utils.c

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 *           scroll horizontally if we're not at beginning of line.
 */
int  move_left( WINDOW *window )
{
int  new_ruler = FALSE;

   if (window->ccol > window->start_col) {
      show_ruler_char( window );
      --window->ccol;
      --window->rcol;
   } else if (window->ccol == window->start_col && window->rcol > 0) {
      --window->rcol;
      --window->bcol;
      window->file_info->dirty = LOCAL;
      new_ruler = TRUE;
   }
   sync( window );
   if (new_ruler) {
      make_ruler( window );
      show_ruler( window );
   }
   return( OK );
}


/*
 * Name:    move_right
 * Purpose: To move the cursor right one character
 * Date:    June 5, 1991
 * Passed:  window:  pointer to current window
 * Notes:   If the cursor is already at the right of the screen (logical
 *          column 80) then scroll horizontally right.
 */
int  move_right( WINDOW *window )
{
int  new_ruler = FALSE;

   if (window->rcol < g_display.line_length - 1) {
      if (window->ccol < window->end_col) {
         show_ruler_char( window );
         ++window->ccol;
         ++window->rcol;
      } else if (window->ccol == window->end_col) {
         ++window->rcol;
         ++window->bcol;
         window->file_info->dirty = LOCAL;
         new_ruler = TRUE;
      }
   }
   sync( window );
   if (new_ruler) {
      make_ruler( window );
      show_ruler( window );
   }
   return( OK );
}


/*
 * Name:    pan_left
 * Purpose: To pan the screen left one character
 * Date:    January 5, 1992
 * Passed:  window:  pointer to current window
 */
int  pan_left( WINDOW *window )
{
/*
 * if (window->bcol == 0) {
 *    if (window->ccol > window->start_col) {
 *       show_ruler_char( window );
 *       --window->ccol;
 *       --window->rcol;
 *    }
 * } else if (window->bcol > 0 ) {
 * * *  Scroll window left function:
 * * *      --window->bcol;
 * * *      if (window->ccol < g_display.ncols - 1)
 * * *         ++window->ccol;
 * * *      else
 * * *         --window->rcol;
 */
   if (window->bcol > 0 ) {
      --window->bcol;
      --window->rcol;
      window->file_info->dirty = LOCAL;
      make_ruler( window );
      show_ruler( window );
   }
   sync( window );
   return( OK );
}


/*
 * Name:    pan_right
 * Purpose: To pan the screen right one character
 * Date:    January 5, 1992
 * Passed:  window:  pointer to current window
 */
int  pan_right( WINDOW *window )
{
   if (window->rcol < g_display.line_length - 1) {
/*
 *      scroll screen right function:
 *      if (window->ccol > 0)
 *         --window->ccol;
 *      else
 *         ++window->rcol;
 */
      ++window->rcol;
      ++window->bcol;
      window->file_info->dirty = LOCAL;
      make_ruler( window );
      show_ruler( window );
   }
   sync( window );
   return( OK );
}


/*
 * Name:    word_left
 * Purpose: To move the cursor left one word
 * Date:    June 5, 1991
 * Passed:  window:  pointer to current window
 * Notes:   Words are considered strings of letters, numbers and underscores,
 *          which must be separated by other characters.
 */
int  word_left( WINDOW *window )
{
text_ptr p;             /* text pointer */
int  len;               /* length of current line */
int  rc;
register int rcol;
long rline;
line_list_ptr ll;
WINDOW w;

   entab_linebuff( );
   if (un_copy_line( window->ll, window, TRUE ) == ERROR)
      return( ERROR );
   rc = OK;
   dup_window_info( &w, window );
   rline = window->rline;
   rcol  = window->rcol;
   ll = window->ll;
   if (ll->len != EOF) {
      p = ll->line;
      len = ll->len;

      if (p != NULL  &&  rcol > 0  &&  rcol >= len  &&
                                      !myiswhitespc( *(p + len - 1) )) {
         rcol = len - 1;
         p += rcol;
         for (; rcol >= 0 && !myiswhitespc( *p ); rcol--, p--);
         ++rcol;
         check_virtual_col( window, rcol, rcol );
         make_ruler( window );
         show_ruler( window );
      } else {
         rcol = rcol >= len ? len-1 : rcol;
         if (rcol >= 0)
            p += rcol;
         if (p != NULL  &&  rcol > 0  &&  !myiswhitespc( *p )  &&
                                          !myiswhitespc( *(p-1) )) {
            for (; rcol >= 0 && !myiswhitespc( *p ); rcol--, p--);
            ++rcol;
            check_virtual_col( window, rcol, rcol );
            make_ruler( window );
            show_ruler( window );
         } else {

            /*
             * if we are on the first letter of a word, get off.
             */
            if (p != NULL)
               for (; rcol >= 0 && !myiswhitespc( *p ); rcol--, p--);

            /*
             * go to the next line if word begins at 1st col in line.
             */
            if (rcol < 0) {
               if (ll->prev != NULL) {
                  --rline;
                  ll = ll->prev;
                  p = ll->line;
                  rcol = ll->len - 1;
                  if (rcol >= 0)
                     p += rcol;
               } else
                  rc = ERROR;
            }

            /*
             * skip all blanks until we get to a previous word
             */
            while (rc == OK  &&  (p == NULL  ||  (p != NULL  &&
                                                  myiswhitespc( *p )))) {
               for (; rcol >= 0 && myiswhitespc( *p ); rcol--, p--);
               if (rcol < 0) {
                  if (ll->prev != NULL) {
                     --rline;
                     ll = ll->prev;
                     p = ll->line;
                     rcol = ll->len - 1;
                     if (rcol >= 0)
                        p += rcol;
                  } else
                     rc = ERROR;
               } else
                  break;
            }

            /*
             * now, find the beginning of the word.
             */
            if (rc == OK  &&  p != NULL) {
               for (; rcol >= 0 && !myiswhitespc( *p ); rcol--, p--);
               bin_offset_adjust( window, rline );
               find_adjust( window, ll, rline, rcol+1 );
               if (rline != w.rline && !window->file_info->dirty) {
                  update_line( &w );
                  show_curl_line( window );
               }
               make_ruler( window );
               show_ruler( window );
            } else
               rc = ERROR;
         }
      }
   } else
      rc = ERROR;

   sync( window );
   return( rc );
}


/*
 * Name:    word_right
 * Purpose: To move the cursor right one word
 * Date:    June 5, 1991
 * Passed:  window:  pointer to current window
 * Notes:   Words are considered strings of letters, numbers and underscores,
 *           which must be separated by other characters.
 */
int  word_right( WINDOW *window )
{
int  len;               /* length of current line */
text_ptr p;             /* text pointer */
int  rc;
WINDOW w;
register int rcol;
line_list_ptr ll;
long rline;

   entab_linebuff( );
   if (un_copy_line( window->ll, window, TRUE ) == ERROR)
      return( ERROR );
   rc = OK;
   dup_window_info( &w, window );
   rline = window->rline;
   rcol  = window->rcol;
   ll = window->ll;
   if (ll->len != EOF) {
      p = ll->line;
      len = ll->len;

      /*
       * if rcol is past EOL, move it to EOL
       */
      rcol = rcol >= len ? len-1 : rcol;
      if (rcol >= 0)
         p += rcol;

      /*
       * if cursor is on a word, find end of word.
       */
      if (p != NULL)
         for (; rcol < len && !myiswhitespc( *p ); rcol++, p++);
      else
         rcol = len;

      /*
       * go to the next line if word ends at eol.
       */
      if (rcol == len) {
         ++rline;
         ll = ll->next;
         if (ll->len != EOF) {
            p = ll->line;
            len = ll->len;
            rcol = 0;
         } else
            rc = ERROR;
      }

      /*
       * now, go forward thru the file looking for the first letter of word.
       */
      while (rc == OK && (p == NULL  ||  (p != NULL && myiswhitespc( *p )))) {
         for (; rcol < len && myiswhitespc( *p ); rcol++, p++);
         if (rcol == len) {
            ++rline;
            ll = ll->next;
            if (ll->len != EOF) {
               p = ll->line;
               len = ll->len;
               rcol = 0;
            } else
               rc = ERROR;
         } else
            break;
      }
   } else
      rc = ERROR;

   if (rc == OK) {
      bin_offset_adjust( window, rline );
      find_adjust( window, ll, rline, rcol );
      make_ruler( window );
      show_ruler( window );
   }

   if (rline != w.rline && !window->file_info->dirty) {
      update_line( &w );
      show_curl_line( window );
   }
   sync( window );
   return( rc );
}


/*
 * Name:    next_dirty_line
 * Purpose: To move the cursor to the next dirty line, if it exists
 * Date:    April 1, 1993
 * Passed:  window:  pointer to current window
 */
int  next_dirty_line( WINDOW *window )
{
int  rc;
line_list_ptr ll;
long rline;
long bin_offset;       /* binary offset */
WINDOW w;

   entab_linebuff( );
   if (un_copy_line( window->ll, window, TRUE ) == ERROR)
      return( ERROR );
   rc = OK;
   dup_window_info( &w, window );
   rline = window->rline;
   ll = window->ll;
   bin_offset = window->bin_offset;
   if (ll->len != EOF) {
      while (rc == OK) {
         if (ll->len != EOF) {
            ++rline;
            bin_offset += ll->len;
            ll = ll->next;
            if (ll->dirty == TRUE)
               break;
         } else
            rc = ERROR;
      }
   } else
      rc = ERROR;

   if (rc == OK) {
      window->bin_offset = bin_offset;
      find_adjust( window, ll, rline, window->rcol );
      make_ruler( window );
      show_ruler( window );
   } else
      error( WARNING, window->bottom_line, utils16 );

   if (rline != w.rline && !window->file_info->dirty) {
      update_line( &w );
      show_curl_line( window );
   }
   sync( window );
   return( rc );
}


/*
 * Name:    prev_dirty_line
 * Purpose: To move the cursor to the prev dirty line, if it exists
 * Date:    April 1, 1993
 * Passed:  window:  pointer to current window
 */
int  prev_dirty_line( WINDOW *window )
{
int  rc;
line_list_ptr ll;
long rline;
long bin_offset;        /* binary offset */
WINDOW w;

   entab_linebuff( );
   if (un_copy_line( window->ll, window, TRUE ) == ERROR)
      return( ERROR );
   rc = OK;
   dup_window_info( &w, window );
   rline = window->rline;
   ll = window->ll;
   bin_offset = window->bin_offset;
   if (ll->prev != NULL) {
      while (rc == OK) {
         if (ll->prev != NULL) {
            --rline;
            ll = ll->prev;
            bin_offset -= ll->len;
            if (ll->dirty == TRUE)
               break;
         } else
            rc = ERROR;
      }
   } else
      rc = ERROR;

   if (rc == OK) {
      window->bin_offset = bin_offset;
      find_adjust( window, ll, rline, window->rcol );
      make_ruler( window );
      show_ruler( window );
   } else
      error( WARNING, window->bottom_line, utils16 );

   if (rline != w.rline && !window->file_info->dirty) {
      update_line( &w );
      show_curl_line( window );
   }
   sync( window );
   return( rc );
}


/*
 * Name:    center_window
 * Purpose: To place the current line or cursor in the center of a window.
 * Date:    June 5, 1991
 * Passed:  window:  pointer to current window
 */
int  center_window( WINDOW *window )
{
int  center;
int  center_line;
int  diff;
register file_infos *file;
register WINDOW *win;           /* put window pointer in a register */

   win = window;
   file = win->file_info;
   center = (win->bottom_line + 1 - win->top_line) / 2 - win->ruler;
   center_line = win->top_line + win->ruler + center;
   diff = center_line - win->cline;
   entab_linebuff( );
   if (un_copy_line( win->ll, win, TRUE ) == ERROR)
      return( ERROR );
   if (g_status.command == CenterWindow) {
      if (diff > 0) {
         if (win->rline + diff <= file->length) {
            upd