Re: making the backend's json parser work in frontend code

On Sun, Jan 26, 2020 at 9:05 PM Mark Dilger
<mark(dot)dilger(at)enterprisedb(dot)com> wrote:
> Ok, the tests pass. Here are those two patches again, both regenerated with a fresh invocation of ‘git format-patch’.

Regarding 0006:

+#ifndef FRONTEND
#include "miscadmin.h"
-#include "utils/jsonapi.h"
+#endif

I suggest

#ifdef FRONTEND
#define check_stack_depth()
#else
#include "miscadmin.h"
#endif

- lex->token_terminator = s + pg_mblen(s);
+ lex->token_terminator = s +
pg_wchar_table[lex->input_encoding].mblen((const unsigned char *) s);

Can we use pq_encoding_mblen() here? Regardless, it doesn't seem great
to add more direct references to pg_wchar_table. I think we should
avoid that.

+ return JSON_BAD_PARSER_STATE;

I don't like this, either. I'm thinking about adding some
variable-argument macros that either elog() in backend code or else
pg_log_fatal() and exit(1) in frontend code. There are some existing
precedents already (e.g. rmtree.c, pgfnames.c) which could perhaps be
generalized. I think I'll start a new thread about that.

--
Robert Haas
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