api_msg.c

LWIP在STM32裸机上的移植

/**
 * @file
 * Sequential API Internal module
 *
 */

/*
 * 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"

#if LWIP_NETCONN /* don't build if not configured for use in lwipopts.h */

#include "lwip/api_msg.h"

#include "lwip/ip.h"
#include "lwip/udp.h"
#include "lwip/tcp.h"
#include "lwip/raw.h"

#include "lwip/memp.h"
#include "lwip/tcpip.h"
#include "lwip/igmp.h"
#include "lwip/dns.h"

#include <string.h>

/* forward declarations */
#if LWIP_TCP
static err_t do_writemore(struct netconn *conn);
static void do_close_internal(struct netconn *conn);
#endif

#if LWIP_RAW
/**
 * Receive callback function for RAW netconns.
 * Doesn't 'eat' the packet, only references it and sends it to
 * conn->recvmbox
 *
 * @see raw.h (struct raw_pcb.recv) for parameters and return value
 */
static u8_t
recv_raw(void *arg, struct raw_pcb *pcb, struct pbuf *p,
    struct ip_addr *addr)
{
  struct pbuf *q;
  struct netbuf *buf;
  struct netconn *conn;
#if LWIP_SO_RCVBUF
  int recv_avail;
#endif /* LWIP_SO_RCVBUF */

  LWIP_UNUSED_ARG(addr);
  conn = arg;

#if LWIP_SO_RCVBUF
  SYS_ARCH_GET(conn->recv_avail, recv_avail);
  if ((conn != NULL) && (conn->recvmbox != SYS_MBOX_NULL) &&
      ((recv_avail + (int)(p->tot_len)) <= conn->recv_bufsize)) {
#else  /* LWIP_SO_RCVBUF */
  if ((conn != NULL) && (conn->recvmbox != SYS_MBOX_NULL)) {
#endif /* LWIP_SO_RCVBUF */
    /* copy the whole packet into new pbufs */
    q = pbuf_alloc(PBUF_RAW, p->tot_len, PBUF_RAM);
    if(q != NULL) {
      if (pbuf_copy(q, p) != ERR_OK) {
        pbuf_free(q);
        q = NULL;
      }
    }

    if(q != NULL) {
      buf = memp_malloc(MEMP_NETBUF);
      if (buf == NULL) {
        pbuf_free(q);
        return 0;
      }

      buf->p = q;
      buf->ptr = q;
      buf->addr = &(((struct ip_hdr*)(q->payload))->src);
      buf->port = pcb->protocol;

      if (sys_mbox_trypost(conn->recvmbox, buf) != ERR_OK) {
        netbuf_delete(buf);
        return 0;
      } else {
        SYS_ARCH_INC(conn->recv_avail, q->tot_len);
        /* Register event with callback */
        API_EVENT(conn, NETCONN_EVT_RCVPLUS, q->tot_len);
      }
    }
  }

  return 0; /* do not eat the packet */
}
#endif /* LWIP_RAW*/

#if LWIP_UDP
/**
 * Receive callback function for UDP netconns.
 * Posts the packet to conn->recvmbox or deletes it on memory error.
 *
 * @see udp.h (struct udp_pcb.recv) for parameters
 */
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;
#if LWIP_SO_RCVBUF
  int recv_avail;
#endif /* LWIP_SO_RCVBUF */

  LWIP_UNUSED_ARG(pcb); /* only used for asserts... */
  LWIP_ASSERT("recv_udp must have a pcb argument", pcb != NULL);
  LWIP_ASSERT("recv_udp must have an argument", arg != NULL);
  conn = arg;
  LWIP_ASSERT("recv_udp: recv for wrong pcb!", conn->pcb.udp == pcb);

#if LWIP_SO_RCVBUF
  SYS_ARCH_GET(conn->recv_avail, recv_avail);
  if ((conn == NULL) || (conn->recvmbox == SYS_MBOX_NULL) ||
      ((recv_avail + (int)(p->tot_len)) > conn->recv_bufsize)) {
#else  /* LWIP_SO_RCVBUF */
  if ((conn == NULL) || (conn->recvmbox == SYS_MBOX_NULL)) {
#endif /* LWIP_SO_RCVBUF */
    pbuf_free(p);
    return;
  }

  buf = memp_malloc(MEMP_NETBUF);
  if (buf == NULL) {
    pbuf_free(p);
    return;
  } else {
    buf->p = p;
    buf->ptr = p;
    buf->addr = addr;
    buf->port = port;
  }

  if (sys_mbox_trypost(conn->recvmbox, buf) != ERR_OK) {
    netbuf_delete(buf);
    return;
  } else {
    SYS_ARCH_INC(conn->recv_avail, p->tot_len);
    /* Register event with callback */
    API_EVENT(conn, NETCONN_EVT_RCVPLUS, p->tot_len);
  }
}
#endif /* LWIP_UDP */

#if LWIP_TCP
/**
 * Receive callback function for TCP netconns.
 * Posts the packet to conn->recvmbox, but doesn't delete it on errors.
 *
 * @see tcp.h (struct tcp_pcb.recv) for parameters and return value
 */
static err_t
recv_tcp(void *arg, struct tcp_pcb *pcb, struct pbuf *p, err_t err)
{
  struct netconn *conn;
  u16_t len;

  LWIP_UNUSED_ARG(pcb);
  LWIP_ASSERT("recv_tcp must have a pcb argument", pcb != NULL);
  LWIP_ASSERT("recv_tcp must have an argument", arg != NULL);
  conn = arg;
  LWIP_ASSERT("recv_tcp: recv for wrong pcb!", conn->pcb.tcp == pcb);

  if ((conn == NULL) || (conn->recvmbox == SYS_MBOX_NULL)) {
    return ERR_VAL;
  }

  conn->err = err;
  if (p != NULL) {
    len = p->tot_len;
    SYS_ARCH_INC(conn->recv_avail, len);
  } else {
    len = 0;
  }

  if (sys_mbox_trypost(conn->recvmbox, p) != ERR_OK) {
    return ERR_MEM;
  } else {
    /* Register event with callback */
    API_EVENT(conn, NETCONN_EVT_RCVPLUS, len);
  }

  return ERR_OK;
}

/**
 * Poll callback function for TCP netconns.
 * Wakes up an application thread that waits for a connection to close
 * or data to be sent. The application thread then takes the
 * appropriate action to go on.
 *
 * Signals the conn->sem.
 * netconn_close waits for conn->sem if closing failed.
 *
 * @see tcp.h (struct tcp_pcb.poll) for parameters and return value
 */
static err_t
poll_tcp(void *arg, struct tcp_pcb *pcb)
{
  struct netconn *conn = arg;

  LWIP_UNUSED_ARG(pcb);
  LWIP_ASSERT("conn != NULL", (conn != NULL));

  if (conn->state == NETCONN_WRITE) {
    do_writemore(conn);
  } else if (conn->state == NETCONN_CLOSE) {
    do_close_internal(conn);
  }

  return ERR_OK;
}

/**
 * Sent callback function for TCP netconns.
 * Signals the conn->sem and calls API_EVENT.
 * netconn_write waits for conn->sem if send buffer is low.
 *
 * @see tcp.h (struct tcp_pcb.sent) for parameters and return value
 */
static err_t
sent_tcp(void *arg, struct tcp_pcb *pcb, u16_t len)
{
  struct netconn *conn = arg;

  LWIP_UNUSED_ARG(pcb);
  LWIP_ASSERT("conn != NULL", (conn != NULL));

  if (conn->state == NETCONN_WRITE) {
    LWIP_ASSERT("conn->pcb.tcp != NULL", conn->pcb.tcp != NULL);
    do_writemore(conn);
  } else if (conn->state == NETCONN_CLOSE) {
    do_close_internal(conn);
  }

  if (conn) {
    if ((conn->pcb.tcp != NULL) && (tcp_sndbuf(conn->pcb.tcp) > TCP_SNDLOWAT)) {
      API_EVENT(conn, NETCONN_EVT_SENDPLUS, len);
    }
  }
  
  return ERR_OK;
}

/**
 * Error callback function for TCP netconns.
 * Signals conn->sem, posts to all conn mboxes and calls API_EVENT.
 * The application thread has then to decide what to do.
 *
 * @see tcp.h (struct tcp_pcb.err) for parameters
 */
static void
err_tcp(void *arg, err_t err)
{
  struct netconn *conn;

  conn = arg;
  LWIP_ASSERT("conn != NULL", (conn != NULL));

  conn->pcb.tcp = NULL;

  conn->err = err;
  if (conn->recvmbox != SYS_MBOX_NULL) {
    /* Register event with callback */
    API_EVENT(conn, NETCONN_EVT_RCVPLUS, 0);
    sys_mbox_post(conn->recvmbox, NULL);
  }
  if (conn->op_completed != SYS_SEM_NULL && conn->state == NETCONN_CONNECT) {
    conn->state = NETCONN_NONE;
    sys_sem_signal(conn->op_completed);
  }
  if (conn->acceptmbox != SYS_MBOX_NULL) {
    /* Register event with callback */
    API_EVENT(conn, NETCONN_EVT_RCVPLUS, 0);
    sys_mbox_post(conn->acceptmbox, NULL);
  }
  if ((conn->state == NETCONN_WRITE) || (conn->state == NETCONN_CLOSE)) {
    /* calling do_writemore/do_close_internal is not necessary
       since the pcb has already been deleted! */
    conn->state = NETCONN_NONE;
    /* wake up the waiting task */
    sys_sem_signal(conn->op_completed);
  }
}

/**
 * Setup a tcp_pcb with the correct callback function pointers
 * and their arguments.
 *
 * @param conn the TCP netconn to setup
 */
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);
}

/**
 * Accept callback function for TCP netconns.
 * Allocates a new netconn and posts that to conn->acceptmbox.
 *
 * @see tcp.h (struct tcp_pcb_listen.accept) for parameters and return value
 */
static err_t
accept_function(void *arg, struct tcp_pcb *newpcb, err_t err)
{
  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;

  LWIP_ERROR("accept_function: invalid conn->acceptmbox",
             conn->acceptmbox != SYS_MBOX_NULL, return ERR_VAL;);

  /* We have to set the callback here even though
   * the new socket is unknown. conn->socket is marked as -1. */
  newconn = netconn_alloc(conn->type, conn->callback);
  if (newconn == NULL) {
    return ERR_MEM;
  }
  newconn->pcb.tcp = newpcb;
  setup_tcp(newconn);
  newconn->err = err;

  if (sys_mbox_trypost(conn->acceptmbox, newconn) != ERR_OK) {
    /* When returning != ERR_OK, the connection is aborted in tcp_process(),
       so do nothing here! */
    newconn->pcb.tcp = NULL;
    netconn_free(newconn);
    return ERR_MEM;
  } else {
    /* Register event with callback */
    API_EVENT(conn, NETCONN_EVT_RCVPLUS, 0);
  }

  return ERR_OK;
}
#endif /* LWIP_TCP */

/**
 * Create a new pcb of a specific type.
 * Called from do_newconn().
 *
 * @param msg the api_msg_msg describing the connection type
 * @return msg->conn->err, but the return value is currently ignored
 */
static err_t
pcb_new(struct api_msg_msg *msg)
{
   msg->conn->err = ERR_OK;

   LWIP_ASSERT("pcb_new: pcb already allocated", msg->conn->pcb.tcp == NULL);

   /* Allocate a PCB for this connection */
   switch(NETCONNTYPE_GROUP(msg->conn->type)) {
#if LWIP_RAW
   case NETCONN_RAW:
     msg->conn->pcb.raw = raw_new(msg->msg.n.proto);
     if(msg->conn->pcb.raw == NULL) {
       msg->conn->err = ERR_MEM;