ftp.c

  /* the ftp struct is already inited in Curl_ftp_connect() */
  struct FTP *ftp = conn->proto.ftp;

  /* Send any QUOTE strings? */
  if(data->set.quote) {
    if ((result = ftp_sendquote(conn, data->set.quote)) != CURLE_OK)
      return result;
  }

  /* This is a re-used connection. Since we change directory to where the
     transfer is taking place, we must now get back to the original dir
     where we ended up after login: */
  if (conn->bits.reuse && ftp->entrypath) {
    if ((result = cwd_and_mkd(conn, ftp->entrypath)) != CURLE_OK)
      return result;
  }

  {
    int i; /* counter for loop */
    for (i=0; ftp->dirs[i]; i++) {
      /* RFC 1738 says empty components should be respected too, but
         that is plain stupid since CWD can't be used with an empty argument */
      if ((result = cwd_and_mkd(conn, ftp->dirs[i])) != CURLE_OK)
        return result;
    }
  }

  /* Requested time of file or time-depended transfer? */
  if((data->set.get_filetime || data->set.timecondition) &&
     ftp->file) {
    result = ftp_getfiletime(conn, ftp->file);
    switch( result )
      {
      case CURLE_FTP_COULDNT_RETR_FILE:
      case CURLE_OK:
        if(data->set.timecondition) {
          if((data->info.filetime > 0) && (data->set.timevalue > 0)) {
            switch(data->set.timecondition) {
            case TIMECOND_IFMODSINCE:
            default:
              if(data->info.filetime < data->set.timevalue) {
                infof(data, "The requested document is not new enough\n");
                ftp->no_transfer = TRUE; /* mark this to not transfer data */
                return CURLE_OK;
              }
              break;
            case TIMECOND_IFUNMODSINCE:
              if(data->info.filetime > data->set.timevalue) {
                infof(data, "The requested document is not old enough\n");
                ftp->no_transfer = TRUE; /* mark this to not transfer data */
                return CURLE_OK;
              }
              break;
            } /* switch */
          }
          else {
            infof(data, "Skipping time comparison\n");
          }
        }
        break;
      default:
        return result;
      } /* switch */
  }

  /* If we have selected NOBODY and HEADER, it means that we only want file
     information. Which in FTP can't be much more than the file size and
     date. */
  if(data->set.no_body && data->set.include_header && ftp->file) {
    /* The SIZE command is _not_ RFC 959 specified, and therefor many servers
       may not support it! It is however the only way we have to get a file's
       size! */
    ssize_t filesize;
    ssize_t nread;
    int ftpcode;

    ftp->no_transfer = TRUE; /* this means no actual transfer is made */
    
    /* Some servers return different sizes for different modes, and thus we
       must set the proper type before we check the size */
    result = ftp_transfertype(conn, data->set.ftp_ascii);
    if(result)
      return result;

    /* failing to get size is not a serious error */
    result = ftp_getsize(conn, ftp->file, &filesize);

    if(CURLE_OK == result) {
      sprintf(buf, "Content-Length: %d\r\n", filesize);
      result = Curl_client_write(data, CLIENTWRITE_BOTH, buf, 0);
      if(result)
        return result;
    }

    /* Determine if server can respond to REST command and therefore
       whether it can do a range */
    FTPSENDF(conn, "REST 0", NULL);
    result = Curl_GetFTPResponse(&nread, conn, &ftpcode);

    if ((CURLE_OK == result) && (ftpcode == 350)) {
      result = Curl_client_write(data, CLIENTWRITE_BOTH,
                                 (char *)"Accept-ranges: bytes\r\n", 0);
      if(result)
        return result;
    }

    /* If we asked for a time of the file and we actually got one as
       well, we "emulate" a HTTP-style header in our output. */

#ifdef HAVE_STRFTIME
    if(data->set.get_filetime && (data->info.filetime>=0) ) {
      struct tm *tm;
#ifdef HAVE_LOCALTIME_R
      struct tm buffer;
      tm = (struct tm *)localtime_r((time_t *)&data->info.filetime, &buffer);
#else
      tm = localtime((time_t *)&data->info.filetime);
#endif
      /* format: "Tue, 15 Nov 1994 12:45:26 GMT" */
      strftime(buf, BUFSIZE-1, "Last-Modified: %a, %d %b %Y %H:%M:%S GMT\r\n",
               tm);
      result = Curl_client_write(data, CLIENTWRITE_BOTH, buf, 0);
      if(result)
        return result;
    }
#endif

    return CURLE_OK;
  }

  if(data->set.no_body)
    /* doesn't really transfer any data */
    ftp->no_transfer = TRUE;
  /* Get us a second connection up and connected */
  else if(data->set.ftp_use_port) {
    /* We have chosen to use the PORT command */
    result = ftp_use_port(conn);
    if(CURLE_OK == result) {
      /* we have the data connection ready */
      infof(data, "Ordered connect of the data stream with PORT!\n");
      *connected = TRUE; /* mark us "still connected" */
    }
  }
  else {
    /* We have chosen (this is default) to use the PASV command */
    result = ftp_use_pasv(conn, connected);
    if(connected)
      infof(data, "Connected the data stream with PASV!\n");
  }
  
  return result;
}

/***********************************************************************
 *
 * Curl_ftp()
 *
 * 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.
 */
CURLcode Curl_ftp(struct connectdata *conn)
{
  CURLcode retcode=CURLE_OK;
  bool connected=0;

  struct SessionHandle *data = conn->data;
  struct FTP *ftp;

  char *slash_pos;  /* position of the first '/' char in curpos */
  char *cur_pos=conn->ppath; /* current position in ppath. point at the begin
                                of next path component */
  int path_part=0;/* current path component */

  /* the ftp struct is already inited in ftp_connect() */
  ftp = conn->proto.ftp;
  conn->size = -1; /* make sure this is unknown at this point */

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

  /*  fixed : initialize ftp->dirs[xxx] to NULL !
      is done in Curl_ftp_connect() */

  /* parse the URL path into separate path components */
  while((slash_pos=strchr(cur_pos, '/'))) {
    /* 1 or 0 to indicate absolute directory */
    bool absolute_dir = (cur_pos - conn->ppath > 0) && (path_part == 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. */
      ftp->dirs[path_part] = curl_unescape(cur_pos - absolute_dir,
                                           slash_pos - cur_pos + absolute_dir);
    
      if (!ftp->dirs[path_part]) { /* run out of memory ... */
        failf(data, "no memory");
        freedirs(ftp);
        return CURLE_OUT_OF_MEMORY;
      }
    }
    else {
      cur_pos = slash_pos + 1; /* jump to the rest of the string */
      continue;
    }

    if(!retcode) {
      cur_pos = slash_pos + 1; /* jump to the rest of the string */
      if(++path_part >= (CURL_MAX_FTP_DIRDEPTH-1)) {
        /* too deep, we need the last entry to be kept NULL at all
           times to signal end of list */
        failf(data, "too deep dir hierarchy");
        freedirs(ftp);
        return CURLE_URL_MALFORMAT;
      }
    }
  }

  ftp->file = cur_pos;  /* the rest is the file name */

  if(*ftp->file) {
    ftp->file = curl_unescape(ftp->file, 0);
    if(NULL == ftp->file) {
      freedirs(ftp);
      failf(data, "no memory");
      return CURLE_OUT_OF_MEMORY;
    }
  }
  else
    ftp->file=NULL; /* instead of point to a zero byte, we make it a NULL
                       pointer */
  
  retcode = ftp_perform(conn, &connected);

  if(CURLE_OK == retcode) {
    if(connected)
      retcode = Curl_ftp_nextconnect(conn);

    if(retcode && (conn->secondarysocket >= 0)) {
      /* Failure detected, close the second socket if it was created already */
      sclose(conn->secondarysocket);
      conn->secondarysocket = -1;
    }

    if(ftp->no_transfer)
      /* no data to transfer */
      retcode=Curl_Transfer(conn, -1, -1, FALSE, NULL, -1, NULL);        
    else if(!connected)
      /* since we didn't connect now, we want do_more to get called */
      conn->bits.do_more = TRUE;
  }

  return retcode;
}

/***********************************************************************
 *
 * Curl_ftpsendf()
 *
 * Sends the formated string as a ftp command to a ftp server
 *
 * NOTE: we build the command in a fixed-length buffer, which sets length
 * restrictions on the command!
 */
CURLcode Curl_ftpsendf(struct connectdata *conn,
                       const char *fmt, ...)
{
  ssize_t bytes_written;
  char s[256];
  ssize_t write_len;
  char *sptr=s;
  CURLcode res = CURLE_OK;

  va_list ap;
  va_start(ap, fmt);
  vsnprintf(s, 250, fmt, ap);
  va_end(ap);
  
  strcat(s, "\r\n"); /* append a trailing CRLF */

  bytes_written=0;
  write_len = strlen(s);

  do {
    res = Curl_write(conn, conn->firstsocket, sptr, write_len,
                     &bytes_written);

    if(CURLE_OK != res)
      break;

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

    if(bytes_written != write_len) {
      write_len -= bytes_written;
      sptr += bytes_written;
    }
    else
      break;
  } while(1);

  return res;
}

/***********************************************************************
 *
 * Curl_ftp_disconnect()
 *
 * Disconnect from an FTP server. Cleanup protocol-specific per-connection
 * resources
 */
CURLcode Curl_ftp_disconnect(struct connectdata *conn)
{
  struct FTP *ftp= conn->proto.ftp;

  /* The FTP session may or may not have been allocated/setup at this point! */
  if(ftp) {
    if(ftp->entrypath)
      free(ftp->entrypath);
    if(ftp->cache) {
      free(ftp->cache);
      ftp->cache = NULL;
    }
    if(ftp->file) {
      free(ftp->file);
      ftp->file = NULL; /* zero */
    }
    freedirs(ftp);
  }
  return CURLE_OK;
}

/***********************************************************************
 *
 * ftp_mkd()
 *
 * Makes a directory on the FTP server.
 */
CURLcode ftp_mkd(struct connectdata *conn, char *path)
{
  CURLcode result=CURLE_OK;
  int ftpcode; /* for ftp status */
  ssize_t nread;

  /* Create a directory on the remote server */
  FTPSENDF(conn, "MKD %s", path);

  result = Curl_GetFTPResponse(&nread, conn, &ftpcode);
  if(result)
    return result;
  
  switch(ftpcode) {
  case 257:
    /* success! */
    infof( conn->data , "Created Remote Directory %s\n" , path );
    break;
  default:
    infof(conn->data, "unrecognized MKD response %d\n", result );
    result = ~CURLE_OK;
    break;
  }
  return  result;
}

/***********************************************************************
 *
 * ftp_cwd_and_mkd()
 *
 * Change to the given directory.  If the directory is not present, and we
 * have been told to allow it, then create the directory and cd to it.
 */
static CURLcode cwd_and_mkd(struct connectdata *conn, char *path)
{
  CURLcode result;
  
  result = ftp_cwd(conn, path);
  if ((CURLE_OK != result) && conn->data->set.ftp_create_missing_dirs) {
    result = ftp_mkd(conn, path);
    if ( CURLE_OK != result)
      return result;
    result = ftp_cwd(conn, path);
  }
  return result;
}

#endif /* CURL_DISABLE_FTP */