% Copyright    Barbara Liskov    1985, 1986

x_cursor = cluster is none, create, cons, scons, destroy, shape,
		      get_id, equal, similar, copy

rep = int

none = proc () returns (cvt)
    return(0)
    end none

create = proc (image, mask: x_bitmap, fore, back, xoff, yoff, func: int)
	   returns (cvt) signals (error(string))
    x_buf$setup(x_storecursor, func, 0, 0)
    x_buf$set_l0s23(b2i(image), fore, back)
    x_buf$set_l2s67(b2i(mask), xoff, yoff)
    x_buf$receive()
       resignal error
    return(x_buf$get_lp0())
    end create

cons = proc (width, height: int, image, mask: _wordvec, fore, back: int,
	     xoff, yoff, func: int) returns (x_cursor) signals (error(string))
    z: int := ((width + 15) / 16) * height * 2
    x_buf$setup(x_storebitmap, 0, 0, 0)
    x_buf$set_s01(height, width)
    x_buf$send_data(w2b(image), 1, z)
    if _wordvec$size(mask) ~= 0
       then x_buf$setup(x_storebitmap, 0, 0, 0)
	    x_buf$set_s01(height, width)
	    x_buf$send_data(w2b(mask), 1, z)
       end
    x_buf$receive()
       except when error (why: string):
		   if _wordvec$size(mask) ~= 0
		      then x_buf$receive()
			      resignal error
		      end
	      end
    img: x_bitmap := _cvt[int, x_bitmap](x_buf$get_lp0())
    msk: x_bitmap := _cvt[int, x_bitmap](0)
    if _wordvec$size(mask) ~= 0
       then x_buf$receive()
	       resignal error
	    msk := _cvt[int, x_bitmap](x_buf$get_lp0())
       end
    cursor: x_cursor := create(img, msk, fore, back, xoff, yoff, func)
       resignal error
    x_bitmap$destroy(img)
    if _wordvec$size(mask) ~= 0
       then x_bitmap$destroy(msk) end
    return(cursor)
    end cons

scons = proc (width, height: int, image, mask: string, fore, back: int,
	      xoff, yoff, func: int) returns (x_cursor) signals (error(string))
    img: _bytevec := _bytevec$create(string$size(image))
    for i: int in int$from_to_by(1, string$size(image), 2) do
	img[i] := image[i + 1]
	img[i + 1] := image[i]
	end
    msk: _bytevec := _bytevec$create(string$size(mask))
    for i: int in int$from_to_by(1, string$size(mask), 2) do
	msk[i] := mask[i + 1]
	msk[i + 1] := mask[i]
	end
    return(cons(width, height, b2w(img), b2w(msk),
		fore, back, xoff, yoff, func))
       resignal error
    end scons

destroy = proc (cursor: cvt)
    x_buf$setup(x_freecursor, 0, 0, 0)
    x_buf$set_l0(cursor)
    end destroy

shape = proc (width, height: int) returns (int, int) signals (error(string))
    x_buf$setup(x_queryshape, CursorShape, 0, 0)
    x_buf$set_s01(height, width)
    x_buf$receive()
       resignal error
    return(x_buf$get_sp1(), x_buf$get_sp2())
    end shape

get_id = proc (cursor: cvt) returns (int)
    return(cursor)
    end get_id

equal = proc (cursor1, cursor2: cvt) returns (bool)
    return(cursor1 = cursor2)
    end equal

similar = proc (cursor1, cursor2: cvt) returns (bool)
    return(cursor1 = cursor2)
    end similar

copy = proc (cursor: cvt) returns (cvt)
    return(cursor)
    end copy

end x_cursor