static int flush_send_file_service(const char *queue_id)
{
const char *myname = "flush_send_file_service";
VSTRING *queue_file;
struct utimbuf tbuf;
static char qmgr_scan_trigger[] = {
QMGR_REQ_SCAN_INCOMING, /* scan incoming queue */
};
/*
* Sanity check.
*/
if (!mail_queue_id_ok(queue_id))
return (FLUSH_STAT_BAD);
if (msg_verbose)
msg_info("%s: requesting delivery for queue_id %s", myname, queue_id);
queue_file = vstring_alloc(30);
tbuf.actime = tbuf.modtime = event_time();
if (flush_one_file(queue_id, queue_file, &tbuf, UNTHROTTLE_AFTER) > 0)
mail_trigger(MAIL_CLASS_PUBLIC, var_queue_service,
qmgr_scan_trigger, sizeof(qmgr_scan_trigger));
vstring_free(queue_file);
return (FLUSH_STAT_OK);
}
int mail_flush_maildrop(void)
{
static char wakeup[] = {TRIGGER_REQ_WAKEUP};
/*
* Trigger the pickup service.
*/
return (mail_trigger(MAIL_CLASS_PUBLIC, var_pickup_service,
wakeup, sizeof(wakeup)));
}
int mail_flush_deferred(void)
{
static char qmgr_trigger[] = {
QMGR_REQ_FLUSH_DEAD, /* all hosts, all transports */
QMGR_REQ_SCAN_ALL, /* all time stamps */
QMGR_REQ_SCAN_DEFERRED, /* scan deferred queue */
QMGR_REQ_SCAN_INCOMING, /* scan incoming queue */
};
/*
* Trigger the flush queue service.
*/
return (mail_trigger(MAIL_CLASS_PUBLIC, var_queue_service,
qmgr_trigger, sizeof(qmgr_trigger)));
}
static int flush_send_path(const char *path, int how)
{
const char *myname = "flush_send_path";
VSTRING *queue_id;
VSTRING *queue_file;
VSTREAM *log;
struct utimbuf tbuf;
static char qmgr_flush_trigger[] = {
QMGR_REQ_FLUSH_DEAD, /* flush dead site/transport cache */
};
static char qmgr_scan_trigger[] = {
QMGR_REQ_SCAN_INCOMING, /* scan incoming queue */
};
HTABLE *dup_filter;
int count;
/*
* Sanity check.
*/
if (!mail_queue_id_ok(path))
return (FLUSH_STAT_BAD);
/*
* Open the logfile. If the file does not exist, then there is no queued
* mail for this destination.
*/
if ((log = mail_queue_open(MAIL_QUEUE_FLUSH, path, O_RDWR, 0600)) == 0) {
if (errno != ENOENT)
msg_fatal("%s: open fast flush logfile %s: %m", myname, path);
return (FLUSH_STAT_OK);
}
/*
* We must lock the logfile, so that we don't lose information when it is
* truncated. Unfortunately, this means that the file can be locked for a
* significant amount of time. If things really get stuck the Postfix
* watchdog will take care of it.
*/
if (myflock(vstream_fileno(log), INTERNAL_LOCK, MYFLOCK_OP_EXCLUSIVE) < 0)
msg_fatal("%s: lock fast flush logfile %s: %m", myname, path);
/*
* With the UNTHROTTLE_BEFORE strategy, we ask the queue manager to
* unthrottle all transports and queues before we move a deferred queue
* file to the incoming queue. This minimizes a race condition where the
* queue manager seizes a queue file before it knows that we want to
* flush that message.
*
* This reduces the race condition time window to a very small amount (the
* flush server does not really know when the queue manager reads its
* command fifo). But there is a worse race, where the queue manager
* moves a deferred queue file to the active queue before we have a
* chance to expedite its delivery.
*/
if (how & UNTHROTTLE_BEFORE)
mail_trigger(MAIL_CLASS_PUBLIC, var_queue_service,
qmgr_flush_trigger, sizeof(qmgr_flush_trigger));
/*
* This is the part that dominates running time: schedule the listed
* queue files for delivery by updating their file time stamps and by
* moving them from the deferred queue to the incoming queue. This should
* take no more than a couple seconds under normal conditions. Filter out
* duplicate queue file names to avoid hammering the file system, with
* some finite limit on the amount of memory that we are willing to
* sacrifice for duplicate filtering. Graceful degradation.
*
* By moving selected queue files from the deferred queue to the incoming
* queue we optimize for the case where most deferred mail is for other
* sites. If that assumption does not hold, i.e. all deferred mail is for
* the same site, then doing a "fast flush" will cost more disk I/O than
* a "slow flush" that delivers the entire deferred queue. This penalty
* is only temporary - it will go away after we unite the active queue
* and the incoming queue.
*/
queue_id = vstring_alloc(10);
queue_file = vstring_alloc(10);
dup_filter = htable_create(10);
tbuf.actime = tbuf.modtime = event_time();
for (count = 0; vstring_get_nonl(queue_id, log) != VSTREAM_EOF; count++) {
if (!mail_queue_id_ok(STR(queue_id))) {
msg_warn("bad queue id \"%.30s...\" in fast flush logfile %s",
STR(queue_id), path);
continue;
}
if (dup_filter->used >= FLUSH_DUP_FILTER_SIZE
|| htable_find(dup_filter, STR(queue_id)) == 0) {
if (msg_verbose)
msg_info("%s: logfile %s: update queue file %s time stamps",
myname, path, STR(queue_id));
if (dup_filter->used <= FLUSH_DUP_FILTER_SIZE)
htable_enter(dup_filter, STR(queue_id), 0);
count += flush_one_file(STR(queue_id), queue_file, &tbuf, how);
} else {
if (msg_verbose)
msg_info("%s: logfile %s: skip queue file %s as duplicate",
myname, path, STR(queue_file));
}
}
htable_free(dup_filter, (void (*) (void *)) 0);
vstring_free(queue_file);
vstring_free(queue_id);
/*
* Truncate the fast flush log.
*/
if (count > 0 && ftruncate(vstream_fileno(log), (off_t) 0) < 0)
msg_fatal("%s: truncate fast flush logfile %s: %m", myname, path);
/*
* Workaround for noatime mounts. Use futimes() if available.
*/
(void) utimes(VSTREAM_PATH(log), (struct timeval *) 0);
/*
* Request delivery and clean up.
*/
if (myflock(vstream_fileno(log), INTERNAL_LOCK, MYFLOCK_OP_NONE) < 0)
msg_fatal("%s: unlock fast flush logfile %s: %m", myname, path);
if (vstream_fclose(log) != 0)
msg_warn("%s: read fast flush logfile %s: %m", myname, path);
if (count > 0) {
if (msg_verbose)
msg_info("%s: requesting delivery for logfile %s", myname, path);
mail_trigger(MAIL_CLASS_PUBLIC, var_queue_service,
qmgr_scan_trigger, sizeof(qmgr_scan_trigger));
}
return (FLUSH_STAT_OK);
}