If a newly spawned thread called getThreadId or getThreadHandle before
the spawning thread finished saving the thread handle, then the
handle/id would be used uninitialized. This would cause the threading
tests to fail since isCurrentThread would return false, and if Minetest
is built with C++11 support the std::thread object pointer would be
dereferenced while ininitialized, causing a segmentation fault.
This fixes the issue by using a mutex to force the spawned thread to
wait for the spawning thread to finish initializing the thread object.
An alternative way to handle this would be to also set the thread
handle/id in the started thread but this wouldn't work for C++11
builds because there's no way to get the partially constructed object.
The initial problem was that mutex_auto_lock.h tries to use std::unique_lock<std::mutex>
despite mutex.h not using C++11's std::mutex on Windows. The problem here is the mismatch
between C++11 usage conditions of the two headers. This commit moves the decision logic
to threads.h and makes sure mutex.h, mutex_auto_lock.h and event.h all use the same features.
For several years now, the lua script lock has been completely broken.
This commit fixes the main issue (creation of a temporary rather than
scoped object), and fixes a subsequent deadlock issue caused by
nested script API calls by adding support for recursive mutexes.
* Rename everything.
* Strip J prefix.
* Change UpperCamelCase functions to lowerCamelCase.
* Remove global (!) semaphore count mutex on OSX.
* Remove semaphore count getter (unused, unsafe, depended on internal
API functions on Windows, and used a hack on OSX).
* Add `Atomic<type>`.
* Make `Thread` handle thread names.
* Add support for C++11 multi-threading.
* Combine pthread and win32 sources.
* Remove `ThreadStarted` (unused, unneeded).
* Move some includes from the headers to the sources.
* Move all of `Event` into its header (allows inlining with no new includes).
* Make `Event` use `Semaphore` (except on Windows).
* Move some porting functions into `Thread`.
* Integrate logging with `Thread`.
* Add threading test.
