Subject: Re: automatically generating node support functions
To: Peter Eisentraut <peter.eisentraut@enterprisedb.com>,
 pgsql-hackers <pgsql-hackers@postgresql.org>
References: <c1097590-a6a4-486a-64b1-e1f9cc0533ce@enterprisedb.com>
 <2f876203-7142-fa71-6d22-6ce00eb26869@enterprisedb.com>
 <c091e5cd-45f8-69ee-6a9b-de86912cc7e7@enterprisedb.com>
 <b85eec6e-a54b-6c72-97f8-2a6fbf4f9070@enterprisedb.com>
 <c683a356-4d22-4126-bf55-64ed54e06014@enterprisedb.com>
From: Andrew Dunstan <andrew@dunslane.net>
Message-ID: <50fedc80-4104-bdc8-d777-04f030fc550f@dunslane.net>
Date: Tue, 12 Oct 2021 09:52:15 -0400
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On 10/11/21 10:22 AM, Peter Eisentraut wrote:
>
> On 15.09.21 21:01, Peter Eisentraut wrote:
>> On 17.08.21 16:36, Peter Eisentraut wrote:
>>> Here is another set of preparatory patches that clean up various
>>> special cases and similar in the node support.
>>
>> This set of patches has been committed.  I'll close this commit fest
>> entry and come back with the main patch series in the future.
>
> Here is an updated version of my original patch, so we have something
> to continue the discussion around.  This takes into account all the
> preparatory patches that have been committed in the meantime.  I have
> also changed it so that the array size of a pointer is now explicitly
> declared using pg_node_attr(array_size(N)) instead of picking the most
> recent scalar field, which was admittedly hacky.  I have also added
> MSVC build support and made the Perl code more portable, so that the
> cfbot doesn't have to be sad.


I haven't been through the whole thing, but I did notice this: the
comment stripping code looks rather fragile. I think it would blow up if
there were a continuation line not starting with  qr/\s*\*/. It's a lot
simpler and more robust to do this if you slurp the file in whole.
Here's what we do in the buildfarm code:

    my $src = file_contents($_);
    # strip C comments
    # We used to use the recipe in perlfaq6 but there is actually no point.
    # We don't need to keep the quoted string values anyway, and
    # on some platforms the complex regex causes perl to barf and crash.
    $src =~ s{/\*.*?\*/}{}gs;

After you've done that splitting it into lines is pretty simple.

cheers


andrew

--
Andrew Dunstan
EDB: https://www.enterprisedb.com