wordpress: custom pagination with wpdb get_results

gistfile1.php

<?php

global $wpdb;

$sql = "
    SELECT   $wpdb->posts.* 
    FROM     $wpdb->posts
    WHERE    $wpdb->posts.post_status = 'publish'
    AND      $wpdb->posts.post_type = 'post'
    AND      $wpdb->posts.post_date < NOW()
    ORDER BY $wpdb->posts.post_date DESC
";

$current        = get_query_var( 'paged' ) ? intval( get_query_var( 'paged' ) ) : 1;
$post_per_page  = get_option( 'posts_per_page' );
$offset         = ( $current * $post_per_page ) - $post_per_page;
$all_results    = $wpdb->get_results( $wpdb->prepare( $sql ), OBJECT );
$total          = $wpdb->num_rows;
$result         = $wpdb->get_results( $wpdb->prepare( $sql . 'LIMIT %d, %d', $offset, $post_per_page ), OBJECT );

if ( $sql ) {
    global $post;

    foreach ( $sql as $post ) {
        setup_postdata( $post );

        // custom loop
    }

    $args = array(
        'base'    => add_query_arg( 'paged', '%#%' ),
        'total'   => ceil ( $total / $post_per_page ),
        'current' => $current
    );

    echo paginate_links( $args );
}