Function os_has_altstack_installed

wasm2c/wasm-rt-impl.c:168–177

#if WASM_RT_STACK_EXHAUSTION_HANDLER
static bool os_has_altstack_installed() {
  /* check for altstack already in place */
  stack_t ss;
  if (sigaltstack(NULL, &ss) != 0) {
    perror("os_has_altstack_installed: sigaltstack failed");
    abort();
  }

  return !(ss.ss_flags & SS_DISABLE);
}

/* These routines set up an altstack to handle SIGSEGV from stack overflow. */
static void os_allocate_and_install_altstack(void) {