text: /*
   * 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>
   *
   * Improved by Marc Boucher <marc@mbsi.ca> and David Haas <dhaas@alum.rpi.edu>
   *
   */
  
  #include <string.h>
  /* #include <errno.h> */
  
  #include "lwip/opt.h"
  #include "lwip/api.h"
  #include "lwip/arch.h"
  #include "lwip/sys.h"
  
  #include "lwip/sockets.h"
  
  #define NUM_SOCKETS MEMP_NUM_NETCONN
  
  struct lwip_socket {
    struct netconn *conn;
    struct netbuf *lastdata;
    u16_t lastoffset;
    u16_t rcvevent;
    u16_t sendevent;
    u16_t  flags;
    int err;
  };
  
  struct lwip_select_cb
  {
      struct lwip_select_cb *next;
      fd_set *readset;
      fd_set *writeset;
      fd_set *exceptset;
      int sem_signalled;
      sys_sem_t sem;
  };
  
  static struct lwip_socket sockets[NUM_SOCKETS];
  static struct lwip_select_cb *select_cb_list = 0;
  
  static sys_sem_t socksem = 0;
  static sys_sem_t selectsem = 0;
  
  static void
  event_callback(struct netconn *conn, enum netconn_evt evt, u16_t len);
  
  static int err_to_errno_table[11] = {
      0,      /* ERR_OK    0      No error, everything OK. */
      ENOMEM,    /* ERR_MEM  -1      Out of memory error.     */
      ENOBUFS,    /* ERR_BUF  -2      Buffer error.            */
      ECONNABORTED,  /* ERR_ABRT -3      Connection aborted.      */
      ECONNRESET,    /* ERR_RST  -4      Connection reset.        */
      ESHUTDOWN,    /* ERR_CLSD -5      Connection closed.       */
      ENOTCONN,    /* ERR_CONN -6      Not connected.           */
      EINVAL,    /* ERR_VAL  -7      Illegal value.           */
      EIO,    /* ERR_ARG  -8      Illegal argument.        */
      EHOSTUNREACH,  /* ERR_RTE  -9      Routing problem.         */
      EADDRINUSE    /* ERR_USE  -10     Address in use.          */
  };
  
  #define ERR_TO_ERRNO_TABLE_SIZE \
    (sizeof(err_to_errno_table)/sizeof(err_to_errno_table[0]))
  
  #define err_to_errno(err) \
    (-(err) >= 0 && -(err) < ERR_TO_ERRNO_TABLE_SIZE ? \
      err_to_errno_table[-(err)] : EIO)
  
  #ifdef ERRNO
  #define set_errno(err) errno = (err)
  #else
  #define set_errno(err)
  #endif
  
  #define sock_set_errno(sk, e) do { \
        sk->err = (e); \
        set_errno(sk->err); \
  } while (0)
  
  
  static struct lwip_socket *
  get_socket(int s)
  {
    struct lwip_socket *sock;
  
    if ((s < 0) || (s > NUM_SOCKETS)) {
      LWIP_DEBUGF(SOCKETS_DEBUG, ("get_socket(%d): invalid\n", s));
      set_errno(EBADF);
      return NULL;
    }
  
    sock = &sockets[s];
  
    if (!sock->conn) {
      LWIP_DEBUGF(SOCKETS_DEBUG, ("get_socket(%d): not active\n", s));
      set_errno(EBADF);
      return NULL;
    }
  
    return sock;
  }
  
  static int
  alloc_socket(struct netconn *newconn)
  {
    int i;
  
    if (!socksem)
        socksem = sys_sem_new(1);
  
    /* Protect socket array */
    sys_sem_wait(socksem);
  
    /* allocate a new socket identifier */
    for(i = 0; i < NUM_SOCKETS; ++i) {
      if (!sockets[i].conn) {
        sockets[i].conn = newconn;
        sockets[i].lastdata = NULL;
        sockets[i].lastoffset = 0;
        sockets[i].rcvevent = 0;
        sockets[i].sendevent = 1; /* TCP send buf is empty */
        sockets[i].flags = 0;
        sockets[i].err = 0;
        sys_sem_signal(socksem);
        return i;
      }
    }
    sys_sem_signal(socksem);
    return -1;
  }
  
  int
  lwip_accept(int s, struct sockaddr *addr, socklen_t *addrlen)
  {
    struct lwip_socket *sock;
    struct netconn *newconn;
    struct ip_addr naddr;
    u16_t port;
    int newsock;
    struct sockaddr_in sin;
  
    LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_accept(%d)...\n", s));
    sock = get_socket(s);
    if (!sock) {
      set_errno(EBADF);
      return -1;
    }
  
    newconn = netconn_accept(sock->conn);
  
    /* get the IP address and port of the remote host */
    netconn_peer(newconn, &naddr, &port);
  
    memset(&sin, 0, sizeof(sin));
    sin.sin_len = sizeof(sin);
    sin.sin_family = AF_INET;
    sin.sin_port = htons(port);
    sin.sin_addr.s_addr = naddr.addr;
  
    if (*addrlen > sizeof(sin))
        *addrlen = sizeof(sin);
  
    memcpy(addr, &sin, *addrlen);
  
    newsock = alloc_socket(newconn);
    if (newsock == -1) {
      netconn_delete(newconn);
    sock_set_errno(sock, ENOBUFS);
    return -1;
    }
    newconn->callback = event_callback;
    sock = get_socket(newsock);
  
    sys_sem_wait(socksem);
    sock->rcvevent += -1 - newconn->socket;
    newconn->socket = newsock;
    sys_sem_signal(socksem);
  
    LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_accept(%d) returning new sock=%d addr=", s, newsock));
    ip_addr_debug_print(SOCKETS_DEBUG, &naddr);
    LWIP_DEBUGF(SOCKETS_DEBUG, (" port=%u\n", port));
  
    sock_set_errno(sock, 0);
    return newsock;
  }
  
  int
  lwip_bind(int s, struct sockaddr *name, socklen_t namelen)
  {
    struct lwip_socket *sock;
    struct ip_addr local_addr;
    u16_t local_port;
    err_t err;
  
    sock = get_socket(s);
    if (!sock) {
      set_errno(EBADF);
      return -1;
    }
  
    local_addr.addr = ((struct sockaddr_in *)name)->sin_addr.s_addr;
    local_port = ((struct sockaddr_in *)name)->sin_port;
  
    LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_bind(%d, addr=", s));
    ip_addr_debug_print(SOCKETS_DEBUG, &local_addr);
    LWIP_DEBUGF(SOCKETS_DEBUG, (" port=%u)\n", ntohs(local_port)));
  
    err = netconn_bind(sock->conn, &local_addr, ntohs(local_port));
  
    if (err != ERR_OK) {
      LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_bind(%d) failed, err=%d\n", s, err));
      sock_set_errno(sock, err_to_errno(err));
      return -1;
    }
  
    LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_bind(%d) succeeded\n", s));
    sock_set_errno(sock, 0);
    return 0;
  }
  
  int
  lwip_close(int s)
  {
    struct lwip_socket *sock;
  
    LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_close(%d)\n", s));
    if (!socksem)
        socksem = sys_sem_new(1);
  
    /* We cannot allow multiple closes of the same socket. */
    sys_sem_wait(socksem);
  
    sock = get_socket(s);
    if (!sock) {
        sys_sem_signal(socksem);
        set_errno(EBADF);
        return -1;
    }
  
    netconn_delete(sock->conn);
    if (sock->lastdata) {
      netbuf_delete(sock->lastdata);
    }
    sock->lastdata = NULL;
    sock->lastoffset = 0;
    sock->conn = NULL;
    sys_sem_signal(socksem);
    sock_set_errno(sock, 0);
    return 0;
  }
  
  int
  lwip_connect(int s, struct sockaddr *name, socklen_t namelen)
  {
    struct lwip_socket *sock;
    err_t err;
  
    sock = get_socket(s);
    if (!sock) {
      set_errno(EBADF);
      return -1;
    }
  
    if (((struct sockaddr_in *)name)->sin_family == AF_UNSPEC) {
      LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_connect(%d, AF_UNSPEC)\n", s));
      err = netconn_disconnect(sock->conn);
    } else {
      struct ip_addr remote_addr;
      u16_t remote_port;
  
      remote_addr.addr = ((struct sockaddr_in *)name)->sin_addr.s_addr;
      remote_port = ((struct sockaddr_in *)name)->sin_port;
  
      LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_connect(%d, addr=", s));
      ip_addr_debug_print(SOCKETS_DEBUG, &remote_addr);
      LWIP_DEBUGF(SOCKETS_DEBUG, (" port=%u)\n", ntohs(remote_port)));
  
      err = netconn_connect(sock->conn, &remote_addr, ntohs(remote_port));
     }
  
    if (err != ERR_OK) {
      LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_connect(%d) failed, err=%d\n", s, err));
      sock_set_errno(sock, err_to_errno(err));
      return -1;
    }
  
    LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_connect(%d) succeeded\n", s));
    sock_set_errno(sock, 0);
    return 0;
  }
  
  int
  lwip_listen(int s, int backlog)
  {
    struct lwip_socket *sock;
    err_t err;
  
    LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_listen(%d, backlog=%d)\n", s, backlog));
    sock = get_socket(s);
    if (!sock) {
      set_errno(EBADF);
      return -1;
    }
  
    err = netconn_listen(sock->conn);
  
    if (err != ERR_OK) {
      LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_listen(%d) failed, err=%d\n", s, err));
      sock_set_errno(sock, err_to_errno(err));
      return -1;
    }
  
    sock_set_errno(sock, 0);
    return 0;
  }
  
  int
  lwip_recvfrom(int s, void *mem, int len, unsigned int flags,
          struct sockaddr *from, socklen_t *fromlen)
  {
    struct lwip_socket *sock;
    struct netbuf *buf;
    u16_t buflen, copylen;
    struct ip_addr *addr;
    u16_t port;
  
  
    LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_recvfrom(%d, %p, %d, 0x%x, ..)\n", s, mem, len, flags));
    sock = get_socket(s);
    if (!sock) {
      set_errno(EBADF);
      return -1;
    }
  
    /* Check if there is data left from the last recv operation. */
    if (sock->lastdata) {
      buf = sock->lastdata;
    } else {
      /* If this is non-blocking call, then check first */
      if (((flags & MSG_DONTWAIT) || (sock->flags & O_NONBLOCK))
    && !sock->rcvevent)
      {
        LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_recvfrom(%d): returning EWOULDBLOCK\n", s));
        sock_set_errno(sock, EWOULDBLOCK);
        return -1;
      }
  
      /* No data was left from the previous operation, so we try to get
         some from the network. */
      buf = netconn_recv(sock->conn);
  
      if (!buf) {
        /* We should really do some error checking here. */
        LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_recvfrom(%d): buf == NULL!\n", s));
        sock_set_errno(sock, 0);
        return 0;
      }
    }
  
    buflen = netbuf_len(buf);
  
    buflen -= sock->lastoffset;
  
    if (len > buflen) {
      copylen = buflen;
    } else {
      copylen = len;
    }
  
    /* copy the contents of the received buffer into
       the supplied memory pointer mem */
    netbuf_copy_partial(buf, mem, copylen, sock->lastoffset);
  
    /* Check to see from where the data was. */
    if (from && fromlen) {
      struct sockaddr_in sin;
  
      addr = netbuf_fromaddr(buf);
      port = netbuf_fromport(buf);
  
      memset(&sin, 0, sizeof(sin));
      sin.sin_len = sizeof(sin);
      sin.sin_family = AF_INET;
      sin.sin_port = htons(port);
      sin.sin_addr.s_addr = addr->addr;
  
      if (*fromlen > sizeof(sin))
        *fromlen = sizeof(sin);
  
      memcpy(from, &sin, *fromlen);
  
      LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_recvfrom(%d): addr=", s));
      ip_addr_debug_print(SOCKETS_DEBUG, addr);
      LWIP_DEBUGF(SOCKETS_DEBUG, (" port=%u len=%u\n", port, copylen));
    } else {
  #if SOCKETS_DEBUG
      addr = netbuf_fromaddr(buf);
      port = netbuf_fromport(buf);
  
      LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_recvfrom(%d): addr=", s));
      ip_addr_debug_print(SOCKETS_DEBUG, addr);
      LWIP_DEBUGF(SOCKETS_DEBUG, (" port=%u len=%u\n", port, copylen));
  #endif
  
    }
  
    /* If this is a TCP socket, check if there is data left in the
       buffer. If so, it should be saved in the sock structure for next
       time around. */
    if (netconn_type(sock->conn) == NETCONN_TCP && buflen - copylen > 0) {
      sock->lastdata = buf;
      sock->lastoffset += copylen;
    } else {
      sock->lastdata = NULL;
      sock->lastoffset = 0;
      netbuf_delete(buf);
    }
  
  
    sock_set_errno(sock, 0);
    return copylen;
  }
  
  int
  lwip_read(int s, void *mem, int len)
  {
    return lwip_recvfrom(s, mem, len, 0, NULL, NULL);
  }
  
  int
  lwip_recv(int s, void *mem, int len, unsigned int flags)
  {
    return lwip_recvfrom(s, mem, len, flags, NULL, NULL);
  }
  
  int
  lwip_send(int s, void *data, int size, unsigned int flags)
  {
    struct lwip_socket *sock;
    struct netbuf *buf;
    err_t err;
  
    LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_send(%d, data=%p, size=%d, flags=0x%x)\n", s, data, size, flags));
  
    sock = get_socket(s);
    if (!sock) {
      set_errno(EBADF);
      return -1;
    }
  
    switch (netconn_type(sock->conn)) {
    case NETCONN_RAW:
    case NETCONN_UDP:
    case NETCONN_UDPLITE:
    case NETCONN_UDPNOCHKSUM:
      /* create a buffer */
      buf = netbuf_new();
  
      if (!buf) {
        LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_send(%d) ENOBUFS\n", s));
        sock_set_errno(sock, ENOBUFS);
        return -1;
      }
  
      /* make the buffer point to the data that should
         be sent */
      netbuf_ref(buf, data, size);
  
      /* send the data */
      err = netconn_send(sock->conn, buf);
  
      /* deallocated the buffer */
      netbuf_delete(buf);
      break;
    case NETCONN_TCP:
      err = netconn_write(sock->conn, data, size, NETCONN_COPY);
      break;
    default:
      err = ERR_ARG;
      break;
    }
    if (err != ERR_OK) {
      LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_send(%d) err=%d\n", s, err));
      sock_set_errno(sock, err_to_errno(err));
      return -1;
    }
  
    LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_send(%d) ok size=%d\n", s, size));
    sock_set_errno(sock, 0);
    return size;
  }
  
  int
  lwip_sendto(int s, void *data, int size, unsigned int flags,
         struct sockaddr *to, socklen_t tolen)
  {
    struct lwip_socket *sock;
    struct ip_addr remote_addr, addr;
    u16_t remote_port, port;
    int ret,connected;
  
    sock = get_socket(s);
    if (!sock) {
      set_errno(EBADF);
      return -1;
    }
  
    /* get the peer if currently connected */
    connected = (netconn_peer(sock->conn, &addr, &port) == ERR_OK);
  
    remote_addr.addr = ((struct sockaddr_in *)to)->sin_addr.s_addr;
    remote_port = ((struct sockaddr_in *)to)->sin_port;
  
    LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_sendto(%d, data=%p, size=%d, flags=0x%x to=", s, data, size, flags));
    ip_addr_debug_print(SOCKETS_DEBUG, &remote_addr);
    LWIP_DEBUGF(SOCKETS_DEBUG, (" port=%u\n", ntohs(remote_port)));
  
    netconn_connect(sock->conn, &remote_addr, ntohs(remote_port));
  
    ret = lwip_send(s, data, size, flags);
  
    /* reset the remote address and port number
       of the connection */
    if (connected)
      netconn_connect(sock->conn, &addr, port);
    else
    netconn_disconnect(sock->conn);
    return ret;
  }
  
  int
  lwip_socket(int domain, int type, int protocol)
  {
    struct netconn *conn;
    int i;
  
    /* create a netconn */
    switch (type) {
    case SOCK_RAW:
      conn = netconn_new_with_proto_and_callback(NETCONN_RAW, protocol, event_callback);
      LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_socket(%s, SOCK_RAW, %d) = ", domain == PF_INET ? "PF_INET" : "UNKNOWN", protocol));
      break;
    case SOCK_DGRAM:
      conn = netconn_new_with_callback(NETCONN_UDP, event_callback);
      LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_socket(%s, SOCK_DGRAM, %d) = ", domain == PF_INET ? "PF_INET" : "UNKNOWN", protocol));
      break;
    case SOCK_STREAM:
      conn = netconn_new_with_callback(NETCONN_TCP, event_callback);
      LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_socket(%s, SOCK_STREAM, %d) = ", domain == PF_INET ? "PF_INET" : "UNKNOWN", protocol));
      break;
    default:
      LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_socket(%d, %d/UNKNOWN, %d) = -1\n", domain, type, protocol));
      set_errno(EINVAL);
      return -1;
    }
  
    if (!conn) {
      LWIP_DEBUGF(SOCKETS_DEBUG, ("-1 / ENOBUFS (could not create netconn)\n"));
      set_errno(ENOBUFS);
      return -1;
    }
  
    i = alloc_socket(conn);
  
    if (i == -1) {
      netconn_delete(conn);
    set_errno(ENOBUFS);
    return -1;
    }
    conn->socket = i;
    LWIP_DEBUGF(SOCKETS_DEBUG, ("%d\n", i));
    set_errno(0);
    return i;
  }
  
  int
  lwip_write(int s, void *data, int size)
  {
     return lwip_send(s, data, size, 0);
  }
  
  
  static int
  lwip_selscan(int maxfdp1, fd_set *readset, fd_set *writeset, fd_set *exceptset)
  {
      int i, nready = 0;
      fd_set lreadset, lwriteset, lexceptset;
      struct lwip_socket *p_sock;
  
      FD_ZERO(&lreadset);
      FD_ZERO(&lwriteset);
      FD_ZERO(&lexceptset);
  
      /* Go through each socket in each list to count number of sockets which
         currently match */
      for(i = 0; i < maxfdp1; i++)
      {
          if (FD_ISSET(i, readset))
          {
              /* See if netconn of this socket is ready for read */
              p_sock = get_socket(i);
              if (p_sock && (p_sock->lastdata || p_sock->rcvevent))
              {
                  FD_SET(i, &lreadset);
  		LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_selscan: fd=%d ready for reading\n", i));
                  nready++;
              }
          }
          if (FD_ISSET(i, writeset))
          {
              /* See if netconn of this socket is ready for write */
              p_sock = get_socket(i);
              if (p_sock && p_sock->sendevent)
              {
                  FD_SET(i, &lwriteset);
  		LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_selscan: fd=%d ready for writing\n", i));
                  nready++;
              }
          }
      }
      *readset = lreadset;
      *writeset = lwriteset;
      FD_ZERO(exceptset);
  
      return nready;
  }
  
  
  
  int
  lwip_select(int maxfdp1, fd_set *readset, fd_set *writeset, fd_set *exceptset,
                 struct timeval *timeout)
  {
      int i;
      int nready;
      fd_set lreadset, lwriteset, lexceptset;
      u32_t msectimeout;
      struct lwip_select_cb select_cb;
      struct lwip_select_cb *p_selcb;
  
      LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_select(%d, %p, %p, %p, tvsec=%ld tvusec=%ld)\n", maxfdp1, (void *)readset, (void *) writeset, (void *) exceptset, timeout ? timeout->tv_sec : -1L, timeout ? timeout->tv_usec : -1L));
  
      select_cb.next = 0;
      select_cb.readset = readset;
      select_cb.writeset = writeset;
      select_cb.exceptset = exceptset;
      select_cb.sem_signalled = 0;
  
      /* Protect ourselves searching through the list */
      if (!selectsem)
          selectsem = sys_sem_new(1);
      sys_sem_wait(selectsem);
  
      if (readset)
          lreadset = *readset;
      else
          FD_ZERO(&lreadset);
      if (writeset)
          lwriteset = *writeset;
      else
          FD_ZERO(&lwriteset);
      if (exceptset)
          lexceptset = *exceptset;
      else
          FD_ZERO(&lexceptset);
  
      /* Go through each socket in each list to count number of sockets which
         currently match */
      nready = lwip_selscan(maxfdp1, &lreadset, &lwriteset, &lexceptset);
  
      /* If we don't have any current events, then suspend if we are supposed to */
      if (!nready)
      {
          if (timeout && timeout->tv_sec == 0 && timeout->tv_usec == 0)
          {
              sys_sem_signal(selectsem);
              if (readset)
                  FD_ZERO(readset);
              if (writeset)
                  FD_ZERO(writeset);
              if (exceptset)
                  FD_ZERO(exceptset);
  
  	    LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_select: no timeout, returning 0\n"));
  	    set_errno(0);
  
              return 0;
          }
  
          /* add our semaphore to list */
          /* We don't actually need any dynamic memory. Our entry on the
           * list is only valid while we are in this function, so it's ok
           * to use local variables */
  
          select_cb.sem = sys_sem_new(0);
          /* Note that we are still protected */
          /* Put this select_cb on top of list */
          select_cb.next = select_cb_list;
          select_cb_list = &select_cb;
  
          /* Now we can safely unprotect */
          sys_sem_signal(selectsem);
  
          /* Now just wait to be woken */
          if (timeout == 0)
              /* Wait forever */
              msectimeout = 0;
          else
              msectimeout =  ((timeout->tv_sec * 1000) + ((timeout->tv_usec + 500)/1000));
  
          i = sys_sem_wait_timeout(select_cb.sem, msectimeout);
  
          /* Take us off the list */
          sys_sem_wait(selectsem);
          if (select_cb_list == &select_cb)
              select_cb_list = select_cb.next;
          else
              for (p_selcb = select_cb_list; p_selcb; p_selcb = p_selcb->next)
                  if (p_selcb->next == &select_cb)
                  {
                      p_selcb->next = select_cb.next;
                      break;
                  }
  
          sys_sem_signal(selectsem);
  
          sys_sem_free(select_cb.sem);
          if (i == 0)             /* Timeout */
          {
              if (readset)
                  FD_ZERO(readset);
              if (writeset)
                  FD_ZERO(writeset);
              if (exceptset)
                  FD_ZERO(exceptset);
  
  	    LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_select: timeout expired\n"));
  	    set_errno(0);
  
              return 0;
          }
  
          if (readset)
              lreadset = *readset;
          else
              FD_ZERO(&lreadset);
          if (writeset)
              lwriteset = *writeset;
          else
              FD_ZERO(&lwriteset);
          if (exceptset)
              lexceptset = *exceptset;
          else
              FD_ZERO(&lexceptset);
  
          /* See what's set */
          nready = lwip_selscan(maxfdp1, &lreadset, &lwriteset, &lexceptset);
      }
      else
          sys_sem_signal(selectsem);
  
      if (readset)
          *readset = lreadset;
      if (writeset)
          *writeset = lwriteset;
      if (exceptset)
          *exceptset = lexceptset;
  
      LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_select: nready=%d\n", nready));
      set_errno(0);
  
      return nready;
  }
  
  
  static void
  event_callback(struct netconn *conn, enum netconn_evt evt, u16_t len)
  {
      int s;
      struct lwip_socket *sock;
      struct lwip_select_cb *scb;
  
      /* Get socket */
      if (conn)
      {
          s = conn->socket;
          if (s < 0)
          {
              /* Data comes in right away after an accept, even though
               * the server task might not have created a new socket yet.
               * Just count down (or up) if that's the case and we
               * will use the data later. Note that only receive events
               * can happen before the new socket is set up. */
              if (evt == NETCONN_EVT_RCVPLUS)
                  conn->socket--;
              return;
          }
  
          sock = get_socket(s);
          if (!sock)
              return;
      }
      else
          return;
  
      if (!selectsem)
          selectsem = sys_sem_new(1);
  
      sys_sem_wait(selectsem);
      /* Set event as required */
      switch (evt)
      {
        case NETCONN_EVT_RCVPLUS:
          sock->rcvevent++;
          break;
        case NETCONN_EVT_RCVMINUS:
          sock->rcvevent--;
          break;
        case NETCONN_EVT_SENDPLUS:
          sock->sendevent = 1;
          break;
        case NETCONN_EVT_SENDMINUS:
          sock->sendevent = 0;
          break;
      }
      sys_sem_signal(selectsem);
  
      /* Now decide if anyone is waiting for this socket */
      /* NOTE: This code is written this way to protect the select link list
         but to avoid a deadlock situation by releasing socksem before
         signalling for the select. This means we need to go through the list
         multiple times ONLY IF a select was actually waiting. We go through
         the list the number of waiting select calls + 1. This list is
         expected to be small. */
      while (1)
      {
          sys_sem_wait(selectsem);
          for (scb = select_cb_list; scb; scb = scb->next)
          {
              if (scb->sem_signalled == 0)
              {
                  /* Test this select call for our socket */
                  if (scb->readset && FD_ISSET(s, scb->readset))
                      if (sock->rcvevent)
                          break;
                  if (scb->writeset && FD_ISSET(s, scb->writeset))
                      if (sock->sendevent)
                          break;
              }
          }
          if (scb)
          {
              scb->sem_signalled = 1;
              sys_sem_signal(selectsem);
              sys_sem_signal(scb->sem);
          } else {
              sys_sem_signal(selectsem);
              break;
          }
      }
  
  }
  
  
  
  
  int lwip_shutdown(int s, int how)
  {
    LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_shutdown(%d, how=%d)\n", s, how));
    return lwip_close(s); /* XXX temporary hack until proper implementation */
  }
  
  int lwip_getpeername (int s, struct sockaddr *name, socklen_t *namelen)
  {
    struct lwip_socket *sock;
    struct sockaddr_in sin;
    struct ip_addr naddr;
  
    sock = get_socket(s);
    if (!sock) {
      set_errno(EBADF);
      return -1;
    }
  
    memset(&sin, 0, sizeof(sin));
    sin.sin_len = sizeof(sin);
    sin.sin_family = AF_INET;
  
    /* get the IP address and port of the remote host */
    netconn_peer(sock->conn, &naddr, &sin.sin_port);
  
    LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_getpeername(%d, addr=", s));
    ip_addr_debug_print(SOCKETS_DEBUG, &naddr);
    LWIP_DEBUGF(SOCKETS_DEBUG, (" port=%d)\n", sin.sin_port));
  
    sin.sin_port = htons(sin.sin_port);
    sin.sin_addr.s_addr = naddr.addr;
  
    if (*namelen > sizeof(sin))
        *namelen = sizeof(sin);
  
    memcpy(name, &sin, *namelen);
    sock_set_errno(sock, 0);
    return 0;
  }
  
  int lwip_getsockname (int s, struct sockaddr *name, socklen_t *namelen)
  {
    struct lwip_socket *sock;
    struct sockaddr_in sin;
    struct ip_addr *naddr;
  
    sock = get_socket(s);
    if (!sock) {
      set_errno(EBADF);
      return -1;
    }
  
    memset(&sin, 0, sizeof(sin));
    sin.sin_len = sizeof(sin);
    sin.sin_family = AF_INET;
  
    /* get the IP address and port of the remote host */
    netconn_addr(sock->conn, &naddr, &sin.sin_port);
  
    LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_getsockname(%d, addr=", s));
    ip_addr_debug_print(SOCKETS_DEBUG, naddr);
    LWIP_DEBUGF(SOCKETS_DEBUG, (" port=%d)\n", sin.sin_port));
  
    sin.sin_port = htons(sin.sin_port);
    sin.sin_addr.s_addr = naddr->addr;
  
    if (*namelen > sizeof(sin))
        *namelen = sizeof(sin);
  
    memcpy(name, &sin, *namelen);
    sock_set_errno(sock, 0);
    return 0;
  }
  
  int lwip_getsockopt (int s, int level, int optname, void *optval, socklen_t *optlen)
  {
    int err = 0;
    struct lwip_socket *sock = get_socket(s);
  
    if(!sock) {
     	set_errno(EBADF);
      return -1;
    }
  
    if( NULL == optval || NULL == optlen ) {
      sock_set_errno( sock, EFAULT );
      return -1;
    }
  
    /* Do length and type checks for the various options first, to keep it readable. */
    switch( level ) {
     
  /* Level: SOL_SOCKET */
    case SOL_SOCKET:
        switch(optname) {
           
        case SO_ACCEPTCONN:
        case SO_BROADCAST:
        /* UNIMPL case SO_DEBUG: */
        /* UNIMPL case SO_DONTROUTE: */
        case SO_ERROR:
        case SO_KEEPALIVE:
        /* UNIMPL case SO_OOBINLINE: */
        /* UNIMPL case SO_RCVBUF: */
        /* UNIMPL case SO_SNDBUF: */
        /* UNIMPL case SO_RCVLOWAT: */
        /* UNIMPL case SO_SNDLOWAT: */
  #if SO_REUSE
        case SO_REUSEADDR:
        case SO_REUSEPORT:
  #endif /* SO_REUSE */
        case SO_TYPE:
        /* UNIMPL case SO_USELOOPBACK: */
          if( *optlen < sizeof(int) ) {
            err = EINVAL;
          }
            break;
  
        default:
          LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_getsockopt(%d, SOL_SOCKET, UNIMPL: optname=0x%x, ..)\n", s, optname));
          err = ENOPROTOOPT;
        }  /* switch */
        break;
                       
  /* Level: IPPROTO_IP */
    case IPPROTO_IP:
        switch(optname) {
        /* UNIMPL case IP_HDRINCL: */
        /* UNIMPL case IP_RCVDSTADDR: */
        /* UNIMPL case IP_RCVIF: */
        case IP_TTL:
        case IP_TOS:
          if( *optlen < sizeof(int) ) {
            err = EINVAL;
          }
          break;
  
        default:
          LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_getsockopt(%d, IPPROTO_IP, UNIMPL: optname=0x%x, ..)\n", s, optname));
          err = ENOPROTOOPT;
        }  /* switch */
        break;
           
  /* Level: IPPROTO_TCP */
    case IPPROTO_TCP:
        if( *optlen < sizeof(int) ) {
          err = EINVAL;
          break;
      }
        
        /* If this is no TCP socket, ignore any options. */
        if ( sock->conn->type != NETCONN_TCP ) return 0;
  
        switch( optname ) {
        case TCP_NODELAY:
        case TCP_KEEPALIVE:
          break;
           
        default:
          LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_getsockopt(%d, IPPROTO_TCP, UNIMPL: optname=0x%x, ..)\n", s, optname));
          err = ENOPROTOOPT;
        }  /* switch */
        break;
  
  /* UNDEFINED LEVEL */
    default:
        LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_getsockopt(%d, level=0x%x, UNIMPL: optname=0x%x, ..)\n", s, level, optname));
        err = ENOPROTOOPT;
    }  /* switch */
  
     
    if( 0 != err ) {
      sock_set_errno(sock, err);
      return -1;
    }
     
  
  
    /* Now do the actual option processing */
  
    switch(level) {
     
  /* Level: SOL_SOCKET */
    case SOL_SOCKET:
      switch( optname ) {
  
      /* The option flags */
      case SO_ACCEPTCONN:
      case SO_BROADCAST:
      /* UNIMPL case SO_DEBUG: */
      /* UNIMPL case SO_DONTROUTE: */
      case SO_KEEPALIVE:
      /* UNIMPL case SO_OOBINCLUDE: */
  #if SO_REUSE
      case SO_REUSEADDR:
      case SO_REUSEPORT:
  #endif /* SO_REUSE */
      /*case SO_USELOOPBACK: UNIMPL */
        *(int*)optval = sock->conn->pcb.tcp->so_options & optname;
        LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_getsockopt(%d, SOL_SOCKET, optname=0x%x, ..) = %s\n", s, optname, (*(int*)optval?"on":"off")));
        break;
  
      case SO_TYPE:
        switch (sock->conn->type) {
        case NETCONN_RAW:
          *(int*)optval = SOCK_RAW;
          break;
        case NETCONN_TCP:
          *(int*)optval = SOCK_STREAM;
          break;
        case NETCONN_UDP:
        case NETCONN_UDPLITE:
        case NETCONN_UDPNOCHKSUM:
          *(int*)optval = SOCK_DGRAM;
          break;
        default: /* unrecognized socket type */
          *(int*)optval = sock->conn->type;
          LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_getsockopt(%d, SOL_SOCKET, SO_TYPE): unrecognized socket type %d\n", s, *(int *)optval));
        }  /* switch */
        LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_getsockopt(%d, SOL_SOCKET, SO_TYPE) = %d\n", s, *(int *)optval));
        break;
  
      case SO_ERROR:
        *(int *)optval = sock->err;
        sock->err = 0;
        LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_getsockopt(%d, SOL_SOCKET, SO_ERROR) = %d\n", s, *(int *)optval));
        break;
      }  /* switch */
      break;
  
  /* Level: IPPROTO_IP */
    case IPPROTO_IP:
      switch( optname ) {
      case IP_TTL:
        *(int*)optval = sock->conn->pcb.tcp->ttl;
        LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_getsockopt(%d, IPPROTO_IP, IP_TTL) = %d\n", s, *(int *)optval));
        break;
      case IP_TOS:
        *(int*)optval = sock->conn->pcb.tcp->tos;
        LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_getsockopt(%d, IPPROTO_IP, IP_TOS) = %d\n", s, *(int *)optval));
        break;
      }  /* switch */
      break;
  
  /* Level: IPPROTO_TCP */
    case IPPROTO_TCP:
      switch( optname ) {
      case TCP_NODELAY:
        *(int*)optval = (sock->conn->pcb.tcp->flags & TF_NODELAY);
        LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_getsockopt(%d, IPPROTO_TCP, TCP_NODELAY) = %s\n", s, (*(int*)optval)?"on":"off") );
        break;
      case TCP_KEEPALIVE:
        *(int*)optval = (int)sock->conn->pcb.tcp->keepalive;
        LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_getsockopt(%d, IPPROTO_IP, TCP_KEEPALIVE) = %d\n", s, *(int *)optval));
        break;
      }  /* switch */
      break;
    }
  
  
    sock_set_errno(sock, err);
    return err ? -1 : 0;
  }
  
  int lwip_setsockopt (int s, int level, int optname, const void *optval, socklen_t optlen)
  {
    struct lwip_socket *sock = get_socket(s);
    int err = 0;
  
    if(!sock) {
     	set_errno(EBADF);
      return -1;
    }
  
    if( NULL == optval ) {
      sock_set_errno( sock, EFAULT );
      return -1;
    }
  
  
    /* Do length and type checks for the various options first, to keep it readable. */
    switch( level ) {
  
  /* Level: SOL_SOCKET */
    case SOL_SOCKET:
      switch(optname) {
  
      case SO_BROADCAST:
      /* UNIMPL case SO_DEBUG: */
      /* UNIMPL case SO_DONTROUTE: */
      case SO_KEEPALIVE:
      /* UNIMPL case SO_OOBINLINE: */
      /* UNIMPL case SO_RCVBUF: */
      /* UNIMPL case SO_SNDBUF: */
      /* UNIMPL case SO_RCVLOWAT: */
      /* UNIMPL case SO_SNDLOWAT: */
  #if SO_REUSE
      case SO_REUSEADDR:
      case SO_REUSEPORT:
  #endif /* SO_REUSE */
      /* UNIMPL case SO_USELOOPBACK: */
        if( optlen < sizeof(int) ) {
          err = EINVAL;
        }
        break;
      default:
        LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_setsockopt(%d, SOL_SOCKET, UNIMPL: optname=0x%x, ..)\n", s, optname));
        err = ENOPROTOOPT;
      }  /* switch */
      break;
  
  /* Level: IPPROTO_IP */
    case IPPROTO_IP:
      switch(optname) {
      /* UNIMPL case IP_HDRINCL: */
      /* UNIMPL case IP_RCVDSTADDR: */
      /* UNIMPL case IP_RCVIF: */
      case IP_TTL:
      case IP_TOS:
        if( optlen < sizeof(int) ) {
          err = EINVAL;
        }
          break;
        default:
        LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_setsockopt(%d, IPPROTO_IP, UNIMPL: optname=0x%x, ..)\n", s, optname));
        err = ENOPROTOOPT;
      }  /* switch */
      break;
  
  /* Level: IPPROTO_TCP */
    case IPPROTO_TCP:
      if( optlen < sizeof(int) ) {
        err = EINVAL;
          break;
      }
  
      /* If this is no TCP socket, ignore any options. */
      if ( sock->conn->type != NETCONN_TCP ) return 0;
  
      switch( optname ) {
      case TCP_NODELAY:
      case TCP_KEEPALIVE:
        break;
  
      default:
        LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_setsockopt(%d, IPPROTO_TCP, UNIMPL: optname=0x%x, ..)\n", s, optname));
        err = ENOPROTOOPT;
      }  /* switch */
      break;
  
  /* UNDEFINED LEVEL */      
    default:
      LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_setsockopt(%d, level=0x%x, UNIMPL: optname=0x%x, ..)\n", s, level, optname));
      err = ENOPROTOOPT;
    }  /* switch */
  
  
    if( 0 != err ) {
      sock_set_errno(sock, err);
      return -1;
    }
  
  
  
    /* Now do the actual option processing */
  
    switch(level) {
  
  /* Level: SOL_SOCKET */
    case SOL_SOCKET:
      switch(optname) {
  
      /* The option flags */
      case SO_BROADCAST:
      /* UNIMPL case SO_DEBUG: */
      /* UNIMPL case SO_DONTROUTE: */
      case SO_KEEPALIVE:
      /* UNIMPL case SO_OOBINCLUDE: */
  #if SO_REUSE
      case SO_REUSEADDR:
      case SO_REUSEPORT:
  #endif /* SO_REUSE */
      /* UNIMPL case SO_USELOOPBACK: */
        if ( *(int*)optval ) {
          sock->conn->pcb.tcp->so_options |= optname;
        } else {
          sock->conn->pcb.tcp->so_options &= ~optname;
        }
        LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_setsockopt(%d, SOL_SOCKET, optname=0x%x, ..) -> %s\n", s, optname, (*(int*)optval?"on":"off")));
        break;
      }  /* switch */
      break;
  
  /* Level: IPPROTO_IP */
    case IPPROTO_IP:
      switch( optname ) {
      case IP_TTL:
        sock->conn->pcb.tcp->ttl = (u8_t)(*(int*)optval);
        LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_setsockopt(%d, IPPROTO_IP, IP_TTL, ..) -> %u\n", s, sock->conn->pcb.tcp->ttl));
        break;
      case IP_TOS:
        sock->conn->pcb.tcp->tos = (u8_t)(*(int*)optval);
        LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_setsockopt(%d, IPPROTO_IP, IP_TOS, ..)-> %u\n", s, sock->conn->pcb.tcp->tos));
        break;
      }  /* switch */
      break;
  
  /* Level: IPPROTO_TCP */
    case IPPROTO_TCP:
      switch( optname ) {
      case TCP_NODELAY:
        if ( *(int*)optval ) {
          sock->conn->pcb.tcp->flags |= TF_NODELAY;
        } else {
          sock->conn->pcb.tcp->flags &= ~TF_NODELAY;
        }
        LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_setsockopt(%d, IPPROTO_TCP, TCP_NODELAY) -> %s\n", s, (*(int *)optval)?"on":"off") );
        break;
      case TCP_KEEPALIVE:
        sock->conn->pcb.tcp->keepalive = (u32_t)(*(int*)optval);
        LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_setsockopt(%d, IPPROTO_TCP, TCP_KEEPALIVE) -> %lu\n", s, sock->conn->pcb.tcp->keepalive));
        break;
      }  /* switch */
      break;
    }  /* switch */
  
    sock_set_errno(sock, err);
    return err ? -1 : 0;
  }
  
  int lwip_ioctl(int s, long cmd, void *argp)
  {
    struct lwip_socket *sock = get_socket(s);
  
    if(!sock) {
     	set_errno(EBADF);
      return -1;
    }
  
    switch (cmd) {
    case FIONREAD:
      if (!argp) {
        sock_set_errno(sock, EINVAL);
        return -1;
      }
  
      *((u16_t*)argp) = sock->conn->recv_avail;
  
      LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_ioctl(%d, FIONREAD, %p) = %u\n", s, argp, *((u16_t*)argp)));
      sock_set_errno(sock, 0);
      return 0;
  
    case FIONBIO:
      if (argp && *(u32_t*)argp)
        sock->flags |= O_NONBLOCK;
      else
        sock->flags &= ~O_NONBLOCK;
      LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_ioctl(%d, FIONBIO, %d)\n", s, !!(sock->flags & O_NONBLOCK)));
      sock_set_errno(sock, 0);
      return 0;
  
    default:
      LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_ioctl(%d, UNIMPL: 0x%lx, %p)\n", s, cmd, argp));
      sock_set_errno(sock, ENOSYS); /* not yet implemented */
      return -1;
    }
  }
  
  