Timer Functions
[Core Library]

Collaboration diagram for Timer Functions:

Functions
switch_status_t	switch_core_timer_init (switch_timer_t *timer, const char *timer_name, int interval, int samples, switch_memory_pool_t *pool)
	Request a timer handle using given time module.
void	switch_time_calibrate_clock (void)
switch_status_t	switch_core_timer_next (switch_timer_t *timer)
	Wait for one cycle on an existing timer.
switch_status_t	switch_core_timer_step (switch_timer_t *timer)
	Step the timer one step.
switch_status_t	switch_core_timer_sync (switch_timer_t *timer)
switch_status_t	switch_core_timer_check (switch_timer_t *timer, switch_bool_t step)
	Check if the current step has been exceeded.
switch_status_t	switch_core_timer_destroy (switch_timer_t *timer)
	Destroy an allocated timer.

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Function Documentation

switch_status_t switch_core_timer_check	(	switch_timer_t *	timer,
		switch_bool_t	step
	)

Check if the current step has been exceeded.

Parameters:

	timer	the timer to wait on
	step	increment timer if a tick was detected

Returns:

the newest sample count

Definition at line 103 of file switch_core_timer.c.

References SWITCH_CHANNEL_LOG, SWITCH_LOG_ERROR, switch_log_printf(), and SWITCH_STATUS_GENERR.

{
        if (!timer->timer_interface || !timer->timer_interface->timer_check) {
                switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_ERROR, "Timer is not properly configured.\n");
                return SWITCH_STATUS_GENERR;
        }

        return timer->timer_interface->timer_check(timer, step);
}

switch_status_t switch_core_timer_destroy

(

switch_timer_t *

timer

)

Destroy an allocated timer.

Parameters:

timer

timer to destroy

Returns:

SWITCH_STATUS_SUCCESS after destruction

Definition at line 114 of file switch_core_timer.c.

References SWITCH_CHANNEL_LOG, switch_core_destroy_memory_pool, SWITCH_LOG_ERROR, switch_log_printf(), SWITCH_STATUS_GENERR, SWITCH_STATUS_SUCCESS, switch_test_flag, SWITCH_TIMER_FLAG_FREE_POOL, and UNPROTECT_INTERFACE.

Referenced by switch_ivr_clear_speech_cache(), switch_ivr_play_file(), switch_ivr_speak_text(), switch_rtp_change_interval(), switch_rtp_destroy(), and switch_rtp_udptl_mode().

{
        if (!timer->timer_interface || !timer->timer_interface->timer_destroy) {
                switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_ERROR, "Timer is not properly configured.\n");
                return SWITCH_STATUS_GENERR;
        }

        timer->timer_interface->timer_destroy(timer);
        UNPROTECT_INTERFACE(timer->timer_interface);

        if (switch_test_flag(timer, SWITCH_TIMER_FLAG_FREE_POOL)) {
                switch_core_destroy_memory_pool(&timer->memory_pool);
        }

        memset(timer, 0, sizeof(*timer));

        return SWITCH_STATUS_SUCCESS;
}

switch_status_t switch_core_timer_init	(	switch_timer_t *	timer,
		const char *	timer_name,
		int	interval,
		int	samples,
		switch_memory_pool_t *	pool
	)

Request a timer handle using given time module.

Parameters:

	timer	a timer object to allocate to
	timer_name	the name of the timer module to use
	interval	desired interval
	samples	the number of samples to increment on each cycle
	pool	the memory pool to use for allocation

Returns:

Definition at line 38 of file switch_core_timer.c.

References SWITCH_CHANNEL_LOG, switch_core_new_memory_pool, switch_loadable_module_get_timer_interface(), SWITCH_LOG_ERROR, switch_log_printf(), switch_set_flag, SWITCH_STATUS_GENERR, SWITCH_STATUS_SUCCESS, SWITCH_TIMER_FLAG_FREE_POOL, switch_timer_interface::timer_init, and UNPROTECT_INTERFACE.

Referenced by switch_ivr_play_file(), switch_ivr_speak_text(), switch_rtp_change_interval(), and switch_rtp_create().

{
        switch_timer_interface_t *timer_interface;
        switch_status_t status;
        memset(timer, 0, sizeof(*timer));
        if ((timer_interface = switch_loadable_module_get_timer_interface(timer_name)) == 0 || !timer_interface->timer_init) {
                switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_ERROR, "invalid timer %s!\n", timer_name);
                return SWITCH_STATUS_GENERR;
        }

        timer->interval = interval;
        timer->samples = samples;
        timer->samplecount = samples;
        timer->timer_interface = timer_interface;

        if (pool) {
                timer->memory_pool = pool;
        } else {
                if ((status = switch_core_new_memory_pool(&timer->memory_pool)) != SWITCH_STATUS_SUCCESS) {
                        UNPROTECT_INTERFACE(timer->timer_interface);
                        return status;
                }
                switch_set_flag(timer, SWITCH_TIMER_FLAG_FREE_POOL);
        }

        return timer->timer_interface->timer_init(timer);
}

switch_status_t switch_core_timer_next

(

switch_timer_t *

timer

)

Wait for one cycle on an existing timer.

Parameters:

timer

the timer to wait on

Returns:

the newest sample count

Definition at line 67 of file switch_core_timer.c.

References SWITCH_CHANNEL_LOG, SWITCH_LOG_ERROR, switch_log_printf(), SWITCH_STATUS_GENERR, and SWITCH_STATUS_SUCCESS.

Referenced by rtp_common_read(), switch_ivr_play_file(), and switch_ivr_speak_text_handle().

{
        if (!timer->timer_interface || !timer->timer_interface->timer_next) {
                switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_ERROR, "Timer is not properly configured.\n");
                return SWITCH_STATUS_GENERR;
        }

        if (timer->timer_interface->timer_next(timer) == SWITCH_STATUS_SUCCESS) {
                return SWITCH_STATUS_SUCCESS;
        } else {
                return SWITCH_STATUS_GENERR;
        }

}

switch_status_t switch_core_timer_step

(

switch_timer_t *

timer

)

Step the timer one step.

Parameters:

timer

the timer to wait on

Returns:

the newest sample count

Definition at line 82 of file switch_core_timer.c.

References SWITCH_CHANNEL_LOG, SWITCH_LOG_ERROR, switch_log_printf(), and SWITCH_STATUS_GENERR.

{
        if (!timer->timer_interface || !timer->timer_interface->timer_step) {
                switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_ERROR, "Timer is not properly configured.\n");
                return SWITCH_STATUS_GENERR;
        }

        return timer->timer_interface->timer_step(timer);
}

switch_status_t switch_core_timer_sync

(

switch_timer_t *

timer

)

Definition at line 93 of file switch_core_timer.c.

References SWITCH_CHANNEL_LOG, SWITCH_LOG_ERROR, switch_log_printf(), and SWITCH_STATUS_GENERR.

Referenced by read_rtp_packet(), rtp_common_read(), switch_ivr_play_file(), and switch_ivr_speak_text().

{
        if (!timer->timer_interface || !timer->timer_interface->timer_sync) {
                switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_ERROR, "Timer is not properly configured.\n");
                return SWITCH_STATUS_GENERR;
        }

        return timer->timer_interface->timer_sync(timer);
}

void switch_time_calibrate_clock

(

void

)

Definition at line 208 of file switch_time.c.

References average_time(), calc_step, do_sleep(), switch_runtime::microseconds_per_tick, OFFSET, runtime, SWITCH_CHANNEL_LOG, SWITCH_LOG_CONSOLE, switch_log_printf(), SWITCH_LOG_WARNING, switch_time_set_cond_yield(), and SWITCH_TRUE.

Referenced by switch_core_session_ctl(), and SWITCH_MODULE_LOAD_FUNCTION().

{
        int x;
        switch_interval_time_t avg, val = 1000, want = 1000;
        int over = 0, under = 0, good = 0, step = 50, diff = 0, retry = 0, lastgood = 0, one_k = 0;

#ifdef HAVE_CLOCK_GETRES
        struct timespec ts;
        long res = 0;
        clock_getres(CLOCK_MONOTONIC, &ts);
        res = ts.tv_nsec / 1000;


        if (res > 900 && res < 1100) {
                one_k = 1;
        }
        
        if (res > 1500) {
                switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_WARNING,
                                                  "Timer resolution of %ld microseconds detected!\n"
                                                  "Do you have your kernel timer frequency set to lower than 1,000Hz? "
                                                  "You may experience audio problems. Step MS %d\n", ts.tv_nsec / 1000, runtime.microseconds_per_tick / 1000);
                do_sleep(5000000);
                switch_time_set_cond_yield(SWITCH_TRUE);
                return;
        }
#endif

  top:
        val = 1000;
        step = 50;
        over = under = good = 0;
        OFFSET = 0;

        for (x = 0; x < 100; x++) {
                avg = average_time(val, 50);
                switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_CONSOLE, "Test: %ld Average: %ld Step: %d\n", (long) val, (long) avg, step);

                diff = abs((int) (want - avg));
                if (diff > 1500) {
                        switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_WARNING,
                                                          "Abnormally large timer gap %d detected!\n"
                                                          "Do you have your kernel timer frequency set to lower than 1,000Hz? You may experience audio problems.\n", diff);
                        do_sleep(5000000);
                        switch_time_set_cond_yield(SWITCH_TRUE);
                        return;
                }

                if (diff <= 100) {
                        lastgood = (int) val;
                }

                if (diff <= 2) {
                        under = over = 0;
                        lastgood = (int) val;
                        if (++good > 10) {
                                break;
                        }
                } else if (avg > want) {
                        if (under) {
                                calc_step();
                        }
                        under = good = 0;
                        if ((val - step) < 0) {
                                if (++retry > 2)
                                        break;
                                goto top;
                        }
                        val -= step;
                        over++;
                } else if (avg < want) {
                        if (over) {
                                calc_step();
                        }
                        over = good = 0;
                        if ((val - step) < 0) {
                                if (++retry > 2)
                                        break;
                                goto top;
                        }
                        val += step;
                        under++;
                }
        }

        if (good >= 10) {
                OFFSET = (int) (want - val);
                switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_CONSOLE, "Timer offset of %d calculated\n", OFFSET);
        } else if (lastgood) {
                OFFSET = (int) (want - lastgood);
                switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_CONSOLE, "Timer offset of %d calculated (fallback)\n", OFFSET);
                switch_time_set_cond_yield(SWITCH_TRUE);
        } else if (one_k) {
                OFFSET = 900;
                switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_CONSOLE, "Timer offset CANNOT BE DETECTED, forcing OFFSET to 900\n");
                switch_time_set_cond_yield(SWITCH_TRUE);
        } else {
                switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_CONSOLE, "Timer offset NOT calculated\n");
                switch_time_set_cond_yield(SWITCH_TRUE);
        }
}

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