cmd/objdump: works with windows pe executables now

Most code is copy from addr2line change 01dd67e5827f

Update #7406
Fixes #7937

LGTM=iant
R=golang-codereviews, iant, 0intro
CC=golang-codereviews
https://golang.org/cl/95090044

diff --git a/src/cmd/objdump/main.go b/src/cmd/objdump/main.go
index 5602f17d64ee211cf98fdfd2c7f6cc7c94357e16..82b896f44c6be6ffe6eafa831c472964b8819181 100644 (file)
--- a/src/cmd/objdump/main.go
+++ b/src/cmd/objdump/main.go
@@ -170,18 +170,50 @@ func loadTables(f *os.File) (textStart uint64, textData, symtab, pclntab []byte,
                        textStart = uint64(sect.VirtualAddress)
                        textData, _ = sect.Data()
                }
-               if sect := obj.Section(".gosymtab"); sect != nil {
-                       if symtab, err = sect.Data(); err != nil {
-                               return 0, nil, nil, nil, err
-                       }
+               if pclntab, err = loadPETable(obj, "pclntab", "epclntab"); err != nil {
+                       return 0, nil, nil, nil, err
                }
-               if sect := obj.Section(".gopclntab"); sect != nil {
-                       if pclntab, err = sect.Data(); err != nil {
-                               return 0, nil, nil, nil, err
-                       }
+               if symtab, err = loadPETable(obj, "symtab", "esymtab"); err != nil {
+                       return 0, nil, nil, nil, err
                }
                return textStart, textData, symtab, pclntab, nil
        }
 
        return 0, nil, nil, nil, fmt.Errorf("unrecognized binary format")
 }
+
+func findPESymbol(f *pe.File, name string) (*pe.Symbol, error) {
+       for _, s := range f.Symbols {
+               if s.Name != name {
+                       continue
+               }
+               if s.SectionNumber <= 0 {
+                       return nil, fmt.Errorf("symbol %s: invalid section number %d", name, s.SectionNumber)
+               }
+               if len(f.Sections) < int(s.SectionNumber) {
+                       return nil, fmt.Errorf("symbol %s: section number %d is larger than max %d", name, s.SectionNumber, len(f.Sections))
+               }
+               return s, nil
+       }
+       return nil, fmt.Errorf("no %s symbol found", name)
+}
+
+func loadPETable(f *pe.File, sname, ename string) ([]byte, error) {
+       ssym, err := findPESymbol(f, sname)
+       if err != nil {
+               return nil, err
+       }
+       esym, err := findPESymbol(f, ename)
+       if err != nil {
+               return nil, err
+       }
+       if ssym.SectionNumber != esym.SectionNumber {
+               return nil, fmt.Errorf("%s and %s symbols must be in the same section", sname, ename)
+       }
+       sect := f.Sections[ssym.SectionNumber-1]
+       data, err := sect.Data()
+       if err != nil {
+               return nil, err
+       }
+       return data[ssym.Value:esym.Value], nil
+}

diff --git a/src/cmd/objdump/objdump_test.go b/src/cmd/objdump/objdump_test.go
new file mode 100644 (file)
index 0000000..ba2862c
--- /dev/null
+++ b/src/cmd/objdump/objdump_test.go
@@ -0,0 +1,109 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import (
+       "bufio"
+       "bytes"
+       "fmt"
+       "io/ioutil"
+       "os"
+       "os/exec"
+       "path/filepath"
+       "runtime"
+       "strconv"
+       "strings"
+       "testing"
+)
+
+func loadSyms(t *testing.T) map[string]string {
+       cmd := exec.Command("go", "tool", "nm", os.Args[0])
+       out, err := cmd.CombinedOutput()
+       if err != nil {
+               t.Fatalf("go tool nm %v: %v\n%s", os.Args[0], err, string(out))
+       }
+       syms := make(map[string]string)
+       scanner := bufio.NewScanner(bytes.NewReader(out))
+       for scanner.Scan() {
+               f := strings.Fields(scanner.Text())
+               if len(f) < 3 {
+                       continue
+               }
+               syms[f[2]] = f[0]
+       }
+       if err := scanner.Err(); err != nil {
+               t.Fatalf("error reading symbols: %v", err)
+       }
+       return syms
+}
+
+func runObjDump(t *testing.T, exepath, startaddr string) (path, lineno string) {
+       addr, err := strconv.ParseUint(startaddr, 16, 64)
+       if err != nil {
+               t.Fatalf("invalid start address %v: %v", startaddr, err)
+       }
+       endaddr := fmt.Sprintf("%x", addr+10)
+       cmd := exec.Command(exepath, os.Args[0], "0x"+startaddr, "0x"+endaddr)
+       out, err := cmd.CombinedOutput()
+       if err != nil {
+               t.Fatalf("go tool objdump %v: %v\n%s", os.Args[0], err, string(out))
+       }
+       f := strings.Split(string(out), "\n")
+       if len(f) < 1 {
+               t.Fatal("objdump output must have at least one line")
+       }
+       pathAndLineNo := f[0]
+       f = strings.Split(pathAndLineNo, ":")
+       if runtime.GOOS == "windows" {
+               switch len(f) {
+               case 2:
+                       return f[0], f[1]
+               case 3:
+                       return f[0] + ":" + f[1], f[2]
+               default:
+                       t.Fatalf("no line number found in %q", pathAndLineNo)
+               }
+       }
+       if len(f) != 2 {
+               t.Fatalf("no line number found in %q", pathAndLineNo)
+       }
+       return f[0], f[1]
+}
+
+// This is line 75.  The test depends on that.
+func TestObjDump(t *testing.T) {
+       if runtime.GOOS == "plan9" {
+               t.Skip("skipping test; see http://golang.org/issue/7947")
+       }
+       syms := loadSyms(t)
+
+       tmpDir, err := ioutil.TempDir("", "TestObjDump")
+       if err != nil {
+               t.Fatal("TempDir failed: ", err)
+       }
+       defer os.RemoveAll(tmpDir)
+
+       exepath := filepath.Join(tmpDir, "testobjdump.exe")
+       out, err := exec.Command("go", "build", "-o", exepath, "cmd/objdump").CombinedOutput()
+       if err != nil {
+               t.Fatalf("go build -o %v cmd/objdump: %v\n%s", exepath, err, string(out))
+       }
+
+       srcPath, srcLineNo := runObjDump(t, exepath, syms["cmd/objdump.TestObjDump"])
+       fi1, err := os.Stat("objdump_test.go")
+       if err != nil {
+               t.Fatalf("Stat failed: %v", err)
+       }
+       fi2, err := os.Stat(srcPath)
+       if err != nil {
+               t.Fatalf("Stat failed: %v", err)
+       }
+       if !os.SameFile(fi1, fi2) {
+               t.Fatalf("objdump_test.go and %s are not same file", srcPath)
+       }
+       if srcLineNo != "76" {
+               t.Fatalf("line number = %v; want 76", srcLineNo)
+       }
+}