diff options
Diffstat (limited to 'vendor/github.com/google/gops/internal/objfile/elf.go')
-rw-r--r-- | vendor/github.com/google/gops/internal/objfile/elf.go | 124 |
1 files changed, 124 insertions, 0 deletions
diff --git a/vendor/github.com/google/gops/internal/objfile/elf.go b/vendor/github.com/google/gops/internal/objfile/elf.go new file mode 100644 index 00000000..4ab7e6de --- /dev/null +++ b/vendor/github.com/google/gops/internal/objfile/elf.go @@ -0,0 +1,124 @@ +// Copyright 2013 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. + +// Parsing of ELF executables (Linux, FreeBSD, and so on). + +package objfile + +import ( + "debug/dwarf" + "debug/elf" + "encoding/binary" + "fmt" + "os" +) + +type elfFile struct { + elf *elf.File +} + +func openElf(r *os.File) (rawFile, error) { + f, err := elf.NewFile(r) + if err != nil { + return nil, err + } + return &elfFile{f}, nil +} + +func (f *elfFile) symbols() ([]Sym, error) { + elfSyms, err := f.elf.Symbols() + if err != nil { + return nil, err + } + + var syms []Sym + for _, s := range elfSyms { + sym := Sym{Addr: s.Value, Name: s.Name, Size: int64(s.Size), Code: '?'} + switch s.Section { + case elf.SHN_UNDEF: + sym.Code = 'U' + case elf.SHN_COMMON: + sym.Code = 'B' + default: + i := int(s.Section) + if i < 0 || i >= len(f.elf.Sections) { + break + } + sect := f.elf.Sections[i] + switch sect.Flags & (elf.SHF_WRITE | elf.SHF_ALLOC | elf.SHF_EXECINSTR) { + case elf.SHF_ALLOC | elf.SHF_EXECINSTR: + sym.Code = 'T' + case elf.SHF_ALLOC: + sym.Code = 'R' + case elf.SHF_ALLOC | elf.SHF_WRITE: + sym.Code = 'D' + } + } + if elf.ST_BIND(s.Info) == elf.STB_LOCAL { + sym.Code += 'a' - 'A' + } + syms = append(syms, sym) + } + + return syms, nil +} + +func (f *elfFile) pcln() (textStart uint64, symtab, pclntab []byte, err error) { + if sect := f.elf.Section(".text"); sect != nil { + textStart = sect.Addr + } + if sect := f.elf.Section(".gosymtab"); sect != nil { + if symtab, err = sect.Data(); err != nil { + return 0, nil, nil, err + } + } + if sect := f.elf.Section(".gopclntab"); sect != nil { + if pclntab, err = sect.Data(); err != nil { + return 0, nil, nil, err + } + } + return textStart, symtab, pclntab, nil +} + +func (f *elfFile) text() (textStart uint64, text []byte, err error) { + sect := f.elf.Section(".text") + if sect == nil { + return 0, nil, fmt.Errorf("text section not found") + } + textStart = sect.Addr + text, err = sect.Data() + return +} + +func (f *elfFile) goarch() string { + switch f.elf.Machine { + case elf.EM_386: + return "386" + case elf.EM_X86_64: + return "amd64" + case elf.EM_ARM: + return "arm" + case elf.EM_PPC64: + if f.elf.ByteOrder == binary.LittleEndian { + return "ppc64le" + } + return "ppc64" + case elf.EM_S390: + return "s390x" + } + return "" +} + +func (f *elfFile) loadAddress() (uint64, error) { + for _, p := range f.elf.Progs { + if p.Type == elf.PT_LOAD { + return p.Vaddr, nil + } + } + return 0, fmt.Errorf("unknown load address") +} + +func (f *elfFile) dwarf() (*dwarf.Data, error) { + return f.elf.DWARF() +} |