static void
log_reader_update_watches(LogReader *self)
{
GIOCondition cond;
gboolean free_to_send;
gboolean line_is_ready_in_buffer;
main_loop_assert_main_thread();
if (!log_reader_is_opened(self))
return;
log_reader_start_watches_if_stopped(self);
free_to_send = log_source_free_to_send(&self->super);
if (!free_to_send)
{
log_reader_suspend_until_awoken(self);
return;
}
line_is_ready_in_buffer = log_proto_server_prepare(self->proto, &cond);
if (self->immediate_check || line_is_ready_in_buffer)
{
log_reader_force_check_in_next_poll(self);
return;
}
poll_events_update_watches(self->poll_events, cond);
}
static void
log_reader_update_watches(LogReader *self)
{
GIOCondition cond;
gint idle_timeout = -1;
main_loop_assert_main_thread();
log_reader_stop_idle_timer(self);
if (!log_reader_is_opened(self))
return;
log_reader_start_watches_if_stopped(self);
gboolean free_to_send = log_source_free_to_send(&self->super);
if (!free_to_send)
{
log_reader_suspend_until_awoken(self);
return;
}
LogProtoPrepareAction prepare_action = log_proto_server_prepare(self->proto, &cond, &idle_timeout);
if (idle_timeout > 0)
{
iv_validate_now();
self->idle_timer.expires = iv_now;
self->idle_timer.expires.tv_sec += idle_timeout;
iv_timer_register(&self->idle_timer);
}
if (self->immediate_check)
{
log_reader_force_check_in_next_poll(self);
return;
}
switch (prepare_action)
{
case LPPA_POLL_IO:
poll_events_update_watches(self->poll_events, cond);
break;
case LPPA_FORCE_SCHEDULE_FETCH:
log_reader_force_check_in_next_poll(self);
break;
case LPPA_SUSPEND:
log_reader_suspend_until_awoken(self);
break;
default:
g_assert_not_reached();
break;
}
}
static void
_update_watches(JournalReader *self)
{
gboolean free_to_send;
main_loop_assert_main_thread();
_start_watches_if_stopped(self);
free_to_send = log_source_free_to_send(&self->super);
if (!free_to_send)
{
_suspend_until_awoken(self);
return;
}
if (self->immediate_check)
{
_force_check_in_next_poll(self);
return;
}
poll_events_update_watches(self->poll_events, G_IO_IN);
}
/* follow timer callback. Check if the file has new content, or deleted or
* moved. Ran every follow_freq seconds. */
static void
poll_file_changes_check_file(gpointer s)
{
PollFileChanges *self = (PollFileChanges *) s;
struct stat st, followed_st;
off_t pos = -1;
gint fd = self->fd;
msg_trace("Checking if the followed file has new lines",
evt_tag_str("follow_filename", self->follow_filename));
if (fd >= 0)
{
pos = lseek(fd, 0, SEEK_CUR);
if (pos == (off_t) -1)
{
msg_error("Error invoking seek on followed file",
evt_tag_errno("error", errno));
goto reschedule;
}
if (fstat(fd, &st) < 0)
{
if (errno == ESTALE)
{
msg_trace("log_reader_fd_check file moved ESTALE",
evt_tag_str("follow_filename", self->follow_filename));
log_pipe_notify(self->control, NC_FILE_MOVED, self);
return;
}
else
{
msg_error("Error invoking fstat() on followed file",
evt_tag_errno("error", errno));
goto reschedule;
}
}
msg_trace("log_reader_fd_check",
evt_tag_int("pos", pos),
evt_tag_int("size", st.st_size));
if (pos < st.st_size || !S_ISREG(st.st_mode))
{
/* we have data to read */
poll_events_invoke_callback(s);
return;
}
else if (pos == st.st_size)
{
/* we are at EOF */
log_pipe_notify(self->control, NC_FILE_EOF, self);
}
else if (pos > st.st_size)
{
/* the last known position is larger than the current size of the file. it got truncated. Restart from the beginning. */
log_pipe_notify(self->control, NC_FILE_MOVED, self);
/* we may be freed by the time the notification above returns */
return;
}
}
if (self->follow_filename)
{
if (stat(self->follow_filename, &followed_st) != -1)
{
if (fd < 0 || (st.st_ino != followed_st.st_ino && followed_st.st_size > 0))
{
msg_trace("log_reader_fd_check file moved eof",
evt_tag_int("pos", pos),
evt_tag_int("size", followed_st.st_size),
evt_tag_str("follow_filename", self->follow_filename));
/* file was moved and we are at EOF, follow the new file */
log_pipe_notify(self->control, NC_FILE_MOVED, self);
/* we may be freed by the time the notification above returns */
return;
}
}
else
{
msg_verbose("Follow mode file still does not exist",
evt_tag_str("filename", self->follow_filename));
}
}
reschedule:
poll_events_update_watches(s, G_IO_IN);
}
