filecache: use rename for an atomic write #1816
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valpackett
requested review from
codefromthecrypt,
mathetake and
evacchi
as code owners
ncruces
approved these changes
Oct 24, 2023
internal/filecache/file_cache.go
Outdated
| @@ -69,12 +69,28 @@ func (fc *fileCache) Add(key Key, content io.Reader) (err error) { | |||
| fc.mux.Lock() | |||
| defer fc.mux.Unlock() | |||
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| file, err := os.Create(fc.path(key)) | |||
| // Use rename for an atomic write (on Unix, at least; Windows needs special direct syscall code) | |||
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Since https://go.dev/cl/6140 I'd say os.Rename is "atomic enough" on Windows (using MoveFileEx), so I don't think we really need this comment.
This prevents e.g. getting killed during writing from leaving incomplete/corrupt data in the cache directory. Signed-off-by: Val Packett <val@packett.cool>
mathetake
approved these changes
Oct 25, 2023
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This prevents e.g. getting killed during writing from leaving incomplete/corrupt data in the cache directory.