utils.c

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      win->rline += i;
      win->cline = win->cline + i - win->page;
      win->bin_offset += len;
      win->ll = p;
      win->file_info->dirty = LOCAL;
   } else
      rc = ERROR;
   sync( win );
   return( rc );
}


/*
 * Name:    scroll_down
 * Purpose: scroll window down one line
 * Date:    June 5, 1991
 * Passed:  window:  pointer to current window
 * Notes:   If there is a line to scroll_down, make the window LOCAL dirty.
 *          We have to redraw the screen anyway, so don't update here.
 */
int  scroll_down( WINDOW *window )
{
int  rc = OK;
register WINDOW *win;   /* put window pointer in a register */

   win = window;
   entab_linebuff( );
   if (un_copy_line( win->ll, win, TRUE ) == ERROR)
      return( ERROR );
   if (win->cline == win->top_line + win->ruler) {
      if (win->ll->next != NULL) {
         ++win->rline;
         win->bin_offset += win->ll->len;
         win->ll = win->ll->next;
         win->file_info->dirty = LOCAL;
      } else
         rc = ERROR;
   } else {
      --win->cline;
      win->file_info->dirty = LOCAL;
   }
   sync( win );
   return( rc );
}


/*
 * Name:    scroll_up
 * Purpose: To scroll the window up one line
 * Date:    June 5, 1991
 * Passed:  window:  pointer to current window
 * Notes:   If this is the first page, then update screen here.  Else, make
 *           the window LOCAL dirty because we have to redraw screen.
 */
int  scroll_up( WINDOW *window )
{
int  rc = OK;
register WINDOW *win;   /* put window pointer in a register */

   win = window;
   entab_linebuff( );
   if (un_copy_line( win->ll, win, TRUE ) == ERROR)
      return( ERROR );
   if (win->rline > 1) {
      if (win->rline == (win->cline - (win->top_line + win->ruler - 1))) {
         if (!mode.sync)
            update_line( win );
         win->ll = win->ll->prev;
         win->bin_offset -= win->ll->len;
         --win->rline;
         --win->cline;
         if (!mode.sync)
            show_curl_line( win );
      } else {
         if (win->cline == win->bottom_line) {
            --win->rline;
            win->ll = win->ll->prev;
            win->bin_offset -= win->ll->len;
            win->file_info->dirty = LOCAL;
         } else {
            ++win->cline;
            win->file_info->dirty = LOCAL;
         }
      }
   } else
     rc = ERROR;
   sync( win );
   return( rc );
}


/*
 * Name:    pan_up
 * Purpose: To leave cursor on same logical line and scroll text up
 * Date:    September 1, 1991
 * Passed:  window:  pointer to current window
 * Notes:   If cursor is on first page then do not scroll.
 */
int  pan_up( WINDOW *window )
{
int  rc = OK;
register WINDOW *win;   /* put window pointer in a register */

   win = window;
   entab_linebuff( );
   if (un_copy_line( win->ll, win, TRUE ) == ERROR)
      return( ERROR );

   /*
    * see if cursor is on the first page. if it's not then pan_up.
    */
   if (win->rline != (win->cline+1 - (win->top_line + win->ruler))) {
      if (win->rline > 1) {
         --win->rline;
         win->ll = win->ll->prev;
         win->bin_offset -= win->ll->len;
         win->file_info->dirty = LOCAL;
      }
   } else
      rc = ERROR;
   sync( win );
   return( rc );
}


/*
 * Name:    pan_down
 * Purpose: To leave cursor on same logical line and scroll text down
 * Date:    September 1, 1991
 * Passed:  window:  pointer to current window
 * Notes:   If cursor is on last line in file then do not scroll.
 */
int  pan_down( WINDOW *window )
{
int  rc = OK;
register WINDOW *win;   /* put window pointer in a register */

   win = window;
   entab_linebuff( );
   if (un_copy_line( win->ll, win, TRUE ) == ERROR)
      return( ERROR );
   if (win->ll->len != EOF) {
      ++win->rline;
      win->bin_offset += win->ll->len;
      win->ll = win->ll->next;
      win->file_info->dirty = LOCAL;
   } else
      rc = ERROR;
   sync( win );
   return( rc );
}


/*
 * Name:    show_window_header
 * Purpose: show file stuff in window header
 * Date:    June 5, 1991
 * Passed:  window:  pointer to current window
 * Notes:   Clear line and display header in a lite bar
 */
void show_window_header( WINDOW *window )
{
char status_line[MAX_COLS+2];   /* status line at top of window */
register WINDOW *win;           /* put window pointer in a register */
int  len;

   win = window;
   len = win->vertical ? win->end_col + 1 - win->start_col : win->end_col;

   assert( len >= 0 );
   assert( len <= MAX_COLS );

   memset( status_line, ' ', len );
   status_line[len] = '\0';
   s_output( status_line, win->top_line-1, win->start_col,g_display.head_color);
   show_window_number_letter( win );
   show_window_fname( win );
   show_crlf_mode( win );
   show_size( win );
   show_line_col( win );
}


/*
 * Name:    show_window_number_letter
 * Purpose: show file number and letter of window in lite bar
 * Date:    June 5, 1991
 * Passed:  window:  pointer to current window
 */
void show_window_number_letter( WINDOW *window )
{
int  col;
char temp[10];
register WINDOW *win;   /* put window pointer in a register */

   win = window;
   col = win->start_col;
   s_output( "   ", win->top_line-1, col, g_display.head_color );
   itoa( win->file_info->file_no, temp, 10 );
   s_output( temp, win->top_line-1, strlen( temp ) > 1 ? col : col+1,
             g_display.head_color );
   c_output( win->letter, col+2, win->top_line-1, g_display.head_color );
}


/*
 * Name:    show_window_fname
 * Purpose: show file name in window header.
 * Date:    June 5, 1991
 * Passed:  window:  pointer to current window
 * Notes:   Clear name field and display name in a lite bar
 */
void show_window_fname( WINDOW *window )
{
char status_line[MAX_COLS+2];   /* status line at top of window */
register int  fattr;
char *p;
register WINDOW *win;          /* put window pointer in a register */
int  col;
int  len;

   win = window;
   col = win->start_col;
   len = win->vertical ? 11 : FNAME_LENGTH;

   assert( len >= 0 );
   assert( len <= MAX_COLS );

   memset( status_line, ' ', len );
   status_line[len] = '\0';
   s_output( status_line, win->top_line-1, col+5, g_display.head_color );

   assert( strlen( win->file_info->file_name ) < MAX_COLS );

   strcpy( status_line, win->file_info->file_name );
   p = status_line;
   if (win->vertical) {
      len = strlen( status_line );
      for (p=status_line+len;*(p-1) != ':' && *(p-1) != '\\' && p>status_line;)
         --p;
   } else {
      status_line[FNAME_LENGTH] = '\0';
      p = status_line;
   }
   s_output( p, win->top_line-1, col+5, g_display.head_color );
   if (!win->vertical) {
      fattr = win->file_info->file_attrib;
      p = status_line;
      *p++ = (char)(fattr & ARCHIVE   ? 'A' : '-');
      *p++ = (char)(fattr & SYSTEM    ? 'S' : '-');
      *p++ = (char)(fattr & HIDDEN    ? 'H' : '-');
      *p++ = (char)(fattr & READ_ONLY ? 'R' : '-');
      *p   = '\0';
      s_output( status_line, win->top_line-1, col+51, g_display.head_color );
   }
}


/*
 * Name:    show_crlf_mode
 * Purpose: display state of crlf flag
 * Date:    June 5, 1991
 */
void show_crlf_mode( WINDOW *window )
{
char status_line[MAX_COLS+2];   /* status line at top of window */

   if (!window->vertical) {
      switch (window->file_info->crlf) {
         case LF :
            strcpy( status_line, "lf  " );
            break;
         case CRLF :
            strcpy( status_line, "crlf" );
            break;
         case BINARY :
            strcpy( status_line, "BIN " );
            break;
         default :
            assert( FALSE );
      }
      s_output( status_line, window->top_line-1, window->start_col+56,
                g_display.head_color );
   }
}


/*
 * Name:    show_size
 * Purpose: show number of lines in file
 * Date:    June 5, 1991
 * Passed:  window:  pointer to current window
 */
void show_size( WINDOW *window )
{
char csize[20];

   if (!window->vertical  &&  window->file_info->crlf != BINARY) {
      s_output( "       ", window->top_line-1, 61, g_display.head_color );
      ltoa( window->file_info->length, csize, 10 );
      s_output( csize, window->top_line-1, 61, g_display.head_color );
   }
}


/*
 * Name:    quit
 * Purpose: To close the current window without saving the current file.
 * Date:    June 5, 1991
 * Passed:  window:  pointer to current window
 * Notes:   If the file has been modified but not saved, then the user is
 *           given a second chance before the changes are discarded.
 *          Note that this is only necessary if this is the last window
 *           that refers to the file.  If another window still refers to
 *           the file, then the check can be left until later.
 */
int  quit( WINDOW *window )
{
int  prompt_line;
char line_buff[(MAX_COLS+2)*2]; /* buffer for char and attribute  */
register file_infos *file;
WINDOW *wp;
int  count = 0;
int  rc = OK;

   entab_linebuff( );
   if (un_copy_line( window->ll, window, TRUE ) == ERROR)
      return( ERROR );
   prompt_line = window->bottom_line;
   file = window->file_info;
   for (wp=g_status.window_list; wp != NULL; wp=wp->next) {
      if (wp->file_info == file && wp->visible)
         ++count;
   }
   if (file->modified && count == 1) {
      save_screen_line( 0, prompt_line, line_buff );
      /*
       * abandon changes (y/n)
       */
      set_prompt( utils12, prompt_line );
      if (get_yn( ) != A_YES)
         rc = ERROR;
      restore_screen_line( 0, prompt_line, line_buff );
   }

   /*
    * remove window, allocate screen lines to other windows etc
    */
   if (rc == OK)
      finish( window );
   return( OK );
}


/*
 * Name:    move_up
 * Purpose: To move the cursor up one line
 * Date:    June 5, 1991
 * Passed:  window:  pointer to current window
 * Notes:   If the cursor is at the top of the window, then the file must
 *           be scrolled down.
 */
int  move_up( WINDOW *window )
{
int  rc = OK;
register WINDOW *win;   /* put window pointer in a register */
int  at_top = FALSE;    /* is cline at top of screen? */

   win = window;
   entab_linebuff( );
   if (un_copy_line( win->ll, win, TRUE ) == ERROR)
      return( ERROR );

   /*
    * if no previous line, give up
    */
   if (win->rline > 1) {
      if (win->cline == win->top_line + win->ruler) {
         win->file_info->dirty = LOCAL;
         at_top = TRUE;
      }
      if (!at_top)
         update_line( win );
      --win->rline;             /* ALWAYS decrement line counter */
      win->ll = win->ll->prev;
      win->bin_offset -= win->ll->len;
      if (!at_top) {
         --win->cline;          /* we aren't at top of screen - so move up */
         show_curl_line( win );
      }
   } else
      rc = ERROR;
   sync( win );
   return( rc );
}


/*
 * Name:    move_down
 * Purpose: To move the cursor down one line
 * Date:    June 5, 1991
 * Passed:  window:  pointer to current window
 * Notes:   If the cursor is at the bottom of the window, then the file must
 *           be scrolled up.   If the cursor is at the bottom of the file,
 *           then scroll line up until it is at top of screen.
 */
int  move_down( WINDOW *window )
{
int  rc;

   rc = prepare_move_down( window );
   sync( window );
   return( rc );
}


/*
 * Name:    prepare_move_down
 * Purpose: Do the stuff needed to move the cursor down one line.
 * Date:    June 5, 1991
 * Passed:  window:  pointer to current window
 * Notes:   Put all the stuff needed to move the cursor down one line in
 *           one function, so several functions can use the guts of the
 *           algorithm.
 */
int  prepare_move_down( WINDOW *window )
{
int  rc = OK;
register WINDOW *win;   /* put window pointer in a register */
int  at_bottom = FALSE; /* is cline at bottom of screen */

   win = window;
   entab_linebuff( );
   if (un_copy_line( win->ll, win, TRUE ) == ERROR)
      return( ERROR );
   if (win->cline == win->bottom_line) {
      win->file_info->dirty = LOCAL;
      at_bottom = TRUE;
   }
   if (!at_bottom)
      update_line( win );
   if (win->ll->len != EOF) {
      win->bin_offset += win->ll->len;
      ++win->rline;             /* ALWAYS increment line counter */
      win->ll = win->ll->next;
      if (!at_bottom) {
         ++win->cline;          /* if not at bottom of screen move down */
         show_curl_line( win );
      }
   } else if (win->cline > win->top_line + win->ruler) {
      --win->cline;
      win->file_info->dirty = LOCAL;
      rc = ERROR;
   } else
      rc = ERROR;
   return( rc );
}


/*
 * Name:    move_left
 * Purpose: To move the cursor left one character
 * Date:    June 5, 1991
 * Passed:  window:  pointer to current window
 * Notes:   If the cursor is already at the left of the screen, then