Re: Replace some cstring_to_text to cstring_to_text_with_len - Mailing list pgsql-hackers

From John Naylor
Subject Re: Replace some cstring_to_text to cstring_to_text_with_len
Date
Msg-id CAFBsxsGXJSLLXy4TA1bW0TzQENbqdAsU-vNE4TZ_5my+KQnQ3g@mail.gmail.com
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In response to Re: Replace some cstring_to_text to cstring_to_text_with_len  (Ranier Vilela <ranier.vf@gmail.com>)
Responses Re: Replace some cstring_to_text to cstring_to_text_with_len
Re: Replace some cstring_to_text to cstring_to_text_with_len
List pgsql-hackers

On Thu, Aug 31, 2023 at 6:07 PM Ranier Vilela <ranier.vf@gmail.com> wrote:
>
> Em qui., 31 de ago. de 2023 às 00:22, Michael Paquier <michael@paquier.xyz> escreveu:
>>
>> On Wed, Aug 30, 2023 at 03:00:13PM -0300, Ranier Vilela wrote:
>> > cstring_to_text has a small overhead, because call strlen for
>> > pointer to char parameter.
>> >
>> > Is it worth the effort to avoid this, where do we know the size of the
>> > parameter?
>>
>> Are there workloads where this matters?
>
> None, but note this change has the same spirit of 8b26769bc.

- return cstring_to_text("");
+ return cstring_to_text_with_len("", 0);

This looks worse, so we'd better be getting something in return.

@@ -360,7 +360,7 @@ pg_tablespace_location(PG_FUNCTION_ARGS)
  sourcepath)));
  targetpath[rllen] = '\0';
 
- PG_RETURN_TEXT_P(cstring_to_text(targetpath));
+ PG_RETURN_TEXT_P(cstring_to_text_with_len(targetpath, rllen));

This could be a worthwhile cosmetic improvement if the nul-terminator (and space reserved for it, and comment explaining that) is taken out as well, but the patch didn't bother to do that.

--
John Naylor
EDB: http://www.enterprisedb.com

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