diff options
| -rw-r--r-- | stm.go | 42 |
1 files changed, 22 insertions, 20 deletions
@@ -86,7 +86,8 @@ import ( // transaction should be retried. const Retry = "retry" -// The globalLock serializes transaction verification/committal. +// The globalLock serializes transaction verification/committal. globalCond is +// used to signal that at least one Var has changed. var globalLock sync.Mutex var globalCond = sync.NewCond(&globalLock) @@ -182,25 +183,6 @@ func catchRetry(fn func(*Tx), tx *Tx) (retry bool) { return } -// Select runs the supplied functions in order. Execution stops when a -// function succeeds without calling Retry. If no functions succeed, the -// entire selection will be retried. -func Select(fns ...func(*Tx)) func(*Tx) { - return func(tx *Tx) { - switch len(fns) { - case 0: - // empty Select blocks forever - tx.Retry() - case 1: - fns[0](tx) - default: - if catchRetry(fns[0], tx) { - Select(fns[1:]...)(tx) - } - } - } -} - // Atomically executes the atomic function fn. func Atomically(fn func(*Tx)) { retry: @@ -210,6 +192,7 @@ retry: writes: make(map[*Var]interface{}), } if catchRetry(fn, tx) { + // wait for one of the variables we read to change before retrying tx.wait() goto retry } @@ -254,3 +237,22 @@ func Compose(fns ...func(*Tx)) func(*Tx) { } } } + +// Select runs the supplied functions in order. Execution stops when a +// function succeeds without calling Retry. If no functions succeed, the +// entire selection will be retried. +func Select(fns ...func(*Tx)) func(*Tx) { + return func(tx *Tx) { + switch len(fns) { + case 0: + // empty Select blocks forever + tx.Retry() + case 1: + fns[0](tx) + default: + if catchRetry(fns[0], tx) { + Select(fns[1:]...)(tx) + } + } + } +} |