Re: encode/decode support for base64url

On Sep 19, 2025, at 14:45, Florents Tselai <florents.tselai@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)”.

IIUC what you mean, I can’t confirm that.

Both existing and new implementation handle new lines the same 

SELECT decode(E'QUFB\nQUFB', 'base64url');

     decode     

----------------

 \x414141414141

(1 row)

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 

Well, that’s a very interesting catch. 

I’ll let a comitter confirm & advise.