Re: quoting psql varible as identifier

On Sun, Jan 17, 2010 at 2:04 PM, Pavel Stehule <pavel.stehule@gmail.com> wrote:
> I rewrote patch so now interface for PQescapeIdentConn is same as
> PQescapeStringConn
>
> @3. I though so the protection under incomplete multibyte chars are
> enought - missing bytes are replaced by space - like
> PQescapeStringConn does.

That much is fine, but the output buffer is only guaranteed to be of
size 2n+1.  Imagine the input is two double-quotes followed by a byte
for which pg_encoding_mblen() returns 4.  The input is 3 characters
long so the user was responsible to provide 7 bytes of output space,
but you'll try to write 9 bytes to it (including the terminating NUL).

> But now - mechanism is exactly same, so this
> problem should be solved.

This is no better.  What the function does no longer matches either
its comments or the documentation (which also contradict each other).

Let me take a crack at this and post a patch.  We're making this
harder than it needs to be.

...Robert