src/editor/editdraw.c

   1 /*
   2    Editor text drawing.
   3
   4    Copyright (C) 1996, 1997, 1998, 2001, 2002, 2003, 2004, 2005, 2006,
   5    2007, 2011
   6    The Free Software Foundation, Inc.
   7
   8    Written by:
   9    Paul Sheer, 1996, 1997
  10
  11    This file is part of the Midnight Commander.
  12
  13    The Midnight Commander is free software: you can redistribute it
  14    and/or modify it under the terms of the GNU General Public License as
  15    published by the Free Software Foundation, either version 3 of the License,
  16    or (at your option) any later version.
  17
  18    The Midnight Commander is distributed in the hope that it will be useful,
  19    but WITHOUT ANY WARRANTY; without even the implied warranty of
  20    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  21    GNU General Public License for more details.
  22
  23    You should have received a copy of the GNU General Public License
  24    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  25  */
  26
  27 /** \file
  28  *  \brief Source: editor text drawing
  29  *  \author Paul Sheer
  30  *  \date 1996, 1997
  31  */
  32
  33 #include <config.h>
  34 #include <stdlib.h>
  35 #include <stdio.h>
  36 #include <stdarg.h>
  37 #include <sys/types.h>
  38 #include <unistd.h>
  39 #include <string.h>
  40 #include <ctype.h>
  41 #include <errno.h>
  42 #include <sys/stat.h>
  43
  44 #include "lib/global.h"
  45 #include "lib/tty/tty.h"        /* tty_printf() */
  46 #include "lib/tty/key.h"        /* is_idle() */
  47 #include "lib/skin.h"
  48 #include "lib/strutil.h"        /* utf string functions */
  49 #include "lib/util.h"           /* is_printable() */
  50 #include "lib/widget.h"         /* buttonbar_redraw() */
  51 #ifdef HAVE_CHARSET
  52 #include "lib/charsets.h"
  53 #endif
  54
  55 #include "src/setup.h"          /* edit_tab_spacing */
  56 #include "src/main.h"           /* macro_index */
  57
  58 #include "edit-impl.h"
  59 #include "editwidget.h"
  60
  61 /*** global variables ****************************************************************************/
  62
  63 /* Toggles statusbar draw style */
  64 int simple_statusbar = 0;
  65
  66 int visible_tabs = 1, visible_tws = 1;
  67
  68 /*** file scope macro definitions ****************************************************************/
  69
  70 #define MAX_LINE_LEN 1024
  71
  72 /* Text styles */
  73 #define MOD_ABNORMAL            (1 << 8)
  74 #define MOD_BOLD                (1 << 9)
  75 #define MOD_MARKED              (1 << 10)
  76 #define MOD_CURSOR              (1 << 11)
  77 #define MOD_WHITESPACE          (1 << 12)
  78
  79 #define edit_move(x,y) widget_move(edit, y, x);
  80
  81 #define key_pending(x) (!is_idle())
  82
  83 #define EDITOR_MINIMUM_TERMINAL_WIDTH 30
  84
  85 /*** file scope type declarations ****************************************************************/
  86
  87 struct line_s
  88 {
  89     unsigned int ch;
  90     unsigned int style;
  91 };
  92
  93 /*** file scope variables ************************************************************************/
  94
  95 /*** file scope functions ************************************************************************/
  96 /* --------------------------------------------------------------------------------------------- */
  97
  98 static inline void
  99 status_string (WEdit * edit, char *s, int w)
 100 {
 101     char byte_str[16];
 102     unsigned char cur_byte = 0;
 103     unsigned int cur_utf = 0;
 104     int cw = 1;
 105
 106     /*
 107      * If we are at the end of file, print <EOF>,
 108      * otherwise print the current character as is (if printable),
 109      * as decimal and as hex.
 110      */
 111     if (edit->curs1 < edit->last_byte)
 112     {
 113         if (!edit->utf8)
 114         {
 115             cur_byte = edit_get_byte (edit, edit->curs1);
 116
 117             g_snprintf (byte_str, sizeof (byte_str), "%4d 0x%03X",
 118                         (int) cur_byte, (unsigned) cur_byte);
 119         }
 120         else
 121         {
 122             cur_utf = edit_get_utf (edit, edit->curs1, &cw);
 123             if (cw > 0)
 124             {
 125                 g_snprintf (byte_str, sizeof (byte_str), "%04d 0x%03X",
 126                             (unsigned) cur_utf, (unsigned) cur_utf);
 127             }
 128             else
 129             {
 130                 cur_utf = edit_get_byte (edit, edit->curs1);
 131                 g_snprintf (byte_str, sizeof (byte_str), "%04d 0x%03X",
 132                             (int) cur_utf, (unsigned) cur_utf);
 133             }
 134
 135         }
 136     }
 137     else
 138     {
 139         strcpy (byte_str, "<EOF>     ");
 140     }
 141
 142     /* The field lengths just prevent the status line from shortening too much */
 143     if (simple_statusbar)
 144         g_snprintf (s, w,
 145                     "%c%c%c%c %3ld %5ld/%ld %6ld/%ld %s %s",
 146                     edit->mark1 != edit->mark2 ? (edit->column_highlight ? 'C' : 'B') : '-',
 147                     edit->modified ? 'M' : '-',
 148                     macro_index < 0 ? '-' : 'R',
 149                     edit->overwrite == 0 ? '-' : 'O',
 150                     edit->curs_col + edit->over_col,
 151                     edit->curs_line + 1,
 152                     edit->total_lines + 1, edit->curs1, edit->last_byte, byte_str,
 153 #ifdef HAVE_CHARSET
 154                     mc_global.source_codepage >=
 155                     0 ? get_codepage_id (mc_global.source_codepage) : ""
 156 #else
 157                     ""
 158 #endif
 159             );
 160     else
 161         g_snprintf (s, w,
 162                     "[%c%c%c%c] %2ld L:[%3ld+%2ld %3ld/%3ld] *(%-4ld/%4ldb) %s  %s",
 163                     edit->mark1 != edit->mark2 ? (edit->column_highlight ? 'C' : 'B') : '-',
 164                     edit->modified ? 'M' : '-',
 165                     macro_index < 0 ? '-' : 'R',
 166                     edit->overwrite == 0 ? '-' : 'O',
 167                     edit->curs_col + edit->over_col,
 168                     edit->start_line + 1,
 169                     edit->curs_row,
 170                     edit->curs_line + 1,
 171                     edit->total_lines + 1, edit->curs1, edit->last_byte, byte_str,
 172 #ifdef HAVE_CHARSET
 173                     mc_global.source_codepage >=
 174                     0 ? get_codepage_id (mc_global.source_codepage) : ""
 175 #else
 176                     ""
 177 #endif
 178             );
 179 }
 180
 181 /* --------------------------------------------------------------------------------------------- */
 182
 183 static inline void
 184 printwstr (const char *s, int len)
 185 {
 186     if (len > 0)
 187         tty_printf ("%-*.*s", len, len, s);
 188 }
 189
 190 /* --------------------------------------------------------------------------------------------- */
 191
 192 static inline void
 193 print_to_widget (WEdit * edit, long row, int start_col, int start_col_real,
 194                  long end_col, struct line_s line[], char *status, int bookmarked)
 195 {
 196     struct line_s *p;
 197
 198     int x = start_col_real;
 199     int x1 = start_col + EDIT_TEXT_HORIZONTAL_OFFSET + option_line_state_width;
 200     int y = row + EDIT_TEXT_VERTICAL_OFFSET;
 201     int cols_to_skip = abs (x);
 202     int i;
 203     int wrap_start;
 204     int len;
 205
 206     tty_setcolor (EDITOR_NORMAL_COLOR);
 207     if (bookmarked != 0)
 208         tty_setcolor (bookmarked);
 209
 210     len = end_col + 1 - start_col;
 211     wrap_start = option_word_wrap_line_length + edit->start_col;
 212
 213     if (len > 0 && edit->widget.y + y >= 0)
 214     {
 215         if (!show_right_margin || wrap_start > end_col)
 216             tty_draw_hline (edit->widget.y + y, edit->widget.x + x1, ' ', len);
 217         else if (wrap_start < 0)
 218         {
 219             tty_setcolor (EDITOR_RIGHT_MARGIN_COLOR);
 220             tty_draw_hline (edit->widget.y + y, edit->widget.x + x1, ' ', len);
 221         }
 222         else
 223         {
 224             if (wrap_start > 0)
 225                 tty_draw_hline (edit->widget.y + y, edit->widget.x + x1, ' ', wrap_start);
 226
 227             len -= wrap_start;
 228             if (len > 0)
 229             {
 230                 tty_setcolor (EDITOR_RIGHT_MARGIN_COLOR);
 231                 tty_draw_hline (edit->widget.y + y, edit->widget.x + x1 + wrap_start, ' ', len);
 232             }
 233         }
 234     }
 235
 236     if (option_line_state)
 237     {
 238         tty_setcolor (LINE_STATE_COLOR);
 239         for (i = 0; i < LINE_STATE_WIDTH; i++)
 240         {
 241             edit_move (x1 + i - option_line_state_width, y);
 242             if (status[i] == '\0')
 243                 status[i] = ' ';
 244             tty_print_char (status[i]);
 245         }
 246     }
 247
 248     edit_move (x1, y);
 249     i = 1;
 250     for (p = line; p->ch != 0; p++)
 251     {
 252         int style;
 253         unsigned int textchar;
 254         int color;
 255
 256         if (cols_to_skip != 0)
 257         {
 258             cols_to_skip--;
 259             continue;
 260         }
 261
 262         style = p->style & 0xFF00;
 263         textchar = p->ch;
 264         color = p->style >> 16;
 265
 266         if (style & MOD_ABNORMAL)
 267         {
 268             /* Non-printable - use black background */
 269             color = 0;
 270         }
 271
 272         if (style & MOD_WHITESPACE)
 273         {
 274             if (style & MOD_MARKED)
 275             {
 276                 textchar = ' ';
 277                 tty_setcolor (EDITOR_MARKED_COLOR);
 278             }
 279             else
 280                 tty_setcolor (EDITOR_WHITESPACE_COLOR);
 281         }
 282         else if (style & MOD_BOLD)
 283             tty_setcolor (EDITOR_BOLD_COLOR);
 284         else if (style & MOD_MARKED)
 285             tty_setcolor (EDITOR_MARKED_COLOR);
 286         else
 287             tty_lowlevel_setcolor (color);
 288
 289         if (show_right_margin)
 290         {
 291             if (i > option_word_wrap_line_length + edit->start_col)
 292                 tty_setcolor (EDITOR_RIGHT_MARGIN_COLOR);
 293             i++;
 294         }
 295
 296         tty_print_anychar (textchar);
 297     }
 298 }
 299
 300 /* --------------------------------------------------------------------------------------------- */
 301 /** b is a pointer to the beginning of the line */
 302
 303 static void
 304 edit_draw_this_line (WEdit * edit, long b, long row, long start_col, long end_col)
 305 {
 306     struct line_s line[MAX_LINE_LEN];
 307     struct line_s *p = line;
 308
 309     long m1 = 0, m2 = 0, q, c1, c2;
 310     int col, start_col_real;
 311     unsigned int c;
 312     int color;
 313     int abn_style;
 314     int i;
 315     int utf8lag = 0;
 316     unsigned int cur_line = 0;
 317     int book_mark = 0;
 318     char line_stat[LINE_STATE_WIDTH + 1] = "\0";
 319
 320     if (row > edit->widget.lines - 1 - EDIT_TEXT_VERTICAL_OFFSET)
 321         return;
 322
 323     if (book_mark_query_color (edit, edit->start_line + row, BOOK_MARK_COLOR))
 324         book_mark = BOOK_MARK_COLOR;
 325     else if (book_mark_query_color (edit, edit->start_line + row, BOOK_MARK_FOUND_COLOR))
 326         book_mark = BOOK_MARK_FOUND_COLOR;
 327
 328     if (book_mark)
 329         abn_style = book_mark << 16;
 330     else
 331         abn_style = MOD_ABNORMAL;
 332
 333     end_col -= EDIT_TEXT_HORIZONTAL_OFFSET + option_line_state_width;
 334
 335     edit_get_syntax_color (edit, b - 1, &color);
 336     q = edit_move_forward3 (edit, b, start_col - edit->start_col, 0);
 337     start_col_real = (col = (int) edit_move_forward3 (edit, b, 0, q)) + edit->start_col;
 338
 339     if (option_line_state)
 340     {
 341         cur_line = edit->start_line + row;
 342         if (cur_line <= (unsigned int) edit->total_lines)
 343         {
 344             g_snprintf (line_stat, LINE_STATE_WIDTH + 1, "%7i ", cur_line + 1);
 345         }
 346         else
 347         {
 348             memset (line_stat, ' ', LINE_STATE_WIDTH);
 349             line_stat[LINE_STATE_WIDTH] = '\0';
 350         }
 351         if (book_mark_query_color (edit, cur_line, BOOK_MARK_COLOR))
 352         {
 353             g_snprintf (line_stat, 2, "*");
 354         }
 355     }
 356
 357     if (col + 16 > -edit->start_col)
 358     {
 359         eval_marks (edit, &m1, &m2);
 360
 361         if (row <= edit->total_lines - edit->start_line)
 362         {
 363             long tws = 0;
 364             if (tty_use_colors () && visible_tws)
 365             {
 366                 tws = edit_eol (edit, b);
 367                 while (tws > b && ((c = edit_get_byte (edit, tws - 1)) == ' ' || c == '\t'))
 368                     tws--;
 369             }
 370
 371             while (col <= end_col - edit->start_col)
 372             {
 373                 int cw = 1;
 374                 int tab_over = 0;
 375                 gboolean wide_width_char = FALSE;
 376                 gboolean control_char = FALSE;
 377
 378                 p->ch = 0;
 379                 p->style = 0;
 380                 if (q == edit->curs1)
 381                     p->style |= MOD_CURSOR;
 382                 if (q >= m1 && q < m2)
 383                 {
 384                     if (edit->column_highlight)
 385                     {
 386                         int x;
 387                         x = edit_move_forward3 (edit, b, 0, q);
 388                         c1 = min (edit->column1, edit->column2);
 389                         c2 = max (edit->column1, edit->column2);
 390                         if (x >= c1 && x < c2)
 391                             p->style |= MOD_MARKED;
 392                     }
 393                     else
 394                         p->style |= MOD_MARKED;
 395                 }
 396                 if (q == edit->bracket)
 397                     p->style |= MOD_BOLD;
 398                 if (q >= edit->found_start && q < edit->found_start + edit->found_len)
 399                     p->style |= MOD_BOLD;
 400
 401                 if (!edit->utf8)
 402                 {
 403                     c = edit_get_byte (edit, q);
 404                 }
 405                 else
 406                 {
 407                     c = edit_get_utf (edit, q, &cw);
 408                 }
 409                 /* we don't use bg for mc - fg contains both */
 410                 if (book_mark)
 411                 {
 412                     p->style |= book_mark << 16;
 413                 }
 414                 else
 415                 {
 416                     edit_get_syntax_color (edit, q, &color);
 417                     p->style |= color << 16;
 418                 }
 419                 switch (c)
 420                 {
 421                 case '\n':
 422                     col = (end_col + utf8lag) - edit->start_col + 1;    /* quit */
 423                     break;
 424                 case '\t':
 425                     i = TAB_SIZE - ((int) col % TAB_SIZE);
 426                     tab_over = (end_col - edit->start_col) - (col + i - 1);
 427                     if (tab_over < 0)
 428                         i += tab_over;
 429                     col += i;
 430                     if (tty_use_colors () &&
 431                         ((visible_tabs || (visible_tws && q >= tws)) && enable_show_tabs_tws))
 432                     {
 433                         if (p->style & MOD_MARKED)
 434                             c = p->style;
 435                         else if (book_mark)
 436                             c |= book_mark << 16;
 437                         else
 438                             c = p->style | MOD_WHITESPACE;
 439                         if (i > 2)
 440                         {
 441                             p->ch = '<';
 442                             p->style = c;
 443                             p++;
 444                             while (--i > 1)
 445                             {
 446                                 p->ch = '-';
 447                                 p->style = c;
 448                                 p++;
 449                             }
 450                             p->ch = '>';
 451                             p->style = c;
 452                             p++;
 453                         }
 454                         else if (i > 1)
 455                         {
 456                             p->ch = '<';
 457                             p->style = c;
 458                             p++;
 459                             p->ch = '>';
 460                             p->style = c;
 461                             p++;
 462                         }
 463                         else
 464                         {
 465                             p->ch = '>';
 466                             p->style = c;
 467                             p++;
 468                         }
 469                     }
 470                     else if (tty_use_colors () && visible_tws && q >= tws && enable_show_tabs_tws)
 471                     {
 472                         p->ch = '.';
 473                         p->style |= MOD_WHITESPACE;
 474                         c = p->style & ~MOD_CURSOR;
 475                         p++;
 476                         while (--i)
 477                         {
 478                             p->ch = ' ';
 479                             p->style = c;
 480                             p++;
 481                         }
 482                     }
 483                     else
 484                     {
 485                         p->ch |= ' ';
 486                         c = p->style & ~MOD_CURSOR;
 487                         p++;
 488                         while (--i)
 489                         {
 490                             p->ch = ' ';
 491                             p->style = c;
 492                             p++;
 493                         }
 494                     }
 495                     break;
 496                 case ' ':
 497                     if (tty_use_colors () && visible_tws && q >= tws && enable_show_tabs_tws)
 498                     {
 499                         p->ch = '.';
 500                         p->style |= MOD_WHITESPACE;
 501                         p++;
 502                         col++;
 503                         break;
 504                     }
 505                     /* fallthrough */
 506                 default:
 507 #ifdef HAVE_CHARSET
 508                     if (mc_global.utf8_display)
 509                     {
 510                         if (!edit->utf8)
 511                         {
 512                             c = convert_from_8bit_to_utf_c ((unsigned char) c, edit->converter);
 513                         }
 514                         else
 515                         {
 516                             if (g_unichar_iswide (c))
 517                             {
 518                                 wide_width_char = TRUE;
 519                                 col++;
 520                             }
 521                         }
 522                     }
 523                     else if (edit->utf8)
 524                         c = convert_from_utf_to_current_c (c, edit->converter);
 525                     else
 526                         c = convert_to_display_c (c);
 527 #endif
 528
 529                     /* Caret notation for control characters */
 530                     if (c < 32)
 531                     {
 532                         p->ch = '^';
 533                         p->style = abn_style;
 534                         p++;
 535                         p->ch = c + 0x40;
 536                         p->style = abn_style;
 537                         p++;
 538                         col += 2;
 539                         control_char = TRUE;
 540                         break;
 541                     }
 542                     if (c == 127)
 543                     {
 544                         p->ch = '^';
 545                         p->style = abn_style;
 546                         p++;
 547                         p->ch = '?';
 548                         p->style = abn_style;
 549                         p++;
 550                         col += 2;
 551                         control_char = TRUE;
 552                         break;
 553                     }
 554                     if (!edit->utf8)
 555                     {
 556                         if ((mc_global.utf8_display && g_unichar_isprint (c)) ||
 557                             (!mc_global.utf8_display && is_printable (c)))
 558                         {
 559                             p->ch = c;
 560                             p++;
 561                         }
 562                         else
 563                         {
 564                             p->ch = '.';
 565                             p->style = abn_style;
 566                             p++;
 567                         }
 568                     }
 569                     else
 570                     {
 571                         if (g_unichar_isprint (c))
 572                         {
 573                             p->ch = c;
 574                             p++;
 575                         }
 576                         else
 577                         {
 578                             p->ch = '.';
 579                             p->style = abn_style;
 580                             p++;
 581                         }
 582                     }
 583                     col++;
 584                     break;
 585                 }               /* case */
 586
 587                 q++;
 588                 if (cw > 1)
 589                 {
 590                     q += cw - 1;
 591                 }
 592
 593                 if (col > (end_col - edit->start_col + 1))
 594                 {
 595                     if (wide_width_char)
 596                     {
 597                         p--;
 598                         break;
 599                     }
 600                     if (control_char)
 601                     {
 602                         p -= 2;
 603                         break;
 604                     }
 605                 }
 606             }
 607         }
 608     }
 609     else
 610     {
 611         start_col_real = start_col = 0;
 612     }
 613
 614     p->ch = 0;
 615
 616     print_to_widget (edit, row, start_col, start_col_real, end_col, line, line_stat, book_mark);
 617 }
 618
 619 /* --------------------------------------------------------------------------------------------- */
 620
 621 static inline void
 622 edit_draw_this_char (WEdit * edit, long curs, long row, long start_column, long end_column)
 623 {
 624     int b = edit_bol (edit, curs);
 625     edit_draw_this_line (edit, b, row, start_column, end_column);
 626 }
 627
 628 /* --------------------------------------------------------------------------------------------- */
 629 /** cursor must be in screen for other than REDRAW_PAGE passed in force */
 630
 631 static inline void
 632 render_edit_text (WEdit * edit, long start_row, long start_column, long end_row, long end_column)
 633 {
 634     static long prev_curs_row = 0;
 635     static long prev_curs = 0;
 636
 637     Widget *w = (Widget *) edit;
 638     Dlg_head *h = w->owner;
 639
 640     long row = 0, curs_row;
 641     int force = edit->force;
 642     long b;
 643     int y1, x1, y2, x2;
 644
 645     int last_line;
 646     int last_column;
 647
 648     /* draw only visible region */
 649
 650     last_line = h->y + h->lines - 1;
 651
 652     y1 = w->y;
 653     if (y1 > last_line - 1 /* buttonbar */ )
 654         return;
 655
 656     last_column = h->x + h->cols - 1;
 657
 658     x1 = w->x;
 659     if (x1 > last_column)
 660         return;
 661
 662     y2 = w->y + w->lines - 1;
 663     if (y2 < h->y + 1 /* menubar */ )
 664         return;
 665
 666     x2 = w->x + w->cols - 1;
 667     if (x2 < h->x)
 668         return;
 669
 670     if ((force & REDRAW_IN_BOUNDS) == 0)
 671     {
 672         /* !REDRAW_IN_BOUNDS means to ignore bounds and redraw whole rows */
 673         /* draw only visible region */
 674
 675         if (y2 <= last_line - 1 /* buttonbar */ )
 676             end_row = w->lines - 1;
 677         else if (y1 >= h->y + 1 /* menubar */ )
 678             end_row = h->lines - 1 - y1 - 1;
 679         else
 680             end_row = start_row + h->lines - 1 - 1;
 681
 682         if (x2 <= last_column)
 683             end_column = w->cols - 1;
 684         else if (x1 >= h->x)
 685             end_column = h->cols - 1 - x1;
 686         else
 687             end_column = start_column + h->cols - 1;
 688     }
 689
 690     /*
 691      * If the position of the page has not moved then we can draw the cursor
 692      * character only.  This will prevent line flicker when using arrow keys.
 693      */
 694     if ((force & REDRAW_CHAR_ONLY) == 0 || (force & REDRAW_PAGE) != 0)
 695     {
 696         if ((force & REDRAW_PAGE) != 0)
 697         {
 698             row = start_row;
 699             b = edit_move_forward (edit, edit->start_display, start_row, 0);
 700             while (row <= end_row)
 701             {
 702                 if (key_pending (edit))
 703                     return;
 704                 edit_draw_this_line (edit, b, row, start_column, end_column);
 705                 b = edit_move_forward (edit, b, 1, 0);
 706                 row++;
 707             }
 708         }
 709         else
 710         {
 711             curs_row = edit->curs_row;
 712
 713             if ((force & REDRAW_BEFORE_CURSOR) != 0 && start_row < curs_row)
 714             {
 715                 long upto = curs_row - 1 <= end_row ? curs_row - 1 : end_row;
 716
 717                 row = start_row;
 718                 b = edit->start_display;
 719                 while (row <= upto)
 720                 {
 721                     if (key_pending (edit))
 722                         return;
 723                     edit_draw_this_line (edit, b, row, start_column, end_column);
 724                     b = edit_move_forward (edit, b, 1, 0);
 725                 }
 726             }
 727
 728             /*          if (force & REDRAW_LINE)          ---> default */
 729             b = edit_bol (edit, edit->curs1);
 730             if (curs_row >= start_row && curs_row <= end_row)
 731             {
 732                 if (key_pending (edit))
 733                     return;
 734                 edit_draw_this_line (edit, b, curs_row, start_column, end_column);
 735             }
 736
 737             if ((force & REDRAW_AFTER_CURSOR) != 0 && end_row > curs_row)
 738             {
 739                 row = curs_row + 1 < start_row ? start_row : curs_row + 1;
 740                 b = edit_move_forward (edit, b, 1, 0);
 741                 while (row <= end_row)
 742                 {
 743                     if (key_pending (edit))
 744                         return;
 745                     edit_draw_this_line (edit, b, row, start_column, end_column);
 746                     b = edit_move_forward (edit, b, 1, 0);
 747                     row++;
 748                 }
 749             }
 750
 751             if ((force & REDRAW_LINE_ABOVE) != 0 && curs_row >= 1)
 752             {
 753                 row = curs_row - 1;
 754                 b = edit_move_backward (edit, edit_bol (edit, edit->curs1), 1);
 755                 if (row >= start_row && row <= end_row)
 756                 {
 757                     if (key_pending (edit))
 758                         return;
 759                     edit_draw_this_line (edit, b, row, start_column, end_column);
 760                 }
 761             }
 762
 763             if ((force & REDRAW_LINE_BELOW) != 0 && row < edit->widget.lines - 1)
 764             {
 765                 row = curs_row + 1;
 766                 b = edit_bol (edit, edit->curs1);
 767                 b = edit_move_forward (edit, b, 1, 0);
 768                 if (row >= start_row && row <= end_row)
 769                 {
 770                     if (key_pending (edit))
 771                         return;
 772                     edit_draw_this_line (edit, b, row, start_column, end_column);
 773                 }
 774             }
 775         }
 776     }
 777     else if (prev_curs_row < edit->curs_row)
 778     {
 779         /* with the new text highlighting, we must draw from the top down */
 780         edit_draw_this_char (edit, prev_curs, prev_curs_row, start_column, end_column);
 781         edit_draw_this_char (edit, edit->curs1, edit->curs_row, start_column, end_column);
 782     }
 783     else
 784     {
 785         edit_draw_this_char (edit, edit->curs1, edit->curs_row, start_column, end_column);
 786         edit_draw_this_char (edit, prev_curs, prev_curs_row, start_column, end_column);
 787     }
 788
 789     edit->force = 0;
 790
 791     prev_curs_row = edit->curs_row;
 792     prev_curs = edit->curs1;
 793 }
 794
 795 /* --------------------------------------------------------------------------------------------- */
 796
 797 static inline void
 798 edit_render (WEdit * edit, int page, int row_start, int col_start, int row_end, int col_end)
 799 {
 800     if (page)                   /* if it was an expose event, 'page' would be set */
 801         edit->force |= REDRAW_PAGE | REDRAW_IN_BOUNDS;
 802
 803     if (edit->force & REDRAW_COMPLETELY)
 804         buttonbar_redraw (find_buttonbar (edit->widget.owner));
 805     render_edit_text (edit, row_start, col_start, row_end, col_end);
 806     /*
 807      * edit->force != 0 means a key was pending and the redraw
 808      * was halted, so next time we must redraw everything in case stuff
 809      * was left undrawn from a previous key press.
 810      */
 811     if (edit->force)
 812         edit->force |= REDRAW_PAGE;
 813 }
 814
 815 /* --------------------------------------------------------------------------------------------- */
 816 /*** public functions ****************************************************************************/
 817 /* --------------------------------------------------------------------------------------------- */
 818
 819 /** Draw the status line at the top of the screen. The size of the filename
 820  * field varies depending on the width of the screen and the length of
 821  * the filename. */
 822 void
 823 edit_status (WEdit * edit)
 824 {
 825     const int w = edit->widget.owner->cols;
 826     const size_t status_size = w + 1;
 827     char *const status = g_malloc (status_size);
 828     int status_len;
 829     const char *fname = "";
 830     int fname_len;
 831     const int gap = 3;          /* between the filename and the status */
 832     const int right_gap = 5;    /* at the right end of the screen */
 833     const int preferred_fname_len = 16;
 834
 835     status_string (edit, status, status_size);
 836     status_len = (int) str_term_width1 (status);
 837
 838     if (edit->filename_vpath != NULL)
 839         fname = vfs_path_get_last_path_str (edit->filename_vpath);
 840
 841     fname_len = str_term_width1 (fname);
 842     if (fname_len < preferred_fname_len)
 843         fname_len = preferred_fname_len;
 844
 845     if (fname_len + gap + status_len + right_gap >= w)
 846     {
 847         if (preferred_fname_len + gap + status_len + right_gap >= w)
 848             fname_len = preferred_fname_len;
 849         else
 850             fname_len = w - (gap + status_len + right_gap);
 851         fname = str_trunc (fname, fname_len);
 852     }
 853
 854     dlg_move (edit->widget.owner, 0, 0);
 855     tty_setcolor (STATUSBAR_COLOR);
 856     printwstr (fname, fname_len + gap);
 857     printwstr (status, w - (fname_len + gap));
 858
 859     if (simple_statusbar && w > EDITOR_MINIMUM_TERMINAL_WIDTH)
 860     {
 861         size_t percent = 100;
 862
 863         if (edit->total_lines + 1 != 0)
 864             percent = (edit->curs_line + 1) * 100 / (edit->total_lines + 1);
 865         dlg_move (edit->widget.owner, 0, w - 5);
 866         tty_printf (" %3d%%", percent);
 867     }
 868
 869     g_free (status);
 870 }
 871
 872 /* --------------------------------------------------------------------------------------------- */
 873 /** this scrolls the text so that cursor is on the screen */
 874 void
 875 edit_scroll_screen_over_cursor (WEdit * edit)
 876 {
 877     long p;
 878     long outby;
 879     int b_extreme, t_extreme, l_extreme, r_extreme;
 880
 881     if (edit->widget.lines <= 0 || edit->widget.cols <= 0)
 882         return;
 883
 884     edit->widget.cols -= EDIT_TEXT_HORIZONTAL_OFFSET + option_line_state_width;
 885     edit->widget.lines -= EDIT_TEXT_VERTICAL_OFFSET;
 886
 887     r_extreme = EDIT_RIGHT_EXTREME;
 888     l_extreme = EDIT_LEFT_EXTREME;
 889     b_extreme = EDIT_BOTTOM_EXTREME;
 890     t_extreme = EDIT_TOP_EXTREME;
 891     if (edit->found_len)
 892     {
 893         b_extreme = max (edit->widget.lines / 4, b_extreme);
 894         t_extreme = max (edit->widget.lines / 4, t_extreme);
 895     }
 896     if (b_extreme + t_extreme + 1 > edit->widget.lines)
 897     {
 898         int n;
 899
 900         n = b_extreme + t_extreme;
 901         if (n == 0)
 902             n = 1;
 903         b_extreme = (b_extreme * (edit->widget.lines - 1)) / n;
 904         t_extreme = (t_extreme * (edit->widget.lines - 1)) / n;
 905     }
 906     if (l_extreme + r_extreme + 1 > edit->widget.cols)
 907     {
 908         int n;
 909
 910         n = l_extreme + t_extreme;
 911         if (n == 0)
 912             n = 1;
 913         l_extreme = (l_extreme * (edit->widget.cols - 1)) / n;
 914         r_extreme = (r_extreme * (edit->widget.cols - 1)) / n;
 915     }
 916     p = edit_get_col (edit) + edit->over_col;
 917     edit_update_curs_row (edit);
 918     outby = p + edit->start_col - edit->widget.cols + 1 + (r_extreme + edit->found_len);
 919     if (outby > 0)
 920         edit_scroll_right (edit, outby);
 921     outby = l_extreme - p - edit->start_col;
 922     if (outby > 0)
 923         edit_scroll_left (edit, outby);
 924     p = edit->curs_row;
 925     outby = p - edit->widget.lines + 1 + b_extreme;
 926     if (outby > 0)
 927         edit_scroll_downward (edit, outby);
 928     outby = t_extreme - p;
 929     if (outby > 0)
 930         edit_scroll_upward (edit, outby);
 931     edit_update_curs_row (edit);
 932
 933     edit->widget.lines += EDIT_TEXT_VERTICAL_OFFSET;
 934     edit->widget.cols += EDIT_TEXT_HORIZONTAL_OFFSET + option_line_state_width;
 935 }
 936
 937 /* --------------------------------------------------------------------------------------------- */
 938
 939 void
 940 edit_render_keypress (WEdit * edit)
 941 {
 942     edit_render (edit, 0, 0, 0, 0, 0);
 943 }
 944
 945 /* --------------------------------------------------------------------------------------------- */