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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-28 13:14:23 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-28 13:14:23 +0000
commit73df946d56c74384511a194dd01dbe099584fd1a (patch)
treefd0bcea490dd81327ddfbb31e215439672c9a068 /src/cmd/internal/goobj/objfile.go
parentInitial commit. (diff)
downloadgolang-1.16-73df946d56c74384511a194dd01dbe099584fd1a.tar.xz
golang-1.16-73df946d56c74384511a194dd01dbe099584fd1a.zip
Adding upstream version 1.16.10.upstream/1.16.10upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'src/cmd/internal/goobj/objfile.go')
-rw-r--r--src/cmd/internal/goobj/objfile.go874
1 files changed, 874 insertions, 0 deletions
diff --git a/src/cmd/internal/goobj/objfile.go b/src/cmd/internal/goobj/objfile.go
new file mode 100644
index 0000000..e6447e4
--- /dev/null
+++ b/src/cmd/internal/goobj/objfile.go
@@ -0,0 +1,874 @@
+// Copyright 2019 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.
+
+// This package defines the Go object file format, and provide "low-level" functions
+// for reading and writing object files.
+
+// The object file is understood by the compiler, assembler, linker, and tools. They
+// have "high level" code that operates on object files, handling application-specific
+// logics, and use this package for the actual reading and writing. Specifically, the
+// code below:
+//
+// - cmd/internal/obj/objfile.go (used by cmd/asm and cmd/compile)
+// - cmd/internal/objfile/goobj.go (used cmd/nm, cmd/objdump)
+// - cmd/link/internal/loader package (used by cmd/link)
+//
+// If the object file format changes, they may (or may not) need to change.
+
+package goobj
+
+import (
+ "bytes"
+ "cmd/internal/bio"
+ "crypto/sha1"
+ "encoding/binary"
+ "errors"
+ "fmt"
+ "internal/unsafeheader"
+ "io"
+ "unsafe"
+)
+
+// New object file format.
+//
+// Header struct {
+// Magic [...]byte // "\x00go116ld"
+// Fingerprint [8]byte
+// Flags uint32
+// Offsets [...]uint32 // byte offset of each block below
+// }
+//
+// Strings [...]struct {
+// Data [...]byte
+// }
+//
+// Autolib [...]struct { // imported packages (for file loading)
+// Pkg string
+// Fingerprint [8]byte
+// }
+//
+// PkgIndex [...]string // referenced packages by index
+//
+// Files [...]string
+//
+// SymbolDefs [...]struct {
+// Name string
+// ABI uint16
+// Type uint8
+// Flag uint8
+// Flag2 uint8
+// Size uint32
+// }
+// Hashed64Defs [...]struct { // short hashed (content-addressable) symbol definitions
+// ... // same as SymbolDefs
+// }
+// HashedDefs [...]struct { // hashed (content-addressable) symbol definitions
+// ... // same as SymbolDefs
+// }
+// NonPkgDefs [...]struct { // non-pkg symbol definitions
+// ... // same as SymbolDefs
+// }
+// NonPkgRefs [...]struct { // non-pkg symbol references
+// ... // same as SymbolDefs
+// }
+//
+// RefFlags [...]struct { // referenced symbol flags
+// Sym symRef
+// Flag uint8
+// Flag2 uint8
+// }
+//
+// Hash64 [...][8]byte
+// Hash [...][N]byte
+//
+// RelocIndex [...]uint32 // index to Relocs
+// AuxIndex [...]uint32 // index to Aux
+// DataIndex [...]uint32 // offset to Data
+//
+// Relocs [...]struct {
+// Off int32
+// Size uint8
+// Type uint8
+// Add int64
+// Sym symRef
+// }
+//
+// Aux [...]struct {
+// Type uint8
+// Sym symRef
+// }
+//
+// Data [...]byte
+// Pcdata [...]byte
+//
+// // blocks only used by tools (objdump, nm)
+//
+// RefNames [...]struct { // referenced symbol names
+// Sym symRef
+// Name string
+// // TODO: include ABI version as well?
+// }
+//
+// string is encoded as is a uint32 length followed by a uint32 offset
+// that points to the corresponding string bytes.
+//
+// symRef is struct { PkgIdx, SymIdx uint32 }.
+//
+// Slice type (e.g. []symRef) is encoded as a length prefix (uint32)
+// followed by that number of elements.
+//
+// The types below correspond to the encoded data structure in the
+// object file.
+
+// Symbol indexing.
+//
+// Each symbol is referenced with a pair of indices, { PkgIdx, SymIdx },
+// as the symRef struct above.
+//
+// PkgIdx is either a predeclared index (see PkgIdxNone below) or
+// an index of an imported package. For the latter case, PkgIdx is the
+// index of the package in the PkgIndex array. 0 is an invalid index.
+//
+// SymIdx is the index of the symbol in the given package.
+// - If PkgIdx is PkgIdxSelf, SymIdx is the index of the symbol in the
+// SymbolDefs array.
+// - If PkgIdx is PkgIdxHashed64, SymIdx is the index of the symbol in the
+// Hashed64Defs array.
+// - If PkgIdx is PkgIdxHashed, SymIdx is the index of the symbol in the
+// HashedDefs array.
+// - If PkgIdx is PkgIdxNone, SymIdx is the index of the symbol in the
+// NonPkgDefs array (could natually overflow to NonPkgRefs array).
+// - Otherwise, SymIdx is the index of the symbol in some other package's
+// SymbolDefs array.
+//
+// {0, 0} represents a nil symbol. Otherwise PkgIdx should not be 0.
+//
+// Hash contains the content hashes of content-addressable symbols, of
+// which PkgIdx is PkgIdxHashed, in the same order of HashedDefs array.
+// Hash64 is similar, for PkgIdxHashed64 symbols.
+//
+// RelocIndex, AuxIndex, and DataIndex contains indices/offsets to
+// Relocs/Aux/Data blocks, one element per symbol, first for all the
+// defined symbols, then all the defined hashed and non-package symbols,
+// in the same order of SymbolDefs/Hashed64Defs/HashedDefs/NonPkgDefs
+// arrays. For N total defined symbols, the array is of length N+1. The
+// last element is the total number of relocations (aux symbols, data
+// blocks, etc.).
+//
+// They can be accessed by index. For the i-th symbol, its relocations
+// are the RelocIndex[i]-th (inclusive) to RelocIndex[i+1]-th (exclusive)
+// elements in the Relocs array. Aux/Data are likewise. (The index is
+// 0-based.)
+
+// Auxiliary symbols.
+//
+// Each symbol may (or may not) be associated with a number of auxiliary
+// symbols. They are described in the Aux block. See Aux struct below.
+// Currently a symbol's Gotype, FuncInfo, and associated DWARF symbols
+// are auxiliary symbols.
+
+const stringRefSize = 8 // two uint32s
+
+type FingerprintType [8]byte
+
+func (fp FingerprintType) IsZero() bool { return fp == FingerprintType{} }
+
+// Package Index.
+const (
+ PkgIdxNone = (1<<31 - 1) - iota // Non-package symbols
+ PkgIdxHashed64 // Short hashed (content-addressable) symbols
+ PkgIdxHashed // Hashed (content-addressable) symbols
+ PkgIdxBuiltin // Predefined runtime symbols (ex: runtime.newobject)
+ PkgIdxSelf // Symbols defined in the current package
+ PkgIdxInvalid = 0
+ // The index of other referenced packages starts from 1.
+)
+
+// Blocks
+const (
+ BlkAutolib = iota
+ BlkPkgIdx
+ BlkFile
+ BlkSymdef
+ BlkHashed64def
+ BlkHasheddef
+ BlkNonpkgdef
+ BlkNonpkgref
+ BlkRefFlags
+ BlkHash64
+ BlkHash
+ BlkRelocIdx
+ BlkAuxIdx
+ BlkDataIdx
+ BlkReloc
+ BlkAux
+ BlkData
+ BlkPcdata
+ BlkRefName
+ BlkEnd
+ NBlk
+)
+
+// File header.
+// TODO: probably no need to export this.
+type Header struct {
+ Magic string
+ Fingerprint FingerprintType
+ Flags uint32
+ Offsets [NBlk]uint32
+}
+
+const Magic = "\x00go116ld"
+
+func (h *Header) Write(w *Writer) {
+ w.RawString(h.Magic)
+ w.Bytes(h.Fingerprint[:])
+ w.Uint32(h.Flags)
+ for _, x := range h.Offsets {
+ w.Uint32(x)
+ }
+}
+
+func (h *Header) Read(r *Reader) error {
+ b := r.BytesAt(0, len(Magic))
+ h.Magic = string(b)
+ if h.Magic != Magic {
+ return errors.New("wrong magic, not a Go object file")
+ }
+ off := uint32(len(h.Magic))
+ copy(h.Fingerprint[:], r.BytesAt(off, len(h.Fingerprint)))
+ off += 8
+ h.Flags = r.uint32At(off)
+ off += 4
+ for i := range h.Offsets {
+ h.Offsets[i] = r.uint32At(off)
+ off += 4
+ }
+ return nil
+}
+
+func (h *Header) Size() int {
+ return len(h.Magic) + 4 + 4*len(h.Offsets)
+}
+
+// Autolib
+type ImportedPkg struct {
+ Pkg string
+ Fingerprint FingerprintType
+}
+
+const importedPkgSize = stringRefSize + 8
+
+func (p *ImportedPkg) Write(w *Writer) {
+ w.StringRef(p.Pkg)
+ w.Bytes(p.Fingerprint[:])
+}
+
+// Symbol definition.
+//
+// Serialized format:
+// Sym struct {
+// Name string
+// ABI uint16
+// Type uint8
+// Flag uint8
+// Flag2 uint8
+// Siz uint32
+// Align uint32
+// }
+type Sym [SymSize]byte
+
+const SymSize = stringRefSize + 2 + 1 + 1 + 1 + 4 + 4
+
+const SymABIstatic = ^uint16(0)
+
+const (
+ ObjFlagShared = 1 << iota // this object is built with -shared
+ ObjFlagNeedNameExpansion // the linker needs to expand `"".` to package path in symbol names
+ ObjFlagFromAssembly // object is from asm src, not go
+)
+
+// Sym.Flag
+const (
+ SymFlagDupok = 1 << iota
+ SymFlagLocal
+ SymFlagTypelink
+ SymFlagLeaf
+ SymFlagNoSplit
+ SymFlagReflectMethod
+ SymFlagGoType
+ SymFlagTopFrame
+)
+
+// Sym.Flag2
+const (
+ SymFlagUsedInIface = 1 << iota
+ SymFlagItab
+)
+
+// Returns the length of the name of the symbol.
+func (s *Sym) NameLen(r *Reader) int {
+ return int(binary.LittleEndian.Uint32(s[:]))
+}
+
+func (s *Sym) Name(r *Reader) string {
+ len := binary.LittleEndian.Uint32(s[:])
+ off := binary.LittleEndian.Uint32(s[4:])
+ return r.StringAt(off, len)
+}
+
+func (s *Sym) ABI() uint16 { return binary.LittleEndian.Uint16(s[8:]) }
+func (s *Sym) Type() uint8 { return s[10] }
+func (s *Sym) Flag() uint8 { return s[11] }
+func (s *Sym) Flag2() uint8 { return s[12] }
+func (s *Sym) Siz() uint32 { return binary.LittleEndian.Uint32(s[13:]) }
+func (s *Sym) Align() uint32 { return binary.LittleEndian.Uint32(s[17:]) }
+
+func (s *Sym) Dupok() bool { return s.Flag()&SymFlagDupok != 0 }
+func (s *Sym) Local() bool { return s.Flag()&SymFlagLocal != 0 }
+func (s *Sym) Typelink() bool { return s.Flag()&SymFlagTypelink != 0 }
+func (s *Sym) Leaf() bool { return s.Flag()&SymFlagLeaf != 0 }
+func (s *Sym) NoSplit() bool { return s.Flag()&SymFlagNoSplit != 0 }
+func (s *Sym) ReflectMethod() bool { return s.Flag()&SymFlagReflectMethod != 0 }
+func (s *Sym) IsGoType() bool { return s.Flag()&SymFlagGoType != 0 }
+func (s *Sym) TopFrame() bool { return s.Flag()&SymFlagTopFrame != 0 }
+func (s *Sym) UsedInIface() bool { return s.Flag2()&SymFlagUsedInIface != 0 }
+func (s *Sym) IsItab() bool { return s.Flag2()&SymFlagItab != 0 }
+
+func (s *Sym) SetName(x string, w *Writer) {
+ binary.LittleEndian.PutUint32(s[:], uint32(len(x)))
+ binary.LittleEndian.PutUint32(s[4:], w.stringOff(x))
+}
+
+func (s *Sym) SetABI(x uint16) { binary.LittleEndian.PutUint16(s[8:], x) }
+func (s *Sym) SetType(x uint8) { s[10] = x }
+func (s *Sym) SetFlag(x uint8) { s[11] = x }
+func (s *Sym) SetFlag2(x uint8) { s[12] = x }
+func (s *Sym) SetSiz(x uint32) { binary.LittleEndian.PutUint32(s[13:], x) }
+func (s *Sym) SetAlign(x uint32) { binary.LittleEndian.PutUint32(s[17:], x) }
+
+func (s *Sym) Write(w *Writer) { w.Bytes(s[:]) }
+
+// for testing
+func (s *Sym) fromBytes(b []byte) { copy(s[:], b) }
+
+// Symbol reference.
+type SymRef struct {
+ PkgIdx uint32
+ SymIdx uint32
+}
+
+// Hash64
+type Hash64Type [Hash64Size]byte
+
+const Hash64Size = 8
+
+// Hash
+type HashType [HashSize]byte
+
+const HashSize = sha1.Size
+
+// Relocation.
+//
+// Serialized format:
+// Reloc struct {
+// Off int32
+// Siz uint8
+// Type uint8
+// Add int64
+// Sym SymRef
+// }
+type Reloc [RelocSize]byte
+
+const RelocSize = 4 + 1 + 1 + 8 + 8
+
+func (r *Reloc) Off() int32 { return int32(binary.LittleEndian.Uint32(r[:])) }
+func (r *Reloc) Siz() uint8 { return r[4] }
+func (r *Reloc) Type() uint8 { return r[5] }
+func (r *Reloc) Add() int64 { return int64(binary.LittleEndian.Uint64(r[6:])) }
+func (r *Reloc) Sym() SymRef {
+ return SymRef{binary.LittleEndian.Uint32(r[14:]), binary.LittleEndian.Uint32(r[18:])}
+}
+
+func (r *Reloc) SetOff(x int32) { binary.LittleEndian.PutUint32(r[:], uint32(x)) }
+func (r *Reloc) SetSiz(x uint8) { r[4] = x }
+func (r *Reloc) SetType(x uint8) { r[5] = x }
+func (r *Reloc) SetAdd(x int64) { binary.LittleEndian.PutUint64(r[6:], uint64(x)) }
+func (r *Reloc) SetSym(x SymRef) {
+ binary.LittleEndian.PutUint32(r[14:], x.PkgIdx)
+ binary.LittleEndian.PutUint32(r[18:], x.SymIdx)
+}
+
+func (r *Reloc) Set(off int32, size uint8, typ uint8, add int64, sym SymRef) {
+ r.SetOff(off)
+ r.SetSiz(size)
+ r.SetType(typ)
+ r.SetAdd(add)
+ r.SetSym(sym)
+}
+
+func (r *Reloc) Write(w *Writer) { w.Bytes(r[:]) }
+
+// for testing
+func (r *Reloc) fromBytes(b []byte) { copy(r[:], b) }
+
+// Aux symbol info.
+//
+// Serialized format:
+// Aux struct {
+// Type uint8
+// Sym SymRef
+// }
+type Aux [AuxSize]byte
+
+const AuxSize = 1 + 8
+
+// Aux Type
+const (
+ AuxGotype = iota
+ AuxFuncInfo
+ AuxFuncdata
+ AuxDwarfInfo
+ AuxDwarfLoc
+ AuxDwarfRanges
+ AuxDwarfLines
+ AuxPcsp
+ AuxPcfile
+ AuxPcline
+ AuxPcinline
+ AuxPcdata
+)
+
+func (a *Aux) Type() uint8 { return a[0] }
+func (a *Aux) Sym() SymRef {
+ return SymRef{binary.LittleEndian.Uint32(a[1:]), binary.LittleEndian.Uint32(a[5:])}
+}
+
+func (a *Aux) SetType(x uint8) { a[0] = x }
+func (a *Aux) SetSym(x SymRef) {
+ binary.LittleEndian.PutUint32(a[1:], x.PkgIdx)
+ binary.LittleEndian.PutUint32(a[5:], x.SymIdx)
+}
+
+func (a *Aux) Write(w *Writer) { w.Bytes(a[:]) }
+
+// for testing
+func (a *Aux) fromBytes(b []byte) { copy(a[:], b) }
+
+// Referenced symbol flags.
+//
+// Serialized format:
+// RefFlags struct {
+// Sym symRef
+// Flag uint8
+// Flag2 uint8
+// }
+type RefFlags [RefFlagsSize]byte
+
+const RefFlagsSize = 8 + 1 + 1
+
+func (r *RefFlags) Sym() SymRef {
+ return SymRef{binary.LittleEndian.Uint32(r[:]), binary.LittleEndian.Uint32(r[4:])}
+}
+func (r *RefFlags) Flag() uint8 { return r[8] }
+func (r *RefFlags) Flag2() uint8 { return r[9] }
+
+func (r *RefFlags) SetSym(x SymRef) {
+ binary.LittleEndian.PutUint32(r[:], x.PkgIdx)
+ binary.LittleEndian.PutUint32(r[4:], x.SymIdx)
+}
+func (r *RefFlags) SetFlag(x uint8) { r[8] = x }
+func (r *RefFlags) SetFlag2(x uint8) { r[9] = x }
+
+func (r *RefFlags) Write(w *Writer) { w.Bytes(r[:]) }
+
+// Used to construct an artifically large array type when reading an
+// item from the object file relocs section or aux sym section (needs
+// to work on 32-bit as well as 64-bit). See issue 41621.
+const huge = (1<<31 - 1) / RelocSize
+
+// Referenced symbol name.
+//
+// Serialized format:
+// RefName struct {
+// Sym symRef
+// Name string
+// }
+type RefName [RefNameSize]byte
+
+const RefNameSize = 8 + stringRefSize
+
+func (n *RefName) Sym() SymRef {
+ return SymRef{binary.LittleEndian.Uint32(n[:]), binary.LittleEndian.Uint32(n[4:])}
+}
+func (n *RefName) Name(r *Reader) string {
+ len := binary.LittleEndian.Uint32(n[8:])
+ off := binary.LittleEndian.Uint32(n[12:])
+ return r.StringAt(off, len)
+}
+
+func (n *RefName) SetSym(x SymRef) {
+ binary.LittleEndian.PutUint32(n[:], x.PkgIdx)
+ binary.LittleEndian.PutUint32(n[4:], x.SymIdx)
+}
+func (n *RefName) SetName(x string, w *Writer) {
+ binary.LittleEndian.PutUint32(n[8:], uint32(len(x)))
+ binary.LittleEndian.PutUint32(n[12:], w.stringOff(x))
+}
+
+func (n *RefName) Write(w *Writer) { w.Bytes(n[:]) }
+
+type Writer struct {
+ wr *bio.Writer
+ stringMap map[string]uint32
+ off uint32 // running offset
+}
+
+func NewWriter(wr *bio.Writer) *Writer {
+ return &Writer{wr: wr, stringMap: make(map[string]uint32)}
+}
+
+func (w *Writer) AddString(s string) {
+ if _, ok := w.stringMap[s]; ok {
+ return
+ }
+ w.stringMap[s] = w.off
+ w.RawString(s)
+}
+
+func (w *Writer) stringOff(s string) uint32 {
+ off, ok := w.stringMap[s]
+ if !ok {
+ panic(fmt.Sprintf("writeStringRef: string not added: %q", s))
+ }
+ return off
+}
+
+func (w *Writer) StringRef(s string) {
+ w.Uint32(uint32(len(s)))
+ w.Uint32(w.stringOff(s))
+}
+
+func (w *Writer) RawString(s string) {
+ w.wr.WriteString(s)
+ w.off += uint32(len(s))
+}
+
+func (w *Writer) Bytes(s []byte) {
+ w.wr.Write(s)
+ w.off += uint32(len(s))
+}
+
+func (w *Writer) Uint64(x uint64) {
+ var b [8]byte
+ binary.LittleEndian.PutUint64(b[:], x)
+ w.wr.Write(b[:])
+ w.off += 8
+}
+
+func (w *Writer) Uint32(x uint32) {
+ var b [4]byte
+ binary.LittleEndian.PutUint32(b[:], x)
+ w.wr.Write(b[:])
+ w.off += 4
+}
+
+func (w *Writer) Uint16(x uint16) {
+ var b [2]byte
+ binary.LittleEndian.PutUint16(b[:], x)
+ w.wr.Write(b[:])
+ w.off += 2
+}
+
+func (w *Writer) Uint8(x uint8) {
+ w.wr.WriteByte(x)
+ w.off++
+}
+
+func (w *Writer) Offset() uint32 {
+ return w.off
+}
+
+type Reader struct {
+ b []byte // mmapped bytes, if not nil
+ readonly bool // whether b is backed with read-only memory
+
+ rd io.ReaderAt
+ start uint32
+ h Header // keep block offsets
+}
+
+func NewReaderFromBytes(b []byte, readonly bool) *Reader {
+ r := &Reader{b: b, readonly: readonly, rd: bytes.NewReader(b), start: 0}
+ err := r.h.Read(r)
+ if err != nil {
+ return nil
+ }
+ return r
+}
+
+func (r *Reader) BytesAt(off uint32, len int) []byte {
+ if len == 0 {
+ return nil
+ }
+ end := int(off) + len
+ return r.b[int(off):end:end]
+}
+
+func (r *Reader) uint64At(off uint32) uint64 {
+ b := r.BytesAt(off, 8)
+ return binary.LittleEndian.Uint64(b)
+}
+
+func (r *Reader) int64At(off uint32) int64 {
+ return int64(r.uint64At(off))
+}
+
+func (r *Reader) uint32At(off uint32) uint32 {
+ b := r.BytesAt(off, 4)
+ return binary.LittleEndian.Uint32(b)
+}
+
+func (r *Reader) int32At(off uint32) int32 {
+ return int32(r.uint32At(off))
+}
+
+func (r *Reader) uint16At(off uint32) uint16 {
+ b := r.BytesAt(off, 2)
+ return binary.LittleEndian.Uint16(b)
+}
+
+func (r *Reader) uint8At(off uint32) uint8 {
+ b := r.BytesAt(off, 1)
+ return b[0]
+}
+
+func (r *Reader) StringAt(off uint32, len uint32) string {
+ b := r.b[off : off+len]
+ if r.readonly {
+ return toString(b) // backed by RO memory, ok to make unsafe string
+ }
+ return string(b)
+}
+
+func toString(b []byte) string {
+ if len(b) == 0 {
+ return ""
+ }
+
+ var s string
+ hdr := (*unsafeheader.String)(unsafe.Pointer(&s))
+ hdr.Data = unsafe.Pointer(&b[0])
+ hdr.Len = len(b)
+
+ return s
+}
+
+func (r *Reader) StringRef(off uint32) string {
+ l := r.uint32At(off)
+ return r.StringAt(r.uint32At(off+4), l)
+}
+
+func (r *Reader) Fingerprint() FingerprintType {
+ return r.h.Fingerprint
+}
+
+func (r *Reader) Autolib() []ImportedPkg {
+ n := (r.h.Offsets[BlkAutolib+1] - r.h.Offsets[BlkAutolib]) / importedPkgSize
+ s := make([]ImportedPkg, n)
+ off := r.h.Offsets[BlkAutolib]
+ for i := range s {
+ s[i].Pkg = r.StringRef(off)
+ copy(s[i].Fingerprint[:], r.BytesAt(off+stringRefSize, len(s[i].Fingerprint)))
+ off += importedPkgSize
+ }
+ return s
+}
+
+func (r *Reader) Pkglist() []string {
+ n := (r.h.Offsets[BlkPkgIdx+1] - r.h.Offsets[BlkPkgIdx]) / stringRefSize
+ s := make([]string, n)
+ off := r.h.Offsets[BlkPkgIdx]
+ for i := range s {
+ s[i] = r.StringRef(off)
+ off += stringRefSize
+ }
+ return s
+}
+
+func (r *Reader) NPkg() int {
+ return int(r.h.Offsets[BlkPkgIdx+1]-r.h.Offsets[BlkPkgIdx]) / stringRefSize
+}
+
+func (r *Reader) Pkg(i int) string {
+ off := r.h.Offsets[BlkPkgIdx] + uint32(i)*stringRefSize
+ return r.StringRef(off)
+}
+
+func (r *Reader) NFile() int {
+ return int(r.h.Offsets[BlkFile+1]-r.h.Offsets[BlkFile]) / stringRefSize
+}
+
+func (r *Reader) File(i int) string {
+ off := r.h.Offsets[BlkFile] + uint32(i)*stringRefSize
+ return r.StringRef(off)
+}
+
+func (r *Reader) NSym() int {
+ return int(r.h.Offsets[BlkSymdef+1]-r.h.Offsets[BlkSymdef]) / SymSize
+}
+
+func (r *Reader) NHashed64def() int {
+ return int(r.h.Offsets[BlkHashed64def+1]-r.h.Offsets[BlkHashed64def]) / SymSize
+}
+
+func (r *Reader) NHasheddef() int {
+ return int(r.h.Offsets[BlkHasheddef+1]-r.h.Offsets[BlkHasheddef]) / SymSize
+}
+
+func (r *Reader) NNonpkgdef() int {
+ return int(r.h.Offsets[BlkNonpkgdef+1]-r.h.Offsets[BlkNonpkgdef]) / SymSize
+}
+
+func (r *Reader) NNonpkgref() int {
+ return int(r.h.Offsets[BlkNonpkgref+1]-r.h.Offsets[BlkNonpkgref]) / SymSize
+}
+
+// SymOff returns the offset of the i-th symbol.
+func (r *Reader) SymOff(i uint32) uint32 {
+ return r.h.Offsets[BlkSymdef] + uint32(i*SymSize)
+}
+
+// Sym returns a pointer to the i-th symbol.
+func (r *Reader) Sym(i uint32) *Sym {
+ off := r.SymOff(i)
+ return (*Sym)(unsafe.Pointer(&r.b[off]))
+}
+
+// NRefFlags returns the number of referenced symbol flags.
+func (r *Reader) NRefFlags() int {
+ return int(r.h.Offsets[BlkRefFlags+1]-r.h.Offsets[BlkRefFlags]) / RefFlagsSize
+}
+
+// RefFlags returns a pointer to the i-th referenced symbol flags.
+// Note: here i is not a local symbol index, just a counter.
+func (r *Reader) RefFlags(i int) *RefFlags {
+ off := r.h.Offsets[BlkRefFlags] + uint32(i*RefFlagsSize)
+ return (*RefFlags)(unsafe.Pointer(&r.b[off]))
+}
+
+// Hash64 returns the i-th short hashed symbol's hash.
+// Note: here i is the index of short hashed symbols, not all symbols
+// (unlike other accessors).
+func (r *Reader) Hash64(i uint32) uint64 {
+ off := r.h.Offsets[BlkHash64] + uint32(i*Hash64Size)
+ return r.uint64At(off)
+}
+
+// Hash returns a pointer to the i-th hashed symbol's hash.
+// Note: here i is the index of hashed symbols, not all symbols
+// (unlike other accessors).
+func (r *Reader) Hash(i uint32) *HashType {
+ off := r.h.Offsets[BlkHash] + uint32(i*HashSize)
+ return (*HashType)(unsafe.Pointer(&r.b[off]))
+}
+
+// NReloc returns the number of relocations of the i-th symbol.
+func (r *Reader) NReloc(i uint32) int {
+ relocIdxOff := r.h.Offsets[BlkRelocIdx] + uint32(i*4)
+ return int(r.uint32At(relocIdxOff+4) - r.uint32At(relocIdxOff))
+}
+
+// RelocOff returns the offset of the j-th relocation of the i-th symbol.
+func (r *Reader) RelocOff(i uint32, j int) uint32 {
+ relocIdxOff := r.h.Offsets[BlkRelocIdx] + uint32(i*4)
+ relocIdx := r.uint32At(relocIdxOff)
+ return r.h.Offsets[BlkReloc] + (relocIdx+uint32(j))*uint32(RelocSize)
+}
+
+// Reloc returns a pointer to the j-th relocation of the i-th symbol.
+func (r *Reader) Reloc(i uint32, j int) *Reloc {
+ off := r.RelocOff(i, j)
+ return (*Reloc)(unsafe.Pointer(&r.b[off]))
+}
+
+// Relocs returns a pointer to the relocations of the i-th symbol.
+func (r *Reader) Relocs(i uint32) []Reloc {
+ off := r.RelocOff(i, 0)
+ n := r.NReloc(i)
+ return (*[huge]Reloc)(unsafe.Pointer(&r.b[off]))[:n:n]
+}
+
+// NAux returns the number of aux symbols of the i-th symbol.
+func (r *Reader) NAux(i uint32) int {
+ auxIdxOff := r.h.Offsets[BlkAuxIdx] + i*4
+ return int(r.uint32At(auxIdxOff+4) - r.uint32At(auxIdxOff))
+}
+
+// AuxOff returns the offset of the j-th aux symbol of the i-th symbol.
+func (r *Reader) AuxOff(i uint32, j int) uint32 {
+ auxIdxOff := r.h.Offsets[BlkAuxIdx] + i*4
+ auxIdx := r.uint32At(auxIdxOff)
+ return r.h.Offsets[BlkAux] + (auxIdx+uint32(j))*uint32(AuxSize)
+}
+
+// Aux returns a pointer to the j-th aux symbol of the i-th symbol.
+func (r *Reader) Aux(i uint32, j int) *Aux {
+ off := r.AuxOff(i, j)
+ return (*Aux)(unsafe.Pointer(&r.b[off]))
+}
+
+// Auxs returns the aux symbols of the i-th symbol.
+func (r *Reader) Auxs(i uint32) []Aux {
+ off := r.AuxOff(i, 0)
+ n := r.NAux(i)
+ return (*[huge]Aux)(unsafe.Pointer(&r.b[off]))[:n:n]
+}
+
+// DataOff returns the offset of the i-th symbol's data.
+func (r *Reader) DataOff(i uint32) uint32 {
+ dataIdxOff := r.h.Offsets[BlkDataIdx] + i*4
+ return r.h.Offsets[BlkData] + r.uint32At(dataIdxOff)
+}
+
+// DataSize returns the size of the i-th symbol's data.
+func (r *Reader) DataSize(i uint32) int {
+ dataIdxOff := r.h.Offsets[BlkDataIdx] + i*4
+ return int(r.uint32At(dataIdxOff+4) - r.uint32At(dataIdxOff))
+}
+
+// Data returns the i-th symbol's data.
+func (r *Reader) Data(i uint32) []byte {
+ dataIdxOff := r.h.Offsets[BlkDataIdx] + i*4
+ base := r.h.Offsets[BlkData]
+ off := r.uint32At(dataIdxOff)
+ end := r.uint32At(dataIdxOff + 4)
+ return r.BytesAt(base+off, int(end-off))
+}
+
+// NRefName returns the number of referenced symbol names.
+func (r *Reader) NRefName() int {
+ return int(r.h.Offsets[BlkRefName+1]-r.h.Offsets[BlkRefName]) / RefNameSize
+}
+
+// RefName returns a pointer to the i-th referenced symbol name.
+// Note: here i is not a local symbol index, just a counter.
+func (r *Reader) RefName(i int) *RefName {
+ off := r.h.Offsets[BlkRefName] + uint32(i*RefNameSize)
+ return (*RefName)(unsafe.Pointer(&r.b[off]))
+}
+
+// ReadOnly returns whether r.BytesAt returns read-only bytes.
+func (r *Reader) ReadOnly() bool {
+ return r.readonly
+}
+
+// Flags returns the flag bits read from the object file header.
+func (r *Reader) Flags() uint32 {
+ return r.h.Flags
+}
+
+func (r *Reader) Shared() bool { return r.Flags()&ObjFlagShared != 0 }
+func (r *Reader) NeedNameExpansion() bool { return r.Flags()&ObjFlagNeedNameExpansion != 0 }
+func (r *Reader) FromAssembly() bool { return r.Flags()&ObjFlagFromAssembly != 0 }