// Adapted from src/debug/pe/file.go: pe.(*File).DWARF()
func dwarfFromPE(f *pe.File) (*dwarf.Data, error) {
// There are many other DWARF sections, but these
// are the ones the debug/dwarf package uses.
// Don't bother loading others.
var names = [...]string{"abbrev", "info", "line", "str"}
var dat [len(names)][]byte
for i, name := range names {
name = ".debug_" + name
s := f.Section(name)
if s == nil {
continue
}
b, err := s.Data()
if err != nil && uint32(len(b)) < s.Size {
return nil, err
}
if 0 < s.VirtualSize && s.VirtualSize < s.Size {
b = b[:s.VirtualSize]
}
dat[i] = b
}
abbrev, info, line, str := dat[0], dat[1], dat[2], dat[3]
return dwarf.New(abbrev, nil, nil, info, line, nil, nil, str)
}
// Borrowed from https://golang.org/src/cmd/internal/objfile/pe.go
func pcln(exe *pe.File) (textStart uint64, symtab, pclntab []byte, err error) {
var imageBase uint64
switch oh := exe.OptionalHeader.(type) {
case *pe.OptionalHeader32:
imageBase = uint64(oh.ImageBase)
case *pe.OptionalHeader64:
imageBase = oh.ImageBase
default:
return 0, nil, nil, fmt.Errorf("pe file format not recognized")
}
if sect := exe.Section(".text"); sect != nil {
textStart = imageBase + uint64(sect.VirtualAddress)
}
if pclntab, err = loadPETable(exe, "runtime.pclntab", "runtime.epclntab"); err != nil {
// We didn't find the symbols, so look for the names used in 1.3 and earlier.
// TODO: Remove code looking for the old symbols when we no longer care about 1.3.
var err2 error
if pclntab, err2 = loadPETable(exe, "pclntab", "epclntab"); err2 != nil {
return 0, nil, nil, err
}
}
if symtab, err = loadPETable(exe, "runtime.symtab", "runtime.esymtab"); err != nil {
// Same as above.
var err2 error
if symtab, err2 = loadPETable(exe, "symtab", "esymtab"); err2 != nil {
return 0, nil, nil, err
}
}
return textStart, symtab, pclntab, nil
}
func (dbp *Process) parseDebugFrame(exe *pe.File, wg *sync.WaitGroup) {
defer wg.Done()
debugFrameSec := exe.Section(".debug_frame")
debugInfoSec := exe.Section(".debug_info")
if debugFrameSec != nil && debugInfoSec != nil {
debugFrame, err := debugFrameSec.Data()
if err != nil && uint32(len(debugFrame)) < debugFrameSec.Size {
fmt.Println("could not get .debug_frame section", err)
os.Exit(1)
}
if 0 < debugFrameSec.VirtualSize && debugFrameSec.VirtualSize < debugFrameSec.Size {
debugFrame = debugFrame[:debugFrameSec.VirtualSize]
}
dat, err := debugInfoSec.Data()
if err != nil {
fmt.Println("could not get .debug_info section", err)
os.Exit(1)
}
dbp.frameEntries = frame.Parse(debugFrame, frame.DwarfEndian(dat))
} else {
fmt.Println("could not find .debug_frame section in binary")
os.Exit(1)
}
}
func (dbp *Process) parseDebugLineInfo(exe *pe.File, wg *sync.WaitGroup) {
defer wg.Done()
if sec := exe.Section(".debug_line"); sec != nil {
debugLine, err := sec.Data()
if err != nil && uint32(len(debugLine)) < sec.Size {
fmt.Println("could not get .debug_line section", err)
os.Exit(1)
}
if 0 < sec.VirtualSize && sec.VirtualSize < sec.Size {
debugLine = debugLine[:sec.VirtualSize]
}
dbp.lineInfo = line.Parse(debugLine)
} else {
fmt.Println("could not find .debug_line section in binary")
os.Exit(1)
}
}
func (dbp *Process) obtainGoSymbols(exe *pe.File, wg *sync.WaitGroup) {
defer wg.Done()
_, symdat, pclndat, err := pcln(exe)
if err != nil {
fmt.Println("could not get Go symbols", err)
os.Exit(1)
}
pcln := gosym.NewLineTable(pclndat, uint64(exe.Section(".text").Offset))
tab, err := gosym.NewTable(symdat, pcln)
if err != nil {
fmt.Println("could not get initialize line table", err)
os.Exit(1)
}
dbp.goSymTable = tab
}