1 files changed, 415 insertions, 0 deletions

diff --git a/src/viewer/move.c b/src/viewer/move.c
new file mode 100644
index 0000000..4f15b7c
--- /dev/null
+++ b/src/viewer/move.c
@@ -0,0 +1,415 @@
+/*
+   Internal file viewer for the Midnight Commander
+   Functions for handle cursor movement
+
+   Copyright (C) 1994-2023
+   Free Software Foundation, Inc.
+
+   Written by:
+   Miguel de Icaza, 1994, 1995, 1998
+   Janne Kukonlehto, 1994, 1995
+   Jakub Jelinek, 1995
+   Joseph M. Hinkle, 1996
+   Norbert Warmuth, 1997
+   Pavel Machek, 1998
+   Roland Illig <roland.illig@gmx.de>, 2004, 2005
+   Slava Zanko <slavazanko@google.com>, 2009
+   Andrew Borodin <aborodin@vmail.ru>, 2009-2022
+   Ilia Maslakov <il.smind@gmail.com>, 2009, 2010
+
+   This file is part of the Midnight Commander.
+
+   The Midnight Commander 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 3 of the License,
+   or (at your option) any later version.
+
+   The Midnight Commander is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+/*
+   The following variables have to do with the current position and are
+   updated by the cursor movement functions.
+
+   In hex view and wrapped text view mode, dpy_start marks the offset of
+   the top-left corner on the screen, in non-wrapping text mode it is
+   the beginning of the current line.  In hex mode, hex_cursor is the
+   offset of the cursor.  In non-wrapping text mode, dpy_text_column is
+   the number of columns that are hidden on the left side on the screen.
+
+   In hex mode, dpy_start is updated by the view_fix_cursor_position()
+   function in order to keep the other functions simple.  In
+   non-wrapping text mode dpy_start and dpy_text_column are normalized
+   such that dpy_text_column < view_get_datacolumns().
+ */
+
+#include <config.h>
+
+#include "lib/global.h"
+#include "lib/tty/tty.h"
+#include "internal.h"
+
+/*** global variables ****************************************************************************/
+
+/*** file scope macro definitions ****************************************************************/
+
+/*** file scope type declarations ****************************************************************/
+
+/*** forward declarations (file scope functions) *************************************************/
+
+/*** file scope variables ************************************************************************/
+
+/* --------------------------------------------------------------------------------------------- */
+/*** file scope functions ************************************************************************/
+/* --------------------------------------------------------------------------------------------- */
+
+static void
+mcview_scroll_to_cursor (WView * view)
+{
+    if (view->mode_flags.hex)
+    {
+        off_t bytes = view->bytes_per_line;
+        off_t cursor = view->hex_cursor;
+        off_t topleft = view->dpy_start;
+        off_t displaysize;
+
+        displaysize = view->data_area.lines * bytes;
+        if (topleft + displaysize <= cursor)
+            topleft = mcview_offset_rounddown (cursor, bytes) - (displaysize - bytes);
+        if (cursor < topleft)
+            topleft = mcview_offset_rounddown (cursor, bytes);
+        view->dpy_start = topleft;
+        view->dpy_paragraph_skip_lines = 0;
+        view->dpy_wrap_dirty = TRUE;
+    }
+}
+
+/* --------------------------------------------------------------------------------------------- */
+
+static void
+mcview_movement_fixups (WView * view, gboolean reset_search)
+{
+    mcview_scroll_to_cursor (view);
+
+    if (reset_search)
+    {
+        view->search_start = view->mode_flags.hex ? view->hex_cursor : view->dpy_start;
+        view->search_end = view->search_start;
+    }
+
+    view->dirty++;
+}
+
+/* --------------------------------------------------------------------------------------------- */
+/*** public functions ****************************************************************************/
+/* --------------------------------------------------------------------------------------------- */
+
+void
+mcview_move_up (WView * view, off_t lines)
+{
+    if (!view->mode_flags.hex)
+        mcview_ascii_move_up (view, lines);
+    else
+    {
+        off_t bytes;
+
+        bytes = lines * view->bytes_per_line;
+
+        if (view->hex_cursor < bytes)
+            view->hex_cursor %= view->bytes_per_line;
+        else
+        {
+            view->hex_cursor -= bytes;
+            if (view->hex_cursor < view->dpy_start)
+            {
+                view->dpy_start = DOZ (view->dpy_start, bytes);
+                view->dpy_paragraph_skip_lines = 0;
+                view->dpy_wrap_dirty = TRUE;
+            }
+        }
+    }
+
+    mcview_movement_fixups (view, TRUE);
+}
+
+/* --------------------------------------------------------------------------------------------- */
+
+void
+mcview_move_down (WView * view, off_t lines)
+{
+    off_t last_byte;
+
+    last_byte = mcview_get_filesize (view);
+
+    if (!view->mode_flags.hex)
+        mcview_ascii_move_down (view, lines);
+    else
+    {
+        off_t i, limit;
+
+        limit = DOZ (last_byte, (off_t) view->bytes_per_line);
+
+        for (i = 0; i < lines && view->hex_cursor < limit; i++)
+        {
+            view->hex_cursor += view->bytes_per_line;
+
+            if (lines != 1)
+            {
+                view->dpy_start += view->bytes_per_line;
+                view->dpy_paragraph_skip_lines = 0;
+                view->dpy_wrap_dirty = TRUE;
+            }
+        }
+    }
+
+    mcview_movement_fixups (view, TRUE);
+}
+
+/* --------------------------------------------------------------------------------------------- */
+
+void
+mcview_move_left (WView * view, off_t columns)
+{
+    if (view->mode_flags.hex)
+    {
+        off_t old_cursor = view->hex_cursor;
+
+        g_assert (columns == 1);
+
+        if (view->hexview_in_text || !view->hexedit_lownibble)
+            if (view->hex_cursor > 0)
+                view->hex_cursor--;
+
+        if (!view->hexview_in_text)
+            if (old_cursor > 0 || view->hexedit_lownibble)
+                view->hexedit_lownibble = !view->hexedit_lownibble;
+    }
+    else if (!view->mode_flags.wrap)
+        view->dpy_text_column = DOZ (view->dpy_text_column, columns);
+
+    mcview_movement_fixups (view, FALSE);
+}
+
+/* --------------------------------------------------------------------------------------------- */
+
+void
+mcview_move_right (WView * view, off_t columns)
+{
+    if (view->mode_flags.hex)
+    {
+        off_t last_byte;
+        off_t old_cursor = view->hex_cursor;
+
+        last_byte = mcview_get_filesize (view);
+        last_byte = DOZ (last_byte, 1);
+
+        g_assert (columns == 1);
+
+        if (view->hexview_in_text || view->hexedit_lownibble)
+            if (view->hex_cursor < last_byte)
+                view->hex_cursor++;
+
+        if (!view->hexview_in_text)
+            if (old_cursor < last_byte || !view->hexedit_lownibble)
+                view->hexedit_lownibble = !view->hexedit_lownibble;
+    }
+    else if (!view->mode_flags.wrap)
+        view->dpy_text_column += columns;
+
+    mcview_movement_fixups (view, FALSE);
+}
+
+/* --------------------------------------------------------------------------------------------- */
+
+void
+mcview_moveto_top (WView * view)
+{
+    view->dpy_start = 0;
+    view->dpy_paragraph_skip_lines = 0;
+    mcview_state_machine_init (&view->dpy_state_top, 0);
+    view->hex_cursor = 0;
+    view->dpy_text_column = 0;
+    mcview_movement_fixups (view, TRUE);
+}
+
+/* --------------------------------------------------------------------------------------------- */
+
+void
+mcview_moveto_bottom (WView * view)
+{
+    off_t filesize;
+
+    mcview_update_filesize (view);
+
+    if (view->growbuf_in_use)
+        mcview_growbuf_read_all_data (view);
+
+    filesize = mcview_get_filesize (view);
+
+    if (view->mode_flags.hex)
+    {
+        view->hex_cursor = DOZ (filesize, 1);
+        mcview_movement_fixups (view, TRUE);
+    }
+    else
+    {
+        view->dpy_start = filesize;
+        view->dpy_paragraph_skip_lines = 0;
+        view->dpy_wrap_dirty = TRUE;
+        mcview_move_up (view, view->data_area.lines);
+    }
+}
+
+/* --------------------------------------------------------------------------------------------- */
+
+void
+mcview_moveto_bol (WView * view)
+{
+    if (!view->mode_flags.hex)
+        mcview_ascii_moveto_bol (view);
+    else
+    {
+        view->hex_cursor -= view->hex_cursor % view->bytes_per_line;
+        view->dpy_text_column = 0;
+    }
+
+    mcview_movement_fixups (view, TRUE);
+}
+
+/* --------------------------------------------------------------------------------------------- */
+
+void
+mcview_moveto_eol (WView * view)
+{
+    off_t bol;
+
+    if (!view->mode_flags.hex)
+        mcview_ascii_moveto_eol (view);
+    else
+    {
+        off_t filesize;
+
+        bol = mcview_offset_rounddown (view->hex_cursor, view->bytes_per_line);
+
+        if (mcview_get_byte_indexed (view, bol, view->bytes_per_line - 1, NULL))
+            view->hex_cursor = bol + view->bytes_per_line - 1;
+        else
+        {
+            filesize = mcview_get_filesize (view);
+            view->hex_cursor = DOZ (filesize, 1);
+        }
+    }
+
+    mcview_movement_fixups (view, FALSE);
+}
+
+/* --------------------------------------------------------------------------------------------- */
+
+void
+mcview_moveto_offset (WView * view, off_t offset)
+{
+    if (view->mode_flags.hex)
+    {
+        view->hex_cursor = offset;
+        view->dpy_start = offset - offset % view->bytes_per_line;
+        view->dpy_paragraph_skip_lines = 0;
+        view->dpy_wrap_dirty = TRUE;
+    }
+    else
+    {
+        view->dpy_start = offset;
+        view->dpy_paragraph_skip_lines = 0;
+        view->dpy_wrap_dirty = TRUE;
+    }
+
+    mcview_movement_fixups (view, TRUE);
+}
+
+/* --------------------------------------------------------------------------------------------- */
+
+void
+mcview_moveto (WView * view, off_t line, off_t col)
+{
+    off_t offset;
+
+    mcview_coord_to_offset (view, &offset, line, col);
+    mcview_moveto_offset (view, offset);
+}
+
+/* --------------------------------------------------------------------------------------------- */
+
+void
+mcview_coord_to_offset (WView * view, off_t * ret_offset, off_t line, off_t column)
+{
+    coord_cache_entry_t coord;
+
+    coord.cc_line = line;
+    coord.cc_column = column;
+    coord.cc_nroff_column = column;
+    mcview_ccache_lookup (view, &coord, CCACHE_OFFSET);
+    *ret_offset = coord.cc_offset;
+}
+
+/* --------------------------------------------------------------------------------------------- */
+
+void
+mcview_offset_to_coord (WView * view, off_t * ret_line, off_t * ret_column, off_t offset)
+{
+    coord_cache_entry_t coord;
+
+    coord.cc_offset = offset;
+    mcview_ccache_lookup (view, &coord, CCACHE_LINECOL);
+
+    *ret_line = coord.cc_line;
+    *ret_column = view->mode_flags.nroff ? coord.cc_nroff_column : coord.cc_column;
+}
+
+/* --------------------------------------------------------------------------------------------- */
+
+void
+mcview_place_cursor (WView * view)
+{
+    const WRect *r = &view->data_area;
+    int col = view->cursor_col;
+
+    if (!view->hexview_in_text && view->hexedit_lownibble)
+        col++;
+
+    widget_gotoyx (view, r->y + view->cursor_row, r->x + col);
+}
+
+/* --------------------------------------------------------------------------------------------- */
+/** we have set view->search_start and view->search_end and must set
+ * view->dpy_text_column and view->dpy_start
+ * try to display maximum of match */
+
+void
+mcview_moveto_match (WView * view)
+{
+    if (view->mode_flags.hex)
+    {
+        view->hex_cursor = view->search_start;
+        view->hexedit_lownibble = FALSE;
+        view->dpy_start = view->search_start - view->search_start % view->bytes_per_line;
+        view->dpy_end = view->search_end - view->search_end % view->bytes_per_line;
+        view->dpy_paragraph_skip_lines = 0;
+        view->dpy_wrap_dirty = TRUE;
+    }
+    else
+    {
+        view->dpy_start = mcview_bol (view, view->search_start, 0);
+        view->dpy_paragraph_skip_lines = 0;
+        view->dpy_wrap_dirty = TRUE;
+    }
+
+    mcview_scroll_to_cursor (view);
+    view->dirty++;
+}
+
+/* --------------------------------------------------------------------------------------------- */