avoid close 'nil' panics if any (#18890)

brings a generic implementation that
prints a stack trace for 'nil' channel
closes(), if not safely closes it.

internal/grid/handlers.go

@@ -26,6 +26,7 @@ import (
 	"sync"
 
 	"github.com/minio/minio/internal/hash/sha256"
+	xioutil "github.com/minio/minio/internal/ioutil"
 	"github.com/minio/minio/internal/logger"
 	"github.com/tinylib/msgp/msgp"
 )
@@ -579,7 +580,7 @@ func (h *StreamTypeHandler[Payload, Req, Resp]) register(m *Manager, handle func
 				// Don't add extra buffering
 				inT = make(chan Req)
 				go func() {
-					defer close(inT)
+					defer xioutil.SafeClose(inT)
 					for {
 						select {
 						case <-ctx.Done():
@@ -607,7 +608,7 @@ func (h *StreamTypeHandler[Payload, Req, Resp]) register(m *Manager, handle func
 			outT := make(chan Resp)
 			outDone := make(chan struct{})
 			go func() {
-				defer close(outDone)
+				defer xioutil.SafeClose(outDone)
 				dropOutput := false
 				for v := range outT {
 					if dropOutput {
@@ -629,7 +630,7 @@ func (h *StreamTypeHandler[Payload, Req, Resp]) register(m *Manager, handle func
 				}
 			}()
 			rErr := handle(ctx, plT, inT, outT)
-			close(outT)
+			xioutil.SafeClose(outT)
 			<-outDone
 			return rErr
 		}, OutCapacity: h.OutCapacity, InCapacity: h.InCapacity, Subroute: strings.Join(subroute, "/"),
@@ -695,7 +696,7 @@ func (h *StreamTypeHandler[Payload, Req, Resp]) Call(ctx context.Context, c Stre
 			return nil, fmt.Errorf("internal error: stream request channel nil")
 		}
 		go func() {
-			defer close(stream.Requests)
+			defer xioutil.SafeClose(stream.Requests)
 			for req := range reqT {
 				b, err := req.MarshalMsg(GetByteBuffer()[:0])
 				if err != nil {
@@ -706,7 +707,7 @@ func (h *StreamTypeHandler[Payload, Req, Resp]) Call(ctx context.Context, c Stre
 			}
 		}()
 	} else if stream.Requests != nil {
-		close(stream.Requests)
+		xioutil.SafeClose(stream.Requests)
 	}
 
 	return &TypedStream[Req, Resp]{responses: stream, newResp: h.NewResponse, Requests: reqT}, nil