Re: logical replication launcher crash on buildfarm

On 28/03/17 17:55, Robert Haas wrote:
> On Mon, Mar 27, 2017 at 11:20 PM, Petr Jelinek
> <petr(dot)jelinek(at)2ndquadrant(dot)com> wrote:
>> On 28/03/17 04:46, Robert Haas wrote:
>>> On Mon, Mar 27, 2017 at 10:04 PM, Andres Freund <andres(at)anarazel(dot)de> wrote:
>>>>> Btw now that I look at the code, I guess we'll want to get rid of
>>>>> bgw_main completely in HEAD given that we can't guarantee it will be
>>>>> valid even for shared_preload_library libraries. For older branches I
>>>>> would leave things as they are in this regard as there don't seem to be
>>>>> any immediate issue for standard binaries.
>>>>
>>>> As long as you fix it so culicidae is happy (in 9.6) ;). I think it's
>>>> fine to just introduce bgw_builtin_id or such, and leave the bgw_main
>>>> code in place in < HEAD.
>>>
>>> I wasn't thinking of introducing bgw_builtin_id. My idea was just
>>> along the lines of
>>>
>>> if (bgw_library_name == NULL && bgw_function_name != NULL)
>>> {
>>> if (strcmp(bgw_function_name, "ParallelQueryMain") == 0)
>>> ParallelQueryMain(blah);
>>> else if (strcmp(bgw_function_name, "LogicalReplicationMain") == 0)
>>> LogicalReplicationMain(blah);
>>> }
>>>
>>> I think something like that is certainly better for the back-branches,
>>> because it doesn't cause an ABI break. But I think it would also be
>>> fine for master.
>>>
>>
>> I had something slightly more complex like the attached in mind.
>
> Seems broadly reasonable on a quick look, but I think we should leave
> bgw_main intact in 9.6. It may be working for fine for people who
> don't care about Windows, and I'd rather not break it gratuitously.
> Can we have two patches, one of which converts the internal stuff to
> use the new mechanism and a second of which removes bgw_main? The
> second one, at least, also needs to update the documentation. (A good
> practice when removing an identifier is to run 'git grep
> thing_i_am_removing' after removing it...)
>

Yes I agree (and I said it in the thread) I plan to submit the 9.6 too,
I just sent what I had before having it all ready mainly because you
started talking about code already and I didn't want you to waste time
with it needlessly, but it was already 5AM for me ;).

--
Petr Jelinek http://www.2ndQuadrant.com/
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