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Subject: Re: pg_waldump: support decoding of WAL inside tarfile
From: Chao Li <li.evan.chao@gmail.com>
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Date: Wed, 26 Nov 2025 15:23:39 +0800
Cc: Jakub Wartak <jakub.wartak@enterprisedb.com>,
 Robert Haas <robertmhaas@gmail.com>,
 PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>
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To: Amul Sul <sulamul@gmail.com>
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> On Nov 26, 2025, at 14:02, Amul Sul <sulamul@gmail.com> wrote:
>=20
>> 9 - 0004
>> ```
>> +/*
>> + * Create an astreamer that can read WAL from tar file.
>> + */
>> +static astreamer *
>> +astreamer_waldump_new(XLogDumpPrivate *privateInfo)
>> +{
>> +       astreamer_waldump *streamer;
>> +
>> +       streamer =3D palloc0(sizeof(astreamer_waldump));
>> +       *((const astreamer_ops **) &streamer->base.bbs_ops) =3D
>> +               &astreamer_waldump_ops;
>> +
>> +       streamer->privateInfo =3D privateInfo;
>> +
>> +       return &streamer->base;
>> +}
>> ```
>>=20
>> This function allocates memory for streamer but only returns =
&streamer->base, so memory of streamer is leaked.
>>=20
>=20
> May I know why you think there would be a memory leak? I believe the
> address of the structure is the same as the address of its first
> member, base. I am returning base because the goal is to return a
> generic astreamer type, which is the standard approach used in other
> archive streamer code.

Ah=E2=80=A6 Got it.

Best regards,
--
Chao Li (Evan)
HighGo Software Co., Ltd.
https://www.highgo.com/