1 /* 2 * $Id: tailbox.c,v 1.63 2011/06/27 08:19:43 tom Exp $ 3 * 4 * tailbox.c -- implements the tail box 5 * 6 * Copyright 2000-2010,2011 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 + 1]; 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 /* Clear 'residue' of previous line */ 100 for (i = 0; i < width - x; i++) 101 (void) waddch(win, ' '); 102 } 103 104 /* 105 * Go back 'target' lines in text file. BUFSIZ has to be in 'size_t' range. 106 */ 107 static void 108 last_lines(MY_OBJ * obj, int target) 109 { 110 FILE *fp = obj->obj.input; 111 size_t inx; 112 int count = 0; 113 char buf[BUFSIZ + 1]; 114 size_t size_to_read; 115 size_t size_as_read; 116 long offset = 0; 117 long fpos = 0; 118 119 if (fseek(fp, 0L, SEEK_END) == -1 120 || (fpos = ftell(fp)) < 0) 121 dlg_exiterr("Error moving file pointer in last_lines()."); 122 123 if (fpos != 0) { 124 ++target; 125 for (;;) { 126 if (fpos >= BUFSIZ) { 127 size_to_read = BUFSIZ; 128 } else { 129 size_to_read = (size_t) fpos; 130 } 131 fpos = fpos - (long) size_to_read; 132 if (fseek(fp, fpos, SEEK_SET) == -1) 133 dlg_exiterr("Error moving file pointer in last_lines()."); 134 size_as_read = fread(buf, sizeof(char), size_to_read, fp); 135 if (ferror(fp)) 136 dlg_exiterr("Error reading file in last_lines()."); 137 138 if (size_as_read == 0) { 139 fpos = 0; 140 offset = 0; 141 break; 142 } 143 144 offset += (long) size_as_read; 145 for (inx = size_as_read - 1; inx != 0; --inx) { 146 if (buf[inx] == '\n') { 147 if (++count > target) 148 break; 149 offset = (long) (inx + 1); 150 } 151 } 152 153 if (count > target) { 154 break; 155 } else if (fpos == 0) { 156 offset = 0; 157 break; 158 } 159 } 160 161 if (fseek(fp, fpos + offset, SEEK_SET) == -1) 162 dlg_exiterr("Error moving file pointer in last_lines()."); 163 } 164 } 165 166 /* 167 * Print a new page of text. 168 */ 169 static void 170 print_page(MY_OBJ * obj, int height, int width) 171 { 172 int i; 173 174 for (i = 0; i < height; i++) { 175 print_line(obj, obj->text, i, width); 176 } 177 (void) wnoutrefresh(obj->text); 178 } 179 180 static void 181 print_last_page(MY_OBJ * obj) 182 { 183 int high = getmaxy(obj->obj.win) - (2 * MARGIN + (obj->obj.bg_task ? 1 : 3)); 184 int wide = getmaxx(obj->text); 185 186 last_lines(obj, high); 187 print_page(obj, high, wide); 188 } 189 190 static void 191 repaint_text(MY_OBJ * obj) 192 { 193 FILE *fp = obj->obj.input; 194 int cur_y, cur_x; 195 196 getyx(obj->obj.win, cur_y, cur_x); 197 obj->old_hscroll = obj->hscroll; 198 199 print_last_page(obj); 200 obj->last_pos = ftell(fp); 201 202 (void) wmove(obj->obj.win, cur_y, cur_x); /* Restore cursor position */ 203 wrefresh(obj->obj.win); 204 } 205 206 static bool 207 handle_input(DIALOG_CALLBACK * cb) 208 { 209 MY_OBJ *obj = (MY_OBJ *) cb; 210 FILE *fp = obj->obj.input; 211 struct stat sb; 212 213 if (fstat(fileno(fp), &sb) == 0 214 && sb.st_size != obj->last_pos) { 215 repaint_text(obj); 216 } 217 218 return TRUE; 219 } 220 221 static bool 222 handle_my_getc(DIALOG_CALLBACK * cb, int ch, int fkey, int *result) 223 { 224 MY_OBJ *obj = (MY_OBJ *) cb; 225 bool done = FALSE; 226 227 if (!fkey && dlg_char_to_button(ch, obj->buttons) == 0) { 228 ch = DLGK_ENTER; 229 fkey = TRUE; 230 } 231 232 if (fkey) { 233 switch (ch) { 234 case DLGK_ENTER: 235 *result = DLG_EXIT_OK; 236 done = TRUE; 237 break; 238 case DLGK_BEGIN: /* Beginning of line */ 239 obj->hscroll = 0; 240 break; 241 case DLGK_GRID_LEFT: /* Scroll left */ 242 if (obj->hscroll > 0) { 243 obj->hscroll -= 1; 244 } 245 break; 246 case DLGK_GRID_RIGHT: /* Scroll right */ 247 if (obj->hscroll < MAX_LEN) 248 obj->hscroll += 1; 249 break; 250 default: 251 beep(); 252 break; 253 } 254 if ((obj->hscroll != obj->old_hscroll)) 255 repaint_text(obj); 256 } else { 257 switch (ch) { 258 case ERR: 259 clearerr(cb->input); 260 ch = getc(cb->input); 261 (void) ungetc(ch, cb->input); 262 if (ch != EOF) { 263 handle_input(cb); 264 } 265 break; 266 case ESC: 267 done = TRUE; 268 *result = DLG_EXIT_ESC; 269 break; 270 default: 271 beep(); 272 break; 273 } 274 } 275 276 return !done; 277 } 278 279 /* 280 * Display text from a file in a dialog box, like in a "tail -f". 281 */ 282 int 283 dialog_tailbox(const char *title, const char *file, int height, int width, int bg_task) 284 { 285 /* *INDENT-OFF* */ 286 static DLG_KEYS_BINDING binding[] = { 287 HELPKEY_BINDINGS, 288 ENTERKEY_BINDINGS, 289 DLG_KEYS_DATA( DLGK_BEGIN, '0' ), 290 DLG_KEYS_DATA( DLGK_BEGIN, KEY_BEG ), 291 DLG_KEYS_DATA( DLGK_GRID_LEFT, 'H' ), 292 DLG_KEYS_DATA( DLGK_GRID_LEFT, 'h' ), 293 DLG_KEYS_DATA( DLGK_GRID_LEFT, KEY_LEFT ), 294 DLG_KEYS_DATA( DLGK_GRID_RIGHT, 'L' ), 295 DLG_KEYS_DATA( DLGK_GRID_RIGHT, 'l' ), 296 DLG_KEYS_DATA( DLGK_GRID_RIGHT, KEY_RIGHT ), 297 END_KEYS_BINDING 298 }; 299 /* *INDENT-ON* */ 300 301 #ifdef KEY_RESIZE 302 int old_height = height; 303 int old_width = width; 304 #endif 305 int fkey; 306 int x, y, result, thigh; 307 WINDOW *dialog, *text; 308 const char **buttons = 0; 309 MY_OBJ *obj; 310 FILE *fd; 311 int min_width = 12; 312 313 /* Open input file for reading */ 314 if ((fd = fopen(file, "rb")) == NULL) 315 dlg_exiterr("Can't open input file in dialog_tailbox()."); 316 317 #ifdef KEY_RESIZE 318 retry: 319 #endif 320 dlg_auto_sizefile(title, file, &height, &width, 2, min_width); 321 dlg_print_size(height, width); 322 dlg_ctl_size(height, width); 323 324 x = dlg_box_x_ordinate(width); 325 y = dlg_box_y_ordinate(height); 326 thigh = height - ((2 * MARGIN) + (bg_task ? 0 : 2)); 327 328 dialog = dlg_new_window(height, width, y, x); 329 330 dlg_mouse_setbase(x, y); 331 332 /* Create window for text region, used for scrolling text */ 333 text = dlg_sub_window(dialog, 334 thigh, 335 width - (2 * MARGIN), 336 y + MARGIN, 337 x + MARGIN); 338 339 dlg_draw_box(dialog, 0, 0, height, width, dialog_attr, border_attr); 340 dlg_draw_bottom_box(dialog); 341 dlg_draw_title(dialog, title); 342 dlg_draw_helpline(dialog, FALSE); 343 344 if (!bg_task) { 345 buttons = dlg_exit_label(); 346 dlg_button_layout(buttons, &min_width); 347 dlg_draw_buttons(dialog, height - (2 * MARGIN), 0, buttons, FALSE, 348 FALSE, width); 349 } 350 351 (void) wmove(dialog, thigh, (MARGIN + 1)); 352 (void) wnoutrefresh(dialog); 353 354 obj = dlg_calloc(MY_OBJ, 1); 355 assert_ptr(obj, "dialog_tailbox"); 356 357 obj->obj.input = fd; 358 obj->obj.win = dialog; 359 obj->obj.handle_getc = handle_my_getc; 360 obj->obj.handle_input = bg_task ? handle_input : 0; 361 obj->obj.keep_bg = bg_task && dialog_vars.cant_kill; 362 obj->obj.bg_task = bg_task; 363 obj->text = text; 364 obj->buttons = buttons; 365 dlg_add_callback(&(obj->obj)); 366 367 dlg_register_window(dialog, "tailbox", binding); 368 dlg_register_buttons(dialog, "tailbox", buttons); 369 370 /* Print last page of text */ 371 dlg_attr_clear(text, thigh, getmaxx(text), dialog_attr); 372 repaint_text(obj); 373 374 if (bg_task) { 375 result = DLG_EXIT_OK; 376 } else { 377 int ch; 378 do { 379 ch = dlg_getc(dialog, &fkey); 380 #ifdef KEY_RESIZE 381 if (fkey && ch == KEY_RESIZE) { 382 /* reset data */ 383 height = old_height; 384 width = old_width; 385 /* repaint */ 386 dlg_clear(); 387 dlg_del_window(dialog); 388 refresh(); 389 dlg_mouse_free_regions(); 390 dlg_button_layout(buttons, &min_width); 391 goto retry; 392 } 393 #endif 394 } 395 while (handle_my_getc(&(obj->obj), ch, fkey, &result)); 396 } 397 dlg_mouse_free_regions(); 398 return result; 399 } 400