diff options
Diffstat (limited to 'vendor/codeberg.org/gruf/go-errors/once.go')
-rw-r--r-- | vendor/codeberg.org/gruf/go-errors/once.go | 45 |
1 files changed, 45 insertions, 0 deletions
diff --git a/vendor/codeberg.org/gruf/go-errors/once.go b/vendor/codeberg.org/gruf/go-errors/once.go new file mode 100644 index 000000000..ba21ed695 --- /dev/null +++ b/vendor/codeberg.org/gruf/go-errors/once.go @@ -0,0 +1,45 @@ +package errors + +import ( + "sync/atomic" + "unsafe" +) + +// OnceError is an error structure that supports safe multi-threaded +// usage and setting only once (until reset) +type OnceError struct { + err unsafe.Pointer +} + +// NewOnce returns a new OnceError instance +func NewOnce() OnceError { + return OnceError{ + err: nil, + } +} + +func (e *OnceError) Store(err error) { + // Nothing to do + if err == nil { + return + } + + // Only set if not already + atomic.CompareAndSwapPointer( + &e.err, + nil, + unsafe.Pointer(&err), + ) +} + +func (e *OnceError) Load() error { + return *(*error)(atomic.LoadPointer(&e.err)) +} + +func (e *OnceError) IsSet() bool { + return (atomic.LoadPointer(&e.err) != nil) +} + +func (e *OnceError) Reset() { + atomic.StorePointer(&e.err, nil) +} |