scsh-0.6/scsh/startup.scm

106 lines
3.5 KiB
Scheme

;;; Scsh start-up code.
;;; Copyright (c) 1995 by Olin Shivers.
;;; A scsh starter takes the command line args, parses them,
;;; initialises the scsh system, and either starts up a repl loop
;;; or executes the -s script.
(define (make-scsh-starter)
(let ((context (user-context)))
(lambda (args)
(parse-switches-and-execute args context))))
;;; Had to define these as the ones in s48's build.scm do not properly
;;; initialise ERROR-OUTPUT-PORT to stderr -- this is a bug in the vm's
;;; handoff to the very first Scheme form (it passes two ports -- not three).
;;; Until Kelsey fixes these, we hack it with these replacements, which
;;; invoke INIT-SCSH-HINDBRAIN, which re-initialises the I/O system to be
;;; what you wanted.
;;; WRITE-IMAGE calls the starter after installing a fatal top-level
;;; error handler. MAKE-SCSH-STARTER shadows it in the interactive case.
(define (really-dump-scsh-program start filename)
(let ((filename (translate filename)))
(display (string-append "Writing " filename) (command-output))
(newline (command-output))
;JMG: it is set to #f in the vm, so I omit it now
;;;(flush-the-symbol-table!) ;Gets restored at next use of string->symbol
(write-image filename
(scsh-stand-alone-resumer start)
"Scsh 0.6")
#t))
;;; This one relies on the scsh top-level command-line switch parser
;;; to decide whether to do the scsh-var inits quietly or with warnings.
(define (dump-scsh fname)
(really-dump-scsh-program (make-scsh-starter) fname))
;;; Init the scsh run-time's vars quietly before running the program.
;;; This is what we export to the user for his programs.
(define (dump-scsh-program start filename)
(let ((context (user-context)))
(really-dump-scsh-program (lambda (args)
(with-scsh-sighandlers
#f
(lambda ()
(with-autoreaping
(lambda ()
(install-env)
(initialize-cwd)
(init-scsh-vars #f) ; Do it quietly.
(start-new-session context
(current-input-port)
(current-output-port)
(current-error-port)
args
#f)
(with-interaction-environment
(user-environment)
(lambda ()
(start args))))))))
filename)))
(define (scsh-stand-alone-resumer start)
(usual-resumer ; sets up exceptions, interrupts,
; and current input & output
(lambda (args) ; VM gives us our args, but not our program.
(init-fdports!)
(call-with-current-continuation
(lambda (halt)
(set! %vm-prog-args (cons "scsh" args)) ; WRONG -- use image.
(set-command-line-args! %vm-prog-args)
(with-handler
(simple-condition-handler halt (current-error-port))
(lambda ()
(let ((dynamic-env (get-dynamic-env))
(*result* 4711))
(let ((runnable (make-thread-queue))
(thread (make-thread (lambda ()
(set! *result*
(start (command-line))))
dynamic-env
'scsh-initial-thread))
(thread-count (make-counter)))
(enqueue-thread! runnable thread)
(increment-counter! thread-count)
(run-threads
(round-robin-event-handler runnable 200 dynamic-env thread-count
(lambda args #f)
(lambda (thread token args) ; upcall handler
(propogate-upcall thread token args))
(lambda ()
(if (positive? (counter-value thread-count))
((structure-ref threads-internal wait))
#f))))
(if (integer? *result*) *result* 0)))))))))) ; work around bug.
(define %vm-prog-args #f)