bug#62857: CUA rectangle mode in occur edit mode

[Daniel Fleischer <danflscr@gmail.com>]

Eli Zaretskii <eliz@gnu.org> writes:

> Thanks.  This actually reveals a serious bug in the C
> re-implementation of line-number-at-pos: it was signaling an error for
> positions outside of the narrowing, where the original Lisp
> implementation didn't.  I've now fixed this on the emacs-29 branch.
> Can you test the fix?  The diffs are below, for your convenience:

Tested on master 3badd2358d5, works as expected. Thanks!


> diff --git a/src/fns.c b/src/fns.c
> index ff364c6..e8cd621 100644
> --- a/src/fns.c
> +++ b/src/fns.c
> @@ -6116,29 +6116,40 @@ DEFUN ("line-number-at-pos", Fline_number_at_pos,
>  from the absolute start of the buffer, disregarding the narrowing.  */)
>    (register Lisp_Object position, Lisp_Object absolute)
>  {
> -  ptrdiff_t pos, start = BEGV_BYTE;
> +  ptrdiff_t pos_byte, start_byte = BEGV_BYTE;
>  
>    if (MARKERP (position))
> -    pos = marker_position (position);
> +    {
> +      /* We don't trust the byte position if the marker's buffer is
> +         not the current buffer.  */
> +      if (XMARKER (position)->buffer != current_buffer)
> +	pos_byte = CHAR_TO_BYTE (marker_position (position));
> +      else
> +	pos_byte = marker_byte_position (position);
> +    }
>    else if (NILP (position))
> -    pos = PT;
> +    pos_byte = PT_BYTE;
>    else
>      {
>        CHECK_FIXNUM (position);
> -      pos = XFIXNUM (position);
> +      ptrdiff_t pos = XFIXNUM (position);
> +      /* Check that POSITION is valid. */
> +      if (pos < BEG || pos > Z)
> +	args_out_of_range_3 (position, make_int (BEG), make_int (Z));
> +      pos_byte = CHAR_TO_BYTE (pos);
>      }
>  
>    if (!NILP (absolute))
> -    start = BEG_BYTE;
> +    start_byte = BEG_BYTE;
> +  else if (NILP (absolute))
> +    pos_byte = clip_to_bounds (BEGV_BYTE, pos_byte, ZV_BYTE);
>  
> -  /* Check that POSITION is in the accessible range of the buffer, or,
> -     if we're reporting absolute positions, in the buffer. */
> -  if (NILP (absolute) && (pos < BEGV || pos > ZV))
> -    args_out_of_range_3 (make_int (pos), make_int (BEGV), make_int (ZV));
> -  else if (!NILP (absolute) && (pos < 1 || pos > Z))
> -    args_out_of_range_3 (make_int (pos), make_int (1), make_int (Z));
> +  /* Check that POSITION is valid. */
> +  if (pos_byte < BEG_BYTE || pos_byte > Z_BYTE)
> +    args_out_of_range_3 (make_int (BYTE_TO_CHAR (pos_byte)),
> +			 make_int (BEG), make_int (Z));
>  
> -  return make_int (count_lines (start, CHAR_TO_BYTE (pos)) + 1);
> +  return make_int (count_lines (start_byte, pos_byte) + 1);
>  }
>  \f
>  
>
>
>
>

-- 
Daniel Fleischer