Merge pull request #1 from google/master

catch up

1 files changed, 14 insertions, 1 deletions

diff --git a/pkg/sentry/kernel/tty.go b/pkg/sentry/kernel/tty.go
index 34f84487a..d0e0810e8 100644
--- a/pkg/sentry/kernel/tty.go
+++ b/pkg/sentry/kernel/tty.go
@@ -14,15 +14,28 @@
 
 package kernel
 
-import "sync"
+import "gvisor.dev/gvisor/pkg/sync"
 
 // TTY defines the relationship between a thread group and its controlling
 // terminal.
 //
 // +stateify savable
 type TTY struct {
+	// Index is the terminal index. It is immutable.
+	Index uint32
+
 	mu sync.Mutex `state:"nosave"`
 
 	// tg is protected by mu.
 	tg *ThreadGroup
 }
+
+// TTY returns the thread group's controlling terminal. If nil, there is no
+// controlling terminal.
+func (tg *ThreadGroup) TTY() *TTY {
+	tg.pidns.owner.mu.RLock()
+	defer tg.pidns.owner.mu.RUnlock()
+	tg.signalHandlers.mu.Lock()
+	defer tg.signalHandlers.mu.Unlock()
+	return tg.tty
+}