24 lines
546 B
Racket
24 lines
546 B
Racket
#lang racket/base
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(require ffi/unsafe)
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; set up access to racket internals
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(define scheme-malloc-code
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(get-ffi-obj 'scheme_malloc_code #f (_fun (len : _intptr) -> _pointer)))
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(define scheme-free-code
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(get-ffi-obj 'scheme_free_code #f (_fun _pointer -> _void)))
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(define opcodes '(139 68 36 4 3 68 36 8 195))
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(define code (scheme-malloc-code 64))
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(for ([byte opcodes]
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[i (in-naturals)])
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(ptr-set! code _ubyte i byte))
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(define function (cast code _pointer (_fun _ubyte _ubyte -> _ubyte)))
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(function 7 12)
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(scheme-free-code code)
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