1
0
mirror of https://github.com/v2fly/v2ray-core.git synced 2024-12-22 18:17:52 -05:00
v2fly/common/task/task.go
2018-12-06 11:35:02 +01:00

53 lines
874 B
Go

package task
import (
"context"
"v2ray.com/core/common/signal/semaphore"
)
// OnSuccess executes g() after f() returns nil.
func OnSuccess(f func() error, g func() error) func() error {
return func() error {
if err := f(); err != nil {
return err
}
return g()
}
}
// Run executes a list of tasks in parallel, returns the first error encountered or nil if all tasks pass.
func Run(ctx context.Context, tasks ...func() error) error {
n := len(tasks)
s := semaphore.New(n)
done := make(chan error, 1)
for _, task := range tasks {
<-s.Wait()
go func(f func() error) {
err := f()
if err == nil {
s.Signal()
return
}
select {
case done <- err:
default:
}
}(task)
}
for i := 0; i < n; i++ {
select {
case err := <-done:
return err
case <-ctx.Done():
return ctx.Err()
case <-s.Wait():
}
}
return nil
}