diff options
Diffstat (limited to 'guix/ui.scm')
| -rw-r--r-- | guix/ui.scm | 33 |
1 files changed, 33 insertions, 0 deletions
diff --git a/guix/ui.scm b/guix/ui.scm index dcad55e72e..944c9f87fa 100644 --- a/guix/ui.scm +++ b/guix/ui.scm @@ -43,6 +43,7 @@ show-version-and-exit show-bug-report-information string->number* + size->number show-what-to-build call-with-error-handling with-error-handling @@ -160,6 +161,38 @@ General help using GNU software: <http://www.gnu.org/gethelp/>")) (or (string->number str) (leave (_ "~a: invalid number~%") str))) +(define (size->number str) + "Convert STR, a storage measurement representation such as \"1024\" or +\"1MiB\", to a number of bytes. Raise an error if STR could not be +interpreted." + (define unit-pos + (string-rindex str char-set:digit)) + + (define unit + (and unit-pos (substring str (+ 1 unit-pos)))) + + (let* ((numstr (if unit-pos + (substring str 0 (+ 1 unit-pos)) + str)) + (num (string->number numstr))) + (unless num + (leave (_ "invalid number: ~a~%") numstr)) + + ((compose inexact->exact round) + (* num + (match unit + ("KiB" (expt 2 10)) + ("MiB" (expt 2 20)) + ("GiB" (expt 2 30)) + ("TiB" (expt 2 40)) + ("KB" (expt 10 3)) + ("MB" (expt 10 6)) + ("GB" (expt 10 9)) + ("TB" (expt 10 12)) + ("" 1) + (_ + (leave (_ "unknown unit: ~a~%") unit))))))) + (define (call-with-error-handling thunk) "Call THUNK within a user-friendly error handler." (guard (c ((package-input-error? c) |