1 /* 2 * $Id: tailbox.c,v 1.78 2020/03/27 19:31:03 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 * 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 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 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 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 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 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 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 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 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 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, 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