mirror of
https://github.com/superseriousbusiness/gotosocial.git
synced 2024-12-05 10:02:47 +00:00
872 lines
23 KiB
Go
872 lines
23 KiB
Go
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// Copyright 2019 The Go Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file.
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// This package defines the Go object file format, and provide "low-level" functions
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// for reading and writing object files.
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// The object file is understood by the compiler, assembler, linker, and tools. They
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// have "high level" code that operates on object files, handling application-specific
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// logics, and use this package for the actual reading and writing. Specifically, the
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// code below:
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//
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// - cmd/internal/obj/objfile.go (used by cmd/asm and cmd/compile)
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// - cmd/internal/objfile/goobj.go (used cmd/nm, cmd/objdump)
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// - cmd/link/internal/loader package (used by cmd/link)
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//
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// If the object file format changes, they may (or may not) need to change.
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package goobj
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import (
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"bytes"
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"github.com/twitchyliquid64/golang-asm/bio"
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"crypto/sha1"
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"encoding/binary"
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"errors"
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"fmt"
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"github.com/twitchyliquid64/golang-asm/unsafeheader"
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"io"
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"unsafe"
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)
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// New object file format.
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//
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// Header struct {
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// Magic [...]byte // "\x00go116ld"
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// Fingerprint [8]byte
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// Flags uint32
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// Offsets [...]uint32 // byte offset of each block below
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// }
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//
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// Strings [...]struct {
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// Data [...]byte
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// }
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//
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// Autolib [...]struct { // imported packages (for file loading)
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// Pkg string
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// Fingerprint [8]byte
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// }
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//
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// PkgIndex [...]string // referenced packages by index
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//
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// Files [...]string
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//
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// SymbolDefs [...]struct {
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// Name string
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// ABI uint16
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// Type uint8
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// Flag uint8
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// Flag2 uint8
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// Size uint32
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// }
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// Hashed64Defs [...]struct { // short hashed (content-addressable) symbol definitions
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// ... // same as SymbolDefs
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// }
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// HashedDefs [...]struct { // hashed (content-addressable) symbol definitions
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// ... // same as SymbolDefs
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// }
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// NonPkgDefs [...]struct { // non-pkg symbol definitions
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// ... // same as SymbolDefs
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// }
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// NonPkgRefs [...]struct { // non-pkg symbol references
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// ... // same as SymbolDefs
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// }
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//
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// RefFlags [...]struct { // referenced symbol flags
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// Sym symRef
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// Flag uint8
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// Flag2 uint8
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// }
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//
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// Hash64 [...][8]byte
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// Hash [...][N]byte
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//
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// RelocIndex [...]uint32 // index to Relocs
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// AuxIndex [...]uint32 // index to Aux
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// DataIndex [...]uint32 // offset to Data
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//
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// Relocs [...]struct {
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// Off int32
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// Size uint8
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// Type uint8
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// Add int64
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// Sym symRef
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// }
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//
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// Aux [...]struct {
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// Type uint8
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// Sym symRef
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// }
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//
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// Data [...]byte
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// Pcdata [...]byte
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//
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// // blocks only used by tools (objdump, nm)
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//
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// RefNames [...]struct { // referenced symbol names
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// Sym symRef
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// Name string
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// // TODO: include ABI version as well?
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// }
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//
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// string is encoded as is a uint32 length followed by a uint32 offset
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// that points to the corresponding string bytes.
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//
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// symRef is struct { PkgIdx, SymIdx uint32 }.
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//
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// Slice type (e.g. []symRef) is encoded as a length prefix (uint32)
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// followed by that number of elements.
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//
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// The types below correspond to the encoded data structure in the
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// object file.
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// Symbol indexing.
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//
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// Each symbol is referenced with a pair of indices, { PkgIdx, SymIdx },
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// as the symRef struct above.
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//
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// PkgIdx is either a predeclared index (see PkgIdxNone below) or
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// an index of an imported package. For the latter case, PkgIdx is the
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// index of the package in the PkgIndex array. 0 is an invalid index.
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//
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// SymIdx is the index of the symbol in the given package.
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// - If PkgIdx is PkgIdxSelf, SymIdx is the index of the symbol in the
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// SymbolDefs array.
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// - If PkgIdx is PkgIdxHashed64, SymIdx is the index of the symbol in the
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// Hashed64Defs array.
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// - If PkgIdx is PkgIdxHashed, SymIdx is the index of the symbol in the
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// HashedDefs array.
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// - If PkgIdx is PkgIdxNone, SymIdx is the index of the symbol in the
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// NonPkgDefs array (could natually overflow to NonPkgRefs array).
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// - Otherwise, SymIdx is the index of the symbol in some other package's
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// SymbolDefs array.
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//
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// {0, 0} represents a nil symbol. Otherwise PkgIdx should not be 0.
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//
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// Hash contains the content hashes of content-addressable symbols, of
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// which PkgIdx is PkgIdxHashed, in the same order of HashedDefs array.
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// Hash64 is similar, for PkgIdxHashed64 symbols.
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//
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// RelocIndex, AuxIndex, and DataIndex contains indices/offsets to
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// Relocs/Aux/Data blocks, one element per symbol, first for all the
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// defined symbols, then all the defined hashed and non-package symbols,
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// in the same order of SymbolDefs/Hashed64Defs/HashedDefs/NonPkgDefs
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// arrays. For N total defined symbols, the array is of length N+1. The
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// last element is the total number of relocations (aux symbols, data
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// blocks, etc.).
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//
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// They can be accessed by index. For the i-th symbol, its relocations
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// are the RelocIndex[i]-th (inclusive) to RelocIndex[i+1]-th (exclusive)
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// elements in the Relocs array. Aux/Data are likewise. (The index is
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// 0-based.)
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// Auxiliary symbols.
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//
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// Each symbol may (or may not) be associated with a number of auxiliary
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// symbols. They are described in the Aux block. See Aux struct below.
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// Currently a symbol's Gotype, FuncInfo, and associated DWARF symbols
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// are auxiliary symbols.
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const stringRefSize = 8 // two uint32s
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type FingerprintType [8]byte
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func (fp FingerprintType) IsZero() bool { return fp == FingerprintType{} }
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// Package Index.
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const (
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PkgIdxNone = (1<<31 - 1) - iota // Non-package symbols
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PkgIdxHashed64 // Short hashed (content-addressable) symbols
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PkgIdxHashed // Hashed (content-addressable) symbols
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PkgIdxBuiltin // Predefined runtime symbols (ex: runtime.newobject)
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PkgIdxSelf // Symbols defined in the current package
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PkgIdxInvalid = 0
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// The index of other referenced packages starts from 1.
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)
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// Blocks
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const (
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BlkAutolib = iota
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BlkPkgIdx
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BlkFile
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BlkSymdef
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BlkHashed64def
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BlkHasheddef
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BlkNonpkgdef
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BlkNonpkgref
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BlkRefFlags
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BlkHash64
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BlkHash
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BlkRelocIdx
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BlkAuxIdx
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BlkDataIdx
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BlkReloc
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BlkAux
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BlkData
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BlkPcdata
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BlkRefName
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BlkEnd
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NBlk
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)
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// File header.
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// TODO: probably no need to export this.
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type Header struct {
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Magic string
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Fingerprint FingerprintType
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Flags uint32
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Offsets [NBlk]uint32
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}
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const Magic = "\x00go116ld"
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func (h *Header) Write(w *Writer) {
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w.RawString(h.Magic)
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w.Bytes(h.Fingerprint[:])
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w.Uint32(h.Flags)
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for _, x := range h.Offsets {
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w.Uint32(x)
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}
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}
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func (h *Header) Read(r *Reader) error {
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b := r.BytesAt(0, len(Magic))
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h.Magic = string(b)
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if h.Magic != Magic {
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return errors.New("wrong magic, not a Go object file")
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}
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off := uint32(len(h.Magic))
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copy(h.Fingerprint[:], r.BytesAt(off, len(h.Fingerprint)))
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off += 8
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h.Flags = r.uint32At(off)
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off += 4
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for i := range h.Offsets {
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h.Offsets[i] = r.uint32At(off)
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off += 4
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}
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return nil
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}
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func (h *Header) Size() int {
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return len(h.Magic) + 4 + 4*len(h.Offsets)
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}
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// Autolib
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type ImportedPkg struct {
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Pkg string
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Fingerprint FingerprintType
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}
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const importedPkgSize = stringRefSize + 8
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func (p *ImportedPkg) Write(w *Writer) {
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w.StringRef(p.Pkg)
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w.Bytes(p.Fingerprint[:])
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}
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// Symbol definition.
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//
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// Serialized format:
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// Sym struct {
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// Name string
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// ABI uint16
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// Type uint8
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// Flag uint8
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// Flag2 uint8
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// Siz uint32
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// Align uint32
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// }
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type Sym [SymSize]byte
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const SymSize = stringRefSize + 2 + 1 + 1 + 1 + 4 + 4
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const SymABIstatic = ^uint16(0)
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const (
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ObjFlagShared = 1 << iota // this object is built with -shared
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ObjFlagNeedNameExpansion // the linker needs to expand `"".` to package path in symbol names
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ObjFlagFromAssembly // object is from asm src, not go
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)
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// Sym.Flag
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const (
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SymFlagDupok = 1 << iota
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SymFlagLocal
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SymFlagTypelink
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SymFlagLeaf
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SymFlagNoSplit
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SymFlagReflectMethod
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SymFlagGoType
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SymFlagTopFrame
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)
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// Sym.Flag2
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const (
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SymFlagUsedInIface = 1 << iota
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SymFlagItab
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)
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// Returns the length of the name of the symbol.
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func (s *Sym) NameLen(r *Reader) int {
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return int(binary.LittleEndian.Uint32(s[:]))
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}
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func (s *Sym) Name(r *Reader) string {
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len := binary.LittleEndian.Uint32(s[:])
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off := binary.LittleEndian.Uint32(s[4:])
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return r.StringAt(off, len)
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}
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func (s *Sym) ABI() uint16 { return binary.LittleEndian.Uint16(s[8:]) }
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func (s *Sym) Type() uint8 { return s[10] }
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func (s *Sym) Flag() uint8 { return s[11] }
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func (s *Sym) Flag2() uint8 { return s[12] }
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func (s *Sym) Siz() uint32 { return binary.LittleEndian.Uint32(s[13:]) }
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func (s *Sym) Align() uint32 { return binary.LittleEndian.Uint32(s[17:]) }
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func (s *Sym) Dupok() bool { return s.Flag()&SymFlagDupok != 0 }
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func (s *Sym) Local() bool { return s.Flag()&SymFlagLocal != 0 }
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func (s *Sym) Typelink() bool { return s.Flag()&SymFlagTypelink != 0 }
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func (s *Sym) Leaf() bool { return s.Flag()&SymFlagLeaf != 0 }
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func (s *Sym) NoSplit() bool { return s.Flag()&SymFlagNoSplit != 0 }
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func (s *Sym) ReflectMethod() bool { return s.Flag()&SymFlagReflectMethod != 0 }
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func (s *Sym) IsGoType() bool { return s.Flag()&SymFlagGoType != 0 }
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func (s *Sym) TopFrame() bool { return s.Flag()&SymFlagTopFrame != 0 }
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func (s *Sym) UsedInIface() bool { return s.Flag2()&SymFlagUsedInIface != 0 }
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func (s *Sym) IsItab() bool { return s.Flag2()&SymFlagItab != 0 }
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func (s *Sym) SetName(x string, w *Writer) {
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binary.LittleEndian.PutUint32(s[:], uint32(len(x)))
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binary.LittleEndian.PutUint32(s[4:], w.stringOff(x))
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}
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func (s *Sym) SetABI(x uint16) { binary.LittleEndian.PutUint16(s[8:], x) }
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func (s *Sym) SetType(x uint8) { s[10] = x }
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func (s *Sym) SetFlag(x uint8) { s[11] = x }
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func (s *Sym) SetFlag2(x uint8) { s[12] = x }
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func (s *Sym) SetSiz(x uint32) { binary.LittleEndian.PutUint32(s[13:], x) }
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func (s *Sym) SetAlign(x uint32) { binary.LittleEndian.PutUint32(s[17:], x) }
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func (s *Sym) Write(w *Writer) { w.Bytes(s[:]) }
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// for testing
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func (s *Sym) fromBytes(b []byte) { copy(s[:], b) }
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// Symbol reference.
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type SymRef struct {
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PkgIdx uint32
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SymIdx uint32
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}
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// Hash64
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type Hash64Type [Hash64Size]byte
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const Hash64Size = 8
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// Hash
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type HashType [HashSize]byte
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const HashSize = sha1.Size
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// Relocation.
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//
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// Serialized format:
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// Reloc struct {
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// Off int32
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// Siz uint8
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// Type uint8
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// Add int64
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// Sym SymRef
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// }
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type Reloc [RelocSize]byte
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const RelocSize = 4 + 1 + 1 + 8 + 8
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func (r *Reloc) Off() int32 { return int32(binary.LittleEndian.Uint32(r[:])) }
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func (r *Reloc) Siz() uint8 { return r[4] }
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func (r *Reloc) Type() uint8 { return r[5] }
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func (r *Reloc) Add() int64 { return int64(binary.LittleEndian.Uint64(r[6:])) }
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func (r *Reloc) Sym() SymRef {
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return SymRef{binary.LittleEndian.Uint32(r[14:]), binary.LittleEndian.Uint32(r[18:])}
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}
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func (r *Reloc) SetOff(x int32) { binary.LittleEndian.PutUint32(r[:], uint32(x)) }
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func (r *Reloc) SetSiz(x uint8) { r[4] = x }
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func (r *Reloc) SetType(x uint8) { r[5] = x }
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func (r *Reloc) SetAdd(x int64) { binary.LittleEndian.PutUint64(r[6:], uint64(x)) }
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func (r *Reloc) SetSym(x SymRef) {
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binary.LittleEndian.PutUint32(r[14:], x.PkgIdx)
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binary.LittleEndian.PutUint32(r[18:], x.SymIdx)
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}
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func (r *Reloc) Set(off int32, size uint8, typ uint8, add int64, sym SymRef) {
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r.SetOff(off)
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r.SetSiz(size)
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r.SetType(typ)
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r.SetAdd(add)
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r.SetSym(sym)
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}
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func (r *Reloc) Write(w *Writer) { w.Bytes(r[:]) }
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// for testing
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func (r *Reloc) fromBytes(b []byte) { copy(r[:], b) }
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// Aux symbol info.
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||
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//
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||
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// Serialized format:
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||
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// Aux struct {
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||
|
// Type uint8
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||
|
// Sym SymRef
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||
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// }
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||
|
type Aux [AuxSize]byte
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||
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const AuxSize = 1 + 8
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|
||
|
// Aux Type
|
||
|
const (
|
||
|
AuxGotype = iota
|
||
|
AuxFuncInfo
|
||
|
AuxFuncdata
|
||
|
AuxDwarfInfo
|
||
|
AuxDwarfLoc
|
||
|
AuxDwarfRanges
|
||
|
AuxDwarfLines
|
||
|
|
||
|
// TODO: more. Pcdata?
|
||
|
)
|
||
|
|
||
|
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[:]) }
|
||
|
|
||
|
// 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 (*[1 << 20]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 (*[1 << 20]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))
|
||
|
}
|
||
|
|
||
|
// AuxDataBase returns the base offset of the aux data block.
|
||
|
func (r *Reader) PcdataBase() uint32 {
|
||
|
return r.h.Offsets[BlkPcdata]
|
||
|
}
|
||
|
|
||
|
// 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 }
|