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Diffstat (limited to 'nuttx/sched/sem_timedwait.c')
| -rw-r--r-- | nuttx/sched/sem_timedwait.c | 286 |
1 files changed, 0 insertions, 286 deletions
diff --git a/nuttx/sched/sem_timedwait.c b/nuttx/sched/sem_timedwait.c deleted file mode 100644 index 6a4724406..000000000 --- a/nuttx/sched/sem_timedwait.c +++ /dev/null @@ -1,286 +0,0 @@ -/**************************************************************************** - * sched/sem_timedwait.c - * - * Copyright (C) 2011 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 <unistd.h> -#include <semaphore.h> -#include <time.h> -#include <errno.h> -#include <wdog.h> -#include <debug.h> - -#include <nuttx/arch.h> - -#include "os_internal.h" -#include "clock_internal.h" -#include "sem_internal.h" - -/**************************************************************************** - * Pre-processor Definitions - ****************************************************************************/ - -/**************************************************************************** - * Private Type Declarations - ****************************************************************************/ - -/**************************************************************************** - * Global Variables - ****************************************************************************/ - -/**************************************************************************** - * Private Variables - ****************************************************************************/ - -/**************************************************************************** - * Private Functions - ****************************************************************************/ - -/**************************************************************************** - * Name: sem_timeout - * - * Description: - * This function is called if the timeout elapses before the message queue - * becomes non-empty. - * - * Parameters: - * argc - the number of arguments (should be 1) - * pid - the task ID of the task to wakeup - * - * Return Value: - * None - * - * Assumptions: - * - ****************************************************************************/ - -static void sem_timeout(int argc, uint32_t pid) -{ - FAR _TCB *wtcb; - irqstate_t flags; - - /* Disable interrupts to avoid race conditions */ - - flags = irqsave(); - - /* Get the TCB associated with this pid. It is possible that - * task may no longer be active when this watchdog goes off. - */ - - wtcb = sched_gettcb((pid_t)pid); - - /* It is also possible that an interrupt/context switch beat us to the - * punch and already changed the task's state. - */ - - if (wtcb && wtcb->task_state == TSTATE_WAIT_SEM) - { - /* Cancel the semaphore wait */ - - sem_waitirq(wtcb, ETIMEDOUT); - } - - /* Interrupts may now be enabled. */ - - irqrestore(flags); -} - -/**************************************************************************** - * Public Functions - ****************************************************************************/ - -/**************************************************************************** - * Name: sem_timedwait - * - * Description: - * This function will lock the semaphore referenced by sem as in the - * sem_wait() function. However, if the semaphore cannot be locked without - * waiting for another process or thread to unlock the semaphore by - * performing a sem_post() function, this wait will be terminated when the - * specified timeout expires. - * - * The timeout will expire when the absolute time specified by abstime - * passes, as measured by the clock on which timeouts are based (that is, - * when the value of that clock equals or exceeds abstime), or if the - * absolute time specified by abstime has already been passed at the - * time of the call. - * - * Parameters: - * sem - Semaphore object - * abstime - The absolute time to wait until a timeout is declared. - * - * Return Value: - * One success, the length of the selected message in bytes.is - * returned. On failure, -1 (ERROR) is returned and the errno - * is set appropriately: - * - * EINVAL The sem argument does not refer to a valid semaphore. Or the - * thread would have blocked, and the abstime parameter specified - * a nanoseconds field value less than zero or greater than or - * equal to 1000 million. - * ETIMEDOUT The semaphore could not be locked before the specified timeout - * expired. - * EDEADLK A deadlock condition was detected. - * EINTR A signal interrupted this function. - * - ****************************************************************************/ - -int sem_timedwait(FAR sem_t *sem, FAR const struct timespec *abstime) -{ - WDOG_ID wdog; - irqstate_t flags; - int ticks; - int err; - int ret = ERROR; - - DEBUGASSERT(up_interrupt_context() == false); - - /* Verify the input parameters and, in case of an error, set - * errno appropriately. - */ - -#ifdef CONFIG_DEBUG - if (!abstime || !sem) - { - err = EINVAL; - goto errout; - } -#endif - - /* Create a watchdog. We will not actually need this watchdog - * unless the the semaphore is unavailable, but we will reserve it up - * front before we enter the following critical section. - */ - - wdog = wd_create(); - if (!wdog) - { - err = ENOMEM; - goto errout; - } - - /* We will disable interrupts until we have completed the semaphore - * wait. We need to do this (as opposed to just disabling pre-emption) - * because there could be interrupt handlers that are asynchronoulsy - * posting semaphores and to prevent race conditions with watchdog - * timeout. This is not too bad because interrupts will be re- - * enabled while we are blocked waiting for the semaphore. - */ - - flags = irqsave(); - - /* Try to take the semaphore without waiting. */ - - ret = sem_trywait(sem); - if (ret == 0) - { - /* We got it! */ - - irqrestore(flags); - wd_delete(wdog); - return OK; - } - - /* We will have to wait for the semphore. Make sure that we were provided - * with a valid timeout. - */ - - if (abstime->tv_sec < 0 || abstime->tv_nsec > 1000000000) - { - err = EINVAL; - goto errout_disabled; - } - - /* Convert the timespec to clock ticks. We must have interrupts - * disabled here so that this time stays valid until the wait begins. - */ - - err = clock_abstime2ticks(CLOCK_REALTIME, abstime, &ticks); - - /* If the time has already expired return immediately. */ - - if (err == OK && ticks <= 0) - { - err = ETIMEDOUT; - goto errout_disabled; - } - - /* Handle any time-related errors */ - - if (err != OK) - { - goto errout_disabled; - } - - /* Start the watchdog */ - - err = OK; - wd_start(wdog, ticks, (wdentry_t)sem_timeout, 1, getpid()); - - /* Now perform the blocking wait */ - - ret = sem_wait(sem); - - /* Stop the watchdog timer */ - - wd_cancel(wdog); - - /* We can now restore interrupts and delete the watchdog */ - - irqrestore(flags); - wd_delete(wdog); - - /* We are either returning success or an error detected by sem_wait() - * or the timeout detected by sem_timeout(). The 'errno' value has - * been set appropriately by sem_wait() or sem_timeout() in those - * cases. - */ - - return ret; - -/* Error exits */ - -errout_disabled: - irqrestore(flags); - wd_delete(wdog); -errout: - set_errno(err); - return ERROR; -} |