WASIX + WAI: Thread Spawning and Process Forking

[theduke]

For WAI generated bindings to work correctly with WASIX, they need to support both thread spawning and process forking.

In particular this means:

• threads: the context generated by WAI must be thread-safe, and must be cloneable and shareable, so we can use the same context for different thread instances. There also must be a way to initialize bindings for a new instance with the existing context (including the FD tables!)
• forking: the context must expose a way to mirror / duplicate an existing context (including things like FD handles) , which can then be used for forked processes

Note: currently custom bindings are only used for wasix_http_client, so the impact is limited at the moment, but using the client together with WASIX threads or processes is currently broken, unless each process/thread constructs a new client instead of sharing / sending a specific client across threads or using an existing client in a newly forked process.

@Michael-F-Bryan

[stale[bot]]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[stale[bot]]

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