Module m4a_attach 

POST /m4a/attach: on-demand m4a account for a provider session the node did not spawn (spec live-session-m4a-attach).

Caller: m4a-agent mcp running inside that provider session. Checks, all required:

1. owner: the ops listener’s owner-only control token (a file only the node’s OS user can read) – checked by the router before this module runs;
2. policy: HATCHERY_M4A_ATTACH (default auto; set off to refuse) and the provider in HATCHERY_M4A_ATTACH_PROVIDERS (default: all built-in providers);
3. process: the given pid is alive and descends (within a few generations) from a live process of that provider. Then the node provisions a per-session account (own registry entry, own store root and key) keyed by the provider session id (or the provider’s pid when none is known) and returns nick, session id and a fresh capability. The capability is returned once, never logged.

Structs

Proc

Constants

POLICY_ENV

PROVIDERS_ENV

Functions

attach_policy_is_auto

Adoption policy: unset or auto → allow; off/0/false → refuse.

handle

Handles the request; table is the current process table (injected for tests).

pick_adopted

The adopted session an attach belongs to: the session it names, else the one on the provider’s command line when that one is adopted, else the only adopted session. Several adopted sessions and nothing to tell them apart is an error, never a new account.

policy_allows

process_table

The live process table.

provider_ancestor

Walks from pid up the parent chain; returns the nearest process whose image is the provider.

provider_images

Process image base names that count as provider.

query_get

valid_session