The tests previously assumed that the link handshake code would be
calling get_my_certs() -- when I changed it to call get_own_cert()
instead for the (case 2) 22460 fix, the tests failed, since the tls
connection wasn't really there.
This change makes us start mocking out the tor_tls_get_own_cert()
function too.
It also corrects the behavior of the mock_get_peer_cert() function
-- it should have been returning a newly allocated copy.
Previously, you needed to store the previous log severity in a local
variable, and it wasn't clear if you were allowed to call these
functions more than once.
This is a big-ish patch, but it's very straightforward. Under this
clang warning, we're not actually allowed to have a global variable
without a previous extern declaration for it. The cases where we
violated this rule fall into three roughly equal groups:
* Stuff that should have been static.
* Stuff that was global but where the extern was local to some
other C file.
* Stuff that was only global when built for the unit tests, that
needed a conditional extern in the headers.
The first two were IMO genuine problems; the last is a wart of how
we build tests.
An earlier version of these tests was broken; now they're a nicer,
more robust, more black-box set of tests. The key is to have each
test check a handshake message that is wrong in _one_ way.