src/editor/editdraw.c

   1 /* editor text drawing.
   2
   3    Copyright (C) 1996, 1997, 1998, 2001, 2002, 2003, 2004, 2005, 2006,
   4    2007 Free Software Foundation, Inc.
   5
   6    Authors: 1996, 1997 Paul Sheer
   7
   8    This program is free software; you can redistribute it and/or modify
   9    it under the terms of the GNU General Public License as published by
  10    the Free Software Foundation; either version 2 of the License, or
  11    (at your option) any later version.
  12
  13    This program is distributed in the hope that it will be useful,
  14    but WITHOUT ANY WARRANTY; without even the implied warranty of
  15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16    GNU General Public License for more details.
  17
  18    You should have received a copy of the GNU General Public License
  19    along with this program; if not, write to the Free Software
  20    Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  21    02110-1301, USA.
  22 */
  23
  24 /** \file
  25  *  \brief Source: editor text drawing
  26  *  \author Paul Sheer
  27  *  \date 1996, 1997
  28  */
  29
  30 #include <config.h>
  31 #include <stdlib.h>
  32 #include <stdio.h>
  33 #include <stdarg.h>
  34 #include <sys/types.h>
  35 #include <unistd.h>
  36 #include <string.h>
  37 #include <ctype.h>
  38 #include <errno.h>
  39 #include <sys/stat.h>
  40
  41 #include "lib/global.h"
  42 #include "lib/tty/tty.h"                /* tty_printf() */
  43 #include "lib/skin.h"
  44 #include "lib/tty/key.h"                /* is_idle() */
  45 #include "lib/strutil.h"                /* utf string functions */
  46
  47 #include "edit-impl.h"
  48 #include "edit-widget.h"
  49
  50 #define MAX_LINE_LEN 1024
  51
  52
  53 #include "src/widget.h"         /* buttonbar_redraw() */
  54 #include "src/charsets.h"
  55 #include "src/main.h"           /* source_codepage */
  56
  57 /* Text styles */
  58 #define MOD_ABNORMAL            (1 << 8)
  59 #define MOD_BOLD                (1 << 9)
  60 #define MOD_MARKED              (1 << 10)
  61 #define MOD_CURSOR              (1 << 11)
  62 #define MOD_WHITESPACE          (1 << 12)
  63
  64 #define FONT_OFFSET_X 0
  65 #define FONT_OFFSET_Y 0
  66 #define FIXED_FONT 1
  67 #define FONT_PIX_PER_LINE 1
  68 #define FONT_MEAN_WIDTH 1
  69
  70 /* Toggles statusbar draw style */
  71 int simple_statusbar = 0;
  72
  73 static inline void
  74 status_string (WEdit * edit, char *s, int w)
  75 {
  76     char byte_str[16];
  77     unsigned char cur_byte = 0;
  78     unsigned int cur_utf = 0;
  79     int cw = 1;
  80
  81     /*
  82      * If we are at the end of file, print <EOF>,
  83      * otherwise print the current character as is (if printable),
  84      * as decimal and as hex.
  85      */
  86     if (edit->curs1 < edit->last_byte) {
  87         if ( !edit->utf8 ) {
  88             cur_byte = edit_get_byte (edit, edit->curs1);
  89
  90             g_snprintf (byte_str, sizeof (byte_str), "%4d 0x%03X",
  91                         (int) cur_byte,
  92                         (unsigned) cur_byte);
  93         } else {
  94             cur_utf = edit_get_utf (edit, edit->curs1, &cw);
  95             if ( cw > 0 ) {
  96                 g_snprintf (byte_str, sizeof (byte_str), "%04d 0x%03X",
  97                             (unsigned) cur_utf,
  98                             (unsigned) cur_utf);
  99             } else {
 100                 cur_utf = edit_get_byte (edit, edit->curs1);
 101                 g_snprintf (byte_str, sizeof (byte_str), "%04d 0x%03X",
 102                             (int) cur_utf,
 103                             (unsigned) cur_utf);
 104             }
 105
 106         }
 107     } else {
 108         strcpy (byte_str, "<EOF>     ");
 109     }
 110
 111     /* The field lengths just prevent the status line from shortening too much */
 112     if (simple_statusbar)
 113         g_snprintf (s, w,
 114                         "%c%c%c%c %3ld %5ld/%ld %6ld/%ld %s %s",
 115                         edit->mark1 != edit->mark2 ? ( column_highlighting ? 'C' : 'B') : '-',
 116                         edit->modified ? 'M' : '-',
 117                         edit->macro_i < 0 ? '-' : 'R',
 118                         edit->overwrite == 0 ? '-' : 'O',
 119                         edit->curs_col + edit->over_col,
 120
 121                         edit->curs_line + 1,
 122                         edit->total_lines + 1,
 123
 124                         edit->curs1,
 125                         edit->last_byte,
 126                         byte_str,
 127
 128 #ifdef HAVE_CHARSET
 129                         source_codepage >= 0 ? get_codepage_id (source_codepage) : ""
 130 #else
 131                         ""
 132 #endif
 133                     );
 134     else
 135         g_snprintf (s, w,
 136                         "[%c%c%c%c] %2ld L:[%3ld+%2ld %3ld/%3ld] *(%-4ld/%4ldb) %s  %s",
 137                         edit->mark1 != edit->mark2 ? ( column_highlighting ? 'C' : 'B') : '-',
 138                         edit->modified ? 'M' : '-',
 139                         edit->macro_i < 0 ? '-' : 'R',
 140                         edit->overwrite == 0 ? '-' : 'O',
 141                         edit->curs_col + edit->over_col,
 142
 143                         edit->start_line + 1,
 144                         edit->curs_row,
 145                         edit->curs_line + 1,
 146                         edit->total_lines + 1,
 147
 148                         edit->curs1,
 149                         edit->last_byte,
 150                         byte_str,
 151
 152 #ifdef HAVE_CHARSET
 153                         source_codepage >= 0 ? get_codepage_id (source_codepage) : ""
 154 #else
 155                         ""
 156 #endif
 157                     );
 158 }
 159
 160 static inline void
 161 printwstr (const char *s, int len)
 162 {
 163     if (len > 0)
 164         tty_printf ("%-*.*s", len, len, s);
 165 }
 166
 167 /* Draw the status line at the top of the widget. The size of the filename
 168  * field varies depending on the width of the screen and the length of
 169  * the filename. */
 170 void
 171 edit_status (WEdit *edit)
 172 {
 173     const int w = edit->widget.cols;
 174     const size_t status_size = w + 1;
 175     char * const status = g_malloc (status_size);
 176     int status_len;
 177     const char *fname = "";
 178     int fname_len;
 179     const int gap = 3; /* between the filename and the status */
 180     const int right_gap = 5; /* at the right end of the screen */
 181     const int preferred_fname_len = 16;
 182
 183     status_string (edit, status, status_size);
 184     status_len = (int) str_term_width1 (status);
 185
 186     if (edit->filename)
 187         fname = edit->filename;
 188     fname_len = str_term_width1 (fname);
 189     if (fname_len < preferred_fname_len)
 190         fname_len = preferred_fname_len;
 191
 192     if (fname_len + gap + status_len + right_gap >= w) {
 193         if (preferred_fname_len + gap + status_len + right_gap >= w)
 194             fname_len = preferred_fname_len;
 195         else
 196             fname_len = w - (gap + status_len + right_gap);
 197         fname = str_trunc (fname, fname_len);
 198     }
 199
 200     widget_move (edit, 0, 0);
 201     tty_setcolor (SELECTED_COLOR);
 202     printwstr (fname, fname_len + gap);
 203     printwstr (status, w - (fname_len + gap));
 204
 205     if (simple_statusbar && edit->widget.cols > 30) {
 206         size_t percent;
 207         if (edit->total_lines + 1 != 0)
 208             percent = (edit->curs_line + 1) * 100 / (edit->total_lines + 1);
 209         else
 210             percent = 100;
 211         widget_move (edit, 0, edit->widget.cols - 5);
 212         tty_printf (" %3d%%", percent);
 213     }
 214     tty_setcolor (EDITOR_NORMAL_COLOR);
 215
 216     g_free (status);
 217 }
 218
 219 /* this scrolls the text so that cursor is on the screen */
 220 void edit_scroll_screen_over_cursor (WEdit * edit)
 221 {
 222     int p;
 223     int outby;
 224     int b_extreme, t_extreme, l_extreme, r_extreme;
 225
 226     if (edit->num_widget_lines <= 0 || edit->num_widget_columns <= 0)
 227         return;
 228
 229     edit->num_widget_columns -= EDIT_TEXT_HORIZONTAL_OFFSET + option_line_state_width;
 230     edit->num_widget_lines -= EDIT_TEXT_VERTICAL_OFFSET - 1;
 231
 232     r_extreme = EDIT_RIGHT_EXTREME;
 233     l_extreme = EDIT_LEFT_EXTREME;
 234     b_extreme = EDIT_BOTTOM_EXTREME;
 235     t_extreme = EDIT_TOP_EXTREME;
 236     if (edit->found_len) {
 237         b_extreme = max (edit->num_widget_lines / 4, b_extreme);
 238         t_extreme = max (edit->num_widget_lines / 4, t_extreme);
 239     }
 240     if (b_extreme + t_extreme + 1 > edit->num_widget_lines) {
 241         int n;
 242         n = b_extreme + t_extreme;
 243         b_extreme = (b_extreme * (edit->num_widget_lines - 1)) / n;
 244         t_extreme = (t_extreme * (edit->num_widget_lines - 1)) / n;
 245     }
 246     if (l_extreme + r_extreme + 1 > edit->num_widget_columns) {
 247         int n;
 248         n = l_extreme + t_extreme;
 249         l_extreme = (l_extreme * (edit->num_widget_columns - 1)) / n;
 250         r_extreme = (r_extreme * (edit->num_widget_columns - 1)) / n;
 251     }
 252     p = edit_get_col (edit) + edit->over_col;
 253     edit_update_curs_row (edit);
 254     outby = p + edit->start_col - edit->num_widget_columns + 1 + (r_extreme + edit->found_len);
 255     if (outby > 0)
 256         edit_scroll_right (edit, outby);
 257     outby = l_extreme - p - edit->start_col;
 258     if (outby > 0)
 259         edit_scroll_left (edit, outby);
 260     p = edit->curs_row;
 261     outby = p - edit->num_widget_lines + 1 + b_extreme;
 262     if (outby > 0)
 263         edit_scroll_downward (edit, outby);
 264     outby = t_extreme - p;
 265     if (outby > 0)
 266         edit_scroll_upward (edit, outby);
 267     edit_update_curs_row (edit);
 268
 269     edit->num_widget_lines += EDIT_TEXT_VERTICAL_OFFSET - 1;
 270     edit->num_widget_columns += EDIT_TEXT_HORIZONTAL_OFFSET + option_line_state_width;
 271 }
 272
 273 #define edit_move(x,y) widget_move(edit, y, x);
 274
 275 struct line_s {
 276     unsigned int ch;
 277     unsigned int style;
 278 };
 279
 280 static inline void
 281 print_to_widget (WEdit *edit, long row, int start_col, int start_col_real,
 282                  long end_col, struct line_s line[], char *status)
 283 {
 284     struct line_s *p;
 285
 286     int x = start_col_real;
 287     int x1 = start_col + EDIT_TEXT_HORIZONTAL_OFFSET + option_line_state_width;
 288     int y = row + EDIT_TEXT_VERTICAL_OFFSET;
 289     int cols_to_skip = abs (x);
 290     int i;
 291
 292     tty_setcolor (EDITOR_NORMAL_COLOR);
 293
 294     if (!show_right_margin) {
 295         tty_draw_hline (edit->widget.y + y, edit->widget.x + x1,
 296                        ' ', end_col + 1 - start_col);
 297     } else if (edit->start_col < option_word_wrap_line_length) {
 298         tty_draw_hline (edit->widget.y + y,
 299                         edit->widget.x + x1,
 300                         ' ',
 301                         option_word_wrap_line_length - edit->start_col);
 302
 303         tty_setcolor (EDITOR_RIGHT_MARGIN_COLOR);
 304         tty_draw_hline (edit->widget.y + y,
 305                         edit->widget.x + x1 + option_word_wrap_line_length + edit->start_col,
 306                         ' ',
 307                         end_col + 1 - start_col);
 308     }
 309
 310     if (option_line_state) {
 311         for (i = 0; i < LINE_STATE_WIDTH; i++)
 312             if (status[i] == '\0')
 313                 status[i] = ' ';
 314
 315         tty_setcolor (LINE_STATE_COLOR);
 316         edit_move (x1 + FONT_OFFSET_X - option_line_state_width, y + FONT_OFFSET_Y);
 317         tty_print_string (status);
 318     }
 319
 320     edit_move (x1 + FONT_OFFSET_X, y + FONT_OFFSET_Y);
 321     p = line;
 322     i = 1;
 323     while (p->ch) {
 324         int style;
 325         unsigned int textchar;
 326         int color;
 327
 328         if (cols_to_skip) {
 329             p++;
 330             cols_to_skip--;
 331             continue;
 332         }
 333
 334         style = p->style & 0xFF00;
 335         textchar = p->ch;
 336         color = p->style >> 16;
 337
 338         if (style & MOD_ABNORMAL) {
 339             /* Non-printable - use black background */
 340             color = 0;
 341         }
 342
 343         if (style & MOD_WHITESPACE) {
 344             if (style & MOD_MARKED) {
 345                 textchar = ' ';
 346                 tty_setcolor (EDITOR_MARKED_COLOR);
 347             } else {
 348 #if 0
 349                 if (color != EDITOR_NORMAL_COLOR) {
 350                     textchar = ' ';
 351                     tty_lowlevel_setcolor (color);
 352                 } else
 353 #endif
 354                     tty_setcolor (EDITOR_WHITESPACE_COLOR);
 355             }
 356         } else {
 357             if (style & MOD_BOLD) {
 358                 tty_setcolor (EDITOR_BOLD_COLOR);
 359             } else if (style & MOD_MARKED) {
 360                 tty_setcolor (EDITOR_MARKED_COLOR);
 361             } else {
 362                 tty_lowlevel_setcolor (color);
 363             }
 364         }
 365         if (show_right_margin) {
 366             if (i > option_word_wrap_line_length + edit->start_col)
 367                 tty_setcolor (EDITOR_RIGHT_MARGIN_COLOR);
 368             i++;
 369         }
 370         tty_print_anychar (textchar);
 371         p++;
 372     }
 373 }
 374
 375 int visible_tabs = 1, visible_tws = 1;
 376
 377 /* b is a pointer to the beginning of the line */
 378 static void
 379 edit_draw_this_line (WEdit *edit, long b, long row, long start_col,
 380                      long end_col)
 381 {
 382     struct line_s line[MAX_LINE_LEN];
 383     struct line_s *p = line;
 384
 385     long m1 = 0, m2 = 0, q, c1, c2;
 386     int col, start_col_real;
 387     unsigned int c;
 388     int color;
 389     int abn_style;
 390     int i;
 391     int utf8lag = 0;
 392     unsigned int cur_line = 0;
 393     int book_mark = 0;
 394     char line_stat[LINE_STATE_WIDTH + 1];
 395
 396     if (row > edit->num_widget_lines - EDIT_TEXT_VERTICAL_OFFSET) {
 397          return;
 398     }
 399     if (book_mark_query_color(edit, edit->start_line + row, BOOK_MARK_COLOR)) {
 400         book_mark = BOOK_MARK_COLOR;
 401     } else if (book_mark_query_color(edit, edit->start_line + row, BOOK_MARK_FOUND_COLOR)) {
 402         book_mark = BOOK_MARK_FOUND_COLOR;
 403     }
 404
 405     if (book_mark)
 406         abn_style = book_mark << 16;
 407     else
 408         abn_style = MOD_ABNORMAL;
 409
 410     end_col -= EDIT_TEXT_HORIZONTAL_OFFSET + option_line_state_width;
 411
 412     edit_get_syntax_color (edit, b - 1, &color);
 413     q = edit_move_forward3 (edit, b, start_col - edit->start_col, 0);
 414     start_col_real = (col =
 415                       (int) edit_move_forward3 (edit, b, 0,
 416                                                 q)) + edit->start_col;
 417     if ( option_line_state ) {
 418         cur_line = edit->start_line + row;
 419         if ( cur_line <= (unsigned int) edit->total_lines ) {
 420             g_snprintf (line_stat, LINE_STATE_WIDTH + 1, "%7i ", cur_line + 1);
 421         } else {
 422             memset(line_stat, ' ', LINE_STATE_WIDTH);
 423             line_stat[LINE_STATE_WIDTH] = '\0';
 424         }
 425         if (book_mark_query_color (edit, cur_line, BOOK_MARK_COLOR)){
 426             g_snprintf (line_stat, 2, "*");
 427         }
 428     }
 429
 430     if (col + 16 > -edit->start_col) {
 431         eval_marks (edit, &m1, &m2);
 432
 433         if (row <= edit->total_lines - edit->start_line) {
 434             long tws = 0;
 435             if (tty_use_colors () && visible_tws) {
 436                 tws = edit_eol (edit, b);
 437                 while (tws > b && ((c = edit_get_byte (edit, tws - 1)) == ' '
 438                                    || c == '\t'))
 439                     tws--;
 440             }
 441
 442             while (col <= end_col - edit->start_col) {
 443                 int cw = 1;
 444
 445                 p->ch = 0;
 446                 p->style = 0;
 447                 if (q == edit->curs1)
 448                     p->style |= MOD_CURSOR;
 449                 if (q >= m1 && q < m2) {
 450                     if (column_highlighting) {
 451                         int x;
 452                         x = edit_move_forward3 (edit, b, 0, q);
 453                         c1 = min (edit->column1, edit->column2);
 454                         c2 = max (edit->column1, edit->column2);
 455                         if (x >= c1 && x < c2)
 456                             p->style |= MOD_MARKED;
 457                     } else
 458                         p->style |= MOD_MARKED;
 459                 }
 460                 if (q == edit->bracket)
 461                     p->style |= MOD_BOLD;
 462                 if (q >= edit->found_start
 463                     && q < edit->found_start + edit->found_len)
 464                     p->style |= MOD_BOLD;
 465
 466                 if ( !edit->utf8 ) {
 467                     c = edit_get_byte (edit, q);
 468                 } else {
 469                     c = edit_get_utf (edit, q, &cw);
 470                 }
 471                 /* we don't use bg for mc - fg contains both */
 472                 if (book_mark) {
 473                     p->style |= book_mark << 16;
 474                 } else {
 475                     edit_get_syntax_color (edit, q, &color);
 476                     p->style |= color << 16;
 477                 }
 478                 switch (c) {
 479                 case '\n':
 480                     col = (end_col + utf8lag) - edit->start_col + 1;    /* quit */
 481                     break;
 482                 case '\t':
 483                     i = TAB_SIZE - ((int) col % TAB_SIZE);
 484                     col += i;
 485                     if (tty_use_colors() &&
 486                        ((visible_tabs || (visible_tws && q >= tws)) && enable_show_tabs_tws)) {
 487                         if (p->style & MOD_MARKED)
 488                             c = p->style;
 489                         else if (book_mark)
 490                             c |= book_mark << 16;
 491                         else
 492                             c = p->style | MOD_WHITESPACE;
 493                         if (i > 2) {
 494                             p->ch = '<';
 495                             p->style = c;
 496                             p++;
 497                             while (--i > 1) {
 498                                 p->ch = '-';
 499                                 p->style = c;
 500                                 p++;
 501                             }
 502                             p->ch = '>';
 503                             p->style = c;
 504                             p++;
 505                         } else if (i > 1) {
 506                             p->ch = '<';
 507                             p->style = c;
 508                             p++;
 509                             p->ch = '>';
 510                             p->style = c;
 511                             p++;
 512                         } else {
 513                             p->ch = '>';
 514                             p->style = c;
 515                             p++;
 516                         }
 517                     } else if (tty_use_colors() && visible_tws && q >= tws && enable_show_tabs_tws) {
 518                         p->ch = '.';
 519                         p->style |= MOD_WHITESPACE;
 520                         c = p->style & ~MOD_CURSOR;
 521                         p++;
 522                         while (--i) {
 523                             p->ch = ' ';
 524                             p->style = c;
 525                             p++;
 526                         }
 527                     } else {
 528                         p->ch |= ' ';
 529                         c = p->style & ~MOD_CURSOR;
 530                         p++;
 531                         while (--i) {
 532                             p->ch = ' ';
 533                             p->style = c;
 534                             p++;
 535                         }
 536                     }
 537                     break;
 538                 case ' ':
 539                     if (tty_use_colors() && visible_tws && q >= tws && enable_show_tabs_tws) {
 540                         p->ch = '.';
 541                         p->style |= MOD_WHITESPACE;
 542                         p++;
 543                         col++;
 544                         break;
 545                     }
 546                     /* fallthrough */
 547                 default:
 548 #ifdef HAVE_CHARSET
 549                     if ( utf8_display ) {
 550                         if ( !edit->utf8 ) {
 551                             c = convert_from_8bit_to_utf_c ((unsigned char) c, edit->converter);
 552                         }
 553                     } else if ( edit->utf8 )
 554                         c = convert_from_utf_to_current_c (c, edit->converter);
 555                     else
 556 #endif
 557                         c = convert_to_display_c (c);
 558
 559                     /* Caret notation for control characters */
 560                     if (c < 32) {
 561                         p->ch = '^';
 562                         p->style = abn_style;
 563                         p++;
 564                         p->ch = c + 0x40;
 565                         p->style = abn_style;
 566                         p++;
 567                         col += 2;
 568                         break;
 569                     }
 570                     if (c == 127) {
 571                         p->ch = '^';
 572                         p->style = abn_style;
 573                         p++;
 574                         p->ch = '?';
 575                         p->style = abn_style;
 576                         p++;
 577                         col += 2;
 578                         break;
 579                     }
 580                     if (!edit->utf8) {
 581                         if ( ( utf8_display && g_unichar_isprint (c) ) ||
 582                              ( !utf8_display && is_printable (c) ) ) {
 583                                 p->ch = c;
 584                                 p++;
 585                         } else {
 586                                 p->ch = '.';
 587                                 p->style = abn_style;
 588                                 p++;
 589                         }
 590                     } else {
 591                         if ( g_unichar_isprint (c) ) {
 592                             p->ch = c;
 593                             p++;
 594                         } else {
 595                             p->ch = '.';
 596                             p->style = abn_style;
 597                             p++;
 598                         }
 599                     }
 600                     col++;
 601                     break;
 602                 } /* case */
 603
 604                 q++;
 605                 if ( cw > 1) {
 606                   q += cw - 1;
 607                 }
 608             }
 609         }
 610     } else {
 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);
 617 }
 618
 619 #define key_pending(x) (!is_idle())
 620
 621 static inline void
 622 edit_draw_this_char (WEdit * edit, long curs, long row)
 623 {
 624     int b = edit_bol (edit, curs);
 625     edit_draw_this_line (edit, b, row, 0, edit->num_widget_columns - 1);
 626 }
 627
 628 /* cursor must be in screen for other than REDRAW_PAGE passed in force */
 629 static inline void
 630 render_edit_text (WEdit * edit, long start_row, long start_column, long end_row,
 631                   long end_column)
 632 {
 633     long row = 0, curs_row;
 634     static long prev_curs_row = 0;
 635     static long prev_curs = 0;
 636
 637     int force = edit->force;
 638     long b;
 639
 640 /*
 641  * If the position of the page has not moved then we can draw the cursor
 642  * character only.  This will prevent line flicker when using arrow keys.
 643  */
 644     if ((!(force & REDRAW_CHAR_ONLY)) || (force & REDRAW_PAGE)) {
 645         if (!(force & REDRAW_IN_BOUNDS)) {      /* !REDRAW_IN_BOUNDS means to ignore bounds and redraw whole rows */
 646             start_row = 0;
 647             end_row = edit->num_widget_lines - 1;
 648             start_column = 0;
 649             end_column = edit->num_widget_columns - 1;
 650         }
 651         if (force & REDRAW_PAGE) {
 652             row = start_row;
 653             b = edit_move_forward (edit, edit->start_display, start_row, 0);
 654             while (row <= end_row) {
 655                 if (key_pending (edit))
 656                     goto exit_render;
 657                 edit_draw_this_line (edit, b, row, start_column, end_column);
 658                 b = edit_move_forward (edit, b, 1, 0);
 659                 row++;
 660             }
 661         } else {
 662             curs_row = edit->curs_row;
 663
 664             if (force & REDRAW_BEFORE_CURSOR) {
 665                 if (start_row < curs_row) {
 666                     long upto = curs_row - 1 <= end_row ? curs_row - 1 : end_row;
 667                     row = start_row;
 668                     b = edit->start_display;
 669                     while (row <= upto) {
 670                         if (key_pending (edit))
 671                             goto exit_render;
 672                         edit_draw_this_line (edit, b, row, start_column, end_column);
 673                         b = edit_move_forward (edit, b, 1, 0);
 674                     }
 675                 }
 676             }
 677 /*          if (force & REDRAW_LINE)          ---> default */
 678             b = edit_bol (edit, edit->curs1);
 679             if (curs_row >= start_row && curs_row <= end_row) {
 680                 if (key_pending (edit))
 681                     goto exit_render;
 682                 edit_draw_this_line (edit, b, curs_row, start_column, end_column);
 683             }
 684             if (force & REDRAW_AFTER_CURSOR) {
 685                 if (end_row > curs_row) {
 686                     row = curs_row + 1 < start_row ? start_row : curs_row + 1;
 687                     b = edit_move_forward (edit, b, 1, 0);
 688                     while (row <= end_row) {
 689                         if (key_pending (edit))
 690                             goto exit_render;
 691                         edit_draw_this_line (edit, b, row, start_column, end_column);
 692                         b = edit_move_forward (edit, b, 1, 0);
 693                         row++;
 694                     }
 695                 }
 696             }
 697             if (force & REDRAW_LINE_ABOVE && curs_row >= 1) {
 698                 row = curs_row - 1;
 699                 b = edit_move_backward (edit, edit_bol (edit, edit->curs1), 1);
 700                 if (row >= start_row && row <= end_row) {
 701                     if (key_pending (edit))
 702                         goto exit_render;
 703                     edit_draw_this_line (edit, b, row, start_column, end_column);
 704                 }
 705             }
 706             if (force & REDRAW_LINE_BELOW && row < edit->num_widget_lines - 1) {
 707                 row = curs_row + 1;
 708                 b = edit_bol (edit, edit->curs1);
 709                 b = edit_move_forward (edit, b, 1, 0);
 710                 if (row >= start_row && row <= end_row) {
 711                     if (key_pending (edit))
 712                         goto exit_render;
 713                     edit_draw_this_line (edit, b, row, start_column, end_column);
 714                 }
 715             }
 716         }
 717     } else {
 718         if (prev_curs_row < edit->curs_row) {   /* with the new text highlighting, we must draw from the top down */
 719             edit_draw_this_char (edit, prev_curs, prev_curs_row);
 720             edit_draw_this_char (edit, edit->curs1, edit->curs_row);
 721         } else {
 722             edit_draw_this_char (edit, edit->curs1, edit->curs_row);
 723             edit_draw_this_char (edit, prev_curs, prev_curs_row);
 724         }
 725     }
 726
 727     edit->force = 0;
 728
 729     prev_curs_row = edit->curs_row;
 730     prev_curs = edit->curs1;
 731
 732   exit_render:
 733     edit->screen_modified = 0;
 734 }
 735
 736 static inline void
 737 edit_render (WEdit * edit, int page, int row_start, int col_start, int row_end, int col_end)
 738 {
 739     if (page)                   /* if it was an expose event, 'page' would be set */
 740         edit->force |= REDRAW_PAGE | REDRAW_IN_BOUNDS;
 741
 742     if (edit->force & REDRAW_COMPLETELY)
 743         buttonbar_redraw (find_buttonbar (edit->widget.parent));
 744     render_edit_text (edit, row_start, col_start, row_end, col_end);
 745     /*
 746      * edit->force != 0 means a key was pending and the redraw
 747      * was halted, so next time we must redraw everything in case stuff
 748      * was left undrawn from a previous key press.
 749      */
 750     if (edit->force)
 751         edit->force |= REDRAW_PAGE;
 752 }
 753
 754 void edit_render_keypress (WEdit * edit)
 755 {
 756     edit_render (edit, 0, 0, 0, 0, 0);
 757 }