1 /* 2 * $Id: tailbox.c,v 1.72 2018/06/19 22:57:01 tom Exp $ 3 * 4 * tailbox.c -- implements the tail box 5 * 6 * Copyright 2000-2012,2018 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 size_t inx; 108 int count = 0; 109 char buf[BUFSIZ + 1]; 110 size_t size_to_read; 111 size_t size_as_read; 112 long offset = 0; 113 long fpos = 0; 114 115 if (fseek(fp, 0L, SEEK_END) == -1 116 || (fpos = ftell(fp)) < 0) 117 dlg_exiterr("Error moving file pointer in last_lines()."); 118 119 if (fpos != 0) { 120 ++target; 121 for (;;) { 122 if (fpos >= BUFSIZ) { 123 size_to_read = BUFSIZ; 124 } else { 125 size_to_read = (size_t) fpos; 126 } 127 fpos = fpos - (long) size_to_read; 128 if (fseek(fp, fpos, SEEK_SET) == -1) 129 dlg_exiterr("Error moving file pointer in last_lines()."); 130 size_as_read = fread(buf, sizeof(char), size_to_read, fp); 131 if (ferror(fp)) 132 dlg_exiterr("Error reading file in last_lines()."); 133 134 if (size_as_read == 0) { 135 fpos = 0; 136 offset = 0; 137 break; 138 } 139 140 offset += (long) size_as_read; 141 for (inx = size_as_read - 1; inx != 0; --inx) { 142 if (buf[inx] == '\n') { 143 if (++count > target) 144 break; 145 offset = (long) (inx + 1); 146 } 147 } 148 149 if (count > target) { 150 break; 151 } else if (fpos == 0) { 152 offset = 0; 153 break; 154 } 155 } 156 157 if (fseek(fp, fpos + offset, SEEK_SET) == -1) 158 dlg_exiterr("Error moving file pointer in last_lines()."); 159 } 160 } 161 162 /* 163 * Print a new page of text. 164 */ 165 static void 166 print_page(MY_OBJ * obj, int height, int width) 167 { 168 int i; 169 170 for (i = 0; i < height; i++) { 171 print_line(obj, obj->text, i, width); 172 } 173 (void) wnoutrefresh(obj->text); 174 } 175 176 static void 177 print_last_page(MY_OBJ * obj) 178 { 179 int high = getmaxy(obj->obj.win) - (2 * MARGIN + (obj->obj.bg_task ? 1 : 3)); 180 int wide = getmaxx(obj->text); 181 182 last_lines(obj, high); 183 print_page(obj, high, wide); 184 } 185 186 static void 187 repaint_text(MY_OBJ * obj) 188 { 189 FILE *fp = obj->obj.input; 190 int cur_y, cur_x; 191 192 getyx(obj->obj.win, cur_y, cur_x); 193 obj->old_hscroll = obj->hscroll; 194 195 print_last_page(obj); 196 obj->last_pos = ftell(fp); 197 198 (void) wmove(obj->obj.win, cur_y, cur_x); /* Restore cursor position */ 199 wrefresh(obj->obj.win); 200 } 201 202 static bool 203 handle_input(DIALOG_CALLBACK * cb) 204 { 205 MY_OBJ *obj = (MY_OBJ *) cb; 206 FILE *fp = obj->obj.input; 207 struct stat sb; 208 209 if (fstat(fileno(fp), &sb) == 0 210 && sb.st_size != obj->last_pos) { 211 repaint_text(obj); 212 } 213 214 return TRUE; 215 } 216 217 static bool 218 valid_callback(DIALOG_CALLBACK * cb) 219 { 220 bool valid = FALSE; 221 DIALOG_CALLBACK *p; 222 for (p = dialog_state.getc_callbacks; p != 0; p = p->next) { 223 if (p == cb) { 224 valid = TRUE; 225 break; 226 } 227 } 228 return valid; 229 } 230 231 static bool 232 handle_my_getc(DIALOG_CALLBACK * cb, int ch, int fkey, int *result) 233 { 234 MY_OBJ *obj = (MY_OBJ *) cb; 235 bool done = FALSE; 236 237 if (!valid_callback(cb)) 238 return FALSE; 239 240 if (!fkey && dlg_char_to_button(ch, obj->buttons) == 0) { 241 ch = DLGK_ENTER; 242 fkey = TRUE; 243 } 244 245 if (fkey) { 246 switch (ch) { 247 case DLGK_ENTER: 248 *result = DLG_EXIT_OK; 249 done = TRUE; 250 break; 251 case DLGK_BEGIN: /* Beginning of line */ 252 obj->hscroll = 0; 253 break; 254 case DLGK_GRID_LEFT: /* Scroll left */ 255 if (obj->hscroll > 0) { 256 obj->hscroll -= 1; 257 } 258 break; 259 case DLGK_GRID_RIGHT: /* Scroll right */ 260 if (obj->hscroll < MAX_LEN) 261 obj->hscroll += 1; 262 break; 263 default: 264 beep(); 265 break; 266 } 267 if ((obj->hscroll != obj->old_hscroll)) 268 repaint_text(obj); 269 } else { 270 switch (ch) { 271 case ERR: 272 clearerr(cb->input); 273 ch = getc(cb->input); 274 (void) ungetc(ch, cb->input); 275 if (ch != EOF) { 276 handle_input(cb); 277 } 278 break; 279 case ESC: 280 done = TRUE; 281 *result = DLG_EXIT_ESC; 282 break; 283 default: 284 beep(); 285 break; 286 } 287 } 288 289 return !done; 290 } 291 292 /* 293 * Display text from a file in a dialog box, like in a "tail -f". 294 */ 295 int 296 dialog_tailbox(const char *title, 297 const char *filename, 298 int height, 299 int width, 300 int bg_task) 301 { 302 /* *INDENT-OFF* */ 303 static DLG_KEYS_BINDING binding[] = { 304 HELPKEY_BINDINGS, 305 ENTERKEY_BINDINGS, 306 DLG_KEYS_DATA( DLGK_BEGIN, '0' ), 307 DLG_KEYS_DATA( DLGK_BEGIN, KEY_BEG ), 308 DLG_KEYS_DATA( DLGK_GRID_LEFT, 'H' ), 309 DLG_KEYS_DATA( DLGK_GRID_LEFT, 'h' ), 310 DLG_KEYS_DATA( DLGK_GRID_LEFT, KEY_LEFT ), 311 DLG_KEYS_DATA( DLGK_GRID_RIGHT, 'L' ), 312 DLG_KEYS_DATA( DLGK_GRID_RIGHT, 'l' ), 313 DLG_KEYS_DATA( DLGK_GRID_RIGHT, KEY_RIGHT ), 314 END_KEYS_BINDING 315 }; 316 /* *INDENT-ON* */ 317 318 #ifdef KEY_RESIZE 319 int old_height = height; 320 int old_width = width; 321 #endif 322 int fkey; 323 int x, y, result, thigh; 324 WINDOW *dialog, *text; 325 const char **buttons = 0; 326 MY_OBJ *obj; 327 FILE *fd; 328 int min_width = 12; 329 330 DLG_TRACE(("# tailbox args:\n")); 331 DLG_TRACE2S("title", title); 332 DLG_TRACE2S("filename", filename); 333 DLG_TRACE2N("height", height); 334 DLG_TRACE2N("width", width); 335 DLG_TRACE2N("bg_task", bg_task); 336 337 /* Open input file for reading */ 338 if ((fd = fopen(filename, "rb")) == NULL) 339 dlg_exiterr("Can't open input file in dialog_tailbox()."); 340 341 #ifdef KEY_RESIZE 342 retry: 343 #endif 344 dlg_auto_sizefile(title, filename, &height, &width, 2, min_width); 345 dlg_print_size(height, width); 346 dlg_ctl_size(height, width); 347 348 x = dlg_box_x_ordinate(width); 349 y = dlg_box_y_ordinate(height); 350 thigh = height - ((2 * MARGIN) + (bg_task ? 0 : 2)); 351 352 dialog = dlg_new_window(height, width, y, x); 353 354 dlg_mouse_setbase(x, y); 355 356 /* Create window for text region, used for scrolling text */ 357 text = dlg_sub_window(dialog, 358 thigh, 359 width - (2 * MARGIN), 360 y + MARGIN, 361 x + MARGIN); 362 363 dlg_draw_box2(dialog, 0, 0, height, width, dialog_attr, border_attr, border2_attr); 364 dlg_draw_bottom_box2(dialog, border_attr, border2_attr, dialog_attr); 365 dlg_draw_title(dialog, title); 366 dlg_draw_helpline(dialog, FALSE); 367 368 if (!bg_task) { 369 buttons = dlg_exit_label(); 370 dlg_button_layout(buttons, &min_width); 371 dlg_draw_buttons(dialog, height - (2 * MARGIN), 0, buttons, FALSE, 372 FALSE, width); 373 } 374 375 (void) wmove(dialog, thigh, (MARGIN + 1)); 376 (void) wnoutrefresh(dialog); 377 378 obj = dlg_calloc(MY_OBJ, 1); 379 assert_ptr(obj, "dialog_tailbox"); 380 381 obj->obj.input = fd; 382 obj->obj.win = dialog; 383 obj->obj.handle_getc = handle_my_getc; 384 obj->obj.handle_input = bg_task ? handle_input : 0; 385 obj->obj.keep_bg = bg_task && dialog_vars.cant_kill; 386 obj->obj.bg_task = bg_task; 387 obj->text = text; 388 obj->buttons = buttons; 389 dlg_add_callback(&(obj->obj)); 390 391 dlg_register_window(dialog, "tailbox", binding); 392 dlg_register_buttons(dialog, "tailbox", buttons); 393 394 /* Print last page of text */ 395 dlg_attr_clear(text, thigh, getmaxx(text), dialog_attr); 396 repaint_text(obj); 397 398 dlg_trace_win(dialog); 399 if (bg_task) { 400 result = DLG_EXIT_OK; 401 } else { 402 int ch; 403 do { 404 ch = dlg_getc(dialog, &fkey); 405 #ifdef KEY_RESIZE 406 if (fkey && ch == KEY_RESIZE) { 407 dlg_will_resize(dialog); 408 /* reset data */ 409 height = old_height; 410 width = old_width; 411 /* repaint */ 412 dlg_clear(); 413 dlg_del_window(dialog); 414 refresh(); 415 dlg_mouse_free_regions(); 416 dlg_button_layout(buttons, &min_width); 417 goto retry; 418 } 419 #endif 420 } 421 while (handle_my_getc(&(obj->obj), ch, fkey, &result)); 422 } 423 dlg_mouse_free_regions(); 424 return result; 425 } 426