static pipe*
find_pipe(text* pipe_name, bool* created, bool only_check)
{
int i;
pipe *result = NULL;
*created = false;
for (i = 0; i < MAX_PIPES; i++)
{
if (pipes[i].is_valid &&
strncmp((char*)VARDATA(pipe_name), pipes[i].pipe_name, VARSIZE(pipe_name) - VARHDRSZ) == 0
&& (strlen(pipes[i].pipe_name) == (VARSIZE(pipe_name) - VARHDRSZ)))
{
/* check owner if non public pipe */
if (pipes[i].creator != NULL && pipes[i].uid != GetUserId())
{
LWLockRelease(shmem_lockid);
ereport(ERROR,
(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
errmsg("insufficient privilege"),
errdetail("Insufficient privilege to access pipe")));
}
return &pipes[i];
}
}
if (only_check)
return result;
for (i = 0; i < MAX_PIPES; i++)
if (!pipes[i].is_valid)
{
if (NULL != (pipes[i].pipe_name = ora_scstring(pipe_name)))
{
pipes[i].is_valid = true;
pipes[i].registered = false;
pipes[i].creator = NULL;
pipes[i].uid = -1;
pipes[i].count = 0;
pipes[i].limit = -1;
*created = true;
result = &pipes[i];
}
break;
}
return result;
}
static alert_event*
find_event(text *event_name, bool create, int *event_id)
{
int i;
for (i = 0; i < MAX_EVENTS;i++)
{
if (events[i].event_name != NULL && textcmpm(event_name,events[i].event_name) == 0)
{
if (event_id != NULL)
*event_id = i;
return &events[i];
}
}
if (create)
{
for (i=0; i < MAX_EVENTS; i++)
{
if (events[i].event_name == NULL)
{
events[i].event_name = ora_scstring(event_name);
events[i].max_receivers = 0;
events[i].receivers = NULL;
events[i].messages = NULL;
events[i].receivers_number = 0;
if (event_id != NULL)
*event_id = i;
return &events[i];
}
}
ereport(ERROR,
(errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED),
errmsg("event registeration error"),
errdetail("Too many registered events."),
errhint("There are too many collaborating sessions. Increase MAX_EVENTS in 'pipe.h'.")));
}
return NULL;
}
static void
create_message(text *event_name, text *message)
{
int event_id;
alert_event *ev;
message_item *msg_item = NULL;
int i,j,k;
find_event(event_name, false, &event_id);
/* process event only when any recipient exitsts */
if (NULL != (ev = find_event(event_name, false, &event_id)))
{
if (ev->receivers_number > 0)
{
msg_item = ev->messages;
while (msg_item != NULL)
{
if (msg_item->message == NULL && message == NULL)
return;
if (msg_item->message != NULL && message != NULL)
if (0 == textcmpm(message,msg_item->message))
return;
msg_item = msg_item->next_message;
}
msg_item = salloc(sizeof(message_item));
msg_item->receivers = salloc( ev->receivers_number*sizeof(int));
msg_item->receivers_number = ev->receivers_number;
if (message != NULL)
msg_item->message = ora_scstring(message);
else
msg_item->message = NULL;
msg_item->message_id = event_id;
for (i = j = 0; j < ev->max_receivers; j++)
{
if (ev->receivers[j] != NOT_USED)
{
msg_item->receivers[i++] = ev->receivers[j];
for (k = 0; k < MAX_LOCKS; k++)
if (locks[k].sid == ev->receivers[j])
{
/* create echo */
message_echo *echo = salloc(sizeof(message_echo));
echo->message = msg_item;
echo->message_id = event_id;
echo->next_echo = NULL;
if (locks[k].echo == NULL)
locks[k].echo = echo;
else
{
message_echo *p;
p = locks[k].echo;
while (p->next_echo != NULL)
p = p->next_echo;
p->next_echo = echo;
}
}
}
}
msg_item->next_message = NULL;
if (ev->messages == NULL)
{
msg_item->prev_message = NULL;
ev->messages = msg_item;
}
else
{
message_item *p;
p = ev->messages;
while (p->next_message != NULL)
p = p->next_message;
p->next_message = msg_item;
msg_item->prev_message = p;
}
}
}
}
