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_text_reader.h

@@ -0,0 +1,101 @@
+/***************************************************************************
+ *             __________               __   ___.
+ *   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_TEXT_READER_H
+#define PLUGIN_TEXT_VIEWER_TEXT_READER_H
+
+/*
+ * initialize the text 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_text_reader(unsigned char *buf, size_t bufsize, size_t *used_size);
+
+/* finalize the text reader module */
+void tv_finalize_text_reader(void);
+
+/*
+ * set the read conditions
+ *
+ * [In] blocks
+ *          block count
+ *
+ * [In] width
+ *          block width
+ */
+void tv_set_read_conditions(int blocks, int width);
+
+/*
+ * return the total text size
+ *
+ * return
+ *     the total text size
+ */
+off_t tv_get_total_text_size(void);
+
+/*
+ * get the text of the next line
+ *
+ * [Out] buf
+ *           the pointer of the pointer which store the text
+ *
+ * return
+ *     true   next line exists
+ *     false  next line does not exist
+ */
+bool tv_get_next_line(const unsigned char **buf);
+
+/*
+ * start to read lines
+ *
+ * [In] block
+ *          the index of block to read text
+ *
+ * [In] is_multi
+ *          true  read 2 blocks
+ *          false read 1 block
+ */
+void tv_read_start(int block, bool is_multi);
+
+/*
+ * end to read lines
+ *
+ * return
+ *     read text size
+ */
+int tv_read_end(void);
+
+/* seek to the head of the file */
+void tv_seek_top(void);
+
+#endif