diff options
| -rw-r--r-- | guix/zlib.scm | 46 |
1 files changed, 16 insertions, 30 deletions
diff --git a/guix/zlib.scm b/guix/zlib.scm index 955589ab48..3bd0ad86c9 100644 --- a/guix/zlib.scm +++ b/guix/zlib.scm @@ -1,5 +1,5 @@ ;;; GNU Guix --- Functional package management for GNU -;;; Copyright © 2016 Ludovic Courtès <ludo@gnu.org> +;;; Copyright © 2016, 2017 Ludovic Courtès <ludo@gnu.org> ;;; ;;; This file is part of GNU Guix. ;;; @@ -149,31 +149,6 @@ the number of uncompressed bytes written, a strictly positive integer." ;; Z_DEFAULT_COMPRESSION. -1) -(define (close-procedure gzfile port) - "Return a procedure that closes GZFILE, ensuring its underlying PORT is -closed even if closing GZFILE triggers an exception." - (let-syntax ((ignore-EBADF - (syntax-rules () - ((_ exp) - (catch 'system-error - (lambda () - exp) - (lambda args - (unless (= EBADF (system-error-errno args)) - (apply throw args)))))))) - - (lambda () - (catch 'zlib-error - (lambda () - ;; 'gzclose' closes the underlying file descriptor. 'close-port' - ;; calls close(2) and gets EBADF, which we swallow. - (gzclose gzfile) - (ignore-EBADF (close-port port))) - (lambda args - ;; Make sure PORT is closed despite the zlib error. - (ignore-EBADF (close-port port)) - (apply throw args)))))) - (define* (make-gzip-input-port port #:key (buffer-size %default-buffer-size)) "Return an input port that decompresses data read from PORT, a file port. PORT is automatically closed when the resulting port is closed. BUFFER-SIZE @@ -183,7 +158,14 @@ buffered input, which would be lost (and is lost anyway)." (define gzfile (match (drain-input port) ("" ;PORT's buffer is empty - (gzdopen (fileno port) "r")) + ;; 'gzclose' will eventually close the file descriptor beneath PORT. + ;; 'close-port' on PORT would get EBADF if 'gzclose' already closed it, + ;; so that's no good; revealed ports are no good either because they + ;; leak (see <https://bugs.gnu.org/28784>); calling 'close-port' after + ;; 'gzclose' doesn't work either because it leads to a race condition + ;; (see <https://bugs.gnu.org/29335>). So we dup and close PORT right + ;; away. + (gzdopen (dup (fileno port)) "r")) (_ ;; This is unrecoverable but it's better than having the buffered input ;; be lost, leading to unclear end-of-file or corrupt-data errors down @@ -197,8 +179,10 @@ buffered input, which would be lost (and is lost anyway)." (unless (= buffer-size %default-buffer-size) (gzbuffer! gzfile buffer-size)) + (close-port port) ;we no longer need it (make-custom-binary-input-port "gzip-input" read! #f #f - (close-procedure gzfile port))) + (lambda () + (gzclose gzfile)))) (define* (make-gzip-output-port port #:key @@ -210,7 +194,7 @@ port is closed." (define gzfile (begin (force-output port) ;empty PORT's buffer - (gzdopen (fileno port) + (gzdopen (dup (fileno port)) (string-append "w" (number->string level))))) (define (write! bv start count) @@ -219,8 +203,10 @@ port is closed." (unless (= buffer-size %default-buffer-size) (gzbuffer! gzfile buffer-size)) + (close-port port) (make-custom-binary-output-port "gzip-output" write! #f #f - (close-procedure gzfile port))) + (lambda () + (gzclose gzfile)))) (define* (call-with-gzip-input-port port proc #:key (buffer-size %default-buffer-size)) |