Threadsafe Vector class for C++

by

This is difficult because of algorithms.

Suppose you wrapped vector so that all its member functions are serialised using a mutex, like Java synchronized methods. Then concurrent calls to std::remove on that vector still wouldn’t be safe, because they rely on looking at the vector and changing it based on what they see.

So your LockingVector would need to specialize every template in the standard algorithms, to lock around the whole thing. But then other algorithms like std::remove_if would be calling user-defined code under the lock. Doing this silently behind the scenes is a recipe for locking inversion as soon as someone starts creating vectors of objects which themselves internally take locks around all their methods.

In answer to your actual question: sorry, no, I don’t know of one. For a quick test of the kind you need, I recommend that you start out with:

template <typename T>
class LockedVector {
    private:
    SomeKindOfLock lock;
    std::vector<T> vec;
};

Then drop it in as a replacement container, and start implementing member functions (and member typedefs, and operators) until it compiles. You’ll notice pretty quickly if any of your code is using iterators on the vector in a way which simply cannot be made thread-safe from the inside out, and if need be you can temporarily change the calling code in those cases to lock the vector via public methods.

More Related Contents:

  1. Multithreading program stuck in optimized mode but runs normally in -O0
  2. unordered_map thread safety
  3. STL vector and thread-safety
  4. Thread safety of std::map for read-only operations
  5. How to implement a unmanaged thread-safe collection when I get this error: is not supported when compiling with /clr
  6. thread safety of MPI send using threads created with std::async
  7. Why is volatile not considered useful in multithreaded C or C++ programming?
  8. Simple example of threading in C++
  9. Concurrency: Atomic and volatile in C++11 memory model
  10. Programmatically find the number of cores on a machine
  11. Does const mean thread-safe in C++11?
  12. Using stdlib’s rand() from multiple threads
  13. Lock-free Progress Guarantees in a circular buffer queue
  14. Are C++ Reads and Writes of an int Atomic?
  15. How to efficiently display OpenCV video in Qt?
  16. What’s the difference between “static” and “dynamic” schedule in OpenMP?
  17. Precise thread sleep needed. Max 1ms error
  18. What is the difference between packaged_task and async
  19. Thread safe lazy construction of a singleton in C++
  20. C++11 Thread safety of Random number generators
  21. C++ Thread-Safe Map
  22. c++ work queues with blocking
  23. How to correctly read an Interlocked.Increment’ed int field?
  24. Is it safe to use a boolean flag to stop a thread from running in C#
  25. ConcurrentDictionary Pitfall – Are delegates factories from GetOrAdd and AddOrUpdate synchronized?
  26. Is C++ static member variable initialization thread-safe?
  27. Thread safety on readonly static field initialisation
  28. Why there are three unexpected worker threads when a Win32 console application starts up? [duplicate]
  29. Is a memory barrier required to read a value that is atomically modified?
  30. C++11 Implementation of Spinlock using header “

Leave a Comment