protected function doIncrement($key, $offset, $initial, $expire)
{
$ttl = $this->ttl($expire);
/*
* APC has apc_inc & apc_dec, which work great. However, they don't
* allow for a TTL to be set.
* I could use apc_inc & apc_dec & then do a touch, but touch also
* doesn't have an APC implementation & needs a get & cas. That would
* be 2 operations + CAS.
* Instead, I'll just do a get, implement the increase or decrease in
* PHP, then CAS the new value = 1 operation + CAS.
*/
$value = $this->get($key, $token);
if ($value === false) {
// don't even set initial value, it's already expired...
if ($ttl < 0) {
return $initial;
}
// no need for locking - set will do that
$success = $this->add($key, $initial, $ttl);
return $success ? $initial : false;
}
if (!is_numeric($value) || $value < 0) {
return false;
}
$value += $offset;
// value can never be lower than 0
$value = max(0, $value);
// negative TTLs don't always seem to properly treat the key as deleted
if ($ttl < 0) {
$success = $this->delete($key);
return $success ? $value : false;
}
// no need for locking - cas will do that
$success = $this->cas($token, $key, $value, $ttl);
return $success ? $value : false;
}
