Imported Upstream version 1.4upstream/1.4

1 files changed, 94 insertions, 0 deletions

diff --git a/src/cmd/internal/objfile/objfile.go b/src/cmd/internal/objfile/objfile.go
new file mode 100644
index 000000000..9227ef387
--- /dev/null
+++ b/src/cmd/internal/objfile/objfile.go
@@ -0,0 +1,94 @@
+// 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 (
+	"debug/gosym"
+	"fmt"
+	"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
+}
+
+// A File is an opened executable file.
+type File struct {
+	r   *os.File
+	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?
+}
+
+var openers = []func(*os.File) (rawFile, error){
+	openElf,
+	openGoobj,
+	openMacho,
+	openPE,
+	openPlan9,
+}
+
+// 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
+	}
+	for _, try := range openers {
+		if raw, err := try(r); err == nil {
+			return &File{r, 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) Symbols() ([]Sym, error) {
+	syms, err := f.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 (f *File) PCLineTable() (*gosym.Table, error) {
+	textStart, symtab, pclntab, err := f.raw.pcln()
+	if err != nil {
+		return nil, err
+	}
+	return gosym.NewTable(symtab, gosym.NewLineTable(pclntab, textStart))
+}
+
+func (f *File) Text() (uint64, []byte, error) {
+	return f.raw.text()
+}
+
+func (f *File) GOARCH() string {
+	return f.raw.goarch()
+}