api_msg.c

《嵌入式网络系统设计-基于Atmel ARM7 系列》这个本书的光盘资料

/*
 * 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 <[e-mail]>
 *
 */

#include "lwip/opt.h"
#include "lwip/arch.h"
#include "lwip/api_msg.h"
#include "lwip/memp.h"
#include "lwip/sys.h"
#include "lwip/tcpip.h"

#if LWIP_RAW
static u8_t
recv_raw(void *arg, struct raw_pcb *pcb, struct pbuf *p,
    struct ip_addr *addr)
{
  struct netbuf *buf;
  struct netconn *conn;

  conn = arg;
  if (!conn) return 0;

  if (conn->recvmbox != SYS_MBOX_NULL) {
    if (!(buf = memp_malloc(MEMP_NETBUF))) {
      return 0;
    }
    pbuf_ref(p);
    buf->p = p;
    buf->ptr = p;
    buf->fromaddr = addr;
    buf->fromport = pcb->protocol;

    conn->recv_avail += p->tot_len;
    /* Register event with callback */
    if (conn->callback)
        (*conn->callback)(conn, NETCONN_EVT_RCVPLUS, p->tot_len);
    sys_mbox_post(conn->recvmbox, buf);
  }

  return 0; /* do not eat the packet */
}
#endif
#if LWIP_UDP
static void
recv_udp(void *arg, struct udp_pcb *pcb, struct pbuf *p,
   struct ip_addr *addr, u16_t port)
{
  struct netbuf *buf;
  struct netconn *conn;

  conn = arg;
  
  if (conn == NULL) {
    pbuf_free(p);
    return;
  }
  if (conn->recvmbox != SYS_MBOX_NULL) {
    buf = memp_malloc(MEMP_NETBUF);
    if (buf == NULL) {
      pbuf_free(p);
      return;
    } else {
      buf->p = p;
      buf->ptr = p;
      buf->fromaddr = addr;
      buf->fromport = port;
    }

  conn->recv_avail += p->tot_len;
    /* Register event with callback */
    if (conn->callback)
        (*conn->callback)(conn, NETCONN_EVT_RCVPLUS, p->tot_len);
    sys_mbox_post(conn->recvmbox, buf);
  }
}
#endif /* LWIP_UDP */
#if LWIP_TCP

static err_t
recv_tcp(void *arg, struct tcp_pcb *pcb, struct pbuf *p, err_t err)
{
  struct netconn *conn;
  u16_t len;
  
  conn = arg;

  if (conn == NULL) {
    pbuf_free(p);
    return ERR_VAL;
  }

  if (conn->recvmbox != SYS_MBOX_NULL) {
        
    conn->err = err;
    if (p != NULL) {
        len = p->tot_len;
        conn->recv_avail += len;
    }
    else
        len = 0;
    /* Register event with callback */
    if (conn->callback)
        (*conn->callback)(conn, NETCONN_EVT_RCVPLUS, len);
    sys_mbox_post(conn->recvmbox, p);
  }  
  return ERR_OK;
}


static err_t
poll_tcp(void *arg, struct tcp_pcb *pcb)
{
  struct netconn *conn;

  conn = arg;
  if (conn != NULL &&
     (conn->state == NETCONN_WRITE || conn->state == NETCONN_CLOSE) &&
     conn->sem != SYS_SEM_NULL) {
    sys_sem_signal(conn->sem);
  }
  return ERR_OK;
}

static err_t
sent_tcp(void *arg, struct tcp_pcb *pcb, u16_t len)
{
  struct netconn *conn;

  conn = arg;
  if (conn != NULL && conn->sem != SYS_SEM_NULL) {
    sys_sem_signal(conn->sem);
  }

  if (conn && conn->callback)
      if (tcp_sndbuf(conn->pcb.tcp) > TCP_SNDLOWAT)
          (*conn->callback)(conn, NETCONN_EVT_SENDPLUS, len);
  
  return ERR_OK;
}

static void
err_tcp(void *arg, err_t err)
{
  struct netconn *conn;

  conn = arg;

  conn->pcb.tcp = NULL;

  
  conn->err = err;
  if (conn->recvmbox != SYS_MBOX_NULL) {
    /* Register event with callback */
    if (conn->callback)
      (*conn->callback)(conn, NETCONN_EVT_RCVPLUS, 0);
    sys_mbox_post(conn->recvmbox, NULL);
  }
  if (conn->mbox != SYS_MBOX_NULL) {
    sys_mbox_post(conn->mbox, NULL);
  }
  if (conn->acceptmbox != SYS_MBOX_NULL) {
     /* Register event with callback */
    if (conn->callback)
      (*conn->callback)(conn, NETCONN_EVT_RCVPLUS, 0);
    sys_mbox_post(conn->acceptmbox, NULL);
  }
  if (conn->sem != SYS_SEM_NULL) {
    sys_sem_signal(conn->sem);
  }
}

static void
setup_tcp(struct netconn *conn)
{
  struct tcp_pcb *pcb;
  
  pcb = conn->pcb.tcp;
  tcp_arg(pcb, conn);
  tcp_recv(pcb, recv_tcp);
  tcp_sent(pcb, sent_tcp);
  tcp_poll(pcb, poll_tcp, 4);
  tcp_err(pcb, err_tcp);
}

static err_t
accept_function(void *arg, struct tcp_pcb *newpcb, err_t err)
{
  sys_mbox_t mbox;
  struct netconn *newconn;
  struct netconn *conn;
  
#if API_MSG_DEBUG
#if TCP_DEBUG
  tcp_debug_print_state(newpcb->state);
#endif /* TCP_DEBUG */
#endif /* API_MSG_DEBUG */
  conn = (struct netconn *)arg;
  mbox = conn->acceptmbox;
  newconn = memp_malloc(MEMP_NETCONN);
  if (newconn == NULL) {
    return ERR_MEM;
  }
  newconn->recvmbox = sys_mbox_new();
  if (newconn->recvmbox == SYS_MBOX_NULL) {
    memp_free(MEMP_NETCONN, newconn);
    return ERR_MEM;
  }
  newconn->mbox = sys_mbox_new();
  if (newconn->mbox == SYS_MBOX_NULL) {
    sys_mbox_free(newconn->recvmbox);
    memp_free(MEMP_NETCONN, newconn);
    return ERR_MEM;
  }
  newconn->sem = sys_sem_new(0);
  if (newconn->sem == SYS_SEM_NULL) {
    sys_mbox_free(newconn->recvmbox);
    sys_mbox_free(newconn->mbox);
    memp_free(MEMP_NETCONN, newconn);
    return ERR_MEM;
  }
  /* Allocations were OK, setup the PCB etc */
  newconn->type = NETCONN_TCP;
  newconn->pcb.tcp = newpcb;
  setup_tcp(newconn);
  newconn->acceptmbox = SYS_MBOX_NULL;
  newconn->err = err;
  /* Register event with callback */
  if (conn->callback)
  {
    (*conn->callback)(conn, NETCONN_EVT_RCVPLUS, 0);
  }
  /* We have to set the callback here even though
   * the new socket is unknown. Mark the socket as -1. */
  newconn->callback = conn->callback;
  newconn->socket = -1;
  newconn->recv_avail = 0;
  
  sys_mbox_post(mbox, newconn);
  return ERR_OK;
}
#endif /* LWIP_TCP */

static void
do_newconn(struct api_msg_msg *msg)
{
   if(msg->conn->pcb.tcp != NULL) {
   /* This "new" connection already has a PCB allocated. */
   /* Is this an error condition? Should it be deleted? 
      We currently just are happy and return. */
     sys_mbox_post(msg->conn->mbox, NULL);
     return;
   }

   msg->conn->err = ERR_OK;

   /* Allocate a PCB for this connection */
   switch(msg->conn->type) {
#if LWIP_RAW
   case NETCONN_RAW:
      msg->conn->pcb.raw = raw_new(msg->msg.bc.port); /* misusing the port field */
      raw_recv(msg->conn->pcb.raw, recv_raw, msg->conn);
     break;
#endif
#if LWIP_UDP
   case NETCONN_UDPLITE:
      msg->conn->pcb.udp = udp_new();
      if(msg->conn->pcb.udp == NULL) {
         msg->conn->err = ERR_MEM;
         break;
      }
      udp_setflags(msg->conn->pcb.udp, UDP_FLAGS_UDPLITE);
      udp_recv(msg->conn->pcb.udp, recv_udp, msg->conn);
      break;
   case NETCONN_UDPNOCHKSUM:
      msg->conn->pcb.udp = udp_new();
      if(msg->conn->pcb.udp == NULL) {
         msg->conn->err = ERR_MEM;
         break;
      }
      udp_setflags(msg->conn->pcb.udp, UDP_FLAGS_NOCHKSUM);
      udp_recv(msg->conn->pcb.udp, recv_udp, msg->conn);
      break;
   case NETCONN_UDP:
      msg->conn->pcb.udp = udp_new();
      if(msg->conn->pcb.udp == NULL) {
         msg->conn->err = ERR_MEM;
         break;
      }
      udp_recv(msg->conn->pcb.udp, recv_udp, msg->conn);
      break;
#endif /* LWIP_UDP */
#if LWIP_TCP
   case NETCONN_TCP:
      msg->conn->pcb.tcp = tcp_new();
      if(msg->conn->pcb.tcp == NULL) {
         msg->conn->err = ERR_MEM;
         break;
      }
      setup_tcp(msg->conn);
      break;
#endif
   }
   
  
  sys_mbox_post(msg->conn->mbox, NULL);
}


static void
do_delconn(struct api_msg_msg *msg)
{
  if (msg->conn->pcb.tcp != NULL) {
    switch (msg->conn->type) {
#if LWIP_RAW
    case NETCONN_RAW:
      raw_remove(msg->conn->pcb.raw);
      break;
#endif
#if LWIP_UDP
    case NETCONN_UDPLITE:
      /* FALLTHROUGH */
    case NETCONN_UDPNOCHKSUM:
      /* FALLTHROUGH */
    case NETCONN_UDP:
      msg->conn->pcb.udp->recv_arg = NULL;
      udp_remove(msg->conn->pcb.udp);
      break;
#endif /* LWIP_UDP */
#if LWIP_TCP      
    case NETCONN_TCP:
      if (msg->conn->pcb.tcp->state == LISTEN) {
  tcp_arg(msg->conn->pcb.tcp, NULL);
  tcp_accept(msg->conn->pcb.tcp, NULL);  
  tcp_close(msg->conn->pcb.tcp);
      } else {
  tcp_arg(msg->conn->pcb.tcp, NULL);
  tcp_sent(msg->conn->pcb.tcp, NULL);
  tcp_recv(msg->conn->pcb.tcp, NULL);  
  tcp_poll(msg->conn->pcb.tcp, NULL, 0);
  tcp_err(msg->conn->pcb.tcp, NULL);
  if (tcp_close(msg->conn->pcb.tcp) != ERR_OK) {
    tcp_abort(msg->conn->pcb.tcp);
  }
      }
#endif
    default:  
    break;
    }
  }
  /* Trigger select() in socket layer */
  if (msg->conn->callback)
  {
      (*msg->conn->callback)(msg->conn, NETCONN_EVT_RCVPLUS, 0);
      (*msg->conn->callback)(msg->conn, NETCONN_EVT_SENDPLUS, 0);
  }
  
  if (msg->conn->mbox != SYS_MBOX_NULL) {
    sys_mbox_post(msg->conn->mbox, NULL);
  }
}

static void
do_bind(struct api_msg_msg *msg)
{
  if (msg->conn->pcb.tcp == NULL) {
    switch (msg->conn->type) {
#if LWIP_RAW
    case NETCONN_RAW:
      msg->conn->pcb.raw = raw_new(msg->msg.bc.port); /* misusing the port field as protocol */
      raw_recv(msg->conn->pcb.raw, recv_raw, msg->conn);
      break;
#endif
#if LWIP_UDP
    case NETCONN_UDPLITE:
      msg->conn->pcb.udp = udp_new();
      udp_setflags(msg->conn->pcb.udp, UDP_FLAGS_UDPLITE);