1 /* 2 * $Id: tailbox.c,v 1.68 2012/11/18 15:48:52 tom Exp $ 3 * 4 * tailbox.c -- implements the tail box 5 * 6 * Copyright 2000-2011,2012 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 #ifdef NCURSES_VERSION 92 (void) waddnstr(win, line, MIN((int) strlen(line), width - 2)); 93 #else 94 line[MIN((int) strlen(line), width - 2)] = '\0'; 95 waddstr(win, line); 96 #endif 97 98 getyx(win, y, x); 99 (void) y; 100 /* Clear 'residue' of previous line */ 101 for (i = 0; i < width - x; i++) 102 (void) waddch(win, ' '); 103 } 104 105 /* 106 * Go back 'target' lines in text file. BUFSIZ has to be in 'size_t' range. 107 */ 108 static void 109 last_lines(MY_OBJ * obj, int target) 110 { 111 FILE *fp = obj->obj.input; 112 size_t inx; 113 int count = 0; 114 char buf[BUFSIZ + 1]; 115 size_t size_to_read; 116 size_t size_as_read; 117 long offset = 0; 118 long fpos = 0; 119 120 if (fseek(fp, 0L, SEEK_END) == -1 121 || (fpos = ftell(fp)) < 0) 122 dlg_exiterr("Error moving file pointer in last_lines()."); 123 124 if (fpos != 0) { 125 ++target; 126 for (;;) { 127 if (fpos >= BUFSIZ) { 128 size_to_read = BUFSIZ; 129 } else { 130 size_to_read = (size_t) fpos; 131 } 132 fpos = fpos - (long) size_to_read; 133 if (fseek(fp, fpos, SEEK_SET) == -1) 134 dlg_exiterr("Error moving file pointer in last_lines()."); 135 size_as_read = fread(buf, sizeof(char), size_to_read, fp); 136 if (ferror(fp)) 137 dlg_exiterr("Error reading file in last_lines()."); 138 139 if (size_as_read == 0) { 140 fpos = 0; 141 offset = 0; 142 break; 143 } 144 145 offset += (long) size_as_read; 146 for (inx = size_as_read - 1; inx != 0; --inx) { 147 if (buf[inx] == '\n') { 148 if (++count > target) 149 break; 150 offset = (long) (inx + 1); 151 } 152 } 153 154 if (count > target) { 155 break; 156 } else if (fpos == 0) { 157 offset = 0; 158 break; 159 } 160 } 161 162 if (fseek(fp, fpos + offset, SEEK_SET) == -1) 163 dlg_exiterr("Error moving file pointer in last_lines()."); 164 } 165 } 166 167 /* 168 * Print a new page of text. 169 */ 170 static void 171 print_page(MY_OBJ * obj, int height, int width) 172 { 173 int i; 174 175 for (i = 0; i < height; i++) { 176 print_line(obj, obj->text, i, width); 177 } 178 (void) wnoutrefresh(obj->text); 179 } 180 181 static void 182 print_last_page(MY_OBJ * obj) 183 { 184 int high = getmaxy(obj->obj.win) - (2 * MARGIN + (obj->obj.bg_task ? 1 : 3)); 185 int wide = getmaxx(obj->text); 186 187 last_lines(obj, high); 188 print_page(obj, high, wide); 189 } 190 191 static void 192 repaint_text(MY_OBJ * obj) 193 { 194 FILE *fp = obj->obj.input; 195 int cur_y, cur_x; 196 197 getyx(obj->obj.win, cur_y, cur_x); 198 obj->old_hscroll = obj->hscroll; 199 200 print_last_page(obj); 201 obj->last_pos = ftell(fp); 202 203 (void) wmove(obj->obj.win, cur_y, cur_x); /* Restore cursor position */ 204 wrefresh(obj->obj.win); 205 } 206 207 static bool 208 handle_input(DIALOG_CALLBACK * cb) 209 { 210 MY_OBJ *obj = (MY_OBJ *) cb; 211 FILE *fp = obj->obj.input; 212 struct stat sb; 213 214 if (fstat(fileno(fp), &sb) == 0 215 && sb.st_size != obj->last_pos) { 216 repaint_text(obj); 217 } 218 219 return TRUE; 220 } 221 222 static bool 223 handle_my_getc(DIALOG_CALLBACK * cb, int ch, int fkey, int *result) 224 { 225 MY_OBJ *obj = (MY_OBJ *) cb; 226 bool done = FALSE; 227 228 if (!fkey && dlg_char_to_button(ch, obj->buttons) == 0) { 229 ch = DLGK_ENTER; 230 fkey = TRUE; 231 } 232 233 if (fkey) { 234 switch (ch) { 235 case DLGK_ENTER: 236 *result = DLG_EXIT_OK; 237 done = TRUE; 238 break; 239 case DLGK_BEGIN: /* Beginning of line */ 240 obj->hscroll = 0; 241 break; 242 case DLGK_GRID_LEFT: /* Scroll left */ 243 if (obj->hscroll > 0) { 244 obj->hscroll -= 1; 245 } 246 break; 247 case DLGK_GRID_RIGHT: /* Scroll right */ 248 if (obj->hscroll < MAX_LEN) 249 obj->hscroll += 1; 250 break; 251 default: 252 beep(); 253 break; 254 } 255 if ((obj->hscroll != obj->old_hscroll)) 256 repaint_text(obj); 257 } else { 258 switch (ch) { 259 case ERR: 260 clearerr(cb->input); 261 ch = getc(cb->input); 262 (void) ungetc(ch, cb->input); 263 if (ch != EOF) { 264 handle_input(cb); 265 } 266 break; 267 case ESC: 268 done = TRUE; 269 *result = DLG_EXIT_ESC; 270 break; 271 default: 272 beep(); 273 break; 274 } 275 } 276 277 return !done; 278 } 279 280 /* 281 * Display text from a file in a dialog box, like in a "tail -f". 282 */ 283 int 284 dialog_tailbox(const char *title, const char *file, int height, int width, int bg_task) 285 { 286 /* *INDENT-OFF* */ 287 static DLG_KEYS_BINDING binding[] = { 288 HELPKEY_BINDINGS, 289 ENTERKEY_BINDINGS, 290 DLG_KEYS_DATA( DLGK_BEGIN, '0' ), 291 DLG_KEYS_DATA( DLGK_BEGIN, KEY_BEG ), 292 DLG_KEYS_DATA( DLGK_GRID_LEFT, 'H' ), 293 DLG_KEYS_DATA( DLGK_GRID_LEFT, 'h' ), 294 DLG_KEYS_DATA( DLGK_GRID_LEFT, KEY_LEFT ), 295 DLG_KEYS_DATA( DLGK_GRID_RIGHT, 'L' ), 296 DLG_KEYS_DATA( DLGK_GRID_RIGHT, 'l' ), 297 DLG_KEYS_DATA( DLGK_GRID_RIGHT, KEY_RIGHT ), 298 END_KEYS_BINDING 299 }; 300 /* *INDENT-ON* */ 301 302 #ifdef KEY_RESIZE 303 int old_height = height; 304 int old_width = width; 305 #endif 306 int fkey; 307 int x, y, result, thigh; 308 WINDOW *dialog, *text; 309 const char **buttons = 0; 310 MY_OBJ *obj; 311 FILE *fd; 312 int min_width = 12; 313 314 /* Open input file for reading */ 315 if ((fd = fopen(file, "rb")) == NULL) 316 dlg_exiterr("Can't open input file in dialog_tailbox()."); 317 318 #ifdef KEY_RESIZE 319 retry: 320 #endif 321 dlg_auto_sizefile(title, file, &height, &width, 2, min_width); 322 dlg_print_size(height, width); 323 dlg_ctl_size(height, width); 324 325 x = dlg_box_x_ordinate(width); 326 y = dlg_box_y_ordinate(height); 327 thigh = height - ((2 * MARGIN) + (bg_task ? 0 : 2)); 328 329 dialog = dlg_new_window(height, width, y, x); 330 331 dlg_mouse_setbase(x, y); 332 333 /* Create window for text region, used for scrolling text */ 334 text = dlg_sub_window(dialog, 335 thigh, 336 width - (2 * MARGIN), 337 y + MARGIN, 338 x + MARGIN); 339 340 dlg_draw_box2(dialog, 0, 0, height, width, dialog_attr, border_attr, border2_attr); 341 dlg_draw_bottom_box2(dialog, border_attr, border2_attr, dialog_attr); 342 dlg_draw_title(dialog, title); 343 dlg_draw_helpline(dialog, FALSE); 344 345 if (!bg_task) { 346 buttons = dlg_exit_label(); 347 dlg_button_layout(buttons, &min_width); 348 dlg_draw_buttons(dialog, height - (2 * MARGIN), 0, buttons, FALSE, 349 FALSE, width); 350 } 351 352 (void) wmove(dialog, thigh, (MARGIN + 1)); 353 (void) wnoutrefresh(dialog); 354 355 obj = dlg_calloc(MY_OBJ, 1); 356 assert_ptr(obj, "dialog_tailbox"); 357 358 obj->obj.input = fd; 359 obj->obj.win = dialog; 360 obj->obj.handle_getc = handle_my_getc; 361 obj->obj.handle_input = bg_task ? handle_input : 0; 362 obj->obj.keep_bg = bg_task && dialog_vars.cant_kill; 363 obj->obj.bg_task = bg_task; 364 obj->text = text; 365 obj->buttons = buttons; 366 dlg_add_callback(&(obj->obj)); 367 368 dlg_register_window(dialog, "tailbox", binding); 369 dlg_register_buttons(dialog, "tailbox", buttons); 370 371 /* Print last page of text */ 372 dlg_attr_clear(text, thigh, getmaxx(text), dialog_attr); 373 repaint_text(obj); 374 375 dlg_trace_win(dialog); 376 if (bg_task) { 377 result = DLG_EXIT_OK; 378 } else { 379 int ch; 380 do { 381 ch = dlg_getc(dialog, &fkey); 382 #ifdef KEY_RESIZE 383 if (fkey && ch == KEY_RESIZE) { 384 /* reset data */ 385 height = old_height; 386 width = old_width; 387 /* repaint */ 388 dlg_clear(); 389 dlg_del_window(dialog); 390 refresh(); 391 dlg_mouse_free_regions(); 392 dlg_button_layout(buttons, &min_width); 393 goto retry; 394 } 395 #endif 396 } 397 while (handle_my_getc(&(obj->obj), ch, fkey, &result)); 398 } 399 dlg_mouse_free_regions(); 400 return result; 401 } 402