I'd like to take an input-port that I know has gzip encoded bytes, and
return a new input-port port that will return the decoded bytes. I
don't want to suck the entire bytes into memory. Instead I want to
"stream" them as-needed.
It _seems_ like I could do this is with a combination of `make-pipe`
and `gunzip-through-ports`.
But at the end, instead of getting `eof` the program hangs.
Does anyone see what I'm doing wrong?
#lang racket
(require file/gzip
file/gunzip)
(provide gzip/bytes
gunzip/bytes
make-gzip-decoding-input-port
make-gzip-encoding-input-port)
(define (gzip/bytes b)
(define in (open-input-bytes b))
(define out (open-output-bytes))
(gzip-through-ports in out #f 0)
(get-output-bytes out))
(define (gunzip/bytes b)
(define in (open-input-bytes b))
(define out (open-output-bytes))
(gunzip-through-ports in out)
(get-output-bytes out))
(module+ test
(require rackunit)
(let ([b #"0123456789"])
(check-equal? (gunzip/bytes (gzip/bytes b)) b)))
(define (make-gzip-encoding-input-port in [limit #f])
(define-values (pin pout) (make-pipe limit 'gzip-pipe 'gzip-pipe))
(thread (lambda () (gzip-through-ports in pout)))
pin)
(define (make-gzip-decoding-input-port in [limit #f])
(define-values (pin pout) (make-pipe limit 'gunzip-pipe 'gunzip-pipe))
(thread (lambda () (gunzip-through-ports in pout)))
pin)
;; Try to use:
(define b (gzip/bytes #"abcde"))
(define in0 (open-input-bytes b))
(define in (make-gzip-decoding-input-port in0))
(read-bytes 5 in) ; => #"abcde"
(read-bytes 1 in) ; => hangs here (expected it to return `eof`)
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