Turns out when you grab an OS mutex, you need to be careful about when and where
things are scheduled!
I've confirmed that I could fairly reliably get a deadlock (1 in 100 times ish) before this, and I cannot get a deadlock after this (after 1000+ runs).
Closes#11200
Some people have requested this, and I think it's quite useful to have
documentation for the compiler libraries. libnative and libgreen are
self-explanatory I think.
Of the 8 static mutexes that are currently in-use by the compiler and its
libraries, 4 of them are currently used for one-time initialization. The
unforunate side effect of using a static mutex is that the mutex is leaked.
This primitive should provide the basis for efficiently keeping track of
one-time initialization as well as ensuring that it does not leak the internal
mutex that is used.
I have chosen to put this in libstd because libstd is currently making use of a
static initialization mutex (rt::local_ptr), but I can also see a more refined
version of this type being suitable to initialize FFI bindings (such as
initializing LLVM and initializing winsock networking on windows). I also intend
on adding "helper threads" to libnative, and those will greatly benefit from a
simple "once" primitive rather than always reinventing the wheel by using
mutexes and bools.
I would much rather see this primitive built on a mutex that blocks green
threads appropriately, but that does not exist at this time, so it does not
belong outside of `std::unstable`.
The old `rtio-processes` run-pass test is now moved into libstd's `io::process` module, and all process and TCP tests are now run with `iotest!` (both a native and a green version are tested).
All TCP networking on windows is provided by `ws2_32` which is apparently very similar to unix networking (hurray!).
Move the tests into libstd, use the `iotest!` macro to test both native and uv
bindings, and use the cloexec trick to figure out when the child process fails
in exec.
This patch changes `result::collect` (and adds a new `option::collect`) from creating a `~[T]` to take an `Iterator`. This makes the function much more flexible, and may replace the need for #10989.
This patch is a little more complicated than it needs to be because of #11084. Once that is fixed we can replace the `CollectIterator` with a `Scan` iterator.
It also fixes a test warning.
This commit uniforms the short title of modules provided by libstd,
in order to make their roles more explicit when glancing at the index.
Signed-off-by: Luca Bruno <lucab@debian.org>
