Re: encode/decode support for base64url

On 19 Sep 2025, at 6:50 AM, Chao Li <li.evan.chao@gmail.com> wrote:

I reviewed and tested this patch. Overall looks good to me. Actually, I think this patched fixed a bug of current implementation of base64 encoding by moving the logic of handling newline into “if (pos<0)”.

Just a few small comments:

On Sep 19, 2025, at 03:19, Daniel Gustafsson <daniel@yesql.se> wrote:

<v9-0001-Add-support-for-base64url-encoding-and-decoding.patch>

1.

```

+ * Helper for decoding base64 or base64url.  When url is passed as true the

+ * input will be encoded using base64url.  len bytes in src is encoded into

+ * dst.

+ */

```

It’s not common to use two white-spaces after “.”, usually we need only one.

2.

```

+ /* handle remainder */

  if (pos != 2)

```

The comment is understandable, but slightly vague: remainder of what?

Maybe rephrase to “handle remaining bytes in buf”.

3.

```

  ereport(ERROR,

  (errcode(ERRCODE_INVALID_PARAMETER_VALUE),

- errmsg("unexpected \"=\" while decoding base64 sequence")));

+ errmsg("unexpected \"=\" while decoding %s sequence", url ? "base64url" : "base64")));

```

This is a normal usage that injects sub-strings based on condition. However, PG doesn’t like that, see here: https://www.postgresql.org/docs/devel/nls-programmer.html#NLS-GUIDELINES