debug/debugtracer: add new component debugtracer

DebugTracer can be used for tracing and saving files for debugging
purposes.

1 files changed, 58 insertions, 0 deletions

diff --git a/pkg/debugtracer/debug.go b/pkg/debugtracer/debug.go
new file mode 100644
index 000000000..99a95fd83
--- /dev/null
+++ b/pkg/debugtracer/debug.go
@@ -0,0 +1,58 @@
+// Copyright 2020 syzkaller project authors. All rights reserved.
+// Use of this source code is governed by Apache 2 LICENSE that can be found in the LICENSE file.
+
+package debugtracer
+
+import (
+	"fmt"
+	"io"
+	"path/filepath"
+	"testing"
+
+	"github.com/google/syzkaller/pkg/osutil"
+)
+
+type DebugTracer interface {
+	Log(msg string, args ...interface{})
+	SaveFile(filename string, data []byte)
+}
+
+type GenericTracer struct {
+	TraceWriter io.Writer
+	OutDir      string
+}
+
+type TestTracer struct {
+	T *testing.T
+}
+
+type NullTracer struct {
+}
+
+func (gt *GenericTracer) Log(msg string, args ...interface{}) {
+	fmt.Fprintf(gt.TraceWriter, msg+"\n", args...)
+}
+
+func (gt *GenericTracer) SaveFile(filename string, data []byte) {
+	if gt.OutDir == "" {
+		return
+	}
+	osutil.MkdirAll(gt.OutDir)
+	osutil.WriteFile(filepath.Join(gt.OutDir, filename), data)
+}
+
+func (tt *TestTracer) Log(msg string, args ...interface{}) {
+	tt.T.Log(msg, args)
+}
+
+func (tt *TestTracer) SaveFile(filename string, data []byte) {
+	// Not implemented.
+}
+
+func (nt *NullTracer) Log(msg string, args ...interface{}) {
+	// Not implemented.
+}
+
+func (nt *NullTracer) SaveFile(filename string, data []byte) {
+	// Not implemented.
+}