/* Registers 'hook' to be called when a process termination signal is raised.
* If 'run_at_exit' is true, 'hook' is also called during normal process
* termination, e.g. when exit() is called or when main() returns. */
void
fatal_signal_add_hook(void (*func)(void *aux), void *aux, bool run_at_exit)
{
fatal_signal_block();
assert(n_hooks < MAX_HOOKS);
hooks[n_hooks].func = func;
hooks[n_hooks].aux = aux;
hooks[n_hooks].run_at_exit = run_at_exit;
n_hooks++;
fatal_signal_unblock();
}
/* Unregisters 'file' from being unlinked when the program terminates via
* exit() or a fatal signal. */
void
fatal_signal_remove_file_to_unlink(const char *file)
{
size_t i;
fatal_signal_block();
for (i = 0; i < n_files; i++) {
if (!strcmp(files[i], file)) {
free(files[i]);
files[i] = files[--n_files];
break;
}
}
fatal_signal_unblock();
}
/* Registers 'file' to be unlinked when the program terminates via exit() or a
* fatal signal. */
void
fatal_signal_add_file_to_unlink(const char *file)
{
static bool added_hook = false;
if (!added_hook) {
added_hook = true;
fatal_signal_add_hook(unlink_files, NULL, true);
fatal_signal_add_hook(destroy_pipeline, NULL, true);
}
fatal_signal_block();
if (n_files >= max_files) {
files = x2nrealloc(files, &max_files, sizeof *files);
}
files[n_files++] = xstrdup(file);
fatal_signal_unblock();
}
int
main(int argc, char *argv[])
{
struct dhclient *cli;
int error;
set_program_name(argv[0]);
register_fault_handlers();
vlog_init();
parse_options(argc, argv);
argc -= optind;
argv += optind;
if (argc != 1) {
ofp_fatal(0, "exactly one non-option argument required; "
"use --help for help");
}
error = dhclient_create(argv[0], modify_dhcp_request, NULL, NULL, &cli);
if (error) {
ofp_fatal(error, "dhclient_create failed");
}
dhclient_init(cli, request_ip.s_addr);
fatal_signal_add_hook(release, cli, true);
for (;;) {
fatal_signal_block();
dhclient_run(cli);
if (dhclient_changed(cli)) {
dhclient_configure_netdev(cli);
if (update_resolv_conf) {
dhclient_update_resolv_conf(cli);
}
}
dhclient_wait(cli);
fatal_signal_unblock();
poll_block();
}
}