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-rw-r--r--vendor/github.com/google/gops/internal/objfile/objfile.go129
1 files changed, 129 insertions, 0 deletions
diff --git a/vendor/github.com/google/gops/internal/objfile/objfile.go b/vendor/github.com/google/gops/internal/objfile/objfile.go
new file mode 100644
index 00000000..a884a20d
--- /dev/null
+++ b/vendor/github.com/google/gops/internal/objfile/objfile.go
@@ -0,0 +1,129 @@
+// 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/dwarf"
+ "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
+ loadAddress() (uint64, error)
+ dwarf() (*dwarf.Data, error)
+}
+
+// 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?
+ 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(*os.File) (rawFile, error){
+ openElf,
+ // openGoobj, // TODO(jbd): Bring it back when 1.8 is popular.
+ 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() (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 := f.raw.(Liner); ok {
+ return pcln, nil
+ }
+ // Otherwise, read the pcln tables and build a Liner out of that.
+ 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()
+}
+
+// LoadAddress returns the expected load address of the file.
+// This differs from the actual load address for a position-independent
+// executable.
+func (f *File) LoadAddress() (uint64, error) {
+ return f.raw.loadAddress()
+}
+
+// DWARF returns DWARF debug data for the file, if any.
+// This is for cmd/pprof to locate cgo functions.
+func (f *File) DWARF() (*dwarf.Data, error) {
+ return f.raw.dwarf()
+}