// TestCHA runs CHA on each file in inputs, prints the dynamic edges of
// the call graph, and compares it with the golden results embedded in
// the WANT comment at the end of the file.
//
func TestCHA(t *testing.T) {
for _, filename := range inputs {
content, err := ioutil.ReadFile(filename)
if err != nil {
t.Errorf("couldn't read file '%s': %s", filename, err)
continue
}
conf := loader.Config{
SourceImports: true,
ParserMode: parser.ParseComments,
}
f, err := conf.ParseFile(filename, content)
if err != nil {
t.Error(err)
continue
}
want, pos := expectation(f)
if pos == token.NoPos {
t.Errorf("No WANT: comment in %s", filename)
continue
}
conf.CreateFromFiles("main", f)
iprog, err := conf.Load()
if err != nil {
t.Error(err)
continue
}
prog := ssa.Create(iprog, 0)
mainPkg := prog.Package(iprog.Created[0].Pkg)
prog.BuildAll()
cg := cha.CallGraph(prog)
if got := printGraph(cg, mainPkg.Object); got != want {
t.Errorf("%s: got:\n%s\nwant:\n%s",
prog.Fset.Position(pos), got, want)
}
}
}
// GetNodes returns the D3-compatible nodes by cha analysis -
// notably, works without a main()
func GetNodes(prog *ssa.Program) ([]node.Node, error) {
added := make(map[string]struct{})
extraImports := make(map[string][]string)
var nodes []node.Node
callgraph := cha.CallGraph(prog)
callgraph.DeleteSyntheticNodes()
for f, bar := range callgraph.Nodes {
fName := fmt.Sprintf("%+v", f)
_, ok := added[fName]
if !ok {
for _, edge := range bar.Out {
if extraImports[edge.Callee.Func.String()] == nil {
extraImports[edge.Callee.Func.String()] = make([]string, 0)
}
extraImports[edge.Callee.Func.String()] = append(extraImports[edge.Callee.Func.String()], strings.TrimPrefix(slug.Slug(fName), "package-"))
}
added[fName] = struct{}{}
}
}
added = make(map[string]struct{})
for f, bar := range callgraph.Nodes {
fName := fmt.Sprintf("%+v", f)
_, ok := added[fName]
if !ok {
var imports []string
for _, edge := range bar.In {
imports = append(imports, strings.TrimPrefix(slug.Slug(edge.Caller.Func.String()), "package-"))
}
imports = append(imports, extraImports[fName]...)
nodes = append(nodes, node.Node{Name: strings.TrimPrefix(slug.Slug(fName), "package-"), Imports: imports, Size: len(imports) * 100})
added[fName] = struct{}{}
}
}
return nodes, nil
}
func doCallgraph(ctxt *build.Context, algo, format string, tests bool, args []string) error {
conf := loader.Config{
Build: ctxt,
SourceImports: true,
}
if len(args) == 0 {
fmt.Fprintln(os.Stderr, Usage)
return nil
}
// Use the initial packages from the command line.
args, err := conf.FromArgs(args, tests)
if err != nil {
return err
}
// Load, parse and type-check the whole program.
iprog, err := conf.Load()
if err != nil {
return err
}
// Create and build SSA-form program representation.
prog := ssa.Create(iprog, 0)
prog.BuildAll()
// -- call graph construction ------------------------------------------
var cg *callgraph.Graph
switch algo {
case "static":
cg = static.CallGraph(prog)
case "cha":
cg = cha.CallGraph(prog)
case "pta":
main, err := mainPackage(prog, tests)
if err != nil {
return err
}
config := &pointer.Config{
Mains: []*ssa.Package{main},
BuildCallGraph: true,
}
ptares, err := pointer.Analyze(config)
if err != nil {
return err // internal error in pointer analysis
}
cg = ptares.CallGraph
case "rta":
main, err := mainPackage(prog, tests)
if err != nil {
return err
}
roots := []*ssa.Function{
main.Func("init"),
main.Func("main"),
}
rtares := rta.Analyze(roots, true)
cg = rtares.CallGraph
// NB: RTA gives us Reachable and RuntimeTypes too.
default:
return fmt.Errorf("unknown algorithm: %s", algo)
}
cg.DeleteSyntheticNodes()
// -- output------------------------------------------------------------
var before, after string
// Pre-canned formats.
switch format {
case "digraph":
format = `{{printf "%q %q" .Caller .Callee}}`
case "graphviz":
before = "digraph callgraph {\n"
after = "}\n"
format = ` {{printf "%q" .Caller}} -> {{printf "%q" .Callee}}"`
}
tmpl, err := template.New("-format").Parse(format)
if err != nil {
return fmt.Errorf("invalid -format template: %v", err)
}
// Allocate these once, outside the traversal.
var buf bytes.Buffer
data := Edge{fset: prog.Fset}
fmt.Fprint(stdout, before)
if err := callgraph.GraphVisitEdges(cg, func(edge *callgraph.Edge) error {
data.position.Offset = -1
data.edge = edge
data.Caller = edge.Caller.Func
data.Callee = edge.Callee.Func
buf.Reset()
if err := tmpl.Execute(&buf, &data); err != nil {
return err
}
stdout.Write(buf.Bytes())
if len := buf.Len(); len == 0 || buf.Bytes()[len-1] != '\n' {
fmt.Fprintln(stdout)
}
return nil
}); err != nil {
return err
}
fmt.Fprint(stdout, after)
return nil
}
func doCallgraph(ctxt *build.Context, algo, format string, tests bool, args []string) error {
conf := loader.Config{Build: ctxt}
if len(args) == 0 {
fmt.Fprintln(os.Stderr, Usage)
return nil
}
if *fileFlag == "" || *lineFlag == -1 {
fmt.Fprintln(os.Stderr, "Need input file and line")
return nil
}
// Use the initial packages from the command line.
args, err := conf.FromArgs(args, tests)
if err != nil {
return err
}
// Load, parse and type-check the whole program.
iprog, err := conf.Load()
if err != nil {
return err
}
// Create and build SSA-form program representation.
prog := ssautil.CreateProgram(iprog, 0)
prog.Build()
// -- call graph construction ------------------------------------------
var cg *callgraph.Graph
switch algo {
case "static":
cg = static.CallGraph(prog)
case "cha":
cg = cha.CallGraph(prog)
case "pta":
// Set up points-to analysis log file.
var ptalog io.Writer
if *ptalogFlag != "" {
if f, err := os.Create(*ptalogFlag); err != nil {
log.Fatalf("Failed to create PTA log file: %s", err)
} else {
buf := bufio.NewWriter(f)
ptalog = buf
defer func() {
if err := buf.Flush(); err != nil {
log.Printf("flush: %s", err)
}
if err := f.Close(); err != nil {
log.Printf("close: %s", err)
}
}()
}
}
main, err := mainPackage(prog, tests)
if err != nil {
return err
}
config := &pointer.Config{
Mains: []*ssa.Package{main},
BuildCallGraph: true,
Log: ptalog,
}
ptares, err := pointer.Analyze(config)
if err != nil {
return err // internal error in pointer analysis
}
cg = ptares.CallGraph
case "rta":
main, err := mainPackage(prog, tests)
if err != nil {
return err
}
roots := []*ssa.Function{
main.Func("init"),
main.Func("main"),
}
rtares := rta.Analyze(roots, true)
cg = rtares.CallGraph
// NB: RTA gives us Reachable and RuntimeTypes too.
default:
return fmt.Errorf("unknown algorithm: %s", algo)
}
cg.DeleteSyntheticNodes()
// -- output------------------------------------------------------------
file := *fileFlag
line := *lineFlag
depth := *depthFlag
node := findFunction(cg, file, line)
if node == nil {
panic("function not found")
}
ins, before := ChainBefore(node)
after, outs := ChainAfter(node)
chain := append(before, after[1:]...)
sort.Sort(SortNodes(ins))
for _, n := range ins {
_, ch := ChainBefore(n)
fmt.Printf("(%d) %s\n", impact(ch[0]), chainToString(ch))
}
fmt.Println()
fmt.Println(chainToString(chain))
fmt.Println()
sort.Sort(SortNodes(outs))
for _, n := range outs {
if impact(n) > minImpact {
continue
}
printFanout(depth, "", n)
}
return nil
}