cmd/internal/goobj: parse native objects in the archive

Also add HasCGO() to internal/testenv for tests.

Updates #21706

Change-Id: I938188047024052bdb42b3ac1a77708f3c2a6dbb
Reviewed-on: https://go-review.googlesource.com/62591
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

src/cmd/internal/goobj/goobj_test.go

@@ -5,8 +5,12 @@
 package goobj
 
 import (
+	"debug/elf"
+	"debug/macho"
+	"debug/pe"
 	"fmt"
 	"internal/testenv"
+	"io"
 	"io/ioutil"
 	"os"
 	"os/exec"
@@ -16,10 +20,11 @@ import (
 )
 
 var (
-	buildDir  string
-	go1obj    string
-	go2obj    string
-	goarchive string
+	buildDir   string
+	go1obj     string
+	go2obj     string
+	goarchive  string
+	cgoarchive string
 )
 
 func TestMain(m *testing.M) {
@@ -47,6 +52,48 @@ func TestMain(m *testing.M) {
 	os.Exit(exit)
 }
 
+func copyDir(dst, src string) error {
+	err := os.MkdirAll(dst, 0777)
+	if err != nil {
+		return err
+	}
+	fis, err := ioutil.ReadDir(src)
+	if err != nil {
+		return err
+	}
+	for _, fi := range fis {
+		err = copyFile(filepath.Join(dst, fi.Name()), filepath.Join(src, fi.Name()))
+		if err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+func copyFile(dst, src string) (err error) {
+	var s, d *os.File
+	s, err = os.Open(src)
+	if err != nil {
+		return err
+	}
+	defer s.Close()
+	d, err = os.Create(dst)
+	if err != nil {
+		return err
+	}
+	defer func() {
+		e := d.Close()
+		if err == nil {
+			err = e
+		}
+	}()
+	_, err = io.Copy(d, s)
+	if err != nil {
+		return err
+	}
+	return nil
+}
+
 func buildGoobj() error {
 	var err error
 
@@ -80,6 +127,29 @@ func buildGoobj() error {
 		return fmt.Errorf("go tool pack c %s %s %s: %v\n%s", goarchive, go1obj, go2obj, err, out)
 	}
 
+	if testenv.HasCGO() {
+		gopath := filepath.Join(buildDir, "gopath")
+		err = copyDir(filepath.Join(gopath, "src", "mycgo"), filepath.Join("testdata", "mycgo"))
+		if err != nil {
+			return err
+		}
+		cmd := exec.Command(gotool, "install", "mycgo")
+		cmd.Env = append(os.Environ(), "GOPATH="+gopath)
+		out, err = cmd.CombinedOutput()
+		if err != nil {
+			return fmt.Errorf("go install mycgo: %v\n%s", err, out)
+		}
+		pat := filepath.Join(gopath, "pkg", "*", "mycgo.a")
+		ms, err := filepath.Glob(pat)
+		if err != nil {
+			return err
+		}
+		if len(ms) == 0 {
+			return fmt.Errorf("cannot found paths for pattern %s", pat)
+		}
+		cgoarchive = ms[0]
+	}
+
 	return nil
 }
 
@@ -144,3 +214,110 @@ func TestParseArchive(t *testing.T) {
 		t.Errorf(`%s: symbol "mypkg.go2" not found`, path)
 	}
 }
+
+func TestParseCGOArchive(t *testing.T) {
+	testenv.MustHaveCGO(t)
+
+	path := cgoarchive
+
+	f, err := os.Open(path)
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer f.Close()
+
+	p, err := Parse(f, "mycgo")
+	if err != nil {
+		t.Fatal(err)
+	}
+	if p.Arch != runtime.GOARCH {
+		t.Errorf("%s: got %v, want %v", path, p.Arch, runtime.GOARCH)
+	}
+	var found1 bool
+	var found2 bool
+	for _, s := range p.Syms {
+		if s.Name == "mycgo.go1" {
+			found1 = true
+		}
+		if s.Name == "mycgo.go2" {
+			found2 = true
+		}
+	}
+	if !found1 {
+		t.Errorf(`%s: symbol "mycgo.go1" not found`, path)
+	}
+	if !found2 {
+		t.Errorf(`%s: symbol "mycgo.go2" not found`, path)
+	}
+
+	c1 := "c1"
+	c2 := "c2"
+
+	found1 = false
+	found2 = false
+
+	switch runtime.GOOS {
+	case "darwin":
+		c1 = "_" + c1
+		c2 = "_" + c2
+		for _, obj := range p.Native {
+			mf, err := macho.NewFile(obj)
+			if err != nil {
+				t.Fatal(err)
+			}
+			for _, s := range mf.Symtab.Syms {
+				switch s.Name {
+				case c1:
+					found1 = true
+				case c2:
+					found2 = true
+				}
+			}
+		}
+	case "windows":
+		if runtime.GOARCH == "386" {
+			c1 = "_" + c1
+			c2 = "_" + c2
+		}
+		for _, obj := range p.Native {
+			pf, err := pe.NewFile(obj)
+			if err != nil {
+				t.Fatal(err)
+			}
+			for _, s := range pf.Symbols {
+				switch s.Name {
+				case c1:
+					found1 = true
+				case c2:
+					found2 = true
+				}
+			}
+		}
+	default:
+		for _, obj := range p.Native {
+			ef, err := elf.NewFile(obj)
+			if err != nil {
+				t.Fatal(err)
+			}
+			syms, err := ef.Symbols()
+			if err != nil {
+				t.Fatal(err)
+			}
+			for _, s := range syms {
+				switch s.Name {
+				case c1:
+					found1 = true
+				case c2:
+					found2 = true
+				}
+			}
+		}
+	}
+
+	if !found1 {
+		t.Errorf(`%s: symbol %q not found`, path, c1)
+	}
+	if !found2 {
+		t.Errorf(`%s: symbol %q not found`, path, c2)
+	}
+}