* libtiff/tif_read.c, libtiff/tiffiop.h: fix uint32 overflow in
TIFFReadEncodedStrip() that caused an integer division by zero.
Reported by Agostino Sarubbo.
Fixes http://bugzilla.maptools.org/show_bug.cgi?id=2596
TIFFReadTile(TIFF* tif, void* buf, uint32 x, uint32 y, uint32 z, uint16 s)
{
	if (!TIFFCheckRead(tif, 1) || !TIFFCheckTile(tif, x, y, z, s))
		return ((tmsize_t)(-1));
	return (TIFFReadEncodedTile(tif,
	    TIFFComputeTile(tif, x, y, z, s), buf, (tmsize_t)(-1)));
}

TIFFReadTile(TIFF* tif, void* buf, uint32 x, uint32 y, uint32 z, uint16 s)
{
	if (!TIFFCheckRead(tif, 1) || !TIFFCheckTile(tif, x, y, z, s))
		return ((tmsize_t)(-1));
	return (TIFFReadEncodedTile(tif,
	    TIFFComputeTile(tif, x, y, z, s), buf, (tmsize_t)(-1)));
}
