guix-devel/guix/scripts/substitute-binary.scm

776 lines
31 KiB
Scheme
Executable File
Raw Blame History

This file contains invisible Unicode characters

This file contains invisible Unicode characters that are indistinguishable to humans but may be processed differently by a computer. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

;;; GNU Guix --- Functional package management for GNU
;;; Copyright © 2013, 2014 Ludovic Courtès <ludo@gnu.org>
;;; Copyright © 2014 Nikita Karetnikov <nikita@karetnikov.org>
;;;
;;; This file is part of GNU Guix.
;;;
;;; GNU Guix is free software; you can redistribute it and/or modify it
;;; under the terms of the GNU General Public License as published by
;;; the Free Software Foundation; either version 3 of the License, or (at
;;; your option) any later version.
;;;
;;; GNU Guix is distributed in the hope that it will be useful, but
;;; WITHOUT ANY WARRANTY; without even the implied warranty of
;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
;;; GNU General Public License for more details.
;;;
;;; You should have received a copy of the GNU General Public License
;;; along with GNU Guix. If not, see <http://www.gnu.org/licenses/>.
(define-module (guix scripts substitute-binary)
#:use-module (guix ui)
#:use-module (guix store)
#:use-module (guix utils)
#:use-module (guix config)
#:use-module (guix records)
#:use-module (guix serialization)
#:use-module (guix hash)
#:use-module (guix base64)
#:use-module (guix pk-crypto)
#:use-module (guix pki)
#:use-module ((guix build utils) #:select (mkdir-p))
#:use-module ((guix build download)
#:select (progress-proc uri-abbreviation))
#:use-module (ice-9 rdelim)
#:use-module (ice-9 regex)
#:use-module (ice-9 match)
#:use-module (ice-9 threads)
#:use-module (ice-9 format)
#:use-module (ice-9 ftw)
#:use-module (ice-9 binary-ports)
#:use-module (rnrs io ports)
#:use-module (rnrs bytevectors)
#:use-module (srfi srfi-1)
#:use-module (srfi srfi-9)
#:use-module (srfi srfi-11)
#:use-module (srfi srfi-19)
#:use-module (srfi srfi-26)
#:use-module (srfi srfi-34)
#:use-module (srfi srfi-35)
#:use-module (web uri)
#:use-module (guix http-client)
#:export (narinfo-signature->canonical-sexp
read-narinfo
write-narinfo
guix-substitute-binary))
;;; Comment:
;;;
;;; This is the "binary substituter". It is invoked by the daemon do check
;;; for the existence of available "substitutes" (pre-built binaries), and to
;;; actually use them as a substitute to building things locally.
;;;
;;; If possible, substitute a binary for the requested store path, using a Nix
;;; "binary cache". This program implements the Nix "substituter" protocol.
;;;
;;; Code:
(define %narinfo-cache-directory
;; A local cache of narinfos, to avoid going to the network.
(or (and=> (getenv "XDG_CACHE_HOME")
(cut string-append <> "/guix/substitute-binary"))
(string-append %state-directory "/substitute-binary/cache")))
(define %allow-unauthenticated-substitutes?
;; Whether to allow unchecked substitutes. This is useful for testing
;; purposes, and should be avoided otherwise.
(and (and=> (getenv "GUIX_ALLOW_UNAUTHENTICATED_SUBSTITUTES")
(cut string-ci=? <> "yes"))
(begin
(warning (_ "authentication and authorization of substitutes \
disabled!~%"))
#t)))
(define %narinfo-ttl
;; Number of seconds during which cached narinfo lookups are considered
;; valid.
(* 24 3600))
(define %narinfo-negative-ttl
;; Likewise, but for negative lookups---i.e., cached lookup failures.
(* 3 3600))
(define %narinfo-expired-cache-entry-removal-delay
;; How often we want to remove files corresponding to expired cache entries.
(* 7 24 3600))
;; In Guile 2.0.9, `regexp-exec' is thread-unsafe, so work around it.
;; See <http://bugs.gnu.org/14404>.
(set! regexp-exec
(let ((real regexp-exec)
(lock (make-mutex)))
(lambda (rx str . rest)
(with-mutex lock
(apply real rx str rest)))))
(define fields->alist
;; The narinfo format is really just like recutils.
recutils->alist)
(define %fetch-timeout
;; Number of seconds after which networking is considered "slow".
5)
(define %random-state
(seed->random-state (+ (ash (cdr (gettimeofday)) 32) (getpid))))
(define-syntax-rule (with-timeout duration handler body ...)
"Run BODY; when DURATION seconds have expired, call HANDLER, and run BODY
again."
(begin
(sigaction SIGALRM
(lambda (signum)
(sigaction SIGALRM SIG_DFL)
handler))
(alarm duration)
(call-with-values
(lambda ()
(let try ()
(catch 'system-error
(lambda ()
body ...)
(lambda args
;; Before Guile v2.0.9-39-gfe51c7b, the SIGALRM triggers EINTR
;; because of the bug at
;; <http://lists.gnu.org/archive/html/guile-devel/2013-06/msg00050.html>.
;; When that happens, try again. Note: SA_RESTART cannot be
;; used because of <http://bugs.gnu.org/14640>.
(if (= EINTR (system-error-errno args))
(begin
;; Wait a little to avoid bursts.
(usleep (random 3000000 %random-state))
(try))
(apply throw args))))))
(lambda result
(alarm 0)
(sigaction SIGALRM SIG_DFL)
(apply values result)))))
(define* (fetch uri #:key (buffered? #t) (timeout? #t) (quiet-404? #f))
"Return a binary input port to URI and the number of bytes it's expected to
provide. If QUIET-404? is true, HTTP 404 error conditions are passed through
to the caller without emitting an error message."
(case (uri-scheme uri)
((file)
(let ((port (open-file (uri-path uri)
(if buffered? "rb" "r0b"))))
(values port (stat:size (stat port)))))
((http)
(guard (c ((http-get-error? c)
(let ((code (http-get-error-code c)))
(if (and (= code 404) quiet-404?)
(raise c)
(leave (_ "download from '~a' failed: ~a, ~s~%")
(uri->string (http-get-error-uri c))
code (http-get-error-reason c))))))
;; On Guile 2.0.5, `http-fetch' fetches the whole thing at once. So
;; honor TIMEOUT? to disable the timeout when fetching a nar.
;;
;; Test this with:
;; sudo tc qdisc add dev eth0 root netem delay 1500ms
;; and then cancel with:
;; sudo tc qdisc del dev eth0 root
(let ((port #f))
(with-timeout (if (or timeout? (guile-version>? "2.0.5"))
%fetch-timeout
0)
(begin
(warning (_ "while fetching ~a: server is somewhat slow~%")
(uri->string uri))
(warning (_ "try `--no-substitutes' if the problem persists~%"))
;; Before Guile v2.0.9-39-gfe51c7b, EINTR was reported to the user,
;; and thus PORT had to be closed and re-opened. This is not the
;; case afterward.
(unless (or (guile-version>? "2.0.9")
(version>? (version) "2.0.9.39"))
(when port
(close-port port))))
(begin
(when (or (not port) (port-closed? port))
(set! port (open-socket-for-uri uri #:buffered? buffered?)))
(http-fetch uri #:text? #f #:port port))))))))
(define-record-type <cache>
(%make-cache url store-directory wants-mass-query?)
cache?
(url cache-url)
(store-directory cache-store-directory)
(wants-mass-query? cache-wants-mass-query?))
(define (open-cache url)
"Open the binary cache at URL. Return a <cache> object on success, or #f on
failure."
(define (download-cache-info url)
;; Download the `nix-cache-info' from URL, and return its contents as an
;; list of key/value pairs.
(and=> (false-if-exception (fetch (string->uri url)))
fields->alist))
(and=> (download-cache-info (string-append url "/nix-cache-info"))
(lambda (properties)
(alist->record properties
(cut %make-cache url <...>)
'("StoreDir" "WantMassQuery")))))
(define-record-type <narinfo>
(%make-narinfo path uri uri-base compression file-hash file-size nar-hash nar-size
references deriver system signature contents)
narinfo?
(path narinfo-path)
(uri narinfo-uri)
(uri-base narinfo-uri-base) ; URI of the cache it originates from
(compression narinfo-compression)
(file-hash narinfo-file-hash)
(file-size narinfo-file-size)
(nar-hash narinfo-hash)
(nar-size narinfo-size)
(references narinfo-references)
(deriver narinfo-deriver)
(system narinfo-system)
(signature narinfo-signature) ; canonical sexp
;; The original contents of a narinfo file. This field is needed because we
;; want to preserve the exact textual representation for verification purposes.
;; See <https://lists.gnu.org/archive/html/guix-devel/2014-02/msg00340.html>
;; for more information.
(contents narinfo-contents))
(define (narinfo-signature->canonical-sexp str)
"Return the value of a narinfo's 'Signature' field as a canonical sexp."
(match (string-split str #\;)
((version _ sig)
(let ((maybe-number (string->number version)))
(cond ((not (number? maybe-number))
(leave (_ "signature version must be a number: ~s~%")
version))
;; Currently, there are no other versions.
((not (= 1 maybe-number))
(leave (_ "unsupported signature version: ~a~%")
maybe-number))
(else
(let ((signature (utf8->string (base64-decode sig))))
(catch 'gcry-error
(lambda ()
(string->canonical-sexp signature))
(lambda (key proc err)
(leave (_ "signature is not a valid \
s-expression: ~s~%")
signature))))))))
(x
(leave (_ "invalid format of the signature field: ~a~%") x))))
(define (narinfo-maker str cache-url)
"Return a narinfo constructor for narinfos originating from CACHE-URL. STR
must contain the original contents of a narinfo file."
(lambda (path url compression file-hash file-size nar-hash nar-size
references deriver system signature)
"Return a new <narinfo> object."
(%make-narinfo path
;; Handle the case where URL is a relative URL.
(or (string->uri url)
(string->uri (string-append cache-url "/" url)))
cache-url
compression file-hash
(and=> file-size string->number)
nar-hash
(and=> nar-size string->number)
(string-tokenize references)
(match deriver
((or #f "") #f)
(_ deriver))
system
(false-if-exception
(and=> signature narinfo-signature->canonical-sexp))
str)))
(define* (assert-valid-signature narinfo signature hash
#:optional (acl (current-acl)))
"Bail out if SIGNATURE, a canonical sexp representing the signature of
NARINFO, doesn't match HASH, a bytevector containing the hash of NARINFO."
(let ((uri (uri->string (narinfo-uri narinfo))))
(signature-case (signature hash acl)
(valid-signature #t)
(invalid-signature
(leave (_ "invalid signature for '~a'~%") uri))
(hash-mismatch
(leave (_ "hash mismatch for '~a'~%") uri))
(unauthorized-key
(leave (_ "'~a' is signed with an unauthorized key~%") uri))
(corrupt-signature
(leave (_ "signature on '~a' is corrupt~%") uri)))))
(define* (read-narinfo port #:optional url)
"Read a narinfo from PORT. If URL is true, it must be a string used to
build full URIs from relative URIs found while reading PORT.
No authentication and authorization checks are performed here!"
(let ((str (utf8->string (get-bytevector-all port))))
(alist->record (call-with-input-string str fields->alist)
(narinfo-maker str url)
'("StorePath" "URL" "Compression"
"FileHash" "FileSize" "NarHash" "NarSize"
"References" "Deriver" "System"
"Signature"))))
(define (narinfo-sha256 narinfo)
"Return the sha256 hash of NARINFO as a bytevector, or #f if NARINFO lacks a
'Signature' field."
(let ((contents (narinfo-contents narinfo)))
(match (string-contains contents "Signature:")
(#f #f)
(index
(let ((above-signature (string-take contents index)))
(sha256 (string->utf8 above-signature)))))))
(define* (assert-valid-narinfo narinfo
#:optional (acl (current-acl))
#:key (verbose? #t))
"Raise an exception if NARINFO lacks a signature, has an invalid signature,
or is signed by an unauthorized key."
(let ((hash (narinfo-sha256 narinfo)))
(if (not hash)
(if %allow-unauthenticated-substitutes?
narinfo
(leave (_ "substitute at '~a' lacks a signature~%")
(uri->string (narinfo-uri narinfo))))
(let ((signature (narinfo-signature narinfo)))
(unless %allow-unauthenticated-substitutes?
(assert-valid-signature narinfo signature hash acl)
(when verbose?
(format (current-error-port)
"found valid signature for '~a', from '~a'~%"
(narinfo-path narinfo)
(uri->string (narinfo-uri narinfo)))))
narinfo))))
(define* (valid-narinfo? narinfo #:optional (acl (current-acl)))
"Return #t if NARINFO's signature is not valid."
(or %allow-unauthenticated-substitutes?
(let ((hash (narinfo-sha256 narinfo))
(signature (narinfo-signature narinfo)))
(and hash signature
(signature-case (signature hash acl)
(valid-signature #t)
(else #f))))))
(define (write-narinfo narinfo port)
"Write NARINFO to PORT."
(put-bytevector port (string->utf8 (narinfo-contents narinfo))))
(define (narinfo->string narinfo)
"Return the external representation of NARINFO."
(call-with-output-string (cut write-narinfo narinfo <>)))
(define (string->narinfo str cache-uri)
"Return the narinfo represented by STR. Assume CACHE-URI as the base URI of
the cache STR originates form."
(call-with-input-string str (cut read-narinfo <> cache-uri)))
(define (fetch-narinfo cache path)
"Return the <narinfo> record for PATH, or #f if CACHE does not hold PATH."
(define (download url)
;; Download the .narinfo from URL, and return its contents as a list of
;; key/value pairs. Don't emit an error message upon 404.
(false-if-exception (fetch (string->uri url)
#:quiet-404? #t)))
(and (string=? (cache-store-directory cache) (%store-prefix))
(and=> (download (string-append (cache-url cache) "/"
(store-path-hash-part path)
".narinfo"))
(cute read-narinfo <> (cache-url cache)))))
(define (obsolete? date now ttl)
"Return #t if DATE is obsolete compared to NOW + TTL seconds."
(time>? (subtract-duration now (make-time time-duration 0 ttl))
(make-time time-monotonic 0 date)))
(define %lookup-threads
;; Number of threads spawned to perform lookup operations. This means we
;; can have this many simultaneous HTTP GET requests to the server, which
;; limits the impact of connection latency.
20)
(define (lookup-narinfo cache path)
"Check locally if we have valid info about PATH, otherwise go to CACHE and
check what it has."
(define now
(current-time time-monotonic))
(define cache-file
(string-append %narinfo-cache-directory "/"
(store-path-hash-part path)))
(define (cache-entry cache-uri narinfo)
`(narinfo (version 1)
(cache-uri ,cache-uri)
(date ,(time-second now))
(value ,(and=> narinfo narinfo->string))))
(let*-values (((valid? cached)
(catch 'system-error
(lambda ()
(call-with-input-file cache-file
(lambda (p)
(match (read p)
(('narinfo ('version 1)
('cache-uri cache-uri)
('date date) ('value #f))
;; A cached negative lookup.
(if (obsolete? date now %narinfo-negative-ttl)
(values #f #f)
(values #t #f)))
(('narinfo ('version 1)
('cache-uri cache-uri)
('date date) ('value value))
;; A cached positive lookup
(if (obsolete? date now %narinfo-ttl)
(values #f #f)
(values #t (string->narinfo value
cache-uri))))
(('narinfo ('version v) _ ...)
(values #f #f))))))
(lambda _
(values #f #f)))))
(if valid?
cached ; including negative caches
(let* ((cache (force cache))
(narinfo (and cache (fetch-narinfo cache path))))
;; Cache NARINFO only when CACHE was actually accessible. This
;; avoids caching negative hits when in fact we just lacked network
;; access.
(when cache
(with-atomic-file-output cache-file
(lambda (out)
(write (cache-entry (cache-url cache) narinfo) out))))
narinfo))))
(define (remove-expired-cached-narinfos)
"Remove expired narinfo entries from the cache. The sole purpose of this
function is to make sure `%narinfo-cache-directory' doesn't grow
indefinitely."
(define now
(current-time time-monotonic))
(define (expired? file)
(catch 'system-error
(lambda ()
(call-with-input-file file
(lambda (port)
(match (read port)
(('narinfo ('version 1) ('cache-uri _) ('date date)
('value #f))
(obsolete? date now %narinfo-negative-ttl))
(('narinfo ('version 1) ('cache-uri _) ('date date)
('value _))
(obsolete? date now %narinfo-ttl))
(_ #t)))))
(lambda args
;; FILE may have been deleted.
#t)))
(for-each (lambda (file)
(let ((file (string-append %narinfo-cache-directory
"/" file)))
(when (expired? file)
;; Wrap in `false-if-exception' because FILE might have been
;; deleted in the meantime (TOCTTOU).
(false-if-exception (delete-file file)))))
(scandir %narinfo-cache-directory
(lambda (file)
(= (string-length file) 32)))))
(define (maybe-remove-expired-cached-narinfo)
"Remove expired narinfo entries from the cache if deemed necessary."
(define now
(current-time time-monotonic))
(define expiry-file
(string-append %narinfo-cache-directory "/last-expiry-cleanup"))
(define last-expiry-date
(or (false-if-exception
(call-with-input-file expiry-file read))
0))
(when (obsolete? last-expiry-date now %narinfo-expired-cache-entry-removal-delay)
(remove-expired-cached-narinfos)
(call-with-output-file expiry-file
(cute write (time-second now) <>))))
(define (progress-report-port report-progress port)
"Return a port that calls REPORT-PROGRESS every time something is read from
PORT. REPORT-PROGRESS is a two-argument procedure such as that returned by
`progress-proc'."
(define total 0)
(define (read! bv start count)
(let ((n (match (get-bytevector-n! port bv start count)
((? eof-object?) 0)
(x x))))
(set! total (+ total n))
(report-progress total (const n))
;; XXX: We're not in control, so we always return anyway.
n))
;; Since `http-fetch' in Guile 2.0.5 returns all the data once it's done,
;; don't pretend to report any progress in that case.
(if (guile-version>? "2.0.5")
(make-custom-binary-input-port "progress-port-proc"
read! #f #f
(cut close-port port))
(begin
(format (current-error-port) (_ "Downloading, please wait...~%"))
(format (current-error-port)
(_ "(Please consider upgrading Guile to get proper progress report.)~%"))
port)))
(define-syntax with-networking
(syntax-rules ()
"Catch DNS lookup errors and gracefully exit."
;; Note: no attempt is made to catch other networking errors, because DNS
;; lookup errors are typically the first one, and because other errors are
;; a subset of `system-error', which is harder to filter.
((_ exp ...)
(catch 'getaddrinfo-error
(lambda () exp ...)
(lambda (key error)
(leave (_ "host name lookup error: ~a~%")
(gai-strerror error)))))))
;;;
;;; Help.
;;;
(define (show-help)
(display (_ "Usage: guix substitute-binary [OPTION]...
Internal tool to substitute a pre-built binary to a local build.\n"))
(display (_ "
--query report on the availability of substitutes for the
store file names passed on the standard input"))
(display (_ "
--substitute STORE-FILE DESTINATION
download STORE-FILE and store it as a Nar in file
DESTINATION"))
(newline)
(display (_ "
-h, --help display this help and exit"))
(display (_ "
-V, --version display version information and exit"))
(newline)
(show-bug-report-information))
;;;
;;; Entry point.
;;;
(define n-par-map*
;; We want the ability to run many threads in parallel, regardless of the
;; number of cores. However, Guile 2.0.5 has a bug whereby 'n-par-map' ends
;; up consuming a lot of memory, possibly leading to death. Thus, resort to
;; 'par-map' on 2.0.5.
(if (guile-version>? "2.0.5")
n-par-map
(lambda (n proc lst)
(par-map proc lst))))
(define (check-acl-initialized)
"Warn if the ACL is uninitialized."
(define (singleton? acl)
;; True if ACL contains just the user's public key.
(and (file-exists? %public-key-file)
(let ((key (call-with-input-file %public-key-file
(compose string->canonical-sexp
get-string-all))))
(match acl
((thing)
(equal? (canonical-sexp->string thing)
(canonical-sexp->string key)))
(_
#f)))))
(let ((acl (acl->public-keys (current-acl))))
(when (or (null? acl) (singleton? acl))
(warning (_ "ACL for archive imports seems to be uninitialized, \
substitutes may be unavailable\n")))))
(define (daemon-options)
"Return a list of name/value pairs denoting build daemon options."
(define %not-newline
(char-set-complement (char-set #\newline)))
(match (getenv "_NIX_OPTIONS")
(#f ;should not happen when called by the daemon
'())
(newline-separated
;; Here we get something of the form "OPTION1=VALUE1\nOPTION2=VALUE2\n".
(filter-map (lambda (option=value)
(match (string-index option=value #\=)
(#f ;invalid option setting
#f)
(equal-sign
(cons (string-take option=value equal-sign)
(string-drop option=value (+ 1 equal-sign))))))
(string-tokenize newline-separated %not-newline)))))
(define (find-daemon-option option)
"Return the value of build daemon option OPTION, or #f if it could not be
found."
(assoc-ref (daemon-options) option))
(define %cache-url
(match (and=> (find-daemon-option "substitute-urls")
string-tokenize)
((url)
url)
((head tail ..1)
;; Currently we don't handle multiple substitute URLs.
(warning (_ "these substitute URLs will not be used:~{ ~a~}~%")
tail)
head)
(#f
;; This can only happen when this script is not invoked by the
;; daemon.
"http://hydra.gnu.org")))
(define (guix-substitute-binary . args)
"Implement the build daemon's substituter protocol."
(mkdir-p %narinfo-cache-directory)
(maybe-remove-expired-cached-narinfo)
(check-acl-initialized)
;; Starting from commit 22144afa in Nix, we are allowed to bail out directly
;; when we know we cannot substitute, but we must emit a newline on stdout
;; when everything is alright.
(let ((uri (string->uri %cache-url)))
(case (uri-scheme uri)
((http)
;; Exit gracefully if there's no network access.
(let ((host (uri-host uri)))
(catch 'getaddrinfo-error
(lambda ()
(getaddrinfo host))
(lambda (key error)
(warning (_ "failed to look up host '~a' (~a), \
substituter disabled~%")
host (gai-strerror error))
(exit 0)))))
(else #t)))
;; Say hello (see above.)
(newline)
(force-output (current-output-port))
(with-networking
(with-error-handling ; for signature errors
(match args
(("--query")
(let ((cache (delay (open-cache %cache-url)))
(acl (current-acl)))
(define (valid? obj)
(and (narinfo? obj) (valid-narinfo? obj acl)))
(let loop ((command (read-line)))
(or (eof-object? command)
(begin
(match (string-tokenize command)
(("have" paths ..1)
;; Return the subset of PATHS available in CACHE.
(let ((substitutable
(if cache
(n-par-map* %lookup-threads
(cut lookup-narinfo cache <>)
paths)
'())))
(for-each (lambda (narinfo)
(format #t "~a~%" (narinfo-path narinfo)))
(filter valid? substitutable))
(newline)))
(("info" paths ..1)
;; Reply info about PATHS if it's in CACHE.
(let ((substitutable
(if cache
(n-par-map* %lookup-threads
(cut lookup-narinfo cache <>)
paths)
'())))
(for-each (lambda (narinfo)
(format #t "~a\n~a\n~a\n"
(narinfo-path narinfo)
(or (and=> (narinfo-deriver narinfo)
(cute string-append
(%store-prefix) "/"
<>))
"")
(length (narinfo-references narinfo)))
(for-each (cute format #t "~a/~a~%"
(%store-prefix) <>)
(narinfo-references narinfo))
(format #t "~a\n~a\n"
(or (narinfo-file-size narinfo) 0)
(or (narinfo-size narinfo) 0)))
(filter valid? substitutable))
(newline)))
(wtf
(error "unknown `--query' command" wtf)))
(loop (read-line)))))))
(("--substitute" store-path destination)
;; Download STORE-PATH and add store it as a Nar in file DESTINATION.
(let* ((cache (delay (open-cache %cache-url)))
(narinfo (lookup-narinfo cache store-path))
(uri (narinfo-uri narinfo)))
;; Make sure it is signed and everything.
(assert-valid-narinfo narinfo)
;; Tell the daemon what the expected hash of the Nar itself is.
(format #t "~a~%" (narinfo-hash narinfo))
(format (current-error-port) "downloading `~a'~:[~*~; (~,1f MiB installed)~]...~%"
store-path
;; Use the Nar size as an estimate of the installed size.
(narinfo-size narinfo)
(and=> (narinfo-size narinfo)
(cute / <> (expt 2. 20))))
(let*-values (((raw download-size)
;; Note that Hydra currently generates Nars on the fly
;; and doesn't specify a Content-Length, so
;; DOWNLOAD-SIZE is #f in practice.
(fetch uri #:buffered? #f #:timeout? #f))
((progress)
(let* ((comp (narinfo-compression narinfo))
(dl-size (or download-size
(and (equal? comp "none")
(narinfo-size narinfo))))
(progress (progress-proc (uri-abbreviation uri)
dl-size
(current-error-port))))
(progress-report-port progress raw)))
((input pids)
(decompressed-port (and=> (narinfo-compression narinfo)
string->symbol)
progress)))
;; Unpack the Nar at INPUT into DESTINATION.
(restore-file input destination)
;; Skip a line after what 'progress-proc' printed.
(newline (current-error-port))
(every (compose zero? cdr waitpid) pids))))
(("--version")
(show-version-and-exit "guix substitute-binary"))
(("--help")
(show-help))
(opts
(leave (_ "~a: unrecognized options~%") opts))))))
;;; Local Variables:
;;; eval: (put 'with-timeout 'scheme-indent-function 1)
;;; End:
;;; substitute-binary.scm ends here