diff options
Diffstat (limited to 'pkg/sentry/kernel/semaphore')
| -rwxr-xr-x | pkg/sentry/kernel/semaphore/waiter_list.go | 13 |
1 files changed, 10 insertions, 3 deletions
diff --git a/pkg/sentry/kernel/semaphore/waiter_list.go b/pkg/sentry/kernel/semaphore/waiter_list.go index 27120afe3..4bfe5ff95 100755 --- a/pkg/sentry/kernel/semaphore/waiter_list.go +++ b/pkg/sentry/kernel/semaphore/waiter_list.go @@ -52,12 +52,21 @@ func (l *waiterList) Back() *waiter { return l.tail } +// Len returns the number of elements in the list. +// +// NOTE: This is an O(n) operation. +func (l *waiterList) Len() (count int) { + for e := l.Front(); e != nil; e = e.Next() { + count++ + } + return count +} + // PushFront inserts the element e at the front of list l. func (l *waiterList) PushFront(e *waiter) { linker := waiterElementMapper{}.linkerFor(e) linker.SetNext(l.head) linker.SetPrev(nil) - if l.head != nil { waiterElementMapper{}.linkerFor(l.head).SetPrev(e) } else { @@ -72,7 +81,6 @@ func (l *waiterList) PushBack(e *waiter) { linker := waiterElementMapper{}.linkerFor(e) linker.SetNext(nil) linker.SetPrev(l.tail) - if l.tail != nil { waiterElementMapper{}.linkerFor(l.tail).SetNext(e) } else { @@ -93,7 +101,6 @@ func (l *waiterList) PushBackList(m *waiterList) { l.tail = m.tail } - m.head = nil m.tail = nil } |