gpxe/src/hci/mucurses/widgets/editbox.c

   1 /*
   2  * Copyright (C) 2006 Michael Brown <mbrown@fensystems.co.uk>.
   3  *
   4  * This program is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU General Public License as
   6  * published by the Free Software Foundation; either version 2 of the
   7  * License, or any later version.
   8  *
   9  * This program is distributed in the hope that it will be useful, but
  10  * WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  * General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program; if not, write to the Free Software
  16  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  17  */
  18
  19 #include <string.h>
  20 #include <assert.h>
  21 #include <gpxe/editbox.h>
  22
  23 /** @file
  24  *
  25  * Editable text box widget
  26  *
  27  */
  28
  29 #define EDITBOX_MIN_CHARS 3
  30
  31 /**
  32  * Initialise text box widget
  33  *
  34  * @v box               Editable text box widget
  35  * @v buf               Text buffer
  36  * @v len               Size of text buffer
  37  * @v win               Containing window
  38  * @v row               Row
  39  * @v col               Starting column
  40  * @v width             Width
  41  *
  42  */
  43 void init_editbox ( struct edit_box *box, char *buf, size_t len,
  44                     WINDOW *win, unsigned int row, unsigned int col,
  45                     unsigned int width ) {
  46         memset ( box, 0, sizeof ( *box ) );
  47         box->string.buf = buf;
  48         box->string.len = len;
  49         box->string.cursor = strlen ( buf );
  50         box->win = ( win ? win : stdscr );
  51         box->row = row;
  52         box->col = col;
  53         box->width = width;
  54 }
  55
  56 /**
  57  * Draw text box widget
  58  *
  59  * @v box               Editable text box widget
  60  *
  61  */
  62 void draw_editbox ( struct edit_box *box ) {
  63         size_t width = box->width;
  64         char buf[ width + 1 ];
  65         signed int cursor_offset, underflow, overflow, first;
  66         size_t len;
  67
  68         /* Adjust starting offset so that cursor remains within box */
  69         cursor_offset = ( box->string.cursor - box->first );
  70         underflow = ( EDITBOX_MIN_CHARS - cursor_offset );
  71         overflow = ( cursor_offset - ( width - 1 ) );
  72         first = box->first;
  73         if ( underflow > 0 ) {
  74                 first -= underflow;
  75                 if ( first < 0 )
  76                         first = 0;
  77         } else if ( overflow > 0 ) {
  78                 first += overflow;
  79         }
  80         box->first = first;
  81         cursor_offset = ( box->string.cursor - first );
  82
  83         /* Construct underscore-padded string portion */
  84         memset ( buf, '_', width );
  85         buf[width] = '\0';
  86         len = ( strlen ( box->string.buf ) - first );
  87         if ( len > width )
  88                 len = width;
  89         memcpy ( buf, ( box->string.buf + first ), len );
  90
  91         /* Print box content and move cursor */
  92         if ( ! box->win )
  93                 box->win = stdscr;
  94         mvwprintw ( box->win, box->row, box->col, "%s", buf );
  95         wmove ( box->win, box->row, ( box->col + cursor_offset ) );
  96 }