wp_update_urls_to_https()

wp_update_urls_to_https(): bool

function wp_update_urls_to_https() {
	// Get current URL options.
	$orig_home    = get_option( 'home' );
	$orig_siteurl = get_option( 'siteurl' );

	// Get current URL options, replacing HTTP with HTTPS.
	$home    = str_replace( 'http://', 'https://', $orig_home );
	$siteurl = str_replace( 'http://', 'https://', $orig_siteurl );

	// Update the options.
	update_option( 'home', $home );
	update_option( 'siteurl', $siteurl );

	if ( ! wp_is_using_https() ) {
		/*
		 * If this did not result in the site recognizing HTTPS as being used,
		 * revert the change and return false.
		 */
		update_option( 'home', $orig_home );
		update_option( 'siteurl', $orig_siteurl );
		return false;
	}

	// Otherwise the URLs were successfully changed to use HTTPS.
	return true;
}