/*! Check if buffer is empty for a given consumer.
*
* Checks in this function are taken from <tt>OMSbuff_read()</tt> and not
* optimized
*
* \param Consumer to be checked.
* \return 1 if buffer is empty, 0 if not.
* \return -1 on error.
*
* \see OMSbuff_read
* */
int OMSbuff_isempty(OMSConsumer * cons)
{
OMSSlot *last_read;
OMSSlot *next;
OMSbuff_lock(cons->buffer);
OMSbuff_shm_refresh(cons->buffer);
last_read = OMStoSlot(cons->buffer, cons->last_read_pos);
next = &cons->buffer->slots[cons->read_pos];
if (!next->refs || (next->slot_seq < cons->last_seq)) {
// added some slots?
if (last_read && cons->buffer->slots[last_read->next].refs
&& (cons->buffer->slots[last_read->next].slot_seq >
cons->last_seq))
RETURN(0);
else
RETURN(1);
} else if (last_read
&& (cons->buffer->slots[last_read->next].slot_seq <
next->slot_seq))
RETURN(0);
OMSbuff_unlock(cons->buffer);
return 0;
}
double OMSbuff_nextts(OMSConsumer *cons)
{
OMSSlot *last_read;
OMSSlot *next;
OMSbuff_lock(cons->buffer);
OMSbuff_shm_refresh(cons->buffer);
last_read = OMStoSlot(cons->buffer, cons->last_read_pos);
next = &cons->buffer->slots[cons->read_pos];
if ( !next->refs || (next->slot_seq < cons->last_seq) ) {
// added some slots?
if ( last_read && cons->buffer->slots[last_read->next].refs && (cons->buffer->slots[last_read->next].slot_seq > cons->last_seq) )
next = &cons->buffer->slots[last_read->next];
else {
OMSbuff_unlock(cons->buffer);
return -1;
}
} else if (last_read && ( cons->buffer->slots[last_read->next].slot_seq < next->slot_seq ) )
next = &cons->buffer->slots[last_read->next];
OMSbuff_unlock(cons->buffer);
return next->timestamp;
}
/* ! move current read position
*
* \return 1 on error, 0 otherwise
* */
int32 OMSbuff_gotreader(OMSConsumer *cons)
{
OMSSlot *last_read;
OMSSlot *next;
OMSbuff_lock(cons->buffer);
if (OMSbuff_shm_refresh(cons->buffer))
RETURN_ERR
last_read = OMStoSlot(cons->buffer, cons->last_read_pos);
next = &cons->buffer->slots[cons->read_pos];
if ( !next->refs || (next->slot_seq < cons->last_seq) ) {
// added some slots?
if ( last_read && cons->buffer->slots[last_read->next].refs && (cons->buffer->slots[last_read->next].slot_seq > cons->last_seq) )
next = &cons->buffer->slots[last_read->next];
else
RETURN_ERR
} else if (last_read && ( cons->buffer->slots[last_read->next].slot_seq < next->slot_seq ) )
/* ! Add and return a new consumer reference to the buffer,
* \return NULL if an error occurs*/
OMSConsumer *OMSbuff_ref(OMSBuffer *buffer)
{
OMSConsumer *cons;
ptrdiff_t i;
if (!buffer) return NULL;
if ((cons = (OMSConsumer *)malloc(sizeof(OMSConsumer))) == NULL )
return NULL;
cons->last_read_pos = -1;// OMStoSlotPtr(buffer, NULL);
cons->buffer = buffer;
cons->frames=0;
cons->firstts = -1;
OMSbuff_lock(buffer);
// cons->read_pos = buffer->slots[buffer->control->write_pos].next;
// cons->last_seq = buffer->slots[buffer->control->write_pos].slot_seq;
cons->read_pos = buffer->control->valid_read_pos; // buffer->slots[buffer->control->valid_read_pos].next;
cons->last_seq = 0; // buffer->slots[buffer->control->valid_read_pos].slot_seq;
if (buffer->slots[cons->read_pos].slot_seq) {
for (i=cons->read_pos; i!=buffer->control->write_pos; i=buffer->slots[i].next)
buffer->slots[i].refs++;
buffer->slots[i].refs++;
}
printf("ref at position %d (write_pos @ %d)\n", cons->read_pos, buffer->control->write_pos);
buffer->control->refs++;
// if ( msync(buffer->control, sizeof(OMSControl), MS_SYNC) )
// printf("*** control msync error\n");
OMSbuff_unlock(buffer);
fnc_log(FNC_LOG_DEBUG, "Buffer ref (%d)\n", buffer->control->refs);
return cons;
}