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Diffstat (limited to 'nuttx/sched/timer_settime.c')
| -rw-r--r-- | nuttx/sched/timer_settime.c | 397 |
1 files changed, 397 insertions, 0 deletions
diff --git a/nuttx/sched/timer_settime.c b/nuttx/sched/timer_settime.c new file mode 100644 index 000000000..1814ba898 --- /dev/null +++ b/nuttx/sched/timer_settime.c @@ -0,0 +1,397 @@ +/******************************************************************************** + * sched/timer_settime.c + * + * Copyright (C) 2007-2010 Gregory Nutt. All rights reserved. + * Author: Gregory Nutt <gnutt@nuttx.org> + * + * 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 <nuttx/config.h> + +#include <stdint.h> +#include <time.h> +#include <string.h> +#include <errno.h> + +#include "os_internal.h" +#include "clock_internal.h" +#include "sig_internal.h" +#include "timer_internal.h" + +#ifndef CONFIG_DISABLE_POSIX_TIMERS + +/******************************************************************************** + * Definitions + ********************************************************************************/ + +/******************************************************************************** + * Private Data + ********************************************************************************/ + +/******************************************************************************** + * Public Data + ********************************************************************************/ + +/******************************************************************************** + * Private Function Prototypes + ********************************************************************************/ + +static void inline timer_sigqueue(FAR struct posix_timer_s *timer); +static void inline timer_restart(FAR struct posix_timer_s *timer, uint32_t itimer); +static void timer_timeout(int argc, uint32_t itimer); + +/******************************************************************************** + * Private Functions + ********************************************************************************/ + +/******************************************************************************** + * Name: timer_sigqueue + * + * Description: + * This function basically reimplements sigqueue() so that the si_code can + * be correctly set to SI_TIMER + * + * Parameters: + * timer - A reference to the POSIX timer that just timed out + * + * Return Value: + * None + * + * Assumptions: + * This function executes in the context of the watchod timer interrupt. + * + ********************************************************************************/ + +static void inline timer_sigqueue(FAR struct posix_timer_s *timer) +{ + FAR _TCB *tcb; + + /* Get the TCB of the receiving task */ + + tcb = sched_gettcb(timer->pt_owner); + if (tcb) + { + siginfo_t info; + + /* Create the siginfo structure */ + + info.si_signo = timer->pt_signo; + info.si_code = SI_TIMER; +#ifdef CONFIG_CAN_PASS_STRUCTS + info.si_value = timer->pt_value; +#else + info.si_value.sival_ptr = timer->pt_value.sival_ptr; +#endif + + /* Send the signal */ + + (void)sig_received(tcb, &info); + } +} + +/******************************************************************************** + * Name: timer_restart + * + * Description: + * If a periodic timer has been selected, then restart the watchdog. + * + * Parameters: + * timer - A reference to the POSIX timer that just timed out + * + * Return Value: + * None + * + * Assumptions: + * This function executes in the context of the watchod timer interrupt. + * + ********************************************************************************/ + +static void inline timer_restart(FAR struct posix_timer_s *timer, uint32_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. + * + * 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 + * + * Return Value: + * None + * + * Assumptions: + * This function executes in the context of the watchod timer interrupt. + * + ********************************************************************************/ + +static void timer_timeout(int argc, uint32_t itimer) +{ +#ifndef CONFIG_CAN_PASS_STRUCTS + /* On many small machines, pointers are encoded and cannot be simply cast from + * uint32_t to _TCB*. The following union works around this (see wdogparm_t). + */ + + union + { + FAR struct posix_timer_s *timer; + uint32_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_sigqueue(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, the restart the watchdog */ + + timer_restart(u.timer, itimer); + } +#else + /* (casting to uintptr_t first eliminates complaints on some architectures + * where the sizeof uint32_t is different from the size of a pointer). + */ + + FAR struct posix_timer_s *timer = (FAR struct posix_timer_s *)((uintptr_t)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_sigqueue(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. + * + * Parameters: + * timerid - The pre-thread timer, previously created by the call to + * timer_create(), to be be set. + * flags - Specifie 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) + * + * Return 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 state; + int delay; + int ret = OK; + + /* Some sanity checks */ + + if (!timer || !value) + { + 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); + + /* 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 repititive timer */ + + if (value->it_interval.tv_sec > 0 || value->it_interval.tv_nsec > 0) + { + (void)clock_time2ticks(&value->it_interval, &timer->pt_delay); + } + else + { + timer->pt_delay = 0; + } + + /* We need to disable timer interrupts through the following section so + * that the system timer is stable. + */ + + state = irqsave(); + + /* Check if abstime is selected */ + + if ((flags & TIMER_ABSTIME) != 0) + { +#ifdef CONFIG_DISABLE_CLOCK + /* Absolute timing depends upon having access to clock functionality */ + + errno = ENOSYS; + return ERROR; +#else + /* 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); +#endif + } + 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 repititive timer). + */ + + if (delay <= 0) + { + delay = timer->pt_delay; + } + + /* Then start the watchdog */ + + + if (delay > 0) + { + timer->pt_last = delay; + ret = wd_start(timer->pt_wdog, delay, (wdentry_t)timer_timeout, + 1, (uint32_t)((uintptr_t)timer)); + } + + irqrestore(state); + return ret; +} + +#endif /* CONFIG_DISABLE_POSIX_TIMERS */ |