seba-365 - implemented dep
Change-Id: Ia6226d50e7615935a0c8876809a687427ff88c22
diff --git a/vendor/github.com/mongodb/mongo-go-driver/internal/semaphore.go b/vendor/github.com/mongodb/mongo-go-driver/internal/semaphore.go
new file mode 100644
index 0000000..792e531
--- /dev/null
+++ b/vendor/github.com/mongodb/mongo-go-driver/internal/semaphore.go
@@ -0,0 +1,57 @@
+// Copyright (C) MongoDB, Inc. 2017-present.
+//
+// Licensed under the Apache License, Version 2.0 (the "License"); you may
+// not use this file except in compliance with the License. You may obtain
+// a copy of the License at http://www.apache.org/licenses/LICENSE-2.0
+
+package internal
+
+import (
+ "context"
+ "errors"
+)
+
+// NewSemaphore creates a new semaphore.
+func NewSemaphore(slots uint64) *Semaphore {
+ ch := make(chan struct{}, slots)
+ for i := uint64(0); i < slots; i++ {
+ ch <- struct{}{}
+ }
+
+ return &Semaphore{
+ permits: ch,
+ }
+}
+
+// Semaphore is a synchronization primitive that controls access
+// to a common resource.
+type Semaphore struct {
+ permits chan struct{}
+}
+
+// Len gets the number of permits available.
+func (s *Semaphore) Len() uint64 {
+ return uint64(len(s.permits))
+}
+
+// Wait waits until a resource is available or until the context
+// is done.
+func (s *Semaphore) Wait(ctx context.Context) error {
+ select {
+ case <-s.permits:
+ return nil
+ case <-ctx.Done():
+ return ctx.Err()
+ }
+}
+
+// Release releases a resource back into the pool.
+func (s *Semaphore) Release() error {
+ select {
+ case s.permits <- struct{}{}:
+ default:
+ return errors.New("internal.Semaphore.Release: attempt to release more resources than are available")
+ }
+
+ return nil
+}