diff options
Diffstat (limited to 'nuttx/net/uip/uip-tcpbacklog.c')
| -rw-r--r-- | nuttx/net/uip/uip-tcpbacklog.c | 348 |
1 files changed, 348 insertions, 0 deletions
diff --git a/nuttx/net/uip/uip-tcpbacklog.c b/nuttx/net/uip/uip-tcpbacklog.c new file mode 100644 index 000000000..152d374ba --- /dev/null +++ b/nuttx/net/uip/uip-tcpbacklog.c @@ -0,0 +1,348 @@ +/**************************************************************************** + * net/uip/uip-tcpbacklog.c + * + * Copyright (C) 2008 Gregory Nutt. All rights reserved. + * Author: Gregory Nutt <spudmonkey@racsa.co.cr> + * + * 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 <net/uip/uipopt.h> +#if defined(CONFIG_NET) && defined(CONFIG_NET_TCP) && defined(CONFIG_NET_TCPBACKLOG) + +#include <sys/types.h> + +#include <stdlib.h> +#include <queue.h> +#include <debug.h> + +#include <net/uip/uip.h> +#include <net/uip/uip-tcp.h> + +#include "uip-internal.h" + +/**************************************************************************** + * Private Data + ****************************************************************************/ + +/**************************************************************************** + * Private Functions + ****************************************************************************/ + +/**************************************************************************** + * Public Functions + ****************************************************************************/ + +/**************************************************************************** + * Function: uip_backlogcreate + * + * Description: + * Called from the listen() logic to setup the backlog as specified in the + * the listen arguments *. + * + * Assumptions: + * Called from normal user code. Interrupts may be disabled. + * + ****************************************************************************/ + +int uip_backlogcreate(FAR struct uip_conn *conn, int nblg) +{ + FAR struct uip_backlog_s *bls = NULL; + FAR struct uip_blcontainer_s *blc; + irqstate_t flags; + int size; + int offset; + int i; + +#ifdef CONFIG_DEBUG + if (!conn) + { + return -EINVAL; + } +#endif + + /* Then allocate the backlog as requested */ + + if (nblg > 0) + { + /* Align the list of backlog structures to 32-bit boundaries. This + * may be excessive on 24-16-bit address machines; and insufficient + * on 64-bit address machines -- REVISIT + */ + + offset = (sizeof(struct uip_backlog_s) + 3) & ~3; + + /* Then determine the full size of the allocation include the + * uip_backlog_s, a pre-allocated array of struct uip_blcontainer_s + * and alignement padding + */ + + size = offset + nblg * sizeof(struct uip_blcontainer_s); + + /* Then allocate that much */ + + bls = (FAR struct uip_backlog_s *)zalloc(size); + if (!bls) + { + return -ENOMEM; + } + + /* Then add all of the pre-allocated containers to the the free list */ + + blc = (FAR struct uip_blcontainer_s*)(((FAR ubyte*)bls) + offset); + for (i = 0; i < nblg; i++) + { + dq_addfirst(&blc->bc_node, &bls->bl_free); + } + } + + /* Destroy any existing backlog (shouldn't be any) */ + + flags = irqsave(); + uip_backlogdestroy(conn); + + /* Now install the backlog tear-off in the connection. NOTE that bls may + * actually be NULL if nblg is <= 0; In that case, we are disabling backlog + * support. Since interrupts are disabled, destroying the old backlog and + * replace it with the new is an atomic operation + */ + + conn->backlog = bls; + irqrestore(flags); + return OK; +} + +/**************************************************************************** + * Function: uip_backlogdestroy + * + * Description: + * (1) Called from uip_tcpfree() whenever a connection is freed. + * (2) Called from uip_backlogcreate() to destroy any old backlog + * + * NOTE: This function may re-enter uip_tcpfree when a connection that + * is freed that has pending connections. + * + * Assumptions: + * The caller has disabled interrupts so that there can be no conflict + * with ongoing, interrupt driven activity + * + ****************************************************************************/ + +int uip_backlogdestroy(FAR struct uip_conn *conn) +{ + FAR struct uip_backlog_s *blg; + FAR struct uip_blcontainer_s *blc; + FAR struct uip_conn *blconn; + +#ifdef CONFIG_DEBUG + if (!conn) + { + return -EINVAL; + } +#endif + + /* Make sure that the connection has a backlog to be destroyed */ + + if (conn->backlog) + { + /* Remove the backlog structure reference from the connection */ + + blg = conn->backlog; + conn->backlog = NULL; + + /* Handle any pending connections in the backlog */ + + while ((blc = (FAR struct uip_blcontainer_s*)dq_remfirst(&blg->bl_pending)) != NULL) + { + blconn = blc->bc_conn; + if (blconn) + { + /* REVISIT -- such connections really need to be gracefully closed */ + + blconn->blparent = NULL; + blconn->backlog = NULL; + uip_tcpfree(blconn); + } + } + + /* Then free the entire backlog structure */ + + free(blg); + } + + return OK; +} + +/**************************************************************************** + * Function: uip_backlogadd + * + * Description: + * Called uip_listen when a new connection is made with a listener socket + * but when there is not accept() in place to receive the connection. This + * function adds the new connection to the backlog. + * + * Assumptions: + * Called from the interrupt level with interrupts disabled + * + ****************************************************************************/ + +int uip_backlogadd(FAR struct uip_conn *conn, FAR struct uip_conn *blconn) +{ + FAR struct uip_backlog_s *bls; + FAR struct uip_blcontainer_s *blc; + int ret = -EINVAL; + +#ifdef CONFIG_DEBUG + if (!conn) + { + return -EINVAL; + } +#endif + + bls = conn->backlog; + if (conn->backlog && blconn) + { + /* Allocate a container for the connection from the free list */ + + blc = (FAR struct uip_blcontainer_s *)dq_remfirst(&bls->bl_free); + if (!blc) + { + ret = -ENOMEM; + } + else + { + /* Save the connection reference in the container and put the + * container at the end of the pending connection list (FIFO). + */ + + blc->bc_conn = blconn; + dq_addlast(&blc->bc_node, &bls->bl_pending); + ret = OK; + } + } + return ret; +} + +/**************************************************************************** + * Function: uip_backlogremove + * + * Description: + * Called from accept(). Before waiting for a new connection, accept will + * call this API to see if there are pending connections in the backlog. + * + * Assumptions: + * Called from normal user code, but with interrupts disabled, + * + ****************************************************************************/ + +struct uip_conn *uip_backlogremove(FAR struct uip_conn *conn) +{ + FAR struct uip_backlog_s *bls; + FAR struct uip_blcontainer_s *blc; + FAR struct uip_conn *blconn = NULL; + +#ifdef CONFIG_DEBUG + if (!conn) + { + return NULL; + } +#endif + bls = conn->backlog; + if (bls && blconn) + { + /* Remove the a container at the head of the pending connection list + * (FIFO) + */ + + blc = (FAR struct uip_blcontainer_s *)dq_remfirst(&bls->bl_pending); + if (blc) + { + /* Extract the connection reference from the container and put + * container in the free list + */ + + blconn = blc->bc_conn; + blc->bc_conn = NULL; + dq_addlast(&blc->bc_node, &bls->bl_free); + } + } + return blconn; +} + +/**************************************************************************** + * Function: uip_backlogdelete + * + * Description: + * Called from uip_tcpfree() when a connection is freed that this also + * retained in the pending connectino list of a listener. We simply need + * to remove the defunct connecton from the list. + * + * Assumptions: + * Called from the interrupt level with interrupts disabled + * + ****************************************************************************/ + +int uip_backlogdelete(FAR struct uip_conn *conn, FAR struct uip_conn *blconn) +{ + FAR struct uip_backlog_s *bls; + FAR struct uip_blcontainer_s *blc; + +#ifdef CONFIG_DEBUG + if (!conn) + { + return NULL; + } +#endif + bls = conn->backlog; + if (bls) + { + /* Find the container hold the connection */ + + for (blc = (FAR struct uip_blcontainer_s *)dq_peek(&bls->bl_pending); + blc; + blc = (FAR struct uip_blcontainer_s *)dq_next(&blc->bc_node)) + { + if (blc->bc_conn == blconn) + { + /* Remove the a container from the list of pending connections */ + + dq_rem(&blc->bc_node, &bls->bl_pending); + return OK; + } + } + return -EINVAL; + } + return OK; +} + +#endif /* CONFIG_NET && CONFIG_NET_TCP && CONFIG_NET_TCPBACKLOG */ |