/usr/share/slib/scanf.scm is in slib 3b1-3.1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 | ;;;;"scanf.scm" implemenation of formatted input
;Copyright (C) 1996, 1997, 2003 Aubrey Jaffer
;
;Permission to copy this software, to modify it, to redistribute it,
;to distribute modified versions, and to use it for any purpose is
;granted, subject to the following restrictions and understandings.
;
;1. Any copy made of this software must include this copyright notice
;in full.
;
;2. I have made no warranty or representation that the operation of
;this software will be error-free, and I am under no obligation to
;provide any services, by way of maintenance, update, or otherwise.
;
;3. In conjunction with products arising from the use of this
;material, there shall be no use of my name in any advertising,
;promotional, or sales literature without prior written consent in
;each case.
;;; Originally jjb@isye.gatech.edu (John Bartholdi) wrote some public
;;; domain code for a subset of scanf, but it was too difficult to
;;; extend to POSIX pattern compliance. Jan 96, I rewrote the scanf
;;; functions starting from the POSIX man pages.
(require 'string-port)
(require 'rev2-procedures)
(require 'rev4-optional-procedures)
(define (stdio:scan-and-set format-string input-port . args)
(define setters (if (equal? '(#f) args) #f args))
(define assigned-count 0)
(define chars-scanned 0)
(define items '())
(define (return)
(cond ((and (zero? chars-scanned)
(eof-object? (peek-char input-port)))
(peek-char input-port))
(setters assigned-count)
(else (reverse items))))
(cond
((equal? "" format-string) (return))
((string? input-port)
(call-with-input-string
input-port
(lambda (str-port)
(apply stdio:scan-and-set format-string str-port args))))
(else
(call-with-input-string
format-string
(lambda (format-port)
(define (char-non-numeric? c) (not (char-numeric? c)))
(define (flush-whitespace port)
(do ((c (peek-char port) (peek-char port))
(i 0 (+ 1 i)))
((or (eof-object? c) (not (char-whitespace? c))) i)
(read-char port)))
(define (flush-whitespace-input)
(set! chars-scanned (+ (flush-whitespace input-port) chars-scanned)))
(define (read-input-char)
(set! chars-scanned (+ 1 chars-scanned))
(read-char input-port))
(define (add-item report-field? next-item)
(cond (setters
(cond ((and report-field? (null? setters))
(slib:error 'scanf "not enough variables for format"
format-string))
((not next-item) (return))
((not report-field?) (loop1))
(else
(let ((suc ((car setters) next-item)))
(cond ((not (boolean? suc))
(slib:warn 'scanf "setter returned non-boolean"
suc)))
(set! setters (cdr setters))
(cond ((not suc) (return))
((eqv? -1 report-field?) (loop1))
(else
(set! assigned-count (+ 1 assigned-count))
(loop1)))))))
((not next-item) (return))
(report-field? (set! items (cons next-item items))
(loop1))
(else (loop1))))
(define (read-string width separator?)
(cond (width
(let ((str (make-string width)))
(do ((i 0 (+ 1 i)))
((>= i width)
str)
(let ((c (peek-char input-port)))
(cond ((eof-object? c)
(set! str (substring str 0 i))
(set! i width))
((separator? c)
(set! str (if (zero? i) "" (substring str 0 i)))
(set! i width))
(else
(string-set! str i (read-input-char))))))))
(else
(do ((c (peek-char input-port) (peek-char input-port))
(l '() (cons c l)))
((or (eof-object? c) (separator? c))
(list->string (reverse l)))
(read-input-char)))))
(define (read-word width separator?)
(let ((l (read-string width separator?)))
(if (zero? (string-length l)) #f l)))
(define (loop1)
(define fc (read-char format-port))
(cond
((eof-object? fc)
(return))
((char-whitespace? fc)
(flush-whitespace format-port)
(flush-whitespace-input)
(loop1))
((eqv? #\% fc) ; interpret next format
(set! fc (read-char format-port))
(let ((report-field? (not (eqv? #\* fc)))
(width #f))
(define (width--) (if width (set! width (+ -1 width))))
(define (read-u)
(string->number (read-string width char-non-numeric?)))
(define (read-o)
(string->number
(read-string
width
(lambda (c)
(not (memv c '(#\0 #\1 #\2 #\3 #\4 #\5 #\6 #\7)))))
8))
(define (read-x)
(string->number
(read-string
width
(lambda (c) (not (memv (char-downcase c)
'(#\0 #\1 #\2 #\3 #\4 #\5 #\6 #\7 #\8
#\9 #\a #\b #\c #\d #\e #\f)))))
16))
(define (read-radixed-unsigned)
(let ((c (peek-char input-port)))
(case c
((#\0) (read-input-char) (width--)
(set! c (peek-char input-port))
(case c
((#\x #\X) (read-input-char) (width--) (read-x))
(else (read-o))))
(else (read-u)))))
(define (read-ui)
(let* ((dot? #f)
(mantissa
(read-word
width
(lambda (c)
(not (or (char-numeric? c)
(cond (dot? #f)
((eqv? #\. c) (set! dot? #t) #t)
(else #f)))))))
(exponent
(cond
((not mantissa) #f)
((and (or (not width) (> width 1))
(memv (peek-char input-port) '(#\E #\e)))
(read-input-char)
(width--)
(let* ((expsign
(case (peek-char input-port)
((#\-) (read-input-char)
(width--) "-")
((#\+) (read-input-char)
(width--) "+")
(else "")))
(expint
(and (or (not width) (positive? width))
(read-word width char-non-numeric?))))
(and expint (string-append "e" expsign expint))))
(else #f))))
(and mantissa
(string->number
(string-append
"#i" (or mantissa "") (or exponent ""))))))
(define (read-signed proc)
(case (peek-char input-port)
((#\-) (read-input-char) (width--)
(let ((ret (proc))) (and ret (- ret))))
((#\+) (read-input-char) (width--) (proc))
(else (proc))))
;;(trace read-word read-signed read-ui read-radixed-unsigned read-x read-o read-u)
(cond ((not report-field?) (set! fc (read-char format-port))))
(if (char-numeric? fc) (set! width 0))
(do () ((or (eof-object? fc) (char-non-numeric? fc)))
(set! width (+ (* 10 width) (string->number (string fc))))
(set! fc (read-char format-port)))
(case fc ;ignore h,l,L modifiers.
((#\h #\l #\L) (set! fc (read-char format-port))))
(case fc
((#\n) (if (not report-field?)
(slib:error 'scanf "not saving %n??"))
(add-item -1 chars-scanned)) ;-1 is special flag.
((#\c #\C)
(if (not width) (set! width 1))
(let ((str (make-string width)))
(do ((i 0 (+ 1 i))
(c (peek-char input-port) (peek-char input-port)))
((or (>= i width)
(eof-object? c))
(add-item report-field? (substring str 0 i)))
(string-set! str i (read-input-char)))))
((#\s #\S)
;;(flush-whitespace-input)
(add-item report-field? (read-word width char-whitespace?)))
((#\[)
(set! fc (read-char format-port))
(let ((allbut #f))
(case fc
((#\^) (set! allbut #t)
(set! fc (read-char format-port))))
(let scanloop ((scanset (list fc)))
(set! fc (read-char format-port))
(case fc
((#\-)
(set! fc (peek-char format-port))
(cond
((and (char<? (car scanset) fc)
(not (eqv? #\] fc)))
(set! fc (char->integer fc))
(do ((i (char->integer (car scanset)) (+ 1 i)))
((> i fc) (scanloop scanset))
(set! scanset (cons (integer->char i) scanset))))
(else (scanloop (cons #\- scanset)))))
((#\])
(add-item report-field?
(read-word
width
(if allbut (lambda (c) (memv c scanset))
(lambda (c) (not (memv c scanset)))))))
(else (cond
((eof-object? fc)
(slib:error 'scanf "unmatched [ in format"))
(else (scanloop (cons fc scanset)))))))))
((#\o #\O)
;;(flush-whitespace-input)
(add-item report-field? (read-o)))
((#\u #\U)
;;(flush-whitespace-input)
(add-item report-field? (read-u)))
((#\d #\D)
;;(flush-whitespace-input)
(add-item report-field? (read-signed read-u)))
((#\x #\X)
;;(flush-whitespace-input)
(add-item report-field? (read-x)))
((#\e #\E #\f #\F #\g #\G)
;;(flush-whitespace-input)
(add-item report-field? (read-signed read-ui)))
((#\i)
;;(flush-whitespace-input)
(add-item report-field? (read-signed read-radixed-unsigned)))
((#\%)
(cond ((or width (not report-field?))
(slib:error 'SCANF "%% has modifiers?"))
((eqv? #\% (read-input-char))
(loop1))
(else (return))))
(else (slib:error 'SCANF
"Unknown format directive:" fc)))))
((eqv? (peek-char input-port) fc)
(read-input-char)
(loop1))
(else (return))))
;;(trace flush-whitespace-input flush-whitespace add-item return read-string read-word loop1)
(loop1))))))
;;;This implements a Scheme-oriented version of SCANF: returns a list of
;;;objects read (rather than set!-ing values).
;@
(define (scanf-read-list format-string . optarg)
(define input-port
(cond ((null? optarg) (current-input-port))
((not (null? (cdr optarg)))
(slib:error 'scanf-read-list 'wrong-number-of-args optarg))
(else (car optarg))))
(cond ((input-port? input-port)
(stdio:scan-and-set format-string input-port #f))
((string? input-port)
(call-with-input-string
input-port (lambda (input-port)
(stdio:scan-and-set format-string input-port #f))))
(else (slib:error 'scanf-read-list "argument 2 not a port"
input-port))))
(define (stdio:setter-procedure sexp)
(let ((v (gentemp)))
(cond ((symbol? sexp) `(lambda (,v) (set! ,sexp ,v) #t))
((not (and (pair? sexp) (list? sexp)))
(slib:error 'scanf "setter expression not understood" sexp))
(else
(case (car sexp)
((vector-ref) `(lambda (,v) (vector-set! ,@(cdr sexp) ,v) #t))
((substring)
`(lambda (,v) (substring-move-left!
,v 0 (min (string-length ,v)
(- ,(cadddr sexp) ,(caddr sexp)))
,(cadr sexp) ,(caddr sexp))
#t))
((list-ref)
`(lambda (,v) (set-car! (list-tail ,@(cdr sexp)) ,v) #t))
((car) `(lambda (,v) (set-car! ,@(cdr sexp) ,v) #t))
((cdr) `(lambda (,v) (set-cdr! ,@(cdr sexp) ,v) #t))
(else (slib:error 'scanf "setter not known" sexp)))))))
;@
(defmacro scanf (format-string . args)
`(stdio:scan-and-set ,format-string (current-input-port)
,@(map stdio:setter-procedure args)))
;@
(defmacro sscanf (str format-string . args)
`(stdio:scan-and-set ,format-string ,str
,@(map stdio:setter-procedure args)))
;@
(defmacro fscanf (input-port format-string . args)
`(stdio:scan-and-set ,format-string ,input-port
,@(map stdio:setter-procedure args)))
|