717 lines
26 KiB
Scheme
717 lines
26 KiB
Scheme
;;; GNU Guix --- Functional package management for GNU
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;;; Copyright © 2012, 2013, 2014, 2015 Ludovic Courtès <ludo@gnu.org>
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;;; Copyright © 2013, 2014, 2015 Mark H Weaver <mhw@netris.org>
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;;; Copyright © 2014 Eric Bavier <bavier@member.fsf.org>
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;;; Copyright © 2014 Ian Denhardt <ian@zenhack.net>
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;;;
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;;; This file is part of GNU Guix.
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;;;
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;;; GNU Guix is free software; you can redistribute it and/or modify it
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;;; under the terms of the GNU General Public License as published by
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;;; the Free Software Foundation; either version 3 of the License, or (at
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;;; your option) any later version.
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;;;
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;;; GNU Guix is distributed in the hope that it will be useful, but
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;;; WITHOUT ANY WARRANTY; without even the implied warranty of
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;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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;;; GNU General Public License for more details.
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;;;
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;;; You should have received a copy of the GNU General Public License
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;;; along with GNU Guix. If not, see <http://www.gnu.org/licenses/>.
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(define-module (guix utils)
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#:use-module (guix config)
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#:use-module (srfi srfi-1)
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#:use-module (srfi srfi-9)
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#:use-module (srfi srfi-11)
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#:use-module (srfi srfi-26)
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#:use-module (srfi srfi-39)
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#:use-module (srfi srfi-60)
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#:use-module (rnrs bytevectors)
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#:use-module ((rnrs io ports) #:select (put-bytevector))
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#:use-module ((guix build utils)
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#:select (dump-port package-name->name+version))
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#:use-module ((guix build syscalls) #:select (errno mkdtemp!))
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#:use-module (ice-9 vlist)
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#:use-module (ice-9 format)
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#:autoload (ice-9 popen) (open-pipe*)
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#:autoload (ice-9 rdelim) (read-line)
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#:use-module (ice-9 regex)
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#:use-module (ice-9 match)
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#:use-module (ice-9 format)
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#:use-module (system foreign)
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#:re-export (package-name->name+version)
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#:export (bytevector->base16-string
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base16-string->bytevector
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compile-time-value
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fcntl-flock
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memoize
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strip-keyword-arguments
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default-keyword-arguments
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substitute-keyword-arguments
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<location>
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location
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location?
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location-file
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location-line
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location-column
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source-properties->location
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nix-system->gnu-triplet
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gnu-triplet->nix-system
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%current-system
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%current-target-system
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version-compare
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version>?
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version>=?
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version-prefix
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version-major+minor
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guile-version>?
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string-replace-substring
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arguments-from-environment-variable
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file-extension
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file-sans-extension
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call-with-temporary-output-file
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call-with-temporary-directory
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with-atomic-file-output
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fold2
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fold-tree
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fold-tree-leaves
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filtered-port
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compressed-port
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decompressed-port
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call-with-decompressed-port
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compressed-output-port
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call-with-compressed-output-port))
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;;;
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;;; Compile-time computations.
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;;;
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(define-syntax compile-time-value
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(syntax-rules ()
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"Evaluate the given expression at compile time. The expression must
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evaluate to a simple datum."
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((_ exp)
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(let-syntax ((v (lambda (s)
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(let ((val exp))
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(syntax-case s ()
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(_ #`'#,(datum->syntax s val)))))))
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v))))
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;;;
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;;; Base 16.
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;;;
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(define (bytevector->base16-string bv)
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"Return the hexadecimal representation of BV's contents."
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(define len
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(bytevector-length bv))
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(let-syntax ((base16-chars (lambda (s)
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(syntax-case s ()
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(_
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(let ((v (list->vector
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(unfold (cut > <> 255)
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(lambda (n)
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(format #f "~2,'0x" n))
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1+
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0))))
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v))))))
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(define chars base16-chars)
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(let loop ((i len)
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(r '()))
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(if (zero? i)
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(string-concatenate r)
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(let ((i (- i 1)))
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(loop i
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(cons (vector-ref chars (bytevector-u8-ref bv i)) r)))))))
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(define base16-string->bytevector
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(let ((chars->value (fold (lambda (i r)
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(vhash-consv (string-ref (number->string i 16)
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0)
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i r))
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vlist-null
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(iota 16))))
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(lambda (s)
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"Return the bytevector whose hexadecimal representation is string S."
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(define bv
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(make-bytevector (quotient (string-length s) 2) 0))
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(string-fold (lambda (chr i)
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(let ((j (quotient i 2))
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(v (and=> (vhash-assv chr chars->value) cdr)))
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(if v
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(if (zero? (logand i 1))
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(bytevector-u8-set! bv j
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(arithmetic-shift v 4))
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(let ((w (bytevector-u8-ref bv j)))
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(bytevector-u8-set! bv j (logior v w))))
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(error "invalid hexadecimal character" chr)))
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(+ i 1))
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0
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s)
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bv)))
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;;;
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;;; Filtering & pipes.
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;;;
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(define (filtered-port command input)
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"Return an input port where data drained from INPUT is filtered through
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COMMAND (a list). In addition, return a list of PIDs that the caller must
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wait. When INPUT is a file port, it must be unbuffered; otherwise, any
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buffered data is lost."
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(let loop ((input input)
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(pids '()))
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(if (file-port? input)
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(match (pipe)
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((in . out)
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(match (primitive-fork)
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(0
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(dynamic-wind
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(const #f)
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(lambda ()
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(close-port in)
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(close-port (current-input-port))
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(dup2 (fileno input) 0)
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(close-port (current-output-port))
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(dup2 (fileno out) 1)
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(catch 'system-error
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(lambda ()
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(apply execl (car command) command))
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(lambda args
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(format (current-error-port)
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"filtered-port: failed to execute '~{~a ~}': ~a~%"
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command (strerror (system-error-errno args))))))
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(lambda ()
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(primitive-_exit 1))))
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(child
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(close-port out)
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(values in (cons child pids))))))
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;; INPUT is not a file port, so fork just for the sake of tunneling it
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;; through a file port.
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(match (pipe)
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((in . out)
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(match (primitive-fork)
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(0
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(dynamic-wind
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(const #t)
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(lambda ()
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(close-port in)
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(dump-port input out))
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(lambda ()
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(false-if-exception (close out))
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(primitive-_exit 0))))
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(child
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(close-port out)
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(loop in (cons child pids)))))))))
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(define (decompressed-port compression input)
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"Return an input port where INPUT is decompressed according to COMPRESSION,
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a symbol such as 'xz."
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(match compression
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((or #f 'none) (values input '()))
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('bzip2 (filtered-port `(,%bzip2 "-dc") input))
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('xz (filtered-port `(,%xz "-dc") input))
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('gzip (filtered-port `(,%gzip "-dc") input))
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(else (error "unsupported compression scheme" compression))))
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(define (compressed-port compression input)
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"Return an input port where INPUT is decompressed according to COMPRESSION,
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a symbol such as 'xz."
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(match compression
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((or #f 'none) (values input '()))
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('bzip2 (filtered-port `(,%bzip2 "-c") input))
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('xz (filtered-port `(,%xz "-c") input))
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('gzip (filtered-port `(,%gzip "-c") input))
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(else (error "unsupported compression scheme" compression))))
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(define (call-with-decompressed-port compression port proc)
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"Call PROC with a wrapper around PORT, a file port, that decompresses data
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read from PORT according to COMPRESSION, a symbol such as 'xz."
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(let-values (((decompressed pids)
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(decompressed-port compression port)))
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(dynamic-wind
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(const #f)
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(lambda ()
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(proc decompressed))
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(lambda ()
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(close-port decompressed)
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(unless (every (compose zero? cdr waitpid) pids)
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(error "decompressed-port failure" pids))))))
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(define (filtered-output-port command output)
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"Return an output port. Data written to that port is filtered through
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COMMAND and written to OUTPUT, an output file port. In addition, return a
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list of PIDs to wait for. OUTPUT must be unbuffered; otherwise, any buffered
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data is lost."
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(match (pipe)
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((in . out)
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(match (primitive-fork)
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(0
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(dynamic-wind
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(const #f)
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(lambda ()
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(close-port out)
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(close-port (current-input-port))
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(dup2 (fileno in) 0)
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(close-port (current-output-port))
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(dup2 (fileno output) 1)
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(catch 'system-error
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(lambda ()
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(apply execl (car command) command))
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(lambda args
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(format (current-error-port)
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"filtered-output-port: failed to execute '~{~a ~}': ~a~%"
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command (strerror (system-error-errno args))))))
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(lambda ()
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(primitive-_exit 1))))
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(child
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(close-port in)
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(values out (list child)))))))
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(define* (compressed-output-port compression output
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#:key (options '()))
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"Return an output port whose input is compressed according to COMPRESSION,
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a symbol such as 'xz, and then written to OUTPUT. In addition return a list
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of PIDs to wait for. OPTIONS is a list of strings passed to the compression
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program--e.g., '(\"--fast\")."
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(match compression
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((or #f 'none) (values output '()))
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('bzip2 (filtered-output-port `(,%bzip2 "-c" ,@options) output))
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('xz (filtered-output-port `(,%xz "-c" ,@options) output))
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('gzip (filtered-output-port `(,%gzip "-c" ,@options) output))
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(else (error "unsupported compression scheme" compression))))
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(define* (call-with-compressed-output-port compression port proc
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#:key (options '()))
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"Call PROC with a wrapper around PORT, a file port, that compresses data
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that goes to PORT according to COMPRESSION, a symbol such as 'xz. OPTIONS is
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a list of command-line arguments passed to the compression program."
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(let-values (((compressed pids)
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(compressed-output-port compression port
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#:options options)))
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(dynamic-wind
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(const #f)
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(lambda ()
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(proc compressed))
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(lambda ()
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(close-port compressed)
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(unless (every (compose zero? cdr waitpid) pids)
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(error "compressed-output-port failure" pids))))))
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;;;
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;;; Advisory file locking.
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;;;
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(define %struct-flock
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;; 'struct flock' from <fcntl.h>.
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(list short ; l_type
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short ; l_whence
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size_t ; l_start
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size_t ; l_len
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int)) ; l_pid
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(define F_SETLKW
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;; On Linux-based systems, this is usually 7, but not always
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;; (exceptions include SPARC.) On GNU/Hurd, it's 9.
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(compile-time-value
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(cond ((string-contains %host-type "sparc") 9) ; sparc-*-linux-gnu
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((string-contains %host-type "linux") 7) ; *-linux-gnu
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(else 9)))) ; *-gnu*
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(define F_SETLK
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;; Likewise: GNU/Hurd and SPARC use 8, while the others typically use 6.
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(compile-time-value
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(cond ((string-contains %host-type "sparc") 8) ; sparc-*-linux-gnu
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((string-contains %host-type "linux") 6) ; *-linux-gnu
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(else 8)))) ; *-gnu*
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(define F_xxLCK
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;; The F_RDLCK, F_WRLCK, and F_UNLCK constants.
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(compile-time-value
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(cond ((string-contains %host-type "sparc") #(1 2 3)) ; sparc-*-linux-gnu
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((string-contains %host-type "hppa") #(1 2 3)) ; hppa-*-linux-gnu
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((string-contains %host-type "linux") #(0 1 2)) ; *-linux-gnu
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(else #(1 2 3))))) ; *-gnu*
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(define fcntl-flock
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(let* ((ptr (dynamic-func "fcntl" (dynamic-link)))
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(proc (pointer->procedure int ptr `(,int ,int *))))
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(lambda* (fd-or-port operation #:key (wait? #t))
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"Perform locking OPERATION on the file beneath FD-OR-PORT. OPERATION
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must be a symbol, one of 'read-lock, 'write-lock, or 'unlock. When WAIT? is
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true, block until the lock is acquired; otherwise, thrown an 'flock-error'
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exception if it's already taken."
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(define (operation->int op)
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(case op
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((read-lock) (vector-ref F_xxLCK 0))
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((write-lock) (vector-ref F_xxLCK 1))
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((unlock) (vector-ref F_xxLCK 2))
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(else (error "invalid fcntl-flock operation" op))))
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(define fd
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(if (port? fd-or-port)
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(fileno fd-or-port)
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fd-or-port))
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;; XXX: 'fcntl' is a vararg function, but here we happily use the
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;; standard ABI; crossing fingers.
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(let ((err (proc fd
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(if wait?
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F_SETLKW ; lock & wait
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F_SETLK) ; non-blocking attempt
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(make-c-struct %struct-flock
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(list (operation->int operation)
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SEEK_SET
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0 0 ; whole file
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0)))))
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(or (zero? err)
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;; Presumably we got EAGAIN or so.
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(throw 'flock-error (errno)))))))
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;;;
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;;; Miscellaneous.
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;;;
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(define (memoize proc)
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"Return a memoizing version of PROC."
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(let ((cache (make-hash-table)))
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(lambda args
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(let ((results (hash-ref cache args)))
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(if results
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(apply values results)
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(let ((results (call-with-values (lambda ()
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(apply proc args))
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list)))
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(hash-set! cache args results)
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(apply values results)))))))
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(define (strip-keyword-arguments keywords args)
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"Remove all of the keyword arguments listed in KEYWORDS from ARGS."
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(let loop ((args args)
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(result '()))
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(match args
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(()
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(reverse result))
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(((? keyword? kw) arg . rest)
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(loop rest
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(if (memq kw keywords)
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result
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(cons* arg kw result))))
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((head . tail)
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(loop tail (cons head result))))))
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(define (default-keyword-arguments args defaults)
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"Return ARGS augmented with any keyword/value from DEFAULTS for
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keywords not already present in ARGS."
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(let loop ((defaults defaults)
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(args args))
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(match defaults
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((kw value rest ...)
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(loop rest
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(if (assoc-ref kw args)
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args
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(cons* kw value args))))
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(()
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args))))
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(define-syntax substitute-keyword-arguments
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(syntax-rules ()
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"Return a new list of arguments where the value for keyword arg KW is
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replaced by EXP. EXP is evaluated in a context where VAR is boud to the
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previous value of the keyword argument."
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((_ original-args ((kw var) exp) ...)
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(let loop ((args original-args)
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(before '()))
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(match args
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((kw var rest (... ...))
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(loop rest (cons* exp kw before)))
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...
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((x rest (... ...))
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(loop rest (cons x before)))
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(()
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(reverse before)))))))
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(define* (nix-system->gnu-triplet
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#:optional (system (%current-system)) (vendor "unknown"))
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"Return a guess of the GNU triplet corresponding to Nix system
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identifier SYSTEM."
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(match system
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("armhf-linux"
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(string-append "arm-" vendor "-linux-gnueabihf"))
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(_
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(let* ((dash (string-index system #\-))
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(arch (substring system 0 dash))
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(os (substring system (+ 1 dash))))
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(string-append arch
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"-" vendor "-"
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(if (string=? os "linux")
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"linux-gnu"
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os))))))
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(define (gnu-triplet->nix-system triplet)
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"Return the Nix system type corresponding to TRIPLET, a GNU triplet as
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returned by `config.guess'."
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(let ((triplet (cond ((string-match "^i[345]86-(.*)$" triplet)
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=>
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(lambda (m)
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(string-append "i686-" (match:substring m 1))))
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(else triplet))))
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(cond ((string-match "^arm[^-]*-([^-]+-)?linux-gnueabihf" triplet)
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"armhf-linux")
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((string-match "^([^-]+)-([^-]+-)?linux-gnu.*" triplet)
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=>
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(lambda (m)
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;; Nix omits `-gnu' for GNU/Linux.
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(string-append (match:substring m 1) "-linux")))
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((string-match "^([^-]+)-([^-]+-)?([[:alpha:]]+)([0-9]+\\.?)*$" triplet)
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=>
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(lambda (m)
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;; Nix strip the version number from names such as `gnu0.3',
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;; `darwin10.2.0', etc., and always strips the vendor part.
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(string-append (match:substring m 1) "-"
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(match:substring m 3))))
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(else triplet))))
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(define %current-system
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;; System type as expected by Nix, usually ARCHITECTURE-KERNEL.
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;; By default, this is equal to (gnu-triplet->nix-system %host-type).
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(make-parameter %system))
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(define %current-target-system
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;; Either #f or a GNU triplet representing the target system we are
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;; cross-building to.
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(make-parameter #f))
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(define version-compare
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(let ((strverscmp
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(let ((sym (or (dynamic-func "strverscmp" (dynamic-link))
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(error "could not find `strverscmp' (from GNU libc)"))))
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(pointer->procedure int sym (list '* '*)))))
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(lambda (a b)
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"Return '> when A denotes a newer version than B,
|
||
'< when A denotes a older version than B,
|
||
or '= when they denote equal versions."
|
||
(let ((result (strverscmp (string->pointer a) (string->pointer b))))
|
||
(cond ((positive? result) '>)
|
||
((negative? result) '<)
|
||
(else '=))))))
|
||
|
||
(define (version-prefix version-string num-parts)
|
||
"Truncate version-string to the first num-parts components of the version.
|
||
For example, (version-prefix \"2.1.47.4.23\" 3) returns \"2.1.47\""
|
||
(string-join (take (string-split version-string #\.) num-parts) "."))
|
||
|
||
|
||
(define (version-major+minor version-string)
|
||
"Return \"<major>.<minor>\", where major and minor are the major and
|
||
minor version numbers from version-string."
|
||
(version-prefix version-string 2))
|
||
|
||
(define (version>? a b)
|
||
"Return #t when A denotes a version strictly newer than B."
|
||
(eq? '> (version-compare a b)))
|
||
|
||
(define (version>=? a b)
|
||
"Return #t when A denotes a version newer or equal to B."
|
||
(case (version-compare a b)
|
||
((> =) #t)
|
||
(else #f)))
|
||
|
||
(define (guile-version>? str)
|
||
"Return #t if the running Guile version is greater than STR."
|
||
;; Note: Using (version>? (version) "2.0.5") or similar doesn't work,
|
||
;; because the result of (version) can have a prefix, like "2.0.5-deb1".
|
||
(version>? (string-append (major-version) "."
|
||
(minor-version) "."
|
||
(micro-version))
|
||
str))
|
||
|
||
(define (file-extension file)
|
||
"Return the extension of FILE or #f if there is none."
|
||
(let ((dot (string-rindex file #\.)))
|
||
(and dot (substring file (+ 1 dot) (string-length file)))))
|
||
|
||
(define (file-sans-extension file)
|
||
"Return the substring of FILE without its extension, if any."
|
||
(let ((dot (string-rindex file #\.)))
|
||
(if dot
|
||
(substring file 0 dot)
|
||
file)))
|
||
|
||
(define* (string-replace-substring str substr replacement
|
||
#:optional
|
||
(start 0)
|
||
(end (string-length str)))
|
||
"Replace all occurrences of SUBSTR in the START--END range of STR by
|
||
REPLACEMENT."
|
||
(match (string-length substr)
|
||
(0
|
||
(error "string-replace-substring: empty substring"))
|
||
(substr-length
|
||
(let loop ((start start)
|
||
(pieces (list (substring str 0 start))))
|
||
(match (string-contains str substr start end)
|
||
(#f
|
||
(string-concatenate-reverse
|
||
(cons (substring str start) pieces)))
|
||
(index
|
||
(loop (+ index substr-length)
|
||
(cons* replacement
|
||
(substring str start index)
|
||
pieces))))))))
|
||
|
||
(define (arguments-from-environment-variable variable)
|
||
"Retrieve value of environment variable denoted by string VARIABLE in the
|
||
form of a list of strings (`char-set:graphic' tokens) suitable for consumption
|
||
by `args-fold', if VARIABLE is defined, otherwise return an empty list."
|
||
(let ((env (getenv variable)))
|
||
(if env
|
||
(string-tokenize env char-set:graphic)
|
||
'())))
|
||
|
||
(define (call-with-temporary-output-file proc)
|
||
"Call PROC with a name of a temporary file and open output port to that
|
||
file; close the file and delete it when leaving the dynamic extent of this
|
||
call."
|
||
(let* ((directory (or (getenv "TMPDIR") "/tmp"))
|
||
(template (string-append directory "/guix-file.XXXXXX"))
|
||
(out (mkstemp! template)))
|
||
(dynamic-wind
|
||
(lambda ()
|
||
#t)
|
||
(lambda ()
|
||
(proc template out))
|
||
(lambda ()
|
||
(false-if-exception (close out))
|
||
(false-if-exception (delete-file template))))))
|
||
|
||
(define (call-with-temporary-directory proc)
|
||
"Call PROC with a name of a temporary directory; close the directory and
|
||
delete it when leaving the dynamic extent of this call."
|
||
(let* ((directory (or (getenv "TMPDIR") "/tmp"))
|
||
(template (string-append directory "/guix-directory.XXXXXX"))
|
||
(tmp-dir (mkdtemp! template)))
|
||
(dynamic-wind
|
||
(const #t)
|
||
(lambda ()
|
||
(proc tmp-dir))
|
||
(lambda ()
|
||
(false-if-exception (rmdir tmp-dir))))))
|
||
|
||
(define (with-atomic-file-output file proc)
|
||
"Call PROC with an output port for the file that is going to replace FILE.
|
||
Upon success, FILE is atomically replaced by what has been written to the
|
||
output port, and PROC's result is returned."
|
||
(let* ((template (string-append file ".XXXXXX"))
|
||
(out (mkstemp! template)))
|
||
(with-throw-handler #t
|
||
(lambda ()
|
||
(let ((result (proc out)))
|
||
(close out)
|
||
(rename-file template file)
|
||
result))
|
||
(lambda (key . args)
|
||
(false-if-exception (delete-file template))))))
|
||
|
||
(define fold2
|
||
(case-lambda
|
||
((proc seed1 seed2 lst)
|
||
"Like `fold', but with a single list and two seeds."
|
||
(let loop ((result1 seed1)
|
||
(result2 seed2)
|
||
(lst lst))
|
||
(if (null? lst)
|
||
(values result1 result2)
|
||
(call-with-values
|
||
(lambda () (proc (car lst) result1 result2))
|
||
(lambda (result1 result2)
|
||
(loop result1 result2 (cdr lst)))))))
|
||
((proc seed1 seed2 lst1 lst2)
|
||
"Like `fold', but with a two lists and two seeds."
|
||
(let loop ((result1 seed1)
|
||
(result2 seed2)
|
||
(lst1 lst1)
|
||
(lst2 lst2))
|
||
(if (or (null? lst1) (null? lst2))
|
||
(values result1 result2)
|
||
(call-with-values
|
||
(lambda () (proc (car lst1) (car lst2) result1 result2))
|
||
(lambda (result1 result2)
|
||
(fold2 proc result1 result2 (cdr lst1) (cdr lst2)))))))))
|
||
|
||
(define (fold-tree proc init children roots)
|
||
"Call (PROC NODE RESULT) for each node in the tree that is reachable from
|
||
ROOTS, using INIT as the initial value of RESULT. The order in which nodes
|
||
are traversed is not specified, however, each node is visited only once, based
|
||
on an eq? check. Children of a node to be visited are generated by
|
||
calling (CHILDREN NODE), the result of which should be a list of nodes that
|
||
are connected to NODE in the tree, or '() or #f if NODE is a leaf node."
|
||
(let loop ((result init)
|
||
(seen vlist-null)
|
||
(lst roots))
|
||
(match lst
|
||
(() result)
|
||
((head . tail)
|
||
(if (not (vhash-assq head seen))
|
||
(loop (proc head result)
|
||
(vhash-consq head #t seen)
|
||
(match (children head)
|
||
((or () #f) tail)
|
||
(children (append tail children))))
|
||
(loop result seen tail))))))
|
||
|
||
(define (fold-tree-leaves proc init children roots)
|
||
"Like fold-tree, but call (PROC NODE RESULT) only for leaf nodes."
|
||
(fold-tree
|
||
(lambda (node result)
|
||
(match (children node)
|
||
((or () #f) (proc node result))
|
||
(else result)))
|
||
init children roots))
|
||
|
||
|
||
;;;
|
||
;;; Source location.
|
||
;;;
|
||
|
||
;; A source location.
|
||
(define-record-type <location>
|
||
(make-location file line column)
|
||
location?
|
||
(file location-file) ; file name
|
||
(line location-line) ; 1-indexed line
|
||
(column location-column)) ; 0-indexed column
|
||
|
||
(define location
|
||
(memoize
|
||
(lambda (file line column)
|
||
"Return the <location> object for the given FILE, LINE, and COLUMN."
|
||
(and line column file
|
||
(make-location file line column)))))
|
||
|
||
(define (source-properties->location loc)
|
||
"Return a location object based on the info in LOC, an alist as returned
|
||
by Guile's `source-properties', `frame-source', `current-source-location',
|
||
etc."
|
||
(let ((file (assq-ref loc 'filename))
|
||
(line (assq-ref loc 'line))
|
||
(col (assq-ref loc 'column)))
|
||
;; In accordance with the GCS, start line and column numbers at 1. Note
|
||
;; that unlike LINE and `port-column', COL is actually 1-indexed here...
|
||
(location file (and line (+ line 1)) col)))
|