Does PHP support long bit array?

Question

So I'm trying to work on a web service that deals with long bit arrays (100+ bits).

Can anyone suggest a class in PHP that deals with long bit arrays?

Answer 1

PHP doesn't support long bit arrays, you can use ordinary arrays and calculate proper offset as (this is sample for 32 bit architecture):

$array = [];
$bitToSet = 33;
setbit($array, $bitToSet);
print_r($array);

echo getbit($array, $bitToSet-1) . "\n";
echo getbit($array, $bitToSet) . "\n";
echo getbit($array, $bitToSet+2) . "\n";

function setbit(&$array, $bitNumber) {
    $arrayIdx = $bitNumber >> 5; // I suppose 32 bit int
    $bitIdx = $bitNumber & 0x1f;
    if (!isset($array[$arrayIdx])) $array[$arrayIdx] = 0;
    $array[$arrayIdx] = (1<<$bitIdx); 
}
function uRShift($a, $b) {
    if($b == 0) return $a;
    return ($a >> $b) & ~(1<<(8*PHP_INT_SIZE-1)>>($b-1));
}
function getbit(&$array, $bitNumber) {
    $arrayIdx = $bitNumber >> 5;
    $bitIdx = $bitNumber & 0x1f;
    if (!isset($array[$arrayIdx])) $array[$arrayIdx] = 0;
    return uRShift($array[$arrayIdx], $bitIdx)&1;
}

also you can check about GMP and BC Math, second not the best option anyway