Disable core dump for SIGHUP signal

I'm trying to disable core dumps being generated for individual signals in my application.

ulimit -c 0 wont work in my case, since it needs to be executed before application start and will completely disable core dumps for all signals.

Is it possible to make such an exception for a single signal or at least disable core dump generation for a certain amount of time (eg. during sending the SIGHUP signal)?

#include <setjmp.h>
#include <signal.h>
#include <stdlib.h>
#include <sys/resource.h>
#include <unistd.h>

static sigjmp_buf sigjmp;
static void sighup_handler(int signo) {
    siglongjmp(&sigjmp, signo);
}

int main(int argc, char **argv) {
    struct sigaction sighup_action = {
        .sa_handler = &sighup_handler,
        .sa_flags = SA_RESETHAND,
    };
    sigset_t sigset;
    int signo;

    sigemptyset(&sighup_action.sa_mask);
    sigaddset(&sighup_action.sa_mask, SIGHUP);
    sigprocmask(SIG_BLOCK, &sighup_action.sa_mask, &sigset);
    sigaction(SIGHUP, &sighup_action, NULL);
    signo = sigsetjmp(&sigjmp, 1);
    if (signo) {
        struct rlimit rl = { .rlim_cur = 0, .rlim_max = 0 };
        setrlimit(RLIMIT_CORE, &rl);
        sigprocmask(SIG_SETMASK, &sigset, NULL);
        kill(getpid(), signo);
        abort();  /* just in case */
        _exit(128 | signo);
    }
    sigprocmask(SIG_SETMASK, &sigset, NULL);

    pause(); /* or whatever the rest of your program does */
}

You can install a signal handler which sets RLIMIT_CORE to 0, then proceeds with the default signal action. If you use SA_RESETHAND, the default signal handler is automatically reinstalled right before the signal handler is run. However, setrlimit is not async-signal-safe, so we should not call it from inside a signal handler, hence using siglongjmp to return to normal code and performing it there.