url.c

    char *path = old_conn->path; /* setup the current path pointer properly */
    char *ppath = old_conn->ppath; /* this is the modified path pointer */
    if(old_conn->proxyhost)
      free(old_conn->proxyhost);
    conn = conn_temp;        /* use this connection from now on */

    /* we need these pointers if we speak over a proxy */
    conn->hostname = conn->gname;
    conn->name = &conn->gname[old_conn->name - old_conn->gname];

    free(conn->path);    /* free the previously allocated path pointer */

    /* 'path' points to the allocated data, 'ppath' may have been advanced
       to point somewhere within the 'path' area. */
    conn->path = path; 
    conn->ppath = ppath;

    /* re-use init */
    conn->bits.reuse = TRUE; /* yes, we're re-using here */
    conn->bits.chunk = FALSE; /* always assume not chunked unless told
                                 otherwise */
    conn->maxdownload = -1;  /* might have been used previously! */

    free(old_conn);          /* we don't need this anymore */

    /*
     * If we're doing a resumed transfer, we need to setup our stuff
     * properly.
     */
    conn->resume_from = data->set.set_resume_from;
    if (conn->resume_from) {
        snprintf(resumerange, sizeof(resumerange), "%d-", conn->resume_from);
        if (conn->bits.rangestringalloc == TRUE) 
            free(conn->range);
        
        /* tell ourselves to fetch this range */
        conn->range = strdup(resumerange);
        conn->bits.use_range = TRUE;        /* enable range download */
        conn->bits.rangestringalloc = TRUE; /* mark range string allocated */
    }
    else if (data->set.set_range) {
      /* There is a range, but is not a resume, useful for random ftp access */
      conn->range = strdup(data->set.set_range);
      conn->bits.rangestringalloc = TRUE; /* mark range string allocated */
      conn->bits.use_range = TRUE;        /* enable range download */
    }
    
    *in_connect = conn;      /* return this instead! */

    infof(data, "Re-using existing connection! (#%d)\n", conn->connectindex);
  }
  else {
    /*
     * This is a brand new connection, so let's store it in the connection
     * cache of ours!
     */
    ConnectionStore(data, conn);
  }

  /*************************************************************
   * Set timeout if that is being used
   *************************************************************/
  if(data->set.timeout || data->set.connecttimeout) {
    /*************************************************************
     * Set signal handler to catch SIGALRM
     * Store the old value to be able to set it back later!
     *************************************************************/

#ifdef HAVE_SIGACTION
    struct sigaction sigact;
    sigaction(SIGALRM, NULL, &sigact);
    keep_sigact = sigact;
    keep_copysig = TRUE; /* yes, we have a copy */
    sigact.sa_handler = alarmfunc;
#ifdef SA_RESTART
    /* HPUX doesn't have SA_RESTART but defaults to that behaviour! */
    sigact.sa_flags &= ~SA_RESTART;
#endif
    /* now set the new struct */
    sigaction(SIGALRM, &sigact, NULL);
#else
    /* no sigaction(), revert to the much lamer signal() */
#ifdef HAVE_SIGNAL
    keep_sigact = signal(SIGALRM, alarmfunc);
#endif
#endif

    /* We set the timeout on the name resolving phase first, separately from
     * the download/upload part to allow a maximum time on everything. This is
     * a signal-based timeout, why it won't work and shouldn't be used in
     * multi-threaded environments. */

#ifdef HAVE_ALARM
    /* alarm() makes a signal get sent when the timeout fires off, and that
       will abort system calls */
    prev_alarm = alarm(data->set.connecttimeout?
                       data->set.connecttimeout:
                       data->set.timeout);
    /* We can expect the conn->created time to be "now", as that was just
       recently set in the beginning of this function and nothing slow
       has been done since then until now. */
#endif
  }

  /*************************************************************
   * Resolve the name of the server or proxy
   *************************************************************/
  if(!data->change.proxy) {
    /* If not connecting via a proxy, extract the port from the URL, if it is
     * there, thus overriding any defaults that might have been set above. */
    conn->port =  conn->remote_port; /* it is the same port */

    /* Resolve target host right on */
    if(!conn->hostaddr) {
      /* it might already be set if reusing a connection */
      conn->hostaddr = Curl_resolv(data, conn->name, conn->port,
                                   &conn->hostent_buf);
    }
    if(!conn->hostaddr) {
      failf(data, "Couldn't resolve host '%s'", conn->name);
      result =  CURLE_COULDNT_RESOLVE_HOST;
      /* don't return yet, we need to clean up the timeout first */
    }
  }
  else if(!conn->hostaddr) {
    /* This is a proxy that hasn't been resolved yet. It may be resolved
       if we're reusing an existing connection. */

    /* resolve proxy */
    /* it might already be set if reusing a connection */
    conn->hostaddr = Curl_resolv(data, conn->proxyhost, conn->port,
                                 &conn->hostent_buf);

    if(!conn->hostaddr) {
      failf(data, "Couldn't resolve proxy '%s'", conn->proxyhost);
      result = CURLE_COULDNT_RESOLVE_PROXY;
      /* don't return yet, we need to clean up the timeout first */
    }
  }
  Curl_pgrsTime(data, TIMER_NAMELOOKUP);
#ifdef HAVE_ALARM
  if(data->set.timeout || data->set.connecttimeout) {
#ifdef HAVE_SIGACTION
    if(keep_copysig) {
      /* we got a struct as it looked before, now put that one back nice
         and clean */
      sigaction(SIGALRM, &keep_sigact, NULL); /* put it back */
    }
#else
#ifdef HAVE_SIGNAL
    /* restore the previous SIGALRM handler */
    signal(SIGALRM, keep_sigact);
#endif
#endif
    /* switch back the alarm() to either zero or to what it was before minus
       the time we spent until now! */
    if(prev_alarm) {
      /* there was an alarm() set before us, now put it back */
      long elapsed_ms = Curl_tvdiff(Curl_tvnow(), conn->created);
      long alarm_set;

      /* the alarm period is counted in even number of seconds */
      alarm_set = prev_alarm - elapsed_ms/1000;

      if(alarm_set<=0) {
        /* if it turned negative, we should fire off a SIGALRM here, but we
           won't, and zero would be to switch it off so we never set it to
           less than 1! */
        alarm(1);
        result = CURLE_OPERATION_TIMEOUTED;
        failf(data, "Previous alarm fired off!");
      }
      else
        alarm(alarm_set);
    }
    else
      alarm(0); /* just shut it off */
  }
#endif
  if(result)
    return result;

  /*************************************************************
   * Proxy authentication
   *************************************************************/
  if(conn->bits.proxy_user_passwd) {
    char *authorization;
    snprintf(data->state.buffer, BUFSIZE, "%s:%s",
             data->state.proxyuser, data->state.proxypasswd);
    if(Curl_base64_encode(data->state.buffer, strlen(data->state.buffer),
                          &authorization) >= 0) {
      if(conn->allocptr.proxyuserpwd)
        free(conn->allocptr.proxyuserpwd);
      conn->allocptr.proxyuserpwd =
        aprintf("Proxy-authorization: Basic %s\015\012", authorization);
      free(authorization);
    }
  }

  /*************************************************************
   * Send user-agent to HTTP proxies even if the target protocol
   * isn't HTTP.
   *************************************************************/
  if((conn->protocol&PROT_HTTP) || data->change.proxy) {
    if(data->set.useragent) {
      if(conn->allocptr.uagent)
        free(conn->allocptr.uagent);
      conn->allocptr.uagent =
        aprintf("User-Agent: %s\015\012", data->set.useragent);
    }
  }

  if(-1 == conn->firstsocket) {
    /* Connect only if not already connected! */
    result = ConnectPlease(conn);
    if(CURLE_OK != result)
      return result;

    if(conn->curl_connect) {
      /* is there a connect() procedure? */

      /* set start time here for timeout purposes in the
       * connect procedure, it is later set again for the
       * progress meter purpose */
      conn->now = Curl_tvnow();

      /* Call the protocol-specific connect function */
      result = conn->curl_connect(conn);
      if(result != CURLE_OK)
        return result; /* pass back errors */
    }
  }

  Curl_pgrsTime(data, TIMER_CONNECT); /* we're connected */

  conn->now = Curl_tvnow(); /* time this *after* the connect is done */
  conn->bytecount = 0;
  conn->headerbytecount = 0;
  
  /* Figure out the ip-number and display the first host name it shows: */
#ifdef ENABLE_IPV6
  {
    char hbuf[NI_MAXHOST];
#ifdef NI_WITHSCOPEID
    const int niflags = NI_NUMERICHOST | NI_WITHSCOPEID;
#else
    const int niflags = NI_NUMERICHOST;
#endif
    struct addrinfo *ai = conn->serv_addr;

    if (getnameinfo(ai->ai_addr, ai->ai_addrlen, hbuf, sizeof(hbuf), NULL, 0,
	niflags)) {
      snprintf(hbuf, sizeof(hbuf), "?");
    }
    if (ai->ai_canonname) {
      infof(data, "Connected to %s (%s) port %d\n", ai->ai_canonname, hbuf,
            conn->port);
    } else {
      infof(data, "Connected to %s port %d\n", hbuf, conn->port);
    }
  }
#else
  {
    struct in_addr in;
    (void) memcpy(&in.s_addr, &conn->serv_addr.sin_addr, sizeof (in.s_addr));
    infof(data, "Connected to %s (%s)\n", conn->hostaddr->h_name,
#if defined(HAVE_INET_NTOA_R)
          inet_ntoa_r(in, ntoa_buf, sizeof(ntoa_buf))
#else
          inet_ntoa(in)
#endif
          );
  }
#endif

#ifdef __EMX__
  /* 20000330 mgs
   * the check is quite a hack...
   * we're calling _fsetmode to fix the problem with fwrite converting newline
   * characters (you get mangled text files, and corrupted binary files when
   * you download to stdout and redirect it to a file). */

  if ((data->set.out)->_handle == NULL) {
    _fsetmode(stdout, "b");
  }
#endif

  return CURLE_OK;
}

CURLcode Curl_connect(struct SessionHandle *data,
                      struct connectdata **in_connect)
{
  CURLcode code;
  struct connectdata *conn;

  /* call the stuff that needs to be called */
  code = CreateConnection(data, in_connect);

  if(CURLE_OK != code) {
    /* We're not allowed to return failure with memory left allocated
       in the connectdata struct, free those here */
    conn = (struct connectdata *)*in_connect;
    if(conn) {
      Curl_disconnect(conn);      /* close the connection */
      *in_connect = NULL;         /* return a NULL */
    }
  }
  return code;
}


CURLcode Curl_done(struct connectdata *conn)
{
  struct SessionHandle *data=conn->data;
  CURLcode result;

  /* cleanups done even if the connection is re-used */

  if(conn->bits.rangestringalloc) {
    free(conn->range);
    conn->bits.rangestringalloc = FALSE;
  }

  /* Cleanup possible redirect junk */
  if(conn->newurl) {
    free(conn->newurl);
    conn->newurl = NULL;
  }
 
  /* this calls the protocol-specific function pointer previously set */
  if(conn->curl_done)
    result = conn->curl_done(conn);
  else
    result = CURLE_OK;

  Curl_pgrsDone(conn); /* done with the operation */

  /* if data->set.reuse_forbid is TRUE, it means the libcurl client has
     forced us to close this no matter what we think.
    
     if conn->bits.close is TRUE, it means that the connection should be
     closed in spite of all our efforts to be nice, due to protocol
     restrictions in our or the server's end */
  if(data->set.reuse_forbid ||
     ((CURLE_OK == result) && conn->bits.close))
    result = Curl_disconnect(conn); /* close the connection */
  else
    infof(data, "Connection #%d left intact\n", conn->connectindex);

  return result;
}

CURLcode Curl_do(struct connectdata **connp)
{
  CURLcode result=CURLE_OK;
  struct connectdata *conn = *connp;
  struct SessionHandle *data=conn->data;

  if(conn->curl_do) {
    /* generic protocol-specific function pointer set in curl_connect() */
    result = conn->curl_do(conn);

    /* This was formerly done in transfer.c, but we better do it here */
    
    if((CURLE_WRITE_ERROR == result) && conn->bits.reuse) {
      /* This was a re-use of a connection and we got a write error in the
       * DO-phase. Then we DISCONNECT this connection and have another attempt
       * to CONNECT and then DO again! The retry cannot possibly find another
       * connection to re-use, since we only keep one possible connection for
       * each.  */

      infof(data, "Re-used connection seems dead, get a new one\n");

      conn->bits.close = TRUE; /* enforce close of this connetion */
      result = Curl_done(conn);   /* we are so done with this */
      if(CURLE_OK == result) {
        /* Now, redo the connect and get a new connection */
        result = Curl_connect(data, connp);
        if(CURLE_OK == result)
          /* ... finally back to actually retry the DO phase */
          result = conn->curl_do(*connp);
      }
    }
  }
  return result;
}

/*
 * local variables:
 * eval: (load-file "../curl-mode.el")
 * end:
 * vim600: fdm=marker
 * vim: et sw=2 ts=2 sts=2 tw=78
 */