added wasm functionality

cmd/gcs/main.go

@@ -20,7 +20,8 @@ import (
 	"github.com/pkg/errors"
 	"github.com/sirupsen/logrus"
 	"go.opencensus.io/trace"
-
+
+	"github.com/Microsoft/hcsshim/global"
 	"github.com/Microsoft/hcsshim/internal/guest/bridge"
 	"github.com/Microsoft/hcsshim/internal/guest/kmsg"
 	"github.com/Microsoft/hcsshim/internal/guest/runtime/hcsv2"
@@ -195,6 +196,9 @@ func main() {
 	disableTimeSync := flag.Bool("disable-time-sync",
 		false,
 		"If true do not run chronyd time synchronization service inside the UVM")
+	crun := flag.Bool("crun",
+		false,
+		"setting global runtime")
 	scrubLogs := flag.Bool("scrub-logs", false, "If true, scrub potentially sensitive information from logging")
 	initialPolicyStance := flag.String("initial-policy-stance",
 		"allow",
@@ -294,6 +298,11 @@ func main() {
 	// Continuously log /dev/kmsg
 	go kmsg.ReadForever(kmsg.LogLevel(*kmsgLogLevel))
 
+
+	if *crun {
+		global.SetGlobalRuntime("crun")
+	}
+
 	tport := &transport.VsockTransport{}
 	rtime, err := runc.NewRuntime(baseLogPath)
 	if err != nil {

global/global.go

@@ -0,0 +1,14 @@
+// config/config.go
+package global
+
+var global_runtime string
+
+// Setter function
+func SetGlobalRuntime(value string) {
+    global_runtime = value
+}
+
+// Getter function
+func GetGlobalRuntime() string {
+    return global_runtime
+}

internal/guest/runtime/runc/utils.go

@@ -15,6 +15,7 @@ import (
 	"github.com/pkg/errors"
 	"github.com/sirupsen/logrus"
 
+	"github.com/Microsoft/hcsshim/global"
 	"github.com/Microsoft/hcsshim/internal/guest/runtime"
 )
 
@@ -171,5 +172,8 @@ func runcCommandLog(logPath string, args ...string) *exec.Cmd {
 }
 
 func runcCommand(args ...string) *exec.Cmd {
+	if global.GetGlobalRuntime() == "crun" {
+		return exec.Command("crun", args...)
+	}
 	return exec.Command("runc", args...)
 }

internal/oci/uvm.go

@@ -308,6 +308,7 @@ func SpecToUVMCreateOpts(ctx context.Context, s *specs.Spec, id, owner string) (
 		handleAnnotationBootFilesPath(ctx, s.Annotations, lopts)
 		lopts.EnableScratchEncryption = ParseAnnotationsBool(ctx, s.Annotations, annotations.EncryptedScratchDisk, lopts.EnableScratchEncryption)
 		lopts.SecurityPolicy = ParseAnnotationsString(s.Annotations, annotations.SecurityPolicy, lopts.SecurityPolicy)
+		lopts.Runtime = ParseAnnotationsString(s.Annotations, annotations.Runtime, lopts.Runtime)
 		lopts.SecurityPolicyEnforcer = ParseAnnotationsString(s.Annotations, annotations.SecurityPolicyEnforcer, lopts.SecurityPolicyEnforcer)
 		lopts.UVMReferenceInfoFile = ParseAnnotationsString(s.Annotations, annotations.UVMReferenceInfoFile, lopts.UVMReferenceInfoFile)
 		lopts.KernelBootOptions = ParseAnnotationsString(s.Annotations, annotations.KernelBootOptions, lopts.KernelBootOptions)

internal/uvm/create_lcow.go

@@ -133,6 +133,7 @@ type OptionsLCOW struct {
 	HclEnabled              *bool                // Whether to enable the host compatibility layer
 	ExtraVSockPorts         []uint32             // Extra vsock ports to allow
 	AssignedDevices         []VPCIDeviceID       // AssignedDevices are devices to add on pod boot
+	Runtime                 string               // runtime
 }
 
 // defaultLCOWOSBootFilesPath returns the default path used to locate the LCOW
@@ -182,6 +183,7 @@ func NewDefaultOptionsLCOW(id, owner string) *OptionsLCOW {
 			SecurityPolicyEnabled: false,
 			UVMReferenceInfoFile:  UVMReferenceInfoFile,
 		},
+		Runtime: "",
 	}
 
 	opts.UpdateBootFilesPath(context.TODO(), defaultLCOWOSBootFilesPath())
@@ -835,6 +837,10 @@ func makeLCOWDoc(ctx context.Context, opts *OptionsLCOW, uvm *UtilityVM) (_ *hcs
 		kernelArgs += " " + opts.KernelBootOptions
 	}
 
+	if opts.Runtime == "runhcs-lcow-crun" {
+		opts.ExecCommandLine = fmt.Sprintf("%s -crun", opts.ExecCommandLine)
+	}
+
 	if !opts.VPCIEnabled {
 		kernelArgs += ` pci=off`
 	}

pkg/annotations/annotations.go

@@ -181,6 +181,9 @@ const (
 	// VPMemNoMultiMapping indicates that we should disable LCOW vpmem layer multi mapping.
 	VPMemNoMultiMapping = "io.microsoft.virtualmachine.lcow.vpmem.nomultimapping"
 
+    // runtime is used to specify low-level runtime option.
+	Runtime = "runtime"
+
 	// KernelBootOptions is used to specify kernel options used while booting a linux kernel.
 	KernelBootOptions = "io.microsoft.virtualmachine.lcow.kernelbootoptions"