mirror of
https://github.com/autc04/Retro68.git
synced 2024-11-29 12:50:35 +00:00
97 lines
2.9 KiB
Go
97 lines
2.9 KiB
Go
// Copyright 2009 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 dwarf provides access to DWARF debugging information loaded from
|
|
// executable files, as defined in the DWARF 2.0 Standard at
|
|
// http://dwarfstd.org/doc/dwarf-2.0.0.pdf
|
|
package dwarf
|
|
|
|
import "encoding/binary"
|
|
|
|
// Data represents the DWARF debugging information
|
|
// loaded from an executable file (for example, an ELF or Mach-O executable).
|
|
type Data struct {
|
|
// raw data
|
|
abbrev []byte
|
|
aranges []byte
|
|
frame []byte
|
|
info []byte
|
|
line []byte
|
|
pubnames []byte
|
|
ranges []byte
|
|
str []byte
|
|
|
|
// parsed data
|
|
abbrevCache map[uint64]abbrevTable
|
|
order binary.ByteOrder
|
|
typeCache map[Offset]Type
|
|
typeSigs map[uint64]*typeUnit
|
|
unit []unit
|
|
}
|
|
|
|
// New returns a new Data object initialized from the given parameters.
|
|
// Rather than calling this function directly, clients should typically use
|
|
// the DWARF method of the File type of the appropriate package debug/elf,
|
|
// debug/macho, debug/pe, or debug/xcoff.
|
|
//
|
|
// The []byte arguments are the data from the corresponding debug section
|
|
// in the object file; for example, for an ELF object, abbrev is the contents of
|
|
// the ".debug_abbrev" section.
|
|
func New(abbrev, aranges, frame, info, line, pubnames, ranges, str []byte) (*Data, error) {
|
|
d := &Data{
|
|
abbrev: abbrev,
|
|
aranges: aranges,
|
|
frame: frame,
|
|
info: info,
|
|
line: line,
|
|
pubnames: pubnames,
|
|
ranges: ranges,
|
|
str: str,
|
|
abbrevCache: make(map[uint64]abbrevTable),
|
|
typeCache: make(map[Offset]Type),
|
|
typeSigs: make(map[uint64]*typeUnit),
|
|
}
|
|
|
|
// Sniff .debug_info to figure out byte order.
|
|
// 32-bit DWARF: 4 byte length, 2 byte version.
|
|
// 64-bit DWARf: 4 bytes of 0xff, 8 byte length, 2 byte version.
|
|
if len(d.info) < 6 {
|
|
return nil, DecodeError{"info", Offset(len(d.info)), "too short"}
|
|
}
|
|
offset := 4
|
|
if d.info[0] == 0xff && d.info[1] == 0xff && d.info[2] == 0xff && d.info[3] == 0xff {
|
|
if len(d.info) < 14 {
|
|
return nil, DecodeError{"info", Offset(len(d.info)), "too short"}
|
|
}
|
|
offset = 12
|
|
}
|
|
// Fetch the version, a tiny 16-bit number (1, 2, 3, 4, 5).
|
|
x, y := d.info[offset], d.info[offset+1]
|
|
switch {
|
|
case x == 0 && y == 0:
|
|
return nil, DecodeError{"info", 4, "unsupported version 0"}
|
|
case x == 0:
|
|
d.order = binary.BigEndian
|
|
case y == 0:
|
|
d.order = binary.LittleEndian
|
|
default:
|
|
return nil, DecodeError{"info", 4, "cannot determine byte order"}
|
|
}
|
|
|
|
u, err := d.parseUnits()
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
d.unit = u
|
|
return d, nil
|
|
}
|
|
|
|
// AddTypes will add one .debug_types section to the DWARF data. A
|
|
// typical object with DWARF version 4 debug info will have multiple
|
|
// .debug_types sections. The name is used for error reporting only,
|
|
// and serves to distinguish one .debug_types section from another.
|
|
func (d *Data) AddTypes(name string, types []byte) error {
|
|
return d.parseTypes(name, types)
|
|
}
|