src/viewer/hex.c

   1 /*
   2    Internal file viewer for the Midnight Commander
   3    Function for hex view
   4
   5    Copyright (C) 1994-2017
   6    Free Software Foundation, Inc.
   7
   8    Written by:
   9    Miguel de Icaza, 1994, 1995, 1998
  10    Janne Kukonlehto, 1994, 1995
  11    Jakub Jelinek, 1995
  12    Joseph M. Hinkle, 1996
  13    Norbert Warmuth, 1997
  14    Pavel Machek, 1998
  15    Roland Illig <roland.illig@gmx.de>, 2004, 2005
  16    Slava Zanko <slavazanko@google.com>, 2009, 2013
  17    Andrew Borodin <aborodin@vmail.ru>, 2009
  18    Ilia Maslakov <il.smind@gmail.com>, 2009
  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 3 of the License,
  25    or (at your option) any later version.
  26
  27    The Midnight Commander is distributed in the hope that it will be useful,
  28    but WITHOUT ANY WARRANTY; without even the implied warranty of
  29    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  30    GNU 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, see <http://www.gnu.org/licenses/>.
  34  */
  35
  36 #include <config.h>
  37
  38 #include <errno.h>
  39 #include <inttypes.h>           /* uintmax_t */
  40
  41 #include "lib/global.h"
  42 #include "lib/tty/tty.h"
  43 #include "lib/skin.h"
  44 #include "lib/vfs/vfs.h"
  45 #include "lib/lock.h"           /* lock_file() and unlock_file() */
  46 #include "lib/util.h"
  47 #include "lib/widget.h"
  48 #ifdef HAVE_CHARSET
  49 #include "lib/charsets.h"
  50 #endif
  51
  52 #include "internal.h"
  53
  54 /*** global variables ****************************************************************************/
  55
  56 /*** file scope macro definitions ****************************************************************/
  57
  58 /*** file scope type declarations ****************************************************************/
  59
  60 typedef enum
  61 {
  62     MARK_NORMAL,
  63     MARK_SELECTED,
  64     MARK_CURSOR,
  65     MARK_CHANGED
  66 } mark_t;
  67
  68 /*** file scope variables ************************************************************************/
  69
  70 static const char hex_char[] = "0123456789ABCDEF";
  71
  72 /*** file scope functions ************************************************************************/
  73 /* --------------------------------------------------------------------------------------------- */
  74
  75 /* --------------------------------------------------------------------------------------------- */
  76 /** Determine the state of the current byte.
  77  *
  78  * @param view viewer object
  79  * @param from offset
  80  * @param curr current node
  81  */
  82
  83 static mark_t
  84 mcview_hex_calculate_boldflag (WView * view, off_t from, struct hexedit_change_node *curr,
  85                                gboolean force_changed)
  86 {
  87     return (from == view->hex_cursor) ? MARK_CURSOR
  88         : ((curr != NULL && from == curr->offset) || force_changed) ? MARK_CHANGED
  89         : (view->search_start <= from && from < view->search_end) ? MARK_SELECTED : MARK_NORMAL;
  90 }
  91
  92 /* --------------------------------------------------------------------------------------------- */
  93 /*** public functions ****************************************************************************/
  94 /* --------------------------------------------------------------------------------------------- */
  95
  96 void
  97 mcview_display_hex (WView * view)
  98 {
  99     const screen_dimen top = view->data_area.top;
 100     const screen_dimen left = view->data_area.left;
 101     const screen_dimen height = view->data_area.height;
 102     const screen_dimen width = view->data_area.width;
 103     const int ngroups = view->bytes_per_line / 4;
 104     /* 8 characters are used for the file offset, and every hex group
 105      * takes 13 characters. Starting at width of 80 columns, the groups
 106      * are separated by an extra vertical line. Starting at width of 81,
 107      * there is an extra space before the text column. There is always a
 108      * mostly empty column on the right, to allow overflowing CJKs.
 109      */
 110     const screen_dimen text_start = 8 + 13 * ngroups +
 111         ((width < 80) ? 0 : (width == 80) ? (ngroups - 1) : (ngroups - 1 + 1));
 112
 113     int row;
 114     off_t from;
 115     mark_t boldflag_byte = MARK_NORMAL;
 116     mark_t boldflag_char = MARK_NORMAL;
 117     struct hexedit_change_node *curr = view->change_list;
 118 #ifdef HAVE_CHARSET
 119     int cont_bytes = 0;         /* number of continuation bytes remanining from current UTF-8 */
 120     gboolean cjk_right = FALSE; /* whether the second byte of a CJK is to be processed */
 121 #endif /* HAVE_CHARSET */
 122     gboolean utf8_changed = FALSE;      /* whether any of the bytes in the UTF-8 were changed */
 123
 124     char hex_buff[10];          /* A temporary buffer for sprintf and mvwaddstr */
 125
 126     mcview_display_clean (view);
 127
 128     /* Find the first displayable changed byte */
 129     /* In UTF-8 mode, go back by 1 or maybe 2 lines to handle continuation bytes properly. */
 130     from = view->dpy_start;
 131     row = 0;
 132 #ifdef HAVE_CHARSET
 133     if (view->utf8)
 134     {
 135         if (from >= view->bytes_per_line)
 136         {
 137             row--;
 138             from -= view->bytes_per_line;
 139         }
 140         if (view->bytes_per_line == 4 && from >= view->bytes_per_line)
 141         {
 142             row--;
 143             from -= view->bytes_per_line;
 144         }
 145     }
 146 #endif /* HAVE_CHARSET */
 147     while (curr && (curr->offset < from))
 148     {
 149         curr = curr->next;
 150     }
 151
 152     for (; mcview_get_byte (view, from, NULL) && row < (int) height; row++)
 153     {
 154         screen_dimen col = 0;
 155         size_t i;
 156         int bytes;              /* Number of bytes already printed on the line */
 157
 158         /* Print the hex offset */
 159         if (row >= 0)
 160         {
 161             g_snprintf (hex_buff, sizeof (hex_buff), "%08" PRIXMAX " ", (uintmax_t) from);
 162             widget_move (view, top + row, left);
 163             tty_setcolor (VIEW_BOLD_COLOR);
 164             for (i = 0; col < width && hex_buff[i] != '\0'; col++, i++)
 165                 tty_print_char (hex_buff[i]);
 166             tty_setcolor (VIEW_NORMAL_COLOR);
 167         }
 168
 169         for (bytes = 0; bytes < view->bytes_per_line; bytes++, from++)
 170         {
 171             int c;
 172 #ifdef HAVE_CHARSET
 173             int ch = 0;
 174
 175             if (view->utf8)
 176             {
 177                 struct hexedit_change_node *corr = curr;
 178
 179                 if (cont_bytes != 0)
 180                 {
 181                     /* UTF-8 continuation bytes, print a space (with proper attributes)... */
 182                     cont_bytes--;
 183                     ch = ' ';
 184                     if (cjk_right)
 185                     {
 186                         /* ... except when it'd wipe out the right half of a CJK, then print nothing */
 187                         cjk_right = FALSE;
 188                         ch = -1;
 189                     }
 190                 }
 191                 else
 192                 {
 193                     int j;
 194                     gchar utf8buf[UTF8_CHAR_LEN + 1];
 195                     int res;
 196                     int first_changed = -1;
 197
 198                     for (j = 0; j < UTF8_CHAR_LEN; j++)
 199                     {
 200                         if (mcview_get_byte (view, from + j, &res))
 201                             utf8buf[j] = res;
 202                         else
 203                         {
 204                             utf8buf[j] = '\0';
 205                             break;
 206                         }
 207                         if (curr != NULL && from + j == curr->offset)
 208                         {
 209                             utf8buf[j] = curr->value;
 210                             if (first_changed == -1)
 211                                 first_changed = j;
 212                         }
 213                         if (curr != NULL && from + j >= curr->offset)
 214                             curr = curr->next;
 215                     }
 216                     utf8buf[UTF8_CHAR_LEN] = '\0';
 217
 218                     /* Determine the state of the current multibyte char */
 219                     ch = g_utf8_get_char_validated (utf8buf, -1);
 220                     if (ch == -1 || ch == -2)
 221                     {
 222                         ch = '.';
 223                     }
 224                     else
 225                     {
 226                         gchar *next_ch;
 227
 228                         next_ch = g_utf8_next_char (utf8buf);
 229                         cont_bytes = next_ch - utf8buf - 1;
 230                         if (g_unichar_iswide (ch))
 231                             cjk_right = TRUE;
 232                     }
 233
 234                     utf8_changed = (first_changed >= 0 && first_changed <= cont_bytes);
 235                     curr = corr;
 236                 }
 237             }
 238 #endif /* HAVE_CHARSET */
 239
 240             /* For negative rows, the only thing we care about is overflowing
 241              * UTF-8 continuation bytes which were handled above. */
 242             if (row < 0)
 243             {
 244                 if (curr != NULL && from == curr->offset)
 245                     curr = curr->next;
 246                 continue;
 247             }
 248
 249             if (!mcview_get_byte (view, from, &c))
 250                 break;
 251
 252             /* Save the cursor position for mcview_place_cursor() */
 253             if (from == view->hex_cursor && !view->hexview_in_text)
 254             {
 255                 view->cursor_row = row;
 256                 view->cursor_col = col;
 257             }
 258
 259             /* Determine the state of the current byte */
 260             boldflag_byte = mcview_hex_calculate_boldflag (view, from, curr, FALSE);
 261             boldflag_char = mcview_hex_calculate_boldflag (view, from, curr, utf8_changed);
 262
 263             /* Determine the value of the current byte */
 264             if (curr != NULL && from == curr->offset)
 265             {
 266                 c = curr->value;
 267                 curr = curr->next;
 268             }
 269
 270             /* Select the color for the hex number */
 271             tty_setcolor (boldflag_byte == MARK_NORMAL ? VIEW_NORMAL_COLOR :
 272                           boldflag_byte == MARK_SELECTED ? VIEW_BOLD_COLOR :
 273                           boldflag_byte == MARK_CHANGED ? VIEW_UNDERLINED_COLOR :
 274                           /* boldflag_byte == MARK_CURSOR */
 275                           view->hexview_in_text ? VIEW_SELECTED_COLOR : VIEW_UNDERLINED_COLOR);
 276
 277             /* Print the hex number */
 278             widget_move (view, top + row, left + col);
 279             if (col < width)
 280             {
 281                 tty_print_char (hex_char[c / 16]);
 282                 col += 1;
 283             }
 284             if (col < width)
 285             {
 286                 tty_print_char (hex_char[c % 16]);
 287                 col += 1;
 288             }
 289
 290             /* Print the separator */
 291             tty_setcolor (VIEW_NORMAL_COLOR);
 292             if (bytes != view->bytes_per_line - 1)
 293             {
 294                 if (col < width)
 295                 {
 296                     tty_print_char (' ');
 297                     col += 1;
 298                 }
 299
 300                 /* After every four bytes, print a group separator */
 301                 if (bytes % 4 == 3)
 302                 {
 303                     if (view->data_area.width >= 80 && col < width)
 304                     {
 305                         tty_print_one_vline (TRUE);
 306                         col += 1;
 307                     }
 308                     if (col < width)
 309                     {
 310                         tty_print_char (' ');
 311                         col += 1;
 312                     }
 313                 }
 314             }
 315
 316             /* Select the color for the character; this differs from the
 317              * hex color when boldflag == MARK_CURSOR */
 318             tty_setcolor (boldflag_char == MARK_NORMAL ? VIEW_NORMAL_COLOR :
 319                           boldflag_char == MARK_SELECTED ? VIEW_BOLD_COLOR :
 320                           boldflag_char == MARK_CHANGED ? VIEW_UNDERLINED_COLOR :
 321                           /* boldflag_char == MARK_CURSOR */
 322                           view->hexview_in_text ? VIEW_SELECTED_COLOR : MARKED_SELECTED_COLOR);
 323
 324
 325 #ifdef HAVE_CHARSET
 326             if (mc_global.utf8_display)
 327             {
 328                 if (!view->utf8)
 329                 {
 330                     c = convert_from_8bit_to_utf_c ((unsigned char) c, view->converter);
 331                 }
 332                 if (!g_unichar_isprint (c))
 333                     c = '.';
 334             }
 335             else if (view->utf8)
 336                 ch = convert_from_utf_to_current_c (ch, view->converter);
 337             else
 338 #endif
 339             {
 340 #ifdef HAVE_CHARSET
 341                 c = convert_to_display_c (c);
 342 #endif
 343
 344                 if (!is_printable (c))
 345                     c = '.';
 346             }
 347
 348             /* Print corresponding character on the text side */
 349             if (text_start + bytes < width)
 350             {
 351                 widget_move (view, top + row, left + text_start + bytes);
 352 #ifdef HAVE_CHARSET
 353                 if (view->utf8)
 354                     tty_print_anychar (ch);
 355                 else
 356 #endif
 357                     tty_print_char (c);
 358             }
 359
 360             /* Save the cursor position for mcview_place_cursor() */
 361             if (from == view->hex_cursor && view->hexview_in_text)
 362             {
 363                 view->cursor_row = row;
 364                 view->cursor_col = text_start + bytes;
 365             }
 366         }
 367     }
 368
 369     /* Be polite to the other functions */
 370     tty_setcolor (VIEW_NORMAL_COLOR);
 371
 372     mcview_place_cursor (view);
 373     view->dpy_end = from;
 374 }
 375
 376 /* --------------------------------------------------------------------------------------------- */
 377
 378 gboolean
 379 mcview_hexedit_save_changes (WView * view)
 380 {
 381     int answer = 0;
 382
 383     if (view->change_list == NULL)
 384         return TRUE;
 385
 386     while (answer == 0)
 387     {
 388         int fp;
 389         char *text;
 390         struct hexedit_change_node *curr, *next;
 391
 392         g_assert (view->filename_vpath != NULL);
 393
 394         fp = mc_open (view->filename_vpath, O_WRONLY);
 395         if (fp != -1)
 396         {
 397             for (curr = view->change_list; curr != NULL; curr = next)
 398             {
 399                 next = curr->next;
 400
 401                 if (mc_lseek (fp, curr->offset, SEEK_SET) == -1
 402                     || mc_write (fp, &(curr->value), 1) != 1)
 403                     goto save_error;
 404
 405                 /* delete the saved item from the change list */
 406                 view->change_list = next;
 407                 view->dirty++;
 408                 mcview_set_byte (view, curr->offset, curr->value);
 409                 g_free (curr);
 410             }
 411
 412             view->change_list = NULL;
 413
 414             if (view->locked)
 415                 view->locked = unlock_file (view->filename_vpath);
 416
 417             if (mc_close (fp) == -1)
 418                 message (D_ERROR, _("Save file"),
 419                          _("Error while closing the file:\n%s\n"
 420                            "Data may have been written or not"), unix_error_string (errno));
 421
 422             view->dirty++;
 423             return TRUE;
 424         }
 425
 426       save_error:
 427         text = g_strdup_printf (_("Cannot save file:\n%s"), unix_error_string (errno));
 428         (void) mc_close (fp);
 429
 430         answer = query_dialog (_("Save file"), text, D_ERROR, 2, _("&Retry"), _("&Cancel"));
 431         g_free (text);
 432     }
 433
 434     return FALSE;
 435 }
 436
 437 /* --------------------------------------------------------------------------------------------- */
 438
 439 void
 440 mcview_toggle_hexedit_mode (WView * view)
 441 {
 442     view->hexedit_mode = !view->hexedit_mode;
 443     view->dpy_bbar_dirty = TRUE;
 444     view->dirty++;
 445 }
 446
 447 /* --------------------------------------------------------------------------------------------- */
 448
 449 void
 450 mcview_hexedit_free_change_list (WView * view)
 451 {
 452     struct hexedit_change_node *curr, *next;
 453
 454     for (curr = view->change_list; curr != NULL; curr = next)
 455     {
 456         next = curr->next;
 457         g_free (curr);
 458     }
 459     view->change_list = NULL;
 460
 461     if (view->locked)
 462         view->locked = unlock_file (view->filename_vpath);
 463
 464     view->dirty++;
 465 }
 466
 467 /* --------------------------------------------------------------------------------------------- */
 468
 469 void
 470 mcview_enqueue_change (struct hexedit_change_node **head, struct hexedit_change_node *node)
 471 {
 472     /* chnode always either points to the head of the list or
 473      * to one of the ->next fields in the list. The value at
 474      * this location will be overwritten with the new node.   */
 475     struct hexedit_change_node **chnode = head;
 476
 477     while (*chnode != NULL && (*chnode)->offset < node->offset)
 478         chnode = &((*chnode)->next);
 479
 480     node->next = *chnode;
 481     *chnode = node;
 482 }
 483
 484 /* --------------------------------------------------------------------------------------------- */