switching to plugins

Signed-off-by: Vincent Batts <vbatts@hashbangbash.com>

walker/func.go

@@ -13,21 +13,24 @@ func LoadPlugin(path string) (Fuzzer, error) {
 	if err != nil {
 		return nil, err
 	}
-	sym, err := p.Lookup("MyFuzzerFunc")
+	sym, err := p.Lookup("NewFuzzer")
 	if err != nil {
-		return nil, err
+		return nil, fmt.Errorf("LoadPlugin: %q", err)
 	}
-	mff, ok := sym.(Fuzzer)
+	nf, ok := sym.(func() (Fuzzer, error))
 	if !ok {
-		return nil, fmt.Errorf("plugin at %q did not provide a FuzzFunc named MyFuzzerFunc", path)
+		return nil, fmt.Errorf("LoadPlugin: plugin at %q did not provide a NewFuzzer function", path)
 	}
-	return mff, nil
+	return nf()
 }
 
+// NewFuzzer initializes a new Fuzzer
+type NewFuzzer func() (Fuzzer, error)
+
 // Fuzzer is a struct that produces a FuzzFunc
 type Fuzzer interface {
 	Name() string
-	Func() FuzzFunc
+	Func(path string, info os.FileInfo, timeout time.Duration) error
 }
 
 // FuzzFunc is like filepath.WalkerFunc, but for poking at `path`

walker/walkers/readFuzz/readFuzz.go

@@ -0,0 +1,42 @@
+package main
+
+import (
+	"fmt"
+	"io"
+	"io/ioutil"
+	"os"
+	"time"
+
+	"git.thisco.de/vbatts/fuzz-walker/walker"
+)
+
+func NewFuzzer() (walker.Fuzzer, error) {
+	return &myFuzzer{}, nil
+}
+
+type myFuzzer struct{}
+
+func (mf myFuzzer) Name() string {
+	return "readFuzz"
+}
+
+func (mf myFuzzer) Func(path string, info os.FileInfo, timeout time.Duration) error {
+	c1 := make(chan error, 1)
+	go func() {
+		fd, err := os.Open(path)
+		if err != nil {
+			c1 <- err
+		}
+		defer fd.Close()
+		_, err = io.Copy(ioutil.Discard, fd)
+		c1 <- err
+	}()
+
+	select {
+	case err := <-c1:
+		return err
+	case <-time.After(timeout):
+		return fmt.Errorf("timeout reached")
+	}
+	return nil
+}