Fix a silly bug and add test coverage

.gitignore

@@ -0,0 +1 @@
+coverage.out

transaction.go

@@ -250,13 +250,14 @@ func (t *Transaction) GetEnvList() (map[string]string, error) {
 		t.status = C.PAM_BUF_ERR
 		return nil, t
 	}
-	for *p != nil {
-		chunks := strings.SplitN(C.GoString(*p), "=", 2)
+	q := p
+	for *q != nil {
+		chunks := strings.SplitN(C.GoString(*q), "=", 2)
 		if len(chunks) == 2 {
 			env[chunks[0]] = chunks[1]
 		}
-		C.free(unsafe.Pointer(*p))
-		p = (**C.char)(unsafe.Pointer(uintptr(unsafe.Pointer(p)) + unsafe.Sizeof(p)))
+		C.free(unsafe.Pointer(*q))
+		q = (**C.char)(unsafe.Pointer(uintptr(unsafe.Pointer(q)) + unsafe.Sizeof(*p)))
 	}
 	C.free(unsafe.Pointer(p))
 	return env, nil

transaction_test.go

@@ -99,15 +99,62 @@ func TestPAM_004(t *testing.T) {
 }
 
 func TestGetEnvList(t *testing.T) {
-	tx, err := StartFunc("passwd", "test", func(s Style, msg string) (string, error) {
+	tx, err := StartFunc("", "", func(s Style, msg string) (string, error) {
 		return "", nil
 	})
 	if err != nil {
 		t.Fatalf("start #error: %v", err)
 	}
+
 	m, err := tx.GetEnvList()
 	if err != nil {
 		t.Fatalf("getenvlist #error: %v", err)
 	}
-	t.Log(m)
+	n := len(m)
+	if n != 0 {
+		t.Fatalf("putenv #error: expected 0 items, got %v", n)
+	}
+
+	vals := []string{
+		"VAL1=1",
+		"VAL2=2",
+		"VAL3=3",
+	}
+	for _, s := range vals {
+		err = tx.PutEnv(s)
+		if err != nil {
+			t.Fatalf("putenv #error: %v", err)
+		}
+	}
+
+	s := tx.GetEnv("VAL1")
+	if s != "1" {
+		t.Fatalf("getenv #error: expected 1, got %v", s)
+	}
+	s = tx.GetEnv("VAL2")
+	if s != "2" {
+		t.Fatalf("getenv #error: expected 2, got %v", s)
+	}
+	s = tx.GetEnv("VAL3")
+	if s != "3" {
+		t.Fatalf("getenv #error: expected 3, got %v", s)
+	}
+
+	m, err = tx.GetEnvList()
+	if err != nil {
+		t.Fatalf("getenvlist #error: %v", err)
+	}
+	n = len(m)
+	if n != 3 {
+		t.Fatalf("getenvlist #error: expected 3 items, got %v", n)
+	}
+	if m["VAL1"] != "1" {
+		t.Fatalf("getenvlist #error: expected 1, got %v", m["VAL1"])
+	}
+	if m["VAL2"] != "2" {
+		t.Fatalf("getenvlist #error: expected 2, got %v", m["VAL1"])
+	}
+	if m["VAL3"] != "3" {
+		t.Fatalf("getenvlist #error: expected 3, got %v", m["VAL1"])
+	}
 }