reworks text viewer plugin. (FS#11209)

new text viewer plugin: text_viewer.rock.

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@26571 a1c6a512-1295-4272-9138-f99709370657

apps/plugins/text_viewer/tv_reader.h

@@ -0,0 +1,102 @@
+/***************************************************************************
+ *             __________               __   ___.
+ *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
+ *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
+ *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
+ *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
+ *                     \/            \/     \/    \/            \/
+ * $Id$
+ *
+ * Copyright (C) 2002 Gilles Roux
+ *               2003 Garrett Derner
+ *               2010 Yoshihisa Uchida
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
+ * KIND, either express or implied.
+ *
+ ****************************************************************************/
+#ifndef PLUGIN_TEXT_VIEWER_READER_H
+#define PLUGIN_TEXT_VIEWER_READER_H
+
+/* stuff for the reading file */
+
+/*
+ * initialize the reader module
+ *
+ * [In] buf
+ *          the start pointer of the buffer
+ *
+ * [In] size
+ *          enabled buffer size
+ *
+ * [Out] used_size
+ *          the size of the buffer which the pager uses
+ *
+ * return
+ *     true  initialize success
+ *     false initialize failure
+ */
+bool tv_init_reader(unsigned char *buf, size_t bufsize, size_t *used_size);
+
+/* finalize the reader module */
+void tv_finalize_reader(void);
+
+/*
+ * return the file size
+ *
+ * return
+ *     file size
+ *
+ * Note: when the file is UTF-8 file with BOM, if the encoding of the text viewer is UTF-8,
+ * then file size decreases only BOM size.
+ */
+off_t tv_get_file_size(void);
+
+/*
+ * return the whether is the end of file or not
+ *
+ * return
+ *     true  EOF
+ *     false not EOF
+ */
+bool tv_is_eof(void);
+
+/*
+ * return the current file position
+ *
+ * return
+ *     the current file position
+ */
+off_t tv_get_current_file_pos(void);
+
+/*
+ * return the bufer which store text data
+ *
+ * [Out] bufsize
+ *          buffer size
+ *
+ * return
+ *     the pointer of the buffer
+ */
+const unsigned char *tv_get_buffer(ssize_t *bufsize);
+
+/*
+ * seek to the given offset
+ *
+ * [In] offset
+ *          offset size
+ *
+ * [In] whence
+ *          SEEK_CUR  seek to the current position + offset.
+ *          SEEK_SET  seek to the offset.
+ *
+ * Note: whence supports SEEK_CUR and SEEK_SET only.
+ */
+void tv_seek(off_t offset, int whence);
+
+#endif