func runObjgraph()

in cmd/viewcore/main.go [540:605]
63 lines of code
11 McCabe index (conditional complexity)

func runObjgraph(cmd *cobra.Command, args []string) {
	_, c, err := readCore()
	if err != nil {
		exitf("%v\n", err)
	}

	fname := args[0]

	// Dump object graph to output file.
	w, err := os.Create(fname)
	if err != nil {
		panic(err)
	}
	fmt.Fprintf(w, "digraph {\n")
	for k, r := range c.Globals() {
		printed := false
		c.ForEachRootPtr(r, func(i int64, y gocore.Object, j int64) bool {
			if !printed {
				fmt.Fprintf(w, "r%d [label=\"%s\n%s\",shape=hexagon]\n", k, r.Name, r.Type)
				printed = true
			}
			fmt.Fprintf(w, "r%d -> o%x [label=\"%s\"", k, c.Addr(y), typeFieldName(r.Type, i))
			if j != 0 {
				fmt.Fprintf(w, " ,headlabel=\"+%d\"", j)
			}
			fmt.Fprintf(w, "]\n")
			return true
		})
	}
	for _, g := range c.Goroutines() {
		last := fmt.Sprintf("o%x", g.Addr())
		for _, f := range g.Frames() {
			frame := fmt.Sprintf("f%x", f.Max())
			fmt.Fprintf(w, "%s [label=\"%s\",shape=rectangle]\n", frame, f.Func().Name())
			fmt.Fprintf(w, "%s -> %s [style=dotted]\n", last, frame)
			last = frame
			for _, r := range f.Roots() {
				c.ForEachRootPtr(r, func(i int64, y gocore.Object, j int64) bool {
					fmt.Fprintf(w, "%s -> o%x [label=\"%s%s\"", frame, c.Addr(y), r.Name, typeFieldName(r.Type, i))
					if j != 0 {
						fmt.Fprintf(w, " ,headlabel=\"+%d\"", j)
					}
					fmt.Fprintf(w, "]\n")
					return true
				})
			}
		}
	}
	c.ForEachObject(func(x gocore.Object) bool {
		addr := c.Addr(x)
		size := c.Size(x)
		fmt.Fprintf(w, "o%x [label=\"%s\\n%d\"]\n", addr, typeName(c, x), size)
		c.ForEachPtr(x, func(i int64, y gocore.Object, j int64) bool {
			fmt.Fprintf(w, "o%x -> o%x [label=\"%s\"", addr, c.Addr(y), fieldName(c, x, i))
			if j != 0 {
				fmt.Fprintf(w, ",headlabel=\"+%d\"", j)
			}
			fmt.Fprintf(w, "]\n")
			return true
		})
		return true
	})
	fmt.Fprintf(w, "}")
	w.Close()
	fmt.Fprintf(os.Stderr, "wrote the object graph to %q\n", fname)
}