add mutate tool that allows to manually investigate mutator behavior

1 files changed, 49 insertions, 0 deletions

diff --git a/tools/mutate/mutate.go b/tools/mutate/mutate.go
new file mode 100644
index 000000000..353d60390
--- /dev/null
+++ b/tools/mutate/mutate.go
@@ -0,0 +1,49 @@
+// Copyright 2015 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.
+
+// mutates mutates a given program and prints result.
+package main
+
+import (
+	"flag"
+	"fmt"
+	"io/ioutil"
+	"math/rand"
+	"os"
+	"time"
+
+	"github.com/google/syzkaller/prog"
+)
+
+var (
+	flagSeed = flag.Int("seed", -1, "prng seed")
+)
+
+func main() {
+	flag.Parse()
+	if flag.NArg() != 1 {
+		fmt.Fprintf(os.Stderr, "usage: mutate program\n")
+		os.Exit(1)
+	}
+	data, err := ioutil.ReadFile(flag.Arg(0))
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "failed to read prog file: %v\n", err)
+		os.Exit(1)
+	}
+	p, err := prog.Deserialize(data)
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "failed to deserialize the program: %v\n", err)
+		os.Exit(1)
+	}
+
+	prios := prog.CalculatePriorities(nil)
+	ct := prog.BuildChoiceTable(prios, nil)
+
+	seed := time.Now().UnixNano()
+	if *flagSeed != -1 {
+		seed = int64(*flagSeed)
+	}
+	rs := rand.NewSource(seed)
+	p.Mutate(rs, len(p.Calls)+10, ct)
+	fmt.Printf("%s\n", p.Serialize())
+}