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.
The source used a hodge-podge of different combinations of different
macros to check for linux: 'linux', '__linux', '__linux__'.
As '__linux__' is standard (Posix), and the others are not, the source
now uniformly uses __linux__. If either linux or __linux are defined,
it is made sure that __linux__ is defined as well.
- Fix some incompatibilities with obscure platforms (AIX and WinCE)
- Clean up Thread class interface
- Add m_ prefix to private member variables
- Simplify platform-dependent logic, reducing preprocessor
conditional clauses and improving readibility
- Add Thread class documentation
- Add warning log level
- Change debug_log_level setting to enumeration string
- Map Irrlicht log events to MT log events
- Encapsulate log_* functions and global variables into a class, Logger
- Unify dstream with standard logging mechanism
- Unify core.debug() with standard core.log() script API
Commit
e4bff8be94c0db4f94e63ad448d0eeb869ccdbbd - Clean up threading
by @ShadowNinja has broken the OSX build.
Including things inside a namespace isn't good.
Also fixes#3124.
* 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.
