MyShaarli/application/Utils.php

46 lines
1.2 KiB
PHP

<?php
/**
* Shaarli utilities
*/
/**
* Returns the small hash of a string, using RFC 4648 base64url format
*
* Small hashes:
* - are unique (well, as unique as crc32, at last)
* - are always 6 characters long.
* - only use the following characters: a-z A-Z 0-9 - _ @
* - are NOT cryptographically secure (they CAN be forged)
*
* In Shaarli, they are used as a tinyurl-like link to individual entries,
* e.g. smallHash('20111006_131924') --> yZH23w
*/
function smallHash($text)
{
$t = rtrim(base64_encode(hash('crc32', $text, true)), '=');
return strtr($t, '+/', '-_');
}
/**
* Tells if a string start with a substring
*/
function startsWith($haystack, $needle, $case=true)
{
if ($case) {
return (strcmp(substr($haystack, 0, strlen($needle)), $needle) === 0);
}
return (strcasecmp(substr($haystack, 0, strlen($needle)), $needle) === 0);
}
/**
* Tells if a string ends with a substring
*/
function endsWith($haystack, $needle, $case=true)
{
if ($case) {
return (strcmp(substr($haystack, strlen($haystack) - strlen($needle)), $needle) === 0);
}
return (strcasecmp(substr($haystack, strlen($haystack) - strlen($needle)), $needle) === 0);
}
?>