summaryrefslogtreecommitdiffstats
path: root/vendor/github.com/google/gops/internal/objfile/elf.go
diff options
context:
space:
mode:
Diffstat (limited to 'vendor/github.com/google/gops/internal/objfile/elf.go')
-rw-r--r--vendor/github.com/google/gops/internal/objfile/elf.go124
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()
+}