Add a simple tool to generate provider ID's

Also implements the Stringer interface for etw.Provider to output the ID

Signed-off-by: Justin Terry (VM) <juterry@microsoft.com>

internal/etw/provider.go

@@ -4,6 +4,8 @@ import (
 	"bytes"
 	"crypto/sha1"
 	"encoding/binary"
+	"encoding/hex"
+	"fmt"
 	"strings"
 	"unicode/utf16"
 
@@ -25,6 +27,23 @@ type Provider struct {
 	keywordAll uint64
 }
 
+// String returns the `provider`.ID as a string
+func (provider *Provider) String() string {
+	data1 := make([]byte, 4)
+	binary.BigEndian.PutUint32(data1, provider.ID.Data1)
+	data2 := make([]byte, 2)
+	binary.BigEndian.PutUint16(data2, provider.ID.Data2)
+	data3 := make([]byte, 2)
+	binary.BigEndian.PutUint16(data3, provider.ID.Data3)
+	return fmt.Sprintf(
+		"%s-%s-%s-%s-%s",
+		hex.EncodeToString(data1),
+		hex.EncodeToString(data2),
+		hex.EncodeToString(data3),
+		hex.EncodeToString(provider.ID.Data4[:2]),
+		hex.EncodeToString(provider.ID.Data4[2:]))
+}
+
 type providerHandle windows.Handle
 
 // ProviderState informs the provider EnableCallback what action is being

internal/etw/sample/sample.go

@@ -3,8 +3,6 @@ package main
 
 import (
 	"bufio"
-	"encoding/binary"
-	"encoding/hex"
 	"fmt"
 	"os"
 
@@ -18,22 +16,6 @@ func callback(sourceID *windows.GUID, state etw.ProviderState, level etw.Level,
 	fmt.Printf("Callback: isEnabled=%d, level=%d, matchAnyKeyword=%d\n", state, level, matchAnyKeyword)
 }
 
-func guidToString(guid *windows.GUID) string {
-	data1 := make([]byte, 4)
-	binary.BigEndian.PutUint32(data1, guid.Data1)
-	data2 := make([]byte, 2)
-	binary.BigEndian.PutUint16(data2, guid.Data2)
-	data3 := make([]byte, 2)
-	binary.BigEndian.PutUint16(data3, guid.Data3)
-	return fmt.Sprintf(
-		"%s-%s-%s-%s-%s",
-		hex.EncodeToString(data1),
-		hex.EncodeToString(data2),
-		hex.EncodeToString(data3),
-		hex.EncodeToString(guid.Data4[:2]),
-		hex.EncodeToString(guid.Data4[2:]))
-}
-
 func main() {
 	provider, err := etw.NewProvider("TestProvider", callback)
 
@@ -47,7 +29,7 @@ func main() {
 		}
 	}()
 
-	fmt.Println("Provider ID:", guidToString(provider.ID))
+	fmt.Printf("Provider ID: %s\n", provider)
 
 	reader := bufio.NewReader(os.Stdin)
 

tools/etw-provider-gen/main.go

@@ -0,0 +1,25 @@
+package main
+
+import (
+	"flag"
+	"fmt"
+	"os"
+
+	"github.com/Microsoft/go-winio/internal/etw"
+)
+
+func main() {
+	var pn = flag.String("provider-name", "", "The human readable ETW provider name to be converted into GUID format")
+	flag.Parse()
+	if pn == nil || *pn == "" {
+		fmt.Fprint(os.Stderr, "--provider-name is required")
+		os.Exit(1)
+	}
+	p, err := etw.NewProvider(*pn, nil)
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "failed to convert provider-name: '%s' with err: '%s", *pn, err)
+		os.Exit(1)
+	}
+	defer p.Close()
+	fmt.Fprintf(os.Stdout, "%s", p)
+}