|
|
#lang debug racket/base
|
|
|
(require racket/class racket/match xenomorph sugar/unstable/dict)
|
|
|
(provide CFFIndex)
|
|
|
|
|
|
(define CFFIndex%
|
|
|
(class x:base%
|
|
|
(super-new)
|
|
|
(init-field [(@type type) #f])
|
|
|
|
|
|
(define (getCFFVersion ctx)
|
|
|
(let loop ([ctx ctx])
|
|
|
(cond
|
|
|
[(and ctx (hash? ctx) (not (hash-ref ctx 'hdrSize #f)))
|
|
|
(loop (hash-ref ctx 'x:parent))]
|
|
|
[(and ctx (hash-ref ctx 'x:version #f))]
|
|
|
[else -1])))
|
|
|
|
|
|
(augride [@decode decode])
|
|
|
(define (@decode stream parent)
|
|
|
(match (decode (if (>= (getCFFVersion parent) 2) uint32be uint16be) stream)
|
|
|
[0 null]
|
|
|
[count (define offSize (decode uint8 stream))
|
|
|
(define offsetType (match offSize
|
|
|
[1 uint8]
|
|
|
[2 uint16be]
|
|
|
[3 uint24be]
|
|
|
[4 uint32be]
|
|
|
[_ (error 'bad-offset-size-in-CFFIndex)]))
|
|
|
(define startPos (+ (pos stream) (* (add1 count) offSize) -1))
|
|
|
(for/fold ([vals null]
|
|
|
[start (decode offsetType stream)]
|
|
|
#:result (begin0 (reverse vals) (pos stream (+ startPos start))))
|
|
|
([i (in-range count)])
|
|
|
(define end (decode offsetType stream))
|
|
|
(define val
|
|
|
(cond
|
|
|
[@type
|
|
|
(define apos (pos stream))
|
|
|
(pos stream (+ startPos start))
|
|
|
(hash-set! parent 'length (- end start))
|
|
|
(begin0
|
|
|
(decode @type stream #:parent parent)
|
|
|
(pos stream apos))]
|
|
|
[else
|
|
|
(hasheq 'offset (+ startPos start)
|
|
|
'length (- end start))]))
|
|
|
(values (cons val vals) end))]))
|
|
|
|
|
|
(augride [@size size])
|
|
|
(define (@size arr parent)
|
|
|
#RRR 'in-cfff-index-size
|
|
|
(define size 2)
|
|
|
(cond
|
|
|
[(zero? (length arr)) size]
|
|
|
[else
|
|
|
(define type (or #RR @type (x:buffer)))
|
|
|
#RR type
|
|
|
|
|
|
;; find maximum offset to determinine offset type
|
|
|
(define offset 1)
|
|
|
(for ([(item i) (in-indexed arr)])
|
|
|
(set! offset (+ offset (send type size item parent))))
|
|
|
|
|
|
(define offsetType
|
|
|
(cond
|
|
|
[(<= offset #xff) uint8]
|
|
|
[(<= offset #xffff) uint16be]
|
|
|
[(<= offset #xffffff) uint24be]
|
|
|
[(<= offset #xffffffff) uint32be]
|
|
|
[else (error 'CFFIndex-size (format "bad offset: ~a" offset))]))
|
|
|
|
|
|
(set! size (+ size 1 (* (send offsetType size) (add1 (length arr)))))
|
|
|
(set! size (+ size (sub1 offset)))
|
|
|
|
|
|
size]))
|
|
|
|
|
|
(define/augride (encode arr stream parent)
|
|
|
(error 'cff-index-encode-not-implemented))))
|
|
|
|
|
|
(define (CFFIndex [type #f])
|
|
|
(new CFFIndex% [type type])) |