Joseph Ferano
e9c0e96a9b
The path was ceremony. Under [flan dev] the daemon already decides where it wants to talk to the program and writes it into FLAN_AGENT_SOCKET, which the C side has always honoured over whatever the source named — so the argument was a value nothing read. Outside the daemon any path will do as long as the program says which one it picked. So [start] becomes a macro over two functions: no argument picks the daemon's socket if there is one and otherwise /tmp/flan-agent-<pid>-<clock>.sock, announced on stderr because a socket nobody can name is a socket nobody can connect to. The explicit form stays for a program that wants a fixed path. Extra arguments are spliced into [start-at] rather than dropped, so the arity refusal is still the checker's, at the call site. And the socket is removed on the way out. The bind stashes the path it bound and registers an atexit; the two paths that leave by _exit — the break loop's [abort] and the orphan handler — unlink it by hand, as the orphan handler already did for its own copy of the path. Nothing else takes it away: under the daemon it sits in a temp directory that is still never removed (FIX.org), and outside there is no daemon at all. test/programs/dev-loop.flan now names no socket, which puts the whole daemon block in test_dev.ml behind the zero-argument form; agent-auto.flan is the standalone half, reached only through the line the program printed, and it pins the second (agent/start) as a no-op and the socket as gone at exit.
48 lines
2.5 KiB
Plaintext
48 lines
2.5 KiB
Plaintext
;;;; The dev agent, as Flan sees it. Three calls, and the shape of them is the
|
|
;;;; design: loading a redefinition and installing it are separate, because
|
|
;;;; only the program knows when it is between frames.
|
|
;;;;
|
|
;;;; (agent/start) listen somewhere sensible; once, at startup
|
|
;;;; (agent/start path) listen on that unix socket instead
|
|
;;;; (agent/poll) install whatever has arrived; returns how many
|
|
;;;; (agent/wait ms) the same, but waits for something first
|
|
;;;;
|
|
;;;; A game loop calls poll at the top of the frame and ignores the result.
|
|
;;;; wait is for a headless test, where waiting is what makes a reload
|
|
;;;; deterministic rather than a race against the frame rate.
|
|
;;;;
|
|
;;;; The path was the ceremony. Under [flan dev] the daemon has already decided
|
|
;;;; where it wants to talk to the program and says so in FLAN_AGENT_SOCKET, so
|
|
;;;; whatever the source named was being overridden anyway; outside the daemon
|
|
;;;; any path will do as long as the program says which one it picked. So the
|
|
;;;; argument is now optional, and the zero-argument form is the one to write.
|
|
;;;; The explicit form stays for a program that wants to choose — a fixed path
|
|
;;;; something else is already configured to connect to.
|
|
;;;;
|
|
;;;; No aggregate crosses this boundary, so there is no shim: a Flan string is
|
|
;;;; already ptr+len and flan_agent_start takes it that way.
|
|
(declare start-at-raw [path string] i32 "flan_agent_start")
|
|
(declare start-auto-raw [] i32 "flan_agent_start_auto")
|
|
(declare poll-raw [] i32 "flan_agent_poll")
|
|
(declare wait-raw [ms i32] i32 "flan_agent_wait")
|
|
|
|
;;; Both answer 0 for "listening" and -1 for "could not". Starting twice is not
|
|
;;; an error and not a second listener: the C side answers 0 and leaves the
|
|
;;; first socket alone, so a program that gets a listener from somewhere else
|
|
;;; and also calls start is a program with one listener.
|
|
(defn start-at [path string] i32 (start-at-raw path))
|
|
(defn start-auto [] i32 (start-auto-raw))
|
|
|
|
;;; The optional argument, which Flan has no other spelling for: a function
|
|
;;; takes the arity it declares, so the choice between the two above is made
|
|
;;; before the checker ever sees a call. Extra arguments are not silently
|
|
;;; dropped — they are spliced into [start-at], which then refuses them by its
|
|
;;; own arity, at the call site, in the usual words.
|
|
(defmacro start [& args]
|
|
(if (= (len args) 0)
|
|
`(start-auto)
|
|
`(start-at ~@args)))
|
|
|
|
(defn poll [] i32 (poll-raw))
|
|
(defn wait [ms i32] i32 (wait-raw ms))
|