/* --------------------------------------------------------------------
* Push a response into the return queue and eventually tickle the
* receiver.
*/
int
send_blocking_resp_internal(
blocking_child * c,
blocking_pipe_header * resp
)
{
size_t qhead;
int empty;
/* >>>> ACCESS LOCKING STARTS >>>> */
wait_for_sem(c->accesslock, NULL);
empty = ensure_workresp_empty_slot(c);
qhead = c->head_response;
c->responses[qhead % c->responses_alloc] = resp;
c->head_response = 1 + qhead;
tickle_sem(c->accesslock);
/* <<<< ACCESS LOCKING ENDS <<<< */
/* queue consumer wake-up notification */
if (empty)
{
# ifdef WORK_PIPE
write(c->resp_write_pipe, "", 1);
# else
tickle_sem(c->responses_pending);
# endif
}
return 0;
}
int
send_blocking_req_internal(
blocking_child * c,
blocking_pipe_header * hdr,
void * data
)
{
blocking_pipe_header * threadcopy;
size_t payload_octets;
REQUIRE(hdr != NULL);
REQUIRE(data != NULL);
DEBUG_REQUIRE(BLOCKING_REQ_MAGIC == hdr->magic_sig);
if (hdr->octets <= sizeof(*hdr))
return 1; /* failure */
payload_octets = hdr->octets - sizeof(*hdr);
ensure_workitems_empty_slot(c);
if (NULL == c->thread_ref) {
ensure_workresp_empty_slot(c);
start_blocking_thread(c);
}
threadcopy = emalloc(hdr->octets);
memcpy(threadcopy, hdr, sizeof(*hdr));
memcpy((char *)threadcopy + sizeof(*hdr), data, payload_octets);
return queue_req_pointer(c, threadcopy);
}
int
send_blocking_resp_internal(
blocking_child * c,
blocking_pipe_header * resp
)
{
ensure_workresp_empty_slot(c);
c->responses[c->next_response] = resp;
c->next_response = (1 + c->next_response) % c->responses_alloc;
#ifdef USE_WORK_PIPE
IGNORE(write(c->resp_write_pipe, "", 1));
#else
sem_post(c->blocking_response_ready);
#endif
return 0;
}