+ +
+

Compatibility Functions

+

CodeIgniter provides a set of compatibility functions that enable +you to use functions what are otherwise natively available in PHP, +but only in higher versions or depending on a certain extension.

+

Being custom implementations, these functions will also have some +set of dependencies on their own, but are still useful if your +PHP setup doesn’t offer them natively.

+
+

Note

+

Much like the common functions, the +compatibility functions are always available, as long as +their dependencies are met.

+
+ +
+

Password Hashing

+

This set of compatibility functions offers a “backport” of PHP’s +standard Password Hashing extension +that is otherwise available only since PHP 5.5.

+
+

Dependencies

+
    +
  • PHP 5.3.7
    • +
  • CRYPT_BLOWFISH support for crypt()
    • +
+
+
+

Constants

+
    +
  • PASSWORD_BCRYPT
    • +
  • PASSWORD_DEFAULT
    • +
+
+
+

Function reference

+
+
+password_get_info($hash)
+
+++ + + + + + + + +
Parameters:
    +
  • $hash (string) – Password hash
    • +
+
Returns:

Information about the hashed password

+
Return type:

array

+
+

For more information, please refer to the PHP manual for +password_get_info().

+
+ +
+
+password_hash($password, $algo[, $options = array()])
+
+++ + + + + + + + +
Parameters:
    +
  • $password (string) – Plain-text password
    • +
  • $algo (int) – Hashing algorithm
    • +
  • $options (array) – Hashing options
    • +
+
Returns:

Hashed password or FALSE on failure

+
Return type:

string

+
+

For more information, please refer to the PHP manual for +password_hash().

+
+

Note

+

Unless you provide your own (and valid) salt, this function +has a further dependency on an available CSPRNG source. Each +of the following would satisfy that: +- mcrypt_create_iv() with MCRYPT_DEV_URANDOM +- openssl_random_pseudo_bytes() +- /dev/arandom +- /dev/urandom

+
+
+ +
+
+password_needs_rehash()
+
+++ + + + + + + + +
Parameters:
    +
  • $hash (string) – Password hash
    • +
  • $algo (int) – Hashing algorithm
    • +
  • $options (array) – Hashing options
    • +
+
Returns:

TRUE if the hash should be rehashed to match the given algorithm and options, FALSE otherwise

+
Return type:

bool

+
+

For more information, please refer to the PHP manual for +password_needs_rehash().

+
+ +
+
+password_verify($password, $hash)
+
+++ + + + + + + + +
Parameters:
    +
  • $password (string) – Plain-text password
    • +
  • $hash (string) – Password hash
    • +
+
Returns:

TRUE if the password matches the hash, FALSE if not

+
Return type:

bool

+
+

For more information, please refer to the PHP manual for +password_verify().

+
+ +
+
+
+

Hash (Message Digest)

+

This compatibility layer contains backports for the hash_equals() +and hash_pbkdf2() functions, which otherwise require PHP 5.6 and/or +PHP 5.5 respectively.

+
+

Dependencies

+
    +
  • None
    • +
+
+
+

Function reference

+
+
+hash_equals($known_string, $user_string)
+
+++ + + + + + + + +
Parameters:
    +
  • $known_string (string) – Known string
    • +
  • $user_string (string) – User-supplied string
    • +
+
Returns:

TRUE if the strings match, FALSE otherwise

+
Return type:

string

+
+

For more information, please refer to the PHP manual for +hash_equals().

+
+ +
+
+hash_pbkdf2($algo, $password, $salt, $iterations[, $length = 0[, $raw_output = FALSE]])
+
+++ + + + + + + + +
Parameters:
    +
  • $algo (string) – Hashing algorithm
    • +
  • $password (string) – Password
    • +
  • $salt (string) – Hash salt
    • +
  • $iterations (int) – Number of iterations to perform during derivation
    • +
  • $length (int) – Output string length
    • +
  • $raw_output (bool) – Whether to return raw binary data
    • +
+
Returns:

Password-derived key or FALSE on failure

+
Return type:

string

+
+

For more information, please refer to the PHP manual for +hash_pbkdf2().

+
+ +
+
+
+

Multibyte String

+

This set of compatibility functions offers limited support for PHP’s +Multibyte String extension. Because of +the limited alternative solutions, only a few functions are available.

+
+

Note

+

When a character set parameter is ommited, +$config['charset'] will be used.

+
+
+

Dependencies

+ +
+

Important

+

This dependency is optional and these functions will +always be declared. If iconv is not available, they WILL +fall-back to their non-mbstring versions.

+
+
+

Important

+

Where a character set is supplied, it must be +supported by iconv and in a format that it recognizes.

+
+
+

Note

+

For you own dependency check on the actual mbstring +extension, use the MB_ENABLED constant.

+
+
+
+

Function reference

+
+
+mb_strlen($str[, $encoding = NULL])
+
+++ + + + + + + + +
Parameters:
    +
  • $str (string) – Input string
    • +
  • $encoding (string) – Character set
    • +
+
Returns:

Number of characters in the input string or FALSE on failure

+
Return type:

string

+
+

For more information, please refer to the PHP manual for +mb_strlen().

+
+ +
+
+mb_strpos($haystack, $needle[, $offset = 0[, $encoding = NULL]])
+
+++ + + + + + + + +
Parameters:
    +
  • $haystack (string) – String to search in
    • +
  • $needle (string) – Part of string to search for
    • +
  • $offset (int) – Search offset
    • +
  • $encoding (string) – Character set
    • +
+
Returns:

Numeric character position of where $needle was found or FALSE if not found

+
Return type:

mixed

+
+

For more information, please refer to the PHP manual for +mb_strpos().

+
+ +
+
+mb_substr($str, $start[, $length = NULL[, $encoding = NULL]])
+
+++ + + + + + + + +
Parameters:
    +
  • $str (string) – Input string
    • +
  • $start (int) – Position of first character
    • +
  • $length (int) – Maximum number of characters
    • +
  • $encoding (string) – Character set
    • +
+
Returns:

Portion of $str specified by $start and $length or FALSE on failure

+
Return type:

string

+
+

For more information, please refer to the PHP manual for +mb_substr().

+
+ +
+
+
+

Standard Functions

+

This set of compatibility functions offers support for a few +standard functions in PHP that otherwise require a newer PHP version.

+
+

Dependencies

+
    +
  • None
    • +
+
+
+

Function reference

+
+
+array_column(array $array, $column_key[, $index_key = NULL])
+
+++ + + + + + + + +
Parameters:
    +
  • $array (array) – Array to fetch results from
    • +
  • $column_key (mixed) – Key of the column to return values from
    • +
  • $index_key (mixed) – Key to use for the returned values
    • +
+
Returns:

An array of values representing a single column from the input array

+
Return type:

array

+
+

For more information, please refer to the PHP manual for +array_column().

+
+ +
+
+hex2bin($data)
+
+++ + + + + + + + +
Parameters:
    +
  • $data (array) – Hexadecimal representation of data
    • +
+
Returns:

Binary representation of the given data

+
Return type:

string

+
+

For more information, please refer to the PHP manual for hex2bin().

+
+ +
+
+
+ + +