void
ipc_mqueue_move(
ipc_mqueue_t dest,
ipc_mqueue_t source,
const ipc_port_t port)
{
ipc_kmsg_queue_t oldq, newq;
ipc_thread_queue_t blockedq;
ipc_kmsg_t kmsg, next;
ipc_thread_t th;
oldq = &source->imq_messages;
newq = &dest->imq_messages;
blockedq = &dest->imq_threads;
for (kmsg = ipc_kmsg_queue_first(oldq);
kmsg != IKM_NULL; kmsg = next) {
next = ipc_kmsg_queue_next(oldq, kmsg);
/* only move messages sent to port */
if (kmsg->ikm_header.msgh_remote_port != (mach_port_t) port)
continue;
ipc_kmsg_rmqueue(oldq, kmsg);
/* before adding kmsg to newq, check for a blocked receiver */
while ((th = ipc_thread_dequeue(blockedq)) != ITH_NULL) {
assert(ipc_kmsg_queue_empty(newq));
thread_go(th);
/* check if the receiver can handle the message */
if (kmsg->ikm_header.msgh_size <= th->ith_msize) {
th->ith_state = MACH_MSG_SUCCESS;
th->ith_kmsg = kmsg;
th->ith_seqno = port->ip_seqno++;
goto next_kmsg;
}
th->ith_state = MACH_RCV_TOO_LARGE;
th->ith_msize = kmsg->ikm_header.msgh_size;
}
/* didn't find a receiver to handle the message */
ipc_kmsg_enqueue(newq, kmsg);
next_kmsg:;
}
}
void
ipc_mqueue_move(
ipc_mqueue_t dest,
ipc_mqueue_t source,
ipc_port_t port)
{
ipc_kmsg_queue_t oldq, newq;
ipc_thread_queue_t blockedq;
ipc_kmsg_t kmsg, next;
ipc_thread_t th;
oldq = &source->imq_messages;
newq = &dest->imq_messages;
blockedq = &dest->imq_threads;
for (kmsg = ipc_kmsg_queue_first(oldq); kmsg != IKM_NULL; kmsg = next) {
next = ipc_kmsg_queue_next(oldq, kmsg);
/* only move messages sent to port */
if (kmsg->ikm_header.msgh_remote_port != (mach_port_t) port)
continue;
ipc_kmsg_rmqueue(oldq, kmsg);
/* before adding kmsg to newq, check for a blocked receiver */
if ((th = ipc_thread_dequeue(blockedq)) != ITH_NULL) {
assert(ipc_kmsg_queue_empty(newq));
/*
* Got a receiver. Hand the receiver the message
* and process the next one.
*/
th->ith_state = MACH_MSG_SUCCESS;
th->ith_kmsg = kmsg;
th->ith_seqno = port->ip_seqno++;
thread_go(th);
} else {
/* didn't find a receiver; enqueue the message */
ipc_kmsg_enqueue(newq, kmsg);
}
}
}
