Re: control character check in JSON type seems broken

Shigeru Hanada <shigeru(dot)hanada(at)gmail(dot)com> writes:
> json_lex_string() misjudges that the token "" contains naked
> (not-escaped) control character, because its first byte is 0xe3 and it's
> -29 for signed char interpreting, and it's less than 32. We need to
> cast to unsigned char (or use unsigned variable) here.

Yeah, that's wrong.

> In addition, error message above seems corrupted in my environment.
> Here we check not-escaped control character, so printing it with %c
> formatting might break log files. How about using decimal or hex dump
> in such cases?

And so is that. IMO the error reporting in this module could stand to
be reviewed altogether for compliance with our message guidelines.
(For starters, why is it using errdetail_internal?) I refrained from
editorializing on-the-fly, but I'm not too pleased with what I saw.

Patch applied, thanks!

regards, tom lane