diff options
Diffstat (limited to 'gnu/services.scm')
| -rw-r--r-- | gnu/services.scm | 32 |
1 files changed, 32 insertions, 0 deletions
diff --git a/gnu/services.scm b/gnu/services.scm index f6dc56d940..6509a9014e 100644 --- a/gnu/services.scm +++ b/gnu/services.scm @@ -89,6 +89,7 @@ system-service-type provenance-service-type + system-provenance boot-service-type cleanup-service-type activation-service-type @@ -423,6 +424,19 @@ be parsed by tools; it's potentially more future-proof than code." (branch ,(channel-branch channel)) (commit ,(channel-commit channel)))) +(define (sexp->channel sexp) + "Return the channel corresponding to SEXP, an sexp as found in the +\"provenance\" file produced by 'provenance-service-type'." + (match sexp + (('channel ('name name) + ('url url) + ('branch branch) + ('commit commit) + rest ...) + ;; XXX: In the future REST may include a channel introduction. + (channel (name name) (url url) + (branch branch) (commit commit))))) + (define (provenance-file channels config-file) "Return a 'provenance' file describing CHANNELS, a list of channels, and CONFIG-FILE, which can be either #f or a <local-file> containing the OS @@ -474,6 +488,24 @@ channels in use and CONFIG-FILE, if it is true." itself: the channels used when building the system, and its configuration file, when available."))) +(define (system-provenance system) + "Given SYSTEM, the file name of a system generation, return two values: the +list of channels SYSTEM is built from, and its configuration file. If that +information is missing, return the empty list (for channels) and possibly +#false (for the configuration file)." + (catch 'system-error + (lambda () + (match (call-with-input-file (string-append system "/provenance") + read) + (('provenance ('version 0) + ('channels channels ...) + ('configuration-file config-file)) + (values (map sexp->channel channels) + config-file)) + (_ + (values '() #f)))) + (lambda _ + (values '() #f)))) ;;; ;;; Cleanup. |