text: /*
   * Copyright (c) 2009, 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. Neither the name of the Institute 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 INSTITUTE 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 INSTITUTE 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.
   *
   * This file is part of the Contiki operating system.
   *
   * $Id: shell-rime-sendcmd.c,v 1.2 2009/11/08 19:43:00 adamdunkels Exp $
   */
  
  #include "contiki.h"
  #include "contiki-conf.h"
  #include "shell-rime.h"
  
  #include "dev/leds.h"
  
  #include "lib/crc16.h"
  #include "lib/random.h"
  
  #include "net/rime.h"
  #include "net/rime/unicast.h"
  
  #include "net/rime/timesynch.h"
  
  #if CONTIKI_TARGET_NETSIM
  #include "ether.h"
  #endif /* CONTIKI_TARGET_NETSIM */
  
  #include <stdio.h>
  #ifndef HAVE_SNPRINTF
  int snprintf(char *str, size_t size, const char *format, ...);
  #endif /* HAVE_SNPRINTF */
  #include <string.h>
  
  #define CMDMSG_HDR_SIZE 2
  
  struct cmd_msg {
    uint16_t crc;
    char sendcmd[1];
  };
  
  static struct unicast_conn uc;
  /*---------------------------------------------------------------------------*/
  PROCESS(shell_sendcmd_process, "sendcmd");
  PROCESS(shell_sendcmd_server_process, "sendcmd server");
  SHELL_COMMAND(sendcmd_command,
            "sendcmd",
            "sendcmd <node addr> <command>: send a command to the specified one-hop node",
            &shell_sendcmd_process);
  /*---------------------------------------------------------------------------*/
  PROCESS_THREAD(shell_sendcmd_server_process, ev, data)
  {
    static struct process *child_command;
    int err;
    PROCESS_BEGIN();
  
    /* XXX: direct output to null. */
    /*  printf("sendcmd server got command string '%s'\n", (char *)data);*/
    err = shell_start_command(data, strlen((char * )data), NULL, &child_command);
    if(err == SHELL_FOREGROUND && process_is_running(child_command)) {
      PROCESS_WAIT_EVENT_UNTIL(ev == PROCESS_EVENT_EXIT ||
                   (ev == PROCESS_EVENT_EXITED &&
                    data == child_command));
      if(ev == PROCESS_EVENT_EXIT) {
        process_exit(child_command);
      }
    }
  
    PROCESS_END();
  }
  /*---------------------------------------------------------------------------*/
  PROCESS_THREAD(shell_sendcmd_process, ev, data)
  {
    struct cmd_msg  *msg;
    int len;
    rimeaddr_t addr;
    const char *nextptr;
    char buf[32];
  
    PROCESS_BEGIN();
  
    addr.u8[0] = shell_strtolong(data, &nextptr);
    if(nextptr == data || *nextptr != '.') {
      shell_output_str(&sendcmd_command,
               "sendcmd <node addr>: receiver must be specified", "");
      PROCESS_EXIT();
    }
    ++nextptr;
    addr.u8[1] = shell_strtolong(nextptr, &nextptr);
  
    snprintf(buf, sizeof(buf), "%d.%d", addr.u8[0], addr.u8[1]);
    shell_output_str(&sendcmd_command, "Sending command to ", buf);
  
    /* Get the length of the command line, excluding a terminating NUL character. */
    len = strlen((char *)nextptr);
  
    /* Check the length of the command line to see that it is small
       enough to fit in a packet. We count with 32 bytes of header,
       which may be a little too much, but at least we are on the safe
       side. */
    if(len > PACKETBUF_SIZE - 32) {
      snprintf(buf, sizeof(buf), "%d", len);
      shell_output_str(&sendcmd_command, "command line too large: ", buf);
      PROCESS_EXIT();
    }
  
    packetbuf_clear();
    msg = packetbuf_dataptr();
    packetbuf_set_datalen(len + 1 + CMDMSG_HDR_SIZE);
    strcpy(msg->sendcmd, nextptr);
  
    /* Terminate the string with a NUL character. */
    msg->sendcmd[len] = 0;
    msg->crc = crc16_data(msg->sendcmd, len, 0);
    /*    printf("sendcmd sending '%s'\n", msg->sendcmd);*/
    unicast_send(&uc, &addr);
  
    PROCESS_END();
  }
  /*---------------------------------------------------------------------------*/
  static void
  recv_uc(struct unicast_conn *c, const rimeaddr_t *from)
  {
    struct cmd_msg *msg;
    uint16_t crc;
    int len;
  
    msg = packetbuf_dataptr();
  
    if(packetbuf_datalen() > 1 + CMDMSG_HDR_SIZE) {
  
      /* First ensure that the old process is killed. */
      process_exit(&shell_sendcmd_server_process);
  
      len = packetbuf_datalen() - 1 - CMDMSG_HDR_SIZE;
  
      /* Make sure that the incoming command is null-terminated. */
      msg->sendcmd[len] = 0;
      memcpy(&crc, &msg->crc, sizeof(crc));
  
      if(crc == crc16_data(msg->sendcmd, len, 0)) {
        /* Start the server process with the incoming command. */
        process_start(&shell_sendcmd_server_process, msg->sendcmd);
      }
    }
  }
  static const struct unicast_callbacks unicast_callbacks = { recv_uc };
  /*---------------------------------------------------------------------------*/
  void
  shell_rime_sendcmd_init(void)
  {
    unicast_open(&uc, SHELL_RIME_CHANNEL_SENDCMD, &unicast_callbacks);
    shell_register_command(&sendcmd_command);
  }
  /*---------------------------------------------------------------------------*/
  