/*
* ipc_finish() -
*
* Locks and destroys the semaphore set and message queue if called
* in the daemonized queue runner. If force isn't given, it will
* only do so if the archive queue is empty after locking the set
* and draining the message queue.
*/
int
ipc_finish(bool force)
{
if (ipc_creator)
{
if (!force)
{
/*
* We are the creator of the semaphore set, so if this isn't
* a force operation, we lock it first, poll the message queue
* and check that we have an empty queue.
*/
if (ipc_lock() < 0)
{
fprintf(stderr, "semop() failed in ipc_finish(): %s\n",
strerror(errno));
return -1;
}
if (ipc_poll(false) < 0)
return -1;
if (archive_queue_head != NULL)
{
if (ipc_unlock() < 0)
{
fprintf(stderr, "semop() failed in ipc_finish(): %s\n",
strerror(errno));
return -1;
}
return 1;
}
}
/*
* At this point, we are either forced to stop or we have a lock
* and the queue is empty.
*/
if (msgctl(msgid, IPC_RMID, NULL) < 0)
{
fprintf(stderr, "msgctl() failed in ipc_finish(): %s\n",
strerror(errno));
semctl(semid, 0, IPC_RMID);
return -1;
}
if (semctl(semid, 0, IPC_RMID) < 0)
{
fprintf(stderr, "semctl() failed in ipc_finish(): %s\n",
strerror(errno));
return -1;
}
}
return 0;
}
/*
* ipc_send_code() -
*
* Support function for ipc_send_term() and ipc_send_resume().
*/
static int
ipc_send_code(char *archive_dir, int code)
{
struct {
long mtype;
char mtext[1];
} msg;
if (ipc_generate_keys(archive_dir) < 0)
return -1;
if ((semid = semget(semkey, 0, 0)) < 0)
{
if (!opt_quiet)
fprintf(stderr, "no logshipper daemon running\n");
return 2;
}
if (ipc_lock() < 0)
return -1;
if ((msgid = msgget(msgkey, 0)) < 0)
{
fprintf(stderr, "msgget() failed in ipc_send_code(): %s\n",
strerror(errno));
ipc_unlock();
return -1;
}
msg.mtype = (long)code;
if (msgsnd(msgid, &msg, 0, 0) < 0)
{
fprintf(stderr, "msgsnd() failed in ipc_send_code(): %s\n",
strerror(errno));
ipc_unlock();
return -1;
}
return ipc_unlock();
}
/*
* freeque() wakes up waiters on the sender and receiver waiting queue,
* removes the message queue from message queue ID IDR, and cleans up all the
* messages associated with this queue.
*
* msg_ids.rw_mutex (writer) and the spinlock for this message queue are held
* before freeque() is called. msg_ids.rw_mutex remains locked on exit.
*/
static void freeque(struct ipc_namespace *ns, struct kern_ipc_perm *ipcp)
{
struct list_head *tmp;
struct msg_queue *msq = container_of(ipcp, struct msg_queue, q_perm);
expunge_all(msq, -EIDRM);
ss_wakeup(&msq->q_senders, 1);
msg_rmid(ns, msq);
msg_unlock(msq);
tmp = msq->q_messages.next;
while (tmp != &msq->q_messages) {
struct msg_msg *msg = list_entry(tmp, struct msg_msg, m_list);
tmp = tmp->next;
atomic_dec(&ns->msg_hdrs);
free_msg(msg);
}
atomic_sub(msq->q_cbytes, &ns->msg_bytes);
security_msg_queue_free(msq);
ipc_lock_by_ptr(&msq->q_perm);
ipc_rcu_putref(msq);
ipc_unlock(&msq->q_perm);
}
static inline void sem_putref(struct sem_array *sma)
{
ipc_lock_by_ptr(&sma->sem_perm);
ipc_rcu_putref(sma);
ipc_unlock(&(sma)->sem_perm);
}
static inline void sem_getref_and_unlock(struct sem_array *sma)
{
ipc_rcu_getref(sma);
ipc_unlock(&(sma)->sem_perm);
}
