Replace YAJL with yyjson for JSON parsing and generation

[giuseppe]

No description provided.

[xw19]

@giuseppe will we keep yyjson statically linked?

[giuseppe]

we need to support both ways, statically and dynamically linked

[giuseppe]

@jnovy what do you think of this change?

[giuseppe]

@jnovy @kolyshkin are you OK to move forward with this?

It is a quite significant change, that needs to happen in crun too, but we will finally get rid of the unmaintained libyajl dependency

[jnovy]

@giuseppe it's a similar trap like yajl we are about to introduce merging this. yyjson doesn't exist in RHEL so we need claim its maintenance and go through the painful new package process. Alternatively to stick it in the code directly and maintain it. What is wrong with just json-c which is available everywhere?

[giuseppe]

When I compared them, json-c does not have support for uint64 (https://github.com/json-c/json-c/blob/master/json_types.h#L62-L73), anything above INT64_MAX will overflow. This is a blocker for us.

[jnovy]

I see - LGTM then if we vendor this in on RHEL and use OS variant in Fedora and other distros containing yyjson.

[giuseppe]

thanks for the review!

I'll merge once we are also fine with containers/crun#2068

[jnovy]

@giuseppe just digged into json-c more and it actually does have uint64 support since version 0.14 (2020). The json_type enum you linked doesn't show it because json-c uses json_type_int as the public type with an internal subtype discriminator. The public API includes json_object_new_uint64(), json_object_get_uint64(), etc. RHEL 9 ships json-c 0.14 and RHEL 10 ships 0.18, both with full uint64 support.

[giuseppe]

thanks, I'll play with it and we can compare once I get something working