url.c

                               struct Curl_dns_entry **addr,
                               bool *async)
{
  CURLcode result=CURLE_OK;
  long shortest = 0; /* default to no timeout */

  /*************************************************************
   * Set timeout if that is being used
   *************************************************************/
  if(data->set.timeout || data->set.connecttimeout) {

    /* 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. */

    shortest = data->set.timeout; /* default to this timeout value */
    if(shortest && data->set.connecttimeout &&
       (data->set.connecttimeout < shortest))
      /* if both are set, pick the shortest */
      shortest = data->set.connecttimeout;
    else if(!shortest)
      /* if timeout is not set, use the connect timeout */
      shortest = data->set.connecttimeout;
  /* 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. */
  }

  /*************************************************************
   * Resolve the name of the server or proxy
   *************************************************************/
  if(conn->bits.reuse) {
    /* re-used connection, no resolving is necessary */
    *addr = NULL;
    /* we'll need to clear conn->dns_entry later in Curl_disconnect() */

    if(conn->bits.proxy)
      fix_hostname(data, conn, &conn->host);
  }
  else {
    /* this is a fresh connect */
    int rc;
    struct Curl_dns_entry *hostaddr;

    /* set a pointer to the hostname we display */
    fix_hostname(data, conn, &conn->host);

    if(!conn->proxy.name || !*conn->proxy.name) {
      /* 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 */
      rc = Curl_resolv_timeout(conn, conn->host.name, (int)conn->port,
                               &hostaddr, shortest);
      if(rc == CURLRESOLV_PENDING)
        *async = TRUE;

      else if (rc == CURLRESOLV_TIMEDOUT)
        result = CURLE_OPERATION_TIMEDOUT;

      else if(!hostaddr) {
        failf(data, "Couldn't resolve host '%s'", conn->host.dispname);
        result =  CURLE_COULDNT_RESOLVE_HOST;
        /* don't return yet, we need to clean up the timeout first */
      }
    }
    else {
      /* This is a proxy that hasn't been resolved yet. */

      /* IDN-fix the proxy name */
      fix_hostname(data, conn, &conn->proxy);

      /* resolve proxy */
      rc = Curl_resolv_timeout(conn, conn->proxy.name, (int)conn->port,
                               &hostaddr, shortest);

      if(rc == CURLRESOLV_PENDING)
        *async = TRUE;

      else if (rc == CURLRESOLV_TIMEDOUT)
        result = CURLE_OPERATION_TIMEDOUT;

      else if(!hostaddr) {
        failf(data, "Couldn't resolve proxy '%s'", conn->proxy.dispname);
        result = CURLE_COULDNT_RESOLVE_PROXY;
        /* don't return yet, we need to clean up the timeout first */
      }
    }
    *addr = hostaddr;
  }

  return result;
}

/*
 * Cleanup the connection just allocated before we can move along and use the
 * previously existing one.  All relevant data is copied over and old_conn is
 * ready for freeing once this function returns.
 */
static void reuse_conn(struct connectdata *old_conn,
                       struct connectdata *conn)
{
  if(old_conn->proxy.rawalloc)
    free(old_conn->proxy.rawalloc);

  /* free the SSL config struct from this connection struct as this was
     allocated in vain and is targeted for destruction */
  Curl_free_ssl_config(&old_conn->ssl_config);

  conn->data = old_conn->data;

  /* get the user+password information from the old_conn struct since it may
   * be new for this request even when we re-use an existing connection */
  conn->bits.user_passwd = old_conn->bits.user_passwd;
  if(conn->bits.user_passwd) {
    /* use the new user name and password though */
    Curl_safefree(conn->user);
    Curl_safefree(conn->passwd);
    conn->user = old_conn->user;
    conn->passwd = old_conn->passwd;
    old_conn->user = NULL;
    old_conn->passwd = NULL;
  }

  conn->bits.proxy_user_passwd = old_conn->bits.proxy_user_passwd;
  if(conn->bits.proxy_user_passwd) {
    /* use the new proxy user name and proxy password though */
    Curl_safefree(conn->proxyuser);
    Curl_safefree(conn->proxypasswd);
    conn->proxyuser = old_conn->proxyuser;
    conn->proxypasswd = old_conn->proxypasswd;
    old_conn->proxyuser = NULL;
    old_conn->proxypasswd = NULL;
  }

  /* host can change, when doing keepalive with a proxy ! */
  if(conn->bits.proxy) {
    free(conn->host.rawalloc);
    conn->host=old_conn->host;
  }
  else
    free(old_conn->host.rawalloc); /* free the newly allocated name buffer */

  /* re-use init */
  conn->bits.reuse = TRUE; /* yes, we're re-using here */

  Curl_safefree(old_conn->user);
  Curl_safefree(old_conn->passwd);
  Curl_safefree(old_conn->proxyuser);
  Curl_safefree(old_conn->proxypasswd);
  Curl_llist_destroy(old_conn->send_pipe, NULL);
  Curl_llist_destroy(old_conn->recv_pipe, NULL);
  Curl_llist_destroy(old_conn->pend_pipe, NULL);
  Curl_safefree(old_conn->master_buffer);
}

/**
 * create_conn() sets up a new connectdata struct, or re-uses an already
 * existing one, and resolves host name.
 *
 * if this function returns CURLE_OK and *async is set to TRUE, the resolve
 * response will be coming asynchronously. If *async is FALSE, the name is
 * already resolved.
 *
 * @param data The sessionhandle pointer
 * @param in_connect is set to the next connection data pointer
 * @param addr is set to the new dns entry for this connection. If this
 *        connection is re-used it will be NULL.
 * @param async is set TRUE/FALSE depending on the nature of this lookup
 * @return CURLcode
 * @see setup_conn()
 *
 * *NOTE* this function assigns the conn->data pointer!
 */

static CURLcode create_conn(struct SessionHandle *data,
                            struct connectdata **in_connect,
                            struct Curl_dns_entry **addr,
                            bool *async)
{
  CURLcode result=CURLE_OK;
  struct connectdata *conn;
  struct connectdata *conn_temp = NULL;
  size_t urllen;
  char user[MAX_CURL_USER_LENGTH];
  char passwd[MAX_CURL_PASSWORD_LENGTH];
  bool reuse;
  char *proxy = NULL;

  *addr = NULL; /* nothing yet */
  *async = FALSE;

  /*************************************************************
   * Check input data
   *************************************************************/

  if(!data->change.url)
    return CURLE_URL_MALFORMAT;

  /* First, split up the current URL in parts so that we can use the
     parts for checking against the already present connections. In order
     to not have to modify everything at once, we allocate a temporary
     connection data struct and fill in for comparison purposes. */

  conn = allocate_conn();

  /* We must set the return variable as soon as possible, so that our
     parent can cleanup any possible allocs we may have done before
     any failure */
  *in_connect = conn;

  if(!conn)
    return CURLE_OUT_OF_MEMORY;

  conn->data = data; /* Setup the association between this connection
                        and the SessionHandle */

  conn->proxytype = data->set.proxytype; /* type */

#ifdef CURL_DISABLE_PROXY

  conn->bits.proxy = FALSE;
  conn->bits.httpproxy = FALSE;
  conn->bits.proxy_user_passwd = FALSE;
  conn->bits.tunnel_proxy = FALSE;

#else /* CURL_DISABLE_PROXY */

  conn->bits.proxy = (bool)(data->set.str[STRING_PROXY] &&
                            *data->set.str[STRING_PROXY]);
  conn->bits.httpproxy = (bool)(conn->bits.proxy &&
                                (conn->proxytype == CURLPROXY_HTTP ||
                                 conn->proxytype == CURLPROXY_HTTP_1_0));
  conn->bits.proxy_user_passwd =
    (bool)(NULL != data->set.str[STRING_PROXYUSERNAME]);
  conn->bits.tunnel_proxy = data->set.tunnel_thru_httpproxy;

#endif /* CURL_DISABLE_PROXY */

  conn->bits.user_passwd = (bool)(NULL != data->set.str[STRING_USERNAME]);
  conn->bits.ftp_use_epsv = data->set.ftp_use_epsv;
  conn->bits.ftp_use_eprt = data->set.ftp_use_eprt;

  if(data->multi && Curl_multi_canPipeline(data->multi) &&
      !conn->master_buffer) {
    /* Allocate master_buffer to be used for pipelining */
    conn->master_buffer = calloc(BUFSIZE, sizeof (char));
    if(!conn->master_buffer)
      return CURLE_OUT_OF_MEMORY;
  }

  /* Initialize the pipeline lists */
  conn->send_pipe = Curl_llist_alloc((curl_llist_dtor) llist_dtor);
  conn->recv_pipe = Curl_llist_alloc((curl_llist_dtor) llist_dtor);
  conn->pend_pipe = Curl_llist_alloc((curl_llist_dtor) llist_dtor);
  if(!conn->send_pipe || !conn->recv_pipe || !conn->pend_pipe)
    return CURLE_OUT_OF_MEMORY;

  /* This initing continues below, see the comment "Continue connectdata
   * initialization here" */

  /***********************************************************
   * We need to allocate memory to store the path in. We get the size of the
   * full URL to be sure, and we need to make it at least 256 bytes since
   * other parts of the code will rely on this fact
   ***********************************************************/
#define LEAST_PATH_ALLOC 256
  urllen=strlen(data->change.url);
  if(urllen < LEAST_PATH_ALLOC)
    urllen=LEAST_PATH_ALLOC;

  /*
   * We malloc() the buffers below urllen+2 to make room for to possibilities:
   * 1 - an extra terminating zero
   * 2 - an extra slash (in case a syntax like "www.host.com?moo" is used)
   */

  Curl_safefree(data->state.pathbuffer);
  data->state.pathbuffer = malloc(urllen+2);
  if(NULL == data->state.pathbuffer)
    return CURLE_OUT_OF_MEMORY; /* really bad error */
  data->state.path = data->state.pathbuffer;

  conn->host.rawalloc = malloc(urllen+2);
  if(NULL == conn->host.rawalloc)
    return CURLE_OUT_OF_MEMORY;

  conn->host.name = conn->host.rawalloc;
  conn->host.name[0] = 0;

  result = ParseURLAndFillConnection(data, conn);
  if(result != CURLE_OK) {
      return result;
  }

#ifndef CURL_DISABLE_PROXY
  /*************************************************************
   * Extract the user and password from the authentication string
   *************************************************************/
  if(conn->bits.proxy_user_passwd) {
    result = parse_proxy_auth(data, conn);
    if(result != CURLE_OK)
        return result;
  }

  /*************************************************************
   * Detect what (if any) proxy to use
   *************************************************************/
  if(data->set.str[STRING_PROXY]) {
    proxy = strdup(data->set.str[STRING_PROXY]);
    /* if global proxy is set, this is it */
    if(NULL == proxy) {
      failf(data, "memory shortage");
      return CURLE_OUT_OF_MEMORY;
    }
  }

  if(!proxy)
    proxy = detect_proxy(conn);
  else if(data->set.str[STRING_NOPROXY]) {
    if(check_noproxy(conn->host.name, data->set.str[STRING_NOPROXY])) {
      free(proxy);  /* proxy is in exception list */
      proxy = NULL;
    }
  }
  if(proxy && !*proxy) {
    free(proxy);  /* Don't bother with an empty proxy string */
    proxy = NULL;
  }
  /* proxy must be freed later unless NULL */
  if(proxy && *proxy) {
    long bits = conn->protocol & (PROT_HTTPS|PROT_SSL|PROT_MISSING);

    if((conn->proxytype == CURLPROXY_HTTP) ||
       (conn->proxytype == CURLPROXY_HTTP_1_0)) {
      /* force this connection's protocol to become HTTP */
      conn->protocol = PROT_HTTP | bits;
      conn->bits.httpproxy = TRUE;
    }
    conn->bits.proxy = TRUE;
  }
  else {
      /* we aren't using the proxy after all... */
      conn->bits.proxy = FALSE;
      conn->bits.httpproxy = FALSE;
      conn->bits.proxy_user_passwd = FALSE;
      conn->bits.tunnel_proxy = FALSE;
  }
#endif /* CURL_DISABLE_PROXY */

  /*************************************************************
   * No protocol part in URL was used, add it!
   *************************************************************/
  if(conn->protocol&PROT_MISSING) {
    /* We're guessing prefixes here and if we're told to use a proxy or if
       we're gonna follow a Location: later or... then we need the protocol
       part added so that we have a valid URL. */
    char *reurl;

    reurl = aprintf("%s://%s", conn->protostr, data->change.url);

    if(!reurl) {
      Curl_safefree(proxy);
      return CURLE_OUT_OF_MEMORY;
    }

    data->change.url = reurl;
    data->change.url_alloc = TRUE; /* free this later */
    conn->protocol &= ~PROT_MISSING; /* switch that one off again */
  }

  /*************************************************************
   * Setup internals depending on protocol
   *************************************************************/
  result = setup_connection_internals(data, conn);
  if(result != CURLE_OK) {
    Curl_safefree(proxy);
    return result;
  }


#ifndef CURL_DISABLE_PROXY
  /***********************************************************************
   * If this is supposed to use a proxy, we need to figure out the proxy
   * host name, so that we can re-use an existing connection
   * that may exist registered to the same proxy host.
   ***********************************************************************/
  if(proxy) {
    result = parse_proxy(data, conn, proxy);
    /* parse_proxy has freed the proxy string, so don't try to use it again */
    proxy = NULL;
    if(result != CURLE_OK)
      return result;
  }
#endif /* CURL_DISABLE_PROXY */

  /***********************************************************************
   * file: is a special case in that it doesn't need a network connection
   ***********************************************************************/
#ifndef CURL_DISABLE_FILE
  if(conn->protocol & PROT_FILE) {
    bool done;
    /* this is supposed to be the connect function so we better at least check
       that the file is present here! */
    DEBUGASSERT(conn->handler->connect_it);
    result = conn->handler->connect_it(conn, &done);

    /* Setup a "faked" transfer that'll do nothing */
    if(CURLE_OK == result) {
      conn->data = data;
      conn->bits.tcpconnect = TRUE; /* we are "connected */

      ConnectionStore(data, conn);

      /*
       * Setup whatever necessary for a resumed transfer
       */
      result = setup_range(data);
      if(result) {
        DEBUGASSERT(conn->handler->done);
        /* we ignore the return code for the protocol-specific DONE */
        (void)conn->handler->done(conn, result, FALSE);
        return result;
      }

      result = Curl_setup_transfer(conn, -1, -1, FALSE,
                                   NULL, /* no download */
                                   -1, NULL); /* no upload */
    }

    return result;
  }
#endif

  /*************************************************************
   * If the protocol is using SSL and HTTP proxy is used, we set
   * the tunnel_proxy bit.
   *************************************************************/
  if((conn->protocol&PROT_SSL) && conn->bits.httpproxy)
    conn->bits.tunnel_proxy = TRUE;

  /*************************************************************
   * Parse a user name and password in the URL and strip it out
   * of the host name
   *************************************************************/
  result = parse_url_userpass(data, conn, user, passwd);
  if(result != CURLE_OK)
    return result;

  /*************************************************************
   * Figure out the remote port number and fix it in the URL
   *************************************************************/
  result = parse_remote_port(data, conn);
  if(result != CURLE_OK)
    return result;

  /*************************************************************
   * Check for an overridden user name and password, then set it
   * for use
   *************************************************************/
  override_userpass(data, conn, user, passwd);
  result = set_userpass(conn, user, passwd);
  if(result != CURLE_OK)
    return result;

  /*************************************************************
   * Check the current list of connections to see if we can
   * re-use an already existing one or if we have to create a
   * new one.
   *************************************************************/

  /* Get a cloned copy of the SSL config situation stored in the
     connection struct. But to get this going nicely, we must first make
     sure that the strings in the master copy are pointing to the correct
     strings in the session handle strings array!

     Keep in mind that the pointers in the master copy are pointing to strings
     that will be freed as part of the SessionHandle struct, but all cloned
     copies will be separately allocated.
  */
  data->set.ssl.CApath = data->set.str[STRING_SSL_CAPATH];
  data->set.ssl.CAfile = data->set.str[STRING_SSL_CAFILE];
  data->set.ssl.CRLfile = data->set.str[STRING_SSL_CRLFILE];
  data->set.ssl.issuercert = data->set.str[STRING_SSL_ISSUERCERT];
  data->set.ssl.random_file = data->set.str[STRING_SSL_RANDOM_FILE];
  data->set.ssl.egdsocket = data->set.str[STRING_SSL_EGDSOCKET];
  data->set.ssl.cipher_list = data->set.str[STRING_SSL_CIPHER_LIST];

  if(!Curl_clone_ssl_config(&data->set.ssl, &conn->ssl_config))
    return CURLE_OUT_OF_MEMORY;

  /* reuse_fresh is TRUE if we are told to use a new connection by force, but
     we only acknowledge this option if this is not a re-used connection
     already (which happens due to follow-location or during a HTTP
     authentication phase). */
  if(data->set.reuse_fresh && !data->state.this_is_a_follow)
    reuse = FALSE;
  else
    reuse = ConnectionExists(data, conn, &conn_temp);

  if(reuse) {
    /*
     * We already have a connection for this, we got the former connection
     * in the conn_temp variable and thus we need to cleanup the one we
     * just allocated before we can move along and use the previously
     * existing one.
     */
    reuse_conn(conn, conn_temp);
    free(conn);          /* we don't need this anymore */
    conn = conn_temp;
    *in_connect = conn;
    infof(data, "Re-using existing connection! (#%ld) with host %s\n",
          conn->connectindex,
          conn->proxy.name?conn->proxy.dispname:conn->host.dispname);
    /* copy this IP address to the common buffer for the easy handle so that
       the address can actually survice the removal of this connection. strcpy
       is safe since the target buffer is big enough to hold the largest
       possible IP address */
    strcpy(data->info.ip, conn->ip_addr_str);

  }
  else {
    /*
     * This is a brand new connection, so let's store it in the connection
     * cache of ours!
     */
    ConnectionStore(data, conn);
  }

  /*
   * Setup whatever necessary for a resumed transfer
   */
  result = setup_range(data);
  if(result)
    return result;

  /* Continue connectdata initialization here. */

  /*
   * Inherit the proper values from the urldata struct AFTER we have arranged
   * the persistent connection stuff
   */
  conn->fread_func = data->set.fread_func;
  conn->fread_in = data->set.in;
  conn->seek_func = data->set.seek_func;
  conn->seek_client = data->set.seek_client;

  /*************************************************************
   * Resolve the address of the server or proxy
   *************************************************************/
  result = resolve_server(data, conn, addr, async);

  return result;
}

/* setup_conn() is called after the name resolve initiated in
 * create_conn() is all done.
 *
 * NOTE: the argument 'hostaddr' is NULL when this function is called for a
 * re-used connection.
 *
 * conn->data MUST already have been setup fine (in create_conn)
 */

static CURLcode setup_conn(struct connectdata *conn,
                           struct Curl_dns_entry *hostaddr,
                           bool *protocol_done)
{
  CURLcode result=CURLE_OK;
  struct SessionHandle *data = conn->data;

  Curl_pgrsTime(data, TIMER_NAMELOOKUP);

  if(conn->protocol & PROT_FILE) {
    /* There's nothing in this function to setup if we're only doing
       a file:// transfer */
    *protocol_done = TRUE;
    return result;
  }
  *protocol_done = FALSE; /* default to not done */

  /* set proxy_connect_closed to false unconditionally already here since it
     is used strictly to provide extra information to a parent function in the
     case of proxy CONNECT failures and we must make sure we don't have it
     lingering set from a previous invoke */
  conn->bits.proxy_connect_closed = FALSE;

  /*
   * Set user-agent. Used for HTTP, but since we can attempt to tunnel
   * basically anything through a http proxy we can't limit this based on
   * protocol.
   */
  if(data->set.str[STRING_USERAGENT]) {
    Curl_safefree(conn->allocptr.uagent);
    conn->allocptr.uagent =
      aprintf("User-Agent: %s\r\n", data->set.str[STRING_USERAGENT]);
    if(!conn->allocptr.uagent)
      return CURLE_OUT_OF_MEMORY;
  }

  data->req.headerbytecount = 0;

#ifdef CURL_DO_LINEEND_CONV
  data->state.crlf_conversions = 0; /* reset CRLF conversion counter */
#endif /* CURL_DO_LINEEND_CONV */

  for(;;) {
    /* loop for CURL_SERVER_CLOSED_CONNECTION */

    if(CURL_SOCKET_BAD == conn->sock[FIRSTSOCKET]) {
      bool connected = FALSE;

      /* Connect only if not already connected!
       *
       * NOTE: hostaddr can be NULL when passed to this function, but that is
       * only for the case where we re-use an existing connection and thus
       * this code section will not be reached with hostaddr == NULL.
       */
      result = ConnectPlease(data, conn, hostaddr, &connected);

      if(connected) {
        result = Curl_protocol_connect(conn, protocol_done);
        if(CURLE_OK == result)
          conn->bits.tcpconnect = TRUE;
      }
      else
        conn->bits.tcpconnect = FALSE;

      /* if the connection was closed by the server while exchanging
         authentication informations, retry with the new set
         authentication information */
      if(conn->bits.proxy_connect_closed) {
        /* reset the error buffer */
        if(data->set.errorbuffer)
          data->set.errorbuffer[0] = '\0';
        data->state.errorbuf = FALSE;
        continue;
      }

      if(CURLE_OK != result)
        return result;
    }
    else {
      Curl_pgrsTime(data, TIMER_CONNECT); /* we're connected already */
      Curl_pgrsTime(data, TIMER_APPCONNECT); /* we're connected already */
      conn->bits.tcpconnect = TRUE;
      *protocol_done = TRUE;
      if(data->set.verbose)
        verboseconnect(conn);
    }
    /* Stop the loop now */
    break;
  }

  conn->now = Curl_tvnow(); /* time this *after* the connect is done, we
                               set this here perhaps a second time */

#ifdef __EMX__
  /*
   * This 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 result;
}

CURLcode Curl_connect(struct SessionHandle *data,
                      struct connectdata **in_connect,
                      bool *asyncp,
                      bool *protocol_done)
{
  CURLcode code;
  struct Curl_dns_entry *dns;

  *asyncp = FALSE; /* assume synchronous resolves by default */

  /* call the stuff that needs to be called */
  code = create_conn(data, in_connect, &dns, asyncp);

  if(CURLE_OK == code) {
    /* no error */
    if((*in_connect)->send_pipe->size || (*in_connect)->recv_pipe->size)
      /* pipelining */
      *protocol_done = TRUE;
    else {

      if(dns || !*asyncp)
        /* If an address is available it means that we already have the name
           resolved, OR it isn't async. if this is a re-used connection 'dns'
           will be NULL here. Continue connecting from here */
        code = setup_conn(*in_connect, dns, protocol_done);

      if(dns && code) {
        /* We have the dns entry info already but failed to connect to the
         * host and thus we must make sure to unlock the dns entry again
         * before returning failure from here.
         */
        Curl_resolv_unlock(data, dns);
      }
    }
  }

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

  return code;
}

/* Call this function after Curl_connect() has returned async=TRUE and
   then a successful name resolve has been received.

   Note: this function disconnects and frees the conn data in case of
   resolve failure */
CURLcode Curl_async_resolved(struct connectdata *conn,
                             bool *protocol_done)
{
#if defined(USE_ARES) || defined(USE_THREADING_GETHOSTBYNAME) || \
    defined(USE_THREADING_GETADDRINFO)
  CURLcode code = setup_conn(conn, conn->async.dns, protocol_done);

  if(code)
    /* We're not allowed to return failure with memory left allocated
       in the connectdata struct, free those here */
    Curl_disconnect(conn); /* close the connection */

  return code;
#else
  (void)conn;
  (void)protocol_done;
  return CURLE_OK;
#endif
}


CURLcode Curl_done(struct connectdata **connp,
                   CURLcode status,  /* an error if this is called after an
                                        error was detected */
                   bool premature)
{
  CURLcode result;
  struct connectdata *conn;
  struct SessionHandle *data;

  DEBUGASSERT(*connp);

  conn = *connp;
  data = conn->data;

  Curl_expire(data, 0); /* stop timer */

  Curl_getoff_all_pipelines(data, conn);

  if(conn->bits.done ||
     (conn->send_pipe->size + conn->recv_pipe->size != 0 &&
      !data->set.reuse_forbid &&
      !conn->bits.close))
    /* Stop if Curl_done() has already been called or pipeline
       is not empty and we do not have to close connection. */
    return CURLE_OK;

  conn->bits.done = TRUE; /* called just now! */

  /* Cleanup possible redirect junk */
  if(data->req.newurl) {
    free(data->req.newurl);
    data->req.newurl = NULL;
  }
  if(data->req.location) {
    free(data->req.location);
    data->req.location = NULL;
  }

  if(conn->dns_entry) {
    Curl_resolv_unlock(data, conn->dns_entry); /* done with this */
    conn->dns_entry = NULL;
  }

  /* this calls the protocol-specific function pointer previously set */
  if(conn->handler->done)
    result = conn->handler->done(conn, status, premature);
  else
    result = CURLE_OK;

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

  /* if the transfer was completed in a paused state there can be buffered
     data left to write and then kill */
  if(data->state.tempwrite) {
    free(data->state.tempwrite);
    data->state.tempwrite = NULL;
  }

  /* for ares-using, make sure all possible outstanding requests are properly
     cancelled before we proceed */
  ares_cancel(data->state.areschannel);

  /* 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 premature is TRUE, it means this connection was said to be DONE before
     the entire request operation is complete and thus we can't know in what
     state it is for re-using, so we're forced to close it. In a perfect world
     we can add code that keep track of if we really must close it here or not,
     but currently we have no such detail knowledge.

     connectindex == -1 here means that the connection has no spot in the
     connection cache and thus we must disconnect it here.
  */
  if(data->set.reuse_forbid || conn->bits.close || premature ||
     (-1 == conn->connectindex)) {
    CURLcode res2 = Curl_disconnect(conn); /* close the connection */

    /* If we had an error already, make sure we return that one. But
       if we got a new error, return that. */
    if(!result && res2)
      result = res2;
  }
  else {
    ConnectionDone(conn); /* the connection is no longer in use */

    /* remember the most recently used connection */
    data->state.lastconnect = conn->connectindex;

    infof(data, "Connection #%ld to host %s left intact\n",
          conn->connectindex,
          conn->bits.httpproxy?conn->proxy.dispname:conn->host.dispname);
  }

  *connp = NULL; /* to make the caller of this function better detect that
                    this was either closed or handed over to the connection
                    cache here, and therefore cannot be used from this point on
                 */

  return result;
}

/*
 * do_init() inits the readwrite session. This is inited each time (in the DO
 * function before the protocol-specific DO functions are invoked) for a
 * transfer, sometimes multiple times on the same SessionHandle. Make sure
 * nothing in here depends on stuff that are setup dynamically for the
 * transfer.
 */

static CURLcode do_init(struct connectdata *conn)
{
  struct SessionHandle *data = conn->data;
  struct SingleRequest *k = &data->req;

  conn->bits.done = FALSE; /* Curl_done() is not called yet */
  conn->bits.do_more = FALSE; /* by default there's no curl_do_more() to use */
  data->state.expect100header = FALSE;

  if(data->set.opt_no_body)
    /* in HTTP lingo, no body means using the HEAD request... */
    data->set.httpreq = HTTPREQ_HEAD;
  else if(HTTPREQ_HEAD == data->set.httpreq)
    /* ... but if unset there really is no perfect method that is the
       "opposite" of HEAD but in reality most people probably think GET
       then. The important thing is that we can't let it remain HEAD if the
       opt_no_body is set FALSE since then we'll behave wrong when getting
       HTTP. */
    data->set.httpreq = HTTPREQ_GET;

  /* NB: the content encoding software depends on this initialization */
  Curl_easy_initHandleData(data);

  k->start = Curl_tvnow(); /* start time */
  k->now = k->start;   /* current time is now */
  k->header = TRUE; /* assume header */

  k->bytecount = 0;

  k->buf = data->state.buffer;
  k->uploadbuf = data->state.uploadbuffer;
  k->hbufp = data->state.headerbuff;
  k->ignorebody=FALSE;

  Curl_pgrsTime(data, TIMER_PRETRANSFER);
  Curl_speedinit(data);

  Curl_pgrsSetUploadCounter(data, 0);
  Curl_pgrsSetDownloadCounter(data, 0);

  return CURLE_OK;
}

/*
 * do_complete is called when the DO actions are complete.
 *
 * We init chunking and trailer bits to their default values here immediately
 * before receiving any header data for the current request in the pipeline.
 */
static void do_complete(struct connectdata *conn)
{
  conn->data->req.chunk=FALSE;
  conn->data->req.trailerhdrpresent=FALSE;

  conn->data->req.maxfd = (conn->sockfd>conn->writesockfd?
                               conn->sockfd:conn->writesockfd)+1;
}

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

  /* setup and init stuff before DO starts, in preparing for the transfer */
  do_init(conn);

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

    /* This was formerly done in transfer.c, but we better do it here */
    if((CURLE_SEND_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 connection */
      result = Curl_done(&conn, result, FALSE); /* we are so done with this */

      /* conn may no longer be a good pointer */

      /*
       * According to bug report #1330310. We need to check for
       * CURLE_SEND_ERROR here as well. I figure this could happen when the
       * request failed on a FTP connection and thus Curl_done() itself tried
       * to use the connection (again). Slight Lack of feedback in the report,
       * but I don't think this extra check can do much harm.
       */
      if((CURLE_OK == result) || (CURLE_SEND_ERROR == result)) {
        bool async;
        bool protocol_done = TRUE;

        /* Now, redo the connect and get a new connection */
        result = Curl_connect(data, connp, &async, &protocol_done);
        if(CURLE_OK == result) {
          /* We have connected or sent away a name resolve query fine */

          conn = *connp; /* setup conn to again point to something nice */
          if(async) {
            /* Now, if async is TRUE here, we need to wait for the name
               to resolve */
            result = Curl_wait_for_resolv(conn, NULL);
            if(result)
              return result;

            /* Resolved, continue with the connection */
            result = Curl_async_resolved(conn, &protocol_done);
            if(result)
              return result;
          }

          /* ... finally back to actually retry the DO phase */
          result = conn->handler->do_it(conn, done);
        }
      }
    }

    if((result == CURLE_OK) && *done)
      /* do_complete must be called after the protocol-specific DO function */
      do_complete(conn);
  }
  return result;
}

CURLcode Curl_do_more(struct connectdata *conn)
{
  CURLcode result=CURLE_OK;

  if(conn->handler->do_more)
    result = conn->handler->do_more(conn);

  if(result == CURLE_OK)
    /* do_complete must be called after the protocol-specific DO function */
    do_complete(conn);