WIP : [runtime] shutdown functions refactoring

[astrophysik]

shutdown functions refactoring

What's the problem

At this time shutdown functions are not called if we get an error in the network context. For example, a timeout or connection interruption does not cause the shutdown functions to be called.

Solution

Let's add function check_net_error() that will be called after pause and check for networking errors on the script resume to invoke shutdown_functions.

Also let's resume script in finish() if we get network error

Additions

1. Fix bug of second shutdown function call

<?php

/**
 * @kphp-required
 */
function at_finish0()
{
    fwrite(STDERR, "FINISHED 0\n");
}

/**
 * @kphp-required
 */
function at_finish1()
{
    fwrite(STDERR, "FINISHED 1\n");
    exit(0);
}

register_shutdown_function('at_finish0');
register_shutdown_function('at_finish1');
throw new Exception("example", 1);

2. Correct function 'check_tl()' so that it calls the shutdown function