diff options
Diffstat (limited to 'internal/persistence/atomic.go')
| -rw-r--r-- | internal/persistence/atomic.go | 12 |
1 files changed, 10 insertions, 2 deletions
diff --git a/internal/persistence/atomic.go b/internal/persistence/atomic.go index a3cc06a..2b24391 100644 --- a/internal/persistence/atomic.go +++ b/internal/persistence/atomic.go @@ -3,11 +3,19 @@ package persistence import ( + "errors" "fmt" "os" "path/filepath" ) +// ErrDurabilityUncertain reports that the atomic replacement was renamed into +// place but the directory could not be synced (or a post-rename chmod +// failed). The new content is visible to readers, but a crash may still lose +// it. Callers that must distinguish "nothing happened" from "the replacement +// landed but may not survive a crash" should test errors.Is against this. +var ErrDurabilityUncertain = errors.New("replacement completed; durability uncertain") + // WriteFile writes and syncs a temporary file in the destination directory, // atomically renames it over path, then syncs the directory. Existing file // permissions are preserved; perm is used for new files. Callers must own the @@ -43,11 +51,11 @@ func WriteFile(path string, data []byte, perm os.FileMode) error { } d, err := os.Open(dir) if err != nil { - return fmt.Errorf("replacement completed; open directory for sync: %w", err) + return fmt.Errorf("%w: open directory for sync: %v", ErrDurabilityUncertain, err) } defer d.Close() if err := d.Sync(); err != nil { - return fmt.Errorf("replacement completed; sync directory: %w", err) + return fmt.Errorf("%w: sync directory: %v", ErrDurabilityUncertain, err) } return nil } |