module/slib/getopt.scm

   1 ;;; "getopt.scm" POSIX command argument processing
   2 ;Copyright (C) 1993, 1994 Aubrey Jaffer
   3 ;
   4 ;Permission to copy this software, to redistribute it, and to use it
   5 ;for any purpose is granted, subject to the following restrictions and
   6 ;understandings.
   7 ;
   8 ;1.  Any copy made of this software must include this copyright notice
   9 ;in full.
  10 ;
  11 ;2.  I have made no warrantee or representation that the operation of
  12 ;this software will be error-free, and I am under no obligation to
  13 ;provide any services, by way of maintenance, update, or otherwise.
  14 ;
  15 ;3.  In conjunction with products arising from the use of this
  16 ;material, there shall be no use of my name in any advertising,
  17 ;promotional, or sales literature without prior written consent in
  18 ;each case.
  19
  20 (define getopt:scan #f)
  21 (define getopt:char #\-)
  22 (define getopt:opt #f)
  23 (define *optind* 1)
  24 (define *optarg* 0)
  25
  26 (define (getopt argc argv optstring)
  27   (let ((opts (string->list optstring))
  28         (place #f)
  29         (arg #f)
  30         (argref (lambda () ((if (vector? argv) vector-ref list-ref)
  31                             argv *optind*))))
  32     (and
  33      (cond ((and getopt:scan (not (string=? "" getopt:scan))) #t)
  34            ((>= *optind* argc) #f)
  35            (else
  36             (set! arg (argref))
  37             (cond ((or (<= (string-length arg) 1)
  38                        (not (char=? (string-ref arg 0) getopt:char)))
  39                    #f)
  40                   ((and (= (string-length arg) 2)
  41                         (char=? (string-ref arg 1) getopt:char))
  42                    (set! *optind* (+ *optind* 1))
  43                    #f)
  44                   (else
  45                    (set! getopt:scan
  46                          (substring arg 1 (string-length arg)))
  47                    #t))))
  48      (begin
  49        (set! getopt:opt (string-ref getopt:scan 0))
  50        (set! getopt:scan
  51              (substring getopt:scan 1 (string-length getopt:scan)))
  52        (if (string=? "" getopt:scan) (set! *optind* (+ *optind* 1)))
  53        (set! place (member getopt:opt opts))
  54        (cond ((not place) #\?)
  55              ((or (null? (cdr place)) (not (char=? #\: (cadr place))))
  56               getopt:opt)
  57              ((not (string=? "" getopt:scan))
  58               (set! *optarg* getopt:scan)
  59               (set! *optind* (+ *optind* 1))
  60               (set! getopt:scan #f)
  61               getopt:opt)
  62              ((< *optind* argc)
  63               (set! *optarg* (argref))
  64               (set! *optind* (+ *optind* 1))
  65               getopt:opt)
  66              ((and (not (null? opts)) (char=? #\: (car opts))) #\:)
  67              (else #\?))))))
  68
  69 (define (getopt-- argc argv optstring)
  70   (let* ((opt (getopt argc argv (string-append optstring "-:")))
  71          (optarg *optarg*))
  72     (cond ((eqv? #\- opt)               ;long option
  73            (do ((l (string-length *optarg*))
  74                 (i 0 (+ 1 i)))
  75                ((or (>= i l) (char=? #\= (string-ref optarg i)))
  76                 (cond
  77                  ((>= i l) (set! *optarg* #f) optarg)
  78                  (else (set! *optarg* (substring optarg (+ 1 i) l))
  79                        (substring optarg 0 i))))))
  80           (else opt))))