curses.c

   1 /* curses.c - helper functions related to curses
   2  * Copyright © 2013 Géraud Meyer <graud@gmx.com>
   3  *
   4  * This file is part of ng-jackspa.
   5  *
   6  * ng-jackspa is free software; you can redistribute it and/or modify it under
   7  * the terms of the GNU General Public License version 2 as published by the
   8  * Free Software Foundation.
   9  *
  10  * This program is distributed in the hope that it will be useful, but WITHOUT
  11  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  12  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  13  * more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with ng-jackspa.  If not, see <http://www.gnu.org/licenses/>.
  17  */
  18
  19 #define CTRL(key) ((key)-64)
  20
  21 /* Read user text input from a curses window with line editing keys.
  22  * The result is obtained from the window itself, not from the keyboard; a
  23  * space marks the end of the input; if the text contains a ^O character, the
  24  * input is cancelled (as soon as the ^O is processed).
  25  * The terminal must not echo, and it should be in cbreak mode (rather than in
  26  * line editing mode, aka cooked mode); a pseudo line editing terminal mode is
  27  * emulated, with additional emacs-like edit/move keys.
  28  */
  29 int wtextentry(WINDOW *win, char *result, size_t size)
  30 {
  31         short s; /* state varibale */
  32         int k; /* keyboard input */
  33         char c; /* input char */
  34         int row, col;
  35
  36         wclear(win);
  37
  38         for (s = 1; s > 0; )
  39                 switch(k = wgetch(win)) {
  40                 case KEY_CANCEL:
  41                 case CTRL('O'): /* cancel */
  42                 case '\e':
  43                         s = 2;
  44                         ungetch('\n');
  45                         break;
  46                 case KEY_ENTER:
  47                 case '\n': /* eof */
  48                         if (s != 1) s = -1;
  49                         else s = 0;
  50                         break;
  51                 case KEY_BACKSPACE: /* erase */
  52                 case '\b':
  53                         getyx(win, row, col), wmove(win, row, col-1), wdelch(win);
  54                         break;
  55                 case KEY_DC: /* delete */
  56                 case CTRL('D'):
  57                         wdelch(win);
  58                         break;
  59                 case CTRL('U'): /* kill */
  60                         wmove(win, 0, 0), wclrtoeol(win);
  61                         break;
  62                 case CTRL('K'):
  63                         wclrtoeol(win);
  64                         break;
  65                 case KEY_UP: /* default/previous input field */
  66                 case CTRL('P'):
  67                         wmove(win, 0, 0), wclrtoeol(win);
  68                         wmove(win, 0, 0), waddnstr(win, result, size);
  69                         break;
  70                 case CTRL('B'):
  71                 case KEY_LEFT:
  72                         getyx(win, row, col), wmove(win, row, col-1);
  73                         break;
  74                 case CTRL('F'):
  75                 case KEY_RIGHT:
  76                         getyx(win, row, col);
  77                         if (col+1 < size) wmove(win, row, col+1);
  78                         break;
  79                 case KEY_HOME:
  80                 case CTRL('A'):
  81                         wmove(win, 0, 0);
  82                         break;
  83                 case KEY_END:
  84                 case CTRL('E'):
  85                         getyx(win, row, col);
  86                         for (; col < size-1 && (c = mvwinch(win, row, col)&A_CHARTEXT) != ' '; col++);
  87                         break;
  88                 case ERR:
  89                         break;
  90                 default:
  91                         getyx(win, row, col);
  92                         waddch(win, k);
  93                         break;
  94                 }
  95
  96         if (s < 0)
  97                 return (result[0] = '\0', 1);
  98         else {
  99                 for (col = 0; col < size-1 && (c = mvwinch(win, 0, col)&A_CHARTEXT) != ' '; col++)
 100                         result[col] = c;
 101                 result[col] = '\0';
 102         }
 103
 104         return 0;
 105 }