![](/media/cache/img/default_profile.jpg.50x50_q85.jpg)
Control of mbed using OSC. Based on code from the Make Controller. Right now you can turn the onboard LEDs on/off and toggle 8 digital out pins. More I/O will be done in the future.
lwip/lwIP/core/sys.c
- Committer:
- pehrhovey
- Date:
- 2010-03-17
- Revision:
- 0:439354122597
File content as of revision 0:439354122597:
/** * @file * lwIP Operating System abstraction * */ /* * 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/opt.h" #if (NO_SYS == 0) /* don't build if not configured for use in lwipopts.h */ #include "lwip/sys.h" #include "lwip/def.h" #include "lwip/memp.h" #include "lwip/tcpip.h" /** * Struct used for sys_sem_wait_timeout() to tell wether the time * has run out or the semaphore has really become available. */ struct sswt_cb { s16_t timeflag; sys_sem_t *psem; }; /** * Wait (forever) for a message to arrive in an mbox. * While waiting, timeouts (for this thread) are processed. * * @param mbox the mbox to fetch the message from * @param msg the place to store the message */ void sys_mbox_fetch(sys_mbox_t mbox, void **msg) { u32_t time_needed; struct sys_timeouts *timeouts; struct sys_timeo *tmptimeout; sys_timeout_handler h; void *arg; again: timeouts = sys_arch_timeouts(); if (!timeouts || !timeouts->next) { UNLOCK_TCPIP_CORE(); time_needed = sys_arch_mbox_fetch(mbox, msg, 0); LOCK_TCPIP_CORE(); } else { if (timeouts->next->time > 0) { UNLOCK_TCPIP_CORE(); time_needed = sys_arch_mbox_fetch(mbox, msg, timeouts->next->time); LOCK_TCPIP_CORE(); } else { time_needed = SYS_ARCH_TIMEOUT; } if (time_needed == 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, 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_needed < timeouts->next->time) { timeouts->next->time -= time_needed; } else { timeouts->next->time = 0; } } } } /** * Wait (forever) for a semaphore to become available. * While waiting, timeouts (for this thread) are processed. * * @param sem semaphore to wait for */ void sys_sem_wait(sys_sem_t sem) { u32_t time_needed; struct sys_timeouts *timeouts; struct sys_timeo *tmptimeout; sys_timeout_handler h; void *arg; again: timeouts = sys_arch_timeouts(); if (!timeouts || !timeouts->next) { sys_arch_sem_wait(sem, 0); } else { if (timeouts->next->time > 0) { time_needed = sys_arch_sem_wait(sem, timeouts->next->time); } else { time_needed = SYS_ARCH_TIMEOUT; } if (time_needed == 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_needed < timeouts->next->time) { timeouts->next->time -= time_needed; } else { timeouts->next->time = 0; } } } } /** * Create a one-shot timer (aka timeout). Timeouts are processed in the * following cases: * - while waiting for a message using sys_mbox_fetch() * - while waiting for a semaphore using sys_sem_wait() or sys_sem_wait_timeout() * - while sleeping using the inbuilt sys_msleep() * * @param msecs time in milliseconds after that the timer should expire * @param h callback function to call when msecs have elapsed * @param arg argument to pass to the callback function */ void sys_timeout(u32_t msecs, sys_timeout_handler h, void *arg) { struct sys_timeouts *timeouts; struct sys_timeo *timeout, *t; timeout = memp_malloc(MEMP_SYS_TIMEOUT); if (timeout == NULL) { LWIP_ASSERT("sys_timeout: timeout != NULL", 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)); if (timeouts == NULL) { LWIP_ASSERT("sys_timeout: timeouts != NULL", timeouts != NULL); return; } 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. * * @note This function only works as expected if there is only one timeout * calling 'h' in the list of timeouts. * * @param h callback function that would be called by the timeout * @param arg callback argument that would be passed to h */ void sys_untimeout(sys_timeout_handler h, void *arg) { struct sys_timeouts *timeouts; struct sys_timeo *prev_t, *t; timeouts = sys_arch_timeouts(); if (timeouts == NULL) { LWIP_ASSERT("sys_untimeout: timeouts != NULL", timeouts != NULL); return; } 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; } /** * Timeout handler function for sys_sem_wait_timeout() * * @param arg struct sswt_cb* used to signal a semaphore and end waiting. */ static void sswt_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) * * @param sem semaphore to wait * @param timeout timeout in ms (0: wait forever) * @return 0 on timeout, 1 otherwise */ int sys_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; } } /** * Sleep for some ms. Timeouts are processed while sleeping. * * @param ms number of milliseconds to sleep */ void sys_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 */