@@ 371,17 371,25 @@ all subject to the substitutions."
;;; Patching shebangs---e.g., /bin/sh -> /nix/store/xyz...-bash/bin/sh.
;;;
-(define* (dump-port in out #:key (buffer-size 16384))
+(define* (dump-port in out
+ #:key (buffer-size 16384)
+ (progress (lambda (t k) (k))))
"Read as much data as possible from IN and write it to OUT, using
-chunks of BUFFER-SIZE bytes."
+chunks of BUFFER-SIZE bytes. Call PROGRESS after each successful
+transfer of BUFFER-SIZE bytes or less, passing it the total number of
+bytes transferred and the continuation of the transfer as a thunk."
(define buffer
(make-bytevector buffer-size))
- (let loop ((bytes (get-bytevector-n! in buffer 0 buffer-size)))
+ (let loop ((total 0)
+ (bytes (get-bytevector-n! in buffer 0 buffer-size)))
(or (eof-object? bytes)
- (begin
+ (let ((total (+ total bytes)))
(put-bytevector out buffer 0 bytes)
- (loop (get-bytevector-n! in buffer 0 buffer-size))))))
+ (progress total
+ (lambda ()
+ (loop total
+ (get-bytevector-n! in buffer 0 buffer-size))))))))
(define patch-shebang
(let ((shebang-rx (make-regexp "^[[:blank:]]*([[:graph:]]+)(.*)$")))