racket/collects/mzlib/os.ss
2005-05-27 18:56:37 +00:00

69 lines
1.8 KiB
Scheme

(module os mzscheme
(require (lib "foreign.ss")) (unsafe!)
(define kernel32
(delay (and (eq? 'windows (system-type))
(ffi-lib "kernel32"))))
(define (delay-ffi-obj name lib type)
(delay (get-ffi-obj name lib type)))
;; ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;; gethostbyname
(define BUFFER-SIZE 1024)
(define (extract-terminated-string proc)
(let ([s (make-bytes BUFFER-SIZE)])
(if (proc s BUFFER-SIZE)
(bytes->string/utf-8 (car (regexp-match #rx#"^[^\0]*" s)))
(error 'gethostname
"could not get hostname"))))
(define unix-gethostname
(delay-ffi-obj "gethostname" #f
(_fun _bytes _int -> _int)))
(define windows-getcomputername
(delay-ffi-obj "GetComputerNameExA" (force kernel32)
(_fun _int _bytes _cvector -> _int)))
(define (gethostname)
(case (system-type)
[(unix macosx)
(let ([ghn (force unix-gethostname)])
(extract-terminated-string
(lambda (s sz)
(zero? (ghn s sz)))))]
[(windows)
(let ([gcn (force windows-getcomputername)]
[DNS_FULLY_QUALIFIED 3])
(extract-terminated-string
(lambda (s sz)
(let ([sz_ptr (cvector _int sz)])
(and (not (zero? (gcn DNS_FULLY_QUALIFIED s sz_ptr)))
(let ([sz (cvector-ref sz_ptr 0)])
(when (sz . < . (bytes-length s))
(bytes-set! s sz 0))
#t))))))]
[else #f]))
(provide gethostname)
;; ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;; getpid
(define unix-getpid
(delay-ffi-obj "getpid" #f
(_fun -> _int)))
(define windows-getpid
(delay-ffi-obj "GetCurrentProcessId" (force kernel32)
(_fun -> _int)))
(define (getpid)
(case (system-type)
[(macosx unix) ((force unix-getpid))]
[(windows) ((force windows-getpid))]))
(provide getpid))