The `struct thread **ref` that the thread code takes is written to and
needs to stay valid over the lifetime of a thread. This does not hold
up if thread pointers are directly put in a `vector` since adding items
to a `vector` may reallocate the entire array. The thread code would
then write to a now-invalid `ref`, potentially corrupting entirely
unrelated data.
This should be extremely rare to trigger in practice since we only use
one c-ares channel, which will likely only ever use one fd, so the
vector is never resized. That said, c-ares using only one fd is just
plain fragile luck.
Either way, fix this by creating a resolver_fd tracking struct, and
clean up the code while we're at it.
Signed-off-by: David Lamparter <equinox@opensourcerouting.org>
The current code passes an address of a local variable to `thread_add_read`
which stores it into `thread->ref` by the lib. The next time the thread
callback is executed, the lib stores NULL into the `thread->ref` which
means it writes into some random memory on the stack.
To fix this, we should pass a pointer to the vector entry to the lib.
Signed-off-by: Igor Ryzhov <iryzhov@nfware.com>
Our "true" libraries (i.e. not modules) don't invoke neither
FRR_DAEMON_INFO nor FRR_MODULE_SETUP, hence XREF_SETUP isn't invoked
either. Invoke it directly to get things working.
Signed-off-by: David Lamparter <equinox@diac24.net>
And again for the name. Why on earth would we centralize this, just so
people can forget to update it?
Signed-off-by: David Lamparter <equinox@diac24.net>
There is really no reason to not put this in the cmd_node.
And while we're add it, rename from pointless ".func" to ".config_write".
[v2: fix forgotten ldpd config_write]
Signed-off-by: David Lamparter <equinox@diac24.net>
The only nodes that have this as 0 don't have a "->func" anyway, so the
entire thing is really just pointless.
Signed-off-by: David Lamparter <equinox@diac24.net>
To keep the calling code agnostic of the DNS resolver libary used, pass
a strerror-style string instead of a status code that would need extra
handling.
Signed-off-by: David Lamparter <equinox@diac24.net>
libc-ares doesn't do IP literals, so we have to do that before running
off to do DNS. Since this isn't BMP specific, move to lib/ so NHRP can
benefit too.
Signed-off-by: David Lamparter <equinox@diac24.net>
The callback itself might want to reschedule the resolver, so it is
useful to clear out the callback field before making the call instead of
after.
Signed-off-by: David Lamparter <equinox@diac24.net>
