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CK_RING_ENQUEUE_SPSC_... BSD Library Functions Manual CK_RING_ENQUEUE_SPSC_...

NAME
     ck_ring_enqueue_spsc_size -- enqueue pointer into bounded FIFO and	return
     size of buffer

LIBRARY
     Concurrency Kit (libck, -lck)

SYNOPSIS
     #include <ck_ring.h>

     bool
     ck_ring_enqueue_spsc_size(ck_ring_t *ring,	ck_ring_buffer_t *buffer,
	 void *entry, unsigned int *size);

DESCRIPTION
     The ck_ring_enqueue_spsc_size(3) function enqueues	the pointer entry into
     the bounded buffer	pointed	to by ring in FIFO fashion.  The buffer
     pointed to	by buffer must be unique to ring and point to an array of
     ck_ring_buffer_t of sufficient length (according to the power-of-2	ele-
     ments in the buffer).  The	decoupling of the ring from the	buffer serves
     to	address	use-cases involving multiple address spaces and	DMA, among
     others.  If you are on non-POSIX platforms	or wish	for strict compliance
     with C, then it is	recommended to pass a pointer of type void ** for
     entry.  This function is safe to call without locking for up to one con-
     current invocation	of ck_ring_dequeue_spsc(3).  This function provides
     wait-free progress	guarantees.

EXAMPLE
	   #include <ck_ring.h>

	   /* This ring	was previously initialized with	ck_ring_init. */
	   ck_ring_t ring;

	   /* The ring was initialized for 1023	elements. */
	   ck_ring_buffer_t buffer[1024];

	   void
	   enqueue(void)
	   {
		   void	*entry = some_object;
		   unsigned int	length;

		   /* Attempt to enqueue pointer to some_object	into buffer. */
		   if (ck_ring_enqueue_spsc(&ring, &buffer, &entry, &length) ==	false) {
			   /*
			    * The buffer was full and the enqueue operation
			    * has failed.
			    */
			   return;
		   }

		   /*
		    * If buffer	length was 100 items or	more at	the time entry was
		    * enqueued,	do something.
		    */
		   if (length >	100) {
			   do_something;
		   }

		   return;
	   }

RETURN VALUES
     The function returns true if the value of entry was successfully enqueued
     into ring.	 This function will return the number of items in ring with
     respect to	the linearization point	(the point in item that	entry is en-
     queued).  The function will return	false if the value of entry could not
     be	enqueued which only occurs if ring was full.

SEE ALSO
     ck_ring_init(3), ck_ring_dequeue_spmc(3), ck_ring_trydequeue_spmc(3),
     ck_ring_enqueue_spmc(3), ck_ring_enqueue_spmc_size(3),
     ck_ring_dequeue_spsc(3), ck_ring_enqueue_spsc(3), ck_ring_capacity(3),
     ck_ring_size(3)

     Additional	information available at http://concurrencykit.org/

				April 20, 2013

NAME | LIBRARY | SYNOPSIS | DESCRIPTION | EXAMPLE | RETURN VALUES | SEE ALSO

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