1 /* 2 * textbox.c -- implements the text box 3 * 4 * ORIGINAL AUTHOR: Savio Lam ([email protected]) 5 * MODIFIED FOR LINUX KERNEL CONFIG BY: William Roadcap ([email protected]) 6 * 7 * This program is free software; you can redistribute it and/or 8 * modify it under the terms of the GNU General Public License 9 * as published by the Free Software Foundation; either version 2 10 * of the License, or (at your option) any later version. 11 * 12 * This program is distributed in the hope that it will be useful, 13 * but WITHOUT ANY WARRANTY; without even the implied warranty of 14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 15 * GNU General Public License for more details. 16 * 17 * You should have received a copy of the GNU General Public License 18 * along with this program; if not, write to the Free Software 19 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. 20 */ 21 22 #include "dialog.h" 23 24 static void back_lines(int n); 25 static void print_page(WINDOW * win, int height, int width); 26 static void print_line(WINDOW * win, int row, int width); 27 static char *get_line(void); 28 static void print_position(WINDOW * win, int height, int width); 29 30 static int hscroll, fd, file_size, bytes_read; 31 static int begin_reached = 1, end_reached, page_length; 32 static char *buf, *page; 33 34 /* 35 * Display text from a file in a dialog box. 36 */ 37 int dialog_textbox(const char *title, const char *file, int height, int width) 38 { 39 int i, x, y, cur_x, cur_y, fpos, key = 0; 40 int passed_end; 41 char search_term[MAX_LEN + 1]; 42 WINDOW *dialog, *text; 43 44 search_term[0] = '\0'; /* no search term entered yet */ 45 46 /* Open input file for reading */ 47 if ((fd = open(file, O_RDONLY)) == -1) { 48 endwin(); 49 fprintf(stderr, "\nCan't open input file in dialog_textbox().\n"); 50 exit(-1); 51 } 52 /* Get file size. Actually, 'file_size' is the real file size - 1, 53 since it's only the last byte offset from the beginning */ 54 if ((file_size = lseek(fd, 0, SEEK_END)) == -1) { 55 endwin(); 56 fprintf(stderr, "\nError getting file size in dialog_textbox().\n"); 57 exit(-1); 58 } 59 /* Restore file pointer to beginning of file after getting file size */ 60 if (lseek(fd, 0, SEEK_SET) == -1) { 61 endwin(); 62 fprintf(stderr, "\nError moving file pointer in dialog_textbox().\n"); 63 exit(-1); 64 } 65 /* Allocate space for read buffer */ 66 if ((buf = malloc(BUF_SIZE + 1)) == NULL) { 67 endwin(); 68 fprintf(stderr, "\nCan't allocate memory in dialog_textbox().\n"); 69 exit(-1); 70 } 71 if ((bytes_read = read(fd, buf, BUF_SIZE)) == -1) { 72 endwin(); 73 fprintf(stderr, "\nError reading file in dialog_textbox().\n"); 74 exit(-1); 75 } 76 buf[bytes_read] = '\0'; /* mark end of valid data */ 77 page = buf; /* page is pointer to start of page to be displayed */ 78 79 /* center dialog box on screen */ 80 x = (COLS - width) / 2; 81 y = (LINES - height) / 2; 82 83 draw_shadow(stdscr, y, x, height, width); 84 85 dialog = newwin(height, width, y, x); 86 keypad(dialog, TRUE); 87 88 /* Create window for text region, used for scrolling text */ 89 text = subwin(dialog, height - 4, width - 2, y + 1, x + 1); 90 wattrset(text, dlg.dialog.atr); 91 wbkgdset(text, dlg.dialog.atr & A_COLOR); 92 93 keypad(text, TRUE); 94 95 /* register the new window, along with its borders */ 96 draw_box(dialog, 0, 0, height, width, 97 dlg.dialog.atr, dlg.border.atr); 98 99 wattrset(dialog, dlg.border.atr); 100 mvwaddch(dialog, height - 3, 0, ACS_LTEE); 101 for (i = 0; i < width - 2; i++) 102 waddch(dialog, ACS_HLINE); 103 wattrset(dialog, dlg.dialog.atr); 104 wbkgdset(dialog, dlg.dialog.atr & A_COLOR); 105 waddch(dialog, ACS_RTEE); 106 107 print_title(dialog, title, width); 108 109 print_button(dialog, " Exit ", height - 2, width / 2 - 4, TRUE); 110 wnoutrefresh(dialog); 111 getyx(dialog, cur_y, cur_x); /* Save cursor position */ 112 113 /* Print first page of text */ 114 attr_clear(text, height - 4, width - 2, dlg.dialog.atr); 115 print_page(text, height - 4, width - 2); 116 print_position(dialog, height, width); 117 wmove(dialog, cur_y, cur_x); /* Restore cursor position */ 118 wrefresh(dialog); 119 120 while ((key != ESC) && (key != '\n')) { 121 key = wgetch(dialog); 122 switch (key) { 123 case 'E': /* Exit */ 124 case 'e': 125 case 'X': 126 case 'x': 127 delwin(dialog); 128 free(buf); 129 close(fd); 130 return 0; 131 case 'g': /* First page */ 132 case KEY_HOME: 133 if (!begin_reached) { 134 begin_reached = 1; 135 /* First page not in buffer? */ 136 if ((fpos = lseek(fd, 0, SEEK_CUR)) == -1) { 137 endwin(); 138 fprintf(stderr, "\nError moving file pointer in dialog_textbox().\n"); 139 exit(-1); 140 } 141 if (fpos > bytes_read) { /* Yes, we have to read it in */ 142 if (lseek(fd, 0, SEEK_SET) == -1) { 143 endwin(); 144 fprintf(stderr, "\nError moving file pointer in " 145 "dialog_textbox().\n"); 146 exit(-1); 147 } 148 if ((bytes_read = 149 read(fd, buf, BUF_SIZE)) == -1) { 150 endwin(); 151 fprintf(stderr, "\nError reading file in dialog_textbox().\n"); 152 exit(-1); 153 } 154 buf[bytes_read] = '\0'; 155 } 156 page = buf; 157 print_page(text, height - 4, width - 2); 158 print_position(dialog, height, width); 159 wmove(dialog, cur_y, cur_x); /* Restore cursor position */ 160 wrefresh(dialog); 161 } 162 break; 163 case 'G': /* Last page */ 164 case KEY_END: 165 166 end_reached = 1; 167 /* Last page not in buffer? */ 168 if ((fpos = lseek(fd, 0, SEEK_CUR)) == -1) { 169 endwin(); 170 fprintf(stderr, "\nError moving file pointer in dialog_textbox().\n"); 171 exit(-1); 172 } 173 if (fpos < file_size) { /* Yes, we have to read it in */ 174 if (lseek(fd, -BUF_SIZE, SEEK_END) == -1) { 175 endwin(); 176 fprintf(stderr, "\nError moving file pointer in dialog_textbox().\n"); 177 exit(-1); 178 } 179 if ((bytes_read = 180 read(fd, buf, BUF_SIZE)) == -1) { 181 endwin(); 182 fprintf(stderr, "\nError reading file in dialog_textbox().\n"); 183 exit(-1); 184 } 185 buf[bytes_read] = '\0'; 186 } 187 page = buf + bytes_read; 188 back_lines(height - 4); 189 print_page(text, height - 4, width - 2); 190 print_position(dialog, height, width); 191 wmove(dialog, cur_y, cur_x); /* Restore cursor position */ 192 wrefresh(dialog); 193 break; 194 case 'K': /* Previous line */ 195 case 'k': 196 case KEY_UP: 197 if (!begin_reached) { 198 back_lines(page_length + 1); 199 200 /* We don't call print_page() here but use scrolling to ensure 201 faster screen update. However, 'end_reached' and 202 'page_length' should still be updated, and 'page' should 203 point to start of next page. This is done by calling 204 get_line() in the following 'for' loop. */ 205 scrollok(text, TRUE); 206 wscrl(text, -1); /* Scroll text region down one line */ 207 scrollok(text, FALSE); 208 page_length = 0; 209 passed_end = 0; 210 for (i = 0; i < height - 4; i++) { 211 if (!i) { 212 /* print first line of page */ 213 print_line(text, 0, width - 2); 214 wnoutrefresh(text); 215 } else 216 /* Called to update 'end_reached' and 'page' */ 217 get_line(); 218 if (!passed_end) 219 page_length++; 220 if (end_reached && !passed_end) 221 passed_end = 1; 222 } 223 224 print_position(dialog, height, width); 225 wmove(dialog, cur_y, cur_x); /* Restore cursor position */ 226 wrefresh(dialog); 227 } 228 break; 229 case 'B': /* Previous page */ 230 case 'b': 231 case KEY_PPAGE: 232 if (begin_reached) 233 break; 234 back_lines(page_length + height - 4); 235 print_page(text, height - 4, width - 2); 236 print_position(dialog, height, width); 237 wmove(dialog, cur_y, cur_x); 238 wrefresh(dialog); 239 break; 240 case 'J': /* Next line */ 241 case 'j': 242 case KEY_DOWN: 243 if (!end_reached) { 244 begin_reached = 0; 245 scrollok(text, TRUE); 246 scroll(text); /* Scroll text region up one line */ 247 scrollok(text, FALSE); 248 print_line(text, height - 5, width - 2); 249 wnoutrefresh(text); 250 print_position(dialog, height, width); 251 wmove(dialog, cur_y, cur_x); /* Restore cursor position */ 252 wrefresh(dialog); 253 } 254 break; 255 case KEY_NPAGE: /* Next page */ 256 case ' ': 257 if (end_reached) 258 break; 259 260 begin_reached = 0; 261 print_page(text, height - 4, width - 2); 262 print_position(dialog, height, width); 263 wmove(dialog, cur_y, cur_x); 264 wrefresh(dialog); 265 break; 266 case '0': /* Beginning of line */ 267 case 'H': /* Scroll left */ 268 case 'h': 269 case KEY_LEFT: 270 if (hscroll <= 0) 271 break; 272 273 if (key == '0') 274 hscroll = 0; 275 else 276 hscroll--; 277 /* Reprint current page to scroll horizontally */ 278 back_lines(page_length); 279 print_page(text, height - 4, width - 2); 280 wmove(dialog, cur_y, cur_x); 281 wrefresh(dialog); 282 break; 283 case 'L': /* Scroll right */ 284 case 'l': 285 case KEY_RIGHT: 286 if (hscroll >= MAX_LEN) 287 break; 288 hscroll++; 289 /* Reprint current page to scroll horizontally */ 290 back_lines(page_length); 291 print_page(text, height - 4, width - 2); 292 wmove(dialog, cur_y, cur_x); 293 wrefresh(dialog); 294 break; 295 case ESC: 296 break; 297 } 298 } 299 300 delwin(dialog); 301 free(buf); 302 close(fd); 303 return -1; /* ESC pressed */ 304 } 305 306 /* 307 * Go back 'n' lines in text file. Called by dialog_textbox(). 308 * 'page' will be updated to point to the desired line in 'buf'. 309 */ 310 static void back_lines(int n) 311 { 312 int i, fpos; 313 314 begin_reached = 0; 315 /* We have to distinguish between end_reached and !end_reached 316 since at end of file, the line is not ended by a '\n'. 317 The code inside 'if' basically does a '--page' to move one 318 character backward so as to skip '\n' of the previous line */ 319 if (!end_reached) { 320 /* Either beginning of buffer or beginning of file reached? */ 321 if (page == buf) { 322 if ((fpos = lseek(fd, 0, SEEK_CUR)) == -1) { 323 endwin(); 324 fprintf(stderr, "\nError moving file pointer in " 325 "back_lines().\n"); 326 exit(-1); 327 } 328 if (fpos > bytes_read) { /* Not beginning of file yet */ 329 /* We've reached beginning of buffer, but not beginning of 330 file yet, so read previous part of file into buffer. 331 Note that we only move backward for BUF_SIZE/2 bytes, 332 but not BUF_SIZE bytes to avoid re-reading again in 333 print_page() later */ 334 /* Really possible to move backward BUF_SIZE/2 bytes? */ 335 if (fpos < BUF_SIZE / 2 + bytes_read) { 336 /* No, move less then */ 337 if (lseek(fd, 0, SEEK_SET) == -1) { 338 endwin(); 339 fprintf(stderr, "\nError moving file pointer in " 340 "back_lines().\n"); 341 exit(-1); 342 } 343 page = buf + fpos - bytes_read; 344 } else { /* Move backward BUF_SIZE/2 bytes */ 345 if (lseek (fd, -(BUF_SIZE / 2 + bytes_read), SEEK_CUR) == -1) { 346 endwin(); 347 fprintf(stderr, "\nError moving file pointer " 348 "in back_lines().\n"); 349 exit(-1); 350 } 351 page = buf + BUF_SIZE / 2; 352 } 353 if ((bytes_read = 354 read(fd, buf, BUF_SIZE)) == -1) { 355 endwin(); 356 fprintf(stderr, "\nError reading file in back_lines().\n"); 357 exit(-1); 358 } 359 buf[bytes_read] = '\0'; 360 } else { /* Beginning of file reached */ 361 begin_reached = 1; 362 return; 363 } 364 } 365 if (*(--page) != '\n') { /* '--page' here */ 366 /* Something's wrong... */ 367 endwin(); 368 fprintf(stderr, "\nInternal error in back_lines().\n"); 369 exit(-1); 370 } 371 } 372 /* Go back 'n' lines */ 373 for (i = 0; i < n; i++) 374 do { 375 if (page == buf) { 376 if ((fpos = lseek(fd, 0, SEEK_CUR)) == -1) { 377 endwin(); 378 fprintf(stderr, "\nError moving file pointer in back_lines().\n"); 379 exit(-1); 380 } 381 if (fpos > bytes_read) { 382 /* Really possible to move backward BUF_SIZE/2 bytes? */ 383 if (fpos < BUF_SIZE / 2 + bytes_read) { 384 /* No, move less then */ 385 if (lseek(fd, 0, SEEK_SET) == -1) { 386 endwin(); 387 fprintf(stderr, "\nError moving file pointer " 388 "in back_lines().\n"); 389 exit(-1); 390 } 391 page = buf + fpos - bytes_read; 392 } else { /* Move backward BUF_SIZE/2 bytes */ 393 if (lseek (fd, -(BUF_SIZE / 2 + bytes_read), SEEK_CUR) == -1) { 394 endwin(); 395 fprintf(stderr, "\nError moving file pointer" 396 " in back_lines().\n"); 397 exit(-1); 398 } 399 page = buf + BUF_SIZE / 2; 400 } 401 if ((bytes_read = 402 read(fd, buf, BUF_SIZE)) == -1) { 403 endwin(); 404 fprintf(stderr, "\nError reading file in " 405 "back_lines().\n"); 406 exit(-1); 407 } 408 buf[bytes_read] = '\0'; 409 } else { /* Beginning of file reached */ 410 begin_reached = 1; 411 return; 412 } 413 } 414 } while (*(--page) != '\n'); 415 page++; 416 } 417 418 /* 419 * Print a new page of text. Called by dialog_textbox(). 420 */ 421 static void print_page(WINDOW * win, int height, int width) 422 { 423 int i, passed_end = 0; 424 425 page_length = 0; 426 for (i = 0; i < height; i++) { 427 print_line(win, i, width); 428 if (!passed_end) 429 page_length++; 430 if (end_reached && !passed_end) 431 passed_end = 1; 432 } 433 wnoutrefresh(win); 434 } 435 436 /* 437 * Print a new line of text. Called by dialog_textbox() and print_page(). 438 */ 439 static void print_line(WINDOW * win, int row, int width) 440 { 441 int y, x; 442 char *line; 443 444 line = get_line(); 445 line += MIN(strlen(line), hscroll); /* Scroll horizontally */ 446 wmove(win, row, 0); /* move cursor to correct line */ 447 waddch(win, ' '); 448 waddnstr(win, line, MIN(strlen(line), width - 2)); 449 450 getyx(win, y, x); 451 /* Clear 'residue' of previous line */ 452 #if OLD_NCURSES 453 { 454 int i; 455 for (i = 0; i < width - x; i++) 456 waddch(win, ' '); 457 } 458 #else 459 wclrtoeol(win); 460 #endif 461 } 462 463 /* 464 * Return current line of text. Called by dialog_textbox() and print_line(). 465 * 'page' should point to start of current line before calling, and will be 466 * updated to point to start of next line. 467 */ 468 static char *get_line(void) 469 { 470 int i = 0, fpos; 471 static char line[MAX_LEN + 1]; 472 473 end_reached = 0; 474 while (*page != '\n') { 475 if (*page == '\0') { 476 /* Either end of file or end of buffer reached */ 477 if ((fpos = lseek(fd, 0, SEEK_CUR)) == -1) { 478 endwin(); 479 fprintf(stderr, "\nError moving file pointer in " 480 "get_line().\n"); 481 exit(-1); 482 } 483 if (fpos < file_size) { /* Not end of file yet */ 484 /* We've reached end of buffer, but not end of file yet, 485 so read next part of file into buffer */ 486 if ((bytes_read = 487 read(fd, buf, BUF_SIZE)) == -1) { 488 endwin(); 489 fprintf(stderr, "\nError reading file in get_line().\n"); 490 exit(-1); 491 } 492 buf[bytes_read] = '\0'; 493 page = buf; 494 } else { 495 if (!end_reached) 496 end_reached = 1; 497 break; 498 } 499 } else if (i < MAX_LEN) 500 line[i++] = *(page++); 501 else { 502 /* Truncate lines longer than MAX_LEN characters */ 503 if (i == MAX_LEN) 504 line[i++] = '\0'; 505 page++; 506 } 507 } 508 if (i <= MAX_LEN) 509 line[i] = '\0'; 510 if (!end_reached) 511 page++; /* move pass '\n' */ 512 513 return line; 514 } 515 516 /* 517 * Print current position 518 */ 519 static void print_position(WINDOW * win, int height, int width) 520 { 521 int fpos, percent; 522 523 if ((fpos = lseek(fd, 0, SEEK_CUR)) == -1) { 524 endwin(); 525 fprintf(stderr, "\nError moving file pointer in print_position().\n"); 526 exit(-1); 527 } 528 wattrset(win, dlg.position_indicator.atr); 529 wbkgdset(win, dlg.position_indicator.atr & A_COLOR); 530 percent = !file_size ? 531 100 : ((fpos - bytes_read + page - buf) * 100) / file_size; 532 wmove(win, height - 3, width - 9); 533 wprintw(win, "(%3d%%)", percent); 534 } 535