apps/plugins/text_viewer/tv_pager.h

   1 /***************************************************************************
   2  *             __________               __   ___.
   3  *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
   4  *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
   5  *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
   6  *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
   7  *                     \/            \/     \/    \/            \/
   8  * $Id$
   9  *
  10  * Copyright (C) 2002 Gilles Roux
  11  *               2003 Garrett Derner
  12  *               2010 Yoshihisa Uchida
  13  *
  14  * This program is free software; you can redistribute it and/or
  15  * modify it under the terms of the GNU General Public License
  16  * as published by the Free Software Foundation; either version 2
  17  * of the License, or (at your option) any later version.
  18  *
  19  * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
  20  * KIND, either express or implied.
  21  *
  22  ****************************************************************************/
  23 #ifndef PLUGIN_TEXT_VIEWER_PAGER_H
  24 #define PLUGIN_TEXT_VIEWER_PAGER_H
  25
  26 #include "tv_screen_pos.h"
  27
  28 /* stuff for the paging */
  29
  30 /*
  31  * initialize the pager module
  32  *
  33  * return
  34  *     true  initialize success
  35  *     false initialize failure
  36  */
  37 bool tv_init_pager(void);
  38
  39 /* finalize the pager module */
  40 void tv_finalize_pager(void);
  41
  42 /* reset the stored line positions */
  43 void tv_reset_line_positions(void);
  44
  45 /*
  46  * move to the next line
  47  *
  48  * [In] size
  49  *         the current line size
  50  */
  51 void tv_move_next_line(int size);
  52
  53 /*
  54  * return the distance from the top of the current page
  55  *
  56  * [In] offset
  57  *         the difference between the current line
  58  *
  59  * return
  60  *        difference between the current line + offset from the top of the current page
  61  */
  62 int tv_get_line_positions(int offset);
  63
  64 /* change the new page */
  65 void tv_new_page(void);
  66
  67 /*
  68  * convert the given file position to the nearest the position (page, line)
  69  *
  70  * [In] fpos
  71  *         the file position which want to convert
  72  *
  73  * [Out] pos
  74  *         result
  75  */
  76 void tv_convert_fpos(off_t fpos, struct tv_screen_pos *pos);
  77
  78 /*
  79  * move to the given page and line
  80  *
  81  * [In] page_offset
  82  *          page offset
  83  *
  84  * [In] line_offset
  85  *          line offset
  86  *
  87  * [In] whence
  88  *          SEEK_CUR  seek to the current page + offset page, the current line + offset line.
  89  *          SEEK_SET  seek to the offset page, offset line.
  90  *          SEEK_END  seek to the reading last page + offset page,
  91  *                            the last line of the reading last page + offset line.
  92  */
  93 void tv_move_screen(int page_offset, int line_offset, int whence);
  94
  95 #endif