Re: A bug when use get_bit() function for a long bytea string

movead(dot)li(at)highgo(dot)ca wrote:

> >I believe the formula for the upper limit in the 32-bit case is:
> > (len <= PG_INT32_MAX / 8) ? (len*8 - 1) : PG_INT32_MAX;
>
> >These functions could benefit from a comment mentioning that
> >they cannot reach the full extent of a bytea, because of the size limit
> >on the bit number.
>
> Because the 2nd argument is describing 'bit' location of every byte in bytea
> string, so an int32 is not enough for that. I think the change is nothing
> wrong,
> or I have not caught your means?

In existing releases, the SQL definitions are set_bit(bytea,int4,int4)
and get_bit(bytea,int4) and cannot be changed to not break the API.
So the patch meant for existing releases has to deal with a too-narrow
int32 bit number.

Internally in the C functions, you may convert that number to int64
if you think it's necessary, but you may not use PG_GETARG_INT64
to pick a 32-bit argument.

Best regards,
--
Daniel Vérité
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