1 /*
2 * $Id: tailbox.c,v 1.79 2020/11/21 21:31:49 tom Exp $
3 *
4 * tailbox.c -- implements the tail box
5 *
6 * Copyright 2000-2019,2020 Thomas E. Dickey
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU Lesser General Public License, version 2.1
10 * as published by the Free Software Foundation.
11 *
12 * This program is distributed in the hope that it will be useful, but
13 * WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
16 *
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with this program; if not, write to
19 * Free Software Foundation, Inc.
20 * 51 Franklin St., Fifth Floor
21 * Boston, MA 02110, USA.
22 *
23 * An earlier version of this program lists as authors
24 * Pasquale De Marco (demarco_p@abramo.it)
25 */
26
27 #include <dialog.h>
28 #include <dlg_keys.h>
29 #include <sys/stat.h>
30
31 typedef struct {
32 DIALOG_CALLBACK obj;
33 WINDOW *text;
34 const char **buttons;
35 int hscroll;
36 int old_hscroll;
37 char line[MAX_LEN + 2];
38 off_t last_pos;
39 } MY_OBJ;
40
41 /*
42 * Return current line of text.
43 */
44 static char *
get_line(MY_OBJ * obj)45 get_line(MY_OBJ * obj)
46 {
47 FILE *fp = obj->obj.input;
48 int col = -(obj->hscroll);
49 int j, tmpint, ch;
50
51 do {
52 if (((ch = getc(fp)) == EOF) && !feof(fp))
53 dlg_exiterr("Error moving file pointer in get_line().");
54 else if (!feof(fp) && (ch != '\n')) {
55 if ((ch == TAB) && (dialog_vars.tab_correct)) {
56 tmpint = dialog_state.tab_len
57 - ((col + obj->hscroll) % dialog_state.tab_len);
58 for (j = 0; j < tmpint; j++) {
59 if (col >= 0 && col < MAX_LEN)
60 obj->line[col] = ' ';
61 ++col;
62 }
63 } else {
64 if (col >= 0)
65 obj->line[col] = (char) ch;
66 ++col;
67 }
68 if (col >= MAX_LEN)
69 break;
70 }
71 } while (!feof(fp) && (ch != '\n'));
72
73 if (col < 0)
74 col = 0;
75 obj->line[col] = '\0';
76
77 return obj->line;
78 }
79
80 /*
81 * Print a new line of text.
82 */
83 static void
print_line(MY_OBJ * obj,WINDOW * win,int row,int width)84 print_line(MY_OBJ * obj, WINDOW *win, int row, int width)
85 {
86 int i, y, x;
87 char *line = get_line(obj);
88
89 (void) wmove(win, row, 0); /* move cursor to correct line */
90 (void) waddch(win, ' ');
91 (void) waddnstr(win, line, MIN((int) strlen(line), width - 2));
92
93 getyx(win, y, x);
94 (void) y;
95 /* Clear 'residue' of previous line */
96 for (i = 0; i < width - x; i++)
97 (void) waddch(win, ' ');
98 }
99
100 /*
101 * Go back 'target' lines in text file. BUFSIZ has to be in 'size_t' range.
102 */
103 static void
last_lines(MY_OBJ * obj,int target)104 last_lines(MY_OBJ * obj, int target)
105 {
106 FILE *fp = obj->obj.input;
107 long fpos = 0;
108
109 if (fseek(fp, 0L, SEEK_END) == -1
110 || (fpos = ftell(fp)) < 0)
111 dlg_exiterr("Error moving file pointer in last_lines().");
112
113 if (fpos != 0) {
114 long offset = 0;
115
116 ++target;
117 for (;;) {
118 size_t inx;
119 size_t size_to_read;
120 size_t size_as_read;
121 int count = 0;
122 char buf[BUFSIZ + 1];
123
124 if (fpos >= BUFSIZ) {
125 size_to_read = BUFSIZ;
126 } else {
127 size_to_read = (size_t) fpos;
128 }
129 fpos = fpos - (long) size_to_read;
130 if (fseek(fp, fpos, SEEK_SET) == -1)
131 dlg_exiterr("Error moving file pointer in last_lines().");
132 size_as_read = fread(buf, sizeof(char), size_to_read, fp);
133 if (ferror(fp))
134 dlg_exiterr("Error reading file in last_lines().");
135
136 if (size_as_read == 0) {
137 fpos = 0;
138 offset = 0;
139 break;
140 }
141
142 offset += (long) size_as_read;
143 for (inx = size_as_read - 1; inx != 0; --inx) {
144 if (buf[inx] == '\n') {
145 if (++count > target)
146 break;
147 offset = (long) (inx + 1);
148 }
149 }
150
151 if (count > target) {
152 break;
153 } else if (fpos == 0) {
154 offset = 0;
155 break;
156 }
157 }
158
159 if (fseek(fp, fpos + offset, SEEK_SET) == -1)
160 dlg_exiterr("Error moving file pointer in last_lines().");
161 }
162 }
163
164 /*
165 * Print a new page of text.
166 */
167 static void
print_page(MY_OBJ * obj,int height,int width)168 print_page(MY_OBJ * obj, int height, int width)
169 {
170 int i;
171
172 for (i = 0; i < height; i++) {
173 print_line(obj, obj->text, i, width);
174 }
175 (void) wnoutrefresh(obj->text);
176 }
177
178 static void
print_last_page(MY_OBJ * obj)179 print_last_page(MY_OBJ * obj)
180 {
181 int high = getmaxy(obj->obj.win) - (2 * MARGIN + (obj->obj.bg_task ? 1 : 3));
182 int wide = getmaxx(obj->text);
183
184 last_lines(obj, high);
185 print_page(obj, high, wide);
186 }
187
188 static void
repaint_text(MY_OBJ * obj)189 repaint_text(MY_OBJ * obj)
190 {
191 FILE *fp = obj->obj.input;
192 int cur_y, cur_x;
193
194 getyx(obj->obj.win, cur_y, cur_x);
195 obj->old_hscroll = obj->hscroll;
196
197 print_last_page(obj);
198 obj->last_pos = ftell(fp);
199
200 (void) wmove(obj->obj.win, cur_y, cur_x); /* Restore cursor position */
201 wrefresh(obj->obj.win);
202 }
203
204 static bool
handle_input(DIALOG_CALLBACK * cb)205 handle_input(DIALOG_CALLBACK * cb)
206 {
207 MY_OBJ *obj = (MY_OBJ *) cb;
208 FILE *fp = obj->obj.input;
209 struct stat sb;
210
211 if (fstat(fileno(fp), &sb) == 0
212 && sb.st_size != obj->last_pos) {
213 repaint_text(obj);
214 }
215
216 return TRUE;
217 }
218
219 static bool
valid_callback(DIALOG_CALLBACK * cb)220 valid_callback(DIALOG_CALLBACK * cb)
221 {
222 bool valid = FALSE;
223 DIALOG_CALLBACK *p;
224 for (p = dialog_state.getc_callbacks; p != 0; p = p->next) {
225 if (p == cb) {
226 valid = TRUE;
227 break;
228 }
229 }
230 return valid;
231 }
232
233 static bool
handle_my_getc(DIALOG_CALLBACK * cb,int ch,int fkey,int * result)234 handle_my_getc(DIALOG_CALLBACK * cb, int ch, int fkey, int *result)
235 {
236 MY_OBJ *obj = (MY_OBJ *) cb;
237 bool done = FALSE;
238
239 if (!valid_callback(cb))
240 return FALSE;
241
242 if (!fkey && dlg_char_to_button(ch, obj->buttons) == 0) {
243 ch = DLGK_ENTER;
244 fkey = TRUE;
245 }
246
247 if (fkey) {
248 switch (ch) {
249 case DLGK_ENTER:
250 *result = DLG_EXIT_OK;
251 done = TRUE;
252 break;
253 case DLGK_BEGIN: /* Beginning of line */
254 obj->hscroll = 0;
255 break;
256 case DLGK_GRID_LEFT: /* Scroll left */
257 if (obj->hscroll > 0) {
258 obj->hscroll -= 1;
259 }
260 break;
261 case DLGK_GRID_RIGHT: /* Scroll right */
262 if (obj->hscroll < MAX_LEN)
263 obj->hscroll += 1;
264 break;
265 default:
266 if (is_DLGK_MOUSE(ch)) {
267 *result = dlg_ok_buttoncode(ch - M_EVENT);
268 if (*result != DLG_EXIT_ERROR) {
269 done = TRUE;
270 } else {
271 beep();
272 }
273 } else {
274 beep();
275 }
276 break;
277 }
278 if ((obj->hscroll != obj->old_hscroll))
279 repaint_text(obj);
280 } else {
281 switch (ch) {
282 case ERR:
283 clearerr(cb->input);
284 ch = getc(cb->input);
285 (void) ungetc(ch, cb->input);
286 if (ch != EOF) {
287 handle_input(cb);
288 }
289 break;
290 case ESC:
291 done = TRUE;
292 *result = DLG_EXIT_ESC;
293 break;
294 default:
295 beep();
296 break;
297 }
298 }
299
300 return !done;
301 }
302
303 /*
304 * Display text from a file in a dialog box, like in a "tail -f".
305 */
306 int
dialog_tailbox(const char * title,const char * filename,int height,int width,int bg_task)307 dialog_tailbox(const char *title,
308 const char *filename,
309 int height,
310 int width,
311 int bg_task)
312 {
313 /* *INDENT-OFF* */
314 static DLG_KEYS_BINDING binding[] = {
315 HELPKEY_BINDINGS,
316 ENTERKEY_BINDINGS,
317 DLG_KEYS_DATA( DLGK_BEGIN, '0' ),
318 DLG_KEYS_DATA( DLGK_BEGIN, KEY_BEG ),
319 DLG_KEYS_DATA( DLGK_GRID_LEFT, 'H' ),
320 DLG_KEYS_DATA( DLGK_GRID_LEFT, 'h' ),
321 DLG_KEYS_DATA( DLGK_GRID_LEFT, KEY_LEFT ),
322 DLG_KEYS_DATA( DLGK_GRID_RIGHT, 'L' ),
323 DLG_KEYS_DATA( DLGK_GRID_RIGHT, 'l' ),
324 DLG_KEYS_DATA( DLGK_GRID_RIGHT, KEY_RIGHT ),
325 END_KEYS_BINDING
326 };
327 /* *INDENT-ON* */
328
329 #ifdef KEY_RESIZE
330 int old_height = height;
331 int old_width = width;
332 #endif
333 int fkey;
334 int x, y, result = DLG_EXIT_UNKNOWN, thigh;
335 WINDOW *dialog, *text;
336 const char **buttons = 0;
337 MY_OBJ *obj;
338 FILE *fd;
339 int min_width = 12;
340
341 DLG_TRACE(("# tailbox args:\n"));
342 DLG_TRACE2S("title", title);
343 DLG_TRACE2S("filename", filename);
344 DLG_TRACE2N("height", height);
345 DLG_TRACE2N("width", width);
346 DLG_TRACE2N("bg_task", bg_task);
347
348 /* Open input file for reading */
349 if ((fd = fopen(filename, "rb")) == NULL)
350 dlg_exiterr("Can't open input file in dialog_tailbox().");
351
352 #ifdef KEY_RESIZE
353 retry:
354 #endif
355 dlg_auto_sizefile(title, filename, &height, &width, 2, min_width);
356 dlg_print_size(height, width);
357 dlg_ctl_size(height, width);
358
359 x = dlg_box_x_ordinate(width);
360 y = dlg_box_y_ordinate(height);
361 thigh = height - ((2 * MARGIN) + (bg_task ? 0 : 2));
362
363 dialog = dlg_new_window(height, width, y, x);
364
365 dlg_mouse_setbase(x, y);
366
367 /* Create window for text region, used for scrolling text */
368 text = dlg_sub_window(dialog,
369 thigh,
370 width - (2 * MARGIN),
371 y + MARGIN,
372 x + MARGIN);
373
374 dlg_draw_box2(dialog, 0, 0, height, width, dialog_attr, border_attr, border2_attr);
375 dlg_draw_bottom_box2(dialog, border_attr, border2_attr, dialog_attr);
376 dlg_draw_title(dialog, title);
377 dlg_draw_helpline(dialog, FALSE);
378
379 if (!bg_task) {
380 buttons = dlg_exit_label();
381 dlg_button_layout(buttons, &min_width);
382 dlg_draw_buttons(dialog, height - (2 * MARGIN), 0, buttons, FALSE,
383 FALSE, width);
384 }
385
386 (void) wmove(dialog, thigh, (MARGIN + 1));
387 (void) wnoutrefresh(dialog);
388
389 obj = dlg_calloc(MY_OBJ, 1);
390 assert_ptr(obj, "dialog_tailbox");
391
392 obj->obj.input = fd;
393 obj->obj.win = dialog;
394 obj->obj.handle_getc = handle_my_getc;
395 obj->obj.handle_input = bg_task ? handle_input : 0;
396 obj->obj.keep_bg = bg_task && dialog_vars.cant_kill;
397 obj->obj.bg_task = (bool) bg_task;
398 obj->text = text;
399 obj->buttons = buttons;
400 dlg_add_callback(&(obj->obj));
401
402 dlg_register_window(dialog, "tailbox", binding);
403 dlg_register_buttons(dialog, "tailbox", buttons);
404
405 /* Print last page of text */
406 dlg_attr_clear(text, thigh, getmaxx(text), dialog_attr);
407 repaint_text(obj);
408
409 dlg_trace_win(dialog);
410 if (bg_task) {
411 result = DLG_EXIT_OK;
412 } else {
413 int ch;
414 do {
415 ch = dlg_mouse_wgetch(dialog, &fkey);
416 #ifdef KEY_RESIZE
417 if (fkey && ch == KEY_RESIZE) {
418 dlg_will_resize(dialog);
419 /* reset data */
420 height = old_height;
421 width = old_width;
422 /* repaint */
423 _dlg_resize_cleanup(dialog);
424 dlg_button_layout(buttons, &min_width);
425 goto retry;
426 }
427 #endif
428 }
429 while (handle_my_getc(&(obj->obj), ch, fkey, &result));
430 }
431 dlg_mouse_free_regions();
432 return result;
433 }
434