/**************************************************************************** * sched/timer/timer_settime.c * * Copyright (C) 2007-2010, 2013-2016, 2018 Gregory Nutt. All rights * reserved. * Author: Gregory Nutt * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in * the documentation and/or other materials provided with the * distribution. * 3. Neither the name NuttX nor the names of its contributors may be * used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. * ****************************************************************************/ /**************************************************************************** * Included Files ****************************************************************************/ #include #include #include #include #include #include #include "clock/clock.h" #include "timer/timer.h" #ifndef CONFIG_DISABLE_POSIX_TIMERS /**************************************************************************** * Private Function Prototypes ****************************************************************************/ static inline void timer_signotify(FAR struct posix_timer_s *timer); static inline void timer_restart(FAR struct posix_timer_s *timer, wdparm_t itimer); static void timer_timeout(int argc, wdparm_t itimer); /**************************************************************************** * Private Functions ****************************************************************************/ /**************************************************************************** * Name: timer_signotify * * Description: * This function basically re-implements nxsig_queue() so that the si_code * can be correctly set to SI_TIMER * * Input Parameters: * timer - A reference to the POSIX timer that just timed out * * Returned Value: * None * * Assumptions: * This function executes in the context of the watchod timer interrupt. * ****************************************************************************/ static inline void timer_signotify(FAR struct posix_timer_s *timer) { DEBUGVERIFY(nxsig_notification(timer->pt_owner, &timer->pt_event, SI_TIMER, &timer->pt_work)); } /**************************************************************************** * Name: timer_restart * * Description: * If a periodic timer has been selected, then restart the watchdog. * * Input Parameters: * timer - A reference to the POSIX timer that just timed out * * Returned Value: * None * * Assumptions: * This function executes in the context of the watchdog timer interrupt. * ****************************************************************************/ static inline void timer_restart(FAR struct posix_timer_s *timer, wdparm_t itimer) { /* If this is a repetitive timer, then restart the watchdog */ if (timer->pt_delay) { timer->pt_last = timer->pt_delay; (void)wd_start(timer->pt_wdog, timer->pt_delay, (wdentry_t)timer_timeout, 1, itimer); } } /**************************************************************************** * Name: timer_timeout * * Description: * This function is called if the timeout elapses before the condition is * signaled. * * Input Parameters: * argc - the number of arguments (should be 1) * itimer - A reference to the POSIX timer that just timed out * signo - The signal to use to wake up the task * * Returned Value: * None * * Assumptions: * This function executes in the context of the watchod timer interrupt. * ****************************************************************************/ static void timer_timeout(int argc, wdparm_t itimer) { #ifndef CONFIG_CAN_PASS_STRUCTS /* On many small machines, pointers are encoded and cannot be simply cast * from wdparm_t to struct tcb_s *. The following union works around this * (see wdogparm_t). */ union { FAR struct posix_timer_s *timer; wdparm_t itimer; } u; u.itimer = itimer; /* Send the specified signal to the specified task. Increment the * reference count on the timer first so that will not be deleted until * after the signal handler returns. */ u.timer->pt_crefs++; timer_signotify(u.timer); /* Release the reference. timer_release will return nonzero if the timer * was not deleted. */ if (timer_release(u.timer)) { /* If this is a repetitive timer, then restart the watchdog */ timer_restart(u.timer, itimer); } #else FAR struct posix_timer_s *timer = (FAR struct posix_timer_s *)itimer; /* Send the specified signal to the specified task. Increment the * reference count on the timer first so that will not be deleted until * after the signal handler returns. */ timer->pt_crefs++; timer_signotify(timer); /* Release the reference. timer_release will return nonzero if the timer * was not deleted. */ if (timer_release(timer)) { /* If this is a repetitive timer, the restart the watchdog */ timer_restart(timer, itimer); } #endif } /**************************************************************************** * Public Functions ****************************************************************************/ /**************************************************************************** * Name: timer_settime * * Description: * The timer_settime() function sets the time until the next expiration of * the timer specified by timerid from the it_value member of the value * argument and arm the timer if the it_value member of value is non-zero. * If the specified timer was already armed when timer_settime() is * called, this call will reset the time until next expiration to the * value specified. If the it_value member of value is zero, the timer * will be disarmed. The effect of disarming or resetting a timer with * pending expiration notifications is unspecified. * * If the flag TIMER_ABSTIME is not set in the argument flags, * timer_settime() will behave as if the time until next expiration is set * to be equal to the interval specified by the it_value member of value. * That is, the timer will expire in it_value nanoseconds from when the * call is made. If the flag TIMER_ABSTIME is set in the argument flags, * timer_settime() will behave as if the time until next expiration is set * to be equal to the difference between the absolute time specified by * the it_value member of value and the current value of the clock * associated with timerid. That is, the timer will expire when the clock * reaches the value specified by the it_value member of value. If the * specified time has already passed, the function will succeed and the * expiration notification will be made. * * The reload value of the timer will be set to the value specified by the * it_interval member of value. When a timer is armed with a non-zero * it_interval, a periodic (or repetitive) timer is specified. * * Time values that are between two consecutive non-negative integer * multiples of the resolution of the specified timer will be rounded up * to the larger multiple of the resolution. Quantization error will not * cause the timer to expire earlier than the rounded time value. * * If the argument ovalue is not NULL, the timer_settime() function will * store, in the location referenced by ovalue, a value representing the * previous amount of time before the timer would have expired, or zero if * the timer was disarmed, together with the previous timer reload value. * Timers will not expire before their scheduled time. * * Input Parameters: * timerid - The pre-thread timer, previously created by the call to * timer_create(), to be be set. * flags - Specifies characteristics of the timer (see above) * value - Specifies the timer value to set * ovalue - A location in which to return the time remaining from the * previous timer setting. (ignored) * * Returned Value: * If the timer_settime() succeeds, a value of 0 (OK) will be returned. * If an error occurs, the value -1 (ERROR) will be returned, and errno set * to indicate the error. * * EINVAL - The timerid argument does not correspond to an ID returned by * timer_create() but not yet deleted by timer_delete(). * EINVAL - A value structure specified a nanosecond value less than zero or * greater than or equal to 1000 million, and the it_value member of that * structure did not specify zero seconds and nanoseconds. * * Assumptions: * ****************************************************************************/ int timer_settime(timer_t timerid, int flags, FAR const struct itimerspec *value, FAR struct itimerspec *ovalue) { FAR struct posix_timer_s *timer = (FAR struct posix_timer_s *)timerid; irqstate_t intflags; sclock_t delay; int ret = OK; /* Some sanity checks */ if (!timer || !value) { set_errno(EINVAL); return ERROR; } /* Disarm the timer (in case the timer was already armed when timer_settime() * is called). */ (void)wd_cancel(timer->pt_wdog); /* Cancel any pending notification */ nxsig_cancel_notification(&timer->pt_work); /* If the it_value member of value is zero, the timer will not be re-armed */ if (value->it_value.tv_sec <= 0 && value->it_value.tv_nsec <= 0) { return OK; } /* Setup up any repetitive timer */ if (value->it_interval.tv_sec > 0 || value->it_interval.tv_nsec > 0) { (void)clock_time2ticks(&value->it_interval, &delay); /* REVISIT: Should pt_delay be sclock_t? */ timer->pt_delay = (int)delay; } else { timer->pt_delay = 0; } /* We need to disable timer interrupts through the following section so * that the system timer is stable. */ intflags = enter_critical_section(); /* Check if abstime is selected */ if ((flags & TIMER_ABSTIME) != 0) { /* Calculate a delay corresponding to the absolute time in 'value'. * NOTE: We have internal knowledge the clock_abstime2ticks only * returns an error if clockid != CLOCK_REALTIME. */ (void)clock_abstime2ticks(CLOCK_REALTIME, &value->it_value, &delay); } else { /* Calculate a delay assuming that 'value' holds the relative time * to wait. We have internal knowledge that clock_time2ticks always * returns success. */ (void)clock_time2ticks(&value->it_value, &delay); } /* If the time is in the past or now, then set up the next interval * instead (assuming a repetitive timer). */ if (delay <= 0) { delay = timer->pt_delay; } /* Then start the watchdog */ if (delay > 0) { /* REVISIT: Should pt_last be sclock_t? Should wd_start delay be * sclock_t? */ timer->pt_last = delay; ret = wd_start(timer->pt_wdog, delay, (wdentry_t)timer_timeout, 1, (uint32_t)((wdparm_t)timer)); if (ret < 0) { set_errno(-ret); ret = ERROR; } else { ret = OK; } } leave_critical_section(intflags); return ret; } #endif /* CONFIG_DISABLE_POSIX_TIMERS */