Stop passing Go pointers to C

callback.go

@@ -0,0 +1,30 @@
+package pam
+
+import "sync"
+
+var cb struct {
+	sync.Mutex
+	m map[int]interface{}
+	c int
+}
+
+func cbAdd(v interface{}) int {
+	cb.Lock()
+	defer cb.Unlock()
+	if cb.m == nil {
+		cb.m = make(map[int]interface{})
+	}
+	cb.c++
+	cb.m[cb.c] = v
+	return cb.c
+}
+
+func cbGet(c int) interface{} {
+	cb.Lock()
+	defer cb.Unlock()
+	v := cb.m[c]
+	if v == nil {
+		panic("Callback pointer not found")
+	}
+	return v
+}