form/frm_data.c

   1 /****************************************************************************
   2  * Copyright (c) 1998 Free Software Foundation, Inc.                        *
   3  *                                                                          *
   4  * Permission is hereby granted, free of charge, to any person obtaining a  *
   5  * copy of this software and associated documentation files (the            *
   6  * "Software"), to deal in the Software without restriction, including      *
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   8  * distribute, distribute with modifications, sublicense, and/or sell       *
   9  * copies of the Software, and to permit persons to whom the Software is    *
  10  * furnished to do so, subject to the following conditions:                 *
  11  *                                                                          *
  12  * The above copyright notice and this permission notice shall be included  *
  13  * in all copies or substantial portions of the Software.                   *
  14  *                                                                          *
  15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS  *
  16  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF               *
  17  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.   *
  18  * IN NO EVENT SHALL THE ABOVE COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,   *
  19  * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR    *
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  21  * THE USE OR OTHER DEALINGS IN THE SOFTWARE.                               *
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  23  * Except as contained in this notice, the name(s) of the above copyright   *
  24  * holders shall not be used in advertising or otherwise to promote the     *
  25  * sale, use or other dealings in this Software without prior written       *
  26  * authorization.                                                           *
  27  ****************************************************************************/
  28
  29 /****************************************************************************
  30  *   Author: Juergen Pfeifer <Juergen.Pfeifer@T-Online.de> 1995,1997        *
  31  ****************************************************************************/
  32
  33 #include "form.priv.h"
  34
  35 MODULE_ID("$Id: frm_data.c,v 1.4 1998/02/11 12:13:42 tom Exp $")
  36
  37 /*---------------------------------------------------------------------------
  38 |   Facility      :  libnform
  39 |   Function      :  bool data_behind(const FORM *form)
  40 |
  41 |   Description   :  Check for off-screen data behind. This is nearly trivial
  42 |                    becose the begin of a field is fixed.
  43 |
  44 |   Return Values :  TRUE   - there are off-screen data behind
  45 |                    FALSE  - there are no off-screen data behind
  46 +--------------------------------------------------------------------------*/
  47 bool data_behind(const FORM *form)
  48 {
  49   bool result = FALSE;
  50
  51   if (form && (form->status & _POSTED) && form->current)
  52     {
  53       FIELD *field;
  54
  55       field = form->current;
  56       if (!Single_Line_Field(field))
  57         {
  58           result = (form->toprow==0) ? FALSE : TRUE;
  59         }
  60       else
  61         {
  62           result = (form->begincol==0) ? FALSE : TRUE;
  63         }
  64     }
  65   return(result);
  66 }
  67
  68 /*---------------------------------------------------------------------------
  69 |   Facility      :  libnform
  70 |   Function      :  static char * After_Last_Non_Pad_Position(
  71 |                                    char *buffer,
  72 |                                    int len,
  73 |                                    int pad)
  74 |
  75 |   Description   :  Find the last position in the buffer that doesn't
  76 |                    contain a padding character.
  77 |
  78 |   Return Values :  The pointer to this position
  79 +--------------------------------------------------------------------------*/
  80 INLINE
  81 static char * After_Last_Non_Pad_Position(char *buffer, int len, int pad)
  82 {
  83   char *end = buffer + len;
  84
  85   assert(buffer && len>=0);
  86   while ( (buffer < end) && (*(end-1)==pad) )
  87     end--;
  88
  89   return end;
  90 }
  91
  92 #define SMALL_BUFFER_SIZE (80)
  93
  94 /*---------------------------------------------------------------------------
  95 |   Facility      :  libnform
  96 |   Function      :  bool data_ahead(const FORM *form)
  97 |
  98 |   Description   :  Check for off-screen data ahead. This is more difficult
  99 |                    because a dynamic field has a variable end.
 100 |
 101 |   Return Values :  TRUE   - there are off-screen data ahead
 102 |                    FALSE  - there are no off-screen data ahead
 103 +--------------------------------------------------------------------------*/
 104 bool data_ahead(const FORM *form)
 105 {
 106   bool result = FALSE;
 107
 108   if (form && (form->status & _POSTED) && form->current)
 109     {
 110       static char buffer[SMALL_BUFFER_SIZE + 1];
 111       FIELD *field;
 112       bool large_buffer;
 113       bool cursor_moved = FALSE;
 114       char *bp;
 115       char *found_content;
 116       int pos;
 117
 118       field = form->current;
 119       assert(form->w);
 120
 121       large_buffer = (field->cols > SMALL_BUFFER_SIZE);
 122       if (large_buffer)
 123         bp = (char *)malloc((size_t)(field->cols) + 1);
 124       else
 125         bp = buffer;
 126
 127       assert(bp);
 128
 129       if (Single_Line_Field(field))
 130         {
 131           int check_len;
 132
 133           pos = form->begincol + field->cols;
 134           while (pos < field->dcols)
 135             {
 136               check_len = field->dcols - pos;
 137               if ( check_len >= field->cols )
 138                 check_len = field->cols;
 139               cursor_moved = TRUE;
 140               wmove(form->w,0,pos);
 141               winnstr(form->w,bp,check_len);
 142               found_content =
 143                 After_Last_Non_Pad_Position(bp,check_len,field->pad);
 144               if (found_content==bp)
 145                   pos += field->cols;
 146               else
 147                 {
 148                   result = TRUE;
 149                   break;
 150                 }
 151             }
 152         }
 153       else
 154         {
 155           pos = form->toprow + field->rows;
 156           while (pos < field->drows)
 157             {
 158               cursor_moved = TRUE;
 159               wmove(form->w,pos,0);
 160               pos++;
 161               winnstr(form->w,bp,field->cols);
 162               found_content =
 163                 After_Last_Non_Pad_Position(bp,field->cols,field->pad);
 164               if (found_content!=bp)
 165                 {
 166                   result = TRUE;
 167                   break;
 168                 }
 169             }
 170         }
 171
 172       if (large_buffer)
 173         free(bp);
 174
 175       if (cursor_moved)
 176         wmove(form->w,form->currow,form->curcol);
 177     }
 178   return(result);
 179 }
 180
 181 /* frm_data.c ends here */