uhd: tweaks to calibration utilities

1 files changed, 0 insertions, 981 deletions

diff --git a/firmware/zpu/lwip/lwip-1.3.1/src/core/#tcp_out.c# b/firmware/zpu/lwip/lwip-1.3.1/src/core/#tcp_out.c#
deleted file mode 100644
index ca72d9dcc..000000000
--- a/firmware/zpu/lwip/lwip-1.3.1/src/core/#tcp_out.c#
+++ /dev/null
@@ -1,981 +0,0 @@
-/**
- * @file
- * Transmission Control Protocol, outgoing traffic
- *
- * The output functions of TCP.
- *
- */
-
-/*
- * 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>
- *
- */
-
-#include "lwip/opt.h"
-
-#if LWIP_TCP /* don't build if not configured for use in lwipopts.h */
-
-#include "lwip/tcp.h"
-#include "lwip/def.h"
-#include "lwip/mem.h"
-#include "lwip/memp.h"
-#include "lwip/sys.h"
-#include "lwip/ip_addr.h"
-#include "lwip/netif.h"
-#include "lwip/inet.h"
-#include "lwip/inet_chksum.h"
-#include "lwip/stats.h"
-#include "lwip/snmp.h"
-
-#include <string.h>
-
-/* Forward declarations.*/
-static void tcp_output_segment(struct tcp_seg *seg, struct tcp_pcb *pcb);
-
-static struct tcp_hdr *
-tcp_output_set_header(struct tcp_pcb *pcb, struct pbuf *p, int optlen,
-                      u32_t seqno_be /* already in network byte order */)
-{
-  struct tcp_hdr *tcphdr = p->payload;
-  tcphdr->src = htons(pcb->local_port);
-  tcphdr->dest = htons(pcb->remote_port);
-  tcphdr->seqno = seqno_be;
-  tcphdr->ackno = htonl(pcb->rcv_nxt);
-  TCPH_FLAGS_SET(tcphdr, TCP_ACK);
-  tcphdr->wnd = htons(pcb->rcv_ann_wnd);
-  tcphdr->urgp = 0;
-  TCPH_HDRLEN_SET(tcphdr, (5 + optlen / 4));
-  tcphdr->chksum = 0;
-
-  /* If we're sending a packet, update the announced right window edge */
-  pcb->rcv_ann_right_edge = pcb->rcv_nxt + pcb->rcv_ann_wnd;
-
-  return tcphdr;
-}
-
-/**
- * Called by tcp_close() to send a segment including flags but not data.
- *
- * @param pcb the tcp_pcb over which to send a segment
- * @param flags the flags to set in the segment header
- * @return ERR_OK if sent, another err_t otherwise
- */
-err_t
-tcp_send_ctrl(struct tcp_pcb *pcb, u8_t flags)
-{
-  /* no data, no length, flags, copy=1, no optdata */
-  return tcp_enqueue(pcb, NULL, 0, flags, TCP_WRITE_FLAG_COPY, 0);
-}
-
-/**
- * Write data for sending (but does not send it immediately).
- *
- * It waits in the expectation of more data being sent soon (as
- * it can send them more efficiently by combining them together).
- * To prompt the system to send data now, call tcp_output() after
- * calling tcp_write().
- * 
- * @param pcb Protocol control block of the TCP connection to enqueue data for.
- * @param data pointer to the data to send
- * @param len length (in bytes) of the data to send
- * @param apiflags combination of following flags :
- * - TCP_WRITE_FLAG_COPY (0x01) data will be copied into memory belonging to the stack
- * - TCP_WRITE_FLAG_MORE (0x02) for TCP connection, PSH flag will be set on last segment sent,
- * @return ERR_OK if enqueued, another err_t on error
- * 
- * @see tcp_write()
- */
-err_t
-tcp_write(struct tcp_pcb *pcb, const void *data, u16_t len, u8_t apiflags)
-{
-  LWIP_DEBUGF(TCP_OUTPUT_DEBUG, ("tcp_write(pcb=%p, data=%p, len=%"U16_F", apiflags=%"U16_F")\n", (void *)pcb,
-    data, len, (u16_t)apiflags));
-  /* connection is in valid state for data transmission? */
-  if (pcb->state == ESTABLISHED ||
-     pcb->state == CLOSE_WAIT ||
-     pcb->state == SYN_SENT ||
-     pcb->state == SYN_RCVD) {
-    if (len > 0) {
-#if LWIP_TCP_TIMESTAMPS
-      return tcp_enqueue(pcb, (void *)data, len, 0, apiflags, 
-                         pcb->flags & TF_TIMESTAMP ? TF_SEG_OPTS_TS : 0);
-#else
-      return tcp_enqueue(pcb, (void *)data, len, 0, apiflags, 0);
-#endif
-    }
-    return ERR_OK;
-  } else {
-    LWIP_DEBUGF(TCP_OUTPUT_DEBUG | LWIP_DBG_STATE | 3, ("tcp_write() called in invalid state\n"));
-    return ERR_CONN;
-  }
-}
-
-/**
- * Enqueue data and/or TCP options for transmission
- *
- * Called by tcp_connect(), tcp_listen_input(), tcp_send_ctrl() and tcp_write().
- *
- * @param pcb Protocol control block for the TCP connection to enqueue data for.
- * @param arg Pointer to the data to be enqueued for sending.
- * @param len Data length in bytes
- * @param flags tcp header flags to set in the outgoing segment
- * @param apiflags combination of following flags :
- * - TCP_WRITE_FLAG_COPY (0x01) data will be copied into memory belonging to the stack
- * - TCP_WRITE_FLAG_MORE (0x02) for TCP connection, PSH flag will be set on last segment sent,
- * @param optflags options to include in segment later on (see definition of struct tcp_seg)
- */
-err_t
-tcp_enqueue(struct tcp_pcb *pcb, void *arg, u16_t len,
-            u8_t flags, u8_t apiflags, u8_t optflags)
-{
-  struct pbuf *p;
-  struct tcp_seg *seg, *useg, *queue;
-  u32_t seqno;
-  u16_t left, seglen;
-  void *ptr;
-  u16_t queuelen;
-  u8_t optlen;
-
-  LWIP_DEBUGF(TCP_OUTPUT_DEBUG, 
-              ("tcp_enqueue(pcb=%p, arg=%p, len=%"U16_F", flags=%"X16_F", apiflags=%"U16_F")\n",
-               (void *)pcb, arg, len, (u16_t)flags, (u16_t)apiflags));
-  LWIP_ERROR("tcp_enqueue: packet needs payload, options, or SYN/FIN (programmer violates API)",
-             ((len != 0) || (optflags != 0) || ((flags & (TCP_SYN | TCP_FIN)) != 0)),
-             return ERR_ARG;);
-  LWIP_ERROR("tcp_enqueue: len != 0 || arg == NULL (programmer violates API)", 
-             ((len != 0) || (arg == NULL)), return ERR_ARG;);
-
-  /* fail on too much data */
-  if (len > pcb->snd_buf) {
-    LWIP_DEBUGF(TCP_OUTPUT_DEBUG | 3, ("tcp_enqueue: too much data (len=%"U16_F" > snd_buf=%"U16_F")\n", len, pcb->snd_buf));
-    pcb->flags |= TF_NAGLEMEMERR;
-    return ERR_MEM;
-  }
-  left = len;
-  ptr = arg;
-
-  optlen = LWIP_TCP_OPT_LENGTH(optflags);
-
-  /* seqno will be the sequence number of the first segment enqueued
-   * by the call to this function. */
-  seqno = pcb->snd_lbb;
-
-  LWIP_DEBUGF(TCP_QLEN_DEBUG, ("tcp_enqueue: queuelen: %"U16_F"\n", (u16_t)pcb->snd_queuelen));
-
-  /* If total number of pbufs on the unsent/unacked queues exceeds the
-   * configured maximum, return an error */
-  queuelen = pcb->snd_queuelen;
-  /* check for configured max queuelen and possible overflow */
-  if ((queuelen >= TCP_SND_QUEUELEN) || (queuelen > TCP_SNDQUEUELEN_OVERFLOW)) {
-    LWIP_DEBUGF(TCP_OUTPUT_DEBUG | 3, ("tcp_enqueue: too long queue %"U16_F" (max %"U16_F")\n", queuelen, TCP_SND_QUEUELEN));
-    TCP_STATS_INC(tcp.memerr);
-    pcb->flags |= TF_NAGLEMEMERR;
-    return ERR_MEM;
-  }
-  if (queuelen != 0) {
-    LWIP_ASSERT("tcp_enqueue: pbufs on queue => at least one queue non-empty",
-      pcb->unacked != NULL || pcb->unsent != NULL);
-  } else {
-    LWIP_ASSERT("tcp_enqueue: no pbufs on queue => both queues empty",
-      pcb->unacked == NULL && pcb->unsent == NULL);
-  }
-
-  /* First, break up the data into segments and tuck them together in
-   * the local "queue" variable. */
-  useg = queue = seg = NULL;
-  seglen = 0;
-  while (queue == NULL || left > 0) {
-    /* The segment length (including options) should be at most the MSS */
-    seglen = left > (pcb->mss - optlen) ? (pcb->mss - optlen) : left;
-
-    /* Allocate memory for tcp_seg, and fill in fields. */
-    seg = memp_malloc(MEMP_TCP_SEG);
-    if (seg == NULL) {
-      LWIP_DEBUGF(TCP_OUTPUT_DEBUG | 2, 
-                  ("tcp_enqueue: could not allocate memory for tcp_seg\n"));
-      goto memerr;
-    }
-    seg->next = NULL;
-    seg->p = NULL;
-
-    /* first segment of to-be-queued data? */
-    if (queue == NULL) {
-      queue = seg;
-    }
-    /* subsequent segments of to-be-queued data */
-    else {
-      /* Attach the segment to the end of the queued segments */
-      LWIP_ASSERT("useg != NULL", useg != NULL);
-      useg->next = seg;
-    }
-    /* remember last segment of to-be-queued data for next iteration */
-    useg = seg;
-
-    /* If copy is set, memory should be allocated
-     * and data copied into pbuf, otherwise data comes from
-     * ROM or other static memory, and need not be copied.  */
-    if (apiflags & TCP_WRITE_FLAG_COPY) {
-      if ((seg->p = pbuf_alloc(PBUF_TRANSPORT, seglen + optlen, PBUF_RAM)) == NULL) {
-        LWIP_DEBUGF(TCP_OUTPUT_DEBUG | 2, 
-                    ("tcp_enqueue : could not allocate memory for pbuf copy size %"U16_F"\n", seglen));
-        goto memerr;
-      }
-      LWIP_ASSERT("check that first pbuf can hold the complete seglen",
-                  (seg->p->len >= seglen + optlen));
-      queuelen += pbuf_clen(seg->p);
-      if (arg != NULL) {
-        MEMCPY((char *)seg->p->payload + optlen, ptr, seglen);
-      }
-      seg->dataptr = seg->p->payload;
-    }
-    /* do not copy data */
-    else {
-      /* First, allocate a pbuf for the headers. */
-      if ((seg->p = pbuf_alloc(PBUF_TRANSPORT, optlen, PBUF_RAM)) == NULL) {
-        LWIP_DEBUGF(TCP_OUTPUT_DEBUG | 2, 
-                    ("tcp_enqueue: could not allocate memory for header pbuf\n"));
-        goto memerr;
-      }
-      queuelen += pbuf_clen(seg->p);
-
-      /* Second, allocate a pbuf for holding the data.
-       * since the referenced data is available at least until it is sent out on the
-       * link (as it has to be ACKed by the remote party) we can safely use PBUF_ROM
-       * instead of PBUF_REF here.
-       */
-      if (left > 0) {
-        if ((p = pbuf_alloc(PBUF_RAW, seglen, PBUF_ROM)) == NULL) {
-          /* If allocation fails, we have to deallocate the header pbuf as well. */
-          pbuf_free(seg->p);
-          seg->p = NULL;
-          LWIP_DEBUGF(TCP_OUTPUT_DEBUG | 2, 
-                      ("tcp_enqueue: could not allocate memory for zero-copy pbuf\n"));
-          goto memerr;
-        }
-        ++queuelen;
-        /* reference the non-volatile payload data */
-        p->payload = ptr;
-        seg->dataptr = ptr;
-
-        /* Concatenate the headers and data pbufs together. */
-        pbuf_cat(seg->p/*header*/, p/*data*/);
-        p = NULL;
-      }
-    }
-
-    /* Now that there are more segments queued, we check again if the
-    length of the queue exceeds the configured maximum or overflows. */
-    if ((queuelen > TCP_SND_QUEUELEN) || (queuelen > TCP_SNDQUEUELEN_OVERFLOW)) {
-      LWIP_DEBUGF(TCP_OUTPUT_DEBUG | 2, ("tcp_enqueue: queue too long %"U16_F" (%"U16_F")\n", queuelen, TCP_SND_QUEUELEN));
-      goto memerr;
-    }
-
-    seg->len = seglen;
-
-    /* build TCP header */
-    if (pbuf_header(seg->p, TCP_HLEN)) {
-      LWIP_DEBUGF(TCP_OUTPUT_DEBUG | 2, ("tcp_enqueue: no room for TCP header in pbuf.\n"));
-      TCP_STATS_INC(tcp.err);
-      goto memerr;
-    }
-    seg->tcphdr = seg->p->payload;
-    seg->tcphdr->src = htons(pcb->local_port);
-    seg->tcphdr->dest = htons(pcb->remote_port);
-    seg->tcphdr->seqno = htonl(seqno);
-    seg->tcphdr->urgp = 0;
-    TCPH_FLAGS_SET(seg->tcphdr, flags);
-    /* don't fill in tcphdr->ackno and tcphdr->wnd until later */
-
-    seg->flags = optflags;
-
-    /* Set the length of the header */
-    TCPH_HDRLEN_SET(seg->tcphdr, (5 + optlen / 4));
-    LWIP_DEBUGF(TCP_OUTPUT_DEBUG | LWIP_DBG_TRACE, ("tcp_enqueue: queueing %"U32_F":%"U32_F" (0x%"X16_F")\n",
-      ntohl(seg->tcphdr->seqno),
-      ntohl(seg->tcphdr->seqno) + TCP_TCPLEN(seg),
-      (u16_t)flags));
-
-    left -= seglen;
-    seqno += seglen;
-    ptr = (void *)((u8_t *)ptr + seglen);
-  }
-
-  /* Now that the data to be enqueued has been broken up into TCP
-  segments in the queue variable, we add them to the end of the
-  pcb->unsent queue. */
-  if (pcb->unsent == NULL) {
-    useg = NULL;
-  }
-  else {
-    for (useg = pcb->unsent; useg->next != NULL; useg = useg->next);
-  }
-  /* { useg is last segment on the unsent queue, NULL if list is empty } */
-
-  /* If there is room in the last pbuf on the unsent queue,
-  chain the first pbuf on the queue together with that. */
-  if (useg != NULL &&
-    TCP_TCPLEN(useg) != 0 &&
-    !(TCPH_FLAGS(useg->tcphdr) & (TCP_SYN | TCP_FIN)) &&
-    !(flags & (TCP_SYN | TCP_FIN)) &&
-    /* fit within max seg size */
-    (useg->len + queue->len <= pcb->mss) &&
-    /* only concatenate segments with the same options */
-    (useg->flags == queue->flags)) {
-    /* Remove TCP header from first segment of our to-be-queued list */
-    if(pbuf_header(queue->p, -(TCP_HLEN + optlen))) {
-      /* Can we cope with this failing?  Just assert for now */
-      LWIP_ASSERT("pbuf_header failed\n", 0);
-      TCP_STATS_INC(tcp.err);
-      goto memerr;
-    }
-    if (queue->p->len == 0) {
-      /* free the first (header-only) pbuf if it is now empty (contained only headers) */
-      struct pbuf *old_q = queue->p;
-      queue->p = queue->p->next;
-      old_q->next = NULL;
-      queuelen--;
-      pbuf_free(old_q);
-    }
-    LWIP_ASSERT("zero-length pbuf", (queue->p != NULL) && (queue->p->len > 0));
-    pbuf_cat(useg->p, queue->p);
-    useg->len += queue->len;
-    useg->next = queue->next;
-
-    LWIP_DEBUGF(TCP_OUTPUT_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, ("tcp_enqueue: chaining segments, new len %"U16_F"\n", useg->len));
-    if (seg == queue) {
-      seg = useg;
-      seglen = useg->len;
-    }
-    memp_free(MEMP_TCP_SEG, queue);
-  }
-  else {
-    /* empty list */
-    if (useg == NULL) {
-      /* initialize list with this segment */
-      pcb->unsent = queue;
-    }
-    /* enqueue segment */
-    else {
-      useg->next = queue;
-    }
-  }
-  if ((flags & TCP_SYN) || (flags & TCP_FIN)) {
-    ++len;
-  }
-  if (flags & TCP_FIN) {
-    pcb->flags |= TF_FIN;
-  }
-  pcb->snd_lbb += len;
-
-  pcb->snd_buf -= len;
-
-  /* update number of segments on the queues */
-  pcb->snd_queuelen = queuelen;
-  LWIP_DEBUGF(TCP_QLEN_DEBUG, ("tcp_enqueue: %"S16_F" (after enqueued)\n", pcb->snd_queuelen));
-  if (pcb->snd_queuelen != 0) {
-    LWIP_ASSERT("tcp_enqueue: valid queue length",
-      pcb->unacked != NULL || pcb->unsent != NULL);
-  }
-
-  /* Set the PSH flag in the last segment that we enqueued, but only
-  if the segment has data (indicated by seglen > 0). */
-  if (seg != NULL && seglen > 0 && seg->tcphdr != NULL && ((apiflags & TCP_WRITE_FLAG_MORE)==0)) {
-    TCPH_SET_FLAG(seg->tcphdr, TCP_PSH);
-  }
-
-  return ERR_OK;
-memerr:
-  pcb->flags |= TF_NAGLEMEMERR;
-  TCP_STATS_INC(tcp.memerr);
-
-  if (queue != NULL) {
-    tcp_segs_free(queue);
-  }
-  if (pcb->snd_queuelen != 0) {
-    LWIP_ASSERT("tcp_enqueue: valid queue length", pcb->unacked != NULL ||
-      pcb->unsent != NULL);
-  }
-  LWIP_DEBUGF(TCP_QLEN_DEBUG | LWIP_DBG_STATE, ("tcp_enqueue: %"S16_F" (with mem err)\n", pcb->snd_queuelen));
-  return ERR_MEM;
-}
-
-
-#if LWIP_TCP_TIMESTAMPS
-/* Build a timestamp option (12 bytes long) at the specified options pointer)
- *
- * @param pcb tcp_pcb
- * @param opts option pointer where to store the timestamp option
- */
-static void
-tcp_build_timestamp_option(struct tcp_pcb *pcb, u32_t *opts)
-{
-  /* Pad with two NOP options to make everything nicely aligned */
-  opts[0] = htonl(0x0101080A);
-  opts[1] = htonl(sys_now());
-  opts[2] = htonl(pcb->ts_recent);
-}
-#endif
-
-
-/**
- * Find out what we can send and send it
- *
- * @param pcb Protocol control block for the TCP connection to send data
- * @return ERR_OK if data has been sent or nothing to send
- *         another err_t on error
- */
-err_t
-tcp_output(struct tcp_pcb *pcb)
-{
-  struct pbuf *p;
-  struct tcp_hdr *tcphdr;
-  struct tcp_seg *seg, *useg;
-  u32_t wnd, snd_nxt;
-#if TCP_CWND_DEBUG
-  s16_t i = 0;
-#endif /* TCP_CWND_DEBUG */
-  u8_t optlen = 0;
-
-  /* First, check if we are invoked by the TCP input processing
-     code. If so, we do not output anything. Instead, we rely on the
-     input processing code to call us when input processing is done
-     with. */
-  if (tcp_input_pcb == pcb) {
-    return ERR_OK;
-  }
-
-  wnd = LWIP_MIN(pcb->snd_wnd, pcb->cwnd);
-
-  seg = pcb->unsent;
-
-  /* useg should point to last segment on unacked queue */
-  useg = pcb->unacked;
-  if (useg != NULL) {
-    for (; useg->next != NULL; useg = useg->next);
-  }
-
-  /* If the TF_ACK_NOW flag is set and no data will be sent (either
-   * because the ->unsent queue is empty or because the window does
-   * not allow it), construct an empty ACK segment and send it.
-   *
-   * If data is to be sent, we will just piggyback the ACK (see below).
-   */
-  if (pcb->flags & TF_ACK_NOW &&
-     (seg == NULL ||
-      ntohl(seg->tcphdr->seqno) - pcb->lastack + seg->len > wnd)) {
-#if LWIP_TCP_TIMESTAMPS
-    if (pcb->flags & TF_TIMESTAMP)
-      optlen = LWIP_TCP_OPT_LENGTH(TF_SEG_OPTS_TS);
-#endif
-    p = pbuf_alloc(PBUF_IP, TCP_HLEN + optlen, PBUF_RAM);
-    if (p == NULL) {
-      LWIP_DEBUGF(TCP_OUTPUT_DEBUG, ("tcp_output: (ACK) could not allocate pbuf\n"));
-      return ERR_BUF;
-    }
-    LWIP_DEBUGF(TCP_OUTPUT_DEBUG, 
-                ("tcp_output: sending ACK for %"U32_F"\n", pcb->rcv_nxt));
-    /* remove ACK flags from the PCB, as we send an empty ACK now */
-    pcb->flags &= ~(TF_ACK_DELAY | TF_ACK_NOW);
-
-    tcphdr = tcp_output_set_header(pcb, p, optlen, htonl(pcb->snd_nxt));
-
-    /* NB. MSS option is only sent on SYNs, so ignore it here */
-#if LWIP_TCP_TIMESTAMPS
-    pcb->ts_lastacksent = pcb->rcv_nxt;
-
-    if (pcb->flags & TF_TIMESTAMP)
-      tcp_build_timestamp_option(pcb, (u32_t *)(tcphdr + 1));
-#endif 
-
-#if CHECKSUM_GEN_TCP
-    tcphdr->chksum = inet_chksum_pseudo(p, &(pcb->local_ip), &(pcb->remote_ip),
-          IP_PROTO_TCP, p->tot_len);
-#endif
-#if LWIP_NETIF_HWADDRHINT
-    ip_output_hinted(p, &(pcb->local_ip), &(pcb->remote_ip), pcb->ttl, pcb->tos,
-        IP_PROTO_TCP, &(pcb->addr_hint));
-#else /* LWIP_NETIF_HWADDRHINT*/
-    ip_output(p, &(pcb->local_ip), &(pcb->remote_ip), pcb->ttl, pcb->tos,
-        IP_PROTO_TCP);
-#endif /* LWIP_NETIF_HWADDRHINT*/
-    pbuf_free(p);
-
-    return ERR_OK;
-  }
-
-#if TCP_OUTPUT_DEBUG
-  if (seg == NULL) {
-    LWIP_DEBUGF(TCP_OUTPUT_DEBUG, ("tcp_output: nothing to send (%p)\n",
-                                   (void*)pcb->unsent));
-  }
-#endif /* TCP_OUTPUT_DEBUG */
-#if TCP_CWND_DEBUG
-  if (seg == NULL) {
-    LWIP_DEBUGF(TCP_CWND_DEBUG, ("tcp_output: snd_wnd %"U16_F
-                                 ", cwnd %"U16_F", wnd %"U32_F
-                                 ", seg == NULL, ack %"U32_F"\n",
-                                 pcb->snd_wnd, pcb->cwnd, wnd, pcb->lastack));
-  } else {
-    LWIP_DEBUGF(TCP_CWND_DEBUG, 
-                ("tcp_output: snd_wnd %"U16_F", cwnd %"U16_F", wnd %"U32_F
-                 ", effwnd %"U32_F", seq %"U32_F", ack %"U32_F"\n",
-                 pcb->snd_wnd, pcb->cwnd, wnd,
-                 ntohl(seg->tcphdr->seqno) - pcb->lastack + seg->len,
-                 ntohl(seg->tcphdr->seqno), pcb->lastack));
-  }
-#endif /* TCP_CWND_DEBUG */
-  /* data available and window allows it to be sent? */
-  while (seg != NULL &&
-         ntohl(seg->tcphdr->seqno) - pcb->lastack + seg->len <= wnd) {
-    LWIP_ASSERT("RST not expected here!", 
-                (TCPH_FLAGS(seg->tcphdr) & TCP_RST) == 0);
-    /* Stop sending if the nagle algorithm would prevent it
-     * Don't stop:
-     * - if tcp_enqueue had a memory error before (prevent delayed ACK timeout) or
-     * - if FIN was already enqueued for this PCB (SYN is always alone in a segment -
-     *   either seg->next != NULL or pcb->unacked == NULL;
-     *   RST is no sent using tcp_enqueue/tcp_output.
-     */
-    if((tcp_do_output_nagle(pcb) == 0) &&
-      ((pcb->flags & (TF_NAGLEMEMERR | TF_FIN)) == 0)){
-      break;
-    }
-#if TCP_CWND_DEBUG
-    LWIP_DEBUGF(TCP_CWND_DEBUG, ("tcp_output: snd_wnd %"U16_F", cwnd %"U16_F", wnd %"U32_F", effwnd %"U32_F", seq %"U32_F", ack %"U32_F", i %"S16_F"\n",
-                            pcb->snd_wnd, pcb->cwnd, wnd,
-                            ntohl(seg->tcphdr->seqno) + seg->len -
-                            pcb->lastack,
-                            ntohl(seg->tcphdr->seqno), pcb->lastack, i));
-    ++i;
-#endif /* TCP_CWND_DEBUG */
-
-    pcb->unsent = seg->next;
-
-    if (pcb->state != SYN_SENT) {
-      TCPH_SET_FLAG(seg->tcphdr, TCP_ACK);
-      pcb->flags &= ~(TF_ACK_DELAY | TF_ACK_NOW);
-    }
-
-    tcp_output_segment(seg, pcb);
-    snd_nxt = ntohl(seg->tcphdr->seqno) + TCP_TCPLEN(seg);
-    if (TCP_SEQ_LT(pcb->snd_nxt, snd_nxt)) {
-      pcb->snd_nxt = snd_nxt;
-    }
-    /* put segment on unacknowledged list if length > 0 */
-    if (TCP_TCPLEN(seg) > 0) {
-      seg->next = NULL;
-      /* unacked list is empty? */
-      if (pcb->unacked == NULL) {
-        pcb->unacked = seg;
-        useg = seg;
-      /* unacked list is not empty? */
-      } else {
-        /* In the case of fast retransmit, the packet should not go to the tail
-         * of the unacked queue, but rather somewhere before it. We need to check for
-         * this case. -STJ Jul 27, 2004 */
-        if (TCP_SEQ_LT(ntohl(seg->tcphdr->seqno), ntohl(useg->tcphdr->seqno))){
-          /* add segment to before tail of unacked list, keeping the list sorted */
-          struct tcp_seg **cur_seg = &(pcb->unacked);
-          while (*cur_seg &&
-            TCP_SEQ_LT(ntohl((*cur_seg)->tcphdr->seqno), ntohl(seg->tcphdr->seqno))) {
-              cur_seg = &((*cur_seg)->next );
-          }
-          seg->next = (*cur_seg);
-          (*cur_seg) = seg;
-        } else {
-          /* add segment to tail of unacked list */
-          useg->next = seg;
-          useg = useg->next;
-        }
-      }
-    /* do not queue empty segments on the unacked list */
-    } else {
-      tcp_seg_free(seg);
-    }
-    seg = pcb->unsent;
-  }
-
-  if (seg != NULL && pcb->persist_backoff == 0 && 
-      ntohl(seg->tcphdr->seqno) - pcb->lastack + seg->len > pcb->snd_wnd) {
-    /* prepare for persist timer */
-    pcb->persist_cnt = 0;
-    pcb->persist_backoff = 1;
-  }
-
-  pcb->flags &= ~TF_NAGLEMEMERR;
-  return ERR_OK;
-}
-
-/**
- * Called by tcp_output() to actually send a TCP segment over IP.
- *
- * @param seg the tcp_seg to send
- * @param pcb the tcp_pcb for the TCP connection used to send the segment
- */
-static void
-tcp_output_segment(struct tcp_seg *seg, struct tcp_pcb *pcb)
-{
-  u16_t len;
-  struct netif *netif;
-  u32_t *opts;
-
-  /** @bug Exclude retransmitted segments from this count. */
-  snmp_inc_tcpoutsegs();
-
-  /* The TCP header has already been constructed, but the ackno and
-   wnd fields remain. */
-  seg->tcphdr->ackno = htonl(pcb->rcv_nxt);
-
-  /* advertise our receive window size in this TCP segment */
-  seg->tcphdr->wnd = htons(pcb->rcv_ann_wnd);
-
-  pcb->rcv_ann_right_edge = pcb->rcv_nxt + pcb->rcv_ann_wnd;
-
-  /* Add any requested options.  NB MSS option is only set on SYN
-     packets, so ignore it here */
-  opts = (u32_t *)(seg->tcphdr + 1);
-  if (seg->flags & TF_SEG_OPTS_MSS) {
-    TCP_BUILD_MSS_OPTION(*opts);
-    opts += 1;
-  }
-#if LWIP_TCP_TIMESTAMPS
-  pcb->ts_lastacksent = pcb->rcv_nxt;
-
-  if (seg->flags & TF_SEG_OPTS_TS) {
-    tcp_build_timestamp_option(pcb, opts);
-    opts += 3;
-  }
-#endif
-
-  /* If we don't have a local IP address, we get one by
-     calling ip_route(). */
-  if (ip_addr_isany(&(pcb->local_ip))) {
-    netif = ip_route(&(pcb->remote_ip));
-    if (netif == NULL) {
-      return;
-    }
-    ip_addr_set(&(pcb->local_ip), &(netif->ip_addr));
-  }
-
-  /* Set retransmission timer running if it is not currently enabled */
-  if(pcb->rtime == -1)
-    pcb->rtime = 0;
-
-  if (pcb->rttest == 0) {
-    pcb->rttest = tcp_ticks;
-    pcb->rtseq = ntohl(seg->tcphdr->seqno);
-
-    LWIP_DEBUGF(TCP_RTO_DEBUG, ("tcp_output_segment: rtseq %"U32_F"\n", pcb->rtseq));
-  }
-  LWIP_DEBUGF(TCP_OUTPUT_DEBUG, ("tcp_output_segment: %"U32_F":%"U32_F"\n",
-          htonl(seg->tcphdr->seqno), htonl(seg->tcphdr->seqno) +
-          seg->len));
-
-  len = (u16_t)((u8_t *)seg->tcphdr - (u8_t *)seg->p->payload);
-
-  seg->p->len -= len;
-  seg->p->tot_len -= len;
-
-  seg->p->payload = seg->tcphdr;
-
-  seg->tcphdr->chksum = 0;
-#if CHECKSUM_GEN_TCP
-  seg->tcphdr->chksum = inet_chksum_pseudo(seg->p,
-             &(pcb->local_ip),
-             &(pcb->remote_ip),
-             IP_PROTO_TCP, seg->p->tot_len);
-#endif
-  TCP_STATS_INC(tcp.xmit);
-
-#if LWIP_NETIF_HWADDRHINT
-  ip_output_hinted(seg->p, &(pcb->local_ip), &(pcb->remote_ip), pcb->ttl, pcb->tos,
-      IP_PROTO_TCP, &(pcb->addr_hint));
-#else /* LWIP_NETIF_HWADDRHINT*/
-  ip_output(seg->p, &(pcb->local_ip), &(pcb->remote_ip), pcb->ttl, pcb->tos,
-      IP_PROTO_TCP);
-#endif /* LWIP_NETIF_HWADDRHINT*/
-}
-
-/**
- * Send a TCP RESET packet (empty segment with RST flag set) either to
- * abort a connection or to show that there is no matching local connection
- * for a received segment.
- *
- * Called by tcp_abort() (to abort a local connection), tcp_input() (if no
- * matching local pcb was found), tcp_listen_input() (if incoming segment
- * has ACK flag set) and tcp_process() (received segment in the wrong state)
- *
- * Since a RST segment is in most cases not sent for an active connection,
- * tcp_rst() has a number of arguments that are taken from a tcp_pcb for
- * most other segment output functions.
- *
- * @param seqno the sequence number to use for the outgoing segment
- * @param ackno the acknowledge number to use for the outgoing segment
- * @param local_ip the local IP address to send the segment from
- * @param remote_ip the remote IP address to send the segment to
- * @param local_port the local TCP port to send the segment from
- * @param remote_port the remote TCP port to send the segment to
- */
-void
-tcp_rst(u32_t seqno, u32_t ackno,
-  struct ip_addr *local_ip, struct ip_addr *remote_ip,
-  u16_t local_port, u16_t remote_port)
-{
-  struct pbuf *p;
-  struct tcp_hdr *tcphdr;
-  p = pbuf_alloc(PBUF_IP, TCP_HLEN, PBUF_RAM);
-  if (p == NULL) {
-      LWIP_DEBUGF(TCP_DEBUG, ("tcp_rst: could not allocate memory for pbuf\n"));
-      return;
-  }
-  LWIP_ASSERT("check that first pbuf can hold struct tcp_hdr",
-              (p->len >= sizeof(struct tcp_hdr)));
-
-  tcphdr = p->payload;
-  tcphdr->src = htons(local_port);
-  tcphdr->dest = htons(remote_port);
-  tcphdr->seqno = htonl(seqno);
-  tcphdr->ackno = htonl(ackno);
-  TCPH_FLAGS_SET(tcphdr, TCP_RST | TCP_ACK);
-  tcphdr->wnd = htons(TCP_WND);
-  tcphdr->urgp = 0;
-  TCPH_HDRLEN_SET(tcphdr, 5);
-
-  tcphdr->chksum = 0;
-#if CHECKSUM_GEN_TCP
-  tcphdr->chksum = inet_chksum_pseudo(p, local_ip, remote_ip,
-              IP_PROTO_TCP, p->tot_len);
-#endif
-  TCP_STATS_INC(tcp.xmit);
-  snmp_inc_tcpoutrsts();
-   /* Send output with hardcoded TTL since we have no access to the pcb */
-  ip_output(p, local_ip, remote_ip, TCP_TTL, 0, IP_PROTO_TCP);
-  pbuf_free(p);
-  LWIP_DEBUGF(TCP_RST_DEBUG, ("tcp_rst: seqno %"U32_F" ackno %"U32_F".\n", seqno, ackno));
-}
-
-/**
- * Requeue all unacked segments for retransmission
- *
- * Called by tcp_slowtmr() for slow retransmission.
- *
- * @param pcb the tcp_pcb for which to re-enqueue all unacked segments
- */
-void
-tcp_rexmit_rto(struct tcp_pcb *pcb)
-{
-  struct tcp_seg *seg;
-
-  if (pcb->unacked == NULL) {
-    return;
-  }
-
-  /* Move all unacked segments to the head of the unsent queue */
-  for (seg = pcb->unacked; seg->next != NULL; seg = seg->next);
-  /* concatenate unsent queue after unacked queue */
-  seg->next = pcb->unsent;
-  /* unsent queue is the concatenated queue (of unacked, unsent) */
-  pcb->unsent = pcb->unacked;
-  /* unacked queue is now empty */
-  pcb->unacked = NULL;
-
-  /* increment number of retransmissions */
-  ++pcb->nrtx;
-
-  /* Don't take any RTT measurements after retransmitting. */
-  pcb->rttest = 0;
-
-  /* Do the actual retransmission */
-  tcp_output(pcb);
-}
-
-/**
- * Requeue the first unacked segment for retransmission
- *
- * Called by tcp_receive() for fast retramsmit.
- *
- * @param pcb the tcp_pcb for which to retransmit the first unacked segment
- */
-void
-tcp_rexmit(struct tcp_pcb *pcb)
-{
-  struct tcp_seg *seg;
-  struct tcp_seg **cur_seg;
-
-  if (pcb->unacked == NULL) {
-    return;
-  }
-
-  /* Move the first unacked segment to the unsent queue */
-  /* Keep the unsent queue sorted. */
-  seg = pcb->unacked;
-  pcb->unacked = seg->next;
-
-  cur_seg = &(pcb->unsent);
-  while (*cur_seg &&
-    TCP_SEQ_LT(ntohl((*cur_seg)->tcphdr->seqno), ntohl(seg->tcphdr->seqno))) {
-      cur_seg = &((*cur_seg)->next );
-  }
-  seg->next = *cur_seg;
-  *cur_seg = seg;
-
-  ++pcb->nrtx;
-
-  /* Don't take any rtt measurements after retransmitting. */
-  pcb->rttest = 0;
-
-  /* Do the actual retransmission. */
-  snmp_inc_tcpretranssegs();
-  tcp_output(pcb);
-}
-
-/**
- * Send keepalive packets to keep a connection active although
- * no data is sent over it.
- *
- * Called by tcp_slowtmr()
- *
- * @param pcb the tcp_pcb for which to send a keepalive packet
- */
-void
-tcp_keepalive(struct tcp_pcb *pcb)
-{
-  struct pbuf *p;
-  struct tcp_hdr *tcphdr;
-
-  LWIP_DEBUGF(TCP_DEBUG, ("tcp_keepalive: sending KEEPALIVE probe to %"U16_F".%"U16_F".%"U16_F".%"U16_F"\n",
-                          ip4_addr1(&pcb->remote_ip), ip4_addr2(&pcb->remote_ip),
-                          ip4_addr3(&pcb->remote_ip), ip4_addr4(&pcb->remote_ip)));
-
-  LWIP_DEBUGF(TCP_DEBUG, ("tcp_keepalive: tcp_ticks %"U32_F"   pcb->tmr %"U32_F" pcb->keep_cnt_sent %"U16_F"\n", 
-                          tcp_ticks, pcb->tmr, pcb->keep_cnt_sent));
-   
-  p = pbuf_alloc(PBUF_IP, TCP_HLEN, PBUF_RAM);
-   
-  if(p == NULL) {
-    LWIP_DEBUGF(TCP_DEBUG, 
-                ("tcp_keepalive: could not allocate memory for pbuf\n"));
-    return;
-  }
-  LWIP_ASSERT("check that first pbuf can hold struct tcp_hdr",
-              (p->len >= sizeof(struct tcp_hdr)));
-
-  tcphdr = tcp_output_set_header(pcb, p, 0, htonl(pcb->snd_nxt - 1));
-
-#if CHECKSUM_GEN_TCP
-  tcphdr->chksum = inet_chksum_pseudo(p, &pcb->local_ip, &pcb->remote_ip,
-                                      IP_PROTO_TCP, p->tot_len);
-#endif
-  TCP_STATS_INC(tcp.xmit);
-
-  /* Send output to IP */
-#if LWIP_NETIF_HWADDRHINT
-  ip_output_hinted(p, &pcb->local_ip, &pcb->remote_ip, pcb->ttl, 0, IP_PROTO_TCP,
-    &(pcb->addr_hint));
-#else /* LWIP_NETIF_HWADDRHINT*/
-  ip_output(p, &pcb->local_ip, &pcb->remote_ip, pcb->ttl, 0, IP_PROTO_TCP);
-#endif /* LWIP_NETIF_HWADDRHINT*/
-
-  pbuf_free(p);
-
-  LWIP_DEBUGF(TCP_DEBUG, ("tcp_keepalive: seqno %"U32_F" ackno %"U32_F".\n",
-                          pcb->snd_nxt - 1, pcb->rcv_nxt));
-}
-
-
-/**
- * Send persist timer zero-window probes to keep a connection active
- * when a window update is lost.
- *
- * Called by tcp_slowtmr()
- *
- * @param pcb the tcp_pcb for which to send a zero-window probe packet
- */
-void
-tcp_zero_window_probe(struct tcp_pcb *pcb)
-{
-  struct pbuf *p;
-  struct tcp_hdr *tcphdr;
-  struct tcp_seg *seg;
-
-  LWIP_DEBUGF(TCP_DEBUG, 
-              ("tcp_zero_window_probe: sending ZERO WINDOW probe to %"
-               U16_F".%"U16_F".%"U16_F".%"U16_F"\n",
-               ip4_addr1(&pcb->remote_ip), ip4_addr2(&pcb->remote_ip),
-               ip4_addr3(&pcb->remote_ip), ip4_addr4(&pcb->remote_ip)));
-
-  LWIP_DEBUGF(TCP_DEBUG, 
-              ("tcp_zero_window_probe: tcp_ticks %"U32_F
-               "   pcb->tmr %"U32_F" pcb->keep_cnt_sent %"U16_F"\n", 
-               tcp_ticks, pcb->tmr, pcb->keep_cnt_sent));
-
-  seg = pcb->unacked;
-
-  if(seg == NULL)
-    seg = pcb->unsent;
-
-  if(seg == NULL)
-    return;
-
-  p = pbuf_alloc(PBUF_IP, TCP_HLEN + 1, PBUF_RAM);
-   
-  if(p == NULL) {
-    LWIP_DEBUGF(TCP_DEBUG, ("tcp_zero_window_probe: no memory for pbuf\n"));
-    return;
-  }
-  LWIP_ASSERT("check that first pbuf can hold struct tcp_hdr",
-              (p->len >= sizeof(struct tcp_hdr)));
-
-  tcphdr = tcp_output_set_header(pcb, p, 0, seg->tcphdr->seqno);
-
-  /* Copy in one byte from the head of the unacked queue */
-  *((char *)p->payload + sizeof(struct tcp_hdr)) = *(char *)seg->dataptr;
-
-#if CHECKSUM_GEN_TCP
-  tcphdr->chksum = inet_chksum_pseudo(p, &pcb->local_ip, &pcb->remote_ip,
-                                      IP_PROTO_TCP, p->tot_len);
-#endif
-  TCP_STATS_INC(tcp.xmit);
-
-  /* Send output to IP */
-#if LWIP_NETIF_HWADDRHINT
-  ip_output_hinted(p, &pcb->local_ip, &pcb->remote_ip, pcb->ttl, 0, IP_PROTO_TCP,
-    &(pcb->addr_hint));
-#else /* LWIP_NETIF_HWADDRHINT*/
-  ip_output(p, &pcb->local_ip, &pcb->remote_ip, pcb->ttl, 0, IP_PROTO_TCP);
-#endif /* LWIP_NETIF_HWADDRHINT*/
-
-  pbuf_free(p);
-
-  LWIP_DEBUGF(TCP_DEBUG, ("tcp_zero_window_probe: seqno %"U32_F
-                          " ackno %"U32_F".\n",
-                          pcb->snd_nxt - 1, pcb->rcv_nxt));
-}
-#endif /* LWIP_TCP */