racket/collects/mzlib/compile.rkt
2011-09-27 19:28:44 -06:00

65 lines
2.7 KiB
Racket

#lang racket/base
(require racket/function
racket/path
racket/file
unstable/file)
(provide compile-file)
(define compile-file
(case-lambda
[(src)
(define cdir (build-path (path-only src) "compiled"))
(make-directory*/ignore-exists-exn cdir)
(compile-file src (build-path cdir (path-add-suffix (file-name-from-path src) #".zo")))]
[(src dest)
(compile-file src dest values)]
[(src dest filter)
(define in (open-input-file src))
(dynamic-wind
void
(lambda ()
(define ok? #f)
; This must be based on the path to dest. Renaming typically cannot be done
; atomically across file systems, so the temporary directory is not an option
; because it is often a ram disk. src (or dir below) couldn't be used because
; it may be on a different filesystem. Since dest must be a file path, this
; guarantees that the temp file is in the same directory. It would take a weird
; filesystem configuration to break that.
(define temp-filename (make-temporary-file "tmp~a" #f (path-only dest)))
(port-count-lines! in)
(dynamic-wind
void
(lambda ()
; XXX: This seems like it should be a library function named 'relative-path-only'
(define dir
(let-values ([(base name dir?) (split-path src)])
(if (eq? base 'relative)
(current-directory)
(path->complete-path base (current-directory)))))
(define out (open-output-file temp-filename #:exists 'truncate/replace))
(parameterize ([current-load-relative-directory dir]
[current-write-relative-directory dir])
; Rather than installing a continuation barrier, we detect reinvocation.
; The only thing that can cause reinvocation is if the filter captures the
; continuation and communicates it externally.
(define count 0)
(dynamic-wind
(lambda ()
(if (zero? count)
(set! count 1)
(error 'compile-file "filter function should not be re-entrant")))
(lambda ()
(for ([r (in-port (curry read-syntax src) in)])
(write (compile-syntax (filter (namespace-syntax-introduce r))) out))
(set! ok? #t))
(lambda ()
(close-output-port out)))))
(lambda ()
(if ok?
(rename-file-or-directory temp-filename dest #t)
(with-handlers ([exn:fail:filesystem? void])
(delete-file temp-filename))))))
(lambda () (close-input-port in)))
dest]))