add external kernel tree support
[openwrt.git] / scripts / config / lxdialog / textbox.c
1 /*
2 * textbox.c -- implements the text box
3 *
4 * ORIGINAL AUTHOR: Savio Lam (lam836@cs.cuhk.hk)
5 * MODIFIED FOR LINUX KERNEL CONFIG BY: William Roadcap (roadcap@cfw.com)
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, dialog_attr);
91 wbkgdset(text, dialog_attr & 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, dialog_attr, border_attr);
97
98 wattrset(dialog, border_attr);
99 mvwaddch(dialog, height - 3, 0, ACS_LTEE);
100 for (i = 0; i < width - 2; i++)
101 waddch(dialog, ACS_HLINE);
102 wattrset(dialog, dialog_attr);
103 wbkgdset(dialog, dialog_attr & A_COLOR);
104 waddch(dialog, ACS_RTEE);
105
106 print_title(dialog, title, width);
107
108 print_button(dialog, " Exit ", height - 2, width / 2 - 4, TRUE);
109 wnoutrefresh(dialog);
110 getyx(dialog, cur_y, cur_x); /* Save cursor position */
111
112 /* Print first page of text */
113 attr_clear(text, height - 4, width - 2, dialog_attr);
114 print_page(text, height - 4, width - 2);
115 print_position(dialog, height, width);
116 wmove(dialog, cur_y, cur_x); /* Restore cursor position */
117 wrefresh(dialog);
118
119 while ((key != ESC) && (key != '\n')) {
120 key = wgetch(dialog);
121 switch (key) {
122 case 'E': /* Exit */
123 case 'e':
124 case 'X':
125 case 'x':
126 delwin(dialog);
127 free(buf);
128 close(fd);
129 return 0;
130 case 'g': /* First page */
131 case KEY_HOME:
132 if (!begin_reached) {
133 begin_reached = 1;
134 /* First page not in buffer? */
135 if ((fpos = lseek(fd, 0, SEEK_CUR)) == -1) {
136 endwin();
137 fprintf(stderr, "\nError moving file pointer in dialog_textbox().\n");
138 exit(-1);
139 }
140 if (fpos > bytes_read) { /* Yes, we have to read it in */
141 if (lseek(fd, 0, SEEK_SET) == -1) {
142 endwin();
143 fprintf(stderr, "\nError moving file pointer in "
144 "dialog_textbox().\n");
145 exit(-1);
146 }
147 if ((bytes_read =
148 read(fd, buf, BUF_SIZE)) == -1) {
149 endwin();
150 fprintf(stderr, "\nError reading file in dialog_textbox().\n");
151 exit(-1);
152 }
153 buf[bytes_read] = '\0';
154 }
155 page = buf;
156 print_page(text, height - 4, width - 2);
157 print_position(dialog, height, width);
158 wmove(dialog, cur_y, cur_x); /* Restore cursor position */
159 wrefresh(dialog);
160 }
161 break;
162 case 'G': /* Last page */
163 case KEY_END:
164
165 end_reached = 1;
166 /* Last page not in buffer? */
167 if ((fpos = lseek(fd, 0, SEEK_CUR)) == -1) {
168 endwin();
169 fprintf(stderr, "\nError moving file pointer in dialog_textbox().\n");
170 exit(-1);
171 }
172 if (fpos < file_size) { /* Yes, we have to read it in */
173 if (lseek(fd, -BUF_SIZE, SEEK_END) == -1) {
174 endwin();
175 fprintf(stderr, "\nError moving file pointer in dialog_textbox().\n");
176 exit(-1);
177 }
178 if ((bytes_read =
179 read(fd, buf, BUF_SIZE)) == -1) {
180 endwin();
181 fprintf(stderr, "\nError reading file in dialog_textbox().\n");
182 exit(-1);
183 }
184 buf[bytes_read] = '\0';
185 }
186 page = buf + bytes_read;
187 back_lines(height - 4);
188 print_page(text, height - 4, width - 2);
189 print_position(dialog, height, width);
190 wmove(dialog, cur_y, cur_x); /* Restore cursor position */
191 wrefresh(dialog);
192 break;
193 case 'K': /* Previous line */
194 case 'k':
195 case KEY_UP:
196 if (!begin_reached) {
197 back_lines(page_length + 1);
198
199 /* We don't call print_page() here but use scrolling to ensure
200 faster screen update. However, 'end_reached' and
201 'page_length' should still be updated, and 'page' should
202 point to start of next page. This is done by calling
203 get_line() in the following 'for' loop. */
204 scrollok(text, TRUE);
205 wscrl(text, -1); /* Scroll text region down one line */
206 scrollok(text, FALSE);
207 page_length = 0;
208 passed_end = 0;
209 for (i = 0; i < height - 4; i++) {
210 if (!i) {
211 /* print first line of page */
212 print_line(text, 0, width - 2);
213 wnoutrefresh(text);
214 } else
215 /* Called to update 'end_reached' and 'page' */
216 get_line();
217 if (!passed_end)
218 page_length++;
219 if (end_reached && !passed_end)
220 passed_end = 1;
221 }
222
223 print_position(dialog, height, width);
224 wmove(dialog, cur_y, cur_x); /* Restore cursor position */
225 wrefresh(dialog);
226 }
227 break;
228 case 'B': /* Previous page */
229 case 'b':
230 case KEY_PPAGE:
231 if (begin_reached)
232 break;
233 back_lines(page_length + height - 4);
234 print_page(text, height - 4, width - 2);
235 print_position(dialog, height, width);
236 wmove(dialog, cur_y, cur_x);
237 wrefresh(dialog);
238 break;
239 case 'J': /* Next line */
240 case 'j':
241 case KEY_DOWN:
242 if (!end_reached) {
243 begin_reached = 0;
244 scrollok(text, TRUE);
245 scroll(text); /* Scroll text region up one line */
246 scrollok(text, FALSE);
247 print_line(text, height - 5, width - 2);
248 wnoutrefresh(text);
249 print_position(dialog, height, width);
250 wmove(dialog, cur_y, cur_x); /* Restore cursor position */
251 wrefresh(dialog);
252 }
253 break;
254 case KEY_NPAGE: /* Next page */
255 case ' ':
256 if (end_reached)
257 break;
258
259 begin_reached = 0;
260 print_page(text, height - 4, width - 2);
261 print_position(dialog, height, width);
262 wmove(dialog, cur_y, cur_x);
263 wrefresh(dialog);
264 break;
265 case '0': /* Beginning of line */
266 case 'H': /* Scroll left */
267 case 'h':
268 case KEY_LEFT:
269 if (hscroll <= 0)
270 break;
271
272 if (key == '0')
273 hscroll = 0;
274 else
275 hscroll--;
276 /* Reprint current page to scroll horizontally */
277 back_lines(page_length);
278 print_page(text, height - 4, width - 2);
279 wmove(dialog, cur_y, cur_x);
280 wrefresh(dialog);
281 break;
282 case 'L': /* Scroll right */
283 case 'l':
284 case KEY_RIGHT:
285 if (hscroll >= MAX_LEN)
286 break;
287 hscroll++;
288 /* Reprint current page to scroll horizontally */
289 back_lines(page_length);
290 print_page(text, height - 4, width - 2);
291 wmove(dialog, cur_y, cur_x);
292 wrefresh(dialog);
293 break;
294 case ESC:
295 break;
296 }
297 }
298
299 delwin(dialog);
300 free(buf);
301 close(fd);
302 return -1; /* ESC pressed */
303 }
304
305 /*
306 * Go back 'n' lines in text file. Called by dialog_textbox().
307 * 'page' will be updated to point to the desired line in 'buf'.
308 */
309 static void back_lines(int n)
310 {
311 int i, fpos;
312
313 begin_reached = 0;
314 /* We have to distinguish between end_reached and !end_reached
315 since at end of file, the line is not ended by a '\n'.
316 The code inside 'if' basically does a '--page' to move one
317 character backward so as to skip '\n' of the previous line */
318 if (!end_reached) {
319 /* Either beginning of buffer or beginning of file reached? */
320 if (page == buf) {
321 if ((fpos = lseek(fd, 0, SEEK_CUR)) == -1) {
322 endwin();
323 fprintf(stderr, "\nError moving file pointer in "
324 "back_lines().\n");
325 exit(-1);
326 }
327 if (fpos > bytes_read) { /* Not beginning of file yet */
328 /* We've reached beginning of buffer, but not beginning of
329 file yet, so read previous part of file into buffer.
330 Note that we only move backward for BUF_SIZE/2 bytes,
331 but not BUF_SIZE bytes to avoid re-reading again in
332 print_page() later */
333 /* Really possible to move backward BUF_SIZE/2 bytes? */
334 if (fpos < BUF_SIZE / 2 + bytes_read) {
335 /* No, move less then */
336 if (lseek(fd, 0, SEEK_SET) == -1) {
337 endwin();
338 fprintf(stderr, "\nError moving file pointer in "
339 "back_lines().\n");
340 exit(-1);
341 }
342 page = buf + fpos - bytes_read;
343 } else { /* Move backward BUF_SIZE/2 bytes */
344 if (lseek (fd, -(BUF_SIZE / 2 + bytes_read), SEEK_CUR) == -1) {
345 endwin();
346 fprintf(stderr, "\nError moving file pointer "
347 "in back_lines().\n");
348 exit(-1);
349 }
350 page = buf + BUF_SIZE / 2;
351 }
352 if ((bytes_read =
353 read(fd, buf, BUF_SIZE)) == -1) {
354 endwin();
355 fprintf(stderr, "\nError reading file in back_lines().\n");
356 exit(-1);
357 }
358 buf[bytes_read] = '\0';
359 } else { /* Beginning of file reached */
360 begin_reached = 1;
361 return;
362 }
363 }
364 if (*(--page) != '\n') { /* '--page' here */
365 /* Something's wrong... */
366 endwin();
367 fprintf(stderr, "\nInternal error in back_lines().\n");
368 exit(-1);
369 }
370 }
371 /* Go back 'n' lines */
372 for (i = 0; i < n; i++)
373 do {
374 if (page == buf) {
375 if ((fpos = lseek(fd, 0, SEEK_CUR)) == -1) {
376 endwin();
377 fprintf(stderr, "\nError moving file pointer in back_lines().\n");
378 exit(-1);
379 }
380 if (fpos > bytes_read) {
381 /* Really possible to move backward BUF_SIZE/2 bytes? */
382 if (fpos < BUF_SIZE / 2 + bytes_read) {
383 /* No, move less then */
384 if (lseek(fd, 0, SEEK_SET) == -1) {
385 endwin();
386 fprintf(stderr, "\nError moving file pointer "
387 "in back_lines().\n");
388 exit(-1);
389 }
390 page = buf + fpos - bytes_read;
391 } else { /* Move backward BUF_SIZE/2 bytes */
392 if (lseek (fd, -(BUF_SIZE / 2 + bytes_read), SEEK_CUR) == -1) {
393 endwin();
394 fprintf(stderr, "\nError moving file pointer"
395 " in back_lines().\n");
396 exit(-1);
397 }
398 page = buf + BUF_SIZE / 2;
399 }
400 if ((bytes_read =
401 read(fd, buf, BUF_SIZE)) == -1) {
402 endwin();
403 fprintf(stderr, "\nError reading file in "
404 "back_lines().\n");
405 exit(-1);
406 }
407 buf[bytes_read] = '\0';
408 } else { /* Beginning of file reached */
409 begin_reached = 1;
410 return;
411 }
412 }
413 } while (*(--page) != '\n');
414 page++;
415 }
416
417 /*
418 * Print a new page of text. Called by dialog_textbox().
419 */
420 static void print_page(WINDOW * win, int height, int width)
421 {
422 int i, passed_end = 0;
423
424 page_length = 0;
425 for (i = 0; i < height; i++) {
426 print_line(win, i, width);
427 if (!passed_end)
428 page_length++;
429 if (end_reached && !passed_end)
430 passed_end = 1;
431 }
432 wnoutrefresh(win);
433 }
434
435 /*
436 * Print a new line of text. Called by dialog_textbox() and print_page().
437 */
438 static void print_line(WINDOW * win, int row, int width)
439 {
440 int y, x;
441 char *line;
442
443 line = get_line();
444 line += MIN(strlen(line), hscroll); /* Scroll horizontally */
445 wmove(win, row, 0); /* move cursor to correct line */
446 waddch(win, ' ');
447 waddnstr(win, line, MIN(strlen(line), width - 2));
448
449 getyx(win, y, x);
450 /* Clear 'residue' of previous line */
451 #if OLD_NCURSES
452 {
453 int i;
454 for (i = 0; i < width - x; i++)
455 waddch(win, ' ');
456 }
457 #else
458 wclrtoeol(win);
459 #endif
460 }
461
462 /*
463 * Return current line of text. Called by dialog_textbox() and print_line().
464 * 'page' should point to start of current line before calling, and will be
465 * updated to point to start of next line.
466 */
467 static char *get_line(void)
468 {
469 int i = 0, fpos;
470 static char line[MAX_LEN + 1];
471
472 end_reached = 0;
473 while (*page != '\n') {
474 if (*page == '\0') {
475 /* Either end of file or end of buffer reached */
476 if ((fpos = lseek(fd, 0, SEEK_CUR)) == -1) {
477 endwin();
478 fprintf(stderr, "\nError moving file pointer in "
479 "get_line().\n");
480 exit(-1);
481 }
482 if (fpos < file_size) { /* Not end of file yet */
483 /* We've reached end of buffer, but not end of file yet,
484 so read next part of file into buffer */
485 if ((bytes_read =
486 read(fd, buf, BUF_SIZE)) == -1) {
487 endwin();
488 fprintf(stderr, "\nError reading file in get_line().\n");
489 exit(-1);
490 }
491 buf[bytes_read] = '\0';
492 page = buf;
493 } else {
494 if (!end_reached)
495 end_reached = 1;
496 break;
497 }
498 } else if (i < MAX_LEN)
499 line[i++] = *(page++);
500 else {
501 /* Truncate lines longer than MAX_LEN characters */
502 if (i == MAX_LEN)
503 line[i++] = '\0';
504 page++;
505 }
506 }
507 if (i <= MAX_LEN)
508 line[i] = '\0';
509 if (!end_reached)
510 page++; /* move pass '\n' */
511
512 return line;
513 }
514
515 /*
516 * Print current position
517 */
518 static void print_position(WINDOW * win, int height, int width)
519 {
520 int fpos, percent;
521
522 if ((fpos = lseek(fd, 0, SEEK_CUR)) == -1) {
523 endwin();
524 fprintf(stderr, "\nError moving file pointer in print_position().\n");
525 exit(-1);
526 }
527 wattrset(win, position_indicator_attr);
528 wbkgdset(win, position_indicator_attr & A_COLOR);
529 percent = !file_size ?
530 100 : ((fpos - bytes_read + page - buf) * 100) / file_size;
531 wmove(win, height - 3, width - 9);
532 wprintw(win, "(%3d%%)", percent);
533 }
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