union: Gracefully handle dangling symlinks in the input.

Fixes <http://bugs.gnu.org/26949>.
Reported by Pjotr Prins <pjotr.public12@thebird.nl>.

* guix/build/union.scm (file-is-directory?): Return #f when FILE does
not exist or is a dangling symlink.
(file=?): Pass #f as a second argument to 'stat'; return #f when both
ST1 or ST2 is #f.
* tests/profiles.scm (test-equalm): New macro.
("union vs. dangling symlink"): New test.
This commit is contained in:
Ludovic Courtès 2017-05-18 11:35:45 +02:00
parent 41f76ae08a
commit 22ef06b801
No known key found for this signature in database
GPG key ID: 090B11993D9AEBB5
3 changed files with 53 additions and 20 deletions

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@ -17,6 +17,7 @@
(eval . (put 'call-with-prompt 'scheme-indent-function 1)) (eval . (put 'call-with-prompt 'scheme-indent-function 1))
(eval . (put 'test-assert 'scheme-indent-function 1)) (eval . (put 'test-assert 'scheme-indent-function 1))
(eval . (put 'test-assertm 'scheme-indent-function 1)) (eval . (put 'test-assertm 'scheme-indent-function 1))
(eval . (put 'test-equalm 'scheme-indent-function 1))
(eval . (put 'test-equal 'scheme-indent-function 1)) (eval . (put 'test-equal 'scheme-indent-function 1))
(eval . (put 'test-eq 'scheme-indent-function 1)) (eval . (put 'test-eq 'scheme-indent-function 1))
(eval . (put 'call-with-input-string 'scheme-indent-function 1)) (eval . (put 'call-with-input-string 'scheme-indent-function 1))

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@ -47,31 +47,34 @@ (define (files-in-directory dirname)
(loop (cons file files))))))) (loop (cons file files)))))))
(define (file-is-directory? file) (define (file-is-directory? file)
(eq? 'directory (stat:type (stat file)))) (match (stat file #f)
(#f #f) ;maybe a dangling symlink
(st (eq? 'directory (stat:type st)))))
(define (file=? file1 file2) (define (file=? file1 file2)
"Return #t if FILE1 and FILE2 are regular files and their contents are "Return #t if FILE1 and FILE2 are regular files and their contents are
identical, #f otherwise." identical, #f otherwise."
(let ((st1 (stat file1)) (let ((st1 (stat file1 #f))
(st2 (stat file2))) (st2 (stat file2 #f)))
;; When deduplication is enabled, identical files share the same inode. ;; When deduplication is enabled, identical files share the same inode.
(or (= (stat:ino st1) (stat:ino st2)) (and st1 st2
(and (eq? (stat:type st1) 'regular) (or (= (stat:ino st1) (stat:ino st2))
(eq? (stat:type st2) 'regular) (and (eq? (stat:type st1) 'regular)
(= (stat:size st1) (stat:size st2)) (eq? (stat:type st2) 'regular)
(call-with-input-file file1 (= (stat:size st1) (stat:size st2))
(lambda (port1) (call-with-input-file file1
(call-with-input-file file2 (lambda (port1)
(lambda (port2) (call-with-input-file file2
(define len 8192) (lambda (port2)
(define buf1 (make-bytevector len)) (define len 8192)
(define buf2 (make-bytevector len)) (define buf1 (make-bytevector len))
(let loop () (define buf2 (make-bytevector len))
(let ((n1 (get-bytevector-n! port1 buf1 0 len)) (let loop ()
(n2 (get-bytevector-n! port2 buf2 0 len))) (let ((n1 (get-bytevector-n! port1 buf1 0 len))
(and (equal? n1 n2) (n2 (get-bytevector-n! port2 buf2 0 len)))
(or (eof-object? n1) (and (equal? n1 n2)
(loop))))))))))))) (or (eof-object? n1)
(loop))))))))))))))
(define* (union-build output inputs (define* (union-build output inputs
#:key (log-port (current-error-port)) #:key (log-port (current-error-port))

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@ -50,6 +50,12 @@ (define-syntax-rule (test-assertm name exp)
(run-with-store %store exp (run-with-store %store exp
#:guile-for-build (%guile-for-build)))) #:guile-for-build (%guile-for-build))))
(define-syntax-rule (test-equalm name value exp)
(test-equal name
value
(run-with-store %store exp
#:guile-for-build (%guile-for-build))))
;; Example manifest entries. ;; Example manifest entries.
(define guile-1.8.8 (define guile-1.8.8
@ -366,6 +372,29 @@ (define (find-input name)
get-string-all) get-string-all)
"foo!")))))) "foo!"))))))
(test-equalm "union vs. dangling symlink" ;<https://bugs.gnu.org/26949>
"does-not-exist"
(mlet* %store-monad
((thing1 -> (dummy-package "dummy"
(build-system trivial-build-system)
(arguments
`(#:guile ,%bootstrap-guile
#:builder
(let ((out (assoc-ref %outputs "out")))
(mkdir out)
(symlink "does-not-exist"
(string-append out "/dangling"))
#t)))))
(thing2 -> (package (inherit thing1) (name "dummy2")))
(drv (profile-derivation (packages->manifest
(list thing1 thing2))
#:hooks '()
#:locales? #f))
(profile -> (derivation->output-path drv)))
(mbegin %store-monad
(built-derivations (list drv))
(return (readlink (readlink (string-append profile "/dangling")))))))
(test-end "profiles") (test-end "profiles")
;;; Local Variables: ;;; Local Variables: