Ejemplo n.º 1
0
// Callstack displays an arbitrary path from a root of the callgraph
// to the function at the current position.
//
// The information may be misleading in a context-insensitive
// analysis. e.g. the call path X->Y->Z might be infeasible if Y never
// calls Z when it is called from X.  TODO(adonovan): think about UI.
//
// TODO(adonovan): permit user to specify a starting point other than
// the analysis root.
//
func callstack(o *Oracle, qpos *QueryPos) (queryResult, error) {
	pkg := o.prog.Package(qpos.info.Pkg)
	if pkg == nil {
		return nil, fmt.Errorf("no SSA package")
	}

	if !ssa.HasEnclosingFunction(pkg, qpos.path) {
		return nil, fmt.Errorf("this position is not inside a function")
	}

	buildSSA(o)

	target := ssa.EnclosingFunction(pkg, qpos.path)
	if target == nil {
		return nil, fmt.Errorf("no SSA function built for this location (dead code?)")
	}

	// Run the pointer analysis and build the complete call graph.
	o.ptaConfig.BuildCallGraph = true
	cg := ptrAnalysis(o).CallGraph
	cg.DeleteSyntheticNodes()

	// Search for an arbitrary path from a root to the target function.
	isEnd := func(n *callgraph.Node) bool { return n.Func == target }
	callpath := callgraph.PathSearch(cg.Root, isEnd)
	if callpath != nil {
		callpath = callpath[1:] // remove synthetic edge from <root>
	}

	return &callstackResult{
		qpos:     qpos,
		target:   target,
		callpath: callpath,
	}, nil
}
Ejemplo n.º 2
0
func checkFn(fn *ssa.Function, prog *ssa.Program, ptrResult *pointer.Result, roots []*ssa.Function) {
	nam := fn.String()
	if strings.HasPrefix(strings.TrimPrefix(nam, "("), *prefix) {
		hasPath := false
		usedExternally := false
		for _, r := range roots {
			if r != nil {
				nod, ok := ptrResult.CallGraph.Nodes[r]
				if ok {
					//fmt.Println("NODE root", r.Name())
					pth := callgraph.PathSearch(nod,
						func(n *callgraph.Node) bool {
							if n == nil {
								return false
							}
							if n.Func == fn {
								for _, ine := range n.In {
									if ine.Caller.Func.Pkg != fn.Pkg {
										//fmt.Println("DEBUG diff? ",
										//	ine.Caller.Func.Pkg, fn.Pkg)
										usedExternally = true
										break
									}
								}
								return true
							}
							return false
						})
					if pth != nil {
						//fmt.Printf("DEBUG path from %v to %v = %v\n",
						//	r, fn, pth)
						hasPath = true
						break
					}
				}
			}
		}
		isUpper := unicode.IsUpper(rune(fn.Name()[0]))
		pos := fn.Pos()
		//if strings.HasPrefix(nam, "(") && (!hasPath || (!usedExternally && isUpper)) {
		//	fmt.Println("bad Pos", pos, prog.Fset.Position(pos).String())
		//}
		loc := strings.TrimPrefix(
			prog.Fset.Position(pos).String(),
			gopath+"/src/"+*prefix+"/")
		showFuncResult(loc, nam, hasPath, usedExternally, isUpper)
	}
	wg.Done()
}
Ejemplo n.º 3
0
// Callstack displays an arbitrary path from a root of the callgraph
// to the function at the current position.
//
// The information may be misleading in a context-insensitive
// analysis. e.g. the call path X->Y->Z might be infeasible if Y never
// calls Z when it is called from X.  TODO(adonovan): think about UI.
//
// TODO(adonovan): permit user to specify a starting point other than
// the analysis root.
//
func callstack(q *Query) error {
	fset := token.NewFileSet()
	lconf := loader.Config{Fset: fset, Build: q.Build}

	if err := setPTAScope(&lconf, q.Scope); err != nil {
		return err
	}

	// Load/parse/type-check the program.
	lprog, err := loadWithSoftErrors(&lconf)
	if err != nil {
		return err
	}

	qpos, err := parseQueryPos(lprog, q.Pos, false)
	if err != nil {
		return err
	}

	prog := ssautil.CreateProgram(lprog, 0)

	ptaConfig, err := setupPTA(prog, lprog, q.PTALog, q.Reflection)
	if err != nil {
		return err
	}

	pkg := prog.Package(qpos.info.Pkg)
	if pkg == nil {
		return fmt.Errorf("no SSA package")
	}

	if !ssa.HasEnclosingFunction(pkg, qpos.path) {
		return fmt.Errorf("this position is not inside a function")
	}

	// Defer SSA construction till after errors are reported.
	prog.Build()

	target := ssa.EnclosingFunction(pkg, qpos.path)
	if target == nil {
		return fmt.Errorf("no SSA function built for this location (dead code?)")
	}

	var callpath []*callgraph.Edge
	isEnd := func(n *callgraph.Node) bool { return n.Func == target }

	// First, build a callgraph containing only static call edges,
	// and search for an arbitrary path from a root to the target function.
	// This is quick, and the user wants a static path if one exists.
	cg := static.CallGraph(prog)
	cg.DeleteSyntheticNodes()
	for _, ep := range entryPoints(ptaConfig.Mains) {
		callpath = callgraph.PathSearch(cg.CreateNode(ep), isEnd)
		if callpath != nil {
			break
		}
	}

	// No fully static path found.
	// Run the pointer analysis and build a complete call graph.
	if callpath == nil {
		ptaConfig.BuildCallGraph = true
		cg := ptrAnalysis(ptaConfig).CallGraph
		cg.DeleteSyntheticNodes()
		callpath = callgraph.PathSearch(cg.Root, isEnd)
		if callpath != nil {
			callpath = callpath[1:] // remove synthetic edge from <root>
		}
	}

	q.Output(fset, &callstackResult{
		qpos:     qpos,
		target:   target,
		callpath: callpath,
	})
	return nil
}
Ejemplo n.º 4
0
// Callstack displays an arbitrary path from a root of the callgraph
// to the function at the current position.
//
// The information may be misleading in a context-insensitive
// analysis. e.g. the call path X->Y->Z might be infeasible if Y never
// calls Z when it is called from X.  TODO(adonovan): think about UI.
//
// TODO(adonovan): permit user to specify a starting point other than
// the analysis root.
//
func callstack(q *Query) error {
	fset := token.NewFileSet()
	lconf := loader.Config{Fset: fset, Build: q.Build}

	if err := setPTAScope(&lconf, q.Scope); err != nil {
		return err
	}

	// Load/parse/type-check the program.
	lprog, err := lconf.Load()
	if err != nil {
		return err
	}

	qpos, err := parseQueryPos(lprog, q.Pos, false)
	if err != nil {
		return err
	}

	prog := ssautil.CreateProgram(lprog, 0)

	ptaConfig, err := setupPTA(prog, lprog, q.PTALog, q.Reflection)
	if err != nil {
		return err
	}

	pkg := prog.Package(qpos.info.Pkg)
	if pkg == nil {
		return fmt.Errorf("no SSA package")
	}

	if !ssa.HasEnclosingFunction(pkg, qpos.path) {
		return fmt.Errorf("this position is not inside a function")
	}

	// Defer SSA construction till after errors are reported.
	prog.BuildAll()

	target := ssa.EnclosingFunction(pkg, qpos.path)
	if target == nil {
		return fmt.Errorf("no SSA function built for this location (dead code?)")
	}

	// Run the pointer analysis and build the complete call graph.
	ptaConfig.BuildCallGraph = true
	cg := ptrAnalysis(ptaConfig).CallGraph
	cg.DeleteSyntheticNodes()

	// Search for an arbitrary path from a root to the target function.
	isEnd := func(n *callgraph.Node) bool { return n.Func == target }
	callpath := callgraph.PathSearch(cg.Root, isEnd)
	if callpath != nil {
		callpath = callpath[1:] // remove synthetic edge from <root>
	}

	q.Fset = fset
	q.result = &callstackResult{
		qpos:     qpos,
		target:   target,
		callpath: callpath,
	}
	return nil
}