Re: Beautify read stream "per buffer data" APIs

Hi,

I tested both patches on the current master.
The patches applied cleanly, and I reviewed the API changes in
read_stream.h along with the updated call sites, especially in
vacuumlazy. c.
The helper APIs make the code easier to read and reduce the direct
void handling and manual casts in callers.
I also tried reproducing the issue mentioned by Nazir about
read_stream_put_value() not accepting literal constants/rvalues.
Replacing:
read_stream_put_value(stream, per_buffer_data, temp);
with:
read_stream_put_value(stream, per_buffer_data, false);
still results in the following compilation error:
error: lvalue required as unary '&' operand
So the limitation discussed in the thread is still reproducible from my testing.
Other than that, the cleanup and API refactoring look good to me overall.

Regards,
Solai