diff options
Diffstat (limited to 'guix/store/deduplication.scm')
| -rw-r--r-- | guix/store/deduplication.scm | 39 |
1 files changed, 19 insertions, 20 deletions
diff --git a/guix/store/deduplication.scm b/guix/store/deduplication.scm index d3139eb904..6ff4a50de5 100644 --- a/guix/store/deduplication.scm +++ b/guix/store/deduplication.scm @@ -88,28 +88,27 @@ LINK-PREFIX." (lambda args (if (= (system-error-errno args) EEXIST) (try (tempname-in link-prefix)) - (throw 'system-error args)))))) + (apply throw args)))))) ;; There are 3 main kinds of errors we can get from hardlinking: "Too many ;; things link to this" (EMLINK), "this link already exists" (EEXIST), and ;; "can't fit more stuff in this directory" (ENOSPC). -(define (replace-with-link target to-replace) - "Atomically replace the file TO-REPLACE with a link to TARGET. Note: TARGET -and TO-REPLACE must be on the same file system." - (let ((temp-link (get-temp-link target (dirname to-replace)))) - (rename-file temp-link to-replace))) +(define* (replace-with-link target to-replace + #:key (swap-directory (dirname target))) + "Atomically replace the file TO-REPLACE with a link to TARGET. Use +SWAP-DIRECTORY as the directory to store temporary hard links. -(define-syntax-rule (false-if-system-error (errors ...) exp ...) - "Given ERRORS, a list of system error codes to ignore, evaluates EXP... and -return #f if any of the system error codes in the given list are thrown." - (catch 'system-error - (lambda () - exp ...) - (lambda args - (if (member (system-error-errno args) (list errors ...)) - #f - (apply throw args))))) +Note: TARGET, TO-REPLACE, and SWAP-DIRECTORY must be on the same file system." + (let ((temp-link (get-temp-link target swap-directory))) + (make-file-writable (dirname to-replace)) + (catch 'system-error + (lambda () + (rename-file temp-link to-replace)) + (lambda args + (delete-file temp-link) + (unless (= EMLINK (system-error-errno args)) + (apply throw args)))))) (define* (deduplicate path hash #:key (store %store-directory)) "Check if a store item with sha256 hash HASH already exists. If so, @@ -131,8 +130,8 @@ under STORE." #:store store)))) (scandir path)) (if (file-exists? link-file) - (false-if-system-error (EMLINK) - (replace-with-link link-file path)) + (replace-with-link link-file path + #:swap-directory links-directory) (catch 'system-error (lambda () (link path link-file)) @@ -141,8 +140,8 @@ under STORE." (cond ((= errno EEXIST) ;; Someone else put an entry for PATH in ;; LINKS-DIRECTORY before we could. Let's use it. - (false-if-system-error (EMLINK) - (replace-with-link path link-file))) + (replace-with-link path link-file + #:swap-directory links-directory)) ((= errno ENOSPC) ;; There's not enough room in the directory index for ;; more entries in .links, but that's fine: we can |