class Thread::Mutex
Thread::Mutex
implements a simple semaphore that can be used to coordinate access to shared data from multiple concurrent threads.
Example:
semaphore = Thread::Mutex.new a = Thread.new { semaphore.synchronize { # access shared resource } } b = Thread.new { semaphore.synchronize { # access shared resource } }
Public Class Methods
Creates a new Mutex
static VALUE mutex_initialize(VALUE self) { return self; }
Public Instance Methods
Attempts to grab the lock and waits if it isn’t available. Raises ThreadError
if mutex
was locked by the current thread.
VALUE rb_mutex_lock(VALUE self) { return do_mutex_lock(self, 1); }
Returns true
if this lock is currently held by some thread.
VALUE rb_mutex_locked_p(VALUE self) { rb_mutex_t *mutex = mutex_ptr(self); return RBOOL(mutex->fiber); }
Returns true
if this lock is currently held by current thread.
VALUE rb_mutex_owned_p(VALUE self) { rb_fiber_t *fiber = GET_EC()->fiber_ptr; rb_mutex_t *mutex = mutex_ptr(self); return mutex_owned_p(fiber, mutex); }
Releases the lock and sleeps timeout
seconds if it is given and non-nil or forever. Raises ThreadError
if mutex
wasn’t locked by the current thread.
When the thread is next woken up, it will attempt to reacquire the lock.
Note that this method can wakeup without explicit Thread#wakeup
call. For example, receiving signal and so on.
Returns the slept time in seconds if woken up, or nil
if timed out.
static VALUE mutex_sleep(int argc, VALUE *argv, VALUE self) { VALUE timeout; timeout = rb_check_arity(argc, 0, 1) ? argv[0] : Qnil; return rb_mutex_sleep(self, timeout); }
Obtains a lock, runs the block, and releases the lock when the block completes. See the example under Thread::Mutex
.
static VALUE rb_mutex_synchronize_m(VALUE self) { if (!rb_block_given_p()) { rb_raise(rb_eThreadError, "must be called with a block"); } return rb_mutex_synchronize(self, rb_yield, Qundef); }
Attempts to obtain the lock and returns immediately. Returns true
if the lock was granted.
VALUE rb_mutex_trylock(VALUE self) { rb_mutex_t *mutex = mutex_ptr(self); if (mutex->fiber == 0) { RUBY_DEBUG_LOG("%p ok", mutex); rb_fiber_t *fiber = GET_EC()->fiber_ptr; rb_thread_t *th = GET_THREAD(); mutex->fiber = fiber; mutex_locked(th, self); return Qtrue; } else { RUBY_DEBUG_LOG("%p ng", mutex); return Qfalse; } }
Releases the lock. Raises ThreadError
if mutex
wasn’t locked by the current thread.
VALUE rb_mutex_unlock(VALUE self) { const char *err; rb_mutex_t *mutex = mutex_ptr(self); rb_thread_t *th = GET_THREAD(); err = rb_mutex_unlock_th(mutex, th, GET_EC()->fiber_ptr); if (err) rb_raise(rb_eThreadError, "%s", err); return self; }