sources/liblfds/queue/queue_new.c

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#include "queue_internal.h"
#if defined(HLX_BUILD_WITH_PARALLEL_THREADING)

extern hlx_api gl_api;



/****************************************************************************/
int queue_new( struct queue_state **qs, atom_t number_elements )
{
  int
    rv = 0;

  struct queue_element
    *qe[QUEUE_PAC_SIZE];

  /* TRD : number_elements can be any value in its range */

  *qs = (struct queue_state *) gl_api.aligned_malloc_entry( sizeof(struct queue_state), ALIGN_DOUBLE_POINTER );

  if( *qs != 0 )
  {
    /* TRD : the size of the freelist is the size of the queue (+1 for the leading dummy element, which is hidden from the caller) */
    freelist_new( &(*qs)->fs, number_elements+1, queue_internal_freelist_init_function, 0 );

    if( (*qs)->fs != 0 )
    {
      queue_internal_new_element_from_freelist( *qs, qe, 0 );
      (*qs)->enqueue[QUEUE_POINTER] = (*qs)->dequeue[QUEUE_POINTER] = qe[QUEUE_POINTER];
      (*qs)->aba_counter = 0;
      rv = 1;
    }

    if( (*qs)->fs == 0 )
    {
      gl_api.aligned_free_entry( *qs );
      *qs = 0;
    }
  }

  return( rv );
}





/****************************************************************************/
#pragma warning( disable : 4100 )

int queue_internal_freelist_init_function( void **user_data, void *user_state )
{
  int
    rv = 0;

  *user_data = gl_api.aligned_malloc_entry( sizeof(struct queue_element), ALIGN_DOUBLE_POINTER );

  if( *user_data != 0 )
    rv = 1;

  return( rv );
}

#pragma warning( default : 4100 )





/****************************************************************************/
void queue_internal_new_element_from_freelist( struct queue_state *qs, struct queue_element *qe[QUEUE_PAC_SIZE], void *user_data )
{
  struct freelist_element
    *fe;

  /* TRD : user_data can be any value in its range */

  qe[QUEUE_POINTER] = 0;

  freelist_pop( qs->fs, &fe );

  if( fe != 0 )
    queue_internal_init_element( qs, qe, fe, user_data );

  return;
}





/****************************************************************************/
void queue_internal_guaranteed_new_element_from_freelist( struct queue_state *qs, struct queue_element *qe[QUEUE_PAC_SIZE], void *user_data )
{
  struct freelist_element
    *fe;

  /* TRD : user_data can be any value in its range */

  qe[QUEUE_POINTER] = 0;

  freelist_guaranteed_pop( qs->fs, &fe );

  if( fe != 0 )
    queue_internal_init_element( qs, qe, fe, user_data );

  return;
}





/****************************************************************************/
void queue_internal_init_element( struct queue_state *qs, struct queue_element *qe[QUEUE_PAC_SIZE], struct freelist_element *fe, void *user_data )
{
  /* TRD : user_data can be any value in its range */

  freelist_get_user_data_from_element( fe, (void **) &qe[QUEUE_POINTER] );
  qe[QUEUE_COUNTER] = (struct queue_element *) gl_api.atomic_incr_entry( (atom_t *) &qs->aba_counter );

  qe[QUEUE_POINTER]->next[QUEUE_POINTER] = 0;
  qe[QUEUE_POINTER]->next[QUEUE_COUNTER] = (struct queue_element *) gl_api.atomic_incr_entry( (atom_t *) &qs->aba_counter );

  qe[QUEUE_POINTER]->fe = fe;
  qe[QUEUE_POINTER]->user_data = user_data;

  return;
}

#endif /* !HLX_BUILD_WITH_PARALLEL_THREADING */