1 files changed, 186 insertions, 0 deletions
diff --git a/src/cmd/internal/objfile/objfile.go b/src/cmd/internal/objfile/objfile.go
new file mode 100644
index 0000000..d890a0b
--- /dev/null
+++ b/src/cmd/internal/objfile/objfile.go
@@ -0,0 +1,186 @@
+// 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 objfile implements portable access to OS-specific executable files.
+package objfile
+
+import (
+	"cmd/internal/archive"
+	"debug/dwarf"
+	"debug/gosym"
+	"fmt"
+	"io"
+	"os"
+	"sort"
+)
+
+type rawFile interface {
+	symbols() (syms []Sym, err error)
+	pcln() (textStart uint64, symtab, pclntab []byte, err error)
+	text() (textStart uint64, text []byte, err error)
+	goarch() string
+	loadAddress() (uint64, error)
+	dwarf() (*dwarf.Data, error)
+}
+
+// A File is an opened executable file.
+type File struct {
+	r       *os.File
+	entries []*Entry
+}
+
+type Entry struct {
+	name string
+	raw  rawFile
+}
+
+// A Sym is a symbol defined in an executable file.
+type Sym struct {
+	Name   string  // symbol name
+	Addr   uint64  // virtual address of symbol
+	Size   int64   // size in bytes
+	Code   rune    // nm code (T for text, D for data, and so on)
+	Type   string  // XXX?
+	Relocs []Reloc // in increasing Addr order
+}
+
+type Reloc struct {
+	Addr     uint64 // Address of first byte that reloc applies to.
+	Size     uint64 // Number of bytes
+	Stringer RelocStringer
+}
+
+type RelocStringer interface {
+	// insnOffset is the offset of the instruction containing the relocation
+	// from the start of the symbol containing the relocation.
+	String(insnOffset uint64) string
+}
+
+var openers = []func(io.ReaderAt) (rawFile, error){
+	openElf,
+	openMacho,
+	openPE,
+	openPlan9,
+	openXcoff,
+}
+
+// Open opens the named file.
+// The caller must call f.Close when the file is no longer needed.
+func Open(name string) (*File, error) {
+	r, err := os.Open(name)
+	if err != nil {
+		return nil, err
+	}
+	if f, err := openGoFile(r); err == nil {
+		return f, nil
+	} else if _, ok := err.(archive.ErrGoObjOtherVersion); ok {
+		return nil, fmt.Errorf("open %s: %v", name, err)
+	}
+	for _, try := range openers {
+		if raw, err := try(r); err == nil {
+			return &File{r, []*Entry{{raw: raw}}}, nil
+		}
+	}
+	r.Close()
+	return nil, fmt.Errorf("open %s: unrecognized object file", name)
+}
+
+func (f *File) Close() error {
+	return f.r.Close()
+}
+
+func (f *File) Entries() []*Entry {
+	return f.entries
+}
+
+func (f *File) Symbols() ([]Sym, error) {
+	return f.entries[0].Symbols()
+}
+
+func (f *File) PCLineTable() (Liner, error) {
+	return f.entries[0].PCLineTable()
+}
+
+func (f *File) Text() (uint64, []byte, error) {
+	return f.entries[0].Text()
+}
+
+func (f *File) GOARCH() string {
+	return f.entries[0].GOARCH()
+}
+
+func (f *File) LoadAddress() (uint64, error) {
+	return f.entries[0].LoadAddress()
+}
+
+func (f *File) DWARF() (*dwarf.Data, error) {
+	return f.entries[0].DWARF()
+}
+
+func (f *File) Disasm() (*Disasm, error) {
+	return f.entries[0].Disasm()
+}
+
+func (e *Entry) Name() string {
+	return e.name
+}
+
+func (e *Entry) Symbols() ([]Sym, error) {
+	syms, err := e.raw.symbols()
+	if err != nil {
+		return nil, err
+	}
+	sort.Sort(byAddr(syms))
+	return syms, nil
+}
+
+type byAddr []Sym
+
+func (x byAddr) Less(i, j int) bool { return x[i].Addr < x[j].Addr }
+func (x byAddr) Len() int           { return len(x) }
+func (x byAddr) Swap(i, j int)      { x[i], x[j] = x[j], x[i] }
+
+func (e *Entry) PCLineTable() (Liner, error) {
+	// If the raw file implements Liner directly, use that.
+	// Currently, only Go intermediate objects and archives (goobj) use this path.
+	if pcln, ok := e.raw.(Liner); ok {
+		return pcln, nil
+	}
+	// Otherwise, read the pcln tables and build a Liner out of that.
+	textStart, symtab, pclntab, err := e.raw.pcln()
+	if err != nil {
+		return nil, err
+	}
+	syms, err := e.raw.symbols()
+	if err == nil {
+		for _, s := range syms {
+			if s.Name == "runtime.text" {
+				textStart = s.Addr
+				break
+			}
+		}
+	}
+	return gosym.NewTable(symtab, gosym.NewLineTable(pclntab, textStart))
+}
+
+func (e *Entry) Text() (uint64, []byte, error) {
+	return e.raw.text()
+}
+
+func (e *Entry) GOARCH() string {
+	return e.raw.goarch()
+}
+
+// LoadAddress returns the expected load address of the file.
+// This differs from the actual load address for a position-independent
+// executable.
+func (e *Entry) LoadAddress() (uint64, error) {
+	return e.raw.loadAddress()
+}
+
+// DWARF returns DWARF debug data for the file, if any.
+// This is for cmd/pprof to locate cgo functions.
+func (e *Entry) DWARF() (*dwarf.Data, error) {
+	return e.raw.dwarf()
+}