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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
24static void back_lines(int n);
25static void print_page(WINDOW * win, int height, int width);
26static void print_line(WINDOW * win, int row, int width);
27static char *get_line(void);
28static void print_position(WINDOW * win);
29
30static int hscroll;
31static int begin_reached, end_reached, page_length;
32static const char *buf;
33static const char *page;
34
35/*
36 * refresh window content
37 */
38static void refresh_text_box(WINDOW *dialog, WINDOW *box, int boxh, int boxw,
39 int cur_y, int cur_x)
40{
41 print_page(box, boxh, boxw);
42 print_position(dialog);
43 wmove(dialog, cur_y, cur_x); /* Restore cursor position */
44 wrefresh(dialog);
45}
46
47
48/*
49 * Display text from a file in a dialog box.
50 */
51int dialog_textbox(const char *title, const char *tbuf,
52 int initial_height, int initial_width)
53{
54 int i, x, y, cur_x, cur_y, key = 0;
55 int height, width, boxh, boxw;
56 int passed_end;
57 WINDOW *dialog, *box;
58
59 begin_reached = 1;
60 end_reached = 0;
61 page_length = 0;
62 hscroll = 0;
63 buf = tbuf;
64 page = buf; /* page is pointer to start of page to be displayed */
65
66do_resize:
67 getmaxyx(stdscr, height, width);
68 if (height < 8 || width < 8)
69 return -ERRDISPLAYTOOSMALL;
70 if (initial_height != 0)
71 height = initial_height;
72 else
73 if (height > 4)
74 height -= 4;
75 else
76 height = 0;
77 if (initial_width != 0)
78 width = initial_width;
79 else
80 if (width > 5)
81 width -= 5;
82 else
83 width = 0;
84
85 /* center dialog box on screen */
86 x = (COLS - width) / 2;
87 y = (LINES - height) / 2;
88
89 draw_shadow(stdscr, y, x, height, width);
90
91 dialog = newwin(height, width, y, x);
92 keypad(dialog, TRUE);
93
94 /* Create window for box region, used for scrolling text */
95 boxh = height - 4;
96 boxw = width - 2;
97 box = subwin(dialog, boxh, boxw, y + 1, x + 1);
98 wattrset(box, dlg.dialog.atr);
99 wbkgdset(box, dlg.dialog.atr & A_COLOR);
100
101 keypad(box, TRUE);
102
103 /* register the new window, along with its borders */
104 draw_box(dialog, 0, 0, height, width,
105 dlg.dialog.atr, dlg.border.atr);
106
107 wattrset(dialog, dlg.border.atr);
108 mvwaddch(dialog, height - 3, 0, ACS_LTEE);
109 for (i = 0; i < width - 2; i++)
110 waddch(dialog, ACS_HLINE);
111 wattrset(dialog, dlg.dialog.atr);
112 wbkgdset(dialog, dlg.dialog.atr & A_COLOR);
113 waddch(dialog, ACS_RTEE);
114
115 print_title(dialog, title, width);
116
117 print_button(dialog, gettext(" Exit "), height - 2, width / 2 - 4, TRUE);
118 wnoutrefresh(dialog);
119 getyx(dialog, cur_y, cur_x); /* Save cursor position */
120
121 /* Print first page of text */
122 attr_clear(box, boxh, boxw, dlg.dialog.atr);
123 refresh_text_box(dialog, box, boxh, boxw, cur_y, cur_x);
124
125 while ((key != KEY_ESC) && (key != '\n')) {
126 key = wgetch(dialog);
127 switch (key) {
128 case 'E': /* Exit */
129 case 'e':
130 case 'X':
131 case 'x':
132 delwin(box);
133 delwin(dialog);
134 return 0;
135 case 'g': /* First page */
136 case KEY_HOME:
137 if (!begin_reached) {
138 begin_reached = 1;
139 page = buf;
140 refresh_text_box(dialog, box, boxh, boxw,
141 cur_y, cur_x);
142 }
143 break;
144 case 'G': /* Last page */
145 case KEY_END:
146
147 end_reached = 1;
148 /* point to last char in buf */
149 page = buf + strlen(buf);
150 back_lines(boxh);
151 refresh_text_box(dialog, box, boxh, boxw,
152 cur_y, cur_x);
153 break;
154 case 'K': /* Previous line */
155 case 'k':
156 case KEY_UP:
157 if (!begin_reached) {
158 back_lines(page_length + 1);
159
160 /* We don't call print_page() here but use
161 * scrolling to ensure faster screen update.
162 * However, 'end_reached' and 'page_length'
163 * should still be updated, and 'page' should
164 * point to start of next page. This is done
165 * by calling get_line() in the following
166 * 'for' loop. */
167 scrollok(box, TRUE);
168 wscrl(box, -1); /* Scroll box region down one line */
169 scrollok(box, FALSE);
170 page_length = 0;
171 passed_end = 0;
172 for (i = 0; i < boxh; i++) {
173 if (!i) {
174 /* print first line of page */
175 print_line(box, 0, boxw);
176 wnoutrefresh(box);
177 } else
178 /* Called to update 'end_reached' and 'page' */
179 get_line();
180 if (!passed_end)
181 page_length++;
182 if (end_reached && !passed_end)
183 passed_end = 1;
184 }
185
186 print_position(dialog);
187 wmove(dialog, cur_y, cur_x); /* Restore cursor position */
188 wrefresh(dialog);
189 }
190 break;
191 case 'B': /* Previous page */
192 case 'b':
193 case KEY_PPAGE:
194 if (begin_reached)
195 break;
196 back_lines(page_length + boxh);
197 refresh_text_box(dialog, box, boxh, boxw,
198 cur_y, cur_x);
199 break;
200 case 'J': /* Next line */
201 case 'j':
202 case KEY_DOWN:
203 if (!end_reached) {
204 begin_reached = 0;
205 scrollok(box, TRUE);
206 scroll(box); /* Scroll box region up one line */
207 scrollok(box, FALSE);
208 print_line(box, boxh - 1, boxw);
209 wnoutrefresh(box);
210 print_position(dialog);
211 wmove(dialog, cur_y, cur_x); /* Restore cursor position */
212 wrefresh(dialog);
213 }
214 break;
215 case KEY_NPAGE: /* Next page */
216 case ' ':
217 if (end_reached)
218 break;
219
220 begin_reached = 0;
221 refresh_text_box(dialog, box, boxh, boxw,
222 cur_y, cur_x);
223 break;
224 case '0': /* Beginning of line */
225 case 'H': /* Scroll left */
226 case 'h':
227 case KEY_LEFT:
228 if (hscroll <= 0)
229 break;
230
231 if (key == '0')
232 hscroll = 0;
233 else
234 hscroll--;
235 /* Reprint current page to scroll horizontally */
236 back_lines(page_length);
237 refresh_text_box(dialog, box, boxh, boxw,
238 cur_y, cur_x);
239 break;
240 case 'L': /* Scroll right */
241 case 'l':
242 case KEY_RIGHT:
243 if (hscroll >= MAX_LEN)
244 break;
245 hscroll++;
246 /* Reprint current page to scroll horizontally */
247 back_lines(page_length);
248 refresh_text_box(dialog, box, boxh, boxw,
249 cur_y, cur_x);
250 break;
251 case KEY_ESC:
252 key = on_key_esc(dialog);
253 break;
254 case KEY_RESIZE:
255 back_lines(height);
256 delwin(box);
257 delwin(dialog);
258 on_key_resize();
259 goto do_resize;
260 }
261 }
262 delwin(box);
263 delwin(dialog);
264 return key; /* ESC pressed */
265}
266
267/*
268 * Go back 'n' lines in text. Called by dialog_textbox().
269 * 'page' will be updated to point to the desired line in 'buf'.
270 */
271static void back_lines(int n)
272{
273 int i;
274
275 begin_reached = 0;
276 /* Go back 'n' lines */
277 for (i = 0; i < n; i++) {
278 if (*page == '\0') {
279 if (end_reached) {
280 end_reached = 0;
281 continue;
282 }
283 }
284 if (page == buf) {
285 begin_reached = 1;
286 return;
287 }
288 page--;
289 do {
290 if (page == buf) {
291 begin_reached = 1;
292 return;
293 }
294 page--;
295 } while (*page != '\n');
296 page++;
297 }
298}
299
300/*
301 * Print a new page of text. Called by dialog_textbox().
302 */
303static void print_page(WINDOW * win, int height, int width)
304{
305 int i, passed_end = 0;
306
307 page_length = 0;
308 for (i = 0; i < height; i++) {
309 print_line(win, i, width);
310 if (!passed_end)
311 page_length++;
312 if (end_reached && !passed_end)
313 passed_end = 1;
314 }
315 wnoutrefresh(win);
316}
317
318/*
319 * Print a new line of text. Called by dialog_textbox() and print_page().
320 */
321static void print_line(WINDOW * win, int row, int width)
322{
323 char *line;
324
325 line = get_line();
326 line += MIN(strlen(line), hscroll); /* Scroll horizontally */
327 wmove(win, row, 0); /* move cursor to correct line */
328 waddch(win, ' ');
329 waddnstr(win, line, MIN(strlen(line), width - 2));
330
331 /* Clear 'residue' of previous line */
332#if OLD_NCURSES
333 {
334 int x = getcurx(win);
335 int i;
336 for (i = 0; i < width - x; i++)
337 waddch(win, ' ');
338 }
339#else
340 wclrtoeol(win);
341#endif
342}
343
344/*
345 * Return current line of text. Called by dialog_textbox() and print_line().
346 * 'page' should point to start of current line before calling, and will be
347 * updated to point to start of next line.
348 */
349static char *get_line(void)
350{
351 int i = 0;
352 static char line[MAX_LEN + 1];
353
354 end_reached = 0;
355 while (*page != '\n') {
356 if (*page == '\0') {
357 if (!end_reached) {
358 end_reached = 1;
359 break;
360 }
361 } else if (i < MAX_LEN)
362 line[i++] = *(page++);
363 else {
364 /* Truncate lines longer than MAX_LEN characters */
365 if (i == MAX_LEN)
366 line[i++] = '\0';
367 page++;
368 }
369 }
370 if (i <= MAX_LEN)
371 line[i] = '\0';
372 if (!end_reached)
373 page++; /* move pass '\n' */
374
375 return line;
376}
377
378/*
379 * Print current position
380 */
381static void print_position(WINDOW * win)
382{
383 int percent;
384
385 wattrset(win, dlg.position_indicator.atr);
386 wbkgdset(win, dlg.position_indicator.atr & A_COLOR);
387 percent = (page - buf) * 100 / strlen(buf);
388 wmove(win, getmaxy(win) - 3, getmaxx(win) - 9);
389 wprintw(win, "(%3d%%)", percent);
390}