diff options
Diffstat (limited to 'drivers/dahdi/dahdi-base.c')
| -rw-r--r-- | drivers/dahdi/dahdi-base.c | 32 |
1 files changed, 29 insertions, 3 deletions
diff --git a/drivers/dahdi/dahdi-base.c b/drivers/dahdi/dahdi-base.c index a9cd775..2a5d6f9 100644 --- a/drivers/dahdi/dahdi-base.c +++ b/drivers/dahdi/dahdi-base.c @@ -8617,14 +8617,40 @@ static void process_timers(void) spin_unlock(&dahdi_timer_lock); } -static unsigned int dahdi_timer_poll(struct file *file, struct poll_table_struct *wait_table) +/** + * dahdi_timer_poll - Poll function for a dahdi_timer. + * @file: Open timer handle. + * @wait_table: Just passing through... + * + * Returns 0 if there isn't anything to wake us up, otherwise POLLPRI if there + * is an event waiting on the timer. + * + * Older versions of Asterisk depend on the behavior that this poll will block + * indefintely if the timer has not been configured, so if there is no rate + * attached to the timer, this function must return 0. + * + */ +static unsigned int +dahdi_timer_poll(struct file *file, struct poll_table_struct *wait_table) { struct dahdi_timer *timer = file->private_data; - struct dahdi_timer_rate *rate = timer->rate; + struct dahdi_timer_rate *rate; - if (!rate || !timer) + if (!timer) return -EINVAL; + rate = timer->rate; + + if (!rate) { + static bool __once; + if (!__once) { + __once = true; + module_printk(KERN_NOTICE, + "Calling poll on unconfigured timer.\n"); + } + return 0; + } + poll_wait(file, &rate->sel, wait_table); if (atomic_read(&timer->tripped) || atomic_read(&timer->ping)) return POLLPRI; |