This roughly doubles our test coverage of the bridges.c module.
* ADD new testing module, .../src/test/test_bridges.c.
* CHANGE a few function declarations from `static` to `STATIC`.
* CHANGE one function in transports.c, transport_get_by_name(), to be
mockable.
* CLOSES#25425: https://bugs.torproject.org/25425
This module doesn't actually need to mock the libevent mainloop at
all: it can just use the regular mainloop that the test environment
sets up.
Part of ticket 23750.
This change makes cpuworker and test_workqueue no longer need to
include event2/event.h. Now workqueue.c needs to include it, but
that is at least somewhat logical here.
There's now no difference in these tests w.r.t. the C or Rust: both
fail miserably (well, Rust fails with nice descriptive errors, and C
gives you a traceback, because, well, C).
The DoS potential is slightly higher in C now due to some differences to the
Rust code, see the C_RUST_DIFFERS tags in src/rust/protover/tests/protover.rs.
Also, the comment about "failing at the splitting stage" in Rust wasn't true,
since when we split, we ignore empty chunks (e.g. "1--1" parses into
"(1,None),(None,1)" and "None" can't be parsed into an integer).
Finally, the comment about "Rust seems to experience an internal error" is only
true in debug mode, where u32s are bounds-checked at runtime. In release mode,
code expressing the equivalent of this test will error with
`Err(ProtoverError::Unparseable)` because 4294967295 is too large.
Previously, if "Link=1-5" was supported, and you asked protover_all_supported()
(or protover::all_supported() in Rust) if it supported "Link=3-999", the C
version would return "Link=3-999" and the Rust would return "Link=6-999". These
both behave the same now, i.e. both return "Link=6-999".
There's now no difference in these tests w.r.t. the C or Rust: both
fail miserably (well, Rust fails with nice descriptive errors, and C
gives you a traceback, because, well, C).
The DoS potential is slightly higher in C now due to some differences to the
Rust code, see the C_RUST_DIFFERS tags in src/rust/protover/tests/protover.rs.
Also, the comment about "failing at the splitting stage" in Rust wasn't true,
since when we split, we ignore empty chunks (e.g. "1--1" parses into
"(1,None),(None,1)" and "None" can't be parsed into an integer).
Finally, the comment about "Rust seems to experience an internal error" is only
true in debug mode, where u32s are bounds-checked at runtime. In release mode,
code expressing the equivalent of this test will error with
`Err(ProtoverError::Unparseable)` because 4294967295 is too large.
Previously, if "Link=1-5" was supported, and you asked protover_all_supported()
(or protover::all_supported() in Rust) if it supported "Link=3-999", the C
version would return "Link=3-999" and the Rust would return "Link=6-999". These
both behave the same now, i.e. both return "Link=6-999".
These tests handle incoming and outgoing cells on a three-hop
circuit, and make sure that the crypto works end-to-end. They don't
yet test spec conformance, leaky-pipe, or various error cases.
