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Diffstat (limited to 'gcc-4.8.1/libgo/go/debug/elf/file.go')
-rw-r--r--gcc-4.8.1/libgo/go/debug/elf/file.go775
1 files changed, 0 insertions, 775 deletions
diff --git a/gcc-4.8.1/libgo/go/debug/elf/file.go b/gcc-4.8.1/libgo/go/debug/elf/file.go
deleted file mode 100644
index eb3d72f71..000000000
--- a/gcc-4.8.1/libgo/go/debug/elf/file.go
+++ /dev/null
@@ -1,775 +0,0 @@
-// 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 elf implements access to ELF object files.
-package elf
-
-import (
- "bytes"
- "debug/dwarf"
- "encoding/binary"
- "errors"
- "fmt"
- "io"
- "os"
-)
-
-// TODO: error reporting detail
-
-/*
- * Internal ELF representation
- */
-
-// A FileHeader represents an ELF file header.
-type FileHeader struct {
- Class Class
- Data Data
- Version Version
- OSABI OSABI
- ABIVersion uint8
- ByteOrder binary.ByteOrder
- Type Type
- Machine Machine
- Entry uint64
-}
-
-// A File represents an open ELF file.
-type File struct {
- FileHeader
- Sections []*Section
- Progs []*Prog
- closer io.Closer
- gnuNeed []verneed
- gnuVersym []byte
-}
-
-// A SectionHeader represents a single ELF section header.
-type SectionHeader struct {
- Name string
- Type SectionType
- Flags SectionFlag
- Addr uint64
- Offset uint64
- Size uint64
- Link uint32
- Info uint32
- Addralign uint64
- Entsize uint64
-}
-
-// A Section represents a single section in an ELF file.
-type Section struct {
- SectionHeader
-
- // Embed ReaderAt for ReadAt method.
- // Do not embed SectionReader directly
- // to avoid having Read and Seek.
- // If a client wants Read and Seek it must use
- // Open() to avoid fighting over the seek offset
- // with other clients.
- io.ReaderAt
- sr *io.SectionReader
-}
-
-// Data reads and returns the contents of the ELF section.
-func (s *Section) Data() ([]byte, error) {
- dat := make([]byte, s.sr.Size())
- n, err := s.sr.ReadAt(dat, 0)
- return dat[0:n], err
-}
-
-// stringTable reads and returns the string table given by the
-// specified link value.
-func (f *File) stringTable(link uint32) ([]byte, error) {
- if link <= 0 || link >= uint32(len(f.Sections)) {
- return nil, errors.New("section has invalid string table link")
- }
- return f.Sections[link].Data()
-}
-
-// Open returns a new ReadSeeker reading the ELF section.
-func (s *Section) Open() io.ReadSeeker { return io.NewSectionReader(s.sr, 0, 1<<63-1) }
-
-// A ProgHeader represents a single ELF program header.
-type ProgHeader struct {
- Type ProgType
- Flags ProgFlag
- Off uint64
- Vaddr uint64
- Paddr uint64
- Filesz uint64
- Memsz uint64
- Align uint64
-}
-
-// A Prog represents a single ELF program header in an ELF binary.
-type Prog struct {
- ProgHeader
-
- // Embed ReaderAt for ReadAt method.
- // Do not embed SectionReader directly
- // to avoid having Read and Seek.
- // If a client wants Read and Seek it must use
- // Open() to avoid fighting over the seek offset
- // with other clients.
- io.ReaderAt
- sr *io.SectionReader
-}
-
-// Open returns a new ReadSeeker reading the ELF program body.
-func (p *Prog) Open() io.ReadSeeker { return io.NewSectionReader(p.sr, 0, 1<<63-1) }
-
-// A Symbol represents an entry in an ELF symbol table section.
-type Symbol struct {
- Name string
- Info, Other byte
- Section SectionIndex
- Value, Size uint64
-}
-
-/*
- * ELF reader
- */
-
-type FormatError struct {
- off int64
- msg string
- val interface{}
-}
-
-func (e *FormatError) Error() string {
- msg := e.msg
- if e.val != nil {
- msg += fmt.Sprintf(" '%v' ", e.val)
- }
- msg += fmt.Sprintf("in record at byte %#x", e.off)
- return msg
-}
-
-// Open opens the named file using os.Open and prepares it for use as an ELF binary.
-func Open(name string) (*File, error) {
- f, err := os.Open(name)
- if err != nil {
- return nil, err
- }
- ff, err := NewFile(f)
- if err != nil {
- f.Close()
- return nil, err
- }
- ff.closer = f
- return ff, nil
-}
-
-// Close closes the File.
-// If the File was created using NewFile directly instead of Open,
-// Close has no effect.
-func (f *File) Close() error {
- var err error
- if f.closer != nil {
- err = f.closer.Close()
- f.closer = nil
- }
- return err
-}
-
-// SectionByType returns the first section in f with the
-// given type, or nil if there is no such section.
-func (f *File) SectionByType(typ SectionType) *Section {
- for _, s := range f.Sections {
- if s.Type == typ {
- return s
- }
- }
- return nil
-}
-
-// NewFile creates a new File for accessing an ELF binary in an underlying reader.
-// The ELF binary is expected to start at position 0 in the ReaderAt.
-func NewFile(r io.ReaderAt) (*File, error) {
- sr := io.NewSectionReader(r, 0, 1<<63-1)
- // Read and decode ELF identifier
- var ident [16]uint8
- if _, err := r.ReadAt(ident[0:], 0); err != nil {
- return nil, err
- }
- if ident[0] != '\x7f' || ident[1] != 'E' || ident[2] != 'L' || ident[3] != 'F' {
- return nil, &FormatError{0, "bad magic number", ident[0:4]}
- }
-
- f := new(File)
- f.Class = Class(ident[EI_CLASS])
- switch f.Class {
- case ELFCLASS32:
- case ELFCLASS64:
- // ok
- default:
- return nil, &FormatError{0, "unknown ELF class", f.Class}
- }
-
- f.Data = Data(ident[EI_DATA])
- switch f.Data {
- case ELFDATA2LSB:
- f.ByteOrder = binary.LittleEndian
- case ELFDATA2MSB:
- f.ByteOrder = binary.BigEndian
- default:
- return nil, &FormatError{0, "unknown ELF data encoding", f.Data}
- }
-
- f.Version = Version(ident[EI_VERSION])
- if f.Version != EV_CURRENT {
- return nil, &FormatError{0, "unknown ELF version", f.Version}
- }
-
- f.OSABI = OSABI(ident[EI_OSABI])
- f.ABIVersion = ident[EI_ABIVERSION]
-
- // Read ELF file header
- var phoff int64
- var phentsize, phnum int
- var shoff int64
- var shentsize, shnum, shstrndx int
- shstrndx = -1
- switch f.Class {
- case ELFCLASS32:
- hdr := new(Header32)
- sr.Seek(0, os.SEEK_SET)
- if err := binary.Read(sr, f.ByteOrder, hdr); err != nil {
- return nil, err
- }
- f.Type = Type(hdr.Type)
- f.Machine = Machine(hdr.Machine)
- f.Entry = uint64(hdr.Entry)
- if v := Version(hdr.Version); v != f.Version {
- return nil, &FormatError{0, "mismatched ELF version", v}
- }
- phoff = int64(hdr.Phoff)
- phentsize = int(hdr.Phentsize)
- phnum = int(hdr.Phnum)
- shoff = int64(hdr.Shoff)
- shentsize = int(hdr.Shentsize)
- shnum = int(hdr.Shnum)
- shstrndx = int(hdr.Shstrndx)
- case ELFCLASS64:
- hdr := new(Header64)
- sr.Seek(0, os.SEEK_SET)
- if err := binary.Read(sr, f.ByteOrder, hdr); err != nil {
- return nil, err
- }
- f.Type = Type(hdr.Type)
- f.Machine = Machine(hdr.Machine)
- f.Entry = uint64(hdr.Entry)
- if v := Version(hdr.Version); v != f.Version {
- return nil, &FormatError{0, "mismatched ELF version", v}
- }
- phoff = int64(hdr.Phoff)
- phentsize = int(hdr.Phentsize)
- phnum = int(hdr.Phnum)
- shoff = int64(hdr.Shoff)
- shentsize = int(hdr.Shentsize)
- shnum = int(hdr.Shnum)
- shstrndx = int(hdr.Shstrndx)
- }
-
- if shnum > 0 && shoff > 0 && (shstrndx < 0 || shstrndx >= shnum) {
- return nil, &FormatError{0, "invalid ELF shstrndx", shstrndx}
- }
-
- // Read program headers
- f.Progs = make([]*Prog, phnum)
- for i := 0; i < phnum; i++ {
- off := phoff + int64(i)*int64(phentsize)
- sr.Seek(off, os.SEEK_SET)
- p := new(Prog)
- switch f.Class {
- case ELFCLASS32:
- ph := new(Prog32)
- if err := binary.Read(sr, f.ByteOrder, ph); err != nil {
- return nil, err
- }
- p.ProgHeader = ProgHeader{
- Type: ProgType(ph.Type),
- Flags: ProgFlag(ph.Flags),
- Off: uint64(ph.Off),
- Vaddr: uint64(ph.Vaddr),
- Paddr: uint64(ph.Paddr),
- Filesz: uint64(ph.Filesz),
- Memsz: uint64(ph.Memsz),
- Align: uint64(ph.Align),
- }
- case ELFCLASS64:
- ph := new(Prog64)
- if err := binary.Read(sr, f.ByteOrder, ph); err != nil {
- return nil, err
- }
- p.ProgHeader = ProgHeader{
- Type: ProgType(ph.Type),
- Flags: ProgFlag(ph.Flags),
- Off: uint64(ph.Off),
- Vaddr: uint64(ph.Vaddr),
- Paddr: uint64(ph.Paddr),
- Filesz: uint64(ph.Filesz),
- Memsz: uint64(ph.Memsz),
- Align: uint64(ph.Align),
- }
- }
- p.sr = io.NewSectionReader(r, int64(p.Off), int64(p.Filesz))
- p.ReaderAt = p.sr
- f.Progs[i] = p
- }
-
- // Read section headers
- f.Sections = make([]*Section, shnum)
- names := make([]uint32, shnum)
- for i := 0; i < shnum; i++ {
- off := shoff + int64(i)*int64(shentsize)
- sr.Seek(off, os.SEEK_SET)
- s := new(Section)
- switch f.Class {
- case ELFCLASS32:
- sh := new(Section32)
- if err := binary.Read(sr, f.ByteOrder, sh); err != nil {
- return nil, err
- }
- names[i] = sh.Name
- s.SectionHeader = SectionHeader{
- Type: SectionType(sh.Type),
- Flags: SectionFlag(sh.Flags),
- Addr: uint64(sh.Addr),
- Offset: uint64(sh.Off),
- Size: uint64(sh.Size),
- Link: uint32(sh.Link),
- Info: uint32(sh.Info),
- Addralign: uint64(sh.Addralign),
- Entsize: uint64(sh.Entsize),
- }
- case ELFCLASS64:
- sh := new(Section64)
- if err := binary.Read(sr, f.ByteOrder, sh); err != nil {
- return nil, err
- }
- names[i] = sh.Name
- s.SectionHeader = SectionHeader{
- Type: SectionType(sh.Type),
- Flags: SectionFlag(sh.Flags),
- Offset: uint64(sh.Off),
- Size: uint64(sh.Size),
- Addr: uint64(sh.Addr),
- Link: uint32(sh.Link),
- Info: uint32(sh.Info),
- Addralign: uint64(sh.Addralign),
- Entsize: uint64(sh.Entsize),
- }
- }
- s.sr = io.NewSectionReader(r, int64(s.Offset), int64(s.Size))
- s.ReaderAt = s.sr
- f.Sections[i] = s
- }
-
- if len(f.Sections) == 0 {
- return f, nil
- }
-
- // Load section header string table.
- shstrtab, err := f.Sections[shstrndx].Data()
- if err != nil {
- return nil, err
- }
- for i, s := range f.Sections {
- var ok bool
- s.Name, ok = getString(shstrtab, int(names[i]))
- if !ok {
- return nil, &FormatError{shoff + int64(i*shentsize), "bad section name index", names[i]}
- }
- }
-
- return f, nil
-}
-
-// getSymbols returns a slice of Symbols from parsing the symbol table
-// with the given type, along with the associated string table.
-func (f *File) getSymbols(typ SectionType) ([]Symbol, []byte, error) {
- switch f.Class {
- case ELFCLASS64:
- return f.getSymbols64(typ)
-
- case ELFCLASS32:
- return f.getSymbols32(typ)
- }
-
- return nil, nil, errors.New("not implemented")
-}
-
-func (f *File) getSymbols32(typ SectionType) ([]Symbol, []byte, error) {
- symtabSection := f.SectionByType(typ)
- if symtabSection == nil {
- return nil, nil, errors.New("no symbol section")
- }
-
- data, err := symtabSection.Data()
- if err != nil {
- return nil, nil, errors.New("cannot load symbol section")
- }
- symtab := bytes.NewBuffer(data)
- if symtab.Len()%Sym32Size != 0 {
- return nil, nil, errors.New("length of symbol section is not a multiple of SymSize")
- }
-
- strdata, err := f.stringTable(symtabSection.Link)
- if err != nil {
- return nil, nil, errors.New("cannot load string table section")
- }
-
- symbols := make([]Symbol, symtab.Len()/Sym32Size)
-
- i := 0
- var sym Sym32
- for symtab.Len() > 0 {
- binary.Read(symtab, f.ByteOrder, &sym)
- str, _ := getString(strdata, int(sym.Name))
- symbols[i].Name = str
- symbols[i].Info = sym.Info
- symbols[i].Other = sym.Other
- symbols[i].Section = SectionIndex(sym.Shndx)
- symbols[i].Value = uint64(sym.Value)
- symbols[i].Size = uint64(sym.Size)
- i++
- }
-
- return symbols, strdata, nil
-}
-
-func (f *File) getSymbols64(typ SectionType) ([]Symbol, []byte, error) {
- symtabSection := f.SectionByType(typ)
- if symtabSection == nil {
- return nil, nil, errors.New("no symbol section")
- }
-
- data, err := symtabSection.Data()
- if err != nil {
- return nil, nil, errors.New("cannot load symbol section")
- }
- symtab := bytes.NewBuffer(data)
- if symtab.Len()%Sym64Size != 0 {
- return nil, nil, errors.New("length of symbol section is not a multiple of Sym64Size")
- }
-
- strdata, err := f.stringTable(symtabSection.Link)
- if err != nil {
- return nil, nil, errors.New("cannot load string table section")
- }
-
- symbols := make([]Symbol, symtab.Len()/Sym64Size)
-
- i := 0
- var sym Sym64
- for symtab.Len() > 0 {
- binary.Read(symtab, f.ByteOrder, &sym)
- str, _ := getString(strdata, int(sym.Name))
- symbols[i].Name = str
- symbols[i].Info = sym.Info
- symbols[i].Other = sym.Other
- symbols[i].Section = SectionIndex(sym.Shndx)
- symbols[i].Value = sym.Value
- symbols[i].Size = sym.Size
- i++
- }
-
- return symbols, strdata, nil
-}
-
-// getString extracts a string from an ELF string table.
-func getString(section []byte, start int) (string, bool) {
- if start < 0 || start >= len(section) {
- return "", false
- }
-
- for end := start; end < len(section); end++ {
- if section[end] == 0 {
- return string(section[start:end]), true
- }
- }
- return "", false
-}
-
-// Section returns a section with the given name, or nil if no such
-// section exists.
-func (f *File) Section(name string) *Section {
- for _, s := range f.Sections {
- if s.Name == name {
- return s
- }
- }
- return nil
-}
-
-// applyRelocations applies relocations to dst. rels is a relocations section
-// in RELA format.
-func (f *File) applyRelocations(dst []byte, rels []byte) error {
- if f.Class == ELFCLASS64 && f.Machine == EM_X86_64 {
- return f.applyRelocationsAMD64(dst, rels)
- }
-
- return errors.New("not implemented")
-}
-
-func (f *File) applyRelocationsAMD64(dst []byte, rels []byte) error {
- if len(rels)%Sym64Size != 0 {
- return errors.New("length of relocation section is not a multiple of Sym64Size")
- }
-
- symbols, _, err := f.getSymbols(SHT_SYMTAB)
- if err != nil {
- return err
- }
-
- b := bytes.NewBuffer(rels)
- var rela Rela64
-
- for b.Len() > 0 {
- binary.Read(b, f.ByteOrder, &rela)
- symNo := rela.Info >> 32
- t := R_X86_64(rela.Info & 0xffff)
-
- if symNo >= uint64(len(symbols)) {
- continue
- }
- sym := &symbols[symNo]
- if SymType(sym.Info&0xf) != STT_SECTION {
- // We don't handle non-section relocations for now.
- continue
- }
-
- switch t {
- case R_X86_64_64:
- if rela.Off+8 >= uint64(len(dst)) || rela.Addend < 0 {
- continue
- }
- f.ByteOrder.PutUint64(dst[rela.Off:rela.Off+8], uint64(rela.Addend))
- case R_X86_64_32:
- if rela.Off+4 >= uint64(len(dst)) || rela.Addend < 0 {
- continue
- }
- f.ByteOrder.PutUint32(dst[rela.Off:rela.Off+4], uint32(rela.Addend))
- }
- }
-
- return nil
-}
-
-func (f *File) DWARF() (*dwarf.Data, error) {
- // There are many other DWARF sections, but these
- // are the required ones, and the debug/dwarf package
- // does not use the others, so don't bother loading them.
- var names = [...]string{"abbrev", "info", "line", "ranges", "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 && uint64(len(b)) < s.Size {
- return nil, err
- }
- dat[i] = b
- }
-
- // If there's a relocation table for .debug_info, we have to process it
- // now otherwise the data in .debug_info is invalid for x86-64 objects.
- rela := f.Section(".rela.debug_info")
- if rela != nil && rela.Type == SHT_RELA && f.Machine == EM_X86_64 {
- data, err := rela.Data()
- if err != nil {
- return nil, err
- }
- err = f.applyRelocations(dat[1], data)
- if err != nil {
- return nil, err
- }
- }
-
- abbrev, info, line, ranges, str := dat[0], dat[1], dat[2], dat[3], dat[4]
- return dwarf.New(abbrev, nil, nil, info, line, nil, ranges, str)
-}
-
-// Symbols returns the symbol table for f.
-func (f *File) Symbols() ([]Symbol, error) {
- sym, _, err := f.getSymbols(SHT_SYMTAB)
- return sym, err
-}
-
-type ImportedSymbol struct {
- Name string
- Version string
- Library string
-}
-
-// ImportedSymbols returns the names of all symbols
-// referred to by the binary f that are expected to be
-// satisfied by other libraries at dynamic load time.
-// It does not return weak symbols.
-func (f *File) ImportedSymbols() ([]ImportedSymbol, error) {
- sym, str, err := f.getSymbols(SHT_DYNSYM)
- if err != nil {
- return nil, err
- }
- f.gnuVersionInit(str)
- var all []ImportedSymbol
- for i, s := range sym {
- if ST_BIND(s.Info) == STB_GLOBAL && s.Section == SHN_UNDEF {
- all = append(all, ImportedSymbol{Name: s.Name})
- f.gnuVersion(i, &all[len(all)-1])
- }
- }
- return all, nil
-}
-
-type verneed struct {
- File string
- Name string
-}
-
-// gnuVersionInit parses the GNU version tables
-// for use by calls to gnuVersion.
-func (f *File) gnuVersionInit(str []byte) {
- // Accumulate verneed information.
- vn := f.SectionByType(SHT_GNU_VERNEED)
- if vn == nil {
- return
- }
- d, _ := vn.Data()
-
- var need []verneed
- i := 0
- for {
- if i+16 > len(d) {
- break
- }
- vers := f.ByteOrder.Uint16(d[i : i+2])
- if vers != 1 {
- break
- }
- cnt := f.ByteOrder.Uint16(d[i+2 : i+4])
- fileoff := f.ByteOrder.Uint32(d[i+4 : i+8])
- aux := f.ByteOrder.Uint32(d[i+8 : i+12])
- next := f.ByteOrder.Uint32(d[i+12 : i+16])
- file, _ := getString(str, int(fileoff))
-
- var name string
- j := i + int(aux)
- for c := 0; c < int(cnt); c++ {
- if j+16 > len(d) {
- break
- }
- // hash := f.ByteOrder.Uint32(d[j:j+4])
- // flags := f.ByteOrder.Uint16(d[j+4:j+6])
- other := f.ByteOrder.Uint16(d[j+6 : j+8])
- nameoff := f.ByteOrder.Uint32(d[j+8 : j+12])
- next := f.ByteOrder.Uint32(d[j+12 : j+16])
- name, _ = getString(str, int(nameoff))
- ndx := int(other)
- if ndx >= len(need) {
- a := make([]verneed, 2*(ndx+1))
- copy(a, need)
- need = a
- }
-
- need[ndx] = verneed{file, name}
- if next == 0 {
- break
- }
- j += int(next)
- }
-
- if next == 0 {
- break
- }
- i += int(next)
- }
-
- // Versym parallels symbol table, indexing into verneed.
- vs := f.SectionByType(SHT_GNU_VERSYM)
- if vs == nil {
- return
- }
- d, _ = vs.Data()
-
- f.gnuNeed = need
- f.gnuVersym = d
-}
-
-// gnuVersion adds Library and Version information to sym,
-// which came from offset i of the symbol table.
-func (f *File) gnuVersion(i int, sym *ImportedSymbol) {
- // Each entry is two bytes.
- i = i * 2
- if i >= len(f.gnuVersym) {
- return
- }
- j := int(f.ByteOrder.Uint16(f.gnuVersym[i:]))
- if j < 2 || j >= len(f.gnuNeed) {
- return
- }
- n := &f.gnuNeed[j]
- sym.Library = n.File
- sym.Version = n.Name
-}
-
-// ImportedLibraries returns the names of all libraries
-// referred to by the binary f that are expected to be
-// linked with the binary at dynamic link time.
-func (f *File) ImportedLibraries() ([]string, error) {
- return f.DynString(DT_NEEDED)
-}
-
-// DynString returns the strings listed for the given tag in the file's dynamic
-// section.
-//
-// The tag must be one that takes string values: DT_NEEDED, DT_SONAME, DT_RPATH, or
-// DT_RUNPATH.
-func (f *File) DynString(tag DynTag) ([]string, error) {
- switch tag {
- case DT_NEEDED, DT_SONAME, DT_RPATH, DT_RUNPATH:
- default:
- return nil, fmt.Errorf("non-string-valued tag %v", tag)
- }
- ds := f.SectionByType(SHT_DYNAMIC)
- if ds == nil {
- // not dynamic, so no libraries
- return nil, nil
- }
- d, err := ds.Data()
- if err != nil {
- return nil, err
- }
- str, err := f.stringTable(ds.Link)
- if err != nil {
- return nil, err
- }
- var all []string
- for len(d) > 0 {
- var t DynTag
- var v uint64
- switch f.Class {
- case ELFCLASS32:
- t = DynTag(f.ByteOrder.Uint32(d[0:4]))
- v = uint64(f.ByteOrder.Uint32(d[4:8]))
- d = d[8:]
- case ELFCLASS64:
- t = DynTag(f.ByteOrder.Uint64(d[0:8]))
- v = f.ByteOrder.Uint64(d[8:16])
- d = d[16:]
- }
- if t == tag {
- s, ok := getString(str, int(v))
- if ok {
- all = append(all, s)
- }
- }
- }
- return all, nil
-}
generated by cgit v1.2.3 (git 2.25.1) at 2024-04-25 05:13:31 +0000