src/viewer/move.c

   1 /*
   2    Internal file viewer for the Midnight Commander
   3    Functions for handle cursor movement
   4
   5    Copyright (C) 1994, 1995, 1996, 1998, 1999, 2000, 2001, 2002, 2003,
   6    2004, 2005, 2006, 2007, 2009 Free Software Foundation, Inc.
   7
   8    Written by: 1994, 1995, 1998 Miguel de Icaza
   9    1994, 1995 Janne Kukonlehto
  10    1995 Jakub Jelinek
  11    1996 Joseph M. Hinkle
  12    1997 Norbert Warmuth
  13    1998 Pavel Machek
  14    2004 Roland Illig <roland.illig@gmx.de>
  15    2005 Roland Illig <roland.illig@gmx.de>
  16    2009 Slava Zanko <slavazanko@google.com>
  17    2009 Andrew Borodin <aborodin@vmail.ru>
  18    2009, 2010 Ilia Maslakov <il.smind@gmail.com>
  19
  20    This file is part of the Midnight Commander.
  21
  22    The Midnight Commander is free software; you can redistribute it
  23    and/or modify it under the terms of the GNU General Public License as
  24    published by the Free Software Foundation; either version 2 of the
  25    License, or (at your option) any later version.
  26
  27    The Midnight Commander is distributed in the hope that it will be
  28    useful, but WITHOUT ANY WARRANTY; without even the implied warranty
  29    of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  30    General Public License for more details.
  31
  32    You should have received a copy of the GNU General Public License
  33    along with this program; if not, write to the Free Software
  34    Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
  35    MA 02110-1301, USA.
  36  */
  37
  38 /*
  39    The following variables have to do with the current position and are
  40    updated by the cursor movement functions.
  41
  42    In hex view and wrapped text view mode, dpy_start marks the offset of
  43    the top-left corner on the screen, in non-wrapping text mode it is
  44    the beginning of the current line.  In hex mode, hex_cursor is the
  45    offset of the cursor.  In non-wrapping text mode, dpy_text_column is
  46    the number of columns that are hidden on the left side on the screen.
  47
  48    In hex mode, dpy_start is updated by the view_fix_cursor_position()
  49    function in order to keep the other functions simple.  In
  50    non-wrapping text mode dpy_start and dpy_text_column are normalized
  51    such that dpy_text_column < view_get_datacolumns().
  52  */
  53
  54 #include <config.h>
  55
  56 #include "lib/global.h"
  57 #include "lib/tty/tty.h"
  58 #include "internal.h"
  59
  60 /*** global variables ****************************************************************************/
  61
  62 /*** file scope macro definitions ****************************************************************/
  63
  64 /*** file scope type declarations ****************************************************************/
  65
  66 /*** file scope variables ************************************************************************/
  67
  68 /*** file scope functions ************************************************************************/
  69
  70 static void
  71 mcview_movement_fixups (mcview_t * view, gboolean reset_search)
  72 {
  73     mcview_scroll_to_cursor (view);
  74     if (reset_search)
  75     {
  76         view->search_start = view->dpy_start;
  77         view->search_end = view->dpy_start;
  78     }
  79     view->dirty++;
  80 }
  81
  82 /* --------------------------------------------------------------------------------------------- */
  83
  84 /*** public functions ****************************************************************************/
  85
  86 /* --------------------------------------------------------------------------------------------- */
  87
  88 void
  89 mcview_move_up (mcview_t * view, off_t lines)
  90 {
  91     off_t new_offset;
  92     if (view->hex_mode)
  93     {
  94         off_t bytes = lines * view->bytes_per_line;
  95         if (view->hex_cursor >= bytes)
  96         {
  97             view->hex_cursor -= bytes;
  98             if (view->hex_cursor < view->dpy_start)
  99                 view->dpy_start = mcview_offset_doz (view->dpy_start, bytes);
 100         }
 101         else
 102         {
 103             view->hex_cursor %= view->bytes_per_line;
 104         }
 105     }
 106     else
 107     {
 108         off_t i;
 109         for (i = 0; i < lines; i++)
 110         {
 111             new_offset = mcview_bol (view, view->dpy_start);
 112             if (new_offset > 0)
 113                 new_offset--;
 114             new_offset = mcview_bol (view, new_offset);
 115             if (new_offset < 0)
 116                 new_offset = 0;
 117             view->dpy_start = new_offset;
 118         }
 119     }
 120     mcview_movement_fixups (view, TRUE);
 121 }
 122
 123 /* --------------------------------------------------------------------------------------------- */
 124
 125 void
 126 mcview_move_down (mcview_t * view, off_t lines)
 127 {
 128     off_t last_byte;
 129     last_byte = mcview_get_filesize (view);
 130     if (view->hex_mode)
 131     {
 132         off_t i, limit;
 133
 134         if (last_byte >= (off_t) view->bytes_per_line)
 135             limit = last_byte - view->bytes_per_line;
 136         else
 137             limit = 0;
 138         for (i = 0; i < lines && view->hex_cursor < limit; i++)
 139         {
 140             view->hex_cursor += view->bytes_per_line;
 141             if (lines != 1)
 142                 view->dpy_start += view->bytes_per_line;
 143         }
 144     }
 145     else
 146     {
 147         off_t i;
 148         for (i = 0; i < lines; i++)
 149         {
 150             off_t new_offset;
 151             new_offset = mcview_eol (view, view->dpy_start);
 152             view->dpy_start = new_offset;
 153         }
 154     }
 155     mcview_movement_fixups (view, TRUE);
 156 }
 157
 158 /* --------------------------------------------------------------------------------------------- */
 159
 160 void
 161 mcview_move_left (mcview_t * view, off_t columns)
 162 {
 163     if (view->hex_mode)
 164     {
 165         off_t old_cursor = view->hex_cursor;
 166         assert (columns == 1);
 167         if (view->hexview_in_text || !view->hexedit_lownibble)
 168         {
 169             if (view->hex_cursor > 0)
 170                 view->hex_cursor--;
 171         }
 172         if (!view->hexview_in_text)
 173             if (old_cursor > 0 || view->hexedit_lownibble)
 174                 view->hexedit_lownibble = !view->hexedit_lownibble;
 175     }
 176     else
 177     {
 178         if (view->dpy_text_column >= columns)
 179             view->dpy_text_column -= columns;
 180         else
 181             view->dpy_text_column = 0;
 182     }
 183     mcview_movement_fixups (view, FALSE);
 184 }
 185
 186 /* --------------------------------------------------------------------------------------------- */
 187
 188 void
 189 mcview_move_right (mcview_t * view, off_t columns)
 190 {
 191     if (view->hex_mode)
 192     {
 193         off_t last_byte;
 194         off_t old_cursor = view->hex_cursor;
 195         last_byte = mcview_offset_doz (mcview_get_filesize (view), 1);
 196         assert (columns == 1);
 197         if (view->hexview_in_text || view->hexedit_lownibble)
 198         {
 199             if (view->hex_cursor < last_byte)
 200                 view->hex_cursor++;
 201         }
 202         if (!view->hexview_in_text)
 203             if (old_cursor < last_byte || !view->hexedit_lownibble)
 204                 view->hexedit_lownibble = !view->hexedit_lownibble;
 205     }
 206     else
 207     {
 208         view->dpy_text_column += columns;
 209     }
 210     mcview_movement_fixups (view, FALSE);
 211 }
 212
 213 /* --------------------------------------------------------------------------------------------- */
 214
 215 void
 216 mcview_scroll_to_cursor (mcview_t * view)
 217 {
 218     if (view->hex_mode)
 219     {
 220         const off_t bytes = view->bytes_per_line;
 221         const off_t displaysize = view->data_area.height * bytes;
 222         const off_t cursor = view->hex_cursor;
 223         off_t topleft = view->dpy_start;
 224
 225         if (topleft + displaysize <= cursor)
 226             topleft = mcview_offset_rounddown (cursor, bytes) - (displaysize - bytes);
 227         if (cursor < topleft)
 228             topleft = mcview_offset_rounddown (cursor, bytes);
 229         view->dpy_start = topleft;
 230     }
 231 }
 232
 233 /* --------------------------------------------------------------------------------------------- */
 234
 235 void
 236 mcview_moveto_top (mcview_t * view)
 237 {
 238     view->dpy_start = 0;
 239     view->hex_cursor = 0;
 240     view->dpy_text_column = 0;
 241     mcview_movement_fixups (view, TRUE);
 242 }
 243
 244 /* --------------------------------------------------------------------------------------------- */
 245
 246 void
 247 mcview_moveto_bottom (mcview_t * view)
 248 {
 249     off_t datalines, lines_up, filesize, last_offset;
 250
 251     mcview_update_filesize (view);
 252
 253     if (view->growbuf_in_use)
 254         mcview_growbuf_read_until (view, OFFSETTYPE_MAX);
 255
 256     filesize = mcview_get_filesize (view);
 257     datalines = view->data_area.height;
 258     lines_up = mcview_offset_doz (datalines, 1);
 259
 260     if (view->hex_mode)
 261     {
 262         last_offset = mcview_offset_doz (filesize, 1);
 263         view->hex_cursor = filesize;
 264         mcview_move_up (view, lines_up);
 265         view->hex_cursor = last_offset;
 266     }
 267     else
 268     {
 269         view->dpy_start = filesize;
 270         mcview_move_up (view, 1);
 271     }
 272 }
 273
 274 /* --------------------------------------------------------------------------------------------- */
 275
 276 void
 277 mcview_moveto_bol (mcview_t * view)
 278 {
 279     if (view->hex_mode)
 280     {
 281         view->hex_cursor -= view->hex_cursor % view->bytes_per_line;
 282     }
 283     else if (!view->text_wrap_mode)
 284     {
 285         view->dpy_start = mcview_bol (view, view->dpy_start);
 286     }
 287     mcview_movement_fixups (view, TRUE);
 288 }
 289
 290 /* --------------------------------------------------------------------------------------------- */
 291
 292 void
 293 mcview_moveto_eol (mcview_t * view)
 294 {
 295     if (view->hex_mode)
 296     {
 297         off_t filesize, bol;
 298
 299         bol = mcview_offset_rounddown (view->hex_cursor, view->bytes_per_line);
 300         if (mcview_get_byte_indexed (view, bol, view->bytes_per_line - 1, NULL) == TRUE)
 301         {
 302             view->hex_cursor = bol + view->bytes_per_line - 1;
 303         }
 304         else
 305         {
 306             filesize = mcview_get_filesize (view);
 307             view->hex_cursor = mcview_offset_doz (filesize, 1);
 308         }
 309     }
 310     mcview_movement_fixups (view, FALSE);
 311 }
 312
 313 /* --------------------------------------------------------------------------------------------- */
 314
 315 void
 316 mcview_moveto_offset (mcview_t * view, off_t offset)
 317 {
 318     if (view->hex_mode)
 319     {
 320         view->hex_cursor = offset;
 321         view->dpy_start = offset - offset % view->bytes_per_line;
 322     }
 323     else
 324     {
 325         view->dpy_start = offset;
 326     }
 327     mcview_movement_fixups (view, TRUE);
 328 }
 329
 330 /* --------------------------------------------------------------------------------------------- */
 331
 332 void
 333 mcview_moveto (mcview_t * view, off_t line, off_t col)
 334 {
 335     off_t offset;
 336
 337     mcview_coord_to_offset (view, &offset, line, col);
 338     mcview_moveto_offset (view, offset);
 339 }
 340
 341 /* --------------------------------------------------------------------------------------------- */
 342
 343 void
 344 mcview_coord_to_offset (mcview_t * view, off_t * ret_offset, off_t line, off_t column)
 345 {
 346     coord_cache_entry_t coord;
 347
 348     coord.cc_line = line;
 349     coord.cc_column = column;
 350     coord.cc_nroff_column = column;
 351     mcview_ccache_lookup (view, &coord, CCACHE_OFFSET);
 352     *ret_offset = coord.cc_offset;
 353 }
 354
 355 /* --------------------------------------------------------------------------------------------- */
 356
 357 void
 358 mcview_offset_to_coord (mcview_t * view, off_t * ret_line, off_t * ret_column, off_t offset)
 359 {
 360     coord_cache_entry_t coord;
 361
 362     coord.cc_offset = offset;
 363     mcview_ccache_lookup (view, &coord, CCACHE_LINECOL);
 364
 365     *ret_line = coord.cc_line;
 366     *ret_column = (view->text_nroff_mode) ? coord.cc_nroff_column : coord.cc_column;
 367 }
 368
 369 /* --------------------------------------------------------------------------------------------- */
 370
 371 void
 372 mcview_place_cursor (mcview_t * view)
 373 {
 374     const screen_dimen top = view->data_area.top;
 375     const screen_dimen left = view->data_area.left;
 376     screen_dimen col = view->cursor_col;
 377     if (!view->hexview_in_text && view->hexedit_lownibble)
 378         col++;
 379     widget_move (&view->widget, top + view->cursor_row, left + col);
 380 }
 381
 382 /* --------------------------------------------------------------------------------------------- */
 383
 384 /* we have set view->search_start and view->search_end and must set
 385  * view->dpy_text_column and view->dpy_start
 386  * try to display maximum of match */
 387 void
 388 mcview_moveto_match (mcview_t * view)
 389 {
 390     off_t offset;
 391
 392     offset = view->search_start;
 393
 394     if (view->hex_mode)
 395     {
 396         view->hex_cursor = offset;
 397         view->dpy_start = offset - offset % view->bytes_per_line;
 398     }
 399     else
 400     {
 401         view->dpy_start = mcview_bol (view, offset);
 402     }
 403
 404     mcview_scroll_to_cursor (view);
 405     view->dirty++;
 406 }
 407
 408 /* --------------------------------------------------------------------------------------------- */