Add Event controls

Add Event controls and implement "stream" commands.

PiperOrigin-RevId: 390691702

2 files changed, 35 insertions, 0 deletions

diff --git a/runsc/sandbox/BUILD b/runsc/sandbox/BUILD
index bc4a3fa32..d625230dd 100644
--- a/runsc/sandbox/BUILD
+++ b/runsc/sandbox/BUILD
@@ -17,12 +17,14 @@ go_library(
         "//pkg/control/client",
         "//pkg/control/server",
         "//pkg/coverage",
+        "//pkg/eventchannel",
         "//pkg/log",
         "//pkg/sentry/control",
         "//pkg/sentry/platform",
         "//pkg/sync",
         "//pkg/tcpip/header",
         "//pkg/tcpip/stack",
+        "//pkg/unet",
         "//pkg/urpc",
         "//runsc/boot",
         "//runsc/boot/platforms",
diff --git a/runsc/sandbox/sandbox.go b/runsc/sandbox/sandbox.go
index c8c6886c7..9fbce6bd6 100644
--- a/runsc/sandbox/sandbox.go
+++ b/runsc/sandbox/sandbox.go
@@ -35,10 +35,12 @@ import (
 	"gvisor.dev/gvisor/pkg/control/client"
 	"gvisor.dev/gvisor/pkg/control/server"
 	"gvisor.dev/gvisor/pkg/coverage"
+	"gvisor.dev/gvisor/pkg/eventchannel"
 	"gvisor.dev/gvisor/pkg/log"
 	"gvisor.dev/gvisor/pkg/sentry/control"
 	"gvisor.dev/gvisor/pkg/sentry/platform"
 	"gvisor.dev/gvisor/pkg/sync"
+	"gvisor.dev/gvisor/pkg/unet"
 	"gvisor.dev/gvisor/pkg/urpc"
 	"gvisor.dev/gvisor/runsc/boot"
 	"gvisor.dev/gvisor/runsc/boot/platforms"
@@ -1073,6 +1075,37 @@ func (s *Sandbox) Reduce(cid string, wait bool) error {
 	}, nil)
 }
 
+// Stream sends the AttachDebugEmitter call for a container in the sandbox, and
+// dumps filtered events to out.
+func (s *Sandbox) Stream(cid string, filters []string, out *os.File) error {
+	log.Debugf("Stream sandbox %q", s.ID)
+	conn, err := s.sandboxConnect()
+	if err != nil {
+		return err
+	}
+	defer conn.Close()
+
+	r, w, err := unet.SocketPair(false)
+	if err != nil {
+		return err
+	}
+
+	wfd, err := w.Release()
+	if err != nil {
+		return fmt.Errorf("failed to release write socket FD: %v", err)
+	}
+
+	if err := conn.Call(boot.EventsAttachDebugEmitter, &control.EventsOpts{
+		FilePayload: urpc.FilePayload{Files: []*os.File{
+			os.NewFile(uintptr(wfd), "event sink"),
+		}},
+	}, nil); err != nil {
+		return fmt.Errorf("AttachDebugEmitter failed: %v", err)
+	}
+
+	return eventchannel.ProcessAll(r, filters, out)
+}
+
 // IsRunning returns true if the sandbox or gofer process is running.
 func (s *Sandbox) IsRunning() bool {
 	if s.Pid != 0 {