Fix accept() logic. it was not monitoring for losses in connections.

git-svn-id: https://nuttx.svn.sourceforge.net/svnroot/nuttx/trunk@4412 7fd9a85b-ad96-42d3-883c-3090e2eb8679

nuttx/ChangeLog

@@ -2477,3 +2477,8 @@
 	* arch/arm/src/stm32_sdio.c:  STM32 F4 SDIO DMA is now supported
 	* configs/stm3240g-eval/nsh/defconfig: This configuration now supports SDIO
 	  with DMA (see configs/stm3240g-eval/README.txt for some issues).
+	* net/accept.c, connect.c,and net_monitor.c:  Correct an error in the accept
+	  logic.  After a new connection is made via accept(), monitoring for losses
+	  of TCP connection must be set up (just as with connect()).  The new file
+	  net_monitor.c holds the common TCP connection monitoring logic used by both
+	  the accecpt() and connect() logic.  Contributed by Max Nekludov.

nuttx/net/Makefile

@@ -47,7 +47,7 @@ SOCK_CSRCS = bind.c connect.c getsockname.c recv.c recvfrom.c socket.c \
 # TCP/IP support
 
 ifeq ($(CONFIG_NET_TCP),y)
-SOCK_CSRCS += send.c listen.c accept.c 
+SOCK_CSRCS += send.c listen.c accept.c net_monitor.c
 endif
 
 # Socket options

nuttx/net/accept.c

@@ -305,8 +305,8 @@ int accept(int sockfd, struct sockaddr *addr, socklen_t *addrlen)
       goto errout;
     }
 
-  /* Verify that a valid memory block has been provided to receive
+  /* Verify that a valid memory block has been provided to receive the
-   * the address
+   * address
    */
 
   if (addr)
@@ -322,8 +322,8 @@ int accept(int sockfd, struct sockaddr *addr, socklen_t *addrlen)
         }
     }
 
-  /* Allocate a socket descriptor for the new connection now
+  /* Allocate a socket descriptor for the new connection now (so that it
-   * (so that it cannot fail later)
+   * cannot fail later)
    */
 
   newfd = sockfd_allocate(0);
@@ -340,8 +340,8 @@ int accept(int sockfd, struct sockaddr *addr, socklen_t *addrlen)
       goto errout_with_socket;
     }
 
-  /* Check the backlog to see if there is a connection already pending
+  /* Check the backlog to see if there is a connection already pending for
-   * for this listener.
+   * this listener.
    */
 
   save = uip_lock();
@@ -412,7 +412,7 @@ int accept(int sockfd, struct sockaddr *addr, socklen_t *addrlen)
       psock->s_flags = _SS_SETSTATE(psock->s_flags, _SF_IDLE);
 
       /* Check for a errors.  Errors are signaled by negative errno values
-       * for the send length
+       * for the send length.
        */
 
       if (state.acpt_result != 0)
@@ -431,7 +431,6 @@ int accept(int sockfd, struct sockaddr *addr, socklen_t *addrlen)
           goto errout_with_lock;
         }
     }
-  uip_unlock(save);
 
   /* Initialize the socket structure and mark the socket as connected.
    * (The reference count on the new connection structure was set in the
@@ -442,6 +441,11 @@ int accept(int sockfd, struct sockaddr *addr, socklen_t *addrlen)
   pnewsock->s_conn   = state.acpt_newconn;
   pnewsock->s_flags |= _SF_CONNECTED;
   pnewsock->s_flags &= ~_SF_CLOSED;
+
+  /* Begin monitoring for TCP connection events on the newly connected socket */
+
+  net_startmonitor(pnewsock);
+  uip_unlock(save);
   return newfd;
 
 errout_with_lock:

nuttx/net/connect.c

@@ -1,8 +1,8 @@
 /****************************************************************************
  * net/connect.c
  *
- *   Copyright (C) 2007-2011 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2007-2012 Gregory Nutt. All rights reserved.
- *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+ *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
@@ -72,7 +72,6 @@ struct tcp_connect_s
  ****************************************************************************/
 
 #ifdef CONFIG_NET_TCP
-static void connection_event(struct uip_conn *conn, uint16_t flags);
 static inline int tcp_setup_callbacks(FAR struct socket *psock,
                                       FAR struct tcp_connect_s *pstate);
 static inline void tcp_teardown_callbacks(struct tcp_connect_s *pstate, int status);
@@ -89,81 +88,7 @@ static inline int tcp_connect(FAR struct socket *psock, const struct sockaddr_in
  * Private Functions
  ****************************************************************************/
 /****************************************************************************
- * Function: connection_event
+ * Name: tcp_setup_callbacks
- *
- * Description:
- *   Some connection related event has occurred
- *
- * Parameters:
- *   dev      The sructure of the network driver that caused the interrupt
- *   conn     The connection structure associated with the socket
- *   flags    Set of events describing why the callback was invoked
- *
- * Returned Value:
- *   None
- *
- * Assumptions:
- *   Running at the interrupt level
- *
- ****************************************************************************/
-
-#ifdef CONFIG_NET_TCP
-static void connection_event(struct uip_conn *conn, uint16_t flags)
-{
-  FAR struct socket *psock = (FAR struct socket *)conn->connection_private;
-
-  if (psock)
-    {
-      nllvdbg("flags: %04x s_flags: %02x\n", flags, psock->s_flags);
-
-      /* These loss-of-connection events may be reported:
-       *
-       *   UIP_CLOSE: The remote host has closed the connection
-       *   UIP_ABORT: The remote host has aborted the connection
-       *   UIP_TIMEDOUT: Connection aborted due to too many retransmissions.
-       *
-       * And we need to set these two socket status bits appropriately:
-       *
-       *  _SF_CONNECTED==1 && _SF_CLOSED==0 - the socket is connected
-       *  _SF_CONNECTED==0 && _SF_CLOSED==1 - the socket was gracefully disconnected
-       *  _SF_CONNECTED==0 && _SF_CLOSED==0 - the socket was rudely disconnected
-       */
-
-      if ((flags & UIP_CLOSE) != 0)
-        {
-          /* The peer gracefully closed the connection.  Marking the
-           * connection as disconnected will suppress some subsequent
-           * ENOTCONN errors from receive.  A graceful disconnection is
-           * not handle as an error but as an "end-of-file"
-           */
-
-          psock->s_flags &= ~_SF_CONNECTED;
-          psock->s_flags |= _SF_CLOSED;
-        }
-      else if ((flags & (UIP_ABORT|UIP_TIMEDOUT)) != 0)
-        {
-          /* The loss of connection was less than graceful.  This will (eventually)
-           * be reported as an ENOTCONN error.
-           */
-
-          psock->s_flags &= ~(_SF_CONNECTED |_SF_CLOSED);
-        }
-
-      /* UIP_CONNECTED: The socket is successfully connected */
-
-      else if ((flags & UIP_CONNECTED) != 0)
-        {
-          /* Indicate that the socket is now connected */
-
-          psock->s_flags |= _SF_CONNECTED;
-          psock->s_flags &= ~_SF_CLOSED;
-        }
-    }
-}
-#endif /* CONFIG_NET_TCP */
-
-/****************************************************************************
- * Function: tcp_setup_callbacks
  ****************************************************************************/
 
 #ifdef CONFIG_NET_TCP
@@ -184,14 +109,15 @@ static inline int tcp_setup_callbacks(FAR struct socket *psock,
   pstate->tc_cb = uip_tcpcallbackalloc(conn);
   if (pstate->tc_cb)
     {
+      /* Set up the connection "interrupt" handler */
+
       pstate->tc_cb->flags   = UIP_NEWDATA|UIP_CLOSE|UIP_ABORT|UIP_TIMEDOUT|UIP_CONNECTED;
       pstate->tc_cb->priv    = (void*)pstate;
       pstate->tc_cb->event   = tcp_connect_interrupt;
 
-      /* Set up to receive callbacks on connection-related events */
+      /* Set up the connection event monitor */
 
-      conn->connection_private = (void*)psock;
+      net_startmonitor(psock);
-      conn->connection_event   = connection_event;
       ret = OK;
     }
   return ret;
@@ -199,34 +125,34 @@ static inline int tcp_setup_callbacks(FAR struct socket *psock,
 #endif /* CONFIG_NET_TCP */
 
 /****************************************************************************
- * Function: tcp_teardown_callbacks
+ * Name: tcp_teardown_callbacks
  ****************************************************************************/
 
 #ifdef CONFIG_NET_TCP
-static inline void tcp_teardown_callbacks(struct tcp_connect_s *pstate, int status)
+static inline void tcp_teardown_callbacks(struct tcp_connect_s *pstate,
+                                          int status)
 {
-  struct uip_conn *conn = pstate->tc_conn;
+  FAR struct uip_conn *conn = pstate->tc_conn;
 
   /* Make sure that no further interrupts are processed */
 
   uip_tcpcallbackfree(conn, pstate->tc_cb);
 
-  /* If we successfully connected, we will continue to monitor the connection state
+  /* If we successfully connected, we will continue to monitor the connection
-   * via callbacks.
+   * state via callbacks.
    */
 
   if (status < 0)
     {
-      /* Failed to connect */
+      /* Stop the connection event monitor */
 
-      conn->connection_private = NULL;
+      net_stopmonitor(conn);
-      conn->connection_event   = NULL;
     }
 }
 #endif /* CONFIG_NET_TCP */
 
 /****************************************************************************
- * Function: tcp_connect_interrupt
+ * Name: tcp_connect_interrupt
  *
  * Description:
  *   This function is called from the interrupt level to perform the actual
@@ -323,7 +249,7 @@ static uint16_t tcp_connect_interrupt(struct uip_driver_s *dev, void *pvconn,
 #endif /* CONFIG_NET_TCP */
 
 /****************************************************************************
- * Function: tcp_connect
+ * Name: tcp_connect
  *
  * Description:
  *   Perform a TCP connection
@@ -428,7 +354,7 @@ static inline int tcp_connect(FAR struct socket *psock, const struct sockaddr_in
  * Public Functions
  ****************************************************************************/
 /****************************************************************************
- * Function: connect
+ * Name: connect
  *
  * Description:
  *   connect() connects the socket referred to by the file descriptor sockfd

nuttx/net/net_internal.h

@@ -165,6 +165,13 @@ EXTERN void sock_release(FAR struct socket *psock);
 EXTERN void sockfd_release(int sockfd);
 EXTERN FAR struct socket *sockfd_socket(int sockfd);
 
+/* net_connect.c *************************************************************/
+
+#ifdef CONFIG_NET_TCP
+EXTERN int net_startmonitor(FAR struct socket *psock);
+EXTERN void net_stopmonitor(FAR struct uip_conn *conn);
+#endif
+
 /* net_close.c ***************************************************************/
 
 EXTERN int psock_close(FAR struct socket *psock);

nuttx/net/net_monitor.c

@@ -0,0 +1,186 @@
+/****************************************************************************
+ * net/net_monitor.c
+ *
+ *   Copyright (C) 2007-2012 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <gnutt@nuttx.org>
+ *
+ * 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 NuttX 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 COPYRIGHT HOLDERS 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
+ * COPYRIGHT OWNER 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.
+ *
+ ****************************************************************************/
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+#if defined(CONFIG_NET) && defined(CONFIG_NET_TCP)
+
+#include <stdint.h>
+#include <debug.h>
+
+#include "net_internal.h"
+#include "uip/uip_internal.h"
+
+/****************************************************************************
+ * Private Types
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Function Prototypes
+ ****************************************************************************/
+
+static void connection_event(struct uip_conn *conn, uint16_t flags);
+
+/****************************************************************************
+ * Private Functions
+ ****************************************************************************/
+/****************************************************************************
+ * Name: connection_event
+ *
+ * Description:
+ *   Some connection related event has occurred
+ *
+ * Parameters:
+ *   dev      The sructure of the network driver that caused the interrupt
+ *   conn     The connection structure associated with the socket
+ *   flags    Set of events describing why the callback was invoked
+ *
+ * Returned Value:
+ *   None
+ *
+ * Assumptions:
+ *   Running at the interrupt level
+ *
+ ****************************************************************************/
+
+static void connection_event(struct uip_conn *conn, uint16_t flags)
+{
+  FAR struct socket *psock = (FAR struct socket *)conn->connection_private;
+
+  if (psock)
+    {
+      nllvdbg("flags: %04x s_flags: %02x\n", flags, psock->s_flags);
+
+      /* These loss-of-connection events may be reported:
+       *
+       *   UIP_CLOSE: The remote host has closed the connection
+       *   UIP_ABORT: The remote host has aborted the connection
+       *   UIP_TIMEDOUT: Connection aborted due to too many retransmissions.
+       *
+       * And we need to set these two socket status bits appropriately:
+       *
+       *  _SF_CONNECTED==1 && _SF_CLOSED==0 - the socket is connected
+       *  _SF_CONNECTED==0 && _SF_CLOSED==1 - the socket was gracefully disconnected
+       *  _SF_CONNECTED==0 && _SF_CLOSED==0 - the socket was rudely disconnected
+       */
+
+      if ((flags & UIP_CLOSE) != 0)
+        {
+          /* The peer gracefully closed the connection.  Marking the
+           * connection as disconnected will suppress some subsequent
+           * ENOTCONN errors from receive.  A graceful disconnection is
+           * not handle as an error but as an "end-of-file"
+           */
+
+          psock->s_flags &= ~_SF_CONNECTED;
+          psock->s_flags |= _SF_CLOSED;
+        }
+      else if ((flags & (UIP_ABORT|UIP_TIMEDOUT)) != 0)
+        {
+          /* The loss of connection was less than graceful.  This will (eventually)
+           * be reported as an ENOTCONN error.
+           */
+
+          psock->s_flags &= ~(_SF_CONNECTED |_SF_CLOSED);
+        }
+
+      /* UIP_CONNECTED: The socket is successfully connected */
+
+      else if ((flags & UIP_CONNECTED) != 0)
+        {
+          /* Indicate that the socket is now connected */
+
+          psock->s_flags |= _SF_CONNECTED;
+          psock->s_flags &= ~_SF_CLOSED;
+        }
+    }
+}
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+/****************************************************************************
+ * Name: net_startmonitor
+ *
+ * Description:
+ *   Set up to receive TCP connection state changes for a given socket
+ *
+ * Input Parameters:
+ *   psock - The socket of interest
+ *
+ * Returned Value:
+ *   For now, this function always returns OK.
+ *
+ ****************************************************************************/
+
+int net_startmonitor(FAR struct socket *psock)
+{
+  FAR struct uip_conn *conn = psock->s_conn;
+
+  DEBUGASSERT(psock && conn);
+
+  /* Set up to receive callbacks on connection-related events */
+
+  conn->connection_private = (void*)psock;
+  conn->connection_event   = connection_event;
+  return OK;
+}
+
+/****************************************************************************
+ * Name: net_stopmonitor
+ *
+ * Description:
+ *   Stop monitoring TCP connection changes for a given socket
+ *
+ * Input Parameters:
+ *   conn - The TCP connection of interest
+ *
+ * Returned Value:
+ *   None
+ *
+ ****************************************************************************/
+
+void net_stopmonitor(FAR struct uip_conn *conn)
+{
+  DEBUGASSERT(conn);
+
+  conn->connection_private = NULL;
+  conn->connection_event   = NULL;
+}
+
+#endif /* CONFIG_NET && CONFIG_NET_TCP */