE INTO $this->table WITH (HOLDLOCK) USING (SELECT 1 AS dummy) AS src ON ($this->idCol = ?) ".
+ "WHEN NOT MATCHED THEN INSERT ($this->idCol, $this->dataCol, $this->lifetimeCol, $this->timeCol) VALUES (?, ?, ?, ?) ".
+ "WHEN MATCHED THEN UPDATE SET $this->dataCol = ?, $this->lifetimeCol = ?, $this->timeCol = ?;";
+ break;
+ case 'sqlite' === $this->driver:
+ $mergeSql = "INSERT OR REPLACE INTO $this->table ($this->idCol, $this->dataCol, $this->lifetimeCol, $this->timeCol) VALUES (:id, :data, :lifetime, :time)";
+ break;
+ case 'pgsql' === $this->driver && version_compare($this->pdo->getAttribute(\PDO::ATTR_SERVER_VERSION), '9.5', '>='):
+ $mergeSql = "INSERT INTO $this->table ($this->idCol, $this->dataCol, $this->lifetimeCol, $this->timeCol) VALUES (:id, :data, :lifetime, :time) ".
+ "ON CONFLICT ($this->idCol) DO UPDATE SET ($this->dataCol, $this->lifetimeCol, $this->timeCol) = (EXCLUDED.$this->dataCol, EXCLUDED.$this->lifetimeCol, EXCLUDED.$this->timeCol)";
+ break;
+ }
+
+ if (null !== $mergeSql) {
+ $mergeStmt = $this->pdo->prepare($mergeSql);
+
+ if ('sqlsrv' === $this->driver || 'oci' === $this->driver) {
+ $mergeStmt->bindParam(1, $sessionId, \PDO::PARAM_STR);
+ $mergeStmt->bindParam(2, $sessionId, \PDO::PARAM_STR);
+ $mergeStmt->bindParam(3, $data, \PDO::PARAM_LOB);
+ $mergeStmt->bindParam(4, $maxlifetime, \PDO::PARAM_INT);
+ $mergeStmt->bindValue(5, time(), \PDO::PARAM_INT);
+ $mergeStmt->bindParam(6, $data, \PDO::PARAM_LOB);
+ $mergeStmt->bindParam(7, $maxlifetime, \PDO::PARAM_INT);
+ $mergeStmt->bindValue(8, time(), \PDO::PARAM_INT);
+ } else {
+ $mergeStmt->bindParam(':id', $sessionId, \PDO::PARAM_STR);
+ $mergeStmt->bindParam(':data', $data, \PDO::PARAM_LOB);
+ $mergeStmt->bindParam(':lifetime', $maxlifetime, \PDO::PARAM_INT);
+ $mergeStmt->bindValue(':time', time(), \PDO::PARAM_INT);
+ }
+
+ return $mergeStmt;
+ }
+ }
+
+ /**
+ * Return a PDO instance.
+ *
+ * @return \PDO
+ */
+ protected function getConnection()
+ {
+ if (null === $this->pdo) {
+ $this->connect($this->dsn ?: ini_get('session.save_path'));
+ }
+
+ return $this->pdo;
+ }
+}
projects / yaffs-website / blobdiff