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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
     enqueued).  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