Merge branch '3.0-stable' into develop

18 files changed, 270 insertions, 104 deletions

diff --git a/system/core/Security.php b/system/core/Security.php
index 36dea4cf2..e79bf8aff 100644
--- a/system/core/Security.php
+++ b/system/core/Security.php
@@ -593,6 +593,22 @@ class CI_Security {
 			return FALSE;
 		}
 
+		if (function_exists('random_bytes'))
+		{
+			try
+			{
+				// The cast is required to avoid TypeError
+				return random_bytes((int) $length);
+			}
+			catch (Exception $e)
+			{
+				// If random_bytes() can't do the job, we can't either ...
+				// There's no point in using fallbacks.
+				log_message('error', $e->getMessage());
+				return FALSE;
+			}
+		}
+
 		// Unfortunately, none of the following PRNGs is guaranteed to exist ...
 		if (defined('MCRYPT_DEV_URANDOM') && ($output = mcrypt_create_iv($length, MCRYPT_DEV_URANDOM)) !== FALSE)
 		{
diff --git a/system/database/DB_driver.php b/system/database/DB_driver.php
index 418de27c8..885a814be 100644
--- a/system/database/DB_driver.php
+++ b/system/database/DB_driver.php
@@ -499,6 +499,18 @@ abstract class CI_DB_driver {
 	// --------------------------------------------------------------------
 
 	/**
+	 * Last error
+	 *
+	 * @return	array
+	 */
+	public function error()
+	{
+		return array('code' => NULL, 'message' => NULL);
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
 	 * Set client character set
 	 *
 	 * @param	string
diff --git a/system/database/DB_forge.php b/system/database/DB_forge.php
index f9cf76a14..1546e40c0 100644
--- a/system/database/DB_forge.php
+++ b/system/database/DB_forge.php
@@ -780,10 +780,6 @@ abstract class CI_DB_forge {
 					case 'ENUM':
 					case 'SET':
 						$attributes['CONSTRAINT'] = $this->db->escape($attributes['CONSTRAINT']);
-						$field['length'] = is_array($attributes['CONSTRAINT'])
-							? "('".implode("','", $attributes['CONSTRAINT'])."')"
-							: '('.$attributes['CONSTRAINT'].')';
-						break;
 					default:
 						$field['length'] = is_array($attributes['CONSTRAINT'])
 							? '('.implode(',', $attributes['CONSTRAINT']).')'
diff --git a/system/database/DB_query_builder.php b/system/database/DB_query_builder.php
index cf1100d27..7a3d2f594 100644
--- a/system/database/DB_query_builder.php
+++ b/system/database/DB_query_builder.php
@@ -1379,7 +1379,7 @@ abstract class CI_DB_query_builder extends CI_DB_driver {
 			$this->from($table);
 		}
 
-		$result = ($this->qb_distinct === TRUE)
+		$result = ($this->qb_distinct === TRUE OR ! empty($this->qb_orderby))
 			? $this->query($this->_count_string.$this->protect_identifiers('numrows')."\nFROM (\n".$this->_compile_select()."\n) CI_count_all_results")
 			: $this->query($this->_compile_select($this->_count_string.$this->protect_identifiers('numrows')));
 
diff --git a/system/database/drivers/mssql/mssql_driver.php b/system/database/drivers/mssql/mssql_driver.php
index 883973ae1..b9e310a3a 100644
--- a/system/database/drivers/mssql/mssql_driver.php
+++ b/system/database/drivers/mssql/mssql_driver.php
@@ -267,7 +267,7 @@ class CI_DB_mssql_driver extends CI_DB {
 	 */
 	protected function _version()
 	{
-		return 'SELECT @@VERSION AS ver';
+		return "SELECT SERVERPROPERTY('ProductVersion') AS ver";
 	}
 
 	// --------------------------------------------------------------------
diff --git a/system/database/drivers/oci8/oci8_driver.php b/system/database/drivers/oci8/oci8_driver.php
index 916ddeb90..206924d06 100644
--- a/system/database/drivers/oci8/oci8_driver.php
+++ b/system/database/drivers/oci8/oci8_driver.php
@@ -252,12 +252,16 @@ class CI_DB_oci8_driver extends CI_DB {
 			return $this->data_cache['version'];
 		}
 
-		if ( ! $this->conn_id OR ($version = oci_server_version($this->conn_id)) === FALSE)
+		if ( ! $this->conn_id OR ($version_string = oci_server_version($this->conn_id)) === FALSE)
 		{
 			return FALSE;
 		}
+		elseif (preg_match('#Release\s(\d+(?:\.\d+)+)#', $version_string, $match))
+		{
+			return $this->data_cache['version'] = $match[1];
+		}
 
-		return $this->data_cache['version'] = $version;
+		return FALSE;
 	}
 
 	// --------------------------------------------------------------------
diff --git a/system/database/drivers/pdo/subdrivers/pdo_oci_driver.php b/system/database/drivers/pdo/subdrivers/pdo_oci_driver.php
index d17e311f7..4791ab157 100644
--- a/system/database/drivers/pdo/subdrivers/pdo_oci_driver.php
+++ b/system/database/drivers/pdo/subdrivers/pdo_oci_driver.php
@@ -130,6 +130,29 @@ class CI_DB_pdo_oci_driver extends CI_DB_pdo_driver {
 	// --------------------------------------------------------------------
 
 	/**
+	 * Database version number
+	 *
+	 * @return	string
+	 */
+	public function version()
+	{
+		if (isset($this->data_cache['version']))
+		{
+			return $this->data_cache['version'];
+		}
+
+		$version_string = parent::version();
+		if (preg_match('#Release\s(?<version>\d+(?:\.\d+)+)#', $version_string, $match))
+		{
+			return $this->data_cache['version'] = $match[1];
+		}
+
+		return FALSE;
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
 	 * Show table query
 	 *
 	 * Generates a platform-specific query string so that the table names can be fetched
diff --git a/system/helpers/captcha_helper.php b/system/helpers/captcha_helper.php
index 85bcfb5a0..03c1dd852 100644
--- a/system/helpers/captcha_helper.php
+++ b/system/helpers/captcha_helper.php
@@ -171,7 +171,8 @@ if ( ! function_exists('create_captcha'))
 				$byte_index = $word_index = 0;
 				while ($word_index < $word_length)
 				{
-					if (($rand_index = unpack('C', $bytes[$byte_index++])) > $rand_max)
+					list(, $rand_index) = unpack('C', $bytes[$byte_index++]);
+					if ($rand_index > $rand_max)
 					{
 						// Was this the last byte we have?
 						// If so, try to fetch more.
diff --git a/system/helpers/form_helper.php b/system/helpers/form_helper.php
index fd807769a..37dafd913 100644
--- a/system/helpers/form_helper.php
+++ b/system/helpers/form_helper.php
@@ -769,12 +769,11 @@ if ( ! function_exists('set_checkbox'))
 		{
 			return $CI->form_validation->set_checkbox($field, $value, $default);
 		}
-		elseif (($input = $CI->input->post($field, FALSE)) === NULL)
-		{
-			return ($default === TRUE) ? ' checked="checked"' : '';
-		}
 
+		// Form inputs are always strings ...
 		$value = (string) $value;
+		$input = $CI->input->post($field, FALSE);
+
 		if (is_array($input))
 		{
 			// Note: in_array('', array(0)) returns TRUE, do not use it
@@ -789,7 +788,13 @@ if ( ! function_exists('set_checkbox'))
 			return '';
 		}
 
-		return ($input === $value) ? ' checked="checked"' : '';
+		// Unchecked checkbox and radio inputs are not even submitted by browsers ...
+		if ($CI->input->method() === 'post')
+		{
+			return ($input === 'value') ? ' checked="checked"' : '';
+		}
+
+		return ($default === TRUE) ? ' checked="checked"' : '';
 	}
 }
 
@@ -816,12 +821,32 @@ if ( ! function_exists('set_radio'))
 		{
 			return $CI->form_validation->set_radio($field, $value, $default);
 		}
-		elseif (($input = $CI->input->post($field, FALSE)) === NULL)
+
+		// Form inputs are always strings ...
+		$value = (string) $value;
+		$input = $CI->input->post($field, FALSE);
+
+		if (is_array($input))
+		{
+			// Note: in_array('', array(0)) returns TRUE, do not use it
+			foreach ($input as &$v)
+			{
+				if ($value === $v)
+				{
+					return ' checked="checked"';
+				}
+			}
+
+			return '';
+		}
+
+		// Unchecked checkbox and radio inputs are not even submitted by browsers ...
+		if ($CI->input->method() === 'post')
 		{
-			return ($default === TRUE) ? ' checked="checked"' : '';
+			return ($input === 'value') ? ' checked="checked"' : '';
 		}
 
-		return ($input === (string) $value) ? ' checked="checked"' : '';
+		return ($default === TRUE) ? ' checked="checked"' : '';
 	}
 }
 
diff --git a/system/helpers/string_helper.php b/system/helpers/string_helper.php
index 637835160..3138a04b3 100644
--- a/system/helpers/string_helper.php
+++ b/system/helpers/string_helper.php
@@ -270,7 +270,7 @@ if ( ! function_exists('alternator'))
 	 * @param	string (as many parameters as needed)
 	 * @return	string
 	 */
-	function alternator($args)
+	function alternator()
 	{
 		static $i;
 
@@ -279,6 +279,7 @@ if ( ! function_exists('alternator'))
 			$i = 0;
 			return '';
 		}
+
 		$args = func_get_args();
 		return $args[($i++ % count($args))];
 	}
diff --git a/system/libraries/Email.php b/system/libraries/Email.php
index ebff7567a..034586ac9 100644
--- a/system/libraries/Email.php
+++ b/system/libraries/Email.php
@@ -1469,6 +1469,20 @@ class CI_Email {
 	 */
 	protected function _prep_quoted_printable($str)
 	{
+		// ASCII code numbers for "safe" characters that can always be
+		// used literally, without encoding, as described in RFC 2049.
+		// http://www.ietf.org/rfc/rfc2049.txt
+		static $ascii_safe_chars = array(
+			// ' (  )   +   ,   -   .   /   :   =   ?
+			39, 40, 41, 43, 44, 45, 46, 47, 58, 61, 63,
+			// numbers
+			48, 49, 50, 51, 52, 53, 54, 55, 56, 57,
+			// upper-case letters
+			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,
+			// lower-case letters
+			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
+		);
+
 		// We are intentionally wrapping so mail servers will encode characters
 		// properly and MUAs will behave, so {unwrap} must go!
 		$str = str_replace(array('{unwrap}', '{/unwrap}'), '', $str);
@@ -1516,14 +1530,25 @@ class CI_Email {
 				$ascii = ord($char);
 
 				// Convert spaces and tabs but only if it's the end of the line
-				if ($i === ($length - 1) && ($ascii === 32 OR $ascii === 9))
+				if ($ascii === 32 OR $ascii === 9)
 				{
-					$char = $escape.sprintf('%02s', dechex($ascii));
+					if ($i === ($length - 1))
+					{
+						$char = $escape.sprintf('%02s', dechex($ascii));
+					}
 				}
-				elseif ($ascii === 61) // encode = signs
+				// DO NOT move this below the $ascii_safe_chars line!
+				//
+				// = (equals) signs are allowed by RFC2049, but must be encoded
+				// as they are the encoding delimiter!
+				elseif ($ascii === 61)
 				{
 					$char = $escape.strtoupper(sprintf('%02s', dechex($ascii)));  // =3D
 				}
+				elseif ( ! in_array($ascii, $ascii_safe_chars, TRUE))
+				{
+					$char = $escape.strtoupper(sprintf('%02s', dechex($ascii)));
+				}
 
 				// If we're at the character limit, add the line to the output,
 				// reset our temp variable, and keep on chuggin'
diff --git a/system/libraries/Encryption.php b/system/libraries/Encryption.php
index f3e039881..151ce8dec 100644
--- a/system/libraries/Encryption.php
+++ b/system/libraries/Encryption.php
@@ -337,6 +337,11 @@ class CI_Encryption {
 	 */
 	public function create_key($length)
 	{
+		if (function_exists('random_bytes'))
+		{
+			return random_bytes((int) $length);
+		}
+
 		return ($this->_driver === 'mcrypt')
 			? mcrypt_create_iv($length, MCRYPT_DEV_URANDOM)
 			: openssl_random_pseudo_bytes($length);
diff --git a/system/libraries/Form_validation.php b/system/libraries/Form_validation.php
index a158225ee..c2212585d 100644
--- a/system/libraries/Form_validation.php
+++ b/system/libraries/Form_validation.php
@@ -415,12 +415,9 @@ class CI_Form_validation {
 	 */
 	public function run($group = '')
 	{
-		// Do we even have any data to process?  Mm?
-		$validation_array = empty($this->validation_data) ? $_POST : $this->validation_data;
-		if (count($validation_array) === 0)
-		{
-			return FALSE;
-		}
+		$validation_array = empty($this->validation_data)
+			? $_POST
+			: $this->validation_data;
 
 		// Does the _field_data array containing the validation rules exist?
 		// If not, we look to see if they were assigned via a config file
diff --git a/system/libraries/Session/Session_driver.php b/system/libraries/Session/Session_driver.php
index 47376da5b..64b4bb511 100644
--- a/system/libraries/Session/Session_driver.php
+++ b/system/libraries/Session/Session_driver.php
@@ -74,6 +74,18 @@ abstract class CI_Session_driver implements SessionHandlerInterface {
 	 */
 	protected $_session_id;
 
+	/**
+	 * Success and failure return values
+	 *
+	 * Necessary due to a bug in all PHP 5 versions where return values
+	 * from userspace handlers are not handled properly. PHP 7 fixes the
+	 * bug, so we need to return different values depending on the version.
+	 *
+	 * @see	https://wiki.php.net/rfc/session.user.return-value
+	 * @var	mixed
+	 */
+	protected $_success, $_failure;
+
 	// ------------------------------------------------------------------------
 
 	/**
@@ -85,6 +97,17 @@ abstract class CI_Session_driver implements SessionHandlerInterface {
 	public function __construct(&$params)
 	{
 		$this->_config =& $params;
+
+		if (is_php('7'))
+		{
+			$this->_success = TRUE;
+			$this->_failure = FALSE;
+		}
+		else
+		{
+			$this->_success = 0;
+			$this->_failure = -1;
+		}
 	}
 
 	// ------------------------------------------------------------------------
diff --git a/system/libraries/Session/drivers/Session_database_driver.php b/system/libraries/Session/drivers/Session_database_driver.php
index 72b39d12d..40a358fb8 100644
--- a/system/libraries/Session/drivers/Session_database_driver.php
+++ b/system/libraries/Session/drivers/Session_database_driver.php
@@ -125,9 +125,12 @@ class CI_Session_database_driver extends CI_Session_driver implements SessionHan
 	 */
 	public function open($save_path, $name)
 	{
-		return empty($this->_db->conn_id)
-			? (bool) $this->_db->db_connect()
-			: TRUE;
+		if (empty($this->_db->conn_id) && ! $this->_db->db_connect())
+		{
+			return $this->_failure;
+		}
+
+		return $this->_success;
 	}
 
 	// ------------------------------------------------------------------------
@@ -201,7 +204,7 @@ class CI_Session_database_driver extends CI_Session_driver implements SessionHan
 		{
 			if ( ! $this->_release_lock() OR ! $this->_get_lock($session_id))
 			{
-				return FALSE;
+				return $this->_failure;
 			}
 
 			$this->_row_exists = FALSE;
@@ -209,7 +212,7 @@ class CI_Session_database_driver extends CI_Session_driver implements SessionHan
 		}
 		elseif ($this->_lock === FALSE)
 		{
-			return FALSE;
+			return $this->_failure;
 		}
 
 		if ($this->_row_exists === FALSE)
@@ -224,10 +227,11 @@ class CI_Session_database_driver extends CI_Session_driver implements SessionHan
 			if ($this->_db->insert($this->_config['save_path'], $insert_data))
 			{
 				$this->_fingerprint = md5($session_data);
-				return $this->_row_exists = TRUE;
+				$this->_row_exists = TRUE;
+				return $this->_success;
 			}
 
-			return FALSE;
+			return $this->_failure;
 		}
 
 		$this->_db->where('id', $session_id);
@@ -247,10 +251,10 @@ class CI_Session_database_driver extends CI_Session_driver implements SessionHan
 		if ($this->_db->update($this->_config['save_path'], $update_data))
 		{
 			$this->_fingerprint = md5($session_data);
-			return TRUE;
+			return $this->_success;
 		}
 
-		return FALSE;
+		return $this->_failure;
 	}
 
 	// ------------------------------------------------------------------------
@@ -264,9 +268,9 @@ class CI_Session_database_driver extends CI_Session_driver implements SessionHan
 	 */
 	public function close()
 	{
-		return ($this->_lock)
-			? $this->_release_lock()
-			: TRUE;
+		return ($this->_lock && ! $this->_release_lock())
+			? $this->_failure
+			: $this->_success;
 	}
 
 	// ------------------------------------------------------------------------
@@ -289,12 +293,19 @@ class CI_Session_database_driver extends CI_Session_driver implements SessionHan
 				$this->_db->where('ip_address', $_SERVER['REMOTE_ADDR']);
 			}
 
-			return $this->_db->delete($this->_config['save_path'])
-				? ($this->close() && $this->_cookie_destroy())
-				: FALSE;
+			if ( ! $this->_db->delete($this->_config['save_path']))
+			{
+				return $this->_failure;
+			}
+		}
+
+		if ($this->close())
+		{
+			$this->_cookie_destroy();
+			return $this->_success;
 		}
 
-		return ($this->close() && $this->_cookie_destroy());
+		return $this->_failure;
 	}
 
 	// ------------------------------------------------------------------------
@@ -309,7 +320,9 @@ class CI_Session_database_driver extends CI_Session_driver implements SessionHan
 	 */
 	public function gc($maxlifetime)
 	{
-		return $this->_db->delete($this->_config['save_path'], 'timestamp < '.(time() - $maxlifetime));
+		return ($this->_db->delete($this->_config['save_path'], 'timestamp < '.(time() - $maxlifetime)))
+			? $this->_success
+			: $this->_failure;
 	}
 
 	// ------------------------------------------------------------------------
@@ -390,4 +403,4 @@ class CI_Session_database_driver extends CI_Session_driver implements SessionHan
 		return parent::_release_lock();
 	}
 
-}
+}
\ No newline at end of file
diff --git a/system/libraries/Session/drivers/Session_files_driver.php b/system/libraries/Session/drivers/Session_files_driver.php
index 45da91c46..f0f055f87 100644
--- a/system/libraries/Session/drivers/Session_files_driver.php
+++ b/system/libraries/Session/drivers/Session_files_driver.php
@@ -129,7 +129,7 @@ class CI_Session_files_driver extends CI_Session_driver implements SessionHandle
 			.$name // we'll use the session cookie name as a prefix to avoid collisions
 			.($this->_config['match_ip'] ? md5($_SERVER['REMOTE_ADDR']) : '');
 
-		return TRUE;
+		return $this->_success;
 	}
 
 	// ------------------------------------------------------------------------
@@ -156,13 +156,13 @@ class CI_Session_files_driver extends CI_Session_driver implements SessionHandle
 				if (($this->_file_handle = fopen($this->_file_path.$session_id, 'w+b')) === FALSE)
 				{
 					log_message('error', "Session: File '".$this->_file_path.$session_id."' doesn't exist and cannot be created.");
-					return FALSE;
+					return $this->_failure;
 				}
 			}
 			elseif (($this->_file_handle = fopen($this->_file_path.$session_id, 'r+b')) === FALSE)
 			{
 				log_message('error', "Session: Unable to open file '".$this->_file_path.$session_id."'.");
-				return FALSE;
+				return $this->_failure;
 			}
 
 			if (flock($this->_file_handle, LOCK_EX) === FALSE)
@@ -170,7 +170,7 @@ class CI_Session_files_driver extends CI_Session_driver implements SessionHandle
 				log_message('error', "Session: Unable to obtain lock for file '".$this->_file_path.$session_id."'.");
 				fclose($this->_file_handle);
 				$this->_file_handle = NULL;
-				return FALSE;
+				return $this->_failure;
 			}
 
 			// Needed by write() to detect session_regenerate_id() calls
@@ -183,6 +183,12 @@ class CI_Session_files_driver extends CI_Session_driver implements SessionHandle
 				return '';
 			}
 		}
+		// We shouldn't need this, but apparently we do ...
+		// See https://github.com/bcit-ci/CodeIgniter/issues/4039
+		elseif ($this->_file_handler === FALSE)
+		{
+			return $this->_failure;
+		}
 		else
 		{
 			rewind($this->_file_handle);
@@ -220,18 +226,18 @@ class CI_Session_files_driver extends CI_Session_driver implements SessionHandle
 		// and we need to close the old handle and open a new one
 		if ($session_id !== $this->_session_id && ( ! $this->close() OR $this->read($session_id) === FALSE))
 		{
-			return FALSE;
+			return $this->_failure;
 		}
 
 		if ( ! is_resource($this->_file_handle))
 		{
-			return FALSE;
+			return $this->_failure;
 		}
 		elseif ($this->_fingerprint === md5($session_data))
 		{
-			return ($this->_file_new)
-				? TRUE
-				: touch($this->_file_path.$session_id);
+			return ( ! $this->_file_new && ! touch($this->_file_path.$session_id))
+				? $this->_failure
+				: $this->_success;
 		}
 
 		if ( ! $this->_file_new)
@@ -254,12 +260,12 @@ class CI_Session_files_driver extends CI_Session_driver implements SessionHandle
 			{
 				$this->_fingerprint = md5(substr($session_data, 0, $written));
 				log_message('error', 'Session: Unable to write data.');
-				return FALSE;
+				return $this->_failure;
 			}
 		}
 
 		$this->_fingerprint = md5($session_data);
-		return TRUE;
+		return $this->_success;
 	}
 
 	// ------------------------------------------------------------------------
@@ -279,10 +285,9 @@ class CI_Session_files_driver extends CI_Session_driver implements SessionHandle
 			fclose($this->_file_handle);
 
 			$this->_file_handle = $this->_file_new = $this->_session_id = NULL;
-			return TRUE;
 		}
 
-		return TRUE;
+		return $this->_success;
 	}
 
 	// ------------------------------------------------------------------------
@@ -299,19 +304,31 @@ class CI_Session_files_driver extends CI_Session_driver implements SessionHandle
 	{
 		if ($this->close())
 		{
-			return file_exists($this->_file_path.$session_id)
-				? (unlink($this->_file_path.$session_id) && $this->_cookie_destroy())
-				: TRUE;
+			if (file_exists($this->_file_path.$session_id))
+			{
+				$this->_cookie_destroy();
+				return unlink($this->_file_path.$session_id)
+					? $this->_success
+					: $this->_failure;
+			}
+
+			return $this->_success;
 		}
 		elseif ($this->_file_path !== NULL)
 		{
 			clearstatcache();
-			return file_exists($this->_file_path.$session_id)
-				? (unlink($this->_file_path.$session_id) && $this->_cookie_destroy())
-				: TRUE;
+			if (file_exists($this->_file_path.$session_id))
+			{
+				$this->_cookie_destroy();
+				return unlink($this->_file_path.$session_id)
+					? $this->_success
+					: $this->_failure;
+			}
+
+			return $this->_success;
 		}
 
-		return FALSE;
+		return $this->_failure;
 	}
 
 	// ------------------------------------------------------------------------
@@ -329,7 +346,7 @@ class CI_Session_files_driver extends CI_Session_driver implements SessionHandle
 		if ( ! is_dir($this->_config['save_path']) OR ($directory = opendir($this->_config['save_path'])) === FALSE)
 		{
 			log_message('debug', "Session: Garbage collector couldn't list files under directory '".$this->_config['save_path']."'.");
-			return FALSE;
+			return $this->_failure;
 		}
 
 		$ts = time() - $maxlifetime;
@@ -356,7 +373,7 @@ class CI_Session_files_driver extends CI_Session_driver implements SessionHandle
 
 		closedir($directory);
 
-		return TRUE;
+		return $this->_success;
 	}
 
-}
+}
\ No newline at end of file
diff --git a/system/libraries/Session/drivers/Session_memcached_driver.php b/system/libraries/Session/drivers/Session_memcached_driver.php
index 97b860588..760239dfb 100644
--- a/system/libraries/Session/drivers/Session_memcached_driver.php
+++ b/system/libraries/Session/drivers/Session_memcached_driver.php
@@ -117,7 +117,7 @@ class CI_Session_memcached_driver extends CI_Session_driver implements SessionHa
 		{
 			$this->_memcached = NULL;
 			log_message('error', 'Session: Invalid Memcached save path format: '.$this->_config['save_path']);
-			return FALSE;
+			return $this->_failure;
 		}
 
 		foreach ($matches as $match)
@@ -142,10 +142,10 @@ class CI_Session_memcached_driver extends CI_Session_driver implements SessionHa
 		if (empty($server_list))
 		{
 			log_message('error', 'Session: Memcached server pool is empty.');
-			return FALSE;
+			return $this->_failure;
 		}
 
-		return TRUE;
+		return $this->_success;
 	}
 
 	// ------------------------------------------------------------------------
@@ -170,7 +170,7 @@ class CI_Session_memcached_driver extends CI_Session_driver implements SessionHa
 			return $session_data;
 		}
 
-		return FALSE;
+		return $this->_failure;
 	}
 
 	// ------------------------------------------------------------------------
@@ -188,14 +188,14 @@ class CI_Session_memcached_driver extends CI_Session_driver implements SessionHa
 	{
 		if ( ! isset($this->_memcached))
 		{
-			return FALSE;
+			return $this->_failure;
 		}
 		// Was the ID regenerated?
 		elseif ($session_id !== $this->_session_id)
 		{
 			if ( ! $this->_release_lock() OR ! $this->_get_lock($session_id))
 			{
-				return FALSE;
+				return $this->_failure;
 			}
 
 			$this->_fingerprint = md5('');
@@ -210,16 +210,18 @@ class CI_Session_memcached_driver extends CI_Session_driver implements SessionHa
 				if ($this->_memcached->set($this->_key_prefix.$session_id, $session_data, $this->_config['expiration']))
 				{
 					$this->_fingerprint = $fingerprint;
-					return TRUE;
+					return $this->_success;
 				}
 
-				return FALSE;
+				return $this->_failure;
 			}
 
-			return $this->_memcached->touch($this->_key_prefix.$session_id, $this->_config['expiration']);
+			return $this->_memcached->touch($this->_key_prefix.$session_id, $this->_config['expiration'])
+				? $this->_success
+				: $this->_failure;
 		}
 
-		return FALSE;
+		return $this->_failure;
 	}
 
 	// ------------------------------------------------------------------------
@@ -238,14 +240,14 @@ class CI_Session_memcached_driver extends CI_Session_driver implements SessionHa
 			isset($this->_lock_key) && $this->_memcached->delete($this->_lock_key);
 			if ( ! $this->_memcached->quit())
 			{
-				return FALSE;
+				return $this->_failure;
 			}
 
 			$this->_memcached = NULL;
-			return TRUE;
+			return $this->_success;
 		}
 
-		return FALSE;
+		return $this->_failure;
 	}
 
 	// ------------------------------------------------------------------------
@@ -263,10 +265,11 @@ class CI_Session_memcached_driver extends CI_Session_driver implements SessionHa
 		if (isset($this->_memcached, $this->_lock_key))
 		{
 			$this->_memcached->delete($this->_key_prefix.$session_id);
-			return $this->_cookie_destroy();
+			$this->_cookie_destroy();
+			return $this->_success;
 		}
 
-		return FALSE;
+		return $this->_failure;
 	}
 
 	// ------------------------------------------------------------------------
@@ -282,7 +285,7 @@ class CI_Session_memcached_driver extends CI_Session_driver implements SessionHa
 	public function gc($maxlifetime)
 	{
 		// Not necessary, Memcached takes care of that.
-		return TRUE;
+		return $this->_success;
 	}
 
 	// ------------------------------------------------------------------------
@@ -299,7 +302,9 @@ class CI_Session_memcached_driver extends CI_Session_driver implements SessionHa
 	{
 		if (isset($this->_lock_key))
 		{
-			return $this->_memcached->replace($this->_lock_key, time(), 300);
+			return ($this->_memcached->replace($this->_lock_key, time(), 300))
+				? $this->_success
+				: $this->_failure;
 		}
 
 		// 30 attempts to obtain a lock, in case another request already has it
@@ -316,7 +321,7 @@ class CI_Session_memcached_driver extends CI_Session_driver implements SessionHa
 			if ( ! $this->_memcached->set($lock_key, time(), 300))
 			{
 				log_message('error', 'Session: Error while trying to obtain lock for '.$this->_key_prefix.$session_id);
-				return FALSE;
+				return $this->_failure;
 			}
 
 			$this->_lock_key = $lock_key;
@@ -327,11 +332,11 @@ class CI_Session_memcached_driver extends CI_Session_driver implements SessionHa
 		if ($attempt === 30)
 		{
 			log_message('error', 'Session: Unable to obtain lock for '.$this->_key_prefix.$session_id.' after 30 attempts, aborting.');
-			return FALSE;
+			return $this->_failure;
 		}
 
 		$this->_lock = TRUE;
-		return TRUE;
+		return $this->_success;
 	}
 
 	// ------------------------------------------------------------------------
diff --git a/system/libraries/Session/drivers/Session_redis_driver.php b/system/libraries/Session/drivers/Session_redis_driver.php
index 4fa6c28b3..2395df1b5 100644
--- a/system/libraries/Session/drivers/Session_redis_driver.php
+++ b/system/libraries/Session/drivers/Session_redis_driver.php
@@ -136,7 +136,7 @@ class CI_Session_redis_driver extends CI_Session_driver implements SessionHandle
 	{
 		if (empty($this->_config['save_path']))
 		{
-			return FALSE;
+			return $this->_failure;
 		}
 
 		$redis = new Redis();
@@ -161,7 +161,7 @@ class CI_Session_redis_driver extends CI_Session_driver implements SessionHandle
 			else
 			{
 				$this->_redis = $redis;
-				return TRUE;
+				return $this->_success;
 			}
 		}
 		else
@@ -169,7 +169,7 @@ class CI_Session_redis_driver extends CI_Session_driver implements SessionHandle
 			log_message('error', 'Session: Unable to connect to Redis with the configured settings.');
 		}
 
-		return FALSE;
+		return $this->_failure;
 	}
 
 	// ------------------------------------------------------------------------
@@ -194,7 +194,7 @@ class CI_Session_redis_driver extends CI_Session_driver implements SessionHandle
 			return $session_data;
 		}
 
-		return FALSE;
+		return $this->_failure;
 	}
 
 	// ------------------------------------------------------------------------
@@ -212,14 +212,14 @@ class CI_Session_redis_driver extends CI_Session_driver implements SessionHandle
 	{
 		if ( ! isset($this->_redis))
 		{
-			return FALSE;
+			return $this->_failure;
 		}
 		// Was the ID regenerated?
 		elseif ($session_id !== $this->_session_id)
 		{
 			if ( ! $this->_release_lock() OR ! $this->_get_lock($session_id))
 			{
-				return FALSE;
+				return $this->_failure;
 			}
 
 			$this->_fingerprint = md5('');
@@ -234,16 +234,18 @@ class CI_Session_redis_driver extends CI_Session_driver implements SessionHandle
 				if ($this->_redis->set($this->_key_prefix.$session_id, $session_data, $this->_config['expiration']))
 				{
 					$this->_fingerprint = $fingerprint;
-					return TRUE;
+					return $this->_success;
 				}
 
-				return FALSE;
+				return $this->_failure;
 			}
 
-			return $this->_redis->setTimeout($this->_key_prefix.$session_id, $this->_config['expiration']);
+			return ($this->_redis->setTimeout($this->_key_prefix.$session_id, $this->_config['expiration']))
+				? $this->_success
+				: $this->_failure;
 		}
 
-		return FALSE;
+		return $this->_failure;
 	}
 
 	// ------------------------------------------------------------------------
@@ -265,7 +267,7 @@ class CI_Session_redis_driver extends CI_Session_driver implements SessionHandle
 					isset($this->_lock_key) && $this->_redis->delete($this->_lock_key);
 					if ( ! $this->_redis->close())
 					{
-						return FALSE;
+						return $this->_failure;
 					}
 				}
 			}
@@ -275,10 +277,10 @@ class CI_Session_redis_driver extends CI_Session_driver implements SessionHandle
 			}
 
 			$this->_redis = NULL;
-			return TRUE;
+			return $this->_success;
 		}
 
-		return TRUE;
+		return $this->_success;
 	}
 
 	// ------------------------------------------------------------------------
@@ -300,10 +302,11 @@ class CI_Session_redis_driver extends CI_Session_driver implements SessionHandle
 				log_message('debug', 'Session: Redis::delete() expected to return 1, got '.var_export($result, TRUE).' instead.');
 			}
 
-			return $this->_cookie_destroy();
+			$this->_cookie_destroy();
+			return $this->_success;
 		}
 
-		return FALSE;
+		return $this->_failure;
 	}
 
 	// ------------------------------------------------------------------------
@@ -319,7 +322,7 @@ class CI_Session_redis_driver extends CI_Session_driver implements SessionHandle
 	public function gc($maxlifetime)
 	{
 		// Not necessary, Redis takes care of that.
-		return TRUE;
+		return $this->_success;
 	}
 
 	// ------------------------------------------------------------------------