Re: pl/pgSQL, get diagnostics and big data

Hello,

thanks for reviewing the patch!

On 09.02.2016 20:32, Christian Ullrich wrote:
>
> - Are there portability issues/Will it work on Windows/BSD etc.:
>
>    No, it will not work correctly on Windows when built with MSVC,
>    although it may work with MinGW.
>
>    +++ postgresql-9.5.0/src/backend/tcop/pquery.c
>    @@ -195,7 +195,7 @@
>     {
>       case CMD_SELECT:
>           snprintf(completionTag, COMPLETION_TAG_BUFSIZE,
>    -             "SELECT %u", queryDesc->estate->es_processed);
>    +             "SELECT %lu", queryDesc->estate->es_processed);
>
>
>    %lu formats unsigned long. "long" is problematic in terms of
>    portability, because sizeof(long) is different everywhere. It is 32
>    bits on Windows and on 32-bit *nix, and 64 bits on 64-bit *nix.
>
>    I added the following line to the INSERT formatting in pquery.c:
>
>      queryDesc->estate->es_processed += 471147114711LL;
>
>    This number is 0x6DB28E70D7; so inserting one row should return
>    "INSERT 0 2995679448" (0xB28E70D8):
>
>      postgres=# insert into t1 values (0);
>      INSERT 0 2995679448
>
>    To fix this, I think it will be enough to change the format strings to
>    use "%zu" instead of "%lu". pg_snprintf() is selected by configure if
>    the platform's snprintf() does not support the "z" conversion. I tried
>    this, and it appears to work:
>
>      postgres=# insert into t1 values (0);
>      INSERT 0 471147114712
>
>    I have looked for other uses of "%lu", and found none that may cause
>    the same issue; apparently they are all used with values that clearly
>    have 32-bit type; actually, most of them are used to format error
>    codes in Windows-specific code.

Attached is a new version of the patch, with %lu replaced by %zu.
I re-ran all the tests, especially the long test with 2^32+x rows, and
it produces the same result as before.


Regards,

--
                Andreas 'ads' Scherbaum
German PostgreSQL User Group
European PostgreSQL User Group - Board of Directors
Volunteer Regional Contact, Germany - PostgreSQL Project