/* * Copyright (c) 2001-2004 Swedish Institute of Computer Science. * All rights reserved. * * 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. The name of the author may not be used to endorse or promote products *    derived from this software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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. * * This file is part of the lwIP TCP/IP stack. * * Author: Adam Dunkels <adam@sics.se> * */#include "lwip/sys.h"#include "lwip/opt.h"#include "lwip/def.h"#include "lwip/memp.h"#if (NO_SYS == 0)struct sswt_cb{    s16_t timeflag;    sys_sem_t *psem;};voidsys_mbox_fetch(sys_mbox_t mbox, void **msg){  u32_t time;  struct sys_timeouts *timeouts;  struct sys_timeout *tmptimeout;  sys_timeout_handler h;  void *arg; again:  timeouts = sys_arch_timeouts();  if (!timeouts || !timeouts->next) {    sys_arch_mbox_fetch(mbox, msg, 0);  } else {    if (timeouts->next->time > 0) {      time = sys_arch_mbox_fetch(mbox, msg, timeouts->next->time);    } else {      time = SYS_ARCH_TIMEOUT;    }    if (time == SYS_ARCH_TIMEOUT) {      /* If time == SYS_ARCH_TIMEOUT, a timeout occured before a message   could be fetched. We should now call the timeout handler and   deallocate the memory allocated for the timeout. */      tmptimeout = timeouts->next;      timeouts->next = tmptimeout->next;      h = tmptimeout->h;      arg = tmptimeout->arg;      memp_free(MEMP_SYS_TIMEOUT, tmptimeout);      if (h != NULL) {        LWIP_DEBUGF(SYS_DEBUG, ("smf calling h=%p(%p)\n", (void *)h, (void *)arg));      	h(arg);      }      /* We try again to fetch a message from the mbox. */      goto again;    } else {      /* If time != SYS_ARCH_TIMEOUT, a message was received before the timeout   occured. The time variable is set to the number of   milliseconds we waited for the message. */      if (time <= timeouts->next->time) {  timeouts->next->time -= time;      } else {  timeouts->next->time = 0;      }    }  }}voidsys_sem_wait(sys_sem_t sem){  u32_t time;  struct sys_timeouts *timeouts;  struct sys_timeout *tmptimeout;  sys_timeout_handler h;  void *arg;  /*  while (sys_arch_sem_wait(sem, 1000) == 0);      return;*/ again:  timeouts = sys_arch_timeouts();  if (!timeouts || !timeouts->next) {    sys_arch_sem_wait(sem, 0);  } else {    if (timeouts->next->time > 0) {      time = sys_arch_sem_wait(sem, timeouts->next->time);    } else {      time = SYS_ARCH_TIMEOUT;    }    if (time == SYS_ARCH_TIMEOUT) {      /* If time == SYS_ARCH_TIMEOUT, a timeout occured before a message   could be fetched. We should now call the timeout handler and   deallocate the memory allocated for the timeout. */      tmptimeout = timeouts->next;      timeouts->next = tmptimeout->next;      h = tmptimeout->h;      arg = tmptimeout->arg;      memp_free(MEMP_SYS_TIMEOUT, tmptimeout);      if (h != NULL) {        LWIP_DEBUGF(SYS_DEBUG, ("ssw h=%p(%p)\n", (void *)h, (void *)arg));        h(arg);      }      /* We try again to fetch a message from the mbox. */      goto again;    } else {      /* If time != SYS_ARCH_TIMEOUT, a message was received before the timeout   occured. The time variable is set to the number of   milliseconds we waited for the message. */      if (time <= timeouts->next->time) {  timeouts->next->time -= time;      } else {  timeouts->next->time = 0;      }    }  }}voidsys_timeout(u32_t msecs, sys_timeout_handler h, void *arg){  struct sys_timeouts *timeouts;  struct sys_timeout *timeout, *t;  timeout = memp_malloc(MEMP_SYS_TIMEOUT);  if (timeout == NULL) {    return;  }  timeout->next = NULL;  timeout->h = h;  timeout->arg = arg;  timeout->time = msecs;  timeouts = sys_arch_timeouts();  LWIP_DEBUGF(SYS_DEBUG, ("sys_timeout: %p msecs=%"U32_F" h=%p arg=%p\n",    (void *)timeout, msecs, (void *)h, (void *)arg));  LWIP_ASSERT("sys_timeout: timeouts != NULL", timeouts != NULL);  if (timeouts->next == NULL) {    timeouts->next = timeout;    return;  }  if (timeouts->next->time > msecs) {    timeouts->next->time -= msecs;    timeout->next = timeouts->next;    timeouts->next = timeout;  } else {    for(t = timeouts->next; t != NULL; t = t->next) {      timeout->time -= t->time;      if (t->next == NULL || t->next->time > timeout->time) {        if (t->next != NULL) {          t->next->time -= timeout->time;        }        timeout->next = t->next;        t->next = timeout;        break;      }    }  }}/* Go through timeout list (for this task only) and remove the first matching entry,   even though the timeout has not triggered yet.*/voidsys_untimeout(sys_timeout_handler h, void *arg){    struct sys_timeouts *timeouts;    struct sys_timeout *prev_t, *t;    timeouts = sys_arch_timeouts();    if (timeouts->next == NULL)        return;    for (t = timeouts->next, prev_t = NULL; t != NULL; prev_t = t, t = t->next)    {        if ((t->h == h) && (t->arg == arg))        {            /* We have a match */            /* Unlink from previous in list */            if (prev_t == NULL)                timeouts->next = t->next;            else                prev_t->next = t->next;            /* If not the last one, add time of this one back to next */            if (t->next != NULL)                t->next->time += t->time;            memp_free(MEMP_SYS_TIMEOUT, t);            return;        }    }    return;}static voidsswt_handler(void *arg){    struct sswt_cb *sswt_cb = (struct sswt_cb *) arg;    /* Timeout. Set flag to TRUE and signal semaphore */    sswt_cb->timeflag = 1;    sys_sem_signal(*(sswt_cb->psem));}/* Wait for a semaphore with timeout (specified in ms) *//* timeout = 0: wait forever *//* Returns 0 on timeout. 1 otherwise */intsys_sem_wait_timeout(sys_sem_t sem, u32_t timeout){    struct sswt_cb sswt_cb;    sswt_cb.psem = &sem;    sswt_cb.timeflag = 0;    /* If timeout is zero, then just wait forever */    if (timeout > 0)        /* Create a timer and pass it the address of our flag */        sys_timeout(timeout, sswt_handler, &sswt_cb);    sys_sem_wait(sem);    /* Was it a timeout? */    if (sswt_cb.timeflag)    {        /* timeout */        return 0;    } else {        /* Not a timeout. Remove timeout entry */        sys_untimeout(sswt_handler, &sswt_cb);        return 1;    }}voidsys_msleep(u32_t ms){  sys_sem_t delaysem = sys_sem_new(0);  sys_sem_wait_timeout(delaysem, ms);  sys_sem_free(delaysem);}#endif /* NO_SYS */