frm_data.c revision 1.6 
1/*	$OpenBSD: frm_data.c,v 1.6 2001/01/22 18:02:14 millert Exp $	*/
2
3/****************************************************************************
4 * Copyright (c) 1998,2000 Free Software Foundation, Inc.                   *
5 *                                                                          *
6 * Permission is hereby granted, free of charge, to any person obtaining a  *
7 * copy of this software and associated documentation files (the            *
8 * "Software"), to deal in the Software without restriction, including      *
9 * without limitation the rights to use, copy, modify, merge, publish,      *
10 * distribute, distribute with modifications, sublicense, and/or sell       *
11 * copies of the Software, and to permit persons to whom the Software is    *
12 * furnished to do so, subject to the following conditions:                 *
13 *                                                                          *
14 * The above copyright notice and this permission notice shall be included  *
15 * in all copies or substantial portions of the Software.                   *
16 *                                                                          *
17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS  *
18 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF               *
19 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.   *
20 * IN NO EVENT SHALL THE ABOVE COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,   *
21 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR    *
22 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR    *
23 * THE USE OR OTHER DEALINGS IN THE SOFTWARE.                               *
24 *                                                                          *
25 * Except as contained in this notice, the name(s) of the above copyright   *
26 * holders shall not be used in advertising or otherwise to promote the     *
27 * sale, use or other dealings in this Software without prior written       *
28 * authorization.                                                           *
29 ****************************************************************************/
30
31/****************************************************************************
32 *   Author: Juergen Pfeifer <juergen.pfeifer@gmx.net> 1995,1997            *
33 ****************************************************************************/
34
35#include "form.priv.h"
36
37MODULE_ID("$From: frm_data.c,v 1.7 2000/12/10 02:09:38 tom Exp $")
38
39/*---------------------------------------------------------------------------
40|   Facility      :  libnform
41|   Function      :  bool data_behind(const FORM *form)
42|
43|   Description   :  Check for off-screen data behind. This is nearly trivial
44|                    becose the begin of a field is fixed.
45|
46|   Return Values :  TRUE   - there are off-screen data behind
47|                    FALSE  - there are no off-screen data behind
48+--------------------------------------------------------------------------*/
49NCURSES_EXPORT(bool)
50data_behind (const FORM *form)
51{
52  bool result = FALSE;
53
54  if (form && (form->status & _POSTED) && form->current)
55    {
56      FIELD *field;
57
58      field = form->current;
59      if (!Single_Line_Field(field))
60	{
61	  result = (form->toprow==0) ? FALSE : TRUE;
62	}
63      else
64	{
65	  result = (form->begincol==0) ? FALSE : TRUE;
66	}
67    }
68  return(result);
69}
70
71/*---------------------------------------------------------------------------
72|   Facility      :  libnform
73|   Function      :  static char * After_Last_Non_Pad_Position(
74|                                    char *buffer,
75|                                    int len,
76|                                    int pad)
77|
78|   Description   :  Find the last position in the buffer that doesn't
79|                    contain a padding character.
80|
81|   Return Values :  The pointer to this position
82+--------------------------------------------------------------------------*/
83INLINE
84static char * After_Last_Non_Pad_Position(char *buffer, int len, int pad)
85{
86  char *end = buffer + len;
87
88  assert(buffer && len>=0);
89  while ( (buffer < end) && (*(end-1)==pad) )
90    end--;
91
92  return end;
93}
94
95#define SMALL_BUFFER_SIZE (80)
96
97/*---------------------------------------------------------------------------
98|   Facility      :  libnform
99|   Function      :  bool data_ahead(const FORM *form)
100|
101|   Description   :  Check for off-screen data ahead. This is more difficult
102|                    because a dynamic field has a variable end.
103|
104|   Return Values :  TRUE   - there are off-screen data ahead
105|                    FALSE  - there are no off-screen data ahead
106+--------------------------------------------------------------------------*/
107NCURSES_EXPORT(bool)
108data_ahead (const FORM *form)
109{
110  bool result = FALSE;
111
112  if (form && (form->status & _POSTED) && form->current)
113    {
114      static char buffer[SMALL_BUFFER_SIZE + 1];
115      FIELD *field;
116      bool large_buffer;
117      bool cursor_moved = FALSE;
118      char *bp;
119      char *found_content;
120      int pos;
121
122      field = form->current;
123      assert(form->w);
124
125      large_buffer = (field->cols > SMALL_BUFFER_SIZE);
126      if (large_buffer)
127	bp = (char *)malloc((size_t)(field->cols) + 1);
128      else
129	bp = buffer;
130
131      assert(bp);
132
133      if (Single_Line_Field(field))
134	{
135	  int check_len;
136
137	  pos = form->begincol + field->cols;
138	  while (pos < field->dcols)
139	    {
140	      check_len = field->dcols - pos;
141	      if ( check_len >= field->cols )
142		check_len = field->cols;
143	      cursor_moved = TRUE;
144	      wmove(form->w,0,pos);
145	      winnstr(form->w,bp,check_len);
146	      found_content =
147		After_Last_Non_Pad_Position(bp,check_len,field->pad);
148	      if (found_content==bp)
149		  pos += field->cols;
150	      else
151		{
152		  result = TRUE;
153		  break;
154		}
155	    }
156	}
157      else
158	{
159	  pos = form->toprow + field->rows;
160	  while (pos < field->drows)
161	    {
162	      cursor_moved = TRUE;
163	      wmove(form->w,pos,0);
164	      pos++;
165	      winnstr(form->w,bp,field->cols);
166	      found_content =
167		After_Last_Non_Pad_Position(bp,field->cols,field->pad);
168	      if (found_content!=bp)
169		{
170		  result = TRUE;
171		  break;
172		}
173	    }
174	}
175
176      if (large_buffer)
177	free(bp);
178
179      if (cursor_moved)
180	wmove(form->w,form->currow,form->curcol);
181    }
182  return(result);
183}
184
185/* frm_data.c ends here */
186