This class represents queues of specified size capacity. The push operation may be blocked if the capacity is full.
See Thread::Queue for an example of how a Thread::SizedQueue works.
static VALUE
rb_szqueue_initialize(VALUE self, VALUE vmax)
{
long max;
struct rb_szqueue *sq = szqueue_ptr(self);
max = NUM2LONG(vmax);
if (max <= 0) {
rb_raise(rb_eArgError, "queue size must be positive");
}
RB_OBJ_WRITE(self, szqueue_list(sq), ary_buf_new());
ccan_list_head_init(szqueue_waitq(sq));
ccan_list_head_init(szqueue_pushq(sq));
sq->max = max;
return self;
}
Creates a fixed-length queue with a maximum size of max.
static VALUE
rb_szqueue_clear(VALUE self)
{
struct rb_szqueue *sq = szqueue_ptr(self);
rb_ary_clear(check_array(self, sq->q.que));
wakeup_all(szqueue_pushq(sq));
return self;
}
Removes all objects from the queue.
static VALUE
rb_szqueue_close(VALUE self)
{
if (!queue_closed_p(self)) {
struct rb_szqueue *sq = szqueue_ptr(self);
FL_SET(self, QUEUE_CLOSED);
wakeup_all(szqueue_waitq(sq));
wakeup_all(szqueue_pushq(sq));
}
return self;
}
Similar to Thread::Queue#close.
The difference is behavior with waiting enqueuing threads.
If there are waiting enqueuing threads, they are interrupted by raising ClosedQueueError(‘queue closed’).
static VALUE
rb_szqueue_empty_p(VALUE self)
{
struct rb_szqueue *sq = szqueue_ptr(self);
return RBOOL(queue_length(self, &sq->q) == 0);
}
Returns true if the queue is empty.
static VALUE
rb_queue_freeze(VALUE self)
{
rb_raise(rb_eTypeError, "cannot freeze " "%+"PRIsVALUE, self);
UNREACHABLE_RETURN(self);
}
The queue can’t be frozen, so this method raises an exception:
Thread::Queue.new.freeze # Raises TypeError (cannot freeze #<Thread::Queue:0x...>)
static VALUE
rb_szqueue_length(VALUE self)
{
struct rb_szqueue *sq = szqueue_ptr(self);
return LONG2NUM(queue_length(self, &sq->q));
}
Returns the length of the queue.
static VALUE
rb_szqueue_max_get(VALUE self)
{
return LONG2NUM(szqueue_ptr(self)->max);
}
Returns the maximum size of the queue.
static VALUE
rb_szqueue_max_set(VALUE self, VALUE vmax)
{
long max = NUM2LONG(vmax);
long diff = 0;
struct rb_szqueue *sq = szqueue_ptr(self);
if (max <= 0) {
rb_raise(rb_eArgError, "queue size must be positive");
}
if (max > sq->max) {
diff = max - sq->max;
}
sq->max = max;
sync_wakeup(szqueue_pushq(sq), diff);
return vmax;
}
Sets the maximum size of the queue to the given number.
static VALUE
rb_szqueue_num_waiting(VALUE self)
{
struct rb_szqueue *sq = szqueue_ptr(self);
return INT2NUM(sq->q.num_waiting + sq->num_waiting_push);
}
Returns the number of threads waiting on the queue.
# File tmp/rubies/ruby-3.3.0/thread_sync.rb, line 36
def pop(non_block = false, timeout: nil)
if non_block && timeout
raise ArgumentError, "can't set a timeout if non_block is enabled"
end
Primitive.rb_szqueue_pop(non_block, timeout)
end
Retrieves data from the queue.
If the queue is empty, the calling thread is suspended until data is pushed onto the queue. If non_block is true, the thread isn’t suspended, and ThreadError is raised.
If timeout seconds have passed and no data is available nil is returned. If timeout is 0 it returns immediately.
# File tmp/rubies/ruby-3.3.0/thread_sync.rb, line 59
def push(object, non_block = false, timeout: nil)
if non_block && timeout
raise ArgumentError, "can't set a timeout if non_block is enabled"
end
Primitive.rb_szqueue_push(object, non_block, timeout)
end
Pushes object to the queue.
If there is no space left in the queue, waits until space becomes available, unless non_block is true. If non_block is true, the thread isn’t suspended, and ThreadError is raised.
If timeout seconds have passed and no space is available nil is returned. If timeout is 0 it returns immediately. Otherwise it returns self.