Re: [patch]overallocate memory for curly braces in array_out
Keiichi Hirobe <chalenge.akane@gmail.com>
From: Keiichi Hirobe <chalenge.akane@gmail.com>
To: tgl@sss.pgh.pa.us
Cc: PostgreSQL-development <pgsql-hackers@postgresql.org>
Date: 2018-09-26T12:04:51Z
Lists: pgsql-hackers
Attachments
- array_out_bugfix2.patch (application/octet-stream) patch
Hi,
Thanks for the reply.
I am not sure whether to fix another bug, but I fixed and I attached a new
patch,
please check it.
Please note that I inserted a line for updating "overall_length" at line
1185.
I checked below case.
select ARRAY[ARRAY[1,2,3],ARRAY[4,5,6]]; (regular case)
select '[3:4][2:4]={{1,2,3},{4,5,6}}'::_int4; (needdims case)
select ARRAY['a"bc','def']; (needquote case)
Cheers,
Keiichi Hirobe
2018年9月24日(月) 23:46 Tom Lane <tgl@sss.pgh.pa.us>:
> Keiichi Hirobe <chalenge.akane@gmail.com> writes:
> > Attached is a patch that fixes a bug
> > for miscounting total number of curly braces in output string in
> array_out.
>
> Wow, good catch!
>
> Testing this, I found there's a second way in which the space calculation
> is off: it always allocated one more byte than required, as a result of
> counting one more comma than is really required. That's not nearly as
> significant as the curly-brace miscount, but it still got in the way of
> doing this:
>
> *** 1234,1239 ****
> --- 1243,1251 ----
> #undef APPENDSTR
> #undef APPENDCHAR
>
> + /* Assert that we calculated the string length accurately */
> + Assert(overall_length == (p - retval + 1));
> +
> pfree(values);
> pfree(needquotes);
>
>
> which seemed to me like a good idea now that we know this code isn't
> so perfect as all that.
>
> Will push shortly.
>
> regards, tom lane
>
Commits
-
Fix over-allocation of space for array_out()'s result string.
- 87d9bbca13f9 12.0 landed
- bfdd02f88b96 11.0 landed
- ac863108f56b 9.6.11 landed
- 7ecdeb5f5476 9.3.25 landed
- 6ed095edb776 9.5.15 landed
- 103511723ee2 10.6 landed
- 028fc0bac974 9.4.20 landed