Use an Apache handler after declining another

Question

I have two handlers to be accessed. My motive is to use the second handler if the first handler returns DECLINED.

I have tried various combinations of SetHandler, AddHandler and AddType but none has worked as overriding takes place in all of these combinations.

Is there any method in Apache to use more than one handler without overriding?

Answer 1

If the first handler (returning DECLINED) is yours, you can hook it by specifying its successor(s), e.g.:

static void my_register_hooks(apr_pool_t *p)
{
 static const char * const succs[] = { "mod_running_after.c", NULL };

 ...
 ap_hook_handler(my_handler, NULL, succs, APR_HOOK_);
 ...
}

This works for any hook, also by specifying predecessor(s) instead of the above NULL.