90 lines
2.5 KiB
Scheme
90 lines
2.5 KiB
Scheme
;;; Copyright (c) 1994 by Olin Shivers
|
|
;;; Add scsh conditions to s48.
|
|
|
|
;;; A syscall-error condition-type:
|
|
|
|
(define-condition-type 'syscall-error '(error))
|
|
|
|
(define syscall-error? (condition-predicate 'syscall-error))
|
|
|
|
(define (errno-error errno msg syscall . stuff)
|
|
(apply signal 'syscall-error errno msg syscall stuff))
|
|
|
|
|
|
(define (with-errno-handler* handler thunk)
|
|
(with-handler
|
|
(lambda (condition more)
|
|
(if (syscall-error? condition)
|
|
(let ((stuff (condition-stuff condition)))
|
|
(handler (car stuff) ; errno
|
|
(cdr stuff)))) ; (msg syscall . packet)
|
|
(more))
|
|
thunk))
|
|
|
|
;;; (with-errno-handler
|
|
;;; ((errno data) ; These are vars bound in this scope.
|
|
;;; ((errno/exist) . body1)
|
|
;;; ((errno/wouldblock errno/again) . body2)
|
|
;;; (else . body3))
|
|
;;;
|
|
;;; . body)
|
|
|
|
(define-syntax with-errno-handler
|
|
(lambda (exp rename compare)
|
|
(let* ((%lambda (rename 'lambda))
|
|
(%cond (rename 'cond))
|
|
(%else (rename 'else))
|
|
(%weh (rename 'with-errno-handler*))
|
|
(%= (rename '=))
|
|
(%begin (rename `begin))
|
|
(%or (rename `or))
|
|
(%call/cc (rename 'call-with-current-continuation))
|
|
(%cwv (rename 'call-with-values))
|
|
|
|
(%ret (rename 'ret)) ; I think this is the way to gensym.
|
|
|
|
(err-var (caaadr exp))
|
|
(data-var (car (cdaadr exp)))
|
|
(clauses (cdadr exp))
|
|
(body (cddr exp))
|
|
|
|
(arms (map (lambda (clause)
|
|
(let ((test (if (compare (car clause) %else)
|
|
%else
|
|
(let ((errs (car clause)))
|
|
`(,%or . ,(map (lambda (err)
|
|
`(,%= ,err ,err-var))
|
|
errs))))))
|
|
`(,test
|
|
(,%cwv (,%lambda () . ,(cdr clause)) ,%ret))))
|
|
clauses)))
|
|
|
|
`(,%call/cc (,%lambda (,%ret)
|
|
(,%weh
|
|
(,%lambda (,err-var ,data-var)
|
|
(,%cond . ,arms))
|
|
(,%lambda () . ,body)))))))
|
|
|
|
;;;; S48 already has this machinery, i.e., (SET-INTERACTIVE?! flag)
|
|
;;;; Interactive => breakpoint on errors.
|
|
;;;; Noninteractive => exit on errors.
|
|
;
|
|
;(define $interactive-errors? (make-fluid #f))
|
|
;
|
|
;(define (with-interactive-errors val thunk)
|
|
; (let-fluid $interactive-errors? val thunk))
|
|
;
|
|
;(define (set-interactive-errors! val)
|
|
; (set-fluid! $interactive-errors? val))
|
|
;
|
|
;;;; Just quit if non-interactive. Otherwise, punt to next handler.
|
|
;;;; A hack, because we use the default handler for the interactive
|
|
;;;; case.
|
|
;
|
|
;(define (scsh-error-handler condition more)
|
|
; (if (and (error? condition)
|
|
; (not (fluid $interactive-errors?)))
|
|
; (begin (display condition (current-error-port))
|
|
; (exit -1))
|
|
; (more)))
|