xrootd: use crypto/rand instead of math/rand

Signed-off-by: Sebastien Binet <binet@cern.ch>

xrootd/file_test.go

@@ -6,9 +6,9 @@ package xrootd // import "go-hep.org/x/hep/xrootd"
 
 import (
 	"context"
+	"crypto/rand"
 	"fmt"
 	"log"
-	"math/rand"
 	"path"
 	"reflect"
 	"testing"
@@ -323,12 +323,6 @@ func TestFile_Stat(t *testing.T) {
 func testFile_StatVirtualFS(t *testing.T, addr string) {
 	t.Parallel()
 
-	want := xrdfs.VirtualFSStat{
-		NumberRW:      1,
-		FreeRW:        444,
-		UtilizationRW: 6,
-	}
-
 	client, err := NewClient(context.Background(), addr, "gopher")
 	if err != nil {
 		t.Fatalf("could not create client: %v", err)
@@ -345,6 +339,12 @@ func testFile_StatVirtualFS(t *testing.T, addr string) {
 	// FIXME: Investigate whether this request is allowed by the protocol: https://github.com/xrootd/xrootd/issues/728
 	t.Skip("Skipping this test because XRootD server probably doesn't support such requests.")
 
+	want := xrdfs.VirtualFSStat{
+		NumberRW:      1,
+		FreeRW:        444,
+		UtilizationRW: 6,
+	}
+
 	got, err := file.StatVirtualFS(context.Background())
 	if err != nil {
 		t.Fatalf("invalid stat call: %v", err)

xrootd/fshandler.go

@@ -5,9 +5,9 @@
 package xrootd // import "go-hep.org/x/hep/xrootd"
 
 import (
+	"crypto/rand"
 	"fmt"
 	"io"
-	"math/rand"
 	"os"
 	"path"
 	"sync"
@@ -146,7 +146,6 @@ func (h *fshandler) Open(sessionID [16]byte, request *open.Request) (xrdproto.Ma
 	// we have appr. 0.7 probability to find a free handle by the random guess.
 	// Then, probability that no free handle is found by 100 tries is something near pow(0.3,100) = 1e-53.
 	for i := 0; i < 100; i++ {
-		// TODO: use crypto/rand under Windows (4 times faster than math/rand) if handle generation is on the hot path.
 		rand.Read(handle[:])
 		if _, dup := sess.handles[handle]; !dup {
 			resp := open.Response{FileHandle: handle}

xrootd/fshandler_test.go

@@ -6,8 +6,8 @@ package xrootd_test // import "go-hep.org/x/hep/xrootd"
 
 import (
 	"context"
+	"crypto/rand"
 	"fmt"
-	"math/rand"
 	"net"
 	"os"
 	"path"