ftp.c

     * this function. So we simply return success if no ftp pointer is set.
     */
    return CURLE_OK;

  switch(status) {
  case CURLE_BAD_DOWNLOAD_RESUME:
  case CURLE_FTP_WEIRD_PASV_REPLY:
  case CURLE_FTP_PORT_FAILED:
  case CURLE_FTP_COULDNT_SET_TYPE:
  case CURLE_FTP_COULDNT_RETR_FILE:
  case CURLE_UPLOAD_FAILED:
  case CURLE_REMOTE_ACCESS_DENIED:
  case CURLE_FILESIZE_EXCEEDED:
  case CURLE_REMOTE_FILE_NOT_FOUND:
  case CURLE_WRITE_ERROR:
    /* the connection stays alive fine even though this happened */
    /* fall-through */
  case CURLE_OK: /* doesn't affect the control connection's status */
    if(!premature) {
      ftpc->ctl_valid = was_ctl_valid;
      break;
    }
    /* until we cope better with prematurely ended requests, let them
     * fallback as if in complete failure */
  default:       /* by default, an error means the control connection is
                    wedged and should not be used anymore */
    ftpc->ctl_valid = FALSE;
    ftpc->cwdfail = TRUE; /* set this TRUE to prevent us to remember the
                             current path, as this connection is going */
    conn->bits.close = TRUE; /* marked for closure */
    result = status;      /* use the already set error code */
    break;
  }

  /* now store a copy of the directory we are in */
  if(ftpc->prevpath)
    free(ftpc->prevpath);

  if(data->set.wildcardmatch) {
    if(data->set.chunk_end && ftpc->file) {
      data->set.chunk_end(data->wildcard.customptr);
    }
    ftpc->known_filesize = -1;
  }

  /* get the "raw" path */
  path = curl_easy_unescape(data, path_to_use, 0, NULL);
  if(!path) {
    /* out of memory, but we can limp along anyway (and should try to
     * since we're in the out of memory cleanup path) */
    ftpc->prevpath = NULL; /* no path */
  }
  else {
    size_t flen = ftpc->file?strlen(ftpc->file):0; /* file is "raw" already */
    size_t dlen = strlen(path)-flen;
    if(!ftpc->cwdfail) {
      if(dlen && (data->set.ftp_filemethod != FTPFILE_NOCWD)) {
        ftpc->prevpath = path;
        if(flen)
          /* if 'path' is not the whole string */
          ftpc->prevpath[dlen]=0; /* terminate */
      }
      else {
        /* we never changed dir */
        ftpc->prevpath=strdup("");
        free(path);
      }
      if(ftpc->prevpath)
        infof(data, "Remembering we are in dir \"%s\"\n", ftpc->prevpath);
    }
    else {
      ftpc->prevpath = NULL; /* no path */
      free(path);
    }
  }
  /* free the dir tree and file parts */
  freedirs(ftpc);

#if defined(HAVE_KRB4) || defined(HAVE_GSSAPI)
  Curl_sec_fflush_fd(conn, conn->sock[SECONDARYSOCKET]);
#endif

  /* shut down the socket to inform the server we're done */

#ifdef _WIN32_WCE
  shutdown(conn->sock[SECONDARYSOCKET],2);  /* SD_BOTH */
#endif

  if(conn->sock[SECONDARYSOCKET] != CURL_SOCKET_BAD) {
    if(conn->ssl[SECONDARYSOCKET].use) {
      /* The secondary socket is using SSL so we must close down that part
         first before we close the socket for real */
      Curl_ssl_close(conn, SECONDARYSOCKET);

      /* Note that we keep "use" set to TRUE since that (next) connection is
         still requested to use SSL */
    }
    if(CURL_SOCKET_BAD != conn->sock[SECONDARYSOCKET]) {
      sclose(conn->sock[SECONDARYSOCKET]);
      conn->sock[SECONDARYSOCKET] = CURL_SOCKET_BAD;
    }
  }

  if((ftp->transfer == FTPTRANSFER_BODY) && ftpc->ctl_valid &&
     pp->pending_resp && !premature) {
    /*
     * Let's see what the server says about the transfer we just performed,
     * but lower the timeout as sometimes this connection has died while the
     * data has been transfered. This happens when doing through NATs etc that
     * abandon old silent connections.
     */
    long old_time = pp->response_time;

    pp->response_time = 60*1000; /* give it only a minute for now */
    pp->response = Curl_tvnow(); /* timeout relative now */

    result = Curl_GetFTPResponse(&nread, conn, &ftpcode);

    pp->response_time = old_time; /* set this back to previous value */

    if(!nread && (CURLE_OPERATION_TIMEDOUT == result)) {
      failf(data, "control connection looks dead");
      ftpc->ctl_valid = FALSE; /* mark control connection as bad */
      conn->bits.close = TRUE; /* mark for closure */
    }

    if(result)
      return result;

    if(!ftpc->dont_check) {
      /* 226 Transfer complete, 250 Requested file action okay, completed. */
      if((ftpcode != 226) && (ftpcode != 250)) {
        failf(data, "server did not report OK, got %d", ftpcode);
        result = CURLE_PARTIAL_FILE;
      }
    }
  }

  if(result || premature)
    /* the response code from the transfer showed an error already so no
       use checking further */
    ;
  else if(data->set.upload) {
    if((-1 != data->set.infilesize) &&
       (data->set.infilesize != *ftp->bytecountp) &&
       !data->set.crlf &&
       (ftp->transfer == FTPTRANSFER_BODY)) {
      failf(data, "Uploaded unaligned file size (%" FORMAT_OFF_T
            " out of %" FORMAT_OFF_T " bytes)",
            *ftp->bytecountp, data->set.infilesize);
      result = CURLE_PARTIAL_FILE;
    }
  }
  else {
    if((-1 != data->req.size) &&
       (data->req.size != *ftp->bytecountp) &&
#ifdef CURL_DO_LINEEND_CONV
       /* Most FTP servers don't adjust their file SIZE response for CRLFs, so
        * we'll check to see if the discrepancy can be explained by the number
        * of CRLFs we've changed to LFs.
        */
       ((data->req.size + data->state.crlf_conversions) !=
        *ftp->bytecountp) &&
#endif /* CURL_DO_LINEEND_CONV */
       (data->req.maxdownload != *ftp->bytecountp)) {
      failf(data, "Received only partial file: %" FORMAT_OFF_T " bytes",
            *ftp->bytecountp);
      result = CURLE_PARTIAL_FILE;
    }
    else if(!ftpc->dont_check &&
            !*ftp->bytecountp &&
            (data->req.size>0)) {
      failf(data, "No data was received!");
      result = CURLE_FTP_COULDNT_RETR_FILE;
    }
  }

  /* clear these for next connection */
  ftp->transfer = FTPTRANSFER_BODY;
  ftpc->dont_check = FALSE;

  /* Send any post-transfer QUOTE strings? */
  if(!status && !result && !premature && data->set.postquote)
    result = ftp_sendquote(conn, data->set.postquote);

  return result;
}

/***********************************************************************
 *
 * ftp_sendquote()
 *
 * Where a 'quote' means a list of custom commands to send to the server.
 * The quote list is passed as an argument.
 *
 * BLOCKING
 */

static
CURLcode ftp_sendquote(struct connectdata *conn, struct curl_slist *quote)
{
  struct curl_slist *item;
  ssize_t nread;
  int ftpcode;
  CURLcode result;
  struct ftp_conn *ftpc = &conn->proto.ftpc;
  struct pingpong *pp = &ftpc->pp;

  item = quote;
  while(item) {
    if(item->data) {
      char *cmd = item->data;
      bool acceptfail = FALSE;

      /* if a command starts with an asterisk, which a legal FTP command never
         can, the command will be allowed to fail without it causing any
         aborts or cancels etc. It will cause libcurl to act as if the command
         is successful, whatever the server reponds. */

      if(cmd[0] == '*') {
        cmd++;
        acceptfail = TRUE;
      }

      FTPSENDF(conn, "%s", cmd);

      pp->response = Curl_tvnow(); /* timeout relative now */

      result = Curl_GetFTPResponse(&nread, conn, &ftpcode);
      if(result)
        return result;

      if(!acceptfail && (ftpcode >= 400)) {
        failf(conn->data, "QUOT string not accepted: %s", cmd);
        return CURLE_QUOTE_ERROR;
      }
    }

    item = item->next;
  }

  return CURLE_OK;
}

/***********************************************************************
 *
 * ftp_need_type()
 *
 * Returns TRUE if we in the current situation should send TYPE
 */
static int ftp_need_type(struct connectdata *conn,
                         bool ascii_wanted)
{
  return conn->proto.ftpc.transfertype != (ascii_wanted?'A':'I');
}

/***********************************************************************
 *
 * ftp_nb_type()
 *
 * Set TYPE. We only deal with ASCII or BINARY so this function
 * sets one of them.
 * If the transfer type is not sent, simulate on OK response in newstate
 */
static CURLcode ftp_nb_type(struct connectdata *conn,
                            bool ascii, ftpstate newstate)
{
  struct ftp_conn *ftpc = &conn->proto.ftpc;
  CURLcode result;
  char want = (char)(ascii?'A':'I');

  if(ftpc->transfertype == want) {
    state(conn, newstate);
    return ftp_state_type_resp(conn, 200, newstate);
  }

  PPSENDF(&ftpc->pp, "TYPE %c", want);
  state(conn, newstate);

  /* keep track of our current transfer type */
  ftpc->transfertype = want;
  return CURLE_OK;
}

/***************************************************************************
 *
 * ftp_pasv_verbose()
 *
 * This function only outputs some informationals about this second connection
 * when we've issued a PASV command before and thus we have connected to a
 * possibly new IP address.
 *
 */
#ifndef CURL_DISABLE_VERBOSE_STRINGS
static void
ftp_pasv_verbose(struct connectdata *conn,
                 Curl_addrinfo *ai,
                 char *newhost, /* ascii version */
                 int port)
{
  char buf[256];
  Curl_printable_address(ai, buf, sizeof(buf));
  infof(conn->data, "Connecting to %s (%s) port %d\n", newhost, buf, port);
}
#endif

/*
  Check if this is a range download, and if so, set the internal variables
  properly.
 */

static CURLcode ftp_range(struct connectdata *conn)
{
  curl_off_t from, to;
  char *ptr;
  char *ptr2;
  struct SessionHandle *data = conn->data;
  struct ftp_conn *ftpc = &conn->proto.ftpc;

  if(data->state.use_range && data->state.range) {
    from=curlx_strtoofft(data->state.range, &ptr, 0);
    while(*ptr && (ISSPACE(*ptr) || (*ptr=='-')))
      ptr++;
    to=curlx_strtoofft(ptr, &ptr2, 0);
    if(ptr == ptr2) {
      /* we didn't get any digit */
      to=-1;
    }
    if((-1 == to) && (from>=0)) {
      /* X - */
      data->state.resume_from = from;
      DEBUGF(infof(conn->data, "FTP RANGE %" FORMAT_OFF_T " to end of file\n",
                   from));
    }
    else if(from < 0) {
      /* -Y */
      data->req.maxdownload = -from;
      data->state.resume_from = from;
      DEBUGF(infof(conn->data, "FTP RANGE the last %" FORMAT_OFF_T " bytes\n",
                   -from));
    }
    else {
      /* X-Y */
      data->req.maxdownload = (to-from)+1; /* include last byte */
      data->state.resume_from = from;
      DEBUGF(infof(conn->data, "FTP RANGE from %" FORMAT_OFF_T
                   " getting %" FORMAT_OFF_T " bytes\n",
                   from, data->req.maxdownload));
    }
    DEBUGF(infof(conn->data, "range-download from %" FORMAT_OFF_T
                 " to %" FORMAT_OFF_T ", totally %" FORMAT_OFF_T " bytes\n",
                 from, to, data->req.maxdownload));
    ftpc->dont_check = TRUE; /* dont check for successful transfer */
  }
  else
    data->req.maxdownload = -1;
  return CURLE_OK;
}


/*
 * ftp_nextconnect()
 *
 * This function shall be called when the second FTP (data) connection is
 * connected.
 */

static CURLcode ftp_nextconnect(struct connectdata *conn)
{
  struct SessionHandle *data=conn->data;
  struct ftp_conn *ftpc = &conn->proto.ftpc;
  CURLcode result = CURLE_OK;

  /* the ftp struct is inited in ftp_connect() */
  struct FTP *ftp = data->state.proto.ftp;

  DEBUGF(infof(data, "DO-MORE phase starts\n"));

  if(ftp->transfer <= FTPTRANSFER_INFO) {
    /* a transfer is about to take place, or if not a file name was given
       so we'll do a SIZE on it later and then we need the right TYPE first */

    if(data->set.upload) {
      result = ftp_nb_type(conn, data->set.prefer_ascii, FTP_STOR_TYPE);
      if(result)
        return result;
    }
    else {
      /* download */
      ftp->downloadsize = -1; /* unknown as of yet */

      result = ftp_range(conn);
      if(result)
        ;
      else if(data->set.ftp_list_only || !ftpc->file) {
        /* The specified path ends with a slash, and therefore we think this
           is a directory that is requested, use LIST. But before that we
           need to set ASCII transfer mode. */

        /* But only if a body transfer was requested. */
        if(ftp->transfer == FTPTRANSFER_BODY) {
          result = ftp_nb_type(conn, TRUE, FTP_LIST_TYPE);
          if(result)
            return result;
        }
        /* otherwise just fall through */
      }
      else {
        result = ftp_nb_type(conn, data->set.prefer_ascii, FTP_RETR_TYPE);
        if(result)
          return result;
      }
    }
    result = ftp_easy_statemach(conn);
  }

  if((result == CURLE_OK) && (ftp->transfer != FTPTRANSFER_BODY))
    /* no data to transfer. FIX: it feels like a kludge to have this here
       too! */
    Curl_setup_transfer(conn, -1, -1, FALSE, NULL, -1, NULL);

  /* end of transfer */
  DEBUGF(infof(data, "DO-MORE phase ends with %d\n", (int)result));

  return result;
}



/***********************************************************************
 *
 * ftp_perform()
 *
 * This is the actual DO function for FTP. Get a file/directory according to
 * the options previously setup.
 */

static
CURLcode ftp_perform(struct connectdata *conn,
                     bool *connected,  /* connect status after PASV / PORT */
                     bool *dophase_done)
{
  /* this is FTP and no proxy */
  CURLcode result=CURLE_OK;

  DEBUGF(infof(conn->data, "DO phase starts\n"));

  if(conn->data->set.opt_no_body) {
    /* requested no body means no transfer... */
    struct FTP *ftp = conn->data->state.proto.ftp;
    ftp->transfer = FTPTRANSFER_INFO;
  }


  *dophase_done = FALSE; /* not done yet */

  /* start the first command in the DO phase */
  result = ftp_state_quote(conn, TRUE, FTP_QUOTE);
  if(result)
    return result;

  /* run the state-machine */
  if(conn->data->state.used_interface == Curl_if_multi)
    result = ftp_multi_statemach(conn, dophase_done);
  else {
    result = ftp_easy_statemach(conn);
    *dophase_done = TRUE; /* with the easy interface we are done here */
  }
  *connected = conn->bits.tcpconnect;

  if(*dophase_done)
    DEBUGF(infof(conn->data, "DO phase is complete\n"));

  return result;
}

static void wc_data_dtor(void *ptr)
{
  struct ftp_wc_tmpdata *tmp = ptr;
  if(tmp)
    Curl_ftp_parselist_data_free(&tmp->parser);
  Curl_safefree(tmp);
}

static CURLcode init_wc_data(struct connectdata *conn)
{
  char *last_slash;
  char *path = conn->data->state.path;
  struct WildcardData *wildcard = &(conn->data->wildcard);
  CURLcode ret = CURLE_OK;
  struct ftp_wc_tmpdata *ftp_tmp;

  last_slash = strrchr(conn->data->state.path, '/');
  if(last_slash) {
    last_slash++;
    if(last_slash[0] == '\0') {
      wildcard->state = CURLWC_CLEAN;
      ret = ftp_parse_url_path(conn);
      return ret;
    }
    else {
      wildcard->pattern = strdup(last_slash);
      if (!wildcard->pattern)
        return CURLE_OUT_OF_MEMORY;
      last_slash[0] = '\0'; /* cut file from path */
    }
  }
  else { /* there is only 'wildcard pattern' or nothing */
    if(path[0]) {
      wildcard->pattern = strdup(path);
      if (!wildcard->pattern)
        return CURLE_OUT_OF_MEMORY;
      path[0] = '\0';
    }
    else { /* only list */
      wildcard->state = CURLWC_CLEAN;
      ret = ftp_parse_url_path(conn);
      return ret;
    }
  }

  /* program continues only if URL is not ending with slash, allocate needed
     resources for wildcard transfer */

  /* allocate ftp protocol specific temporary wildcard data */
  ftp_tmp = malloc(sizeof(struct ftp_wc_tmpdata));
  if(!ftp_tmp) {
    return CURLE_OUT_OF_MEMORY;
  }

  /* INITIALIZE parselist structure */
  ftp_tmp->parser = Curl_ftp_parselist_data_alloc();
  if(!ftp_tmp->parser) {
    free(ftp_tmp);
    return CURLE_OUT_OF_MEMORY;
  }

  wildcard->tmp = ftp_tmp; /* put it to the WildcardData tmp pointer */
  wildcard->tmp_dtor = wc_data_dtor;

  /* wildcard does not support NOCWD option (assert it?) */
  if(conn->data->set.ftp_filemethod == FTPFILE_NOCWD)
    conn->data->set.ftp_filemethod = FTPFILE_MULTICWD;

  /* try to parse ftp url */
  ret = ftp_parse_url_path(conn);
  if(ret) {
    return ret;
  }

  /* backup old write_function */
  ftp_tmp->backup.write_function = conn->data->set.fwrite_func;
  /* parsing write function (callback included directly from ftplistparser.c) */
  conn->data->set.fwrite_func = Curl_ftp_parselist;
  /* backup old file descriptor */
  ftp_tmp->backup.file_descriptor = conn->data->set.out;
  /* let the writefunc callback know what curl pointer is working with */
  conn->data->set.out = conn;

  wildcard->path = strdup(conn->data->state.path);
  if(!wildcard->path) {
    return CURLE_OUT_OF_MEMORY;
  }

  infof(conn->data, "Wildcard - Parsing started\n");
  return CURLE_OK;
}

static CURLcode wc_statemach(struct connectdata *conn)
{
  struct ftp_conn *ftpc = &conn->proto.ftpc;
  struct WildcardData *wildcard = &(conn->data->wildcard);
  struct ftp_wc_tmpdata *ftp_tmp = wildcard->tmp;
  char *tmp_path;
  CURLcode ret = CURLE_OK;
  long userresponse = 0;
  switch (wildcard->state) {
  case CURLWC_INIT:
    ret = init_wc_data(conn);
    if(wildcard->state == CURLWC_CLEAN)
      /* only listing! */
      break;
    else
      wildcard->state = ret ? CURLWC_ERROR : CURLWC_MATCHING;
    break;

  case CURLWC_MATCHING:
    /* In this state is LIST response successfully parsed, so lets restore
       previous WRITEFUNCTION callback and WRITEDATA pointer */
    ftp_tmp = wildcard->tmp;
    conn->data->set.fwrite_func = ftp_tmp->backup.write_function;
    conn->data->set.out = ftp_tmp->backup.file_descriptor;
    wildcard->state = CURLWC_DOWNLOADING;

    if(Curl_ftp_parselist_geterror(ftp_tmp->parser)) {
      /* error found in LIST parsing */
      wildcard->state = CURLWC_CLEAN;
      return wc_statemach(conn);
    }
    else if(wildcard->filelist->size == 0) {
      /* no corresponding file */
      wildcard->state = CURLWC_CLEAN;
      return CURLE_REMOTE_FILE_NOT_FOUND;
    }
    ret = wc_statemach(conn);
    break;

  case CURLWC_DOWNLOADING: {
    /* filelist has at least one file, lets get first one */
    struct curl_fileinfo *finfo = wildcard->filelist->head->ptr;
    tmp_path = malloc(strlen(conn->data->state.path) +
                      strlen(finfo->filename) + 1);
    if(!tmp_path) {
      return CURLE_OUT_OF_MEMORY;
    }

    tmp_path[0] = 0;
    /* make full path to matched file */
    strcat(tmp_path, wildcard->path);
    strcat(tmp_path, finfo->filename);
    /* switch default "state.pathbuffer" and tmp_path, good to see
       ftp_parse_url_path function to understand this trick */
    if(conn->data->state.pathbuffer)
      free(conn->data->state.pathbuffer);
    conn->data->state.pathbuffer = tmp_path;
    conn->data->state.path = tmp_path;

    infof(conn->data, "Wildcard - START of \"%s\"\n", finfo->filename);
    if(conn->data->set.chunk_bgn) {
      userresponse = conn->data->set.chunk_bgn(
          finfo, wildcard->customptr, (int)wildcard->filelist->size);
      switch(userresponse) {
      case CURL_CHUNK_BGN_FUNC_SKIP:
        infof(conn->data, "Wildcard - \"%s\" skipped by user\n",
              finfo->filename);
        wildcard->state = CURLWC_SKIP;
        return wc_statemach(conn);
      case CURL_CHUNK_BGN_FUNC_FAIL:
        return CURLE_CHUNK_FAILED;
      }
    }

    if(finfo->filetype != CURLFILETYPE_FILE) {
      wildcard->state = CURLWC_SKIP;
      return wc_statemach(conn);
    }

    if(finfo->flags & CURLFINFOFLAG_KNOWN_SIZE)
      ftpc->known_filesize = finfo->size;

    ret = ftp_parse_url_path(conn);
    if(ret) {
      return ret;
    }

    /* we don't need the Curl_fileinfo of first file anymore */
    Curl_llist_remove(wildcard->filelist, wildcard->filelist->head, NULL);

    if(wildcard->filelist->size == 0) { /* remains only one file to down. */
      wildcard->state = CURLWC_CLEAN;
      /* after that will be ftp_do called once again and no transfer
         will be done because of CURLWC_CLEAN state */
      return CURLE_OK;
    }
  } break;

  case CURLWC_SKIP: {
    if(conn->data->set.chunk_end)
      conn->data->set.chunk_end(conn->data->wildcard.customptr);
    Curl_llist_remove(wildcard->filelist, wildcard->filelist->head, NULL);
    wildcard->state = (wildcard->filelist->size == 0) ?
                      CURLWC_CLEAN : CURLWC_DOWNLOADING;
    ret = wc_statemach(conn);
  } break;

  case CURLWC_CLEAN:
    ret = CURLE_OK;
    if(ftp_tmp) {
      ret = Curl_ftp_parselist_geterror(ftp_tmp->parser);
    }
    wildcard->state = ret ? CURLWC_ERROR : CURLWC_DONE;
    break;

  case CURLWC_DONE:
  case CURLWC_ERROR:
    break;
  }

  return ret;
}

/***********************************************************************
 *
 * ftp_do()
 *
 * This function is registered as 'curl_do' function. It decodes the path
 * parts etc as a wrapper to the actual DO function (ftp_perform).
 *
 * The input argument is already checked for validity.
 */
static CURLcode ftp_do(struct connectdata *conn, bool *done)
{
  CURLcode retcode = CURLE_OK;

  *done = FALSE; /* default to false */

  /*
    Since connections can be re-used between SessionHandles, this might be a
    connection already existing but on a fresh SessionHandle struct so we must
    make sure we have a good 'struct FTP' to play with. For new connections,
    the struct FTP is allocated and setup in the ftp_connect() function.
  */
  Curl_reset_reqproto(conn);
  retcode = ftp_init(conn);
  if(retcode)
    return retcode;

  if(conn->data->set.wildcardmatch) {
    retcode = wc_statemach(conn);
    if(conn->data->wildcard.state == CURLWC_SKIP ||
      conn->data->wildcard.state == CURLWC_DONE) {
      /* do not call ftp_regular_transfer */
      return CURLE_OK;
    }
    if(retcode) /* error, loop or skipping the file */
      return retcode;
  }
  else { /* no wildcard FSM needed */
    retcode = ftp_parse_url_path(conn);
    if(retcode)
      return retcode;
  }

  retcode = ftp_regular_transfer(conn, done);

  return retcode;
}


CURLcode Curl_ftpsendf(struct connectdata *conn,
                       const char *fmt, ...)
{
  ssize_t bytes_written;
#define SBUF_SIZE 1024
  char s[SBUF_SIZE];
  size_t write_len;
  char *sptr=s;
  CURLcode res = CURLE_OK;
#if defined(HAVE_KRB4) || defined(HAVE_GSSAPI)
  enum protection_level data_sec = conn->data_prot;
#endif

  va_list ap;
  va_start(ap, fmt);
  vsnprintf(s, SBUF_SIZE-3, fmt, ap);
  va_end(ap);

  strcat(s, "\r\n"); /* append a trailing CRLF */

  bytes_written=0;
  write_len = strlen(s);

#ifdef CURL_DOES_CONVERSIONS
  res = Curl_convert_to_network(conn->data, s, write_len);
  /* Curl_convert_to_network calls failf if unsuccessful */
  if(res != CURLE_OK) {
    return(res);
  }
#endif /* CURL_DOES_CONVERSIONS */

  for(;;) {
#if defined(HAVE_KRB4) || defined(HAVE_GSSAPI)
    conn->data_prot = prot_cmd;
#endif
    res = Curl_write(conn, conn->sock[FIRSTSOCKET], sptr, write_len,
                     &bytes_written);
#if defined(HAVE_KRB4) || defined(HAVE_GSSAPI)
    conn->data_prot = data_sec;
#endif

    if(CURLE_OK != res)
      break;

    if(conn->data->set.verbose)
      Curl_debug(conn->data, CURLINFO_HEADER_OUT,
                 sptr, (size_t)bytes_written, conn);

    if(bytes_written != (ssize_t)write_len) {
      write_len -= bytes_written;
      sptr += bytes_written;
    }
    else
      break;
  }

  return res;
}

/***********************************************************************
 *
 * ftp_quit()
 *
 * This should be called before calling sclose() on an ftp control connection
 * (not data connections). We should then wait for the response from the
 * server before returning. The calling code should then try to close the
 * connection.
 *
 */
static CURLcode ftp_quit(struct connectdata *conn)
{
  CURLcode result = CURLE_OK;

  if(conn->proto.ftpc.ctl_valid) {
    PPSENDF(&conn->proto.ftpc.pp, "QUIT", NULL);
    state(conn, FTP_QUIT);

    result = ftp_easy_statemach(conn);
  }

  return result;
}

/***********************************************************************
 *
 * ftp_disconnect()
 *
 * Disconnect from an FTP server. Cleanup protocol-specific per-connection
 * resources. BLOCKING.
 */
static CURLcode ftp_disconnect(struct connectdata *conn)
{
  struct ftp_conn *ftpc= &conn->proto.ftpc;
  struct pingpong *pp = &ftpc->pp;

  /* We cannot send quit unconditionally. If this connection is stale or
     bad in any way, sending quit and waiting around here will make the
     disconnect wait in vain and cause more problems than we need to.

     ftp_quit() will check the state of ftp->ctl_valid. If it's ok it
     will try to send the QUIT command, otherwise it will just return.
  */

  /* The FTP session may or may not have been allocated/setup at this point! */
  (void)ftp_quit(conn); /* ignore errors on the QUIT */

  if(ftpc->entrypath) {
    struct SessionHandle *data = conn->data;
    if(data->state.most_recent_ftp_entrypath == ftpc->entrypath) {
      data->state.most_recent_ftp_entrypath = NULL;
    }
    free(ftpc->entrypath);
    ftpc->entrypath = NULL;
  }

  freedirs(ftpc);
  if(ftpc->prevpath) {
    free(ftpc->prevpath);
    ftpc->prevpath = NULL;
  }
  if(ftpc->server_os) {
    free(ftpc->server_os);
    ftpc->server_os = NULL;
  }

  Curl_pp_disconnect(pp);

  return CURLE_OK;
}

/***********************************************************************
 *
 * ftp_parse_url_path()
 *
 * Parse the URL path into separate path components.
 *
 */
static
CURLcode ftp_parse_url_path(struct connectdata *conn)
{
  struct SessionHandle *data = conn->data;
  /* the ftp struct is already inited in ftp_connect() */
  struct FTP *ftp = data->state.proto.ftp;
  struct ftp_conn *ftpc = &conn->proto.ftpc;
  const char *slash_pos;  /* position of the first '/' char in curpos */
  const char *path_to_use = data->state.path;
  const char *cur_pos;
  const char *filename = NULL;

  cur_pos = path_to_use; /* current position in path. point at the begin
                            of next path component */

  ftpc->ctl_valid = FALSE;
  ftpc->cwdfail = FALSE;

  switch(data->set.ftp_filemethod) {
  case FTPFILE_NOCWD:
    /* fastest, but less standard-compliant */

    /*
      The best time to check whether the path is a file or directory is right
      here. so:

      the first condition in the if() right here, is there just in case
      someone decides to set path to NULL one day
   */
    if(data->state.path &&
       data->state.path[0] &&
       (data->state.path[strlen(data->state.path) - 1] != '/') )
      filename = data->state.path;  /* this is a full file path */
      /*
        ftpc->file is not used anywhere other than for operations on a file.
        In other words, never for directory operations.
        So we can safely leave filename as NULL here and use it as a
        argument in dir/file decisions.
      */
    break;

  case FTPFILE_SINGLECWD:
    /* get the last slash */
    if(!path_to_use[0]) {
      /* no dir, no file */
      ftpc->dirdepth = 0;
      break;
    }
    slash_pos=strrchr(cur_pos, '/');
    if(slash_pos || !*cur_pos) {
      ftpc->dirs = calloc(1, sizeof(ftpc->dirs[0]));
      if(!ftpc->dirs)
        return CURLE_OUT_OF_MEMORY;

      ftpc->dirs[0] = curl_easy_unescape(conn->data, slash_pos ? cur_pos : "/",
                                         slash_pos?(int)(slash_pos-cur_pos):1,
                                         NULL);
      if(!ftpc->dirs[0]) {
        freedirs(ftpc);
        return CURLE_OUT_OF_MEMORY;
      }
      ftpc->dirdepth = 1; /* we consider it to be a single dir */
      filename = slash_pos ? slash_pos+1 : cur_pos; /* rest is file name */
    }
    else
      filename = cur_pos;  /* this is a file name only */
    break;

  default: /* allow pretty much anything */
  case FTPFILE_MULTICWD:
    ftpc->dirdepth = 0;
    ftpc->diralloc = 5; /* default dir depth to allocate */
    ftpc->dirs = calloc(ftpc->diralloc, sizeof(ftpc->dirs[0]));
    if(!ftpc->dirs)
      return CURLE_OUT_OF_MEMORY;

    /* we have a special case for listing the root dir only */
    if(strequal(path_to_use, "/")) {
      cur_pos++; /* make it point to the zero byte */
      ftpc->dirs[0] = strdup("/");
      ftpc->dirdepth++;
    }
    else {
      /* parse the URL path into separate path components */
      while((slash_pos = strchr(cur_pos, '/')) != NULL) {
        /* 1 or 0 to indicate absolute directory */
        bool absolute_dir = (bool)((cur_pos - data->state.path > 0) &&
                                   (ftpc->dirdepth == 0));

        /* seek out the next path component */
        if(slash_pos-cur_pos) {
          /* we skip empty path components, like "x//y" since the FTP command
             CWD requires a parameter and a non-existant parameter a) doesn't
             work on many servers and b) has no effect on the others. */
          int len = (int)(slash_pos - cur_pos + absolute_dir);
          ftpc->dirs[ftpc->dirdepth] =
            curl_easy_unescape(conn->data, cur_pos - absolute_dir, len, NULL);
          if(!ftpc->dirs[ftpc->dirdepth]) { /* run out of memory ... */
            failf(data, "no memory");
            freedirs(ftpc);
            return CURLE_OUT_OF_MEMORY;
          }
          if(isBadFtpString(ftpc->dirs[ftpc->dirdepth])) {
            free(ftpc->dirs[ftpc->dirdepth]);
            freedirs(ftpc);
            return CURLE_URL_MALFORMAT;
          }
        }
        else {
          cur_pos = slash_pos + 1; /* jump to the rest of the string */
          continue;
        }

        cur_pos = slash_pos + 1; /* jump to the rest of the string */
        if(++ftpc->dirdepth >= ftpc->diralloc) {
          /* enlarge array */
          char *bigger;
          ftpc->diralloc *= 2; /* double the size each time */
          bigger = realloc(ftpc->dirs, ftpc->diralloc * sizeof(ftpc->dirs[0]));
          if(!bigger) {
            freedirs(ftpc);
            return CURLE_OUT_OF_MEMORY;
          }
          ftpc->dirs = (char **)bigger;