/*
    ChibiOS/RT - Copyright (C) 2006,2007,2008,2009,2010,
                 2011,2012 Giovanni Di Sirio.

    This file is part of ChibiOS/RT.

    ChibiOS/RT is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 3 of the License, or
    (at your option) any later version.

    ChibiOS/RT is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/
/*
 * **** This file incorporates work covered by the following copyright and ****
 * **** permission notice:                                                 ****
 *
 * 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>
 *
 */

// see http://lwip.wikia.com/wiki/Porting_for_an_OS for instructions

#include "ch.h"

#include "lwip/opt.h"
#include "lwip/mem.h"
#include "lwip/sys.h"
#include "lwip/stats.h"

#include "arch/cc.h"
#include "arch/sys_arch.h"

void sys_init(void) {

}

err_t sys_sem_new(sys_sem_t *sem, u8_t count) {

  *sem = chHeapAlloc(NULL, sizeof(Semaphore));
  if (*sem == 0) {
    SYS_STATS_INC(sem.err);
    return ERR_MEM;
  }
  else {
    chSemInit(*sem, (cnt_t)count);
    SYS_STATS_INC_USED(sem);
    return ERR_OK;
  }
}

void sys_sem_free(sys_sem_t *sem) {

  chHeapFree(*sem);
  *sem = SYS_SEM_NULL;
  SYS_STATS_DEC(sem.used);
}

void sys_sem_signal(sys_sem_t *sem) {

  chSemSignal(*sem);
}

u32_t sys_arch_sem_wait(sys_sem_t *sem, u32_t timeout) {
  systime_t time, tmo;

  chSysLock();
  tmo = timeout > 0 ? (systime_t)timeout : TIME_INFINITE;
  time = chTimeNow();
  if (chSemWaitTimeoutS(*sem, tmo) != RDY_OK)
    time = SYS_ARCH_TIMEOUT;
  else
    time = chTimeNow() - time;
  chSysUnlock();
  return time;
}

int sys_sem_valid(sys_sem_t *sem) {
  return *sem != SYS_SEM_NULL;
}

// typically called within lwIP after freeing a semaphore
// to make sure the pointer is not left pointing to invalid data
void sys_sem_set_invalid(sys_sem_t *sem) {
  *sem = SYS_SEM_NULL;
}

err_t sys_mbox_new(sys_mbox_t *mbox, int size) {
  
  *mbox = chHeapAlloc(NULL, sizeof(Mailbox) + sizeof(msg_t) * size);
  if (*mbox == 0) {
    SYS_STATS_INC(mbox.err);
    return ERR_MEM;
  }
  else {
    chMBInit(*mbox, (void *)(((uint8_t *)*mbox) + sizeof(Mailbox)), size);
    SYS_STATS_INC(mbox.used);
    return ERR_OK;
  }
}

void sys_mbox_free(sys_mbox_t *mbox) {

  if (chMBGetUsedCountI(*mbox) != 0) {
    // If there are messages still present in the mailbox when the mailbox
    // is deallocated, it is an indication of a programming error in lwIP
    // and the developer should be notified.
    SYS_STATS_INC(mbox.err);
    chMBReset(*mbox);
  }
  chHeapFree(*mbox);
  *mbox = SYS_MBOX_NULL;
  SYS_STATS_DEC(mbox.used);
}

void sys_mbox_post(sys_mbox_t *mbox, void *msg) {

  chMBPost(*mbox, (msg_t)msg, TIME_INFINITE);
}

err_t sys_mbox_trypost(sys_mbox_t *mbox, void *msg) {

  if (chMBPost(*mbox, (msg_t)msg, TIME_IMMEDIATE) == RDY_TIMEOUT) {
    SYS_STATS_INC(mbox.err);
    return ERR_MEM;
  }
  return ERR_OK;
}

u32_t sys_arch_mbox_fetch(sys_mbox_t *mbox, void **msg, u32_t timeout) {
  systime_t time, tmo;

  chSysLock();
  tmo = timeout > 0 ? (systime_t)timeout : TIME_INFINITE;
  time = chTimeNow();
  if (chMBFetchS(*mbox, (msg_t *)msg, tmo) != RDY_OK)
    time = SYS_ARCH_TIMEOUT;
  else
    time = chTimeNow() - time;
  chSysUnlock();
  return time;
}

u32_t sys_arch_mbox_tryfetch(sys_mbox_t *mbox, void **msg) {

  if (chMBFetch(*mbox, (msg_t *)msg, TIME_IMMEDIATE) == RDY_TIMEOUT)
    return SYS_MBOX_EMPTY;
  return 0;
}

int sys_mbox_valid(sys_mbox_t *mbox) {
  return *mbox != SYS_MBOX_NULL;
}

// typically called within lwIP after freeing an mbox
// to make sure the pointer is not left pointing to invalid data
void sys_mbox_set_invalid(sys_mbox_t *mbox) {
  *mbox = SYS_MBOX_NULL;
}

sys_thread_t sys_thread_new(const char *name, lwip_thread_fn thread,
                            void *arg, int stacksize, int prio) {

  size_t wsz;
  void *wsp;

  (void)name;
  wsz = THD_WA_SIZE(stacksize);
  wsp = chCoreAlloc(wsz);
  if (wsp == NULL)
    return NULL;
  return (sys_thread_t)chThdCreateStatic(wsp, wsz, prio, (tfunc_t)thread, arg);
}

sys_prot_t sys_arch_protect(void) {

  chSysLock();
  return 0;
}

void sys_arch_unprotect(sys_prot_t pval) {

  (void)pval;
  chSysUnlock();
}