Rename VSB_QUOTE_JSON and prepare VSB_quote_*() for returning errors

[nigoroll]

We rename our existing JSON quoting to make clear that it is not quite JSON.

For standard JSON quoting, we are going to need to signal failures, so prepare VSB_quote*() for that.

[dridi]

I find this too intrusive.

In general adding a return value to VSB_quote*() is a good idea, but instead of guarding against failure everywhere, we should relax the return value check for flexelint. This is what we do in many places: feed the VSB and wait until VSB_finish() to check for errors. Consumers of VSB_quote*() may otherwise perform early checks when relevant.

Even worse, the indiscriminate coccinelle patch added assertion to panic code paths, potentially raising a signal inside a signal handler.

I think we should limit the change to vsb.c, vsb.h and /flint.lnt.

I haven't thought about the JSON part of the change.

[dridi]

Also, this is an ABI breaking change that would probably require a major soname bump of libvarnishapi.

[nigoroll]

Discussed on IRC: @bsdphk does not see standard conforming JSON encoding as a core function of VSB, so together with @dridi's objections, the API change is dead.
I wonder if we should still do the JSON->VJSON rename to make it obvious that it's not-quite-json.

[nigoroll]

I wonder if we should still do the JSON->VJSON rename to make it obvious that it's not-quite-json.

dismissed on irc